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51.
Improving eco-efficiency is propitious for saving resources and reducing emissions, and has become a popular route to sustainable development. We define two energy-related eco-efficiencies: energy efficiency (ENE) and greenhouse gas (GHG) emission-related eco-efficiency (GEE) using energy consumption and the associated GHG emissions as the environmental impacts. Using statistical data, we analyze China??s energy consumption and GHG emissions by industrial subsystem and sector, and estimate the ENE and GEE values for China in 2007 as 4.871×107 US$/PJ and 4.26×108 US$/TgCO2eq, respectively. Industry is the primary contributing subsystem of China??s economy, contributing 45.2% to the total economic production, using 79.6% of the energy consumed, and generating 91.4% of the total GHG emissions. We distinguish the individual contributions of the 39 industrial sectors to the national economy, overall energy consumption, and GHG emissions, and estimate their energyrelated eco-efficiencies. The results show that although ferrous metal production contributes only 3.5% to the national industrial economy, it consumes the most industrial energy (20% of total), contributes 16% to the total industrial global warming potential (GWP), and ranks third in GHG emissions. The power and heat sector ranks first in GHG emissions and contributes one-third of the total industrial GWP, although it only consumes about 8% of total industrial energy and, like ferrous metal production, contributes 3.5% to the national economy. The ENE of the ferrous metal and power and heat sectors are only 8 and 2.1×107 US$/PJ, while the GEE for these two sectors are 9 and 4×104 US$/GgCO2eq, respectively; these are nearly the lowest ENE and GEE values among all 39 industry sectors. Finally, we discuss the possibility of ecoefficiency improvement through a comparison with other countries.  相似文献   
52.
In this study, greatly enhanced Mn(II) adsorption was achieved by as-synthesized diethylenetriaminepentaacetate acid intercalated Mg/Al layered double hydroxides(LDHsDTPA). The adsorption capacity of LDHs-DTPA was 83.5 mg/g, which is much higher than that of LDHs-EDTA(44.4 mg/g), LDHs-Oxalate(21.6 mg/g) and LDHs(28.8 mg/g). The adsorption data of aqueous Mn(II) using LDHs-DTPA could be well described by the pseudosecond order kinetics and Langmuir isotherm model. Thermodynamics study results also showed that the adsorption process of Mn(II) by LDHs-DTPA was exothermic as indicated by the negative ΔH value. Furthermore, based on the structural, morphological and thermostable features, as well as FT-IR and XPS characterizations of LDHs-DTPA and the pristine LDHs, the adsorption mechanism of Mn(II) was proposed. The carboxyl groups of DTPA were proposed to be the main binding sites for Mn(II), and the hydroxyl groups of LDHs also played a minor role in the adsorption process. Among the three common regeneration reagents, 0.1 mol/L Na_2CO_3 was the best for reusing LDHs-DTPA in Mn(II)adsorption. Besides, the Mn(II) adsorption performance could be hindered in the presence of typical inorganic ions, especially cations. Further specific modifications of LDHs-DTPA are suggested to get more selective adsorption of Mn(II) in practical applications.  相似文献   
53.
The composition, distribution and infestation sequence of organisms that destroy the commercially valuable shells of the black oyster Pinctada margaritifera var. cumingii Jameson, 1901 were studied. Three ecologically different groups of boring (euendolithic) organisms were identified: (1) phototrophic boring microorganisms (cyanobacteria, Hyella caespitosa, Hyella sp., Mastigocoleus testarum, Plectonema terebrans, and green algae, Phaeophila dendroides, Ostreobium quekettii); (2) heterotrophic boring microorganisms (fungi, Ostracoblabe implexa); (3) filter-feeding boring organisms (sponges, Cliona margaritiferae, C. vastifica). The phototrophic endoliths dominate the external pristmatic region of the shell, whereas the valuable interior nacreous region is attacked mainly by heterotrophs. Boring patterns reflect in part the shape and behaviour of the organisms and in part the structural properties of the shell, and inflict different types of damage. Infestation starts with microbial borers, which prepare the conditions for later invasion by more damaging clionid sponges. The infestation begins always at the apex, the oldest part of the shells, from which the periostracum is often removed by natural attrition or by cleaning procedure. The rate of bioerosion in 1 yr-old hatchery shells is 36 times higher than in natural populations.  相似文献   
54.
主要对紫木凼金矿区CN- 、As、Hg、Pb、Zn五个污染项目进行了趋势分析和污染预测。氰化物虽然是剧毒污染物 ,但它具有很强的自净降解作用 ,对矿区的污染影响不大 ,只是对于废液池的清洗外排必须先治理后排放。建立了As、Hg、Pb、Zn在各个污染途径中的定量分配模式。该模式表明 ,开采过程中As、Hg、Pb的大部分 ( 64 %以上 )进入废液池外排 ,其余的进入矿渣。在此基础上 ,对这些元素从 1 989年到 2 0 0 0年的开采总量、进入废液、土壤、积水坑的分量进行了计算 ,并给出了在堆场下伏粘土中各元素的饱和吸附量和开始外排的时间。  相似文献   
55.
毛显强  杨岚 《环境保护》2006,(1B):90-95
文章回顾了瑞典的环境税费,特别是与能源相关的环境税的发展沿革,从环境效益、财政效益、能源结构调整效应三个方面分析了瑞典能源一环境税的效果,并展望瑞典环境税的发展前景。最后指出了瑞典环境税制度对中国的借鉴意义。  相似文献   
56.
<正>现状"民以食为天",食品安全自然关乎人的生存质量。然而,近几年曝光的食品安全事件却有让人"应接不暇"之势,如三聚氰胺奶粉事件、苏丹红事件、大头婴儿奶粉事件、海南豇豆含毒事件等。频繁的食品安全事件不但使国人失去了对食品行业的  相似文献   
57.
宋文华  刘茂 《上海环境科学》1999,18(3):115-116,120
采用预先危险性分析和事故树分析剖地塞米松生产过程中毒物质产生中毒事故的危险性。指出溴甲烷和氟化氢是典型毒物。同时,利用泄漏和扩散模型定量分析它们泄漏所造成的危险性。结果表明:溴甲烷泄漏时,地面轴线浓度可以达到92.3mg/m^3,远大于其急性中毒阈值,并制定了相应的预防性工程措施。  相似文献   
58.
可生物降解材料聚羟基脂肪酸酯(PHA)的合成与应用概述   总被引:3,自引:0,他引:3  
聚羟基脂肪酸酯(polyhydroxyalkanoates,PHA)是很多微生物合成的一种细胞内聚酯,是一种天然的高分子生物材料。PHA具有良好的生物相容性能、生物可降解性和塑料的热加工等性能。文章主要综述了PHA的合成途径与有关应用方面的研究。  相似文献   
59.
文章回顾了瑞典的环境税费,特别是与能源相关的环境税的发展沿革,从环境效益、财政效益、能源结构调整效应三个方面分析了瑞典能源-环境税的效果,并展望瑞典环境税的发展前景.最后指出了瑞典环境税制度对中国的借鉴意义.  相似文献   
60.
面向回收的产品设计能够使废旧产品得到更好的回收和重用,优化拆卸序列的生成必须基于产品拆卸的经济性分析。论述了面向经济回收的产品设计系统的构成及相关的关键问题,分析了产品的零件材料回收价值与拆卸工艺,建立了零件材料合理回收的评估方法。  相似文献   
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