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南水北调工程运行对河北省地下水位变化的影响研究

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水科学与工程技术 2024年第4期 18-21页

作者：杨春悦河北省保定水文勘测研究中心河北保定071000

为探讨南水北调工程对河北省平原区地下水位变化的影响,收集和分析不同时期的地下水位数据。研究结果显示:南水北调工程投入运行后,河北省地下水埋深整体呈现先下降后上升的趋势;不同地区和不同水文条件下的地下水位变化与南水北调工程... 详细信息

为探讨南水北调工程对河北省平原区地下水位变化的影响,收集和分析不同时期的地下水位数据。研究结果显示:南水北调工程投入运行后,河北省地下水埋深整体呈现先下降后上升的趋势;不同地区和不同水文条件下的地下水位变化与南水北调工程之间存在显著差异。综上所述,南水北调工程对河北省地下水位的影响是复杂而多样化的,确定南水北调工程对河北地下水位的恢复是积极的,研究结果对合理管理和保护河北省地下水资源具有重要意义。

关键词：南水北调地下水埋深河北省平原区地下水开发

浙江省山区县城乡融合测度时空特征及影响因素研究

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小城镇建设 2024年第4期42卷 5-13页

作者：杨纯玥郑国全浙江农林大学风景园林与建筑学院

文章以浙江省山区县为研究案例地,多维度构建了山区县城乡融合评价指标体系,运用熵权法确定浙江山区县城乡融合评价指标体系权重,使用标准差和变异系数对浙江省山区县2010—2020年城乡融合发展水平的时序演变特征进行评价,并在子系统层... 详细信息

文章以浙江省山区县为研究案例地,多维度构建了山区县城乡融合评价指标体系,运用熵权法确定浙江山区县城乡融合评价指标体系权重,使用标准差和变异系数对浙江省山区县2010—2020年城乡融合发展水平的时序演变特征进行评价,并在子系统层面作出时空特征分析,最后,采用时空地理加权回归模型(GWTR)分析主要影响因素的相关性。结果表明:1)浙江山区县城乡融合度呈现逐年上升的演变态势,区域内部各县域城乡融合度时空特征显著。2)城乡融合发展水平在空间融合层面改善最为明显,产业融合层面总体上呈现出整体增长的态势,在城乡要素融合和城乡治理融合方面整体发展水平偏低。3)城乡信息交流、城市空间扩张、劳动力流动、经济发展水平、城乡就业结构、山地覆盖率等因素对浙江山区县城乡融合发展水平的影响程度较大。

关键词：城乡融合时空特征影响因素浙江山区县

Rural-urban Migration, Rural Household Income and Local Geographical Contexts——A Case of Northwestern Guangxi, China

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Chinese Geographical Science 2008年第1期18卷 17-23页

作者： yang chunyue LU Qi XIE Lishuang Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Central University for Nationalities Beijing 100081 China

This paper aims to examine New Economics of Labor Migration (NELM) in the northwestern Guangxi, China and investigate the relationships among rural-urban migration, rural household income and local geographical contexts. Stratified sampling and typical case study were adopted and 236 questionnaires were collected from four vil- lages, Daxin, Lixin, Longhe and Yongchang. We analyzed the rural-urban migration rate, household income and local geographical factors, focusing on the ratio of remittance income to total household income. Data descriptions and sta- tistical methods, such as Pearson Chi-square test, Contingency coefficient, Eta, Pearson correlation coefficient, t-test, multiple comparisons (LSD test, Tamhane T2, Dunnett T3 and Dunnet C test) were used. The results are as follows. Rural households’ income is diversified in survey villages so the motivation of rural-urban migration in the study area can be partly explained by NELM. The migration rate of households (the percentage of households with migrants in survey households) in survey villages varies from 50% to 86%, while the proportion of remittance income to house- hold income is in the range of 30% to 80%. In the village of Yongchang, with the least average arable land area per household, the remittance income plays a vital role in household income (80%). And the statistical findings show that the proportion is significantly and negatively correlated with arable land area per household. The conclusion is that di- rect effect of migration, i.e., the contribution of remittance to household income, is negatively correlated with the con- tribution of resources to local income.

