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Detection of Cyanide in Pollution-free Livestock Product Breeding Water by Ion Chromatography 被引量:3
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作者 Dongya HUANG Youkai PENG Jinting YAN 《Asian Agricultural Research》 2018年第1期34-36,共3页
In order to verify the accuracy of ion chromatography for cyanide detection,optimization conditions were studied,and comparison was made for the detection results of cyanide between titration and isonicotinic acid pyr... In order to verify the accuracy of ion chromatography for cyanide detection,optimization conditions were studied,and comparison was made for the detection results of cyanide between titration and isonicotinic acid pyrazolone spectrophotometry. The results showed that ion chromatography has good linearity and reproducibility,with the recovery rate of 95%-105% and the limit of detection of 0. 001 mg/L. This method is simple,rapid,safe,selective,and suitable for the determination of cyanide in pollution-free livestock product breeding water. 展开更多
关键词 Ion chromatography TITRATION SPECTROPHOTOMETRY pollution-free livestock product breeding water CYANIDE
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Greenhouse Production Technical Procedure for Pollution-free Food
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作者 WANG Shao-wu LI Qing 《Asian Agricultural Research》 2012年第9期64-66,共3页
This procedure specifies production area environment, production technology, prevention and control of plant diseases and insect pests, and production files of pollution-free foods by taking tomato as an example. This... This procedure specifies production area environment, production technology, prevention and control of plant diseases and insect pests, and production files of pollution-free foods by taking tomato as an example. This procedure is applicable to greenhouse production of pollution-free food in Shandong Province. 展开更多
关键词 pollution-free FOOD TOMATO TECHNICAL PROCEDURE
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Occurrence and Pollution-free Control of Apolygus lucorum in Winter Jujube
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作者 Linmao LI Xingyuan MEN +5 位作者 Baohua YE Yi YU Ansheng ZHANG Lili LI Sicong ZHANG Xianhong ZHOU 《Plant Diseases and Pests》 CAS 2012年第3期21-23,27,共4页
In recent years, Apolygus htcorum has become the main pest of winter jujube. It sucks juice of young parts of winter jujube and causes falling of buds and flowers, leaf perforations, deformities and fall- off of fruit... In recent years, Apolygus htcorum has become the main pest of winter jujube. It sucks juice of young parts of winter jujube and causes falling of buds and flowers, leaf perforations, deformities and fall- off of fruits, leading to serious economic loss. Considering the occurrence characteristics and control problems, the distribution, occurrence regularity, damage characteristics and outbreak reasons of A. lucorum are overviewed and analyzed in this paper, and the pollution-free control measures are also put forward. 展开更多
关键词 Winter jujube Apolygus lucorum OCCURRENCE pollution-free control
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Evaluation on Heavy Metal Pollution of Soil in Pollution-free Agricultural Product Bases in Guangxi
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作者 Minjun DENG Yan LUO 《Asian Agricultural Research》 2014年第7期63-65,共3页
