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Digital Construction of Rural Landscape Based on DEM:A Case Study of Xiangyu Village of West Beijing 被引量:1
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作者 Yufan LIU jin zhang 《Meteorological and Environmental Research》 CAS 2023年第3期63-68,共6页
[Objective]The paper uses Geographic Information System(ArcGIS)as a platform to discuss the study of DEM data on the digital construction of rural landscape databases and the coupling relationship in geographic space ... [Objective]The paper uses Geographic Information System(ArcGIS)as a platform to discuss the study of DEM data on the digital construction of rural landscape databases and the coupling relationship in geographic space of rural landscape.The aim is to further expand the coverage of China's land space digitization and provide practical theoretical basis and development possibility of quantitative planning for village level administrative zoning research.[Method]In this paper,Xiangyu Village,Junzhuang Town,Mentougou,West Beijing,is selected as the research object,and the document space database of the study area is constructed by building digital elevation model(DEM),ArcGIS stacked map weighting and visual interpretation methods.Moreover,its elevation equivalence,slope direction,and water flow direction are visually analyzed.[Result]The mountainous terrain and hydrological characteristics of Xiangyu Village are roughly consistent with the village layout;the living environment of Xiangyu Village is consistent with the terrain and texture,and it belongs to the rural landscape system of mountains,valleys and small watersheds.[Conclusion]The results obtained through data visualization analysis are basically consistent with the traditional village planning pattern of Xiangyu Village;the rural landscape based on village level administrative divisions is still in the traditional planning stage,and there is great development space for village level geographic spatial survey.Therefore,it is necessary for relevant practitioners to make more contributions to fill the full coverage of China's land space digitization. 展开更多
关键词 DEM Rural landscape DIGITIZATION Xiangyu Village GIS
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一锅法光热催化升级转化聚乳酸制备氢气和丙酮酸
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作者 向媛 张进 +6 位作者 黄飞 肖楠天 范怡怡 张俊豪 郑珩 陈金伟 张帆 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第4期149-158,共10页
聚乳酸(PLA)是一种生物可降解高分子材料,近年来已广泛用作常规塑料的替代品.然而,其在自然环境中生物降解往往需要较长时间,这不仅延长了降解周期,还导致了碳资源的浪费.光热催化技术不仅可以利用清洁的太阳能资源原位产生活性氧化还... 聚乳酸(PLA)是一种生物可降解高分子材料,近年来已广泛用作常规塑料的替代品.然而,其在自然环境中生物降解往往需要较长时间,这不仅延长了降解周期,还导致了碳资源的浪费.光热催化技术不仅可以利用清洁的太阳能资源原位产生活性氧化还原物种,同时通过引入热源改善纯光或纯热催化效率低和产物选择性差等难题,有望在塑料催化升级转化过程中发挥作用.本文通过原位光沉积方法分别在二氧化钛(TiO_(2))、氮化碳纳米片(A-V-PCN)和硫化镉(CdS)半导体载体上制备了一系列铂基光热催化剂,铂纳米粒子的平均粒径约2 nm.对铂基光热催化剂的光热催化乳酸水溶液的析氢反应进行了综合评价和比较.结果表明,铂基光热催化剂的光热催化制氢性能远优于纯光催化和纯热催化.其中,CdS半导体负载的铂基催化剂(Pt/CdS)对聚乳酸光热催化转化表现出最优的催化活性,在150°C时,Pt/CdS催化产氢速率分别是Pt/TiO_(2)和Pt/A-V-PCN的1.2倍和4.8倍.变温光电流密度响应、莫特-肖特基以及荧光光谱测试结果表明,提高温度可以有效地抑制光生载流子的复合,从而大幅度提高光热催化转化效率.对不同光热催化剂的液相产物和能带结构进行分析发现,具有合适带隙的CdS半导体能够高选择性地催化生成丙酮酸.相比之下,TiO_(2)和A-V-PCN半导体上由于形成羟基自由基,导致丙酮酸被进一步氧化分解为乙醛和少量的甲酸.原位电子自旋共振表征和理论计算结果进一步揭示,CdS有助于关键中间体(碳中心自由基)的形成和连续脱氢,从而促进了Pt/CdS高选择性制备丙酮酸,并有效抑制过氧化产物的累积.将Pt/CdS催化剂应用于实际聚乳酸塑料时,其光热催化反应的制氢速率为200±17.5 mmol·gcat^(-1)·gplastic^(-1),丙酮酸在液体产物中的选择性为98.1%,产率达到100±11.5 mmol·gcat^(-1)·gplastic^(-1).循环稳定性实验和反应前后的催化剂表征结果表明,Pt/CdS催化剂在光热反应条件下具有较好的稳定性.综上,本工作实现了一锅法光热催化转化聚乳酸为氢气和高附加值含氧化合物丙酮酸,发展了一种高效高选择性转化塑料废弃物为高附加值化学品的光热催化策略,为废塑料碳资源的绿色循环利用提供了解决思路. 展开更多
关键词 塑料升级回收 光热催化 制氢 聚乳酸 丙酮酸
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甜瓜HDM基因家族鉴定及特性分析
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作者 张治 张婧 +2 位作者 张瑾 哈斯阿古拉 郝金凤 《遗传》 CAS CSCD 北大核心 2024年第2期168-180,共13页
