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Journal of Systematics and Evolution 2009年第2期47卷 103-109页

作者： yuan HUANG chang-Qin ZHANG De-Zhu LI(Key Laboratory of Biodiversity and Biogeography,Kunming Institute of Botany,Chinese Academy of Sciences,Kunming 650204,China) Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

Omphalogramma souliei *** an endangered perennial herb only distributed in alpine areas of SW *** markers were applied to determine the genetic variation and genetic structure of 60 individuals of three populations of *** in NW Yunnan,*** genetic diversity at the species level is low with P= 42.5%(percentage of polymorphic bands) and Hsp=0.1762(total genetic diversity).However,a high level of genetic differentiation among populations was detected based on different measures(Nei’s genetic diversity analysis:Gst=0.6038;AMOVA analysis:Fst=0.6797).Low level of genetic diversity within populations and significant genetic differentiation among populations might be due to the mixed mating system in which xenog-amy predominated and autogamy played an assistant role in *** genetic drift due to small population size and limited current gene flow also resulted in significant genetic *** assessment of genetic variation and differentiation of the endangered species provides important information for conservation on a genetic *** strategies for this rare endemic species are proposed.

关键词： genetic differentiation genetic diversity ISSR markers mating system Omphalogramma souliei

The renewability and quality of shallow groundwater in Sanjiang and Songnen Plain, Northeast China

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Journal of Integrative Agriculture 2017年第1期16卷 229-238页

作者： ZHANG Bing SONG Xian-fang ZHANG Ying-hua HAN Dong-mei TANG chang-yuan YANG Lihi WANG Zhong-liang Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal University Tianjin 300387 P.R.China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P.R.China Departments of Environmental Science & Landscape Architecture Faculty of Horticulture Chiba University Chiba 271-8510 Japan

Groundwater is a key component for water resources in Sanjiang and Songnen Plain, an important agriculture basement in China. The quality and the renewability of irrigation groundwater are essential for the stock raising and agricultural production. Shallow groundwater was sampled and analyzed for various variables. The salinity sodium concentration and bicarbonate hazard, were examined with regard to the United States Department of Agriculture （USDA） irrigation water standards. The concentration of chlorofluorocarbons （CFCs） was determined to analyze the age of groundwater. Most groundwater samples labeled as excellent to good for irrigation with low salinity hazard or medium salinity hazard. Four groundwater samples were good and suspected for irrigation with high salinity hazard. Generally groundwater in Sanjiang Plain was younger than the groundwater in Songnen Plain. Meanwhile, groundwater nearby river is younger than the groundwater further away inside the watershed. The mean age of groundwater in Sanjiang Plain is in average of 44.1,47.9 and 32.8 years by CFC-11 （CCI3F）, CFC-12 （CCI2F2） and CFC-113 （C2CI3F3）, respectively. The mean ages of groundwater in Songnen Plain is in average of 46.1, 53.4, and 40.7 years by CFC-11, CFC-12 and CFC-113, respectively. Thus, groundwater nearby rivers could be directly exploited as irrigation water. Partial groundwater has to be processed to lower the salt concentration rather than directly utilized as irrigation water in Songnen Plain. Both water quality and renewability should be put in mind for sustainable agricultural development and water resources management.

关键词： groundwater irrigation water quality renewability agricultural development Sanjiang and Songnen Plain

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Aerobic oxidation of benzylic aldehydes to acids catalyzed by iron (Ⅲ) meso-tetraphenylporphyrin chloride under ambient conditions

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Chinese Chemical Letters 2007年第8期18卷 926-928页

作者： Xian Tai Zhou Hong Bing Ji Qiu Lan yuan Jian chang Xu Li Xia Pei Le Fu Wang School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China

Highly efficient aerobic oxidation of benzylic aldehydes to the corresponding acids catalyzed by iron （Ⅲ） meso-tetrapbenylporphyrin chloride （Fe（TPP）Cl） under ambient conditions was developed. The catalyst has been proved to be an excellent catalyst for the system in the presence of molecular oxygen and isobutryaldehyde at room temperature.

