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Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

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Journal of Environmental Sciences 2007年第7期19卷 864-873页

作者： SU Zhen-cheng zhang Hui-wen LI Xin-yu zhang Qin zhang cheng-gang Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China. Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.

关键词： agrochemicals acetochlor methamidophos toxic effects nifH gene PCR-DGGE

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寒冷地区住宅建筑立体绿化节点设计研究

智能建筑与智慧城市 2024年第5期 104-108页

作者：栾淏张成刚中国建筑西北设计研究院有限公司

文章对立体绿化节点进行研究,指出立体绿化设计要和建筑设计一体化,和建筑立面和谐和维护便利的三项原则。对立体绿化的节点构成从植物选择、基质土类型、给水系统、排水方式等方面介绍了节点设计的方法,并以工程实践的方式验证研究成... 详细信息

文章对立体绿化节点进行研究,指出立体绿化设计要和建筑设计一体化,和建筑立面和谐和维护便利的三项原则。对立体绿化的节点构成从植物选择、基质土类型、给水系统、排水方式等方面介绍了节点设计的方法,并以工程实践的方式验证研究成果的可行性,为寒冷地区建筑立体绿化技术提供了理论基础和实践经验,实现了该地区人居环境中立体绿化的设计完善与技术突破。

关键词：住宅建筑寒冷地区立体绿化技术研究

Soil Microbial Characteristics Under Long-Term Heavy Metal Stress:A Case Study in zhangshi Wastewater Irrigation Area,Shenyang

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Pedosphere 2008年第1期18卷 1-10页

作者： ZHANC Yan zhang Hui-Wen SU Zhen-cheng zhang cheng-gang Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 (China) Graduate School of the Chinese Academy of Sciences Beijing 100039 (China)

Soil samples were collected from zhangshi Wastewater Irrigation Area in the suburb of Shenyang City,China,an area with a 30-year irrigation history with heavy metal-containing *** chemical properties and microbial characteristics of the soils were examined to evaluate the present situation of heavy metal pollution and to assess the soil microbial characteristics under long-term heavy metal *** light of the National Environmental Quality Standards of China,the soil in the test area was heavily polluted by Cd and to a lesser degree by Zn and Cu,even though wastewater irrigation ceased in *** metabolic quotient (qCO_2) had a significant positive correlation,while soil microbial quotient (qM) had a negative correlation with content of soil heavy *** microbial biomass carbon (MBC) had significantly negative correlation with Cd,but soil substrate-induced respiration (SIR),dehydrogenase activity (DHA),cellulase activity, and culturable microbial populations had no persistent correlations with soil heavy metal *** nutrients,except for phosphorous,showed positive effects on soil microbial characteristics,which to a certain degree obscured the adverse effects of soil heavy *** Cd contributed more to the soil microbial characteristics,but qM and qCO_2 were more sensitive and showed persistent responses to heavy metals *** could be concluded that qM and qCO_2 can be used as bioindicators of heavy metal pollution in soils.

关键词： heavy metal stress metabolic quotient microbial biomass microbial quotient wastewater irrigation

Dynamic changes in microbial activity and community structure during biodegradation of petroleum compounds:A laboratory experiment

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Journal of Environmental Sciences 2007年第8期19卷 1003-1013页

作者： LI Hui zhang Ying KRAVCHENKO Irina XU Hui zhang cheng-gang Key Laboratory of Terrestrial Ecological Processes Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China. Winogradsky Institute of Microbiology Russian Academy of Sciences Moscow 117312 Russia

With 110-d incubation experiment in laboratory, the responses of microbial quantity, soil enzymatic activity, and bacterial community structure to different amounts of diesel fuel amendments were studied to reveal whether certain biological and biochemical characteristics could serve as reliable indicators of petroleum hydrocarbon contamination in meadow-brown soil, and use these indicators to evaluate the actual ecological impacts of 50-year petroleum-refining wastewater irrigation on soil function in Shenfu irrigation area. Results showed that amendments of ~ 1000 mg/kg diesel fuel stimulated the growth of aerobic heterotrophic bacteria, and increased the activity of soil dehydrogenase, hydrogenperoxidase, polyphenol oxidase and substrate-induced respiration. Soil bacterial diversity decreased slightly during the first 15 d of incubation and recovered to the control level on day 30. The significant decrease of the colony forming units of soil actinomyces and filamentous fungi can be taken as the sensitive biological indicators of petroleum contamination when soil was amended with 〉15000 mg/kg diesel fuel. The sharp decrease in urease activity was recommended as the most sensitive biochemical indicator of heavy diesel fuel contamination. The shifts in community structure to a community documented by Sphingomonadaceae within a-subgroup of Proteobacteria could be served as a sensitive and precise indicator of diesel fuel contamination. Based on the results described in this paper, the soil function in Shenfu irrigation area was disturbed to some extent.

关键词： petroleum hydrocarbons enzymatic activity bacterial diversity microbial community structure DGGE

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适用于网络新闻数据的未配对跨模态哈希方法

计算机与现代化 2024年第3期 54-60页

作者：武昭盟张成刚长春大学网络空间安全学院吉林长春130012 内蒙古民族大学计算机科学与技术学院内蒙古通辽028000

针对当前大部分跨模态哈希方法只能在提供完全配对的实例时才能训练,而不适用于现实世界中存在的大量未配对数据这一情况,提出一种基于网络新闻数据的未配对跨模态哈希方法。首先,构建特征融合网络处理未配对的训练数据,补充和完善模态... 详细信息

针对当前大部分跨模态哈希方法只能在提供完全配对的实例时才能训练,而不适用于现实世界中存在的大量未配对数据这一情况,提出一种基于网络新闻数据的未配对跨模态哈希方法。首先,构建特征融合网络处理未配对的训练数据,补充和完善模态信息,并采用对抗性损失加强学习的公共表示。其次,使用亲和矩阵对样本的特征分布和生成的二进制码进行优化,使样本之间的语义关系更加明确。最后,添加类别预测损失以提高二进制码的判别能力。在真实的网络新闻数据集上分别进行了配对场景和非配对场景的实验,实验结果表明了本文提出的方法具有扩展到实际应用中的能力。

关键词：跨模态哈希特征融合未配对数据对抗性学习

Crystal Structure and Theoretical Calculation of N-[4-(2-Methoxyphenoxy)]phenyl Acetanilide

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1077-1083页

作者： zhang cheng-gang LI Quan WANG Bi-Qin ZHAO Ke-Qing College of Chemistry and Material Science Sichuan Normal University Key Laboratory of Advanced Functional Materials Sichuan Higher Education System Chengdu 610066 China

N-[4-（2-Methoxyphenoxy）]phenyl acetanilide has been synthesized and its structure was determined by X-ray diffraction analysis with a = 0.6152（4）, b = 1.1728（4）, c = 1.2367（4） nm, α = 91.34（3）, β = 93.22（4）, γ = 102.61（3）°, V = 0.8688（7） nm3 and Dc = 1.274 Mg/m3. Theoretical investigations on the title compound were carried out by full optimization on its structural unit at the B3LYP/6-31G＊＊ level. And ultimately, the infrared, Raman spectra, electronic absorption spectra, and the relationships between temperature and thermodynamic functions （Hm, Sin, Cpm） were obtained.

