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北京大气重污染过程PM_(10)中水溶性盐的研究 被引量:27
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作者 张凯 王跃思 +3 位作者 温天雪 胡波 刘广仁 Meslmani Yousef 《中国环境科学》 EI CAS CSCD 北大核心 2006年第4期385-389,共5页
利用大气颗粒物快速捕集及化学成分在线分析系统,观测了2004年秋季北京出现的一次长时间严重污染天气过程中PM10的水溶性无机盐浓度的变化.结果表明,PM10中总水溶性无机盐浓度在这次重污染过程中升高了4.7倍.硝酸盐、硫酸盐、铵盐的浓... 利用大气颗粒物快速捕集及化学成分在线分析系统,观测了2004年秋季北京出现的一次长时间严重污染天气过程中PM10的水溶性无机盐浓度的变化.结果表明,PM10中总水溶性无机盐浓度在这次重污染过程中升高了4.7倍.硝酸盐、硫酸盐、铵盐的浓度分别升高7.9,4.1,5.4倍,这3种无机盐的日变化在污染期和非污染期有明显差异.污染期SO2、NOx向SO42-、NO3-转化率明显高于非污染期. 展开更多
关键词 重污染 PM10 硝酸盐 硫酸盐 铵盐
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ADSORPTION OF 2,4-DICHLOROPHENOL IN AQUEOUS SOLUTION ONTO ADSORPTION RESIN MODIFIED BY N-ACETYLANILINE 被引量:7
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作者 费正皓 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第3期263-269,共7页
A hypercrosslinked adsorption resin (ZH-05) modified by N-acetylaniline in the post crosslinking process was prepared. The adsorption properties of ZH-05 toward 2,4-dichlorophenol in comparison with granular activat... A hypercrosslinked adsorption resin (ZH-05) modified by N-acetylaniline in the post crosslinking process was prepared. The adsorption properties of ZH-05 toward 2,4-dichlorophenol in comparison with granular activated carbon (GAC) and Amberlite XAD-4 were observed. The present study mainly focuses on the static equilibrium adsorption behaviors, desorption profiles and the proof of chemisorption. The results show that the Langmuir equation can give a perfect fitting to experimental data, and high temperature was favorable for adsorption of 2,4-dichlorophenol on ZH-05. A related equation was used to correlate the amount of chemisorption and the suppositionai chemisorption equilibrium concentration of adsorbate in aqueous solution. The adsorption capacities from different ranges of temperature and the static desorption experiment both reveal the same conclusion, i.e., the adsorption of 2,4-dichlorophenol from water on ZH-05 is a coexistent process of physical adsorption and chemical transition as on GAC. 展开更多
关键词 Adsorption resin 2 4-DICHLOROPHENOL CHEMISORPTION Chemical modification
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Pyrite Formation in Organic-rich Clay, Calcitic and Coal-Forming Environments 被引量:4
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作者 Gordana DEVI Petar PFENDT +1 位作者 Branimir JOVANIEVI Zoran POPOVIC 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期574-588,共15页
The early diagenetic characteristics of pyrite formation processes in a Miocene freshwater sequence of mixed sediments (coal fragments in clays, sandstones or shales) alternating with continuous brown coal layers wa... The early diagenetic characteristics of pyrite formation processes in a Miocene freshwater sequence of mixed sediments (coal fragments in clays, sandstones or shales) alternating with continuous brown coal layers was investigated. Based on abundant minerals, the following main sedimentary environments were distinguished: the illite-montmorillonitic (I-M), calcitic (Ct) and coal-forming environment (CL). For these hydrogeochemically differing environments the effects of limiting factors on the pyrite formation process (availability of sulphate and Fe, amount of organic matter and participation of organic sulphur) were assessed by correlation analysis. Significant differences in the effects of these limiting factors in the particular environments were observed. These differences were explained taking in account the different oxidative activity, Fe-complex and surface complex forming properties of humic substances in dependence of pH of environment and the abundance of sorptionally active clay minerals. In environments having a relatively low pH and containing clay minerals (I-M- and CL-environments) the oxidative activity of humic substances (Hs) on pyrite precursors was greatly prevented however pyrite formation depended on reactive Fe availability as the consequence of complex formation. On the contrary, in environments with a relatively high pH, as it was the calcitic, the oxidative activity of Hs was greatly enhanced, thus oxidizing the sulfur precursors of pyrite. The oxidation degree of organic matter was probably also a consequence of the differing activity of the humic electron-acceptors. 展开更多
