text:
Serviços Personalizados
Links relacionados
- Citado por Google
- Similares em Google
Journal of the South African Institution of Civil Engineering
versão On-line ISSN 2309-8775
versão impressa ISSN 1021-2019
J. S. Afr. Inst. Civ. Eng. vol.54 no.2 Midrand Jan. 2012
A step towards standardising accelerated corrosion tests on laboratory reinforced concrete specimens
G Malumbela; P Moyo; M Alexander
Natural steel corrosion of reinforced concrete (RC) structures is a slow process which researchers find necessary to accelerate in laboratory tests to obtain needed damage in a short time. Regrettably, there is no standard procedure for accelerating steel corrosion in RC specimens. Researchers therefore continue to use various techniques to accelerate it. Unfortunately, structural damage and rate of steel corrosion are dependent on the accelerated corrosion technique used. Despite that, results obtained by researchers are applied by structural engineers and asset managers to in-service structures. This paper reviews previous techniques used to accelerate steel corrosion. Where possible it proposes standard procedures to accelerate steel corrosion. In other instances it points out needed further research. One of the procedures recommended in the paper is to contaminate selected faces of RC specimens with chlorides, as opposed to immersing samples in NaCl solution or adding chlorides to concrete mixes. It is also recommended to allow specimens to sufficiently dry during steel corrosion so as to promote steel corrosion.
Keywords: accelerated corrosion, reinforced concrete, deterioration
Steel corrosion causes the most damage in in-service RC structures near the marine environment. However, in laboratory terms, the process of natural steel corrosion is very slow, needing tens of years to cause reasonable structural damage. For example, François & Arliguie (1998), Castel et al (2003), Vidal et al (2007) and Zhang et al (2009a,b; 2010), who allowed their laboratory specimens to corrode naturally, had to wait for four years for steel corrosion to start and an additional two years for first cracking to occur. They only obtained reasonable structural damage after 20 years. These times are not often afforded in laboratory tests. Researchers, understandably, have and continue to use various techniques to accelerate steel corrosion so as to shorten the needed testing time. In doing so they anticipate that structural damage under accelerated tests is proportional to damage caused by natural steel corrosion.
It should be pointed out that results obtained by researchers on laboratory specimens that are subjected to accelerated corrosion tests are often passed on to structural engineers and asset managers to apply them to real RC structures which corrode in the field. If they are not applicable to those structures then there is likelihood for engineers to authorise repairs of corroding RC structures at dangerous levels of steel corrosion or when load-bearing capacities of structures are still adequate. For the safety of occupants of corroding RC structures, as well as to minimise costs from unnecessary repairs, there is need to understand well how to apply (if at all applicable) results from accelerated laboratory tests to in-service structures.
This paper discusses various techniques that are often used in research laboratories to accelerate steel corrosion. It then compares conditions and results between the procedures, and where possible, associates them with those from in-service conditions. Finally, it proposes and points out needed research to establish a standard procedure that should be used in laboratories to study behaviour of corroding RC structures. The focus of the paper is on steel corrosion caused by chloride attack. It is also aimed at steel corrosion carried out with the intention to understand structural behaviour of corroding RC members. Issues regarding effects of accelerated corrosion on the electrochemical nature of RC elements were discussed in detail by Poursaee & Hansson (2009). In their discussion, they strongly discouraged accelerating steel corrosion for the reason that it harms the electrochemical nature of concrete. If concern is limited to the electrochemistry of concrete then adequate results can be obtained within a reasonable time frame, even when corrosion is natural. For example, a period of four years which François & Arliguie (1998), Castel et al (2003), Vidal et al (2007) and Zhang et al (2009a,b; 2010) had to wait for their specimens to start corroding is achievable in laboratory tests. However, and as previously mentioned, if interest is on structural behaviour then much longer testing periods are required. Accelerated corrosion is therefore often used to reduce this time of testing. The following section discusses various procedures used to accelerate steel corrosion and how they affect structural behaviour.
Concrete normally has an alkaline environment that protects embedded steel from corrosion. This environment can be destroyed by carbonation or by chloride attack. As already mentioned, it may take some years for sufficient chlorides to ingress cover concrete and de-passify steel. To hurriedly depassify it, some researchers opted to mix concrete with chlorides ranging from 1% (Mangat & Elgarf 1999) to 5% (El Maaddawy & Soudki 2003) by weight of cement. Others immersed their cured samples in tanks with NaCl solution with concentration from 3% (Cairns et al 2008) to 5% (Cabrera 1996) by weight of the solution. Levels of concentration of chlorides were often selected to simulate chloride concentration of seawater which has a salt concentration of about 3.5%. Note that both procedures above were used by some researchers (Azad et al 2007; Mangat & Elgarf 1999; Cairns et al 2008). According to Poursaee & Hansson (2009), if chlorides are added to a concrete mix, de-passivation of steel is immediate. Therefore the time required for steel to depassivate, which is often used in service life models, does not exist (Tuutti 1980). Understandably, Poursaee & Hansson (2009) strongly discouraged this procedure. They rather recommended that steel firstly be allowed to passivate before introducing chlorides to break the passive film.
One important element not discussed by Poursaee & Hansson (2009), but which emphasises their recommendation, is that adding chlorides to concrete results in uniform distribution of corrosion agents around the steel. Under natural steel corrosion, however, limited faces of a structure are often exposed to chloride attack. In addition, chlorides and other deleterious compounds are purposely excluded from concrete mixes in practice.
In an attempt to better represent natural steel corrosion, some researchers contaminated selected faces of their cured specimens with chlorides. This was achieved by either building NaCl ponds on surfaces of specimens to be contaminated (Yoon et al 2000; Malumbela et al 2009) or by selectively spraying them with salt solution (Zhang et al 2009a,b; Zhang et al 2010; Rio et al 2005). Under this selective contamination of RC specimens with chlorides, Malumbela et al (2011), Yuan & Ji (2009) and Yuan et al (2007) found steel corrosion to be localised within the direction of ingress of corrosion agents. Its implication was that compared to non-contaminated faces, larger tensile strains (especially prior to cover cracking) were measured on contaminated faces of concrete as shown in Figure 1 (Malumbela et al 2011).
In modelling time to cover cracking, Yuan & Ji (2009) proposed that the remaining bar diameter should be taken as elliptical shaped rather than circular, as used by many other researchers (Liu & Weyers 1998; El Maaddawy & Soudki 2007; Bhargava et al 2006). Jang & Oh (2010) and Malumbela et al (2011) demonstrated that assuming uniform loss of steel underestimates pressure applied by expansive corrosion products and hence overestimates resistance of the cover concrete to cracking that is observed under partial surface steel corrosion. Following discussions by Poursaee & Hansson (2009), Yuan & Ji (2009), Yuan et al (2007), Jang & Oh (2010) and Malumbela et al (2011), it is recommended that in accelerated corrosion tests:
i. Steel should be allowed to passivate before adding chlorides to concrete. This is equivalent to saying chlorides should be added externally and not be mixed with concrete.
ii. Only selected faces of concrete elements should be contaminated with chlorides. Specimens should not be submerged in salt solutions. This point will be further discussed later.
Corrosion of steel embedded in concrete occurs by an oxidation-reduction reaction. Loss in steel occurs at the anode where electrons are also produced and transferred to the cathode. This flow of electrons produces a small current which is often divided by the surface area of an anode to give current density. According to Andrade & Alonso (2001) and Alonso et al (1998), current density due to natural steel corrosion is often between 0.1 and 10 μA/cm2 but occasionally reaches 100 μA/cm2. Researchers make use of this current to speed up laboratory corrosion tests. They apply a larger direct current and adjust it such that reinforcing steel bars which they need to corrode are connected to a positive terminal, and an artificial steel bar/plate is connected to a negative terminal. Reinforcing steel bars therefore become the anode and the artificial steel bar/plate becomes the cathode. A salt electrolyte (aqueous NaCl or CaCl2) is used to provide electrical contact between the anode and the cathode. This procedure increases electrons that flow around the circuit. Bear in mind that from basic chemistry each reaction (oxidation/reduction) should always be balanced. It is clear that to balance increased electrons from the impressed current, more cations and anions are respectively produced at the anode and at the cathode. At the anode, this is achieved by an increased rate of loss of steel.
The level of impressed current density has varied greatly [from 3 A/cm2 (Alonso et al 1998) to 10400 A/cm2 (Almusallam et al 1996)] between researchers. Assuming proportional structural damage due to accelerated tests, a level of damage caused by a current density of 3 A/cm2 over a period of one year can be obtained within two hours when a current density of 10400 μA/cm2 is used. Should accelerated tests give proportional damage then there is little value in using low rates of steel corrosion.
To assess the effect of varying current densities on the proportion of structural damage, Mangat & Elgarf (1999) measured slopes of load-deflection curves of RC specimens that were corroded with corrosion rates from 1000 to 4000 μA/cm2. The concrete mix that they used for RC specimens had 1% NaCl salt by cement weight, and during the accelerated test their specimens were immersed in a 3.5% NaCl solution. At lower levels of steel corrosion (<10% mass loss), Mangat & Elgarf (1999) found little influence of corrosion rates on the stiffness of corroded specimens. However, at mass losses of steel above 10%, slopes of load-deflection curves or stiffness of corroded RC specimens were severely influenced by the rate of steel corrosion. For example, at a mass loss of steel of 15%, a specimen that was corroded with a current density of 4000 μA/cm2 needed a load of 26 kN to cause a deflection of 3 mm (stiffness = 8.7 kN/mm). At the same level of steel corrosion, a similar specimen that was corroded with a current density of 1000 μA/cm2 exhibited a deflection of 3 mm at a load of 38 kN (stiffness = 12.7 kN/mm). This indicates that at the same level of steel corrosion, there was a larger loss in stiffness of specimens that were corroded under a higher current density. Therefore, if loss in stiffness were to be used to predict levels of steel corrosion, its relation with corrosion levels from accelerated tests would result in engineers underestimating levels of steel corrosion in in-service structures.
