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911.
以非贵金属Cu、Fe、Mn和Ce为主要活性成分和TiO2、-γA l2O3为载体,制备了10种用于催化湿式氧化法处理糖蜜酒精废液的催化剂。考察了载体、焙烧温度、成分配比对催化剂催化活性与稳定性的影响,研究了氧气分压、催化剂投加量、反应温度和反应时间对催化湿式氧化过程的影响规律。结果表明:(1)Fe-Mn/-γA l2O3(3∶1∶1)催化剂是催化湿式氧化法处理糖蜜酒精废液的可选催化剂;(2)适宜的氧气供应量为理论需氧量的3.4~4.6倍,催化剂的投加量以10 g/L为佳;在300℃下反应30 m in或在280℃下反应60 m in,处理水可达到污水综合排放标准GB9878-1996的三级标准。  相似文献   
912.
降酚菌株的固定化细胞处理含酚废水的性能研究   总被引:2,自引:0,他引:2  
用海藻酸钠作为载体将一株降酚菌株进行固定化包埋。利用正交实验确定了该菌株固定化细胞制备的最优条件。研究表明,该降酚菌株的固定化细胞对苯酚的降解能力和耐受能力均大于游离细胞。降酚菌株固定化细胞降解苯酚的最适温度范围是30~35℃,最适pH值范围为6~8。该菌株的固定化细胞对废水中的COD也具有良好的降解效果。  相似文献   
913.
铁屑吸附-微波辐照-内电解协同处理结晶紫染料废水   总被引:8,自引:0,他引:8  
以结晶紫为模型化合物,提出了一种新的“铁屑吸附—微波辐照—内电解”协同处理染料废水的方法。试验结果表明,吸附在铁屑表面的染料通过微波催化裂解和内电解协同作用迅速降解,染料溶液的脱色率和COD去除率分别达到99%和95%以上。废铁屑经8次使用后仍有良好的处理效果。研究了各种相关因素对染料废水脱色的影响。  相似文献   
914.
本文采用TG-FTIR分析方法深入研究了火场中硬木地板材料和棉花秆变氧浓度燃烧过程,深入分析了氧浓度对纤维物质燃烧表观热失重影响;通过大量的动力学参数计算得出了可燃物的表观活化能与实际氧浓度成线性关系;分析了氧浓度对木材燃烧气体产物的影响,并探索了氧浓度影响热解和燃烧的机理。  相似文献   
915.
In landfill, high temperature levels come from aerobic reactions inside the waste surface layer. They are known to make anaerobic processes more reliable, by partial removal of easily biodegradable substrates. Aerobic biodegradation of the main components of biodegradable matter (paper and cardboard waste, food and yard waste) is considered. In this paper, two models which take into account the effect of moisture on aerobic biodegradation kinetics are discussed. The first one (Model A) is a simple, first order, substrate-related model, which assumes that substrate hydrolysis is the limiting step of the process. The second one (Model B) is a biomass-dependant model, considering biological growth processes. Respirometric experiments were performed in order to evaluate the efficiency of each model. The biological oxygen demands of shredded paper and cardboard samples and of food and yard waste samples prepared at various initial water contents were measured. These experimental data were used to identify model parameters. Model A, which includes moisture dependency on the maximum amount of biodegraded matter, is relevant for paper and cardboard biodegradation. On the other hand, Model B, including moisture effect on the growth rate of biomass is suitable to describe food and yard waste biodegradation.  相似文献   
916.