关键词 early diagenesis pyrite formation humic electron-acceptors calcitic environment illitemontmorillonitic environment COAL mixed sediments
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Comprehensive Analysis of 9-year Running Data of A^2/O-MBR in Xi an Siyuan University 被引量:6
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作者 Xuemei ZHANG Jingyuan HAO +3 位作者 Qinghua MA Dong LI Bo FU Baolan QIN 《Meteorological and Environmental Research》 CAS 2020年第5期139-143,共5页
Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has be... Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has been treated,and 4.405 million m^3 of water reaching the national urban miscellaneous water standard has been reclaimed and reused.A total of 25 km pipeline,5 pits,scenery fountains,lakes,and 12 pump stations have been constructed for flushing toilets,irrigating green grass lawn and afforest,and cleaning hardened pavement.The design and construction of 5 pits,scenery fountains,and lakes are important to meet the national urban miscellaneous water standard under occasional phosphorus and/or nitrogen exceed concentration.The unit water cost is 4.19 yuan/m^3,including membrane modules depreciation and amortization.After the A 2/O-MBR system passes the membrane modules depreciation and amortization period,the unit water cost is 2.82 yuan/m^3.The water productivity of the membrane stack rises first at the beginning of operation,reaches the maximum value,and then decreases.The average annual transmembrane pressure difference increases by 1.12 kPa.The average VMD of industrial permeability decreases annually by 0.45 m^3. 展开更多
关键词 Wastewater treatment and reuse system A 2/O-MBR system Economic feasibility Industrial permeability Membrane fouling
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Effects of ketogenic diet and ketone bodies on the cardiovascular system:Concentration matters 被引量:4
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作者 Souad Nasser Varvara Vialichka +2 位作者 Marta Biesiekierska Aneta Balcerczyk Luciano Pirola 《World Journal of Diabetes》 SCIE 2020年第12期584-595,共12页
Ketone bodies have emerged as central mediators of metabolic health,and multiple beneficial effects of a ketogenic diet,impacting metabolism,neuronal pathologies and,to a certain extent,tumorigenesis,have been reporte... Ketone bodies have emerged as central mediators of metabolic health,and multiple beneficial effects of a ketogenic diet,impacting metabolism,neuronal pathologies and,to a certain extent,tumorigenesis,have been reported both in animal models and clinical research.Ketone bodies,endogenously produced by the liver,act pleiotropically as metabolic intermediates,signaling molecules,and epigenetic modifiers.The endothelium and the vascular system are central regulators of the organism’s metabolic state and become dysfunctional in cardiovascular disease,atherosclerosis,and diabetic micro-and macrovascular complications.As physiological circulating ketone bodies can attain millimolar concentrations,the endothelium is the first-line cell lineage exposed to them.While in diabetic ketoacidosis high ketone body concentrations are detrimental to the vasculature,recent research revealed that ketone bodies in the low millimolar range may exert beneficial effects on endothelial cell(EC)functioning by modulating the EC inflammatory status,senescence,and metabolism.Here,we review the long-held evidence of detrimental cardiovascular effects of ketoacidosis as well as the more recent evidence for a positive impact of ketone bodies—at lower concentrations—on the ECs metabolism and vascular physiology and the subjacent cellular and molecular mechanisms.We also explore arising controversies in the field and discuss the importance of ketone body concentrations in relation to their effects.At low concentration,endogenously produced ketone bodies upon uptake of a ketogenic diet or supplemented ketone bodies(or their precursors)may prove beneficial to ameliorate endothelial function and,consequently,pathologies in which endothelial damage occurs. 展开更多
关键词 Endothelial cells Ketone bodies Vascular physiology β-Hydroxybutyrate β-Hydroxybutyrylation Histone post-translational modifications
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Experimental research on adsorption/desorption for petroleum pollutants in the soil in Daqing oilfield 被引量:1
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作者 Xiaoyan LIU Yingli LI +4 位作者 Guocheng MAO Jungang LI Chun LI Jingxin SUN Qianya ZHU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期260-260,共1页
关键词 大庆市 石油污染 土壤 吸附作用 污染化学
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Heavy Metals Contamination in Greenhouse Soils and Vegetables in Guanzhong, China 被引量:2
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作者 Ling Liu Jinyin Lu +3 位作者 Zhenwen Zhang Hai Zheng Xiaoqing Gao Wei Zhang 《Journal of Encapsulation and Adsorption Sciences》 2014年第3期80-88,共9页
This study used a flame atomic absorption spectrometer (FAAS) and atomic fluorescence spec-trophotometer (AFS) to detect the concentrations of chromium (Cr), cadmium (Cd), lead (Pb), hy-drargyrum (Hg) and arsenic (As)... This study used a flame atomic absorption spectrometer (FAAS) and atomic fluorescence spec-trophotometer (AFS) to detect the concentrations of chromium (Cr), cadmium (Cd), lead (Pb), hy-drargyrum (Hg) and arsenic (As) in soils and three genotypes of vegetables in greenhouse, as well as analyzed the physical and chemical properties of soils, including soil pH, soil organic matter (OM), basic nutrients, electrical conductivity (EC) and cation exchange capacity (CEC) in Guan- zhong areas, Shaanxi province, China. The results showed that comparing to subsoil, the sampled topsoil is enriched in Cr, Cd, Pb, As and Hg. Cd (0.83 - 3.17 mg·kg-1) and Hg (0.40 - 1.44 mg·kg-1) are exceeding the limited value stated in “the 2006 Greenhouse Vegetable Producing Environmental Quality Evaluation Standards” of 0.40 mg·kg-1 and 0.35 mg·kg-1 respectively. However, Nanzhuang greenhouse soil is within the limits. The heavy metal pollution index (HPI) of soil in Sanyuan (8.10) is the highest and in Dongzhang (4.23) is the lowest. The contents of Pb (0.201 - 0.376 mg·kg-1) were exceeding the limited value (0.20 mg·kg-1) in vegetables species, and Cd (0.0363 - 0.0572 mg·kg-1) in some place were also exceeding the limited value (0.05 mg·kg-1). Greenhouse soils were becoming acidified year after year;the ratios of N, P and K in soil were seriously imbalanced. According to the impacting factors, OM, pH, available P, EC and CEC have obviously effected the accumulation of Cr and Hg. However, there was not enough evidence for the effects of available nitrogen and available potassium. 展开更多
关键词 HEAVY Metals SOILS VEGETABLES GREENHOUSE
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Microstructure characterization and electrochemical corrosion behavior of Zn and Zn/Mg alloys in H_2SO_4 solution
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作者 S.H.Ettefagh Far A.Rahimi +1 位作者 M.Chaghazardi A.Davoodi 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2007-2013,共7页
The three systems of pure Zn, Zn-0.10% Mg(mass fraction), and Zn-0.15% Mg(mass fraction) were cast under controlled atmosphere and their microstructures were characterized by SEM/EDS analysis. The electrochemical corr... The three systems of pure Zn, Zn-0.10% Mg(mass fraction), and Zn-0.15% Mg(mass fraction) were cast under controlled atmosphere and their microstructures were characterized by SEM/EDS analysis. The electrochemical corrosion behavior of these three samples was examined in the very aggressive solution of 50% H2SO4(mass fraction) using electrochemical impedance spectroscopy(EIS) and potentiodynamic polarization measurements. The results show that magnesium improves in some extent the corrosion resistance of pure Zn in 50% H2SO4(mass fraction) confirmed by EIS test. Results of polarization measurment also demonstrate that small amount of Mg significantly improves the passivation of Zn in the test solution. Results of surface morphology of the samples and EDS analysis reveal that Mg reduced the corrosion attacks to pure Zn. 展开更多