Using data of 6 pollution-free agricultural product bases in Guangxi Zhuang Autonomous Region,this paper analyzed content of heavy metals,including arsenic(As),mercury(Hg),lead(Pb),cadmium(Cd),and chromium(Cr) in soil... Using data of 6 pollution-free agricultural product bases in Guangxi Zhuang Autonomous Region,this paper analyzed content of heavy metals,including arsenic(As),mercury(Hg),lead(Pb),cadmium(Cd),and chromium(Cr) in soil.After Pb,Cd,Cr,Hg and As content in soil is determined,it evaluated the pollution of soil using single factor pollution index method and Nemerow synthetic pollution index method in combination with evaluation standard of heavy metals in soil and grading standard for soil pollution.Analysis results indicate that As,Hg,Pb,Cd,Cr content is different in pollution-free agricultural product bases,but all conform to related standards and there is no standard exceeding problem.It is concluded that the quality of soil in pollution-free agricultural product bases is excellent,not polluted and completely meet requirements of evaluation standards,and suitable for developing pollution-free agricultural products. 展开更多
关键词 pollution-free AGRICULTURAL product BASES SOIL HEA
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Regional partitioning of agricultural non-point source pollution in China using a projection pursuit cluster model 被引量:3
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作者 XinHu LI ChengYi ZHAO +1 位作者 Bin WANG Garry FENG 《Journal of Arid Land》 SCIE 2011年第4期278-284,共7页
A projection pursuit cluster(PPC) model was used to analyze the regional partitioning of agricultural non-point source pollution in China.The environmental factors impacting the agricultural non-point source polluti... A projection pursuit cluster(PPC) model was used to analyze the regional partitioning of agricultural non-point source pollution in China.The environmental factors impacting the agricultural non-point source pollution were compiled into a projection index to set up the projection index function.A novel optimization algorithm called Free search(FS) was introduced to optimize the projection direction of the PPC model.By making the appropriate improvements as we explored the use of the algorithm,it became simpler,and developed better exploration abilities.Thus,the multi-factor problem was converted into a single-factor cluster,according to the projection,which successfully avoided subjective disturbance and produced objective results.The cluster results of the PPC model mirror the actual regional partitioning of the agricultural non-point source pollution in China,indicating that the PPC model is a powerful tool in multi-factor cluster analysis,and could be a new method for the regional partitioning of agricultural non-point source pollution. 展开更多
关键词 nonpoint pollution regional partitioning projection pursuit free search
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Studies on Heavy Metal Pollution in Soil-Plant System:A Review 被引量:9
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作者 Wang Haiyan Sun XiangyangCollege of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, P.R. China 《Forestry Studies in China》 CAS 2003年第1期55-62,共8页
Heavy metal pollution in soil-plant system is of major environmental concern on a world scale and in China in particular with the rapid development of industry. The heavy metal pollution status in soil-plant system in... Heavy metal pollution in soil-plant system is of major environmental concern on a world scale and in China in particular with the rapid development of industry. The heavy metal pollution status in soil-plant system in China, the research progress on the bioavailability of heavy metals (affecting factors, extraction methods, free-ion activity model, adsorption model, multivariate regression model, Q-I relationship, and compound pollution), and soil remediation are reviewed in the paper. Future research and monitoring is also discussed. 展开更多
