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731.
732.
欧阳培 《再生资源与循环经济》2011,4(6)
湖南在加快转变经济发展方式的进程中,从"一化三基"到"四化两型"的战略升级,更加注重培育以低碳排放为特征的新的经济增长点,把环保作为转变发展方式的"闸门"和"调节阀",着力推进自主创新,培育战略性新兴产业,建设低碳城市,全面推进湘江流域环境综合整治,打造湘潭九华示范区"两型"产业平台,多措并举发展低碳经济,在新的更高起点上推动湖南又好又快发展. 相似文献
733.
Jinyang Chen Zhi Li Lujiang Jin Pei Ni Guiyang Liu Haibo He Jianqiu Zhang Junping Dong Ruyi Ruan 《Journal of Material Cycles and Waste Management》2010,12(4):321-325
Depolymerization of nylon 6 to produce ε-caprolactam using an environmentally friendly heteropoly acid catalyst was studied
at temperatures between 553 and 603 K in water. The products of depolymerization were analyzed qualitatively and quantitatively
by means of mass spectrometry and high-performance liquid chromatography. The results showed that the depolymerized product
was mainly ε-caprolactam with a little 6-aminocaproic acid and oligomers. The phosphotungstic heteropoly acid used as a catalyst
can improve the hydrolysis rate and yield of ε-caprolactam. The optimum hydrolysis conditions for ε-caprolactam yield were
as follows: phosphotungstic heteropoly acid content, 3%; reaction temperature, 573 K; and reaction time, 85 min. Under these
conditions, the yield of ε-caprolactam was 77.96%. In the temperature range 553–603 K, the activation energy of 3% phosphotungstic
heteropoly acid-catalyzed depolymerization was evaluated as 77.38 kJ/mol, which is lower than the 86.64 kJ/mol value for no
catalyst. 相似文献
734.
Hongli Xu Yuan Li Pei Zhu Xishi Wang Heping Zhang 《Journal of Loss Prevention in the Process Industries》2013,26(4):815-820
In this paper, experimental investigations were performed for the mitigation via an ultra-fine water mist of methane/coal dust mixture explosions in the presence of obstacles to reveal the effects of the obstacles in this scenario. Two PCB piezo-electronic pressure transducers were used to acquire the pressure history, a Fastcam Ultima APX high-speed video camera was used to visualize both the process of the mixture explosion and its mitigation. The diameters of the coal dust, the types of obstacles and the volumes of ultra-fine water mist were varied in the tests. The parameters of the explosion overpressure and the range of critical volume flux of the ultra-fine water mist for explosion mitigation were determined. The results show that the mixture explosion and its mitigation are primarily influenced by the number, shape and set locations of the obstacles. When the volume flux of the water mist is larger than a certain amount, the mixture explosions and the effects of obstacles can be completely mitigated with the ultra-fine water mist. 相似文献
735.
以吉富罗非鱼(Oreochromis niloticus)作为研究对象,采用室内水族箱模拟水生态系统,研究了20 d试验期内,水体中初始质量浓度为0.05 g L-1的三聚氰胺在罗非鱼肝脏中的累积规律及不同暴露时间,对罗非鱼肝脏中7-乙氧基-异酚噁唑酮-脱乙基酶(EROD)和谷胱甘肽-S-转移酶(GST)活性的影响。结果表明:随着试验时间的延长,三聚氰胺在罗非鱼肝脏中的质量分数先迅速上升,在第2天高达4.15 mg·kg-1。随后逐渐下降,在第20天降至0.8 mg·kg-1,恢复到暴露初期水平。与对照组相比,罗非鱼肝脏中EROD和GST的活性在第1天被轻微诱导之后,分别在第2天和第4天开始被显著抑制,抑制率分别为50.7%和69.4%。随后两者的活性上升并分别在第7天和第10天开始被显著诱导,诱导率各为122.9%和47.7%。总体上看,EROD和GST的活性皆呈现出诱导-抑制-诱导的变化趋势。但在暴露结束时,这两种酶的活性又显著低于对照组,抑制率分别为34.1%和20.3%。结果显示,罗非鱼肝脏中EROD酶和GST酶,在一定程度上可作为水体中三聚氰胺污染的生物监测指标。 相似文献
736.
737.
Feng-Tang Chang Yu-Chih Lin Bau-Shei Pei 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1384-1390
Abstract The use of a honeycomb zeolite concentrator and an oxidation process is one of the most popular methods demonstrated to control volatile organic compound (VOCs) emissions from waste gases in semiconductor manufacturing plants. This study attempts to characterize the performance of a concentrator in terms of the removal efficiencies of semiconductor VOCs (isopropyl alcohol [IPA], acetone, propylene glycol methyl ether [PGME], and propylene glycol monomethyl ether acetate [PGMEA]) under several parameters that govern the actual operations. Experimental results indicated that at inlet temperatures of under 40 °C and a relative humidity of under 80%, the removal efficiency of a zeolite concentrator can be maintained well over 90%. The optimal rotation speed of the concentrator is between 3 and 4.5 rph in this study. The optimal rotation speed increases with the VOCs inlet concentration. Furthermore, reducing the concentration ratio helps to increase the removal efficiency, but it also increases the incineration cost. With reference to competitive adsorption, PGMEA and PGME are more easily adsorbed on a zeolite concentrator than are IPA and acetone because of their high boiling points and molecular weights. 相似文献
738.
739.
详细介绍了 1996年 11月 9日南黄海 6 1级地震前 ,巢湖地下水动态观测网中 3口水井所记录到的水位经标准差、剩余值数据处理得到的前兆异常。其异常时间以中短期为主 ,不同步。此外还对降雨对井水位的影响以及如何提高地震预报的准确性等问题进行了讨论。 相似文献
740.
采用等体积浸渍法制备了MnOx/CNTs催化剂,用于低温NH3选择性催化还原(SCR)NO的实验。使用BET,FT-IR,TEM和XRD对催化剂进行表征,结果表明:碳纳米管经混酸超声分散,增加了羧基活性基团,锰氧化物颗粒分布较均匀。在模拟烟气条件下,考察了催化剂的MnOx负载量、煅烧温度及质量和烟气流速比(W/F)对NO脱除率的影响。煅烧温度为773 K,MnOx负载量为10%时,NO脱除率达到98.56%;W/F为2-3 mg/(mL·min^-1)时NO的脱除率更高。 相似文献