O/A/O组合工艺在浆染废水处理中的应用

以如皋常青某印染厂废水处理中心为例，介绍了O／A／O组合工艺处理浆染废水的工程设计。设计处理规模为1000m^3／d，进水COD为1200mg／L，处理后出水达国家一级排放标准。实践证明这是一种处理可生化性较差、难降解废水的行之有效的工艺。     

Selective photocatalytic oxidation of steroid estrogens in presence of saccharose and ethanol as co-pollutants

The potential of the photocatalytic oxidation to selectively oxidise steroid estrogens, β-estradiol and 17α-ethynylestradiol, in the presence of saccharose and ethanol as co-pollutants was clearly demonstrated. The alkaline media conditions remained the most beneficial for the PCO regardless the presence of co-pollutants under consideration. Saccharose appeared to be the more powerful competitor than ethanol. The influence of the co-pollutants is explained by their competition for the adsorption sites and also scavenging of the OH-radicals.     

Biodegradability of organic nanoparticles in the aqueous environment

Synthetic nanoparticles have already been detected in the aquatic environment. Therefore, knowledge on their biodegradability is of utmost importance for risk assessment but such information is currently not available. Therefore, the biodegradability of fullerenes, single, double, multi-walled as well as COOH functionalized carbon nanotubes and cellulose and starch nanocrystals in aqueous environment has been investigated according to OECD standards. The biodegradability of starch and cellulose nanoparticles was also compared with the biodegradability of their macroscopic counterparts. Fullerenes and all carbon nanotubes did not biodegrade at all, while starch and cellulose nanoparticles biodegrade to similar levels as their macroscopic counterparts. However, neither comfortably met the criterion for ready biodegradability (60% after 28 days). The cellulose and starch nanoparticles were also found to degrade faster than their macroscopic counterparts due to their higher surface area. These findings are the first report of biodegradability of organic nanoparticles in the aquatic environment, an important accumulation environment for manmade compounds.     

碘淀粉比色法测定环境样中微量碘

试验了碘的倍增反应用于微量碘的测定，用淀粉指示剂显色，最大吸收峰位于６２０ｍｍ，摩尔吸光系数可达１×１０５Ｌ·ｍｏｌ－１·Ｃｍ－１．０～６μｇ碘／１０ｍｌ符合比耳定律，可用于盐湖水、矿泉水、油田水和食盐、海产品中微量碘的测定．     

马铃薯淀粉生产废水综合利用技术研究

将马铃薯淀粉生产中的蛋白液通过蛋白提取和茵细胞提取技术,制成饲料蛋白,从而降低马铃薯淀粉生产废水中的有机物含量,减轻废水对环境的污染,且得到利用价值高的饲料蛋白,实现淀粉生产废水的循环利用.该技术解决了淀粉生产废水污染水环境这一制约马铃薯淀粉产业发展的瓶颈问题,实现节约水资源和循环利用水的目的.     

Computer aided injection moulding process analysis of polyvinyl alcohol-starch green biodegradable polymer compound

This study aims to investigate the injection moulding processability of polyvinyl alcohol (PVOH) blending with starch as biodegradable polymer compound. The PVOH-starch polymer compound can be used to produce environmental friendly plastic products. In this study, the injection moulding processability of PVOH-starch compound was computational analyzed by Moldflow^® software. A name tag article design was chosen to determine the appropriate processing parameters of PVOH blending with 50 wt.% (PPV55) and 60 wt.% (PPV46) of starch. The processing behaviour for both compositions of PVOH-starch compounds was characterized according to injection temperature and pressure, volumetric shrinkage and frozen layer fraction. Moldflow^® simulation outcomes exhibited that PPV55 required a higher injection pressure than PPV46. Meanwhile, the simulation outcomes also showed that the volumetric shrinkage of PPV55 is higher than PPV46. Both PPV46 and PPV55 require at least 20 s holding time to achieve stable production.     