组蛋白去甲基化酶(histone demethylase,HDM)是生物生长过程中的重要调节因子之一,在植物的生长发育和环境适应过程中发挥着重要的调控作用。本研究通过生物信息学方法对甜瓜(Cucumis melo L.) HDM基因家族进行了鉴定,并通过转录组数据... 组蛋白去甲基化酶(histone demethylase,HDM)是生物生长过程中的重要调节因子之一,在植物的生长发育和环境适应过程中发挥着重要的调控作用。本研究通过生物信息学方法对甜瓜(Cucumis melo L.) HDM基因家族进行了鉴定,并通过转录组数据检测了其成员在甜瓜组织的表达特性。结果显示,在甜瓜基因组中鉴定得到了20个CmHDM基因,在各条染色体上非均匀分布;其成员可以分成LSD1和JmjC两大类,而JmjC类群又可划分为5个亚群,各类群成员数量不等;种内和种间的共线性关系显示,甜瓜HDM基因仅存在一对片段重复,与番茄(Solanum lycopersicum) HDM基因共线性区域较多,亲缘关系较近;各成员所含保守结构域数量不等,且外显子和内含子在数量上有所差异;在启动子区域存在多种与激素和环境信号响应的顺式作用元件,表达特性分析显示各基因成员在甜瓜雄花、雌花、根、茎、叶、子房和成熟果实中均存在不同程度的表达。这些结果将有助于更好地理解HDM基因的潜在功能以及它们在参与调节甜瓜生长发育和环境自适中可能发挥的作用。 展开更多
关键词 甜瓜 HDM家族 基因鉴定 表达分析
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Chemico-biological conversion of carbon dioxide 被引量:1
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作者 Liangwei Hu Junzhu Yang +3 位作者 Qi Xia jin zhang Hongxin Zhao Yuan Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期371-387,I0009,共18页
The unabated carbon dioxide(CO_(2))emission into the atmosphere has exacerbated global climate change,resulting in extreme weather events,biodiversity loss,and an intensified greenhouse effect.To address these challen... The unabated carbon dioxide(CO_(2))emission into the atmosphere has exacerbated global climate change,resulting in extreme weather events,biodiversity loss,and an intensified greenhouse effect.To address these challenges and work toward carbon(C)neutrality and reduced CO_(2)emissions,the capture and utilization of CO_(2)have become imperative in both scientific research and industry.One cutting-edge approach to achieving efficient catalytic performance involves integrating green bioconversion and chemical conversion.This innovative strategy offers several advantages,including environmental friendliness,high efficiency,and multi-selectivity.This study provides a comprehensive review of existing technical routes for carbon sequestration(CS)and introduces two novel CS pathways:the electrochemicalbiological hybrid and artificial photosynthesis systems.It also thoroughly examines the synthesis of valuable Cnproducts from the two CS systems employing different catalysts and biocatalysts.As both systems heavily rely on electron transfer,direct and mediated electron transfer has been discussed and summarized in detail.Additionally,this study explores the conditions suitable for different catalysts and assesses the strengths and weaknesses of biocatalysts.We also explored the biocompatibility of the electrode materials and developed novel materials.These materials were specifically engineered to combine with enzymes or microbial cells to solve the biocompatibility problem,while improving the electron transfer efficiency of both.Furthermore,this review summarizes the relevant systems developed in recent years for manufacturing different products,along with their respective production efficiencies,providing a solid database for development in this direction.The novel chemical-biological combination proposed herein holds great promise for the future conversion of CO_(2)into advanced organic compounds.Additionally,it offers exciting prospects for utilizing CO_(2)in synthesizing a wide range of industrial products.Ultimately,the present study provides a unique perspective for achieving the vital goals of“peak shaving”and C-neutrality,contributing significantly to our collective efforts to combat climate change and its associated challenges. 展开更多
关键词 Carbon dioxide Bioelectric synthesis Artificial photosynthesis Synthetic product
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Au NPs/Cu-TCPP材料的构筑及其催化薄荷醇氧化的研究
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作者 李世叶 张剑 +3 位作者 王杰 杨超 张晋 成世兴 《日用化学工业(中英文)》 CAS 北大核心 2024年第11期1330-1338,共9页