Mangat & Elgarf (1999) asserted that for accelerated corrosion tests in laboratory specimens, especially when the target level of steel corrosion is high, the lowest practical corrosion rate should be used to accelerate reinforcement corrosion. Since they used corrosion rates that ranged from 1000 to 4000 A/cm2, it is reasonable to assume from their results that a corrosion rate that is below 1000 A/cm2 is appropriate for laboratory tests. One of the drawbacks with this work is that it used parameters that were only measured at the end of the corrosion process. It therefore does not provide the influence of the rate of steel corrosion on the much-needed rate of change of parameters with an increase in the level of steel corrosion. In addition, the corrosion process used does not give partial surface steel corrosion which Yuan & Ji (2009), Yuan et al (2007) and Jang & Oh (2010) contended to be more representative of in-service conditions.
El Maaddawy & Soudki (2003) conducted another research to find an impressed current density that can produce desired structural damage in a short time without excessively altering structural response under natural steel corrosion. In their work the researchers used rate of widening of corrosion cracks and average mass loss of steel at the end of corrosion tests as parameters that indicate corrosion damage. Crack widths were measured at one point on side faces of specimens using a demountable mechanical (demec) gauge with a gauge length of 50 mm. Depassivation of steel was accelerated by mixing concrete with 5% NaCl by weight of cement. Current densities assessed ranged from 100 to 500 μA/cm2.
They found that at corrosion crack widths below 0.03 mm (which corresponded to a theoretical mass loss of steel from Faraday's Law of 0.8%), specimens corroded using various current densities which exhibited a similar rate of expansion of the cover concrete. At larger crack widths (>0.03 mm), they found specimens subjected to current densities above 350 A/cm2 to exhibit a significantly larger rate of widening of corrosion cracks (up to four times) than specimens that were subjected to current densities below 200 μA/cm2. Interestingly though, they found that regardless of the level of impressed current density used, average mass losses of steel at the end of corrosion tests were within 4% of theoretical mass losses of steel predicted from Faraday's Law. These results indicate that if corrosion crack widths were to be used to predict levels of steel corrosion, relations between crack widths and mass loss of steel from highly accelerated tests would underestimate steel corrosion in in-service structures. Assuming a linear increase in mass loss of steel and crack widths, under highly accelerated tests (500 A/cm2), they found a crack width of 1 mm to correspond to mass loss of steel of 7.3%. However, at lower corrosion rates (100 A/cm2 and 200 μA/cm2) a crack width of 1 mm was found to correspond to a mass loss of steel of 13.3%. El Maaddawy & Soudki (2003) concluded that an impressed current density below 200 A/cm2 does not excessively alter the structural performance of corrosion-affected RC specimens that would be observed under natural steel corrosion.
It should be mentioned that El Maaddawy & Soudki (2003) initially observed two corrosion cracks near each corroding bar and each crack propagated parallel to the bar. These cracks were either on the top face or on the side face. Interestingly, when the level of steel corrosion was increased, a third crack appeared next to a corroding bar, but on a face that was uncracked. This indicates that the pattern of corrosion cracks changed with an increase in the level of steel corrosion. Similar change in crack patterns as steel corrosion increased was reported by Malumbela et al (2010a). They found that when a second crack appeared, the first crack ceased to widen. Certainly, specimens that exhibit this crack pattern will have narrower cracks than those that only exhibit a single crack. This was also found by Zhang et al (2010). This argument certainly questions the use of crack widths without full understanding of crack patterns to specify the level of current density to be used in accelerated corrosion tests. Bear in mind that current density used by Malumbela et al (2010a) was 189 A/cm2 which is within the limit proposed by El Maaddawy & Soudki (2003).
Contrary to findings by El Maaddawy & Soudki (2003), Alonso et al (1998) found that, for a chosen crack width, higher penetration depth (more than three times larger) of steel was needed when applying a current density of 100 A/cm2 than when applying a density of 3 A/cm2. This implies that crack widths increase faster with a lower corrosion rate (3 A/cm2) than with a higher corrosion rate (100 A/cm2). Somewhat similar to findings by Alonso et al (1998), Malumbela et al (2010b) found that, at high sustained loads, when steel corrosion is firstly accelerated and then allowed to run naturally, the rate of the widening of corrosion cracks does not change, but the rate of steel corrosion reduces significantly. Malumbela et al (2010b) attributed this to natural steel corrosion producing dryer products that are not easily exuded to the exterior faces of concrete.
Results by El Maaddawy & Soudki (2003), Mangat & Elgarf (1999), Malumbela et al (2010a,b) and Alonso et al (1998) indicate that the effect of the level of current density on structural behaviour is contentious. Further research to clarify this is therefore necessary.
Whilst anodes are simply steel bars that are required to corrode, various types of cathodes have been used in accelerated corrosion tests. In some research, metal bars embedded in concrete were used (El Maaddawy et al 2005b; El Maaddawy & Soudki 2003; Badawi & Soudki 2005). In others, metal bars were placed on external surfaces and inside a chloride salt electrolyte (Malumbela et al 2009; Ballim et al 2001). These bars were of different dimensions and made from different metals. The most used metals, such as stainless steel, copper and titanium, had good electrical conductivity. Rather than using bars, other researchers chose to use metal plates or mesh that covered the external faces of concrete (Azad et al 2007; Rio et al 2005; Gadve et al 2009; Fang et al 2004).
Placing cathodes inside concrete means hydroxyl ions are produced inside the concrete and then moved to the anodic steel. The rate of corrosion here is dependent on how well oxygen can penetrate the concrete, as well as how well hydroxyl ions penetrate the concrete to reach the anodic steel. When cathodes are placed externally, hydroxyl ions are no longer produced inside the concrete. It was pointed out by Poursaee & Hansson (2009) that, from an electrochemical viewpoint, this is not acceptable, as hydroxyl ions under natural corrosion are produced inside the concrete. In the situation where cathodes are placed externally, the rate of corrosion is dependent on how well hydroxyl ions can penetrate the concrete. How cathodes should be designed to better represent in-service conditions is unclear and most certainly requires further research. It is, however, reasonable to follow a recommendation by Poursaee & Hansson (2009) that they should be placed inside the concrete.
One more parameter that needs discussion in designing corrosion tests in laboratories is the type of corrosion products. Researchers have detected various corrosion products in corrosion-affected RC structures, all with different densities and volume expansion as shown in Figure 2 (Liu & Weyers 1998; Roberge 1999; Jaffer & Hansson 2009).
The type of corrosion product was found to be primarily dependent on pH and availability of oxygen (Roberge 1999; Jaffer & Hansson 2009; Broomfield 1997). These factors (pH and quantity of oxygen) are very variable and difficult to quantify in a corroding RC structure. Many researchers contend that for corrosion of steel that is embedded in concrete, ferrous hydroxide is the fundamental corrosion product (Liu & Weyers 1998; El Maaddawy & Soudki 2007; Bhargava 2006; Roberge 1999). With an increase in the supply of oxygen (especially after cracking of the cover concrete), more stable corrosion products such as haematite and magnetite are formed.
Varying procedures of accelerated corrosion tests is therefore likely to influence types of corrosion products formed. For example, when specimens are fully immersed in NaCl solution, Hussain (2010) has shown that moisture blocks the pores of concrete, and hence prevents oxygen from diffusing into the concrete to reach the anode. More soluble products, such as ferrous hydroxide, are therefore expected. In addition, when the rate of steel corrosion is high (as in accelerated corrosion tests), the rate of ingress of oxygen into the concrete might not be adequate to produce stable compounds. This helps to explain why in accelerated corrosion tests where specimens are immersed in salt solution, corrosion products that exude the concrete are often greenish-black in colour, indicating a large presence of ferrous hydroxide (Malumbela et al 2010b,c). On reaching the surface, they immediately turn reddish-brown, indicating a conversion to the more stable compounds such as haematite and magnetite. When steel corrosion is slow and concrete is drier, oxygen is expected to be in abundance to form the stable products. Reddish-brown products, indicating a large presence of stable corrosion compounds, are often found in in-service structures, as well as in laboratory specimens where steel corrosion is natural (François & Arliguie 1998; Castel et al 2003; Vidal et al 2007; Zhang et al 2009a,b; Zhang et al 2010; Malumbela et al 2010b). Since these products are of different volume densities, the rate of widening of corrosion cracks is expected to be greatly influenced by the procedure used to accelerate steel corrosion. It is important to observe that large densities belong with more soluble products. Therefore, at the same level of steel corrosion, specimens that exhibit unstable corrosion products are expected to be more severely cracked than those with more stable products. This is in agreement with results from El Maaddawy & Soudki et al (2003). On the same note, soluble products easily exude the corroding area and therefore relieve the cover concrete of applied pressure. However, drier products do not easily egress the corrosion region and hence sustain the pressure. This argument is in agreement with results from Malumbela et al (2010b) and from Alonso et al (1998). Research on the chemical composition of corrosion products from accelerated corrosion and from natural corrosion tests, and how they affect cover cracking, is needed.
As already mentioned, structural engineers and asset managers often rely on measurable parameters of corroding RC structures, such as corrosion crack widths and stiffness, to predict levels of steel corrosion, as well as their residual load-bearing capacities. This involves using relations developed by researchers such as a relation between corrosion crack widths and mass loss of steel. To confirm these relations, some researchers have measured the actual level of steel corrosion at the end of accelerated corrosion tests. This was done by removing corroded steel bars from concrete specimens, cleaning them, and measuring levels of steel corrosion as mass losses of steel or as corrosion pit depths. In real structures, however, it is uncommon for corroded steel bars to be removed from structures. Faraday's Law is therefore often used to estimate the level of steel corrosion. It is also extensively used in modelling other parameters of corroding RC structures, such as time to first cover cracking (El Maaddawy & Soudki 2007) and stiffness of corroded structures (El Maaddawy et al 2005a). To relate measurable parameters of RC structures with the level of steel corrosion accurately, the suitability of Faraday's Law to estimate the level of steel corrosion needs to be understood.
Figure 3 shows a plot of mass loss of steel measured at the end of corrosion tests with predicted mass loss of steel from Faraday's Law. The data in Figure 3 was obtained from various researchers in the literature. A summary of conditions of the experiments used by the researchers are in Table 1. As expected from the variation of conditions for accelerated corrosion from various researchers, Figure 3 shows a large scatter. The difference between mass loss of steel predicted from Faraday's Law and actual mass loss ranged from -6.7 to 23.9% with a mean of 1.3% and a standard deviation of 3.6%. Note that this excludes results from Malumbela et al (2010c) which are also shown in the figure but will be discussed in detail later. Despite the scatter, there was a trend (R2 = 0.82) that measured mass loss was linearly related to predicted loss. It is evident from the figure that at mass losses of steel above 8%, the majority of data points were below the line of equality. This indicates that at large mass losses of steel (>8%), Faraday's Law tends to overestimate the level of steel corrosion. The trend-line shows the predicted loss to be around 18% larger than the measured loss. Some researchers believe this to be caused by corrosion products building up around the reinforcing bar surface and thus forming a physical barrier to the ingress of corrosion agents (Liu & Weyers 1998; Badawi & Soudki 2005). From the previous discussion, it is expected that more soluble products which occupy larger volume will form a large barrier and hence significantly retard the corrosion process.
Despite the trend discussed above, it is worth pointing out that the measured mass loss of steel presented in Figure 3 is an average mass loss of steel over the entire corroded length of a bar. If the level of steel corrosion varies along the bar, average mass loss of steel, and hence Faraday's Law, may underestimate the maximum level of steel corrosion. Rather than measuring average mass loss of steel, some researchers opted to measure maximum pit depths (Torres-Acosta et al 2007; Torres-Acosta & Martinez-Madrid 2003). Torres-Acosta et al (2007) and Torres-Acosta & Martinez-Madrid (2003) tried to correlate maximum pit depths with average penetration depth (calculated from average mass loss). They found them to be linearly related, but maximum pit depth was about eight times larger than average penetration depth. Similar results were found by Rodriguez et al (1997). This is important information which suggests the need to evaluate the accuracy of Faraday's Law to predict maximum mass loss of steel.
Malumbela et al (2010c) researched on the relation between maximum mass loss of steel and Faraday's Law. Their corrosion process involved a current density of 189 μA/ cm2 and two different cycles of wetting of cover concrete with 5% NaCl solution, and natural drying under laboratory conditions. One accelerated process entailed four-day wetting followed by two-day drying cycles whilst in the other, cycles were all four days. They only contaminated the tensile face of RC beams with salt solution. Their target mass loss of steel from Faraday's Law was 10%. This meant 44 wetting days when the current was impressed. At the end of the test, they measured both average mass loss of steel and maximum loss.
It is clear from Figure 3 that for beams with two-day drying cycles, maximum mass losses of steel were largely greater than predicted losses. The largest loss in those beams was 12.1% compared to 10% from Faraday's Law. Despite these larger mass losses of steel, Figure 3 shows that they are still within the range of values that were observed by other researchers who measured average mass loss. However, their consistency, which did not exist in results from other researchers, points to the need to be cautious when predicting maximum mass loss of steel using Faraday's Law.
Mass losses of steel in beams with four-day drying cycles were certainly much larger than corresponding losses in beams with two-day drying cycles. The most obvious reason that can be attributed to beams with longer drying cycles having larger mass losses of steel, is that longer drying cycles could have allowed for more natural corrosion to occur because of the extended time required to reach the desired time of electrolysis. As already mentioned, for beams to have the target level of steel corrosion of 10%, beams corroded using two-day drying cycles were tested for 64 days (44 wetting days + 20 drying days). Beams tested with four-day drying cycles were, however, tested for 80 days (44 wetting days + 36 drying days). This implies that beams under the four-day drying cycle had 16 days of additional natural corrosion compared to beams under the two-day drying cycles. It was later shown by Malumbela et al (2010b) that the natural corrosion rate in beams was too low (30.4 μA/ cm2) to have resulted in the recorded large mass losses of steel in beams with four-day drying cycles. The large differences in mass losses here could be ascribed to the set-up with two-day drying cycles not allowing the complete dryness of the concrete cover at the corroded rebar depth. Therefore, after the drying period, less stable products such as ferrous hydroxide (which according to Figure 2 occupy a larger volume than dryer products) would still be available within the corrosion region. On the other hand, more stable products, such as haematite and magnetite (which occupy less volume) could have formed during the four-day drying periods. The formation of these lesser volumetric compounds could have allowed for more access of corrosion agents to the rebar, which could have led to larger corrosion rates. This notion is in agreement with discussions by Hussain (2010) on the effect of moisture variation on rate of steel corrosion.
Figure 3 clearly indicates that Faraday's Law is not adequate to predict levels of steel corrosion, particularly where sufficient drying of cover concrete is permitted. Since natural steel corrosion often occurs under drier conditions than most accelerated corrosion tests, Faraday's Law is likely to underestimate levels of steel corrosion in in-service structures. It is therefore recommended that further research be carried out to model the interaction between dryness of cover concrete and rate of steel corrosion.
Mangat & Elgarf (1999) found that, at mass losses of steel due to steel corrosion up to 7%, the level of current density had little effect on the load-bearing capacity of RC beams. However, at mass losses of 10% and beyond, load-bearing capacity of RC beams decreased significantly with increase in the level of the impressed current density. For example, at a mass loss of steel of 20%, current density of 1000 A/cm2 induced a loss of load-bearing capacity of 60% compared to 78% when a current density of 4000 μA/cm2 was used. They attributed this to a larger loss in the interfacial bond at the steel/concrete interface caused by the high corrosion rates. Contrary to findings by Mangat & Elgarf (1999), Azad et al (2007) reported that it was not the current density that caused a larger reduction in load-bearing capacities at higher levels of steel corrosion, but rather the product of current density with time. They further asserted that a higher value of corrosion current density for a lesser period of time would be as damaging as a lesser value of current density for a longer corrosion period.
Where Mangat & Elgarf (1999) and Azad et al (2007) agreed was that, at large mass losses of steel (>10%), calculated values of load-bearing capacity, using measured average mass losses of steel, had little relation with experimental results. For example, according to Mangat & Elgarf (1999), a mass loss of steel of 19% corresponded to a predicted loss in load-bearing capacity of 20%. The measured loss in the load-bearing capacity was, however, found to be 78%. Azad et al (2007) found average mass loss of steel of 1% to relate to loss in load-bearing capacity of 1.4%. The corresponding relation between mass loss of steel and theoretical load-bearing capacity varied with the level of steel corrosion. At a corrosion level of 31%, theoretical load-bearing capacity exceeded the measured capacity by 30%, but at lower levels of corrosion (around 5%) theoretical capacity was found to be similar to the measured capacity. The researchers (Mangat & Elgarf 1999; Azad et al 2007) attributed the poor predictions of ultimate capacity of beams at high mass losses of steel to losses in the bond between corroded steel bars and the surrounding concrete. They therefore developed necessary correction factors. According to Azad et al (2007), the residual load-bearing capacity of corroded RC beams should be calculated using Equations 1 and 2. In line with their experimental findings, these Equations indicate that the needed-correction-factor, a, reduces with an increase in the level of steel corrosion (it).
Mu_actual = measured capacity of teams (kN-m)
Mu_theoretical = theoretical capacity of beams based on reduced average cross-sectional area of steel (kN-m)
a = correction factor d = bar diameter (mm)
i = corrosion current density (mA/cm2)
t = duration of corrosion (days)
Torres-Acosta et al (2007) found a poor relation between average penetration depth on steel bars (calculated from average mass loss of steel), due to steel corrosion and the residual capacity of RC specimens. A cross-sectional loss of steel of 1% was found to be equivalent to a loss in capacity of 1.6%. This relation is similar to the relation found by Azad et al (2007) where average mass loss of steel was used. Torres-Acosta et al (2007), however, found a good relation (R2 ~ 1) between the load-bearing capacity and maximum pit depths. From this relation, it can be shown that a 1% maximum loss in area of steel yields a 0.6% loss in load-bearing capacity. Note that Torres-Acosta et al (2007) presented their results using radius loss instead of loss in cross-sectional area of steel. They were converted here to allow them to be compared with those from other researchers. Interestingly, the relation found by TorresAcosta et al (2007) is similar to a theoretical relation between loss of steel cross-sectional area and load-bearing capacity of RC beams developed by Ting & Nowak (1991). Even more intriguing, no correction factors, as recommended by Mangat & Elgarf (1999) and Azad et al (2007) were needed in Ting & Nowak's model. It therefore suggests that the correction factors are limited to theoretical models of load-bearing capacity which use average mass loss of steel. More importantly, it implies that the loss in bond between steel and concrete may not be the reason for the failure of the theoretical models.
Malumbela et al (2010c) showed that load-bearing capacity of corroded RC beams against maximum mass loss of steel was closely related to theoretical results from a basic model of load-bearing capacity of RC beams. This was without applying factors of bond between steel and concrete, as suggested by Azad et al (2007). Malumbela et al (2010c) further demonstrated that the use of average mass loss to predict load-bearing capacity of RC beams at high mass losses of steel will overestimate it.
Results from Torres-Acosta et al (2007) and from Malumbela et al (2010c) against those from Azad et al (2007) and from Mangat & Elgarf (2007) suggest that the load-bearing capacity of corroded RC beams is not related to the level of current density, but to the actual maximum mass loss of steel. However, more test results are needed to confirm this.
1. This paper discussed various procedures that are often used to accelerate steel corrosion in laboratory tests of RC specimens. It clearly pointed out that, to hurriedly de-passify steel, researchers should avoid adding chlorides to concrete mixes or fully immersing their samples in salt solutions. These procedures result in uniform steel corrosion that unfortunately underestimates the effects of partial surface steel corrosion, which is often observed in in-service structures. It was instead recommended in the paper that limited faces of specimens should be contaminated with chlorides. This can easily be achieved in laboratories by building ponds on surfaces to be contaminated or by selectively spraying them with chlorides.
2. To accelerate steel corrosion, continuous immersing of specimens in salt solution was shown to underestimate the rate of steel corrosion that is observed when corrosion occurs on a drier cover concrete. Since corrosion in in-service structures involves long drying periods, it was recommended that laboratory corrosion tests should also entail long drying periods. Probably more research is needed to standardise the duration of drying periods.
3. Various types of cathodes are often used when accelerating steel corrosion embedded in concrete. Placing cathodes on exterior surfaces of concrete was shown not to represent natural steel corrosion well. It was recommended that cathodes should be placed inside the concrete. Further research on this was, however, recommended.
4. The level of impressed current density to be used to accelerate steel corrosion was found to be contentious between researchers. For example, El Maaddawy & Soudki (2003) and Mangat & Elgarf (1999) found that, at the same level of steel corrosion, higher current densities cause more structural damage than lower densities, while Alonso et al (1998) and Malumbela et al (2010b) found that a lower current density caused more structural damage. It was therefore recommended that this should be researched further.
5. Except for results from Mangat & Elgarf (1999), many researchers found the load-bearing capacity of corroded RC specimens to be related to actual loss in area of steel and not to the level of current density used. Torres-Acosta et al (2007) and Malumbela et al (2010c) further showed that load-bearing capacity of corroded RC beams was related more to maximum mass loss of steel than to average loss. More data to confirm this is, however, needed.
The support of the Concrete Materials & Structural Integrity Research Unit (CoMSIRU) at the University of Cape Town is greatly acknowledged.
Almusallam, A A, Al-Gahtani, A S, Aziz, A F & Rasheeduzzafar, F 1996. Effect of reinforcement corrosion on bond strength. Construction & Building Materials, 10(2): 123-129. [ Links ]
Alonso, C, Andrade, C, Rodriguez, J & Diez, J M 1998. Factors controlling cracking of concrete affected by reinforcement corrosion. Materials & Structures, 31: 435-441. [ Links ]
Andrade, C & Alonso, C 2001. On-site measurements of corrosion rate of reinforcements. Construction & Building Materials, 15: 141-145. [ Links ]
Azad, A K, Ahmad, S & Azher, S A 2007. Residual strength of corrosion-damaged reinforced concrete beams. ACI Materials Journal, 104(1): 40-47. [ Links ]
Badawi, M & Soudki, K 2005. Control of corrosion-induced damage in reinforced concrete beams using carbon fiber-reinforced polymer laminates. Journal of Composites for Construction, 9(2): 195-201. [ Links ]
Ballim, Y & Reid, J C 2003. Reinforcement corrosion and deflection of RC beams - An experimental critique of current test methods. Cement & Concrete Composites, 25: 625-632. [ Links ]
Ballim, Y, Reid, J C & Kemp, A R 2001. Deflection of RC beams under simultaneous load and steel corrosion. Magazine of Concrete Research, 53(3): 171-181. [ Links ]
Bhargava, K, Ghosh, A K, Mori, Y & Ramanujam, S 2006. Analytical model for time to cover cracking in RC structures due to rebar corrosion. Nuclear Engineering & Design, 23(6):1123-1139. [ Links ]
Broomfield, J. 1997. Corrosion of steel in concrete. London: E & FN Spon. [ Links ]
Cabrera, J G 1996. Deterioration of concrete due to reinforcement steel corrosion. Cement & Concrete Composites, 18: 47-59. [ Links ]
Cairns, J, Du, Y & Law, D 2008. Structural performance of corrosion-damaged concrete beams. Magazine of Concrete Research, 60(5): 359-370. [ Links ]
Castel, A, Vidal, T, Francois, R & Arliguie, G 2003. Influence of steel-concrete interface quality on reinforcement corrosion induced by chlorides. Magazine of Concrete Research, 55(2): 151-159. [ Links ]
El Maaddawy, T, Chahrour, A & Soudki, K 2006. Effect of fiber-reinforced polymer wraps on corrosion activity and concrete cracking in chloride-contaminated concrete cylinders. Journal of Composites for Construction, 10(2): 139-147. [ Links ]
El Maaddawy, T & Soudki, K 2003. Effectiveness of impressed current technique to simulate corrosion of steel reinforcement in concrete. Journal of Materials in Civil Engineering, 15(1): 41-47. [ Links ]
El Maaddawy, T & Soudki, K 2007. Model for prediction of time from corrosion initiation to corrosion cracking. Cement & Concrete Composites, 29(3): 168-175. [ Links ]
El Maaddawy, T, Soudki, K & Topper T 2005a. Analytical model to predict nonlinear flexural behaviour of corroded reinforced concrete beams. ACI Structural Journal, 102(4): 550-559. [ Links ]
El Maaddawy, T, Soudki, K & Topper T 2005b. Long- term performance of corrosion-damaged reinforced concrete beams. ACI Structural Journal, 102(5): 649-656. [ Links ]
Fang, C, Lundgren, K, Chen, L & Chaoying, Z 2004. Corrosion influence of bond in reinforced concrete. Cement & Concrete Research, 34: 2159-2167. [ Links ]
Frangois, R & Arliguie, G 1998. Influence of service cracking on reinforcement steel corrosion. Journal of Materials in Civil Engineering, 10(1): 14-20. [ Links ]
Gadve, S, Mukherjee, A & Malhotra, S N 2009. Corrosion of steel reinforcements embedded in FRP wrapped concrete. Construction & Building Materials, 23: 153-161. [ Links ]
Hussain, R R 2010. Effect of moisture variation on oxygen consumption rate of corroding steel in chloride-contaminated concrete. Cement & Concrete Composites, doi:10.1016/j. cemconcomp.2010.09.014. [ Links ]
Jaffer, S J & Hansson, C M 2009. Chloride-induced corrosion products of steel in cracked-concrete subjected to different loading conditions. Cement & Concrete Research, 39: 116-125. [ Links ]
Jang, B S & Oh, B H 2010. Effects of non-uniform corrosion on the cracking and service life of reinforced concrete structures. Cement & Concrete Research, 40: 1441-1450. [ Links ]
Liu, Y & Weyers, R E 1998. Modelling the time-to-corrosion cracking in chloride-contaminated reinforced concrete structures. ACI Materials Journal, 95(6): 675-681. [ Links ]
Malumbela, G, Alexander, M G & Moyo, P 2010a. Interaction between corrosion crack width and steel loss in RC beams corroded under load. Cement & Concrete Research, 40: 1419-1428. [ Links ]
Malumbela, G, Alexander, M G & Moyo, P 2010b. Serviceability of corrosion-affected RC beams after patch repairs and FRPs under load. Materials & Structures, doi 10.1617/s11527-010-9630-9638. [ Links ]
Malumbela, G, Alexander, M G & Moyo, P 2010c. Variation of steel loss and its effect on flexural capacity of RC beams corroded and repaired under load. Construction & Building Materials, 24: 1051-1059. [ Links ]
Malumbela, G, Alexander, M G & Moyo P 2011. Model for cover cracking of RC beams due to partial surface steel corrosion. Construction & Building Materials, 25: 987-991. [ Links ]
Malumbela, G, Moyo, P & Alexander, M G 2009. Behaviour of RC beams corroded under sustained service loads. Construction & Building Materials, 23: 3346-3351. [ Links ]
Mangat, P S & Elgarf, M S 1999. Flexural strength of concrete beams with corroding reinforcement. ACI Structural Journal, 96(1): 149-158. [ Links ]
Masoudi, S, Soudki, K & Topper T 2005. Post-repair fatigue performance of FRP-repaired corroded RC beams: experimental and analytical investigation. Journal of Composites for Construction, 9(5): 441-449. [ Links ]
Poursaee, A & Hansson, C M 2009. Potential pitfalls in assessing chloride-induced corrosion of steel in concrete. Cement & Concrete Research, 39(5): 391-400. [ Links ]
Rio, O, Andrade, C, Izquierdo, D & Alonso, C 2005. Behaviour of patch-repaired concrete structural elements under increasing static loads to flexural failure. Journal of Materials in Civil Engineering, 17(2): 168-177. [ Links ]
Roberge, P R 1999. Handbook of corrosion engineering. New York: McGraw-Hill. [ Links ]
Rodriguez, J, Ortega, LM & Casal, J 1997. Load carrying capacity of concrete structures with corroded reinforcement. Construction & Building Materials, 11(4): 239-248. [ Links ]
Ting, S & Nowak A S 1991. Effect of reinforcing steel area loss on flexural behaviour of reinforced concrete beams. ACI Structural Journal, 88(3): 309-314. [ Links ]
Torres-Acosta, A A & Martinez-Madrid M 2003. Residual life of corroding reinforced concrete structures in marine environment. Journal of Materials in Civil Engineering, 15(4): 344-353. [ Links ]
Torres-Acosta, A A, Navarro-Gutierrez, S & Teran-Guillen, J 2007. Residual flexure capacity of corroded reinforced concrete beams. Engineering Structures, 29: 1145-1152. [ Links ]
Tuutti, K 1980. Service life of structures with regard to corrosion of embedded steel. In: Performance of concrete in marine environment, ACI SP-65, Detroit, US: American Concrete Institute, pp 223-236. [ Links ]
Vidal, T, Castel, A & François, R 2007. Corrosion process and structural performance of a 17-year-old reinforced concrete beam stored in a chloride environment. Cement & Concrete Research, 37: 1551-1561. [ Links ]
Yoon, S, Wang, K, Weiss, J & Shah S 2000. Interaction between loading, corrosion, and serviceability of reinforced concrete. ACI Materials Journal, 97(6): 637-644. [ Links ]
Yuan, Y & Ji, Y 2009. Modeling corroded section configuration of steel bar in concrete structure. Construction & Building Materials, 23(6): 2461-2466. [ Links ]
Yuan, Y, Ji, Y & Shah, S P 2007. Comparison of two accelerated corrosion techniques for concrete structures. ACI Materials Journal, 104(3): 344-347. [ Links ]
Zhang, R, Castel, A & François, R 2009a. Serviceability limit state criteria based on steel-concrete bond loss for corroded reinforced concrete in chloride environment. Materials & Structures, 42(10): 1407-1421. [ Links ]
Zhang, R, Castel, A & François, R 2009b. The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment. Cement & Concrete Research, 39(11): 1077-1086. [ Links ]
Zhang, R, Castel, A & François, R 2010. Concrete cover cracking with reinforcement corrosion of RC beam during chloride-induced corrosion process. Cement & Concrete Research, 40(3): 415-425. [ Links ]
Contact details:
Department of Civil Engineering
University of Botswana
Private Bag 006'
UB Post, Gaborone
E: email@example.com
Contact details:
Department of Civil Engineering
University of Cape Town
Private Bag X3
South Africa
E: email@example.com
Contact details:
Department of Civil Engineering
University of Cape Town
Private Bag X3
South Africa
E: firstname.lastname@example.com
PR0F PILATE MOYO is an Associate Professor lr the Department of Civil Engineering at the University of Cape Town (UCT). He holds a BSc (Eng) from theUniversity of Zimbabwe, an MSc (Eng) from the University of Newcastle upon Tyne, and a PhD from Nanyang Technological University. He is part of the eadershlp of CoMSIRU (Concrete Materials & Structural Integrity Research Unit) at UCT. His research area is structural health monitoring and condition assessment of structures. He regularly acts as a specialist consultant to industry on vibration serviceability problems, dynamic analysis and dynamic based assessment of structures.
DR GOITSEONE MALUMBELA is a Senior Lecturer at the University of Botswana. He graduated with a BSc Honours in Civil Engineering from the University of Missouri Rolla, USA, in 1999, an MSc (Engineering) from the University of the Witwatersrand in 2003 and a PhD from the University of Cape Town in 2010. His research nterests are in the performance of corrodec and repaired reinforced concrete structures.
PROF MARKALEXANDER Is Professor of CM Engineering at the University of Cape Town (UCT). He holds BSc (Eng), MSc (Eng), and PhD degrees from the University of the Witwatersrand, Johannesburg. His teaching and research interests are in cement and concrete materials engineering. He is part of the eadershipofthe UCT CoMSIRU (Concrete Materials & Structural Integrity Research Unit) and is currently the President of RILEM. He acts as a specialist consultant to industry and the profession on concrete materials problems. He is a Fellow of the South African Institution of Civil Engineering, the South African Academy of Engineers, and the University of Cape Town.


