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Pedosphere 2010年第1期20卷 104-110页

作者： gao hong-jian jianG Xin School of Resources and Environmental Science Anhui Agricultural University Hefei 230036 (China) State Key Lab of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China)

Adsorption and desorption are important processes that influence the transport, transformation, and bioavailability of hexachlorobenzene (HCB) in soils. To examine the adsorption-desorption characteristics of HCB, equilibrium batch experiments were carried out using two soils (red soil and paddy soil) with different initial HCB concentrations (0.25, 0.50, 0.75, 1.00, 1.50, 2.50, 3.50, and 5.00 mg L-1 ) by using 0.01 mol L-1 calcium chloride as the background solution. The successive desorption experiments (48, 96, 144, 192, and 240 h) were conducted after each adsorption equilibrium experiment. The results revealed that adsorption and desorption isotherms of HCB on two soils were nonlinear, which can be best described by the Freundlich equation with the square of the correlation coefficient (r 2 ) ranging from 0.97 to 0.99. Desorption of HCB from the two soils exhibited hysteresis at all HCB concentrations because the Freundlich desorption coefficients were always higher than the Freundlich adsorption coefficients. The hysteretic effect was enhanced with increasing initial HCB concentration, and positive hysteresis was observed at different concentrations.

关键词： Freundlich equation sorption coefficients sorption isotherms

High selectively oxidative bromination of toluene derivatives by the H_2O_2-HBr system

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Chinese Chemical Letters 2011年第4期22卷 382-384页

作者： Jie Ju Yu Jin Li jian Rong gao jian hong Jia Liang Han Wei jian Sheng Yi Xia Jia The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of TechnologyHangzhou 310032China

An aqueous solution of hydrogen peroxide and hydrogen bromide illuminated by a 60 W incandescent light bulb serves as a source of bromine *** substituted toluenes（NO2,Cl,Br,H,CH3） were high selectively brominated at the benzyl position for monobromination in CH2C12 at ice water with catalyst *** simple but effective bromination of toluene derivatives with an aqueous H2O2-HBr system is characterized with the use of inexpensive reagents and a lower impact on the environment, which make it a good alternative to the existing bromination methods.

关键词： Oxidative bromination Toluene derivatives H2O2-HBr

Residual Characteristics of Organochlorine Pesticides in Lou Soils with Different Fertilization Modes

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Pedosphere 2006年第2期16卷 161-168页

作者： WANG Fang BIAN Yong-Rong jianG Xin gao hong-jian YU Gui-Fen DENG jian-Cai State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 （China）.

Soll samples with three fertilization treatments （no fertilizer, corn straw and farm manure） collected from a Lou soil （Eum-orthic Anthrosol classfied using Chinese Soil Taxonomy） in northwestern China were analysed for residual levels and their characteristics of organochlorine pesticides （α-HCH, β-HCH,γ-HCH, δ-HCH, HCB, o, p＇-DDT, p, p＇-DDT, o, p＇- DDE, p,p＇-DDE, p,p＇-DDD, α-endosulfan, dieldrin and endrin）. Organochlorine pesticides （OCPs） were detected in all soil samples except δ-HCH and their total concentrations ranged from 159.31 ± 9.00 to 179.77 ± 2.58 ng g^-1 with an order of HCHs 〉 DDTs 〉（dieldrin ＋ endrin）〉 HCB 〉 α-endosulfan. Among all the compounds, γ-HCH had the highest concentration followed by p, p＇-DDE. The residual levels of HCH isomers and DDT as well as their metabolites in soil with different fertilization treatments were in the order of γ-HCH 〉β-HCH ≈ α-HCH 〉 δ-HCH and p,p’-DDE 〉 p, p’-DDT 〉 o,p＇-DDT 〉 p, p＇-DDD ≈ o, p＇-DDE, respectively. DDE/DDT ratios ranged from 1.59 ± 0.13 to 3.35± 0.16 and endrin/dieldrin ratios from 1.40 ±0.06 to 9.20± 4.05, both indicating no new occurrence of these pesticides in these soils, while α-HCH/γ-HCH ratios of 0.04 indicated a new input of lindane （almost pure γ-HCH） in the past several years. The farm manure treatments showed lower DDT residues than samples without fertilizer. Also addition of corn straw and farm manure increased soil organic matter content and decreased the soil pH which could retard the degradation of DDT in the soil.

关键词： Lou soil fertilization mode organochlorine pesticides residue

基于YOLOv5s的矿区地质灾害检测轻量化改进算法

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信息技术 2025年第2期49卷 46-54,60页

作者：贾永森林珍锋高建宏张喆续欣莹华晋焦煤有限责任公司山西吕梁033000 太原理工大学电气与动力工程学院太原030024

针对目前地质灾害检测领域存在检测算法复杂、计算量大与数据集匮乏等问题,文中提出了基于YOLOv5s改进的轻量化网络,并将所提网络在自制地质灾害数据集GDD1上进行训练测试。文中的最优改进方案是YOLOv5s-GhostNet-EIoU,采用Ghost Modul... 详细信息