二维纳米片具有大的比表面积和高孔隙率的特征,这使得其可以承载更多的活性中心,从而提高该材料的催化性能。如Cu-TCPP纳米片,拥有大的比表面积,可用于负载Pd NPs、Pt NPs以及Au NPs,以获得X NPs/Cu-TCPP纳米片(X=Pd NPs、Pt NPs和Au N... 二维纳米片具有大的比表面积和高孔隙率的特征,这使得其可以承载更多的活性中心,从而提高该材料的催化性能。如Cu-TCPP纳米片,拥有大的比表面积,可用于负载Pd NPs、Pt NPs以及Au NPs,以获得X NPs/Cu-TCPP纳米片(X=Pd NPs、Pt NPs和Au NPs)。本研究首先通过水热法,以三水合硝酸铜(Cu(NO_(3))_(2)·3H_(2)O)为金属盐,4-羧基卟啉(TCPP)为有机配体,N,N-二甲基甲酰胺(DMF)和CH_(3)CH_(2)OH(体积比3∶1)的混合溶液作为溶剂,合成Cu-TCPP纳米片。随后,采用还原法将Au NPs负载到Cu-TCPP纳米片上,形成Au NPs/Cu-TCPP纳米片,用于催化薄荷醇进行选择性氧化反应。在反应中,以叔丁基过氧化氢(TBHP)为氧化剂,乙腈(Me CN)为溶剂,氨基酸咪唑离子液体([C_(4)mim]Cys)为助催化剂,Au NPs/Cu-TCPP催化薄荷醇进行选择性氧化,生成薄荷酮。在50℃下反应18 h,薄荷醇的转化率和薄荷酮的选择性和产率都达到最高,分别为70.2%,99.9%和69.5%,该方法不仅将薄荷醇转化为高选择性的薄荷酮,而且操作简便,绿色环保,符合当前绿色化工发展的要求。 展开更多
关键词 二维纳米片 Au NPs/Cu-TCPP纳米片 薄荷醇 选择性氧化 薄荷酮
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Expression analysis of the R2R3-MYB gene family in upland cotton and functional study of GhMYB3D5 in regulating Verticillium wilt resistance
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作者 Jie Liu Zhicheng Wang +15 位作者 Bin Chen Guoning Wang Huifeng Ke jin zhang Mengjia Jiao Yan Wang Meixia Xie Yanbin Li Dongmei zhang Xingyi Wang Qishen Gu Zhengwen Sun Liqiang Wu Xingfen Wang Zhiying Ma Yan zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3294-3310,共17页
Improving plant resistance to Verticillium wilt(VW),which causes massive losses in Gossypium hirsutum,is a global challenge.Crop plants need to efficiently allocate their limited energy resources to maintain a balance... Improving plant resistance to Verticillium wilt(VW),which causes massive losses in Gossypium hirsutum,is a global challenge.Crop plants need to efficiently allocate their limited energy resources to maintain a balance between growth and defense.However,few transcriptional regulators specifically respond to Verticillium dahliae and the underlying mechanism has not been identified in cotton.In this study,we found that the that expression of most R2R3-MYB members in cotton is significantly changed by V.dahliae infection relative to the other MYB types.One novel R2R3-MYB transcription factor(TF)that specifically responds to V.dahliae,GhMYB3D5,was identified.GhMYB3D5 was not expressed in 15 cotton tissues under normal conditions,but it was dramatically induced by V.dahliae stress.We functionally characterized its positive role and underlying mechanism in VW resistance.Upon V.dahliae infection,the up-regulated GhMYB3D5 bound to the GhADH1 promoter and activated GhADH1expression.In addition,GhMYB3D5 physically interacted with GhADH1 and further enhanced the transcriptional activation of GhADH1.Consequently,the transcriptional regulatory module GhMYB3D5-GhADH1 then promoted lignin accumulation by improving the transcriptional levels of genes related to lignin biosynthesis(GhPAL,GhC4H,Gh4CL,and GhPOD/GhLAC)in cotton,thereby enhancing cotton VW resistance.Our results demonstrated that the GhMYB3D5 promotes defense-induced lignin accumulation,which can be regarded as an effective way to orchestrate plant immunity and growth. 展开更多
关键词 COTTON Verticillium wilt resistance GhMYB3D5 GhADH1 transcriptional regulatory module
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THE SUPERCLOSENESS OF THE FINITE ELEMENT METHOD FOR A SINGULARLY PERTURBED CONVECTION-DIFFUSION PROBLEM ON A BAKHVALOV-TYPE MESH IN 2D
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作者 Chunxiao zhang jin zhang 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1572-1593,共22页
For singularly perturbed convection-diffusion problems,supercloseness analysis of the finite element method is still open on Bakhvalov-type meshes,especially in the case of 2D.The difficulties arise from the width of ... For singularly perturbed convection-diffusion problems,supercloseness analysis of the finite element method is still open on Bakhvalov-type meshes,especially in the case of 2D.The difficulties arise from the width of the mesh in the layer adjacent to the transition point,resulting in a suboptimal estimate for convergence.Existing analysis techniques cannot handle these difficulties well.To fill this gap,here a novel interpolation is designed delicately for the smooth part of the solution,bringing about the optimal supercloseness result of almost order 2 under an energy norm for the finite element method.Our theoretical result is uniform in the singular perturbation parameterεand is supported by the numerical experiments. 展开更多