Properties of Starch/PVA Blend Films Containing Citric Acid as Additive

Starch/polyvinyl alcohol (PVA) blend films were prepared successfully by using starch, polyvinyl alcohol (PVA), glycerol (GL) sorbitol (SO) and citric acid (CA) for the mixing process. The influence of mixing time, additional materials and drying temperature of films on the properties of the films was investigated. With increase in mixing time, the tensile strength (TS), elongation (%E), degree of swelling (DS) and solubility (S) of the film were equilibrated. The equilibrium for TS, %E, DS and S value was 20.12 MPa, 36.98%, 2.4 and 0.19, respectively. The mixing time of equilibrium was 50 min. TS, %E, DS and S of starch/PVA blend film were examined adding glycerol (GL), sorbitol (SO) and citric acid (CA) as additives. At all measurement results, except for DS, the film adding CA was better than GL or SO because hydrogen bonding at the presence of CA with hydroxyl group and carboxyl group increased the inter/intramolecular interaction between starch, PVA and additives. Citric acid improves the properties of starch/PVA blend film compared to glycerol and sobitol. When the film was dried at low temperature, the properties of the films were clearly improved because the hydrogen bonding was activated at low temperature.     

Accessibility of starch to enzymatic degradation in injection-molded starch-plastic composites

Most of the starch in starch-polyethylene-co-acrylic acid (EAA)-polyethylene (PE) composites prepared by injection molding was not accessible to starch-hydrolyzing enzymes. Even when these composites were treated with enzyme in the presence of Triton X-100 for 96 h, little starch hydrolysis was observed. However, when the starch-plastic material was pulverized, both the extent and the rate of starch hydrolysis increased dramatically, with about 70% hydrolysis of the starch within 18 h. Reactions carried out for up to 96 h showed that, while the enzyme was active, the reaction reached a plateau, achieving a total of 80% starch hydrolysis. Fourier transform infrared (FTIR) spectroscopy revealed that only starch, and not EAA or PE, was affected by enzyme in pulverized samples. Results indicated that while 80% of the starch in these composites was transiently inaccessible, perhaps due to EAA and PE forming an impermeable barrier to the enzyme, the other 20% remained inaccessible to enzymes. Also, the rate of starch digestion as determined by solubilized reducing sugar correlated with the particle size of the pulverized material, suggesting that a large available surface area is critical for rapid starch degradation in such composites.The mention of firms names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over the firms or similar products not mentioned. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, marital status, or handicap.     

Effect of Starch Granule Size on Viscosity of Starch-Filled Poly(hydroxy ester ether) Composites

The effect of starch granule size on the viscosity of starch-filled poly(hydroxy ester ether) (PHEE) composites was characterized using size-fractionated potato starch, as well as unfractionated starches (rice, corn, wheat, and potato). Potato starch was separated using an air classifier into four particle size fractions: <18 m, 18-24 m, 24-30 m, and >30 m. The starch was dried to a moisture content of 0.5% to minimize moisture effects on composite rheology. PHEE and potato starch were extruded with starch volume fractions of 0.46 and 0.66. Stress relaxation, frequency and strain sweep, and temperature-dependence measurements were carried out. Although small variations in viscosity were seen with the different potato starch fractions, differences were not significant at a volume fraction of 0.46. Viscosity differences between the different particle size fractions were more pronounced at a volume fraction of 0.66. The temperature dependence could be described by an Arrhenius relation, with an apparent activation energy of 84 kJ/mole. At a volume fraction of 0.46, the starch/PHEE viscosities increased in the order potato starch < wheat starch corn starch < rice starch.     

淀粉接枝阳离子絮凝剂的制备及性能研究

主要利用化学方法对环氧氯丙烷和胺类进行阳离子改性获得阳离子醚化剂,然后与碱化后的淀粉接枝制得一种絮凝性能良好的有机高分子阳离子絮凝荆,并对所得产品作了絮凝性能实验。由实验得知该絮凝剂对悬浮细小颗粒有很好的去除效果,如高岭土溶液（1g／L）产生矾花时间较短,加入絮凝剂后搅拌3min左右即可产生明显絮体,且絮体较大,静置后透光率达90％以上。