Adsorption-desorption characteristics of mercury in paddy soils of China   总被引:1,自引:0,他引:1  
Mercury (Hg) has received considerable attention because of its association with various human health problems. Adsorption-desorption behavior of Hg at contaminated levels in two paddy soils was investigated. The two representative soils for rice production in China, locally referred to as a yellowish red soil (YRS) and silty loam soil (SLS) and classified as Gleyi-Stagnic Anthrosols in FAO/UNESCO nomenclature, were respectively collected from Jiaxin County and Xiasha District of Hangzhou City, Zhejiang Province. The YRS adsorbed more Hg(2+) than the SLS. The characteristics of Hg adsorption could be described by the simple Langmuir adsorption equation (r2 = 0.999 and 0.999, P < 0.01, respectively, for the SLS and YRS). The maximum adsorption values (Xm) that were obtained from the simple Langmuir model were 111 and 213 mg Hg(2+) kg(-1) soil, respectively, for the SLS and YRS. Adsorption of Hg(2+) decreased soil pH by 0.75 unit for the SLS soil and 0.91 unit for the YRS soil at the highest loading. The distribution coefficient (kd) of Hg in the soil decreased exponentially with increasing Hg(2+) loading. After five successive desorptions with 0.01 mol L(-1) KCl solution (pH 5.4), 0 to 24.4% of the total adsorbed Hg(2+) in the SLS soil was desorbed and the corresponding value of the YRS soil was 0 to 14.4%, indicating that the SLS soil had a lower affinity for Hg(2+) than the YRS soil at the same Hg(2+) loading. Different mechanisms are likely involved in Hg(2+) adsorption-desorption at different levels of Hg(2+) loading and between the two soils.  相似文献   
917.
建设绿色企业文化是秦皇岛港实现绿色发展的前提,对港口的发展有深远的意义和重要作用.秦皇岛港应从强化领导意识、提高职工素质、完善绿色制度体系、构建绿色企业形象等方面入手建设港口绿色企业文化.  相似文献   
918.
图书馆藏书大多存在实物与财产登记不符的状况,如情况较为严重则会影响到图书馆流通、采访等项工作的开展,因此适时进行书库清点具有重要意义。本文以中国环境管理干部学院图书馆的清点为实例,初步探讨了将条码作为清点切入点的书库清点工作的方法、步骤和注意事项。  相似文献   
919.
Water level response to hydropower development in the upper Mekong River   总被引:3,自引:0,他引:3  
Li S  He D 《Ambio》2008,37(3):170-177
Environmental changes and their transboundary influences on the Mekong watercourse system have been an international research focus in recent years, but the opinions and results related to the impacts of upper Mekong River dams are quite different. In this paper, based on the records of water levels from 1960 to 2003 at three mainstream sites in the upper Mekong River, a quantitative examination has been undertaken into characteristics of the mainstream water-level process at multiple timescales and its response to cascade development. The major results are: i) Annual mean, wet period mean, and the mean water levels during the period between March and April (PBMA period) exhibit a significant increasing trend at Jiuzhou and Yunjinghong sites, which are influenced by large-scale factors such as climate change and solar activity. ii) The interdecadal and interannual variations of annual mean, annual maximum, and wet period mean water levels at three sites show similar features during the dam construction period. iii) The interdecadal variations of PBMA period water level show a gradual increase at Gajiu and Yunjinghong sites but a falling trend at Jiuzhou; these trends confirm that there is some regulation on the flow in the dry season caused by the two existing dams. iv) The downstream effects of the present dams on water levels are very limited at the annual mean and wet season mean levels, not apparent at the monthly and yearly timescales, and relatively significant at daily and hourly timescales.  相似文献   
920.
Anaerobic degradation behavior of nonylphenol polyethoxylates in sludge   总被引:1,自引:0,他引:1  
Lu J  Jin Q  He Y  Wu J  Zhang W  Zhao J 《Chemosphere》2008,71(2):345-351
Anaerobic biodegradation behavior of nonylphenol polyethoxylates (NPEOs) was investigated. Results showed that terminal electron acceptors, organic matters, initial concentration, and temperature had great influence on the anaerobic biodegradation of NPEOs. Anaerobic biodegradation of NPEOs could be enhanced by adding sulfate or nitrate while this process could be inhibited by adding organic matters. The maximum removal rate increased 1.24 microM d(-1) for each ten micromoles increase in initial concentration. The decrease in temperature caused a sharp decrease in the removal efficiency of NPEOs. The temperature coefficient (PHI) for the anaerobic biodegradation of NPEOs was 0.01 degrees C(-1). Nonylphenol (NP), the typical intermediate of NPEOs, could inhibit the anaerobic biodegradation of NPEOs only at high concentration. However, these environmental factors had no effect on the anaerobic biodegradation pathway of NPEOs. The accumulation of NP and short-chain NPEOs during NPEO biodegradation led to a significant increase in the estrogenic activity during the biodegradation period.  相似文献   
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