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Journal of Mountain Science 2022年第4期19卷 945-957页

作者： BAI Yun-li FU Chao THAPA Balaram RANA Ram Bahadur zhang lin-xiu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China United Nations Environment Programme-International Ecosystem Management Partnership(UNEP-IEMP) Beijing 100101China Local Initiatives for Biodiversity Research and Development(LI-BIRD)PO Box 324Pokhara 33700Nepal

Agrobiodiversity conservation is vital for achieving sustainability, but empirical studies on the effects of different practices or measures on crop diversity are rare. This study aims to estimate the effects of raising conservation awareness(RCA),building diversity blocks(BDB), and their combination on crop diversity among 240 randomly selected households surrounding the Rupa Lake Watershed in Nepal. Based on descriptive analysis and multiple regression models, the results indicate that the two single measures had no significant effect on the numbers of crop species and varieties grown by households in 2018. However, the combination of RCA and BDB had a significantly positive effect on the number of crop varieties, especially for grain and vegetable crops. Considering that these crops are essential in the daily lives of local people, the results indicate that a strategy that combines both awareness raising and on-farm conservation measures can generate higher crop diversity and better serve the climate-resilient livelihoods of people in mountainous areas.

关键词： Agrobiodiversity Conservation measures Crop species and varieties Rupa Lake

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

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Rare Metals 2024年第1期43卷 236-246页

作者： lin Yang Zhong zhang Chao-Nan zhang xiu-Li Wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

农村儿童超重对学业表现的影响——基于CEPS数据的研究

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教育经济评论 2024年第2期9卷 85-109页

作者：王卫东郭帅安王会张林秀北京林业大学经济管理学院复旦大学高等教育研究所中国科学院地理科学与资源研究所

中国在减少儿童营养不良方面取得了巨大的成就。然而,农村儿童超重问题日趋凸显。目前超重对个体福利的影响并不清晰。本研究基于中国教育追踪调查数据(CEPS),实证揭示了超重对农村中学生学业表现的影响。结果表明,儿童超重显著降低了... 详细信息

中国在减少儿童营养不良方面取得了巨大的成就。然而,农村儿童超重问题日趋凸显。目前超重对个体福利的影响并不清晰。本研究基于中国教育追踪调查数据(CEPS),实证揭示了超重对农村中学生学业表现的影响。结果表明,儿童超重显著降低了其学业成绩。这种影响在父母受教育程度低、家庭经济条件差以及寄宿的儿童间更为凸显。探究机制发现,儿童超重会影响父母对其教育期望、教育投资及其与子女间的互动,降低儿童自身的教育期望及努力程度,影响儿童的心理健康以及社交质量。本研究一方面丰富了当前农村儿童人力资本形成的文献,另一方面也为致力于打破贫困代际传递的政策制定提供了有益启示。

关键词：超重农村儿童学业表现机制分析

Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao zhang Yu-Hai zhang Ying Zou xiu-xiu Yang Gen zhang Feng-Shou zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

The power of informal institutions:The impact of clan culture on the depression of the elderly in rural China

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Journal of Integrative Agriculture 2021年第4期20卷 1107-1118页

作者： LIU Xiao-hong WANG Wei-dong zhang lin-xiu China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871P.R.China School of Economics and Management Beijing Forestry UniversityBeijing 100083P.R.China UN Environment-International Ecosystem Management Partnership(UNEP-IEMP) Beijing 100101P.R.China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China

Exploration of ways to improve the subjective welfare of residents is an important area of current academic *** data from the China Family Panel Studies survey conducted in 2010,this paper investigated the impact of clan culture on the mental health of elderly people in rural *** results demonstrated that clan culture can significantly decrease the depression score of the rural ***,there was no gender difference with respect to the impact of clan culture on the depression score of the *** the same time,the positive effects of clan culture on the depression score of the elderly have gradually weakened with economic *** of the mechanisms involved indicated that in areas with stronger clan culture,older people receive more social *** study enriches our understanding of the impact of informal institutions on the welfare of rural *** the same time,it can also provide a certain decisionmaking reference for the government to formulate relative poverty relief strategies in a new stage of poverty alleviation.