关键词 heavy metal pollution soil-plant system BIOAVAILABILITY free-ion activity model adsorption model multivariate regression model compound pollution soil remediation
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基于F-B NCP函数的可行QP-free算法
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作者 朱笑荣 《泰山学院学报》 2012年第3期43-47,共5页
本文得到一种可行QP-free算法,引入ε-有效集策略使得每次迭代只需求解规模较小的线性方程组得到迭代方向,且方程组只包含工作集中的约束,其规模较原问题大大减小,同时不进行弧搜索,从而降低了运算量.
关键词 QP—free算法 可行性 ε-有效集
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Appraisal of pollution and health risks associated with coal mine contaminated soil using multimodal statistical and Fuzzy-TOPSIS approaches
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作者 Sumit Kumar Sonali Banerjee +4 位作者 Saibal Ghosh Santanu Majumder Jajati Mandal Pankaj Kumar Roy Pradip Bhattacharyya 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第5期101-115,共15页
The present study assesses the concentration,probabilistic risk,source classification,and dietary risk arising from heavy metal(HMs)pollution in agricultural soils affected by coal mining in eastern part of India.Anal... The present study assesses the concentration,probabilistic risk,source classification,and dietary risk arising from heavy metal(HMs)pollution in agricultural soils affected by coal mining in eastern part of India.Analyses of soil and rice plant indicated significantly elevated levels of HMs beyond the permissible limit in the contaminated zones(zone 1:PbSoil:108.24±72.97,CuSoil:57.26±23.91,CdSoil:8.44±2.76,CrSoil:180.05±46.90,NiSoil:70.79±25.06 mg/kg;PbGrain:0.96±0.8,CuGrain:8.6±5.1,CdGrain:0.65±0.42,CrGrain:4.78±1.89,NiGrain:11.74±4.38 mg/kg.zone 2:PbSoil:139.56±69.46,CuSoil:69.89±19.86,CdSoil:8.95±2.57,CrSoil:245.46±70.66,NiSoil:95.46±22.89 mg/kg;PbGrain:1.27±0.84,CuGrain:7.9±4.57,CdGrain:0.76±0.43,CrGrain:8.6±1.58,NiGrain:11.50±2.46 mg/kg)compared to the uncontaminated zone(zone 3).Carcinogenic and non-carcinogenic health risks were computed based on the HMs concentration in the soil and rice grain,with Pb,Cr,and Ni identified as posing a high risk to human health.Monte Carlo simulation,the solubility-free ion activity model(FIAM),and severity adjusted margin of exposure(SAMOE)were employed to predict health risk.FIAM hazard quotient(HQ)values for Ni,Cr,Cd,and Pb were>1,indicating a significant non-carcinogenic risk.SAMOE(risk thermometer)results for contaminated zones ranged from low to moderate risk(CrSAMOE:0.05,and NiSAMOE:0.03).Fuzzy-TOPSIS and variable importance plots(from random forest)showed that Ni and Cr were mostly responsible for the toxicity in the rice plant,respectively.A self-organizing map for source classification revealed common origin for the studied HMs with zone 2 exhibiting the highest contamination.The positive matrix factorization model for the source apportionment identified coal mining and transportation as the predominant sources of HMs.Spatial distribution analysis indicated higher contamination near mining sites as compared to distant sampling sites.Consequently,this study will aid environmental scientists and policymakers controlling HM pollution in agricultural soils near coal mines. 展开更多
关键词 Coal mine free ion activity model Monto Carlo Simulation pollution and Health risk Fuzzy-TOPSIS
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Process for improving the ladle free- opening rate for high aluminum steel in continuous casting 被引量:3
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作者 LIU Junzhan ZHOU Tongjun LUO Hui 《Baosteel Technical Research》 CAS 2015年第1期42-45,共4页
Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. Accor... Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. According to the real condition of 40 t ladle in steel-making plant of Baosteel Special Steel Company, previous works show that the key factors affecting the ladle free-opening rate of high aluminum steel in continuous casting are:sand material, accessories baking, ladle nozzle cleaning, the process and amount of adding sand, and the rate of argon stirring during refining. Therefore, improving the ladle filler sand quality, baking all of the raw materials, controlling the addition of ladle filler sand, cleaning the ladle nozzle, and optimizing argon stirring during the refining process can resolve the problem of a low ladle free-opening rate of high aluminum steel caused by the long ladle time of liquid steel. 展开更多
关键词 continuous casting high aluminum steel LADLE free - opening rate
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Development of Debris-free Laser Plasma Sources for EUV Lithography in CIOMP 被引量:1
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作者 CHEN Bo, NI Qi liang,CAO Jian lin (State Key Laboratory of Applied Optics,Changchun Institute of Optics, Fine Mechanics and Physics,Chinese Academy of Sciences, Changchun 130022, China) 《光学精密工程》 EI CAS CSCD 2001年第5期442-445,共4页
We have been developing debris-free laser plasma sources for EUV lithography since 1996. Two types of debris-free sources, such as cryogenic target and gas-puff target laser plasma sources, were designed and built up ... We have been developing debris-free laser plasma sources for EUV lithography since 1996. Two types of debris-free sources, such as cryogenic target and gas-puff target laser plasma sources, were designed and built up in CIOMP. EUV radiation spectra of the sources with a variety of targets have been obtained by different ways. 展开更多
关键词 EUV LITHOGRAPHY laser plasma DEBRIS - free CRYOGENIC TARGET gas - PUFF TARGET
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EXACT SOLUTION FOR RECTANGULAR SLAB WITH THREE EDGES SIMPLY-SUPPORTED AND OTHER FREE
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作者 YU TENGHAIDepartment of Mathematics 《内江师范学院学报》 1996年第2期1-7,共7页
In this paper,we give all-sided pastic analysis of the rectangular slab with three edges simply-supported and other free.Here we discuss the following four cases:(1)The uniformly distributedload over the area a slab.(... In this paper,we give all-sided pastic analysis of the rectangular slab with three edges simply-supported and other free.Here we discuss the following four cases:(1)The uniformly distributedload over the area a slab.(2).A concentrated load act at midpoint of free edges slab.(3)A concen-trated load act at the center a slab.(4)The line load act along free edge of slab. 展开更多
关键词 The RECTANGULAR SLAB with three EDGES simply - SUPPORTED and OTHER free have wide the use value. But up to now only find the EXACT solution that a concentrated load act at midpoint of free edye a slab. The EXACT solution of OTHER support force
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Influence of 10-(6-plastoquinonyl) decyltriphenylphosphonium on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced hyperglycemia
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作者 Aleksander A Agarkov Tatyana N Popova Yana G Boltysheva 《World Journal of Diabetes》 2019年第12期546-559,共14页