text:
READING - A city man was arrested Friday and charged with sexually assaulting a disabled woman he drove to the Special Olympics.
Joseph T. Lombardo, 59, of 806 Joan Terrace, Reading, faces charges of rape, involuntary deviate sexual intercourse, indecent assault, and indecent exposure for the acts he allegedly committed against the 48-year-old mentally disabled Sinking Spring woman starting in 2009 and ending in 2011.
According to a press release from Berks County Detectives, Lombardo is the owner of Life Coach Companion, a transportation business for the mentally disabled. The victim was one of his clients whom he took to several times to the Special Olympic events, police said.
Lombardo allegedly had inappropriate contact with the woman at his home and in the Life Coach Companion vehicle, police said.
An investigation of Lombardo began in September 2012 after Sinking Springs Police received a sexual assault complaint. A forensic interviewer from Children's Alliance Center of Berks County and a psychologist interviewed the 48-year-old victim and determined she was unable to give consent to sexual activity, police said.

subset: commoncrawl


text:
Adele, LMFAO, Justin Bieber Win 2012 NRJ Awards
If the results of this weekend's NRJ Awards in Cannes are any indication, French music audiences love to party rock, but they also appreciate a quality ballad. Adele and LMFAO captured two awards each, while Justin Bieber took home the 2012 NRJ Award of Honor.
Adele won International Song of the Year for 'Someone Like You' and International Revelation of the Year. Despite losing both of those categories to Adele, LMFAO still managed to walk away with two awards. The high-octane duo won International Group/Duo of the Year and 'Party Rock Anthem' captured Music Video of the Year, beating out Katy Perry's 'Last Friday Night' and Lady Gaga's 'Born This Way.' Redfoo also lit up the stage with a performance of the song, though his bandmate Sky Blu was not present.
Not all of the winners made it to France for the ceremony, but Bieber attended, decked out in a light blue suit with a retro, slicked-back haircut. Ace Showbiz reports that he told the crowd, "Thank you to everyone here. I love you guys." He also posted on Twitter, "I never thought I would ever get out of Stratford and now I'm celebrating in France. Never gets old. ALWAYS grateful! #Ilovemyfans."
Shakira also received an NRJ Award of Honor for her long and successful career. Rihanna beat Britney and Beyonce to win International Female Artist of the Year, while Mika knocked off Pitbull to take International Male Artist of the Year.
Complete list of 2012 NRJ Award winners:
Francophone Revelation of the Year: Keen V
International Revelation of the Year: Adele
Francophone Male Artist of the Year: M Pokora
International Male Artist of the Year: Mika
Francophone Female Artist of the Year: Shy'm
International Female Artist: Rihanna
Francophone Song of the Year: 'A nos actes manques' - M Pokora
International Song of the Year: 'Someone Like You' - Adele
Francophone Group/Duo of the Year: Simple Plan Feat. Marie-Mai
International Group/Duo of the Year: LMFAO
Music Video of the Year: 'Party Rock Anthem' - LMFAO
NRJ Award of Honor: Justin Bieber and Shakira
NRJ Award of Diamond: Mylene Farmer


text:
At MacNair Travel Management, we understand how challenging it can be to effectively manage your travel program. That's why when we decided to redesign our website, we made its focus YOU. The new site is a place you can rely on to find answers to all of your travel management questions. We've developed tools that assess, teach and inform. In our blog, we will keep you up-to-date on the latest trends, explain how they impact you and continue to provide educational information about controlling costs, policy consideration, balancing organizational needs with traveler satisfaction and more.
The first stage of our redesign is complete. When you visit you will immediately notice streamlined menus, simple navigation and easy access to useful tools and information. The site is mobile friendly - you can access and use the site from any mobile device. Take a look around, bookmark the site, check back often and connect with us on LinkedIn, Twitter, and Facebook to receive updates as new content is added. The site will continue to evolve as we continue to develop it.
We've also redesigned our newsletter, InFlight. You're reading it now! Just like the website, the focus of the newsletter is YOU. We will be providing relevant information that highlights trends, changes and other important travel-related information that can or will impact your organization. Look for it each month.
We hope you're as excited as we are about these changes. We welcome your feedback and input.


text:
Inspirational guidebook to 50 challenging routes for mountaineers, scramblers, hillwalkers and fell runners, many long enough to backpack over 2 days, especially in winter (12 to 25 miles). Classic walking routes and novel approaches across Scotland from Galloway to the Outer Hebrides in widely differing wild landscapes. With customised OS mapping
•50 challenging walking or backpacking routes across Scotland, from 12 to 25 miles long, many with optional scrambles •several routes feature optional approaches by mountain bike or kayak •includes an index of 270 summits and ranges featured in the book


text:
Tsunami MPEG DVD Author Pro features an easy-to-use interface and robust features. MPEG DVD Author Pro offers high-speed frame level editing, dual layer support, Smart Rendering, slideshow creation with Dolby Digital sound. DVD AUTHOR PRO provides you with quality tools that enables you create studio-like DVDs with surprising ease.
Available beginning in late September 2005 at retail stores across North America at an MSRP of $99.95, boxed versions of MPEG DVD Author Pro include a free 90-day trial version of Video Encoder XPress. Tsunami MPEG DVD Author Pro is also available for download from www.tmpg-inc.com.


text:
ExPatriatePen wrote:Thanks but no thanks Mr. Ratner. One million dollars a year is not to be considered "...working with *you*"
I don't know the present/future value calculation off the top of my head, but a guesstimate would be ~ $6M per year could fund $150M worth of 30 year municipal bonds. $6M isn't a huge figure considering the hundreds of millions per year being bandied about by Ratner.
Add the $90M Rendell has already said he would release to shut everybody up and $50M for naming rights and this is done.


text:
As I finished dinner, I went up to my room to begin my work on tomorrow's lesson. Perhaps it's the fact that it gets so dark so early now, but the entire neighborhood felt so quiet, almost lonely. As I entered the room, and began fumbling for the light, I could hear the muted sounds of a trumpet. Since I live next door to a middle school, at first I believed it must have been a kid in band practicing, or a mariachi band playing for a party. As I listened some more to the muffled sounds, I knew the player was too good to be a middle school kid. Also, it was far too late in the evening for some kid to still be hanging out on campus.
I went to the bathroom window, opened it, and pressed my ear against the screen. I could easily hear someone playing a sad, slow trumpet in the middle of the field. The echoes against the walls of the school made the song sound so melancholy and beautiful. I went back downstairs and outside to the backyard, under the pretense of letting the dog out. Once downstairs, the sound did not echo as well and I went back upstairs.
I went out on the balcony to hear the trumpet player. I'm not sure why, but it was the most beautiful thing in the entire world. A single person, standing in the middle of a field, in the middle of the night, creating such pretty noise. The sounds of the city made such a lovely accompaniment: the barking dogs (not just mine), the cars zooming by, the sirens off in the distance, the white noise of the jet engines as they headed to LAX.
As I listened, I went from feeling like a privileged audience of one to feeling like an intruder. Here I was, hidden by the shadows of the house, listening to this person perform such an intimate act. I felt like I had stumbled upon something I was not supposed to be aware of. Still, the notes carried by the evening air fell upon my ears, and I felt a joy usually reserved for the final movement of Beethoven's 9th, the feel of grass in my feet or the sun on my face, or a cozy bed with the dog.
Thanks, whoever you are, for reminding me that the world is still a beautiful, wonderful, awesome place.
When, on an autumn evening, with closed eyes
Posted by Srta. García on 11.09.2009
/ Comments: (0)


text:
Nonisothermal Plug Flow Reactor
Application ID: 1404
This example considers the thermal cracking of acetone, which is a key step in the production of acetic anhydride. The gas phase reaction takes place under nonisothermal conditions in a plug-flow reactor. As the cracking chemistry is endothermic, control over the temperature in the reactor is essential in order to achieve reasonable conversion. When the reactor is run under adiabatic conditions, the model shows how the conversion of acetone can be affected by mixing the reactant with inert. Furthermore, it is illustrated how to affect the conversion of acetone by means of a heat exchanger supplying energy to the system.
The example details the use of the predefined Plug-flow reactor type in the Reaction Engineering interface and how to set up and solve models describing nonisothermal reactor conditions. You will learn how to model adiabatic reactor conditions as well as how to introduce heat exchange. The model also demonstrates how to import thermodynamic data the the CHEMKIN format.
This model example illustrates applications of this type that would nominally be built using the following products:
however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
The combination of COMSOL® products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries. Particular functionality may be common to several products. To determine the right combination of products for your modeling needs, review the Spezifikationstabelle and make use of a free evaluation license. The COMSOL Sales and Support teams are available for answering any questions you may have regarding this.


text:
by Matt Dalby, sports information graduate assistant
MILLEDGEVILLE, Ga. – Senior student-athlete Tyler Mattix (Snellville, Ga.) has been named Georgia College Athlete of the Week for his performance in the NCAA Southeast Regional Championships, as announced by the Sports Information Department Tuesday afternoon.
The Bobcat harrier saved one of his best races for last, blistering the 10K course in just 32:41. His time put him in 17th place, good for the first men's All-Region cross country honors in school history.
Mattix also rewrote the Georgia College record book, now holding the top 10K time in school history after topping teammate Dan Horseman's (Cohutta, Ga.) 2010 NCAA Southeast Regional time by 10 seconds.
With his second GC Athlete of the Week award, Mattix joins women's soccer student-athlete Ashley Veilleux (Monroe, Ga.) and men's tennis player Jerome Leborgne (Coordimanche, France) as the only two-time recipients thus far this year.
The Georgia College Department of Athletics, two-time winners of the PBC Commissioner's Cup, sponsors 10 varsity athletic programs at the NCAA Division II level. As a Division II program, Bobcat Athletics prides itself on balancing the life of the student-athlete, evidenced by the teams' multiple appearances in post-season competition as well as documented academic success and community-service involvement. Sign up at www.twitter.com/BobcatSports and www.facebook.com/gcbobcats for up-to-the-minute reports, and visit www.GCBobcats.com for more information, and to nominate your favorite former Bobcats and Colonials to the GC Athletics Hall of Fame.