关键词 电化学腐蚀行为 硫酸溶液 微观结构表征 锌合金 SEM/EDS分析 质量分数 电化学阻抗谱 可控气氛
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Advances on bioremediation of oil-contaminated soil in cold region
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作者 Xiaoyan LIU Jingxin SUN +4 位作者 Guocheng MAO Chunlei DAI Chun LI Qianya ZHU Yingli LI 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期96-97,共2页
关键词 寒冷地区 土壤污染 石油 生物降解作用
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Pollution Monitoring Methods and Results of Primorsky Kray Shoreline
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作者 Iana Blinovskaia 《Journal of Earth Science and Engineering》 2014年第10期605-611,共7页
关键词 岸边污染带 海岸线 监测方法 海洋垃圾 线结 海边 有机物质 环境影响
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Effect of distortion degree on the hydration of red mud base cementitious material
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作者 SUN Wen-biao FENG Xiang-peng ZHAO Guang-xing 《Journal of Coal Science & Engineering(China)》 2009年第1期88-93,共6页
The interaction of Si anions with AI sites during the hydration process was observed by NMR, IR and SEM to understand the reaction mechanism of the hydrates formation mixed with oil shale calcined at different tempera... The interaction of Si anions with AI sites during the hydration process was observed by NMR, IR and SEM to understand the reaction mechanism of the hydrates formation mixed with oil shale calcined at different temperatures. As the reaction progressed,the coordination of AI (IV, V, and VI) changed almost completely to IV, when mixed with oilshale calcined at 700^(。)C. However, when mixed with oil shale calcined at 400^(。)C, some6-coordination of AI still remained in the hydrates. Under the function of alkaline solutions,which were produced with the hydration of clinker, a certain amount of Si and AI atomsdissolved or hydrolyzed from aluminosilicate, formed geomonomers in solutions, and thenpolycondensed to form networks. 展开更多
关键词 水化过程 胶凝材料 影响程度 水合物形成 赤泥 失真 反应机理 油页岩
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Forest land use discontinuity and northern red oak Quercus rubra introduction change biomass allocation and life strategy of lingonberry Vaccinium vitis-idaea
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作者 Beata Woziwoda Marcin K.Dyderski Andrzej M.Jagodziński 《Forest Ecosystems》 SCIE CSCD 2021年第1期109-123,共15页
Background:Multi-purpose use of forests in a sustainable way forces a recognition of how introduction of alien woody species in forests with different land use histories affect native plants other than trees.Lingonber... Background:Multi-purpose use of forests in a sustainable way forces a recognition of how introduction of alien woody species in forests with different land use histories affect native plants other than trees.Lingonberry Vaccinium vitis-idaea is an important understory component of temperate and boreal forests and provider of valuable non-wood forest products.Here we studied effects of land use changes and introduction of Northern red oak Quercus rubra on lingonberry in mesic Scots pine forests(in central Poland).We measured lingonberry cover,height of shoots,biomass of stems and leaves,and fruit productivity.Shoots were collected within 200 research plots located in recent and ancient Scots pine forests,with and without Q.rubra.Results:We found that V.vitis-idaea reached lower cover,aboveground biomass and fruit production in recent than ancient forests and in forests with than without Q.rubra.The fruit production in recent pine forest was only 2%of that reported in ancient pine forest,and V.vitis-idaea did not reproduce generatively in forests with Q.rubra.Biomass and carbon sequestration of V.vitis-idaea in forests with alien(invasive)trees decreased by 75%compared to ancient pine forest.Effects were also clear at the individual shoot level–in less suitable conditions we found taller heights and higher biomass allocation into stems than foliage.Biomass allocation in fruiting and non-fruiting shoots in pine forests was also different–less of the dry biomass of fruiting shoots was allocated to leaves than to stems.Conclusions:In the age of high interest in ecosystem services and discussions about usage of alien tree species as alternatives in forest management,our results clearly indicate disruption of ecosystem services provided by V.vitisidaea in the presence of Q.rubra.Lingonberry benefited from the continuity of forest land use,however,regardless of land-use legacy,alien tree introduction led to decline in abundance of species crucial for ecosystem functioning.Therefore,to maintain valuable native species and for conservation of ecosystem services delivery,we suggest limiting the introduction of Q.rubra in areas with abundant V.vitis-idaea,especially in forests with continuous forest land-use history. 展开更多
关键词 Ancient and recent forest Understory biomass Ecosystem services Invasive tree Lingonberry Non wood forest products Red oak introduction Scots pine monoculture
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Analysis of the quick corrosion of blast furnaces’gas pipes after the installation of dry-type de-dusting equipment and discussion about measures
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作者 YANG Zhen YANG Qianyu +1 位作者 DENG Wanli QIAN Yuhai 《Baosteel Technical Research》 CAS 2011年第4期60-64,共5页
Compared with the traditional wet-type de-dusting technology ,the dry-type de-dusting technology is considered to be environmentally friendly and energy-saving. However, the pipes carrying the de-dusted blast fiLrnace... Compared with the traditional wet-type de-dusting technology ,the dry-type de-dusting technology is considered to be environmentally friendly and energy-saving. However, the pipes carrying the de-dusted blast fiLrnace gas (BFG) tends to be corrosive more quickly and seriously. In order to investigate the reasons for the quick corrosion, the gas pipes and auxiliary bellows installed in Baosteel' s newly built BFG dry-type de-dusting system are studied. The corrosive properties of the condensed water, such as the pH value, are measured and analyzed. Meanwhile, various factors that may influence the corrosion rate of the pipes are studied by experiment. On the basis of the investigation and research, the causes of corrosion and leakage on the pipes are discovered. It is the process of dry de-dusting that is responsible ,to a large extent, for the quick corrosion of the pipes. The equipment of spray tower is introduced and its effects are then discussed. This tower is designed to eliminate most of chloridion and neutralized the acid by spraying the alkaline water to the dedusted gas flow. The practical operation shows that the tower helps to lessen the corrosiveness of the dry de-dusted gas effectively. The last part of this study analyzes the possible impacts of the dry-type de-dusting process of the newly built blast furnace (BF) on the main BFG piping which has been in the state of being corroded for years by estimating its potential corrosion rate, and some suggestions on maintenance are given as well. 展开更多
关键词 blast furnace gas (BFG) dry-type de-dusting technology gas piping CORROSION
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Size Distribution of Particulate Matter of Metals in Urban Aerosols, Comarca Lagunera, Mexico
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作者 Roman Perez Sylvia Miranda +4 位作者 Alfredo Campos Jorge Carrillo Elias Ramirez Gonzalo Garcia Herrera 《Journal of Environmental Science and Engineering(A)》 2012年第11期1260-1266,共7页
关键词 含金属 气溶胶粒子 电感耦合等离子体原子发射光谱法 粒度分布 颗粒物 墨西哥 ICP-AES 城市
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Relationship between the microstructure and reaction performance of aluminosilicate
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作者 Xiao-ming Liu Heng-hu Sun +1 位作者 Xiang-peng Feng Na Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第1期108-115,共8页
A systematic study was conducted to comprehend the mechanism of thermal activation of silica-alumina materials by using ^29Si and ^27Al magnetic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy. The ... A systematic study was conducted to comprehend the mechanism of thermal activation of silica-alumina materials by using ^29Si and ^27Al magnetic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy. The reaction performance of silica-alumina-based materials with different molar ratios of Si/Al, which were thermally activated, was also investigated. With the increase in calcining temperature, the coordination of Al in metakaolin becomes four, five, and six firstly, and then transforms completely to four and six. It is indicated by identical coupled plasma optical emission spectroscopy (ICP) and NMR that, the reaction performance of monomeric silicate anions is better than that of polymeric silicate anions which are primarily cross-linked in the alkali solution. Moreover, it also shows that the thermal activation temperature, cooling method, and the molar ratio of Na/Ca have remarkable effects on the reaction performance. 展开更多
关键词 CALCINATION ALUMINOSILICATE reaction performance microstructure nuclear magnetic resonance
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Survey of Ecotourism Landscape Resources and Shrub Landscape Resources in Western Sichuan Mountains
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作者 YU Qiannan PENG Yong +4 位作者 LIU Zheng LI Ting HU Jun HUANG Tao LIU Qing 《Journal of Landscape Research》 2020年第5期26-33,共8页
As a high-end tourism activity advocating back to nature and protecting the nature,ecotourism has won increasing attention in recent years home and abroad.Being endowed with outstanding topographical and natural lands... As a high-end tourism activity advocating back to nature and protecting the nature,ecotourism has won increasing attention in recent years home and abroad.Being endowed with outstanding topographical and natural landscape resources,Sichuan has been a major ecotourism province in China.Particularly,western Sichuan mountains is more scarcely populated area with great topographical fluctuations,thus it is more suitable for developing ecotourism activities than eastern Sichuan.Based on previous researches and statistical analysis,this paper reviewed the overall situation of ecotourism landscape resources in western Sichuan mountains,including its geomorphological landforms,hydrographic landscapes,biological landscapes,meteorological and climatic landscapes.More importantly,in view of the blank area found in the statistical analysis,the paper analyzed the shrub landscapes on the basis of fi eld investigation,to support further research on the development and utilization of local ecotourism resources. 展开更多
关键词 ECOTOURISM Landscape resources Shrub landscape Mountain Western Sichuan
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To Protect the Environment—the Bounden Duty of CNPC
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作者 Zhang Xingfu 《China Oil & Gas》 CAS 2008年第2期19-21,共3页
Environmental Protection takes precedence during the production and operation The idea of 'humanistic, safety first and
关键词 保护环境 中油集团 天然气生产 环境保护 安全生产 责任 中石油 可持续发展
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The Report Card:Targets and Achievements
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作者 Lu WENBIN 《China Today》 2010年第11期28-29,共2页
CONSERVING resources and protecting the environment is a fundamental state policy of China. Measurable targets and monitored results are key yardsticks for work in emission reduction and resource thrift.
关键词 成绩 资源节约工作 保护环境 节约资源 监测结果 减排
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Speed up the Retrofit of Thermal Power Generating Units, Raise the Effectiveness of Power Plant Comprehensively
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作者 Jiang Zhesheng 《Electricity》 2000年第1期13-16,共4页
关键词 Speed up the Retrofit of Thermal Power Generating Units Raise the Effectiveness of Power Plant Comprehensively
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危险废物处理和掩埋场污染的整体危害分析
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作者 沈铎 王少泉 《世界环境》 1989年第4期40-43,共4页
本文论述的各种危险废物都是在危险废物处理和掩埋场最常见的,现在说明这些污染物是如何污染水、气、土壤等介质及通过各种暴露方式(吸收、吸入及皮肤接触)来危害人体健康的。本文概述的是美国环保局提供的目前经常使用的新方法。该方... 本文论述的各种危险废物都是在危险废物处理和掩埋场最常见的,现在说明这些污染物是如何污染水、气、土壤等介质及通过各种暴露方式(吸收、吸入及皮肤接触)来危害人体健康的。本文概述的是美国环保局提供的目前经常使用的新方法。该方法仅是为了识别和确定污染物的数量,以便说明污染物通过各种介质的转移,可作为环境法规及实施的依据来控制危险废物。 展开更多
关键词 危险废物处理 污染物排放 危害分析 污染水 化学物质 环境法规 有机砷 五氯苯酚 污染浓度 固体危险废物
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