An Investigation on Water Quality Control with Functional Gels

(1)利用功能凝胶提高生物硝化速率的研究开发了一种利用固定化技术提高硝化速率的方法。采用N-异丙基丙烯酰胺（NIPAAm）作为功能凝胶，其根据温度的变化可逆地收缩和膨胀，例如，一种热敏凝胶。研究了凝胶的体积相变对硝化活性的影响。将硝化菌固定在凝胶中，并在25 ~ 35 ℃的温度范围内进行循环热处理，与固定在凝胶中的硝化菌在25、28和35 ℃恒温条件下的硝化活性进行比较。在循环热操作条件下，由于温敏型生物膜的体积相变引起的“泵效应”，硝化速率急剧增加 关于我们 L. (2)电响应功能凝胶体积相变过程动力学研究以2-丙烯酰胺-2-甲基丙磺酸（PAMPS）和甲基丙烯酸（PMAA）为原料合成了电响应功能凝胶，考察了它们在电场作用下的弯曲特性。弯曲速度与电场强度成正比。这两种凝胶响应相当迅速的电刺激，与热和pH值响应功能凝胶相比。凝胶的弯曲在几秒至几分钟内朝向负电极发生。进一步的研究应着眼于利用电响应凝胶不仅作为致动器，即，在水处理系统中用作化学阀，而且在废水处理系统中用作微生物的固定化介质。(3)化学阀的开发和控制通过NIPAAm与甲基丙烯酸合成pH响应性功能凝胶，以检查凝胶的溶胀特性并开发可以控制曝气池中的空气流速的化学阀。所提出的化学阀可以控制蒸馏水中空气的流量。然而，在污水中的pH响应功能凝胶溶胀和收缩与大pH刺激轻微。因此，在具有高离子强度的溶剂如污水中，难以通过化学阀控制空气的流速。这表明应合成新的pH响应功能凝胶，否则应提出新型化学阀。少

(1) Application of Functional Gels to Increase in Rate of Biological NitrificationA method to increase the nitrification rate with an advantage of the immobilization technique was developed. N-isopropylacrylamide (NIPAAm) was adopted as a functional gel which shrinks and swells reversibly depending on the change of temperature, e.g., a thermo-responsive gel. Effects of the volume phase transition of the gel on the nitrification activity were studied. Nitrifiers were immobilized in the gel, and pellets of it were incubated under a cyclic thermal operation between 25 and 35 ﾟC.It was compared with the nitrification activity by nitrifiers immobilized in the gel under three isothermal operations at 25,28 and 35ﾟC.In conclusion, the nitrification activity is enhanced by utilization of the thermo-responsive gel. Under the cyclic thermal operation, a drastic increase in the rate of nitrification occurs due to a "pumping effect" caused by the volume phase transition of the thermo-responsive ge … More l.(2) Kinetic Studies on Volume Phase Transition Processes of Electro-Responsive Functional GelsElectro-responsive functional gels synthesized by 2-acrylamide-2-methylpropane sulfonic acid (PAMPS) or methacrylic acid (PMAA), were examined on bending characteristics under an electric field. The bending speed was proportional to the field strength. Both gels responded quite rapidly to electro-stimuli, in comparison with thermo- and pH-responsive functional gels. Bending of the gels took place toward the negative electrode within several seconds to minutes. Further studies should aim at utilization of the electro-responsive gels not only as an actuator, i.e., a chemical valve, in water treatment systems, but also as an immobiklzation medium for microorganisms in waste water treatment systems.(3) Development and Control of a Chemical ValvepH-responsive functional gels were synthesized by NIPAAm with methacrylic acid, in order to examine swelling characteristics of the gels and to develop a chemical valve which can control a flow rate of air in an aeration tank. The proposed chemical valve could control the flow rate of air in distillled water. However in sewage the pH-responsive functional gels swelled and shrank slightly with large pH-stimuli. Therefore it was difficult to control the flow rate of air by the chemical valve in a solvent with high ionic strength like sewage. This indicates that new pH-responsive functional gels should be synthesized, otherwise new types of chemical valves should be proposed. Less