关键词： clan culture the elderly depression rural China social support

A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： Qiong zhang lin-Lv lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

A Detailed Thermal Resistance Network Analysis of FCBGA Package

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Journal of Thermal Science 2024年第1期33卷 18-28页

作者： DANG Hao LU Yang DU Yanzheng zhang xiu zhang Qian MA Weigang zhang Xing Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Zhongxing Telecom Equipment Corporation Shanghai 201203China

Using thermal models to describe the heat dissipation process of FCBGA is a significant topic in the field of ***,the thermal resistance model considering the structure of each part of the chip is still ambiguous and rare,but it is quite desirable in *** this work,we propose a detailed thermal resistance network model,and describe it by using thermal conduction resistance and thermal spreading *** a striking FCBGA case,we calculated the thermal resistance of each part of the structure according to the temperature field simulated by *** thermal resistance network can be used to predict the temperatures in the chip under different *** example,when the power changes by 40%,the relative error of junction temperature prediction is only 0.24%.The function of the detailed thermal resistance network in evaluating the optimization space and determining the optimization direction is *** work illustrates a potential thermal resistance analysis method for electronic devices such as FCBGA.

关键词： FCBGA package thermal resistance network thermal spreading resistance junction temperature

Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model

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Research in Astronomy and Astrophysics 2024年第4期24卷 271-286页

作者： Yong-Xiong zhang Wen-xiu Guo Xiao-Ping Lu Hua Zheng Hai-Bin Zhao Jun Tian Wei-lin Wang School of Engineering Guangzhou College of Technology and BusinessGuangzhou 510850China School of Computer Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China School of Mathematics and Statistics Shaoguan UniversityShaoguan 512099China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryCASNanjing 210023China

Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally *** paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate *** PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore *** PDE algorithm accurately derives period and pole values from simulated *** analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole *** PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data *** work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.

关键词： methods:numerical minor planets asteroids:general techniques:photometric astrom

Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons

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Biomedical and Environmental Sciences 2024年第5期37卷 479-493页

作者： LI Yang lin Dan zhang xiu Qin JU Guang xiu SU Ya zhang Qian DUAN Hai Ping YU Wei Sen WANG Bing ling PANG Shu Tao Department of Epidemiology and Health Statistics School of Public HealthQingdao UniversityQingdao 266021ShandongChina Department of Environmental Health Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Physicochemical Laboratory Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Section of Child Health Care Huangdao Maternity and Child Health Care Hospital of QingdaoQingdao 266499ShandongChina Qingdao Blood Center Qingdao 266071ShandongChina

Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal *** Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old ***,37 children were categorized into low-and high-exposure groups based on the sum of the ten ***-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine ***,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina *** The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide ***,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in *** Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived *** investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes.

关键词： Child Gut microbiota Non-targeted metabolomics Polycyclic aromatic hydrocarbons Urinary metabolite profile

Status and path of intergenerational transmission of poverty in rural China:A human capital investment perspective

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Journal of Integrative Agriculture 2021年第4期20卷 1080-1091页

作者： BAI Yun-li zhang lin-xiu SUN Ming-xing XU Xiang-bo Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China UN Environment Programme-International Ecosystem Management Partnership Beijing 100101P.R.China

This paper focused on the intergenerational transmission of poverty in rural China by estimating the intergenerational transmission of earnings and stated its mechanism from the perspective of human capital investment before children participated in the labor *** data used in this study were longitude data collected in 2000 households of 100 villages among 25 counties across five provinces in 2005,2008,2012,2016,and *** and quantitative methods were *** found a significant intergenerational transmission of earnings in rural China,especially for the pairs of father–children and parents–*** intergenerational earnings'elasticities were much less than those in urban areas,which indicated better social mobility in rural areas than that in urban *** children with parents who could earn much were more likely to be invested before they participated in the labor market,gain a high education and have more *** cases further showed that the mechanism of human capital investment in children breaking the intergenerational transmission of poverty and promoting social mobility.

关键词： poverty intergenerational transmission human capital rural China