关键词： phenyl acetanilide crystal structure spectra thermodynamic properties

Effect of Groundwater Irrigation on Soil PAHs Pollution Abatement and Soil Microbial Characteristics:A Case Study in Northeast China

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Pedosphere 2010年第5期20卷 557-567页

作者： zhang Jing zhang Hui-Wen zhang cheng-gang Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 (China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China)

To evaluate the effect of groundwater irrigation on the polycyclic aromatic hydrocarbons(PAHs) pollution abatement and soil microbial characteristics,a case study was performed in the Shenfu irrigation area of Shenyang,Northeast China,where the irrigation with petroleum wastewater had lasted for more than fifty years,and then groundwater irrigation instead of wastewater irrigation was applied due to the gradually serious PAHs pollution in *** chemical properties,including PAHs and nutrients contents,and soil microbial characteristics,including microbial biomass carbon,substrateinduced respiration,microbial quotient(qM),metabolic quotient(qCO2),dehydrogenase(DH),polyphenol oxidase(PO),urease(UR) and cellulase(CE) in surface and subsurface were *** organic C,total N,total P,and available K were significantly different between the sites *** PAHs concentrations ranged from 610.9 to 6362.8 μg kg-1 in the surface layers(0-20 cm) and from 404.6 to 4318.5 μg kg-1 in the subsurface layers(20-40 cm).From the principal component analysis,the first principal component was primarily weighed by total PAHs,total organic C,total N,total P and available K,and it was the main factor that influencing the soil microbial *** the tested microbial characteristics,DH,PO,UR,CE,qM and qCO2 were more sensitive to the PAHs stress than the others,thus they could serve as useful ecological assessment indicators for soil PAHs pollution.

关键词： microbial biomass paddy soil polycyclic aromatic hydrocarbons soil enzyme activities

Effects of Acetochlor and Methamidophos on Fungal Communities in Black Soils

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Pedosphere 2005年第5期15卷 646-652页

作者： LI Xin-Yu zhang Hui-Wen ZHOU Qi-Xing SU Zhen-cheng zhang cheng-gang Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang110016 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China）

Using plate counting and ergosterol assay, single and joint effects of acetochlor and methamidophos on the dynamicsof soil fungal population and total fungal biomass in the black soil zone of Northeast China were investigated. The resultsdemonstrated that acetochlor at high concentration levels (150 and 250 mg kg-1) had an acute and mostly chronic toxicityon both the soil fungal population and total fungal biomass, but at a low concentration (50 mg kg-1) generally had astimulating effect that was stronger with total fungal biomass than with the soil fungal population. Methamidophos ata high concentration level (250 mg kg-1) alone and almost all of its combinations with various dosages of acetochlorincreased the soil fungal population, whereas at most sampling dates with 250 mg methamidophos kg-1 soil, total fungalbiomass increased, but in combination with acetochlor it was decreased in the early period of incubation and then increased28 days after incubation. Thus, through measuring the number of colony forming unit of the soil fungal population alongwith the total fungal biomass, a better understanding on effects of agrochemicals on soil fungi could be made.

关键词： acetochlor black soil fungal biomass fungal population methamidophos

Long-term ocean temperature trend and marine heatwaves

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Journal of Oceanology and Limnology 2024年第4期42卷 1037-1047页

作者： Min zhang Yangyan cheng gang WANG Qi SHU Chang ZHAO Yuanling zhang Fangli QIAO First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Marine Sciences and Numerical Modelling Ministry of Natural ResourcesQingdao 266061China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and *** MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongly influences MHW *** a recent work suggesting that there should be a communicating baseline for long-term ocean temperature trends(LTT)and MHWs,we provided an effective and quantitative solution to calculate LTT and MHWs simultaneously by using the ensemble empirical mode decomposition(EEMD)*** long-term nonlinear trend of SST obtained by EEMD shows superiority over the traditional linear trend in that the data extension does not alter prior *** MHWs identified from the detrended SST data exhibited low sensitivity to the baseline choice,demonstrating the robustness of our *** also derived the total heat exposure(THE)by combining LTT and *** THE was sensitive to the fixed-period baseline choice,with a response to increasing SST that depended on the onset time of a perpetual MHW state(identified MHW days equal to the year length).Subtropical areas,the Indian Ocean,and part of the Southern Ocean were most sensitive to the long-term global warming trend.

关键词： marine heatwaves(MHWs) ensemble empirical mode decomposition(EEMD) long-term temperature(LTT)trend total heat exposure(THE)