Another more asymptotically efficient sieving method for the same problem is the sieve of Atkin. HPC is used as a sieving matrix for DNA separations by capillary and microchip electrophoresis. Durum milling is a complex procedure involving repetitive grinding and sieving. Filters use sieving, adsorption, ion exchanges and other processes to remove unwanted substances from water. Through wet milling, sieving, and solvent-extraction, oat beta-glucans can achieve up to 95% extraction purity. The sand can be kept clean by sieving or washing out with water and drying. During the sieving process an aspiration system removes the dust and chaff. The commercial production of guar gum normally uses roasting, differential attrition, sieving, and polishing. Quality began to improve in the 12th century through better grinding and sieving. They carry heavy bags of mud with their heads to designated sieving and washing sites. A favored explanation is kinetic sieving. Some success has been achieved with the use of cement mixers and bulk sieving. The grain could then be further cleansed by sieving. Amplitude and sieving time are set digitally and are continuously observed by an integrated control-unit. These primes will be the basis for sieving.