关键词： Benzylic aldehydes Oxidation Metalloporphyrins

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Automatic synthesis of advertising images according to a specified style

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Frontiers of Information Technology & Electronic Engineering 2020年第10期21卷 1455-1466页

作者： Wei-tao YOU Hao JIANG Zhi-yuan YANG chang-yuan YANG Ling-yun SUN Key Laboratory of Design Intelligence and Digital Creativity of Zhejiang Province Hangzhou 310027China International Design Institute Zhejiang UniversityHangzhou 310058China International User Experience Business Unit Alibaba GroupHangzhou 311121China

Images are widely used by companies to advertise their products and promote awareness of their *** automatic synthesis of advertising images is challenging because the advertising message must be clearly conveyed while complying with the style required for the product,brand,or target *** this study,we proposed a data-driven method to capture individual design attributes and the relationships between elements in advertising images with the aim of automatically synthesizing the input of elements into an advertising image according to a specified *** achieve this multi-format advertisement design,we created a dataset containing 13280 advertising images with rich annotations that encompassed the outlines and colors of the elements,in addition to the classes and goals of the *** our probabilistic models,users guided the style of synthesized advertisements via additional constraints(e.g.,context-based keywords).We applied our method to a variety of design tasks,and the results were evaluated in several perceptual studies,which showed that our method improved users’satisfaction by 7.1%compared to designs generated by nonprofessional students,and that more users preferred the coloring results of our designs to those generated by the color harmony model and Colormind.

关键词： Image dataset Data-driven method Automatic advertisement synthesis

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Enhancing the green efficiency of fundamental sectors in China’s industrial system:A spatial-temporal analysis

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Journal of Management Science and Engineering 2021年第4期6卷 393-412页

作者： Jiangxue Zhang Xu Liu Xue Zhang yuan chang changbo Wang Lixiao Zhang School of Economics and Resource Management Beijing Key Lab of SCI-TECH Strategy for Urban Green DevelopmentBeijing Normal UniversityBeijing100875China School of Business Harbin University of CommerceHarbin150028China School of Management Science and Engineering Central University of Finance and EconomicsBeijing100081China College of Economics and Management&Research Center for Soft Energy Science Nanjing University of Aeronautics and AstronauticsNanjing210016China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing100875China

Due to sectoral interactions in the economy,the overall green efficiency(GE)of China’s industrial system relies heavily on fundamental sectors that contribute substantial energy to the supply chain production of other sectors but shows low sectoral *** the three fundamental sectors in China’s industrial systems,namely the smelting and pressing of nonferrous metals(SPNFM),the processing of petroleum,coking,and nuclear fuel(PPCNF);and the manufacturing of nonmetallic mineral products(MNMMP),we employed a three-stage data envelopment analysis(DEA)model to measure GE in the fundamental sectors in 30 provinces from 2010 to *** then adopted a stochastic frontier analysis(SFA)model to evaluate the influence of technological innovation(TI),industrial agglomeration(IA),environmental regulation(ER),and intraindustry competition(IC).The results showed that GE in the three fundamental sectors varied ***,TI promoted GE in MNMMP,but the effect was not obvious in the SPNFM and PPCNF ***,ER had positive impacts on GE in the fundamental *** effects of IA and IC on GE in the fundamental sectors varied in direction and *** eliminating the impacts of environmental effects and statistical noise,the real GE in the three fundamental sectors varied significantly compared to the comprehensive *** opportunities for enhancing GE in the fundamental sectors mainly lie in region-specific policy and regulations that avoid a“one-size-fits-all”governance approach.

关键词： Fundamental sectors Green efficiency Three-stage DEA Spatial differences

Dielectric nanocomposites with superb high-temperature capacitive performance based on high intrinsic dielectric constant polymer

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Nano Research 2024年第9期17卷 8504-8512页