关键词 singularly perturbed CONVECTION-DIFFUSION finite element method SUPERCLOSENESS Bakhvalov-type mesh
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数字化的碳排放效应:文献述评与研究展望
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作者 张瑾 史丹 +1 位作者 董战峰 李金铠 《经济管理学刊》 2024年第3期31-56,共26页
当前,以数字技术创新与应用为特征的数字化日益成为降低碳排放和推进经济社会发展全面绿色转型的重要手段与工具。但是,数字化是否必然促进碳减排尚无共识,相关研究仍处于探索阶段,缺乏理论阐述,实证结果不一。为厘清数字化与碳排放的... 当前,以数字技术创新与应用为特征的数字化日益成为降低碳排放和推进经济社会发展全面绿色转型的重要手段与工具。但是,数字化是否必然促进碳减排尚无共识,相关研究仍处于探索阶段,缺乏理论阐述,实证结果不一。为厘清数字化与碳排放的复杂关系,探究数字化的碳排放效应,本文对国内外相关研究进行系统梳理和评述。首先,基于理论溯源与演进,对数字化与碳排放关系的理论阐释进行系统归纳,总结提出了三层次、三阶段、四阶段、系统嵌套等多维理论分析框架,为相关研究奠定了学理基础;其次,归纳总结了数字化影响碳排放的四种机理,为探究数字化与碳排放的关系提供了分析思路;再次,梳理和综述了当前关于数字化碳排放效应的实证进展;最后,在前述基础上提出了未来研究的方向。 展开更多
关键词 数字化 低碳化 碳减排
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Bifunctional passivation by lewis-base molecules for efficient printable mesoscopic perovskite solar cells
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作者 Hang Yang Jianhong Zhao +8 位作者 Xiaodong Ren Tong Zhou Henbing zhang Weilong zhang jin zhang Guangzhi Hu Yuming zhang Wen-Hua zhang Qingju Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期177-184,共8页
Printable mesoscopic perovskite solar cells(PM-PSCs)possess notable merits in terms of cost-effectiveness,easy manufacturing,and large scale applications.Nevertheless,the absence of a hole transport layer contributes ... Printable mesoscopic perovskite solar cells(PM-PSCs)possess notable merits in terms of cost-effectiveness,easy manufacturing,and large scale applications.Nevertheless,the absence of a hole transport layer contributes to the exacerbation of carrier recombination,and the defects between the perovskite and electron transport layer(ETL)interfaces significantly decrease the efficiency of the devices.In this study,a bifunctional surface passivation approach is proposed by applying a thioacetamide(TAA)surfactant on the mesoporous TiO_(2)interface.The results demonstrate that TAA molecules could interact with TiO_(2),thereby diminishing the oxygen vacancy defects.Additionally,the amino group and sulfur atoms in TAA molecules act as Lewis base to effectively passivate the uncoordinated Pb^(2+)in perovskite and improve the morphology of perovskite,and decrease the trap-state density of perovskite.The TAA passivation mechanism improves the alignment of energy levels between TiO_(2)and perovskite,facilitating electron transport and reducing carrier recombination.Consequently,the TAA-passivated device achieved a champion power conversion efficiency(PCE)of 17.86%with a high fill factor(FF)of 79.16%and an open-circuit voltage(V_(OC))of 0.971 V.This investigation presents a feasible strategy for interfacial passivation of the ETL to further improve the efficiency of PM-PSCs. 展开更多
关键词 Perovskite solarcells Carbon electrode THIOACETAMIDE Interfacial passivation
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Surface repair of wide-bandgap perovskites for high-performance all-perovskite tandem solar cells
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作者 Xiaojing Lv Weisheng Li +11 位作者 jin zhang Yujie Yang Xuefei Jia Yitong Ji Qianqian Lin Wenchao Huang Tongle Bu Zhiwei Ren Canglang Yao Fuzhi Huang Yi-Bing Cheng jinhui Tong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期64-70,I0003,共8页
