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天然和热活化蛏子壳粉对污染土壤中Cd赋存形态的影响

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环境科学研究 2018年第5期31卷 935-941页

作者：张盼杜立宇吴岩梁成华王沛文郭炜辰孙铭泽沈阳农业大学土地与环境学院辽宁沈阳110866 农业部东北耕地保育重点实验室辽宁沈阳110866 土肥资源高效利用国家工程实验室辽宁沈阳110866

为实现对Cd污染农田土壤的安全利用,通过室内培养试验,阐明天然蛏子壳粉、600℃热活化蛏子壳粉和800℃热活化蛏子壳粉在不同添加比例下对外源污染棕壤土中Cd赋存形态随时间变化的影响.结果表明,土壤p H随蛏子壳粉添加量的增加而增加,且... 详细信息

为实现对Cd污染农田土壤的安全利用,通过室内培养试验,阐明天然蛏子壳粉、600℃热活化蛏子壳粉和800℃热活化蛏子壳粉在不同添加比例下对外源污染棕壤土中Cd赋存形态随时间变化的影响.结果表明,土壤p H随蛏子壳粉添加量的增加而增加,且不同蛏子壳粉在同一添加比例下随培养时间延长呈平稳下降趋势,但都明显高于对照.在整个培养期间,可交换态Cd呈现先升高后降低的趋势,同时各处理不同程度地提高了碳酸盐结合态、铁锰结合态、有机结合态和残渣态Cd的含量.培养60 d后,各处理组对Cd形态转化的贡献率为800℃热活化蛏子壳粉>600℃热活化蛏子壳粉>天然蛏子壳粉,且三者使土壤中可交换态Cd含量分别降低了52.0%~67.1%、40.7%~45.7%、3..6%~43.6%.由土壤p H与土壤可交换态Cd含量的相关性分析表明,在培养5 d时,二者呈显著负相关关系,其余时期均呈极显著负相关关系.土壤p H是影响重金属离子发生吸附、解吸、络合和共沉淀的重要因素.研究显示,蛏子壳粉对污染土壤中Cd在有效性和形态转化方面起到一定的积极作用,从而为Cd污染土壤的修复利用提供了新的思路.

关键词： Cd污染蛏子壳粉赋存形态

RESEARCH ABOUT CONCRETE REGRESSION STRENGTH EQUATION BASED ON NONDESTRUCTIVE EXAMINATION

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RESEARCH ABOUT CONCRETE REGRESSION STRENGTH EQUATION BASED O...

第三届国际岩石力学与工程新进展学术会议暨城市规划与土木工程的三亚论坛

作者： HE FAN Department of civil Engineering,shenyang University of Technology,shenyang 110178,{3. ZE FAN Department of jewel,Liaoning Geology Engineering Vocational college,Dandong,118008,{3.

The proposed corrected regression strength equation with nondestructive parameter-entity strength is based on standard regression strength equation which is established through standard curing experimental *** regression strength equation is adopted correction factor to deduce structural entity *** to nondestructive check of field project,entity strength calculated from modified strength equation is accord with measured *** regression strength equation gives reference to regional strength equation.

关键词： RESEARCH ABOUT CONCRETE REGRESSION STRENGTH EQUATION BASED ON NONDESTRUCTIVE EXAMINATION

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不同底质条件下苦草根部细菌群落的组装模式

水资源保护 2024年第4期40卷 109-117页

作者：张文龙王新梓潘沈阳周鹏程李轶河海大学浅水湖泊综合治理与资源开发教育部重点实验室江苏南京210098 河海大学环境学院江苏南京210098

通过室内试验模拟不同底质条件,研究了苦草根部细菌群落的组装模式和功能变化。结果表明:底质条件的改变对苦草根际细菌群落产生了显著影响(p=0.003.,特别是在添加有机质和植物根际促生菌的底质条件下;尽管根际细菌群落与根内生菌群落... 详细信息

通过室内试验模拟不同底质条件,研究了苦草根部细菌群落的组装模式和功能变化。结果表明:底质条件的改变对苦草根际细菌群落产生了显著影响(p=0.003.,特别是在添加有机质和植物根际促生菌的底质条件下;尽管根际细菌群落与根内生菌群落存在较强联系,但根内生菌群落组装过程拥有更高的确定性,而根际细菌群落组装过程更易受到植物宿主以外叠加的环境因素影响;功能预测结果表明在添加有机质和植物根际促生菌的条件下,苦草根部细菌群落拥有更高的代谢活性,更有利于有益细菌群落在苦草根部的富集。