作者： Ding Ai yuan chang Haoliang Liu Chenglong Wu Yao Zhou Yuting Han Hao Yu Bing Xiao Yonghong Cheng Guanglei Wu Zirui Jia State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Materials for Energy and Environment State Key Laboratory of Bio-Fibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Advancements in power electronics necessitate dielectric polymer films capable of operating at high temperatures and possessing high energy *** significant strides have been achieved by integrating inorganic fillers into high-temperature polymer matrices,the inherently low dielectric constants of these matrices have tempered the magnitude of *** this work,we report an innovative nanocomposite based on sulfonylated polyimide(SPI),distinguished by the incorporation of sulfonyl groups within the SPI backbone and the inclusion of wide bandgap hafnium dioxide(HfO_(2))*** nanocomposite has demonstrated notable enhancements in thermal stability,dielectric properties,and capacitive performance at elevated *** simulations at both molecular and mesoscopic levels have elucidated the mechanisms behind these improvements,which could be attributed to confined segmental motion,an optimized electronic band structure,and a diminished incidence of dielectric breakdown ascribed to the presence of sulfonyl ***,the SPI-HfO_(2)nanocomposite demonstrates a high charge-discharge efficiency of 95.7%at an elevated temperature of 150℃and an applied electric field of 200 MV/***,it achieves a maximum discharged energy density of 2.71 J/cm^(3),signalling its substantial potential for energy storage applications under extreme conditions.

关键词： dielectric polymer nanocomposites high-temperature high dielectric constant sulfonyl groups energy storage performance

Hydrochemical characteristics and geochemistry evolution of groundwater in the plain area of the Lake Baiyangdian watershed,North China Plain

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Journal of Groundwater Science and Engineering 2018年第3期6卷 220-233页

作者： ZHANG Yu-qin WANG Guang-wei WANG Shi-qin yuan Rui-qiang TANG chang-yuan SONG Xian-fang Key Laboratory of Agricultural Water Resources Hebei Laboratory of Agricultural Water-SavingCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China University of Chinese Academy of Sciences Beijing 100049China Faculty of Horticulture Chiba UniversityMatsudo-city271-8510Japan School of Environmental Sciences&Resources Shanxi UniversityTaiyuan 030006China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Water cycle and water quality in the Lake Baiyangdian watershed of the North China Plain have undergone great changes due to over-pumping of groundwater and wastewater *** this paper,hydrogeochemical data was collected to analyze the hydrochemical characteristics and geochemistry evolution of *** study area was divided into two typical *** was in the upstream plain area,where over-pumping had resulted in significant decline of groundwater level;the other one was located in the downstream area near the Fu River and Lake Baiyangdian(Lake BYD region).In addition to the natural weathering of minerals,excessive fertilizer was also a main factor of higher ion concentration in *** to studies,due to good permeability,these regions were easy to be polluted even with deep groundwater ***,upstream shallow groundwater and surface water,including lake water,domestic along with industrial wastewater were all sources of present shallow groundwater in the Lake BYD *** indicated that anthropogenic activities rather than minerals much matter to the groundwater in these ***,wastewater largely decided the groundwater quality,which suggested that the management and restoration of surface water quality was crucial to groundwater protection.

关键词： Hydrochemical characteristics Geochemical processes Groundwater The Lake Baiyangdian Watershed North China Plain

Coordinated flight control of miniature fixed-wing UAV swarms: methods and experiments

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Science China(Information Sciences) 2019年第11期62卷 134-150页

作者： Xiangke WANG Lincheng SHEN Zhihong LIU Shulong ZHAO Yirui CONG Zhongkui LI Shengde JIA Hao CHEN Yangguan YU yuan chang Yajing WANG College of Mechantronics and Automation National University of Defense Technology College of Engineering Peking University

In this paper, we present our recent advances in both theoretical methods and field experiments for the coordinated control of miniature fixed-wing unmanned aerial vehicle(UAV) swarms. We propose a multi-layered group-based architecture, which is modularized, mission-oriented, and can implement large-scale swarms. To accomplish the desired coordinated formation flight, we present a novel distributed coordinated-control scheme comprising a consensus-based circling rendezvous, a coordinated path-following control for the leader UAVs, and a leader-follower coordinated control for the follower UAVs. The current framework embeds a formation pattern reconfiguration technique. Moreover, we discuss two security solutions(inter-UAV collision avoidance and obstacle avoidance) in the swarm flight problem. The effectiveness of the proposed coordinated control methods was demonstrated in field experiments by deploying up to 21 fixed-wing UAVs.