Wide-bandgap(WBG)perovskite solar cells(PSCs)play a fundamental role in perovskite-based tandem solar cells.However,the efficiency of WBG PSCs is limited by significant open-circuit voltage losses,which are primarily ... Wide-bandgap(WBG)perovskite solar cells(PSCs)play a fundamental role in perovskite-based tandem solar cells.However,the efficiency of WBG PSCs is limited by significant open-circuit voltage losses,which are primarily caused by surface defects.In this study,we present a novel method for modifying surfaces using the multifunctional S-ethylisothiourea hydrobromide(SEBr),which can passivate both Pb^(-1)and FA^(-1)terminated surfaces,Moreover,the SEBr upshifted the Fermi level at the perovskite interface,thereby promoting carrier collection.This proposed method was effective for both 1.67 and 1.77 eV WBG PSCs,achieving power conversion efficiencies(PCEs)of 22.47%and 19.90%,respectively,with V_(OC)values of 1.28 and 1.33 V,along with improved film and device stability.With this advancement,we were able to fabricate monolithic all-perovskite tandem solar cells with a champion PCE of 27.10%,This research offers valuable insights for passivating the surface trap states of WBG perovskite through rational multifunctional molecular engineering. 展开更多
关键词 Wide-bandgap perovskite Surface defect Multifunctional molecule All-perovskite tandem solar cells
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The glutamate receptor gene GLR3.3:A bridge of calciummediated root development in poplar
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作者 Yi An Ya Geng +5 位作者 Yu Liu Xiao Han Lichao Huang Wei Zeng jin zhang Mengzhu Lu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第6期1449-1462,共14页
Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Cal... Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Calcium(Ca),as a signaling molecule,is involved in the regulation of plant root development.However,the detailed underlying regulatory mechanism is elusive.In this study,we analyzed the morphological and transcriptomic variations of 84K poplar(Populus alba×P.glandulosa)in response to different calcium concentrations and found that low Ca^(2+)(1 mmol·L^(-1))promoted lateral root development,while deficiency(0.1 mmol·L^(-1)Ca^(2+))inhibited lateral root development.Co-expression analysis showed that Ca^(2+)channel glutamate receptors(GLRs)were present in various modules with significance for root development.Two GLR paralogous genes,PagGLR3.3a and Pag GLR3.3b,were mainly expressed in roots and up-regulated under Ca^(2+)deficiency.The CRISPR/Cas9-mediated signal gene(crispr-PagGLR3.3a,PagGLR3.3b)and double gene(crispr-PagGLR3.3ab)mutants presented more and longer lateral roots.Anatomical analysis showed that crispr-PagGLR3.3ab plants had more xylem cells and promoted the development of secondary vascular tissues.Further transcriptomic analysis suggested that knockout of PagGLR3.3a and PagGLR3.3b led to the up-regulation of several genes related to protein phosphorylation,auxin efflux,lignin and hemicellulose biosynthesis as well as transcriptional regulation,which might contribute to lateral root growth.This study not only provides novel insight into how the Ca^(2+)channels mediated root growth and development in trees,but also provides a directive breeding of new poplar species for biofuel and bioenergy production. 展开更多
关键词 Glutamate receptor CALCIUM Root development Lateral root POPLAR
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Lobe-dominatedγ-Ray Emission of Compact Symmetric Objects
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作者 Ying-Ying Gan Hai-Ming zhang +2 位作者 Xing Yang Ying Gu jin zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期196-205,共10页