关键词：底质条件苦草根际细菌群落根内生菌群落组装模式

维普期刊数据库博看期刊

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SBS改性沥青路面经济效益和应用前景分析

沈阳大学学报 2004年第6期16卷 52-53页

作者：王晓初朱浮声王奕鹏东北大学资源与土木工程学院辽宁沈阳110004 辽宁省交通勘测设计院辽宁沈阳110004

结合丹东—本溪高速公路工程,对采用SBS改性沥青的路面的经济效益进行了分析,认为SBS改性沥青比普通沥青针入度下降,软化点提高,高温稳定性增强,车辙现象减少,脆点降低,低温延度增加,低温开裂减少,从而延长了路面寿命,其结论可供类似工... 详细信息

结合丹东—本溪高速公路工程,对采用SBS改性沥青的路面的经济效益进行了分析,认为SBS改性沥青比普通沥青针入度下降,软化点提高,高温稳定性增强,车辙现象减少,脆点降低,低温延度增加,低温开裂减少,从而延长了路面寿命,其结论可供类似工程项目参考·

关键词：改性沥青经济效益应用前景

Research on Concrete Filled Circular CFRP-steel Tubular Flexural Members:Experimental Study

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中国钢结构协会结构稳定与疲劳分会2.06年学术交流会暨钢结构教学研讨会

作者： WU Bin, WANG Qingli, YIN Chunxiao, JIA Lianguang (college of civil Engineering, {2. Jianzhu University, {2., Liaoning, P.R.china, 110168)

8 concrete filled circular CFRP-steel tubular flexural members and 2.concrete filled circular steel tubular flexural members are experimentally investigated. It is found that the load - middle span deflection curves for members with longitudinal CFRP can be defined as the following stages: elastic, elasto-plastic and softening stage and that for members without longitudinal CFRP is similar to that of the concrete filled steel tubular flexural members. Within the factors scope of this test, 1 layer circumferential CFRP only has no significant influence on load bearing capacity of the concrete filled steel tubular flexural members. The ductility of the concrete filled circular CFRP-steel tubular flexural members is better than that of the concrete filled circular FRP tubular flexural members.

关键词： concrete filled CFRP-steel tube steel tube FRP tube flexural members experimental study load-deflection curve load bearing capacity

Allelopathic interference of the essential oil from wild oat (Avena fatua) and crabgrass (Digitaria sanguinalis) with wheat (Triticum aestivum)

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Allelopathic interference of the essential oil from wild oat...

中国第五届植物化感作用学术研讨会

作者： ZHOU Bin 1,WANG Peng 1,KONG Chui-Hua 2.1 Institute of Applied Ecology,Chinese Academy of Sciences,shenyang 110016,china 2.{2. of {3. and Environmental Sciences,china Agricultural University,Beijing 100193.china

Crop-weed allelopahtic interactions may be mediated by the volatile allelochemicals released from crop,weed or *** this study,we analyzed chemical constituents of the essential oils from two weeds wild oat (Avena fatua) and crabgrass (Digitaria sanguinalis) and to evaluate their effects on the growth and allelochemical production of wheat (Triticum aestivum).Subsequently,we identified 51 constituents in the essential oil of crabgrass and 2. chemical constituents in that of wild oat by means of GC and GC-MS combination *** crabgrass the main constituent was hexadecyl-oxirane ( 9.04 %).And Henicosane (15.05 %) was the lagest one presented in wild *** the oils affected the growth of wheat with different growth media including water,soil and *** highest shoot dried weight inhibition rate is 2..58 % with the the aqueous solution of volatile oil on filter,and in soil root dried weight inhibition rate arrives at 3..43.%.In particular,the biomass allocation of wheat was changed greatly in aqueous growth ***,the oil of crabgrass changed biomass allocation more significantly than wild oat ***,the essential oils of two weeds induced the production of allelochemical DIMBOA (2.4-Dihydroxy-7-methoxy-1,4Benzoxazin-3.one) in *** DIMBOA content in wheat changed with the induction *** increase was observed at early induction time then declined *** the increase of the induction time,the DIMBOA content in wheat *** the time of 2.h,DIMBOA content wheat exposed to the volatiles of crabgrass or wild oat arrived at the *** points of them were 0.47 mg/g and 0.48 mg/g *** to the plain air the highest DIMBOA content of wheat was 0.3. mg/*** results suggested that allelopathic interference of the essential oils from wild oat and crabgrass with wheat occurred not only on biomass allocation but also on allelochemical production.