text:
Beneath The Ashes
Underworld: Beneath the Ashes DLC now on XBL
Tomb Raider: Underworld DLC Beneath the Ashes is now available on XBL. The first of two packs to be released, Beneath the Ashes sends Lara back to Croft Manor, where she discovers crypts used by her father to hide a deadly power source. It'll run you 800 MS Points ($10), and includes six new costumes […]
Beneath The Ashes headlines
Tomb Raider: Underworld -Beneath the Ashes DLC dated for Xbox 360
Tomb Raider: Underworld DLC Beneath the Ashes – delayed earlier in the month – has been scheduled for a February 24 release. Lara's Shadow, the next batch of content, will arrive on March 10 as a 1.07Gb download. Bug fixes will be included in a patch about the same time, and are listed after the […]
Tomb Raider DLC delayed thanks to "technical issue"
Eidos just confirmed that tomorrow's planned Tomb Raider Underworld DLC has been delayed. "An unexpected technical issue means that Beneath the Ashes will not be available to download on 10th February as planned," said a spokesperson. "We apologize for this delay and we are doing everything we can to bring you this exciting new content […]
Tomb Raider: Underworld DLC shown in movie
Eidos has released a showcase video of Beneath the Ashes, the soon-to-be-released DLC for Tomb Raider: Underworld, and very swish it looks to. The featurette takes a look at environments and gameplay elements in the content. Watch it on Shacknews. It's out on February 10. A second episode releases on March 10.
Tomb Raider: Underworld DLC date confirmed
The first part of Xbox 360's exclusive Tomb Raider: Underworld DLC – titled Beneath the Ashes – will ship on February 10, Eidos said today. The second installment, Lara's Shadow, will follow on March 10. According to the press release, "Beneath the Ashes sends Lara back to the remains of Croft Manor where she uncovers […]


text:
Military, Products, Services
By By Andrew Drwiega, Military Editor | December 12, 2012
Send Feedback
During times of austerity it is good to see that the occasional commitment by government to an asset that has played a significant role in a variety of activities since being commissioned into active service in 1998.
HMS Ocean, currently the largest Royal Navy warship afloat until the arrival of the Queen Elizabeth class carriers in the latter part of this decade, will receive a £65-million upgrade taking around 15 months. Although designed to support amphibious landing operations, by helicopter and landing craft, the warship has been active throughout most of her service to date.
This will be the ship's second period of down time following a refit in 2007. This should take her through to the end of service life scheduled for 2018. As a helicopter carrier, HMS Ocean can take a variety of up to 18 aircraft onboard.
One of HMS Ocean's early roles was as part of the Royal Navy Task Force in Operation Telic against Iraq in 2003. During the deployment the ship was home to the following: 10 Sea King HC4s from 845 NAS, six Gazelle AH1s from 847 NAS, and six Lynx from 847 NAS. These aircraft would subsequently be involved in the land effort taking on Saddam Hussain's forces in the battle for Basra (ref: Armed Action, by Lt. Com. James Newton DFC).
The role that HMS Ocean played in Operation Unified Protector, the mission against Col. Gaddafi's regime in Libya, included acting as a base for the 4 Regiment Army Air Corps' Apache attack helicopters. Although playing a relatively small part in contrast to the total air campaign, the Apaches had a very high success rate during their attacks on land-based targets in a high threat environment. Eventually up to six AAC Apaches operated from the ship. This was the first time that UK Apaches had deployed operationally from a maritime home base.
Other helicopters to use the warship include Sea King Mk 7 airborne surveillance and control helicopters (SKASaC) of 857 Naval Air Squadron (NAS) and Lynx Mk 7 of 847 NAS. It is expected that Merlin AW101 helicopters will operate from HMS Ocean once she returns from refit—and when the aircraft have been transferred from RAF to Commando Helicopter Force control.
Recently HMS Ocean was moored in the River Thames to act as home to RN and AAC Lynx helicopters that were part of the aerial protection force guarding London's 2012 Olympic Games. The upgrade is the largest to be undertaken by Devenport's Royal Dockyard in over 20 years. The refurb will involve more than 300 specialists from main contractor Babcock, together with an expected 300 additional jobs from up to 70 contractors.Related: Military News


text:
...is Slowly Reappearing
Story by Ken Burton, U.S. Fish & Wildlife Service
There was a time when pirates sailed past it. In the 1700s, it was a backdrop for Revolutionary War naval skirmishes. It once supported a small town, with cattle, a post office and a school. That was before Poplar Island, located in the Chesapeake Bay 34 miles south of Baltimore, began to disappear.
Today, Poplar Island is back, and better than ever: in the 1800s, it amounted to around 1,000 acres. By 1990, erosion had cut the island into three separate chunks of land and squeezed it to less than 10 acres. Today, thanks to a successful restoration effort led by the U.S. Army Corps of Engineers, it has returned to 1,140 acres and may grow by another 570 acres before the project is finished.
Using soil dredged from the Baltimore shipping channel, workers are steadily rebuilding the island and restoring its habitat. When work on Poplar Island is complete, half the acreage will be turned into wetlands and half, uplands – complete with trees. The island will be maze of smaller islands, ponds, channels and marshes. Some 40 million cubic yards of dredge material will be protected by 35,000 feet of containment dikes.
Jason Miller, a biologist with the U.S. Fish and Wildlife Service Chesapeake Bay Field Office in Annapolis (CBFO), is focusing on two parts of the newest version of Poplar Island: submerged aquatic vegetation and wildlife management.
Submerged aquatic vegetation (SAV), also called bay grass, supports a diverse community of fish, shellfish, invertebrates and waterfowl. Miller spends a lot of time monitoring the return of submerged vegetation in Poplar Island's tiny new harbor. Many of the plants are returning on their own, while a partner group from Anne Arundel Community College has pitched in and helped with seeding, adding a bit of insurance.
Miller, who works in close partnership with the Corps,
When the Baltimore shipping channel is being dredged, barges operate 24 hours a day, 7 days a week to move 2 million yards of fill, from September through March of each year. The work began in 1998 and Scott Johnson, the man who manages the project for the Corps, estimates that work won't be finished until 2020, at a total cost of about $400 million, with 75 percent of the cost borne by the Federal government and the remaining 25 percent, by the State of Maryland.
What's new at Poplar Island ?
For more information:
Army Corps of Engineers Baltimore District


text:
Matheny's selfless approach a perfect fit for Cardinals
ST. LOUIS -- In the years after concussions prematurely ended his playing career, Mike Matheny began to ponder possible future pursuits. It was in that thought that Matheny found a key piece of clarity.
He did not know what he was going to do. He only knew how he was going to do it.
ST. LOUIS -- In the years after concussions prematurely ended his playing career, Mike Matheny began to ponder possible future pursuits. It was in that thought that Matheny found a key piece of clarity.
He did not know what he was going to do. He only knew how he was going to do it.
Matheny dabbled in other business ventures between the time his playing career ended and the Cardinals offered him a managerial job. But largely, he consumed himself in learning more about a servant-leadership model that had long intrigued him. Think of it as a hierarchy structure in which the pyramid is flipped upside down.
Matheny read books about the concept. He conversed with leaders of large local corporations, who already subscribed to the model. They gave him more books to read. The benefits of the model -- one in which the leader chooses to serve, not to rule, by putting others first -- were immediately obvious to Matheny.
That's because they were familiar.
"It struck me that I had done some of this as a leader in a catching role," Matheny said. "Out there in the clubhouse, I wasn't more important than anyone else. But as a catcher, there is more responsibility, more people you have to work with. My whole point of being in that uniform was to make my pitchers' job easier and to make them better. That's really what kept me around."
Convinced that the model would work in any sector, Matheny promised himself that he would adopt it once he settled on what to do next. It was during his ongoing studies that the Cardinals called, and he accepted the new career direction. Matheny believed managing would offer him the perfect platform from which to put the servant philosophy into practice.
"This model takes nothing away from how you compete," Matheny said. "But it just creates an atmosphere where you make other people better. When you make other people better, and you set your mind on how to focus on someone outside yourself, you create something pretty special."
It was early in Matheny's first Spring Training as manager when he sought out Mitchell Boggs, looked him in the eye and convinced Boggs that he believed in his ability. Matheny told Boggs that he had the talent to be great, which is why he planned to give the right-hander a key late-inning role.
Boggs went on to lead the National League in Holds (34) and rank sixth with a 2.21 ERA. Teammates later said they saw a direct connection between Boggs' 2012 emergence and that February conversation.
"Mike has a way with words," Wainwright said. "He's an uplifter. He's an encourager. From a moment of weakness where you begin to doubt your ability or question your role on the team, then you have the guy who is putting out the starting lineup every day tell you that you have a place and that you don't have anything to worry about. All of a sudden, you're confident and get right back in a rhythm."
It is not a foolproof formula, of course, as Boggs' 2013 troubles reinforced. But this idea of loyalty and the execution of a model that emphasizes positive reinforcement have thus far been distinguishing characteristics of Matheny's two-year managerial tenure.
He gave Boggs every opportunity to right himself after a disastrous start to the season and tried the same recently with Edward Mujica. In a move that was widely criticized publicly, Matheny sent Mujica to the mound for a save situation in Milwaukee on Sept. 20. He saw the risk, but also believed in the greater reward.
"We are one pitch away from potentially getting our closer in a good frame of mind," Matheny said. "Is that a good risk to take? Absolutely. In my mind, that is the right thing to do."
That's why Matheny stuck with Lance Lynn when all was going wrong in August. It is why, upon meeting John Axford after a late-season trade, he reminded the former Brewers reliever that he still had that 2011 potential. It's why Matheny has shown such little hesitancy in thrusting young players into critical roles.
He believes whole-heartedly in the organizational process. And he believes deeply in his players.
"It's not something that I put on my list, that I need to be loyal to these guys," Matheny explains. "What's at the top of my list is to do the right thing. That's really what I've tried to do. You're always risking by going against how something might appear, but we always realize the potential reward."
Matheny has been intentional in creating an environment where his door would always be open and his conversations concern as much the personal as the professional. He makes it a point to ask about families and faith, hoping that through it all, players see him on the bottom of that inverted-pyramid model.
This approach is what veterans and rookies alike have credited for the smooth assimilation of so many young players this season. Anticipating that the big league club would get substantial contributions from its up-and-coming prospects -- though certainly not expecting to use as many rookies (20) as they have -- Matheny set the groundwork for their arrival during his Spring Training conversations.
"I didn't know him that well, but he showed an effort to get to know the guys during camp," said rookie Seth Maness, a non-roster invitee in Spring Training. "Even when we would get sent back down, he would call us in and talk to us and be very professional. He made it seem possible that you could get back up here soon."
"I know a lot of people don't put much value in it, but to me, I spend a lot of Spring Training trying to build a rapport and a relationship with these guys," Matheny explained. "One, it's the right thing to do. And if we can get the communication going where I understand them and they understand me, then they feel a little more comfortable when they show up. That gives them a better chance to just do what they need to do."
What those rookies have done is pick up 36 wins, make 52 starts and take over the roles of closer and cleanup hitter after late-season adversity hit. The culmination was the Cardinals' first division title since 2009, a year in which the organization had just 10 starts from rookies.
"He was the perfect fit for this job and the transition that this team was going through," Chris Carpenter said of Matheny. "Again, I don't think you could have done any better job with these young kids and controlling the veterans and putting them both together to go out and get the best out of all of us. He should be rewarded for that and acknowledged for that. He's done a fantastic job."
The journaling, like the absorption of his leadership model, came long before Matheny assumed Tony La Russa's chair. Matheny once read a John Adams biography that detailed miles of microfilm of letters that Adams and his wife, Abigail, left to their children. That spurred Matheny on to create a journal for each of his five kids.
He keeps his own personal one, too.
Then, there are the pages and pages of baseball notes -- some in the notebooks he carries around, others digitally saved on an iPad. Some entries are a few sentences in length. Some are paragraphs long. Matheny keeps them for future reading and reflection.
He has chosen to refrain from revisiting his 2013 entries until the season closes.
"I really don't want to," Matheny said. "We live so much in yesterday that up until I get here [at the ballpark] to get my workout in, I'm still living in yesterday. I think you have to have that separation that that's gone, now what do I have to do? I don't think it's time to reflect yet."
When Matheny does take the time to absorb the significance of this season, perhaps he'll recognize his place in it. Though quick to deflect praise and content in shouldering fault, Matheny should also be credited with preserving an organizational culture while achieving at a high level.
He is the first Cardinals manager since Gabby Street in 1930-31 to lead the team to the postseason in his first two seasons. Outside of Street and Matheny, only nine other Major League managers have matched that level of immediate success.
"I feel like he's done a very good job, especially given the roster he's had to work with," general manager John Mozeliak said. "It's been an unusual year with injuries. We've certainly had to go with a younger team. But I think the way he has managed that and the environment that he has created, he's done an outstanding job."
Certainly, Matheny had the benefit of stepping into a favorable situation. It's rare for rookie managers to assume the reins of a team coming off a World Series championship. But that didn't mean that everything was stable.
Last year, Matheny helped usher the organization through some key departures. This season featured regular doses of adversity, the byproduct of which was a larger-than-anticipated reliance on young talent. All the while, though, Matheny strove not to stray from service, and he's proud of the environment that has fostered.
"When I have people from other very respected organizations, who have been around the game a long time, tell me that this group as a whole is representing themselves in a way that's different but in a positive way, that makes me proud," Matheny said. "I told this to [owner] Bill DeWitt that there is a culture here, and a long-standing expectation with the Cardinals, that people have high talent, are highly motivated, are driven to excellence, but also they are people that care to do things the right way."
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB.