关键词： unmanned aerial vehicle cooperative control formation control distributed control multiagent system

Endocan-expressing microvessel density as a prognostic factor for survival in human gastric cancer

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World Journal of Gastroenterology 2016年第23期22卷 5422-5429页

作者： yuan chang Wei Niu Pei-long lian xian-qiang Wang Zhi-xin Meng Yi liu Rui Zhao Department of Anesthesiology Shandong Provincial Hospital Affiliated to Shandong University Department of Hepatobiliary Surgery Qilu HospitalShandong University Department of Pediatric surgery the PLA General Hospital

AIM: To investigate the expression of endocan in tumour vessels and the relationships between endocan and the expression of vascular endothelial growth factor(VEGF) and prognosis in gastric ***: This study included 142 patients with confirmed gastric cancer in a single cancer centre between 2008 and 2009. Clinicopathologic features were determined, and an immunohistochemical analysis of endocan-expressing microvessel density(MVD)(endocan-MVD), VEGF and vascular endothelial growth factor receptor 2(VEGFR2) was performed. Potential relationships between endocan-MVD and clinicopathological variables were assessed using a Student's t-test or an analysis of variance test. Spearman's rank correlation was applied to evaluate the relationship between endocan-MVD and the expression of VEGF/VEGFR2. long-term survival of these patients was analysed using univariate and multivariate ***: Positive staining of endocan was observed in most of the gastric cancer tissues(108/142) and in fewer of the normal gastric tissues. Endocan-MVD was not associated with gender or histological type(P > 0.05), while endocan-MVD was associated with tumour size,Borrmann type, tumour differentiation, tumour invasion, lymph node metastasis and TNM stage(P < 0.05). According to the Spearman's rank correlation analysis, endocan-MVD had a positive correlation with VEGF(r = 0.167, P = 0.047) and VEGFR2(r = 0.410, P = 0.000). The univariate analysis with a log-rank test indicated that the patients with a high level of endocan-MVD had a significantly poorer overall survival rate than those with a low level of endocan-MVD(17.9% vs 64.0%, P = 0.000). The multivariate analysis showed that a high level of endocan-MVD was a valuable prognostic ***: Endocan-MVD significantly correlates with the expression of VEGF and VEGFR2 and is a valuable prognostic factor for survival in human gastric cancer.

关键词： Endocan Microvessel density Vascular endothelial growth factor Gastric cancer Survival

Isolation,Sequence Analysis and Expression Profile of a Novel Swine Gene Differentially Expressed in the Longissimus Dorsi Muscle Tissues from LandracexLarge White Cross-combination

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Acta Biochimica et Biophysica Sinica 2005年第3期37卷 186-191页

作者： Yong-Gang LIU yuan-Zhu XIONG chang-Yan DENG Key Laboratory of Swine Genetics and Breeding.Ministry of Agriculture,Huazhong Agricultural University,Wuhan 430070.China Key Laboratory of Swine Genetics and Breeding Ministry of Agriculture Huazhong Agricultural UniversityWuhan 430070 China

The mRNA differential display technique was performed to investigate the differences in geneexpression in the Longissimus dorsi muscle tissues from LandracexLarge White *** gene that was differentially expressed was identified using semi-quantitative reverse transcriptase-polymerase chain reaction（RT-PCR）and its complete cDNA sequence was obtained using the rapid amplifi-cation of cDNA ends（RACE）*** nucleotide sequence of the gene is not homologous to any of theknown porcine *** sequence prediction analysis revealed that the open reading frame of this geneencodes a protein of 260 amino acids that contains the putative conserved domain of the carbonic anhydrase,and this protein has high homology with the carbonic anhydrase Ⅲ（CA-Ⅲ）of four species—mouse（91%）,horse（91%）,rat（89%）and human（86%）—so that it can be defined as swine carbonic anhydrase Ⅲ.Thephylogenetic tree analysis revealed that the swine CA-Ⅲ has a closer genetic relationship with the horse CA-Ⅲthan with those of mouse,rat and *** tissue expression analysis indicated that the swine CA-Ⅲ geneis generally expressed in most *** experiment is the first to establish the primary foundation forfurther research on the swine CA-Ⅲ gene.

关键词： mRNA differential display rapid amplification of cDNA ends(RACE) novel gene carbonic anhydrase Ⅲ(CA-Ⅲ)