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Effects of temperature and precipitation on drought trends in Xinjiang, China

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Journal of Arid Land 2024年第8期16卷 1098-1117页

作者： YANG Jianhua li yaqian ZHOU Lei ZHANG Zhenqing ZHOU Hongkui WU Jianjun Academy of Eco-civilization Development for Jing-Jin-Ji Megalopolis Tianjin Normal UniversityTianjin 300387China School of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijing 100044China Institute of Digital Agriculture Zhejiang Academy of Agricultural SciencesHangzhou 310021China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China

The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this *** this study,we first calculated the standard precipitation evapotranspiration index(SPEI)in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average *** the spatiotemporal characteristics of temperature,precipitation,and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil-Sen median trend analysis method and Mann-Kendall test.A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor(i.e.,temperature and precipitation).The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020,especially the spring temperature and winter *** to the influence of temperature,trends of intensifying drought have been observed at spring,summer,autumn,and annual *** addition,the drought trends in southern Xinjiang were more notable than those in northern *** 1980 to 2020,temperature trends exacerbated drought trends,but precipitation trends alleviated drought trends in *** meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter;in winter,most stations exhibited precipitation-dominated wetting *** findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought.

关键词： standardized precipitation evapotranspiration index(SPEI) climate change drought characteristics trend analysis arid area temperature trend contribution analysis

Pd^(0)-O v-Ce^(3+) Interfacial Sites with Charge Redistribution for Enhanced Hydrogenation of Methyl Oleate to Methyl Stearate

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Transactions of Tianjin University 2024年第4期30卷 359-368页

作者： Zhaohui Meng Ying liao ling liu yaqian li Hao Yan Xiang Feng Xiaobo Chen Yibin liu Chaohe Yang SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co. LtdDalianChina State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266580China

Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging *** our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)concentration in CeO_(2) through high-temperature *** process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl *** cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to *** interfacial sites exhibit a synergistic adsorption eff ect on the reaction ***^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating competition with C=C bonds for Pd^(0) adsorption *** synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated *** a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.

关键词： Hydrogenation Interfacial sites Oxygen vacancy C=C bond

2021年渤海浮游植物群落结构及其季节性变化

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海洋科学进展 2024年第2期42卷 337-348页

作者：李亚倩张倩杨世民中国海洋大学海洋生命学院山东青岛266003

为比较分析渤海中部和渤海海峡海域浮游植物群落结构的季节性变化及其与环境因子的相关性,分别于2021年春季、夏季和秋季在渤海(118°~122°E, 37°~40°N)设25个站位采集水样,开展浮游植物种类组成、细胞丰度空间分布、优势种、群落结... 详细信息

为比较分析渤海中部和渤海海峡海域浮游植物群落结构的季节性变化及其与环境因子的相关性,分别于2021年春季、夏季和秋季在渤海(118°~122°E, 37°~40°N)设25个站位采集水样,开展浮游植物种类组成、细胞丰度空间分布、优势种、群落结构和环境因子的综合调查研究。在研究海域共检出浮游植物3门68属168种,其中硅藻和甲藻在物种数和细胞丰度上占主要地位。研究结果显示,春季、夏季和秋季浮游植物水柱细胞丰度均值分别为78.76×10^(3)、18.83×10^(3)和25.02×10^(3)个/L,呈“双峰型”,春季为主高峰,秋季为次高峰。细胞丰度空间分布具有季节性差异,春季高值区位于渤海海峡,秋季高值区位于黄河入海口,夏季呈现斑块状分布。群落结构特征中的多样性指数、均匀度指数和丰富度指数均呈现秋季高于春季和夏季的趋势。渤海浮游植物群落结构的时空分布受多个环境因子共同控制,相较于夏季,春季和秋季营养盐对浮游植物的影响更为显著。

关键词：渤海浮游植物群落结构季节性变化

Study on the Effect of Multiple Strains of Metarhizium *** Fusarium verticillium

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Study on the Effect of Multiple Strains of Metarhizium *** F...

2000—2022年伊犁河流域植被时空变化特征

中国植物病理学会2024年学术年会

作者： WANG Yongkun HAN Yi CHEN Lusheng liU Jingyi WANG Caibo li yaqian CHEN Jie WANG Xinhua School of Agriculture and Biology Shanghai Jiao Tong University Institute of Agro-Environmental Microbial Engineering Shanghai Jiao Tong University Shanghai Minhang District Sannong Comprehensive Service Center