Theγ-ray emitting compact symmetric objects(CSOs)PKS 1718-649,NGC 3894,and TXS 0128+554 are lobedominated in the radio emission.In order to investigate theirγ-ray radiation properties,we analyze the~14yr Fermi/LAT o... Theγ-ray emitting compact symmetric objects(CSOs)PKS 1718-649,NGC 3894,and TXS 0128+554 are lobedominated in the radio emission.In order to investigate theirγ-ray radiation properties,we analyze the~14yr Fermi/LAT observation data of the three CSOs.They all show the low luminosity(1041-1043 erg s-1)and no significant variability in theγ-ray band.Theirγ-ray average spectra can be well fitted by a power-law function.These properties ofγ-rays are clearly different from theγ-ray emitting CSOs CTD 135 and PKS 1413+135,for which theγ-rays are produced by a restarted aligned jet.In the L_(γ)-Γ_(γ)plane,the three CSOs are also located at the region occupied by radio galaxies(RGs)while CTD 135 and PKS 1413+135 display a similar feature to blazars.Together with a similar radio emission property toγ-ray emitting RGs Cen A and Fornax A,we speculate that theγ-rays of the three CSOs stem from their extended mini-lobes.The broadband spectral energy distributions of the three CSOs can be well explained by the two-zone leptonic model,where theirγ-rays are produced by the inverse Compton process of the relativistic electrons in extended regions.By extrapolating the observed Fermi/LAT spectra to the very high energy band,we find that TXS 0128+554 among the three CSOs may be detected by the Cherenkov Telescope Array in the future. 展开更多
关键词 GALAXIES active-galaxies jets-radio continuum galaxies-gamma-rays GALAXIES
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基于蜡酯型乳化剂的液晶结构乳状液的制备研究及应用性能表征
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作者 沈玲华 Vincent Hubiche +4 位作者 Paua Lennon 庄洁 张瑾 张倩洁 张婉萍 《日用化学工业(中英文)》 CAS 北大核心 2024年第11期1320-1329,共10页
研究了制备工艺和配方组成(油脂、多元醇、流变调节剂和离子性成分)对蜡酯型乳化剂液晶结构形成的影响,并对其液晶结构乳状液进行了相关的应用性能测试。实验结果表明,一罐法制备乳液更有利于该乳化剂配方体系液晶结构的形成。该乳化剂... 研究了制备工艺和配方组成(油脂、多元醇、流变调节剂和离子性成分)对蜡酯型乳化剂液晶结构形成的影响,并对其液晶结构乳状液进行了相关的应用性能测试。实验结果表明,一罐法制备乳液更有利于该乳化剂配方体系液晶结构的形成。该乳化剂与植物油脂相溶性较好,乳化能力较佳,对于植物来源酯类油脂,遵循油水界面张力越小,乳化效果越佳,越有利于液晶结构形成的规律;甘油的添加能使体系保持最初优异的液晶结构及其稳定性,但1,3-丁二醇会由于其氢键与水形成的水合基团扰乱界面膜分子排列,从而使体系的液晶结构完整性及稳定性有所降低;离子性成分的添加可通过增加乳化剂紧密排列来明显增强体系的液晶结构;天然流变调节剂的加入,如AX和Tara,可以增强体系液晶结构的高温稳定性,而卡波类可增强其低温稳定性。同时,通过对液晶结构乳状液应用性能的研究发现,使用蜡酯型乳化剂制备得到的液晶结构乳状液保湿性能明显优于普通结构乳状液,且具有一定的缓释作用。 展开更多
关键词 液晶结构 蜡酯型乳化剂 制备工艺 配方组成 使用性能
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Effect of intraoperative injection of esketamine on postoperative analgesia and postoperative rehabilitation after cesarean section
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作者 Hong-Zhuan Chen Yi Gao +4 位作者 Ke-Ke Li Li An jing Yan Hong Li jin zhang 《World Journal of Clinical Cases》 SCIE 2024年第28期6195-6203,共9页
BACKGROUND Following cesarean section,a significant number of women encounter moderate to severe pain.Inadequate management of acute pain post-cesarean section can have far-reaching implications,adversely impacting ma... BACKGROUND Following cesarean section,a significant number of women encounter moderate to severe pain.Inadequate management of acute pain post-cesarean section can have far-reaching implications,adversely impacting maternal emotional wellbeing,daily activities,breastfeeding,and neonatal care.It may also impede maternal organ function recovery,leading to escalated opioid usage,heightened risk of postpartum depression,and the development of chronic postoperative pain.Both the Chinese Enhanced Recovery After Surgery(ERAS)guidelines and the American ERAS Society guidelines consistently advocate for the adoption of multimodal analgesia protocols in post-cesarean section pain management.Esketamine,functioning as an antagonist of the N-Methyl-D-Aspartate receptor,has been validated for pain management in surgical patients and has exhibited effectiveness in depression treatment.Research has suggested that incorporating esketamine into postoperative pain management via pain pumps can lead to improvements in short-term depression and pain outcomes.This study aims to assess the efficacy and safety of administering a single dose of esketamine during cesarean section.AIM To investigate the effect of intraoperative injection of esketamine on postoperative analgesia and postoperative rehabilitation after cesarean section.METHODS A total of 315 women undergoing elective cesarean