BACKGROUND It is known that under conditions of tissue tolerance to insulin,observed during type 2 diabetes mellitus(DM2),there is an increased production of reactive oxygen species.Moreover,the free radicals can init... BACKGROUND It is known that under conditions of tissue tolerance to insulin,observed during type 2 diabetes mellitus(DM2),there is an increased production of reactive oxygen species.Moreover,the free radicals can initiate lipid peroxidation(LPO)in lipoprotein particles.The concentration of LPO products can influence the state of insulin receptors,repressing their hormone connection activity,which is expressed as a reduction of the glucose consumption by cells.It is possible that reduction in glucose concentration during administration of 10-(6-plastoquinonyl)decyltriphenylphosphonium(SkQ1)to rats with DM2 may be related to the antioxidant properties of this substance.AIM To establish the influence of SkQ1 on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced hyperglycemia.METHODS To induce hyperglycemia,rats were fed a high-fat diet for 1 mo and then administered two intra-abdominal injections of streptozotocin with a 7-d interval at a 30 mg/kg of animal weight dose with citrate buffer equal to pH 4.4.SkQ1 solution was administered intraperitoneally at a 1250 nmol/kg dose per day.Tissue samples were taken from control animals,animals with experimental hyperglycemia,rats with streptozotocin-induced glycemia that were administered SkQ1 solution,animals housed under standard vivarium conditions that were administered SkQ1,rats that were administered intraperitoneally citrate buffer equal to pH 4.4 once a week during 2 wk after 1-mo high-fat diet,and animals that were administered intraperitoneally with appropriate amount of solution without SkQ1(98%ethanol diluted eight times with normal saline solution).To determine the intensity of free radical oxidation and total antioxidant activity,we used the biochemiluminescence method.Aconitate hydratase(AH),superoxide dismutase,and catalase activities were estimated using the Hitachi U-1900 spectrophotometer supplied with software.The amount of citrate was determined by means of the Natelson method.Real-time polymerase chain reaction was carried out using an amplifier ANK-32.RESULTS It was found that the mitochondrial-directed antioxidant elicits decrease of biochemiluminescence parameter values that increase by pathology as well as the levels of primary products of LPO,such as diene conjugates and carbonyl compounds,which indicate intensity of free radical oxidation.At the same time,the activity of AH,considered a crucial target of free radicals,which decreased during experimental hyperglycemia,increased.Apparently,increasing activity of AH influenced the speed of citrate utilization,whose concentration decreased after administering SkQ1 by pathology.Moreover,the previously applied antioxidant during hyperglycemia influenced the rate of antioxidant system mobilization.Thus,superoxide dismutase and catalase activity,as well as the level of gene transcript under influence of SkQ1 at pathology,were changing to the direction of control groups values.CONCLUSION According to the results of performed research,SkQ1 can be considered a promising addition to be included in antioxidant therapy of DM2. 展开更多
关键词 Diabetes mellitus free radical oxidation ANTIOXIDANTS 10-(6-plastoquinonyl)decyltriphenylphosphonium
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自贸试验区如何促进绿色发展——基于环境污染视角的实证研究
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作者 王三兴 欧阳鹏 《华北水利水电大学学报(社会科学版)》 2024年第4期27-37,共11页
有效减少环境污染是绿色发展的前提,也是实现绿色发展的关键。基于2009—2020年中国257个地级及以上城市的面板数据,采用多期双重差分法研究自贸试验区试点政策对城市环境污染的影响,构建中介效应模型分析产业结构高级化和绿色技术创新... 有效减少环境污染是绿色发展的前提,也是实现绿色发展的关键。基于2009—2020年中国257个地级及以上城市的面板数据,采用多期双重差分法研究自贸试验区试点政策对城市环境污染的影响,构建中介效应模型分析产业结构高级化和绿色技术创新的具体作用,同时运用空间杜宾模型检验自贸试验区试点的设立对环境污染的影响是否具有空间辐射效应。研究结果表明:自贸试验区试点政策有利于减少城市环境污染;自贸试验区试点政策从产业结构高级化和绿色技术创新这两个途径改善了城市环境状况;自贸区试点政策对环境污染的改善具有显著的空间辐射作用。 展开更多
