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991.
降解性高分子材料的研究与开发现状 总被引:3,自引:0,他引:3
论述了光降解、生物降解和光-生物降解高分子材料的类型、性能及应用,总结了存在的问题,并提出了发展方向和建议。 相似文献
992.
将油酸酰氯和丙氨酸在碱性溶液中反应制备N-油酰基丙氨酸. 考察了N-油酰基丙氨酸作为润滑油添加剂对HVI350矿物基础油的生物降解性能的影响, 并采用四球摩擦磨损试验考察了N-油酰基丙氨酸在HVI350矿物基础油中的摩擦磨损性能. 结果表明, N-油酰基丙氨酸作为矿物油添加剂能大大提高矿物油生物降解性, 表现出一定的抗磨减摩性能, 并且具有优良的抗腐蚀性和防锈性, 是一种环境友好型的多功能润滑油添加剂. 相似文献
993.
Bi Shi Qiang He Kai Yao Wen Huang Qing Li 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(10):1154-1159
Two fungal strains, effective in converting valonea (Quercus aegilops) tannins into ellagic acid (EA), were isolated from soil contaminated by valonea tannins, and were tentatively identified as Aspergillus niger and Candida utilis. Properties of EA accumulation by the two isolates from valonea tannins' fermentation were studied. Both the strains preferred sucrose to glucose as the additional carbon and energy source. The most suitable concentrations of valonea tannins in fermentation media for EA accumulation by A niger and C utilis were 5.0 and 9.0 g dm?3 with EA yields of 12.1 and 8.9% (w/w), respectively. The optimal temperature for the two strains was 28 °C, while the preferred pH values of the fermentation media were 4.5–5.0 for A niger and 4.8–5.2 for C utilis. The tannin tolerances of A niger and C utilis were adapted to 20 and 25 g dm?3 by gradually increasing the concentrations of valonea tannins in the culture media. The adapted strain of A niger was able to completely degrade 20 g dm?3 valonea tannins with an EA yield of 14.3% in 9 days. Meanwhile, the adapted strain of C utilis decreased the valonea tannins' level from 25 to 9.1 g dm?3 with an EA yield of 11.48%. The degradation ability of A niger came from tannase whose activity in the medium was 63 U cm?3 at the ninth day of fermentation, and that of C utilis was due to both tannase and polyphenol oxidase (PPO) whose activities were 32 U cm?3 and 29 U cm?3 at the ninth day. The coculture of both the adapted strains could completely degrade 25 g dm?3 valonea tannins in only 7 days with a remarkably increased EA yield (21%). The activities of tannase and PPO of the coculture at the seventh day were 66 U cm?3 and 47 U cm?3 respectively, which proved the synergistic effect of the two enzymes on valonea tannins' degradation and EA accumulation. Copyright © 2005 Society of Chemical Industry 相似文献
994.
白腐菌Panus conchatus降解稻草木素机理研究──(三)木素降解产物低分子部分芳香酸类化合物的结构特征 总被引:5,自引:2,他引:3
利用色-质联用技术分析了稻草木素经由腐菌Panusconhatus生物作用后的木素降解产物中低分子酸性组分的主要化合物及其结构。结果表明此组分中大部分是芳香族化合物,通过质谱对其主要的11种化合物的结构进行了分析,发现它们主要成分是紫丁香酸,香草酸和对羟基苯甲酸及其衍生物,证实木亲生物降解过程发生木余例键Cα-Cβ键氧化断裂;另外,发现其中有相当数量的对羟基苯甲酸衍生物具有缩聚型结构,它们来源于木素结构中“核心”结构部分。根据各个化合物的相对含量计算出愈钢木基:紫丁香基:对羟基本基比例为6.1:1:2.7。证实木亲生物降解过程中本素的愈疮木基与对羟苯基结构单元优先降解,这结果与过去有关电镜和木素降解产物高分子部分的研究结果是一致的。 相似文献
995.
介绍了光-生物降解PP餐饮具的制备,用红外光谱和力学性能衰变的方法评价其生物降解引发过程。光-生物降解作用的研究结果表明,PDPⅢ和Ⅳ降解母料添加剂是此类餐饮具生物降解引发过程的有效引发剂,而此类餐饮具具有初始力学性能优良,环境降解作用显著(羰基指数值提高达中国国家标准),价格低廉和符合食品卫生要求等较优的综合使用性能。 相似文献
996.
WANGYong LIJian CHENXiaoyao 《武汉理工大学学报(材料科学英文版)》2005,20(2):12-14
Natural water absorbent konjac flour participates in synthesizing biodegraded and polyurethane foamed drape, which is used to release urea slowly. The experimental results indicate that the slowly-releasing velocity of urea nitrogen and the degrading velocity of the drape can be controlled by regulating the thicknesses of drapes , the amount of konjac flour and the water content . In addition, the biodegradability of the drape was investigated by buryinng the specimens in earth afterwards, and results show this drape can be degraded naturally. 相似文献
997.
微生物技术在石油开采中的应用 总被引:6,自引:2,他引:4
简要阐述了微生物采油技术的发展概况,论述了微生物在油层中的生物降解作用、驱油机理和现场施工方式,对微生物的生存环境和油藏的筛选条件进行了详细描述,并作了相应的物理模拟试验。试验结果表明微生物采油技术可以有效地提高采收率,具有起好的发展前景。 相似文献
998.
Qingling Zeng Yongmei Li Guowei Gu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(12):1841-1847
BACKGROUND: The synthetic estrogen 17α‐ethinylestradiol (EE2) is of great environmental concern. Batch experiments were conducted to investigate the removal of EE2 by activated sludge under anaerobic conditions with or without nitrate. The effect of temperature on EE2 removal was also estimated. RESULTS: No biodegradation of EE2 was observed in the absence of nitrate; owing to sorption onto the activated sludge, the overall removal EE2 rate was 62%; the sorption was fitted to both Freundlich and linear sorption models; the sorption rate decreased with the increase temperature. In the presence of nitrate, the overall removal rate of EE2 was greater than 97% after 72 h, mostly from biodegradation (95%); the biodegradation could be described by first‐order reaction kinetics with average rate constant of 0.0344 h?1; increasing temperature enhanced the rate constant and the removal rate could be as high as 96–98% in the temperature range 10–30 °C. CONCLUSION: EE2 was removed by activated sludge under anaerobic conditions. In the absence of nitrate, the removal of EE2 was a result of sorption onto activated sludge. In the presence of nitrate, biodegradation was the dominant process for EE2 removal. Higher temperature improves biodegradation rate, but reduces the sorption of EE2 onto activated sludge. Copyright © 2009 Society of Chemical Industry 相似文献
999.
Ranjith Jayasekara Greg T Lonergan Ian Harding Ian Bowater Peter Halley Gregor B Christie 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(4):411-417
A system has been developed for studying the biodegradation of natural and synthetic polymeric material. The system is based on standard methods developed by the European Committee for Standardisation (CEN TC 261) (ISO/DIS 14855) and the American Society of Testing Materials, ‘ASTM Standard Test Method for Determining Aerobic Biodegradation of Plastic Materials under Controlled Composting Conditions’ (ASTM D 5338‐92). A new low‐cost compost facility has been used which satisfies the requirements of these standards. The system has been automated for data collection and has been run under the conditions specified by the standards. In the system, cellulose, newspaper and two starch‐based polymers were treated with compost in a series of 3 dm3 vessels at 52 °C and under conditions of optimum moisture and pH. The degradation was followed over time by measuring the amount of carbon released as carbon dioxide. © 2001 Society of Chemical Industry 相似文献
1000.