关键词： rural-urban migration household income local geographical contexts northwestern Guangxi

Rural-urban Migration,Rural Household Income and Sustainable Development in Rural Areas of China

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Chinese Journal of Population,Resources and Environment 2008年第2期6卷 70-73页

作者： Lu Qi yang chunyue Li Juan Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China The Commercial Press Beijing 100710 China

The objective of this paper is to investigate the rela- tionships among rural-urban migration,rural household income and sustainable development in rural areas of *** typical case study is done and 288 questionnaires are collected from five villages in Hebei and Guangxi provinces,*** migration and remittance status,household income and sustainable devel- opment of rural areas are analyzed on the basis of questionnaires. Rural-urban migration is becoming a part of routine life in rural *** remittance is an important component in rural house- hold ***-urban migration increases the arable land area per labor,which releases the tight human-land relationship in *** total,the migration increases the rural household in- come and accelerates the sustainable development of rural areas.

关键词： rural-urban migration rural household income sustainable development rural areas

Land use effects on the dynamics of soil C,N and microbes in the water-wind erosion crisscross region of the northern Loess Plateau,China

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Pedosphere 2024年第1期34卷 181-190页

作者： Yi WANG chunyue LI Shunjin HU State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh 27695USA

The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of different land use regimes on the dynamics of soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identify suitable land use types that can maintain soil fertility and sustainability. A field experiment was performed in Liudaogou watershed in Shenmu City, Shaanxi Province, China, where the dynamics of soil TOC and TN, microbial biomass C and N, microbial respiration, and net N mineralization in six typical land use types, dam land, rainfed slope land, deciduous broadleaf forest, evergreen coniferous forest, shrubland, and grassland,were measured in three different growing seasons. Land use type and season significantly affected TOC, TN, and the dynamics of microbial biomass and activity. As the most anthropogenically disturbed land use pattern, dam land was an optimal land use pattern for TOC sequestration due to its higher TOC and TN, but lower microbial activity. Soil TOC, TN, and microbial properties demonstrated a decreasing trend after natural grassland was converted to shrubland,forest, and rainfed slope land. Shrubland with exotic N-fixing Korshinsk peashrub(Caragana korshinskii Kom.) can maintain TOC, TN, and microbial properties similar to those in grassland. Soil TOC, NH_(4+)^(-)N, TN, moisture, and extractable C were the principal indexes for soil microbial biomass and activity and explained 88.90% of the total variance. Thus, grassland was the optimal land use pattern in the water-wind erosion crisscross region of the northern Loess Plateau to maintain ecosystem stability and sustainability.

关键词： grassland microbial activity microbial biomass total organic C total N watershed

The effect of rural labor migration on poverty alleviation:a village-level study in China

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Ecological Economy 2008年第3期4卷 282-289页

作者： yang chunyue Lu Qi Li Juan Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101P.R.China Graduate University Chinese Academy of Sciences Beijing 100049 P. R. China The Commercial Press Beijing 100710P.R.China

The construction of the new socialist countryside is being carried out in China nowadays. Although lots of successful experience has been gotten, different problems occur in various regions yet. To analyze the relationships among rural labor migration, poverty alleviation and characteristics of migrants is important in considering the effect of rural labor migration on the construction of the new. socialist countryside, Available sampling and typical case study are adopted and 236 questionnaires are collected from four villages in northwest GuangxL China, Daxin, Lixin, Longhe and Yongehang, We analyze the rural labor migration status, characteristics of migrants, remittance situation and income, household income and the ratio of remittance income to total household income. About 2/3 of the households have migrants in surveyed villages. And nearly half of the migration households have only one family member as migrants in the four villages. The migrants mainly comprise male and the younger, with the education level of junior middle school and higher More than half of the migrants are employed in Guangdong Province. But the characteristics of migrants in Yongchang are more diverse. The rural labor migration in the village is extremely active and extensive. And over 60% of the household with family members as migrants have remittance income. The rate in Yongchang is extremely high （80%）, And the income of households with migrants getting remittance income is significantly higher than their counterparts. More than half of their income comes from remittance as far as the former kind of household is concerned And in Yongchang, the rate is nearly 80%. The conclusion is that rural labor migration is popular and extensive in lots of villages. And the migration and remittance play an important role in rural household income, especially in some poor villages. For this kind of village, the rural labor migration may be some ＂compulsory course＂ in rural development. And the rural

关键词： Rural labor migration Poverty alleviation Impact Village-level

A new tetracyclic triterpenoid from endophytic fungus Fusarium sporotrichioides

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Chinese Herbal Medicines 2024年第2期16卷 231-234页

作者： Yajing Wang chunyue Liu Yihui yang Chang Li Yuehu Pei Department of Medicinal Chemistry and Natural Medicine Chemistry College of PharmacyHarbin Medical UniversityHarbin 150081China

Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological ***: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR(1H-NMR and13C-NMR) and 2D NMR(1H–1H COSY,HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD ***: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L(1), 12aacetoxy-4,4-dimethyl-24-methylene-5a-cholesta-8,14-diene-2a,3β,11β-triol(2), 12a-acetoxy-4,4-dime thyl-24-methylene-5a-cholesta-8-momoene-2a,3β,11β-triol(3), 12a-acetoxy-4,4-dimethyl-24-methy lene-5a-cholesta-8,14-diene-3β,11β-triol(4), and 12a-acetoxy-4,4-dimethyl-24-methylene-5acholesta-8-momoene-3β,11β-triol(5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 ***: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus ***. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on Hep G-2 cells than the other compounds, with IC50values of(2.8 ± 0.1) and(6.3 ± 0.3) μmol/L respectively.

关键词： antitumor Fusarium sporotrichioides integracide L tetracyclic triterpenoid 12a-acetoxy-4,4-dimethyl-24-methylene5a-cholesta-814-diene-2a,3b,11b-triol 12a-acetoxy-4,4-dimethyl-24-methylene5a-cholesta-8-momoene-2a,3b,11b-triol 12a-acetoxy-4,4-dimethyl-24-methylene5a-cholesta-8-momoene-3b,11b-triol

Deciphering TADF Mechanisms in Metal-Free Organic Emitters BrA-HBI:Utilizing Optimally Tuned Range-Separated Functionals for Insight

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Chinese Physics Letters 2024年第9期41卷 28-37页

作者： chunyue Yu Hang Yin Jie Guo Wentian Zhang Ying Shi Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently,Shao et *** a novel excited state intramolecular proton transfer(ESIPT)system BrA-HBI,demonstrating an emission quantum yield of up to 50%[***.32,2201256(2022)].However,many open issues cannot be answered solely by experimental means only and require detailed theoretical *** instance,what causes the activation of TADF from the Keto*tautomer and leads to fluorescence quenching in the Enol^(*)form?Herein,we provide a theoretical investigation on the TADF mechanism of the BrA-HBI molecule by optimally tuned range-separated *** findings reveal that ESIPT occurs in the BrA-HBI ***,we have disclosed the reason for the fluorescence quenching of the Enol^(*)form and determined that the T_(2)state plays a dominant role in the TADF *** addition,double hybrid density functionals method was utilized to verify the reliability of optimally tuned range separation functionals on the calculation of the TADF mechanism in *** findings not only provide a theoretical reference for development of highly efficient organic light-emitting diodes,but also demonstrate the effectiveness of the optimally tuned range-separated functionals in predicting the luminescence properties of TADF molecules.

关键词： optimal finding separated

Modulation of vagal activity to atria electrical remodeling resulted from rapid atrial pacing

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Journal of Geriatric Cardiology 2008年第3期5卷 159-163页

作者： Shulong Zhang Yingxue Dong Lianjun Gao Donghui yang chunyue Zhao Hongwei Zhao Xiaomeng Yin Jinqiu Liu Zhihu Lin Yanzong yang Department of Cardiology, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China Department of Cardiology The First Affiliated Hospital of Dalian Medical University

Background Atrial electrical remodeling(AER) plays an important role in the pathogenesis and maintenance of atrial ***,little is known about modulation of vagal activity to *** study aimed to investigate the relationship between vagal moduation and *** Twenty four adult mongrel dogs under general anesthesia were randomized into 3 *** activity was blocked by administration of metoprolol in 3 *** changes in vagal modulation to atria after AER were observed in 10 dogs without vagal interruption in group *** effects ofvagal intervention on AER were investigated in 8 dogs with administration of atropine in group *** impact of aggressively vagal activity on AER was studied in 6 dogs with bilateral cervical vag sympathetic trunks stimulation during AER in group *** cervical vagosympathetic trunks were decentralized. Multipolar catheters were placed into high right atria (RA),coronary sinus (CS) and right ventricle (RV).AER was induced by 600 bpm pacing through RA catheter for 30 *** effective refractory period (ERP) and vulnerability window (VW) of atrial fibrillation were measured with and without vagal stimulation before and after *** In group A,ERP decreased significantly at baseline and during vagal stimulation after AER compared with that before AER (all P0.05).In group C,ERP shortened significantly at baseline and vagal stimulation after AER compared with that before AER (all P<0.05).ERP shortening after AER in Groups A and C increased significantly than that in group B (all P<0.05).Atrial fibrillation could not be induced at baseline (VW close to 0) before and after AER in three *** became widen significantly during vagal stimulation after AER compared with that before AER in Groups A and C (all P<0.05),while VW remained unchanged in group B (V

关键词： atrial fibrillation vagus atrial electrical remodeling