关键词 自贸试验区 绿色发展 环境污染 多期双重差分 空间杜宾模型
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ICP-MS测定无公害农产品土壤样中的铅·镉 被引量:5
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作者 陈虹 张素珍 吴小均 《安徽农业科学》 CAS 北大核心 2010年第23期12509-12509,12513,共2页
[目的]简便快速测定无公害农产品土壤样中铅(Pb)、镉(Cd)的含量。[方法]采用湿法消解样品,在硝酸介质中用电感耦合等离子体质谱仪(ICP-MS)测定Pb、Cd的含量。[结果]在最佳测定条件下,Pb、Cd的质量分数分别在1.70~1000.00mg/kg、0.05~1... [目的]简便快速测定无公害农产品土壤样中铅(Pb)、镉(Cd)的含量。[方法]采用湿法消解样品,在硝酸介质中用电感耦合等离子体质谱仪(ICP-MS)测定Pb、Cd的含量。[结果]在最佳测定条件下,Pb、Cd的质量分数分别在1.70~1000.00mg/kg、0.05~100.00mg/kg范围内呈线性关系。相对标准偏差分别小于3.4%和5.2%。[结论]该法具有简便快速、检出限低等特点,可满足土壤样中Pb、Cd的测定。 展开更多
关键词 电感耦合等离子体质谱 无公害农产品土壤
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(K1,4;2)-图的闭包和周长 被引量:1
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作者 赵海霞 马巧灵 张苏梅 《山东师范大学学报(自然科学版)》 CAS 2010年第1期42-44,共3页
针对(K1,4;2)-图这一新的图类,证明了以下结论:1)设G是δ≥5且K1∨P4-free的(K1,4;2)-图,则c(G)=c(cl(G));2)设G是δ≥5且T3-free的(K1,4;2)-图,则c(G)=c(cl(G)).
关键词 闭包 (K1 p q)- HAMILTON图 F—free 局部连通点
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(K_(1,4);2)-图的3-闭包中的路 被引量:1
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作者 赵海霞 马巧灵 张苏梅 《科学技术与工程》 2010年第6期1333-1336,共4页
对(K1,4;2)-图,证明它的3-闭包的一个性质。G为{K1∨P5,T3}-free或K1∨P4-free的(K1,4;2)图,x,a,b为G中不同三点,x为G中局部3-连通的适宜点,G′由G在点x局部完备所得。若G′中有长为l的(a,b)-路,则G中有长为l的(a,b)-路。
关键词 k-闭包 (K1 P q)- F—free 局部k-连通图
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“蜂-蛙-灯”绿色生产技术对水稻害虫、天敌及产量的影响 被引量:10
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作者 刘功朋 张玉烛 +5 位作者 朱国奇 刘洋 陈恺林 黄志农 李超 方宝华 《湖南农业科学》 2013年第4期89-92,共4页
采用赤眼蜂、蛙类和诱虫灯等为主的集成防控措施,对水稻害虫和天敌种群发生的影响。结果表明:"蜂-蛙-灯"绿色生产技术对稻飞虱和稻纵卷叶螟有较好的控制效果,对蜘蛛和黑肩绿盲蝽影响较小或无影响,且"蜂-蛙-灯"防治... 采用赤眼蜂、蛙类和诱虫灯等为主的集成防控措施,对水稻害虫和天敌种群发生的影响。结果表明:"蜂-蛙-灯"绿色生产技术对稻飞虱和稻纵卷叶螟有较好的控制效果,对蜘蛛和黑肩绿盲蝽影响较小或无影响,且"蜂-蛙-灯"防治区的水稻产量与化学防治区无显著差异;随着该技术连续3年示范,稻飞虱和稻纵卷叶螟逐年减少,水稻产量逐年增加。该技术模式减少了化学药剂的使用,保护了生态环境,是一种新型的生态农业模式,具有广阔的推广应用情景。 展开更多
关键词 绿色生产技术 水稻 害虫 天敌 产量
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中国-东盟博览会对CAFTA建设的影响 被引量:1
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作者 周苹 《对外经贸实务》 北大核心 2009年第7期78-81,共4页
一、中国-东盟博览会概述 中国-东盟博览会是推动中国-东盟自由贸易区(China-AS—EAN Free Trade Area,以下简称CAFTA)建设的实质行动。2003年10月在第七次中国-东盟领导人会议上,中国国务院总理温家宝建议,从2004年起每年在中国... 一、中国-东盟博览会概述 中国-东盟博览会是推动中国-东盟自由贸易区(China-AS—EAN Free Trade Area,以下简称CAFTA)建设的实质行动。2003年10月在第七次中国-东盟领导人会议上,中国国务院总理温家宝建议,从2004年起每年在中国广西南宁举办中国-东盟博览会,同时建议同期举办中国-东盟商务与投资峰会。这一建议,得到了各国领导人的普遍欢迎和响应。 展开更多
关键词 中国-东盟博览会 CAFTA 中国-东盟自由贸易区 领导人会议 国务院总理 free EAN 温家宝
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过氧化物类芬顿体系修复有机污染物的研究进展
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作者 苟欢欢 刘慧博 +3 位作者 徐凯 李元昊 雷波 杨开静 《现代农业科技》 2024年第11期133-138,153,共7页
环境中有机污染物种类繁多,例如有机卤代物、有机农药和苯系物等。过氧化物常被作为自由基前驱体。过氧化物类芬顿系统是实现环境中有机污染物修复的有效技术手段,通过产生羟基等自由基将环境中有机污染物转化为易分解的小分子、CO_(2)... 环境中有机污染物种类繁多,例如有机卤代物、有机农药和苯系物等。过氧化物常被作为自由基前驱体。过氧化物类芬顿系统是实现环境中有机污染物修复的有效技术手段,通过产生羟基等自由基将环境中有机污染物转化为易分解的小分子、CO_(2)和H_(2)O。本文综述了部分学者对过氧化物类芬顿体系降解环境中有机污染物性能、影响因素的研究进展,阐述了过氧化物类芬顿体系存在的问题,以期为过氧化物类芬顿体系修复环境中有机污染物提供理论技术支撑。 展开更多
关键词 过氧化物 类芬顿体系 自由基 有机污染物 环境修复 影响因素
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无锡自抛光防污涂料研究进展
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作者 胡程颖 张凯 +3 位作者 张陆 王效军 刘术辉 桂泰江 《中国涂料》 CAS 2024年第3期24-29,共6页
海洋污损生物附着问题一直影响海洋运输与海洋工程行业的发展。为减轻海洋生物附着所带来的困扰,防污涂料被广泛应用,而无锡自抛光涂料(TFSPC)因其卓越的防污性能和低毒性而成为防污涂料市场的主流产品。详细探讨了无锡自抛光涂料的工... 海洋污损生物附着问题一直影响海洋运输与海洋工程行业的发展。为减轻海洋生物附着所带来的困扰,防污涂料被广泛应用,而无锡自抛光涂料(TFSPC)因其卓越的防污性能和低毒性而成为防污涂料市场的主流产品。详细探讨了无锡自抛光涂料的工作机理、成分组成以及目前的应用状况。 展开更多
关键词 海洋防污 机理 无锡自抛光防污涂料
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