针对目前地质灾害检测领域存在检测算法复杂、计算量大与数据集匮乏等问题,文中提出了基于YOLOv5s改进的轻量化网络,并将所提网络在自制地质灾害数据集GDD1上进行训练测试。文中的最优改进方案是YOLOv5s-GhostNet-EIoU,采用Ghost Module替换YOLOv5s网络中的部分卷积模块、C3Ghost替换YOLOv5s网络中的C3模块,大幅降低网络参数,并改进损失函数来弥补轻量化带来的精度损失。实验结果表明,YOLOv5s-GhostNet-EIoU网络mAP值达78.9%,相较于YOLOv5s基网络,模型体积压缩47.1%,计算量减小48.8%,参数量降低47.8%。该算法在保持YOLOv5s高检测精度的前提下,能够满足在无人机平台上的部署与实时检测的要求,实现了模型的轻量化。

关键词：矿区地质灾害目标检测 YOLOv5s 轻量化

Organochlorine pesticides in soils under different land usage in the Taihu Lake region, China

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Journal of Environmental Sciences 2007年第5期19卷 584-590页

作者： WANG Fang jianG Xin BIAN Yong-rong YAO Fen-xia gao hong-jian YU Gui-fen Jean Charles MUNCH Reiner SCHROLL State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Institute of Soil Ecology GSF-National Research Center for Environment and Health Neuherberg 85764 Germany

A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides （OCPs） were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX （DDD, DDE and DDT） had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p＇-（DDD＋DDE）/DDT in soils under three land usages were： paddy field 〉 tree land 〉 fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p＇-（DDD＋DDE）/DDT 〉1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.

关键词： DDT HCH land-use pesticide residue degradation

Effect of lanthanum on microstructure of a nickel-based single crystal superalloy

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China Foundry 2025年第1期22卷 55-64页

作者： hong gao Kai Guan Ren-jie Cui jian-chao Qin Zi-han Zhao Zhao-hui Huang Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China

To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are added to the *** microstructure of the nickel-based single crystal superalloy with trace of La was examined by means of SEM,EDS and *** show the addition of La decreases the segregation of elements and increases the amount ofγ/γ′eutectics of the as-cast alloy,and in the interdendritic region,the growth of eutectics is accompanied by the growth of strip clusters composed of Ni_(5)La and Ni_(3)*** the La content in the alloy increases,the proportion of Ni_(5)La in the cluster *** heat treatment,incipient melting occurs in the cluster regions,leading to an increase in microporosity compared to the original as-cast ***,the heat treatment alters the shape of the clusters from a strip morphology to an elliptical one,and it changes their composition from Ni_(5)La and Ni_(3)Ta to a combination of Ni_(5)La,Ni_(3)Ta,and MC carbides.

关键词： single crystal superalloy lanthanum microstructure heat-treatment precipitate phase

The Necessity of Teaching Oral Skills in the Classroom

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科技信息(学术研究) 2008年第25期 130-131页

作者： Yangzhou University gao jian hong Yangzhou Universiy

Today teaching oral communicative skills has gradually become an acknowledged approach in *** English teachers,we should create a spoken English learning environment and encourage students to practice *** paper advances the necessity of oral skills teaching in the *** teaching,we should be aware of the cultural differences between the east and the west and find appropriate methods to engage learners in appropriate *** we can achieve the final purpose of teaching the target language.

关键词： learning environment managing difficulties cultural differences appropriate topics

Residual Levels and New Inputs of Chlorinated POPs in Agricultural Soils from Taihu Lake Region

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Pedosphere 2005年第3期15卷 301-309页

作者： gaohong-jian jianGXin WANGFang BIANYong-Rong WANGDai-Zhang DENDjian-Cai YANDong-Yun InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）

Selected persistent organochlorine pesticides (OCPs), including 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its principal metabolites 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and 1,1-dichloro-2,2-bis(p-chlorophenyl)e- thane (DDD), hexachlorocyclohexane (HCH) and its isomers (α-,β-, γ-, and δ-HCH), hexachlorobenzene (HCB), endo- sulfan, dieldrin, and endrin were quantified to determine current levels of organochlorine pesticides, to assess the eco- toxicological potential, and to distin…

关键词： agricultural soils chlorinated persistent organic pollutants (POPs) new input residual levels Taihu Lake region

Thermal Characteristics of Optoelectronic Modules with DIP and BGA Package

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Semiconductor Photonics and Technology 2006年第1期12卷 43-46页

作者： gao hong-xia YU jian-zu XIE Yong-qi School of Aeronautic Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 CHN

In order to meet the electrical and thermal performance requirements of current high performance optoelectronics, two package types with dual-in-line package(DIP) and ball grid array(BGA) for optoelectronics are modeled and thermally simulated, their thermal characterizations are compared and discussed by using the temperature contours and the simulated heating characterization curves in free air and forced air ambient. The results show that BGA has superior inside and outside total performances, and has the promising future in the highly integrated optoelectronics.

关键词： Thermal performance DIP BGA Heating characterization Numerical simulation

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 54-59页

作者： Xiang-Qun Fu hong-Wei Li jian-hong Shi Tan Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering UniversityZhengzhou 450004China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

With the development of quantum computing technology,quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key *** paper designs a quantum trapdoor one-way function via EPR pairs and quantum *** on this,a new quantum public-key cryptosystem is presented,which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext *** with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition,which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs