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461.
The aim of this paper is to study the spatialtemporal differentiation of industrial eco-efficiency in China. Using methods based on the data envelopment analysis (DEA) model and exploratory spatial data analysis (ESDA) and data from 1985, 1995, 2005, and 2008 of 30 provinces in China, the spatial-temporal pattern changes in industrial eco-efficiency are discussed. The results show that: first, the patterns of industrial eco-efficiency are dominated by clustering of relatively low efficiency provinces; second, spatial relationships between the industrial eco-efficiencies of different provinces changed slightly throughout the period and the provinces persistently exhibit spatial concentration of relatively low industrial eco-efficiency; finally, there is an obvious trend in the polarization of industrial eco-efficiency, i.e., the higher level spatial units are concentrated in eastern China, and the lower level spatial units are mainly in western and central China.  相似文献   
462.
Tetrahydrofuran (THF) is easy to volatilize and hard to biodegrade. Little is known about the influence and fate of tetrahydrofuran in the environment. The effects of THF were examined on dissolved oxygen, pH, culturable aerobic microbes (bacteria, actinomycetes, and fungi) and four selected enzymes (protease, phosphatase, amylase, and lipase) in wastewater. The wastewater containing some activated sludge was taken from the aeration basin in Sibao sewage plant in Hangzhou, China. THF at lower concentrations of enhanced aerobic respiration and higher concentrations decreased utilization of oxygen in wastewater. The short-term influence of THF on pH was not obvious, but the long-term effect was apparent. Inhibition of THF on culturable aerobic microbes rose with increasing THF concentrations but decreased with prolongation of incubation time. No effect of THF on the activity of protease, phosphatase, amylase, and lipase was found. Data indicate that lower concentrations of THF exert no marked influence on wastewater in an urban sewage plant.  相似文献   
463.
The construction of heterojunction photocatalysts for efficiently utilizing solar energy has attracted considerable attention to solve the energy crisis and reduce environmental pollution. In this study, we use the energy released from an easily-occurred exothermic chemical reaction to serve as the drive force to trigger the formation of Cd S and C3N4 nanocomposites which are successfully fabricated with cadmium nitrate and thiourea without addition of any solvents and prot...  相似文献   
464.
大亚湾的海     
吕军 《环境》2006,(4):54-54
看海,是我童年的一个梦想。三年前的一天,这个梦想成了现实。  相似文献   
465.
Cytochrome P450 (CYP450) genes play an important role in catalyzing oxidative metabolism of toxicants. Recently, CYP1 subfamily were discovered and reported in fish, however, little is known regarding the CYP2 isoforms in fish. In the present study, the cDNA fragments of CYP 1B1 and 1C1 and CYP2Aa, 2Y3, and 2K of rare minnow were cloned and exhibited a high amino acid sequence identity compared with their zebrafish orthologs. Basal expression showed CYP1C1 and CYP 2Aa expression were observed in all eight tissues analyzed (liver, gill, intestine, kidney, spleen, brain, skin, and muscle). CYP 1A, and 1B1 expression was found in all tissues except for muscle and skin. However, CYP 2Y3 was expressed in liver, spleen, intestine and muscle whereas CYP 2 K in liver, kidney and intestine. 4 and 100 μg L−1 Benzo[a]pyrene (BaP) induced patterns showed that CYP 1A, 1B1 and 1C1 expression in liver, gill, and intestine was strongly up-regulated (p < 0.05). Furthermore, CYP 2Y3 was strongly induced in liver from BaP treatments (p < 0.05). The high induction on mRNA level of CYP1s and CYP 2Y3 by BaP could be associated with catalyzing detoxification and indicated that CYP2s may also be potential biomarker to screen AHR agonist. The high responsiveness of CYP1 and 2 genes suggested Chinese rare minnow is feasible to screen and assess pollution with AHR agonist.  相似文献   
466.
A newly designed electric assisted micro-electrolysis filter(E-ME) was developed to investigate its degradation efficiency for coking wastewater and correlated characteristics. The performance of the E-ME system was compared with separate electrolysis(SE) and micro-electrolysis(ME) systems. The results showed a prominent synergistic effect on COD removal in E-ME systems. Gas chromatography/mass spectrometry(GC–MS) analysis confirmed that the applied electric field enhanced the degradation of phenolic compounds.Meanwhile, more biodegradable oxygen-bearing compounds were detected. SEM images of granular activated carbon(GAC) showed that inactivation and blocking were inhibited during the E-ME process. The effects of applied voltage and initial p H in E-ME systems were also studied. The best voltage value was 1 V, but synergistic effects existed even with lower applied voltage. E-ME systems exhibited some p H buffering capacity and attained the best efficiency in neutral media, which means that there is no need to adjust p H prior to or during the treatment process. Therefore, E-ME systems were confirmed as a promising technology for treatment of coking wastewater and other refractory wastewater.  相似文献   
467.
酸性甲醛改性对花生壳吸附重金属离子的影响   总被引:2,自引:0,他引:2  
花生壳的酸性甲醛改性对重金属离子的吸附有较大影响.改性过程使花生壳中一些含有羟基、羧基、芳香环、C-O和C-O-C键的混合物被脱除.改性后花生壳的等电点略有升高,而和羧基有关的表面负电荷量则明显降低.混合物的脱除使Pb2 的吸附量明显降低,Cr3 、Cu2 的吸附量改变不大.改性使羧基减少的同时也暴露了新的Cr3 、Cu2 的吸附位点.改性还有利于增加重金属离子在花生壳内孔中的传质速率,从而使吸附达到平衡的时间略有减少.  相似文献   
468.
灌河口附近海域水质状况调查研究   总被引:2,自引:0,他引:2  
近海水域的水环境对沿海城市的可持续发展具有重要意义.根据2006年4、5月灌河口附近海域水质监测资料,对海域的水质状况进行了分析和评价研究.结果表明:pH符合《海水水质标准》(GB3097-1997)Ⅰ类水质标准,DO、COD符合Ⅰ、Ⅱ类水质标准;油类含量的平均值在0.031~0.062mg/L间变化,水质符合Ⅰ、Ⅱ类水质标准;油类含量符合Ⅰ、Ⅱ类水质标准;无机氮和活性磷酸盐含量已经超过Ⅲ、Ⅳ类水质标准;灌河口附近特殊的潮流场及苏北沿岸流对污染物质的空间分布格局的影响较大,建议对该海域进行大规模的水文监测分析,加强对海域环境的科学管理,以便及时采取对策.  相似文献   
469.
唐山市发展循环经济的思考   总被引:2,自引:0,他引:2  
文章从树立和落实全面、协调、可持续的科学发展观的高度出发,结合唐山市产业结构、资源现状、环境保护以及发展循环经济的政策思路,阐述了发展循环经济的必要性、可行性,并从1.政府层面抓好宏观建设,建立循环经济有力保障措施;2.企业层面抓好重点环节,建立循环经济技术支撑体系;3.公众层面加大宣传力度,建立循环经济发展良好氛围三个方面论述了发展循环经济的具体措施和办法.并指出,唐山市发展循环经济意义重大,不仅是转变经济增长方式的有效途径,也是真正实现可持续发展的现实选择.  相似文献   
470.
城市生活垃圾压缩站环境污染研究   总被引:6,自引:0,他引:6  
通过对垃圾压缩站内生活垃圾进行采样分析、压实试验和环境污染检测,得出了城市生活垃圾压实密度和施加压力的关系曲线,确定了对垃圾压实的合适压力范围为0.1~0.2MPa;垃圾压缩站环境污染严重,垃圾压缩污水量为10-50kg/t,其中BOD5和COD平均分别超标111倍和486倍;环境噪音只有50m以外才能达到居民区环境质量二级标准(60dB(A))的噪音要求;产生的臭气在较低风速下一般扩散25m时污染达到最大,NH3、H2S分别可以达到0.011、0.0046mg/m^3,这个值占容许浓度的55%和46%。  相似文献   
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