section under combined spinal-epidural anesthesia were randomized into three groups:low-dose esketamine(0.15 mg/kg),high-dose esketamine(0.25 mg/kg),and control(saline).Postoperative Visual Analog Scale(VAS)scores were recorded at 6 hours,12 hours,24 hours,and 48 hours.Edinburgh Postnatal Depression Scale(EPDS)scores were noted on 2 days,7 days and 42 days.Ramsay sedation scores were assessed at specified intervals post-injection.Postoperative adverse reactions were also recorded.RESULTS Low-dose group and high-dose group compared to control group,had significantly lower postoperative VAS pain scores at 6 hours 12 hours,and 24 hours(P<0.05),with reduced analgesic usage(P<0.05).EPDS scores and postpartum depression rates were significantly lower on 2 days and 7 days(P<0.05).No significant differences in first exhaust and defecation times were observed(P>0.05),but ambulation times were shorter(P<0.05).Ramsay scores were higher at 5 minutes,15 minutes,and upon room exit(P<0.05).Low-dose group and high-dose group had higher incidences of hallucination,lethargy,and diplopia within 2 hours(P<0.05),and with low-dose group had lower incidences of hallucination,lethargy,and diplopia than high-dose group(P<0.05).CONCLUSION Esketamine enhances analgesia and postpartum recovery;a 0.15 mg/kg dose is optimal for cesarean sections,balancing efficacy with minimized adverse effects. 展开更多
关键词 MATERNITY Cesarean section DEPRESSION Esketamine Postoperative analgesia
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地域文化视域下浙江高校校园设计特色研究
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作者 章瑾 司舵 黄张媛 《工程设计与施工》 2024年第7期170-172,共3页
论文通过梳理浙江现有的高校校园规划发展脉络及建筑特色,总结浙江地域文化条件下的当代高校校园规划与建筑设计的特点及其成因,并与同时期国内外优秀的校园设计进行对比,挖掘现有设计背后的不足和劣势,为高校校园规划设计寻求更适宜的... 论文通过梳理浙江现有的高校校园规划发展脉络及建筑特色,总结浙江地域文化条件下的当代高校校园规划与建筑设计的特点及其成因,并与同时期国内外优秀的校园设计进行对比,挖掘现有设计背后的不足和劣势,为高校校园规划设计寻求更适宜的设计策略,并且提供正确的方向和思路。通过高校校园规划设计中的“地域性”表达,以及高校探索城市历史文化基因传承等方面的研究,希望能为高校校园规划设计提供一些新的思路和借鉴,推动校园设计的创新与发展。 展开更多
关键词 地域文化 高校 设计特色 传承 发展
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Exploring the anti-osteoporotic potential of simvastatin and metformin: a comprehensive Mendelian randomization and animal experiment investigation
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作者 Hui Zhou jin zhang +3 位作者 Pei-Pei He Yu Gou Xun Sun He-Tong Li 《Biomedical Engineering Communications》 2024年第4期29-38,共10页
Background:Both simvastatin and metformin have demonstrated potential efficacy in osteoporosis(OP)treatment.However,there is a lack of systematic studies comparing their anti-osteoporotic effects.This study aims to co... Background:Both simvastatin and metformin have demonstrated potential efficacy in osteoporosis(OP)treatment.However,there is a lack of systematic studies comparing their anti-osteoporotic effects.This study aims to compare the effects of simvastatin and metformin on OP through Mendelian randomization(MR)studies and animal experiments.Methods:Initially,we will analyze the causal impact of simvastatin or metformin treatment on OP prevalence and three common clinical OP diagnostic markers(bone mineral density(BMD),serum osteocalcin(OCN),and tartrate-resistant acid phosphatase(TRAP)levels)using genome-wide association study(GWAS)summary statistics.Additionally,we established animal models to further analyze and compare the anti-osteoporosis effects of simvastatin and metformin.8 male C57BL/6J mice(3-month-old)and 24 male C57BL/6J mice(18-month-old)were treated with simvastatin or metformin for 12 weeks.OP pathology was assessed using histology,immunohistochemistry,biomechanical tests,micro-computed tomography,and osteogenic differentiation assays.Results:In the MR analysis,metformin treatment was significantly associated with lower OP prevalence(OR(95%CI)=0.933(0.902–0.965),β=-0.0694,P<0.001)and higher BMD(OR(95%CI)=3.719(1.750–7.908),β=1.3136,P<0.001).In the animal experiment,both