关键词：

层次分析法在衡水湖环境功能区划方案遴选中的应用

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水资源保护 2005年第1期21卷 27-28,44页

作者：潘增辉刘文娟周清张晓燕河北省水利科学研究院河北石家庄050051 中国农业大学水利与土木工程学院北京100083 宁夏水利学校宁夏银川750004

通过对环境、社会和技术经济的综合分析,利用层次分析法对衡水湖环境功能区划备选方案进行遴选,确定了最佳方案为:东洼蓄当地水,西洼蓄引江水,不建中隔堤,提高了评价结果的直观性和可操作性。

关键词：层次分析法湖泊功能区划衡水湖

Research on Concrete Filled Circular CFRP-steel Tubular Flexural Members:Theoretical Analysis

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Research on Concrete Filled Circular CFRP-steel Tubular Flex...

中国钢结构协会结构稳定与疲劳分会2.06年学术交流会暨钢结构教学研讨会

作者： XIE Guangpeng, WANG Qingli, GAO Jianzhi, JIA Lianguang (college of civil Engineering, {2. Jianzhu University, {2., Liaoning, P.R.china, 110168)

Some static performances for concrete filled circular CFRP-steel tubular flexural members were analyzed. It was found that the steel tube and CFRP tube could cooperate circumferentially and longitudinally from 0 load till the ultimate load bearing capacity. Circumferential strain does not distribute uniformly: circumferential tension strain at the point with the biggest longitudinal compression strain is the biggest and circumferential compression strain at the point with the biggest longitudinal tension strain is the smallest. For a same point, if it is compressed longitudinally, then tensioned circumferentially and vice versa. Steel tube longitudinal strain along the cross-section depth obeys the plain section assumption from 0 load till about 0.7 times the ultimate load bearing capacity. For members with the same steel tube outer diameter, steel tube longitudinal strain decrease as longitudinal CFRP layers increase at the same load level but their longitudinal strain are the same approximately when yielding. The deflection decreases as the longitudinal CFRP layers increase at the same load level and the longitudinal CFRP would enhance members’ rigidity significantly. For specimens with the same steel tube confinement factor, the more the longitudinal CFRP layers, the larger the ultimate load bearing capacity. Ultimate load bearing capacity enhancement ratio increases as the longitudinal CFRP layers increase for members with the same steel tube outer diameter.

关键词： circular CFRP-steel tube concrete filled flexural members static performance cooperation strain plain section assumption deflection ultimate load bearing capacity ultimate load bearing capacity enhancement ratio

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水电工程保险市场参与主体行为研究

水电能源科学 2010年第9期28卷 114-116页

作者：陈述郑霞忠郭洁郭巍三峡大学水利与环境学院湖北宜昌443002 武汉大学水利水电学院湖北武汉430072 武汉工业学院土木工程与建筑学院湖北武汉430023

针对水电工程保险市场参与主体行为影响水电工程保险市场健康发展,利用信息经济学分析了我国水电工程保险市场的信息不对称现象,建立了投保人与保险人的不完全信息静态博弈模型,提出促进工程保险在我国水电工程中应用的对策,以减少工程... 详细信息

针对水电工程保险市场参与主体行为影响水电工程保险市场健康发展,利用信息经济学分析了我国水电工程保险市场的信息不对称现象,建立了投保人与保险人的不完全信息静态博弈模型,提出促进工程保险在我国水电工程中应用的对策,以减少工程保险应用所带来的道德风险问题。

关键词：水电工程保险市场参与主体行为研究 Engineering Insurance 工程保险不完全信息静态博弈模型经济学分析不对称现象行为影响健康发展风险问题保险应用投保人保险人对策道德