text:
Video: How can investors review the background of a stockbroker or investment adviser?
How can investors review the background of a stockbroker or investment adviser?
Also available at KansasCityLaw.tv and The Kueser Law Firm's website.
In this video, Jason M. Kueser discusses how investors can research the background of stockbrokers, financial advisors, and Registered Investment Advisers (RIAs). Background information related to stockbrokers and financial advisors can be obtained using FINRA's BrokerCheck tool. Background and other information related to Registered Investment Advisers (RIAs) can be found on the Investment Adviser Public Disclosure website. In addition to these sites, there are various third-party sites/services that provide information related to stockbrokers, financial advisors, and investment advisers.
This video is provided for informational purposes only and nothing contained herein is or should be constituted as legal advice. If you have questions related to any legal topic, you should consult with an attorney and should not rely solely upon information provided via the internet.
The choice of an attorney is an important one and should not be based solely upon advertisements such as this website. Past results afford no guarantee of future results. Every case is different and must be judged on its own merits. *Any information submitted via this website may not be secure and/or confidential. Merely contacting this firm does not establish an attorney-client relationship.


text:
Public Service, Regulatory, Services
By By Ernie Stephens | September 1, 2012
Send Feedback
A couple of years ago, I was asked by one of Rotor & Wing's sister publications to write an article on how aircraft are painted. So, I called a relatively small outfit with a fine reputation for such work to see if they wanted to be featured in it. To make a long story short, I left two messages with a live employee, plus one on their answering machine, before finally talking to the owner. After explaining that I wanted to build the entire article around his business, which amounts to four pages of free, global advertising, his reply was one of pure disinterest. "Well, uh, I'll call you back," he mumbled. But he didn't. The next call was to the people at a much larger company. They immediately jumped at the chance to show off their aircraft painting facility.
It perplexed me why such a little outfit with very little (if any) money for advertising in a major aviation magazine would ignore such an opportunity, while a large company with enough cash to buy all of the ad space it wants couldn't get me to their plant fast enough.
Now, enter police departments that have aviation units.
Make no mistake about it, when I call the hangars of law enforcement agencies asking them if I can write something up about them, I always get an enthusiastic response from the men and women who take helicopters into the sky, as well as the people who turn wrenches on them. But, like most everything in a public service organization, people higher than line personnel have to give their approval before a cop-turned-writer can talk to anyone. And while I'm perfectly fine with that, it's during those requests for approval that the wheels tend to fall off. Law enforcement agencies, both big and small, seem very ho-hum when it comes to free, positive press about the fine work their helicopter unit does.
Case in point: As I was looking for a police department to feature in the July 2012 issue, it occurred to me that a certain agency, which shall remain nameless, would make a great subject for a cover story. And as far as law enforcement readership goes, that issue is seen by more winged officers than any other, because it's the one we also hand out at the Airborne Law Enforcement Association convention each year.
So, I phoned that department's hangar, got the usual enthusiastic response from the rank-in-file, and followed their instructions for requesting approval from their press information officer (PIO). For the next several weeks, I got nothing—not even a "We have your request and will get back to you."
With time running out, I called another operation. Once again, the folks at the hangar were quite eager to be spotlighted, but I also got weeks of dead silence from their PIO. (Truth be told, this happens more times than not, regardless of the size of the agency.)
With time pretty much gone, I phoned the office of Chief Teresa Chambers of the United States Park Police. She was in a meeting, but I was asked to shoot her an e-mail with my request, which I did. Less than 45 minutes later, I found a reply from Chambers herself. The first lines read, "Ernie: Yes, of course, PLEASE pursue this story. Our guys have SO many compelling stories to tell..." It was followed by her own list of some of the things they have done, as well as a "cc" line showing she had simultaneously repeated her blessing all the way down the chain of command to the hangar level. Five days later the story was done, complete with archival video footage of a recent rescue, which you can see on our web page at www.rotorandwing.com.
Now, in all fairness, the PIOs of the first two agencies finally ended up giving me approval to write about their aviation sections. But unfortunately for those two outfits, copies with the USPP on the cover were already being printed. And as Chambers had said, their adventures were excellent!
So, my question is a simple one: In a world where public service budgets are being cut, and people are questioning the bang for the buck they get from police aviation, why does it take so long for those people who sit between the crews and the chief to see the value in a feel-good article about an element of their own department? It amounts to free advertising, as well as a public "atta boy" for jobs well done!
Chambers apparently gets the worth of positive press, and how it might someday serve as documentation that her aviation assets truly earn their keep, even at a time when public funding can be a bit thin. But I'm also betting she knows how morale went through the ceiling at the hangar when they saw how eager she was to have Rotor & Wing shine a light on their fine work.
By the way, there are some other agencies out there that respond to article requests quickly, even without starting at the top. And to them I say thanks! To the people I spoke with at those two agencies back in April and May, I know it wasn't you who let the clock run out. And to them and everyone else, I won't give up on trying to tell your stories.


text:
Site Map
Thank you for coming to Save On, we really want to assist you when it comes to your mortgage and insurance needs.
Our goal is to ensure that you are always given the highest quality advice (where selected) and service, in respect of your borrowing and insurance requirements.
We would like to reaffirm that, as professional financial advisers, we will endeavour to ensure that your mortgage and or insurance applications are processed quickly and efficiently and that you are kept fully informed about their progress.
Finally, we would like to make you aware that we are authorised and regulated by the Financial Conduct Authority.
Thank you for your custom.
Yours faithfully,
Save On
* Unsecured and Buy to Let Loans are unregulated products and as such are not subject to Financial Conduct Authority regulations and no protection is given under the Financial Services Compensation Scheme.
Save On Mortgages the No. 1 choice
Save On Limited includes: save-on-mortgages, cheap-remortgages, low-cost-mortgage, low-cost-remortgage, low-cost-buytolet, low-cost-debtconsolidation, cheap-mortgages, save-on-loans, save-on-remortgages, save-on-insurance, save-on-buytolet, save-on-debt, save-on-homeloans, save-by-remortgaging, the-mortgage-broker, online-mortgage-broker, internet-mortgage-broker, no-fee-mortgage-broker, consolidating-debt, save-on-group, save-on-finance, whole-market-mortgage-broker, mortgages, remortgages, mortgage-brokers, buildings-contents-insurance, self-employed-mortgage, travel-insurance, private-medical-insurance, pet-insurance
As a No Fee Whole of Market Mortgage Brokers we offer a wide range of lenders including:
and many more . .
Authorised and regulated by the Financial Conduct Authority, Save On Mortgages is a trading style of Save On Limited


text:
ASU ROTC Unit Tops in Region
September 20, 2013
Angelo State University Det 847 has been named the best medium-size detachment in the Southwest Region for the second consecutive year. It is the fourth time in the last seven years Det 847 has earned this honor.
As the winner of the region, which includes 14 medium-sized detachments in 11 states from Mississippi to Hawaii, ASU's 110-member detachment next will compete against winners of the three other regions in the national Headquarters AFROTC Right of Line competition later this year.
Detachments are selected for the High Flight honor based upon the cadets' university activities, community participation, military preparedness and success in meeting AFROTC goals in academics, fitness and retention. Arizona State University's detachment won in the Southwest Region's large-sized category, while the University of Arkansas' detachment was named the region's best among small-sized detachments. ASU's Detachment 847 previously won regional honors in 2007, 2010 and 2012.
"This award is a tribute to the hard work and dedication of the cadre and staff working at the detachment," said Lt. Col. Pedro Matos, detachment commander since July 12. "It also highlights the effort, camaraderie and determination of our cadets."
As the largest student organization on campus, the detachment's cadets build the annual Homecoming Bonfire, lead the Homecoming Parade and the ASU Veterans Day Vigil, and conduct a Junior ROTC Drill Meet for area high school programs. The cadet's color guard has supported more than 40 events in San Angelo, including the flag retreat at Fort Concho National Historic Landmark.
"Much of our success is because of the community, the university and Goodfellow Air Force Base," Matos said. "Without that support, we couldn't do half of what we do here."
ASU cadets who successfully complete ROTC service are commissioned as second lieutenants in the U.S. Air Force. Detachment 847 was formed in 1971.
More information on ASU's ROTC program is available online at www.angelo.edu/dept/rotc/ or by calling 325-942-2036.


