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971.
972.
柠檬酸生产废水处理技术 总被引:8,自引:0,他引:8
分析了柠檬酸生产废水的来源及水质特性,综述了厌氧生物法、厌氧-好氧生物组合法、乳状液膜法等在柠檬酸废水处理中的应用,介绍了中和废水回用和利用柠檬酸发酵废液开发糖化酶制剂的技术。 相似文献
973.
Richard Gattin Alain Copinet Celine Bertrand Yves Couturier 《Journal of Polymers and the Environment》2001,9(1):11-17
The degradation of starch- and polylactic acid-based plastic films by microorganisms extracted from compost was studied in a liquid medium. The various degradation products produced were measured throughout the duration of the experiment, and total carbon balances were estimated. For an easily biodegradable material, the evolution of the way carbon repartitioned between different degradation products was quite similar whatever the experimental condition or the type of substrate. On the other hand, for a resistant material exposed to these microorganisms, the nature of the biodegradation depended strongly on the experimental conditions. In the latter case, a differential scanning calorimetry analysis confirmed the importance of the applied norm on the state of the residual material. The consequences for improved methods of estimation of biodegradability of these materials are discussed. 相似文献
974.
Ahmed E. Bishara Habib I. Shaban Hamad Al-Adwani Sami H. Ali 《Journal of Polymers and the Environment》2001,9(4):137-147
A novel copolymer system has been synthesized using methyl hydroquinone diacetate (MHQDA), 1,4 naphthalene dicarboxylic acid (1,4 NDCA), and polybutylene terephthalate (PBT) using the melt polymerization technique. The optimum kinetic parameters pertinent to this system are reported in this study. A simple second-order reaction sequence summarizes catalyzed and uncatalyzed reactions between MHQDA, 1,4 NDCA, and PBT. The kinetic parameters for the copolymerization reaction were determined using a new second-order model. This technique was used to compute the moles of acetic acid generated in the polymerization process. The model was compared to that of the experimentally determined data. Close comparison (percentage error of less than 5%) was obtained between the experimental and theoretical data. The kinetic data support block copolyester formation. The thermal data also supports formation of block polymers. 相似文献
975.
Antoine Longieras Jean-Baptiste Tanchette Damien Erre Christian Braud Alain Copinet 《Journal of Polymers and the Environment》2007,15(3):200-206
Commercial poly(lactide) degradation was studied in an inert solid medium simulating compost conditions, with the aim to achieve
a complete carbon balance of the polymer degradation. The mineralisation rate at the end of the test was compared to those
obtained for poly(lactide) degradation in compost. It was shown that the mineralisation rate after 45 days of degradation
was quite lower in inert solid medium than in compost but the standard deviation of data was enhanced. A protocol for both
extraction and quantification of the carbon included in the different degradation by-products was proposed and the carbon
balance of the polymer degradation was followed during the test with a satisfactory accuracy. The non-degraded PLA material
was recovered during the test, hence the evolution of the glass transition temperature and the molecular weight was followed.
A two-step degradation mechanism was highlighted in inert solid medium, showing the fundamental role of abiotic reactions
for PLA degradation in compost. 相似文献
976.
针对仪化热电厂将循环水用作冲灰水,导致浓缩倍率只有1.6,以及凝汽器铜管腐蚀结垢严重等问题,提出了隔断循环水与冲灰水的直接联系,实现闲路循环,对凝汽器铜管进行酸洗,并对循环水实施加缓蚀阻垢荆、杀菌剂和旁流过滤等办法,全部实施后产生了很好的效益,值得借鉴。 相似文献
977.
978.
《环境质量管理》2018,27(4):125-133
Environmental management systems (EMS) have been introduced globally to reduce environmental degradation issues brought about by industrial development. The research discussed in this paper is aimed at identifying the benefits and motivations of the implementation of EMS in compliance with the International Organization for Standardization (ISO) 14001 standard in Malaysian industries by using the pairwise comparison method. Experts in EMS from the Scientific and Industrial Research Institute of Malaysia were invited to participate in the research panel. Based on the experts’ input, data analysis was carried out by using multi‐criteria pairwise comparisons. The findings showed the ranked benefits and motivations of the implementation of the ISO 14001 standard for businesses. The results can indicate to policy‐makers and business advisors how businesses can be encouraged to implement the ISO 14001. 相似文献
979.
珠江三角洲蔬菜基地蔬菜中邻苯二甲酸酯的含量特征 总被引:2,自引:0,他引:2
邻苯二甲酸酯是一类重要的环境激素类污染物。本文以气相色谱/质谱(GC/MS)联用检测技术,对珠江三角洲地区典型蔬菜生产基地蔬菜中6种邻苯二甲酸酯化合物进行测试分析。结果发现:(1)珠江三角洲地区典型蔬菜生产基地的蔬菜样品中,多数样品检测出6种邻苯二甲酸酯,总含量为0.46~12.02mg/kg。(2)基地蔬菜中单个邻苯二甲酸酯化合物的种类和含量因蔬菜种类、品种、部位和生长环境等因素而异。(3)同种类蔬菜在不同基地或同一基地不同种类蔬菜中邻苯二甲酸酯的含量分布不同。(4)大部分蔬菜中以邻苯二甲酸正二丁酯(DnBP)和邻苯二甲酸双(2-乙基己基)酯(DEHP)为主。 相似文献
980.
对辉县市城区2006—2011年间环境空气质量监测数据进行了评价,并对城区污染物浓度时空变化进行了分析。结果表明,辉县市城区大气污染主要表现为可吸入颗粒物污染严重,主要是能源结构不合理、锅炉废气污染严重、城区道路保洁方式落后等原因造成的,由此提出了合理规划城市布局、减少结构性污染等对策。 相似文献