As a broad-spectrum entomogenous fungus,Metarhizium *** widely used to control the underground crop *** there are few studies on its control of soil-borne *** entomogenous fungi can prevent plant diseases has become one of the hotspots in the field of biological *** is one of the three major food crops in my *** verticillium is the main pathogen of root rot,stem rot and ear rot of *** this paper,eight biocontrol strains of Metarhizium spp.M1-M8 and Fusarium verticillium were selected for plate confrontation *** to the growth characteristics of Metarhizium spp.,Metarhizium *** first inoculated on the PDA plate for 6 days of culture,then Fusarium verticillium was inoculated to study the inhibitory effect of different species of Metarhizium *** Fusarium verticillium in *** test found that all of 8 Metarhizium *** could produce antibacterial zones against Fusarium *** which,M3(Metarhizium anisopliae) had the highest plate inhibition rate against Fusarium verticillium,reaching 57.2%,followed by the antibacterial rate of M2(Metarhizium anisopliae microsporum variant) was 44.44%,and the bacteriostatic rate of M5(Metarhizium anisopliae ***) was the lowest,only27.51%.The results show that some species of Metarhizium *** effectively inhibit the growth of pathogenic bacteria of soil-borne diseases,and have the dual effects of controlling underground pests and soil-borne pathogenic bacteria,and have good development and application prospects.

关键词： Metarhizium spp. maize Fusarium verticillium

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干旱区地理 2024年第5期47卷 741-752页

作者：李雅倩杨建华夏皓斌武建军天津师范大学京津冀生态文明发展研究院天津300387 北京师范大学地理科学学部北京100875

伊犁河流域横跨中哈两国,生态环境脆弱,深化对全流域植被变化的认识对于该地区生态可持续发展具有重要意义。基于MODIS的增强型植被指数(EVI)数据,深入研究了2000—2022年整个伊犁河流域植被的时空变化特征,并对比了中国境内外伊犁河流... 详细信息

伊犁河流域横跨中哈两国,生态环境脆弱,深化对全流域植被变化的认识对于该地区生态可持续发展具有重要意义。基于MODIS的增强型植被指数(EVI)数据,深入研究了2000—2022年整个伊犁河流域植被的时空变化特征,并对比了中国境内外伊犁河流域、不同植被类型、不同高程间植被变化的差异。结果表明:(1)2000年以来伊犁河流域植被总体呈现改善趋势,尤其是哈萨克斯坦境内的植被,然而中国境内植被有退化趋势。植被退化区域的高程集中在1000~3000 m之间;草地和耕地以改善为主,林地则相反。(2)过去20 a间,伊犁河流域植被总体波动较小,但中国境内流域植被的波动性较大。与林地和耕地相比,草地的波动性更大。高程在2500~3000 m区域内的植被波动小。(3)未来伊犁河流域植被状况以持续改善为主,持续改善面积约占全流域面积的52%。草地持续改善的面积占比高于耕地和林地。高程低于1000 m和高于3000 m区域的植被以持续改善为主。研究结果将有助于加深对伊犁河流域植被变化特征的理解,为流域生态环境保护提供科学参考。

关键词： MODIS EVI 变化趋势持续性伊犁河流域

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传统缠花云肩艺术表达与造物功能探析

武汉纺织大学学报 2024年第1期37卷 33-41页

作者：郭丽卓冬冬李亚倩武汉纺织大学服装学院湖北武汉430073

传统缠花云肩艺术表达与造物功能的探析对丰富云肩艺术研究和传承保护具有重要意义。文章以39件清代、民国缠花云肩为研究样本,借助文献、图像分析等研究方法,对传统缠花云肩的结构、纹样、色彩、工艺等方面进行归类、分析与总结,并从... 详细信息

传统缠花云肩艺术表达与造物功能的探析对丰富云肩艺术研究和传承保护具有重要意义。文章以39件清代、民国缠花云肩为研究样本,借助文献、图像分析等研究方法,对传统缠花云肩的结构、纹样、色彩、工艺等方面进行归类、分析与总结,并从历史渊源和民间藏品进行考证,探究其艺术表达和造物功能。研究认为:第一,缠花源于簪花习俗,盛行的宋代,而传统缠花云肩作为缠花诸多品类的一种,与缠花发展演变密切相关。第二,传统缠花云肩艺术特色鲜明,其结构形制种类多样、设计巧妙灵动;纹样以单个和多个组合形式较为常见,寓意吉祥;置色多而大胆,视觉语言丰富,具有雅俗互鉴的特点;工艺制作为“以缠代缘”和“缠作绣、布为底”两种方式进行。第三,受传统造物思想影响,此类云肩具有“增视”“调和”“添彩”和“掩暇”的造物功能。

关键词：缠花工艺缠花云肩缘饰艺术表达造物功能

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传统葫芦纹在服饰品设计中的应用探析

武汉纺织大学学报 2024年第3期37卷 47-54页

作者：李亚倩卓冬冬郭丽武汉纺织大学服装学院湖北武汉430073

葫芦纹作为中国历史最为悠久的纹样之一,具有着丰富的文化内涵与吉祥寓意,将其应用于现代服饰品设计中,不仅是对中国传统文化的传承与活化,同时也为现代设计开创新的思路。文章运用了文献查阅、图像分析、设计实践等研究方法,分析传统... 详细信息