drugs increased bone mass,improved bone microstructure,and promoted osteoblast differentiation.However,metformin appeared more effective in several aspects.It significantly inhibited bone marrow adipocyte and osteoclast differentiation in aged mice compared to simvastatin.Additionally,metformin better promoted the expression of osteoprotegerin(OPG)and collagen type I(Col-I)in bone tissue and maintained the structure and biomechanical properties of cancellous bone.Conclusion:Both drugs significantly preserved bone homeostasis.Particularly,compared with simvastatin,metformin exhibited superior effects in inhibiting adipogenesis,enhancing the OPG/RANKL pathway,and promoting cancellous bone reconstruction.Metformin may serve as a valuable adjunct in preventing and treating OP in the elderly. 展开更多
关键词 senile osteoporosis Mendelian randomization animal study SIMVASTATIN METFORMIN
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T集团供应链金融平台的设计与实现
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作者 王春波 张进 +1 位作者 刘英杰 周鹏 《管理科学与研究(中英文版)》 2024年第5期107-114,共8页
近年,随着T股份有限公司(以下简称T集团)业务规模的高速增长,供应商垫资压力越来越大,不少供应商纷纷提出缩短账期或改变商票结算方式的诉求来以此解决资金占用压力,为了解决供应链上下游中小企业融资难、融资贵、融资慢的问题,T集团推... 近年,随着T股份有限公司(以下简称T集团)业务规模的高速增长,供应商垫资压力越来越大,不少供应商纷纷提出缩短账期或改变商票结算方式的诉求来以此解决资金占用压力,为了解决供应链上下游中小企业融资难、融资贵、融资慢的问题,T集团推出了供应链金融方案并诉诸实施。本文着重解析该公司供应链金融平台的建设要求,包括分析供应链金融平台的建设背景和目标,梳理业务流和数据流,设计供应链金融平台的功能结构,并对供应链金融平台的应用成效进行介绍。 展开更多
关键词 供应链金融 产融生态 融资平台
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地方高校化学基础课虚拟教研室建设的探索与实践 被引量:3
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作者 张进 刘利 +10 位作者 李三喜 葛春华 谢颖 牟林 王爱玲 宫晓杰 何鑫 王鹏 沈薇 刘阳 马睿 《大学化学》 CAS 2023年第10期80-88,共9页
依托学堂在线平台建设地方高校化学基础课虚拟教研室,提出了建设目标和内容。以“总-分”模式分层搭建虚拟教研室组织框架,以“模块化”建设虚拟教研平台。通过协同建设、协调共享线上线下资源,组织开展虚拟教研活动和教师培训提升教师... 依托学堂在线平台建设地方高校化学基础课虚拟教研室,提出了建设目标和内容。以“总-分”模式分层搭建虚拟教研室组织框架,以“模块化”建设虚拟教研平台。通过协同建设、协调共享线上线下资源,组织开展虚拟教研活动和教师培训提升教师教育教学能力,打造和构建地方高校化学基础课共建共享平台和教学学术共同体。 展开更多
关键词 虚拟教研室 协同教研 化学基础课
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铁死亡在高糖诱导的视网膜色素上皮细胞损伤中的作用及机制
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作者 张进 贾爱华 +2 位作者 高岩 刘承秀 梁涛 《国际眼科杂志》 CAS 北大核心 2023年第6期894-899,共6页
目的:观察铁死亡在高糖(HG)诱导的视网膜色素上皮(RPE)细胞损伤中的作用及机制,为糖尿病视网膜病变(DR)的治疗提供新思路。方法:将体外培养的ARPE-19细胞分为正常对照组(NC组)、高糖组(HG组)、高糖+铁死亡抑制剂组(Fer-1组)。采用CCK-8... 目的:观察铁死亡在高糖(HG)诱导的视网膜色素上皮(RPE)细胞损伤中的作用及机制,为糖尿病视网膜病变(DR)的治疗提供新思路。方法:将体外培养的ARPE-19细胞分为正常对照组(NC组)、高糖组(HG组)、高糖+铁死亡抑制剂组(Fer-1组)。采用CCK-8法检测各组细胞活力;使用ELISA试剂盒检测白细胞介素6(IL-6)、IL-1β及单核细胞趋化蛋白-1(MCP-1)的表达水平;使用化验试剂盒检测丙二醛(MDA)、谷胱甘肽(GSH)、谷胱甘肽过氧化物酶4(GPX4)水平;使用铁离子检测试剂盒检测细胞铁含量;通过透射电子显微镜观察细胞线粒体变化;通过Western blotting和免疫荧光染色技术检测铁死亡相关蛋白长链脂酰CoA合成酶4(ACSL4)、GPX4以及血管内皮生长因子(VEGF)蛋白的表达。结果:与NC组相比,HG组细胞活力显著下降,细胞上清液中炎症因子表达水平升高,细胞中氧化应激指标MDA和铁含量显著升高,GSH含量和GPX4活性显著降低(均P<0.01),且线粒体皱缩,ACSL4及VEGF蛋白表达增加,GPX4蛋白表达降低(均P<0.01)。与HG组相比,Fer-1组细胞活力明显增加,细胞上清液中炎症因子表达水平下降,细胞中MDA和铁含量明显下降,GSH含量和GPX4活性显著提高(均P<0.05),且线粒体形态改善,ACSL4及VEGF蛋白表达减少,GPX4蛋白表达升高(均P<0.05)。结论:铁死亡参与高糖诱导的RPE细胞损伤,抑制铁死亡能改善细胞活性,降低炎症及氧化应激水平,减轻高糖诱导的RPE细胞损伤。 展开更多
关键词 铁死亡 糖尿病视网膜病变 视网膜色素上皮细胞 Ferrostatin-1 炎症 氧化应激
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基于OBE理念的CTTM教学模式在急危重症临床教学中的作用研究
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作者 肖文艳 张金 +3 位作者 华天凤 李惠 郑瑶 杨旻 《数理医药学杂志》 CAS 2023年第10期792-796,共5页
目的探索基于成果导向教育(outcome-based education,OBE)理念的案例式立体教学模式(case three-dimensional teaching method,CTTM)在急危重症临床教学中的效果。方法选取在安徽医科大学第二附属医院急诊重症医学科见习的临床医学专业... 目的探索基于成果导向教育(outcome-based education,OBE)理念的案例式立体教学模式(case three-dimensional teaching method,CTTM)在急危重症临床教学中的效果。方法选取在安徽医科大学第二附属医院急诊重症医学科见习的临床医学专业大四年级学生,分为试验组和对照组。试验组实施基于OBE理念的CTTM教学模式,对照组采用传统教学模式。课程结束后,比较两组的理论知识和实践能力得分,并评价两组的教学效果。结果研究共纳入78人,试验组39人、对照组39人。试验组理论知识得分(93.80±2.20 vs.83.60±3.15,P<0.001)和实践能力得分(92.80±2.02 vs.83.50±3.03,P<0.001)均显著高于对照组,试验组的教学效果明显优于对照组(P<0.001)。结论以OBE理念为导向的CTTM教学模式能够明显提升学生的理论和实践能力,教学效果更优,且大部分学生对CTTM教学模式较认可,但其结果还需进一步研究验证。 展开更多
关键词 成果导向教育 案例式立体教学模式 急危重症
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