text:
My Will (Honeymoon Is Over) Lyrics by Nas
Nas Lyrics
My Will (Honeymoon Is Over) Lyrics
[Intro: Nas]
Aiyyo whattup niggaz?
Fresh off the honeymoon
The honeymoon's over
Fresh off Vaca (Yea, Yea)
I'm jet-laggin', still jet-laggin'
But this just a preview
Let's get it on again y'all
[Verse 1: Nas]
I designed it - rhymed it - flow classic
You askin' - who am signed with?
The real deal is 'Ill Will', stay scomit
Why's drama when other artists pay homage
You hatin any rapper I do a song with
"What's wrong with Nas helpin' crews get stronger"
You selfish, wantin' me to yourself
But Prophets need help too, y'all see Nas get insulted
I ride for the real shit, High as the Lock's get melted
Twelve Years, givin' you nuttin' but big moments
How can 'Murda Inc' not wanna f*ck wit
The top hustler - R.O.C. crusha
Nas a legend 'fore 'BIG & Pac' left us
Bubbled wit 'Dr. Drizze', You heard it on +Makaveli+
Sayin'-> "Nas is ring leader, brings Ether, brings heater"
Your dream teamer scream, "He's the Supreme Teacher"
Similar to anybody you know
Oh, I created, cremated, body that flow
Anyone you think is f*ckin' wit me
Better be Vets - better be 'Ra', better be 'Kool G' or 'KRS'
Better be 'LL' or 'Slick' or them
Neva put me in the 'Top Ten' BITCH!
It's disrespect to the life that burnt the verses
Or nigga writes who comes first
It's the 'Ice Cube' 'MC Shan' them type dudes
So B.E.T.'s list was wrong, don't get me wrong
I did chill in the throne alone so long
This is my +My Will+
[Outro: Nas]
Yea, Escobaro Cigars, that's how we doin' it
Aiyo Quan welcome to the game
Shot-out to Ill Will (This is my +My Will+)
Bravehearts stand up, whuttup Scarface
Whuttup Tre Williams (This is my +My Will+)
Ill Will '05, what y'all know 'bout that?
Queens, Queens I know you miss me
I gotchu, I gotchu Queens, New York stand up
Ahha, I gotchu baby, let's do it again
Back to:
Nas Lyrics
Top Hits
One Hit Wonders
TV Themes
Song Quotes
Lyrics On Demand
All lyrics are property and copyright of their respective authors, artists and labels.
All lyrics provided for educational purposes only.
Please support the artists by purchasing related recordings and merchandise.


text:
Windows 8 XAML Primer is a fast-paced introduction to XAML for Windows 8 developers who are already proficient C# coders. It introduces you specifically to the world of XAML development for Windows 8 apps in a practical, hands-on way - so you'll be building apps from the very first pages.
Building on your existing C# knowledge, you're introduced to XAML from the ground up - what it is, what it does, and why it's important in Windows 8 development. You'll quickly learn how to use XAML efficiently within Visual Studio. You'll find practical coding quickstarts to get your XAML hands-on knowledge up to speed, so you'll be ready to progress to your more advanced Windows 8 programming projects with ease.
If you're confident in your .NET coding abilities but the jump to XAML and C# in Windows 8 is giving you pause, then Windows 8 XAML Primer will have you coding Windows 8 projects in its first pages, and you'll be ready to start your own apps by the time you're finished.
What you'll learn
How to code Windows 8 apps with XAML and C# with your own hands.
Confidence in using XAML within Visual Studio 2012 efficiently.
How to databind to both data sources and other elements.
About the many presentation controls and panels that XAML provides for you, what they do and how to use them to best effect.
How inbuilt resources such as styles, templates and dictionaries can make your code more fluid, terse, and efficient.
How to develop storyboards using the Visual State Manager to create and control XAML animations within your user interface.
Who this book is for
This book is for new Windows 8 developers who have experience with C# and now want a firm foundation in XAML as they transition to the new world of Windows 8 app development.


text:
Denver Broncos linebacker Von Miller tried to cheat the NFL's drug-testing program with the help of the person assigned to collect his urine sample, according to an ESPN report.
Miller, who was second in the league with 18 1/2 sacks last season, had been suspended for the first six games -- inexplicably, two more games than the typical NFL penalty for that transgression.
According to the report, Miller's representatives and the players union were prepared to fight his initial four-game suspension but backed off when they became aware Miller and the collector worked together to help the player avoid a failed choice.
Sources told ESPN the Miami-based collector was "star-struck."
The scheme was uncovered when a second collector learned Miller was not in the city where his collection was to have taken place.
Bengals fans revolt against Katy Perry song as team anthem
Jon Jones survives biggest test -- Alexander Gustafsson -- at UFC 165
College football players show support for NCAA changes by marking gear


text:
Looks like you are using an old version of Internet Explorer - Please update your browser
Waltke's overall approach to the creation account and the interpretation he adopts in this commentary is not much different from what he has previously written on this subject.
This volume is the most recent in a spate of publications presenting multiple views on Genesis and creation. This one focuses on what the Bible says about the length of the creation days.
The subject of this work is the relationship between science and Christianity. Four views are presented and the representatives of each respond to every other presentation.
In Genesis Unbound, Sailhamer adopts a unique view of the creation account in order to harmonise it with the claims of modern science.
No results found in .
Answers in Genesis is an apologetics ministry, dedicated to helping Christians defend their faith and proclaim the gospel of Jesus Christ.


text:
Origin of chikki in Lonavala
Lonavala was so named because of the word 'lenya' which means caves in Marathi. There are many rock-cut caves, which surround Lonavala. It was Shri Maganlal Agarwal (the fourth generation of Maganlal Agarwal's family is now running the chikki business) who brought chikki to Lonavala more than 125 years ago. His great grandson, Ashutosh Agarwal told me that it all started when Shri Maganlal began selling 'gurdana', a mixture of jaggery and groundnuts in a huge sack to the laborers who were laying tracks on the Khandala–Pune railway line. (Opened to traffic in 1858) He used to stand with the big sack, next to the railway line, literally outside where the Maganlal's main shop stands now in the market street on the east side and sold the 'gurdana'. 'Gurdana' is rich in protein and iron and the laborers used to consume it for the instant energy. Later, the simple 'gurdana' graduated to the groundnut chikki and over the years other chikki varieties were introduced. Nevertheless, the whole and crushed groundnut chikki are still Maganlal's bread and butter product making up for 70% of the total chikki varieties sold.
Choosing the right Chikki
Chikki are available in more than 30 varieties. So choose the one whose basic ingredient you like. They have cashew, groundnut (crushed and whole), chana, kesar pista, badam, coconut, rajgira, kurmura, til, dry fruits mixed and permutations and combination of all these.
- Some chikki which I thought were unique (may not be tasty) were ginger, honey peanut and mint crush.
- The price per kilo starts at Rs 80 for groundnut, til, chana chikki to Rs 520 for kesar pista.
- Some chikki like strawberry, mango, chocolate would be made without jaggery and would have mava and fruit pulp in them.
- The calorie conscious need not worry, there are "low calorie and sugar free" chikki like Groundnut (whole and crush) available.
- Jaggery is not added to some chikki like cashew as it becomes very dark and does 'not look good' in Ashutosh Agarwal's words.
- With so little differentiation between different brands, it is very difficult to make out what makes a good quality chikki.
- A good and fresh chikki will be crisp and not soft. The chikki sold on the trains may generally not be fresh so do look up the manufacturing date.
- The color of the chikki should medium brown (groundnut), i.e. not too dark or light. If it too light then the manufacturer has used less jaggery to save on costs and if it too dark then it has been in the kadhai for a longer time than required.
- The manufacturer might try and save on the costs of expensive ingredients like cashews, badam, pista etc by putting less of it in the chikki. You can make it out by just looking at the chikki as the distance between two cashew pieces will be more and there will be more sugar/liquid glucose added.
- Some manufacturers may use materials of low grade quality (cashews, groundnuts, almonds etc).
As I have mentioned before, there are around 30-40 brands of chikki sold in Lonavala. So which one is the best? I generally buy chikki from three stores. Maganlal, National and A-1. Why these three. Firstly because the quality of chikki sold is better than the others. Secondly, one of them is the inventor of the Lonavala chikki and so is bound to be good (Maganlal) and thirdly, because these three brands were the ones that my grandfather, uncle and father used to buy for many many years, so check on word of mouth for recommendations.
And how do I decide which of these three I would buy the chikki from. This would depend on the time I have to buy chikki. When there was no expressway and the Bombay-Pune Asiad buses used to halt for a break at Lonavala, I used to quickly run across to A-1, as it was the closest of the three to the Asiad bus stand and buy the chikki. If I was going to change a train at Lonavala, then I used to buy it from Maganlal/National, as they are closer than A-1 to the railway line. If I was staying in Lonavala and had lots of time, I would buy it from National, Maganlal or A-1 in that order.
Maganlal also has many franchises and that is why you will see lots of Maganlal shops all over Lonavala. Thus, if you want to buy it from the original Maganlal, it is located on the east side (the other side of the Mumbai- Pune highway) and is between the National Chikki Mart and Coopers fudge shop.
Not just chikki
For all those who don't like chikki, Lonavala has more to offer…you can buy other stuff like fudges (try the Coopers chocolate walnut fudge at a princely sum of 600 Rs a kilo and go there early as it gets over pretty quickly), farsans, chivdas (try the corn flake chivda at National Chikki Mart), barfis and other stuff like pickles, honey, wafers, syrups and squashes which you will anyway get in Bombay.
And by the way, I am writing this chomping on three kinds of chikki… whole groundnut, crushed groundnut and cashew, all bought from the original Maganlal.