葫芦纹作为中国历史最为悠久的纹样之一,具有着丰富的文化内涵与吉祥寓意,将其应用于现代服饰品设计中,不仅是对中国传统文化的传承与活化,同时也为现代设计开创新的思路。文章运用了文献查阅、图像分析、设计实践等研究方法,分析传统葫芦纹在现代服饰品中的多样化呈现方式,总结葫芦纹在服饰品中的应用原则,设计出创新纹样,并进行实践应用,最终得出传统葫芦纹在现代服饰品中的应用效果。研究认为:首先,传统葫芦纹在服饰品中多样化的设计表现,与现代服饰品有较强的适配性,符合现代服饰品的多元化发展潮流,满足当代人们追求个性化、艺术化的心理需求。其次,传统葫芦纹在服饰品中的设计应遵循三个应用原则,1)遵循适用原则,注重葫芦纹产品的实用性及人性化功能;2)符合审美需求,丰富葫芦纹在服饰品设计中的时尚元素;3)注重文化传承,传递葫芦纹的吉祥文化寓意。最后,利用现代的设计手段,从传统葫芦纹荷包、发簪、耳饰中手绘提取葫芦纹的图像特征,采取主题式纹样设计和组合式纹样设计方法,结合现代的设计元素进行再设计,使得葫芦纹相较于原纹样更具时尚感与趣味性,并将其实现于包袋、项链、耳饰中,使产品以新颖的方式融入现代生活。

关键词：葫芦纹传统纹样服饰品设计设计应用

豆渣基掺氮碳量子点的制备及对水中对硝基苯酚的光学检测

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农业环境科学学报 2024年第4期43卷 955-962页

作者：杨钰钰卫潇李雅倩刘欣妮王凤杰何红珠高月长安大学水利与环境学院西安710054 旱区地下水文与生态效应教育部重点实验室西安710054 水利部旱区生态水文与水安全重点实验室西安710054

为利用废弃豆渣,开发废弃生物质能源的有效利用方式,实现“以废治废”,本研究以水为溶剂、以富氮废弃豆渣为碳源和氮源,采用一步水热法合成豆渣基氮掺杂的碳量子点(N-CQDs),进而基于N-CQDs构建了一种用于水环境中痕量对硝基苯酚(PNP)的... 详细信息

为利用废弃豆渣,开发废弃生物质能源的有效利用方式,实现“以废治废”,本研究以水为溶剂、以富氮废弃豆渣为碳源和氮源,采用一步水热法合成豆渣基氮掺杂的碳量子点(N-CQDs),进而基于N-CQDs构建了一种用于水环境中痕量对硝基苯酚(PNP)的快速高效检测新方法。N-CQDs制备过程绿色、简单,同时采用自身供氮、供碳的豆渣制备碳量子点实现了对废弃生物质能源的开发和再利用。通过透射电镜、红外光谱、紫外-可见吸收光谱、荧光光谱等表征了N-CQDs的形貌和光学特征;并探究了N-CQDs荧光传感器对PNP的最佳检测条件和检测性能。在最佳检测条件下,N-CQDs的荧光猝灭程度与PNP的浓度呈良好线性关系。此外,通过图谱重叠分析、荧光寿命衰减曲线测定与解析以及双指数模型拟合,揭示了其检测机理为内滤效应。该传感器已成功应用于自来水样品中的PNP定量检测,且具有良好抗干扰能力,为废弃豆渣再利用提供了一种思路。

关键词：碳量子点对硝基苯酚豆渣荧光检测

维普期刊数据库博看期刊

Fast algorithm for viscous Cahn-Hilliard equation

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Frontiers of Mathematics in China 2022年第4期17卷 689-713页

作者： Danxia WANG yaqian li Xingxing WANG Hongen JIA College of Mathematics Taiyuan University of TechnologyTaiyuan030024China

The main purpose of this paper is to solve the viscous Cahn-Hilliard equation via a fast algorithm based on the two time-mesh(TT-M)finite element(FE)method to ease the problem caused by strong *** TT-M FE algorithm includes the following main computing ***,a nonlinear FE method is applied on a coarse time-meshτ_(c).Here,the FE method is used for spatial discretization and the implicit second-orderθscheme(containing both implicit Crank-Nicolson and second-order backward difference)is used for temporal ***,based on the chosen initial iterative value,a linearized FE system on time fine mesh is solved,where some useful coarse numerical solutions are found by Lagrange’s interpolation *** analysis for both stability and a priori error estimates is made in *** examples are given to demonstrate the validity of the proposed *** algorithm is compared with the traditional Galerkin FE method and it is evident that our fast algorithm can save computational time.

关键词： Fast algorithm two time-mesh(TT-M)finite element(FE)method viscous Cahn-Hilliard equation stability CPU time