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Chemical Research in Chinese Universities 2006年第1期22卷 36-39页

作者： WU Chun-zan HUANG jia-xing ZHANG Qi-han XU jia-xi Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871 P. R. China

The reactions of 2,3-dihydro-1,5-benzothiazepines with ethoxyearbonylcarbene undergo complex rearrangements to produce rlng-opening and ring contraction products. Previously it was presumed that the different products were formed via different mechanisms depending on the kind of substituents at the 2-position of 1,5-benzothiazepines. However, on the basis of the further detailed investigation, it was found that all 1,5-benzothiazepines can undergo the same rearrangement to yield both ring-opening and ring contraction products.

关键词： 1,5-Benzothiazepine Ethoxycarbonylcarbene Rearrangement Ring-contraction Ring-opening

Preparation and characterization of oil-soluble In_2O_3 nanoparticles and In_2O_3–SnO_2 nanocomposites and their calcined thin films

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 543-548页

作者： Li-ping Wang Xu-dong Xu jia-xing Wang Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing

Oil-soluble In2O3 nanoparticles and In2O3-SnO2 nanocomposites were prepared in oleylamine via decomposition of metal acety- lacetonate precursors. Thin films of In2O3 and In2O3-SnO2 were obtained by spin-coating solutions of the oil-soluble In2O3 nanoparticles and In2O3-SnO2 nanocomposites onto substrates and then calcining them. Transmission electron microspectroscopy, scanning electron mi- crospectroscopy, atomic force microspectroscopy, X-ray diffraction, ultraviolet-visible absorption, and photoluminescence spectroscopy were used to investigate the properties of the nanoparticles and thin films. The In2O3 nanoparticles were cubic-phased spheres with a diame- ter of-8 nm; their spectra exhibited a broad emission peak centered at 348 nm. The In2O3-SnO2 nanocomposites were co-particles composed of smaller In2O3 particles and larger SnO2 particles; their spectra exhibited a broad emission peak at 355 nm. After the In2O3-SnO2 nano- composites were calcined at 400℃, the obtained thin films were highly transparent and conductive, with a thickness of 30-40 nm; the sur- faces of the thin films were smooth and crack-free.

关键词： indium trioxide tin dioxide nanoparficles nanocomposites thin films calcination

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汤加灾后国际救援的开展及对中国启示

江南社会学院学报 2024年第1期26卷 74-80页

作者：李雪威李佳兴山东大学国际问题研究院山东威海264209 山东大学东北亚学院山东威海264209

“一带一路”沿线国家汤加遭遇突发性自然灾害后,多方国际力量参与到人道主义救援之中,形成多元化救援体系,协调有序展开救灾物资运送、基金募集、服务支援队派遣及灾后恢复重建工作。但此次国际救援也面临诸多困境,如COVID-19的蔓延阻... 详细信息

“一带一路”沿线国家汤加遭遇突发性自然灾害后,多方国际力量参与到人道主义救援之中,形成多元化救援体系,协调有序展开救灾物资运送、基金募集、服务支援队派遣及灾后恢复重建工作。但此次国际救援也面临诸多困境,如COVID-19的蔓延阻碍救援效率、灾害造成的连锁式破坏提升救援难度、太平洋地缘战略竞争对中国参与救援的排斥等。面对上述问题,国际社会签署“无接触式”救援协议,帮助汤加建立完善医疗服务与防疫系统,制定具有针对性的救援方案。借鉴汤加灾后国际救援行动经验,中国应树立友好合作的国际形象,升级和完善现有国际合作机制,重视国内法律的完善与军事力量调用的合法性,综合提升中国在国际救援中的能力建设。

关键词：汤加突发性灾害国际救援合作海外应急管理

鼠妇内生真菌Talaromyces malicola的次生代谢产物研究

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中国中药杂志 2024年第16期49卷 4470-4476页

作者：杨晨宇陈科良刘洋易诚贾兴宝刘云宝中国医学科学院北京协和医学院药物研究所天然药物活性物质与功能国家重点实验室北京100050

对节肢动物鼠妇内生真菌Talaromyces malicola的次生代谢产物进行研究,采用硅胶柱色谱、凝胶柱色谱、半制备液相色谱等进行分离纯化,共从鼠妇内生真菌***发酵物的乙酸乙酯部位中分离鉴定出11个化合物。结合核磁共振波谱、高分辨质谱、... 详细信息

对节肢动物鼠妇内生真菌Talaromyces malicola的次生代谢产物进行研究,采用硅胶柱色谱、凝胶柱色谱、半制备液相色谱等进行分离纯化,共从鼠妇内生真菌***发酵物的乙酸乙酯部位中分离鉴定出11个化合物。结合核磁共振波谱、高分辨质谱、紫外、红外以及圆二色谱等分析方法确定了化合物的结构,分别为talarosesquiterpene A(1)、(3β,5α,6α,15α,22E)-5,6-epoxyergosta-8(14),22-diene-3,7,15-triol(2)、vermistatin(3)、hydroxyvermistatin(4)、bercheminol A(5)、penicillide(6)、lunatinin(7)、penipurdin A(8)、emodin(9)、BE-25327(10)、(-)-regiolone(11)。化合物1为新的diaporol型倍半萜类化合物,化合物2、4~5、7~11为首次从篮状菌属真菌中分离得到。

关键词：鼠妇内生真菌 Talaromyces malicola 次生代谢产物

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某型燃油泵密封端面泄漏故障分析与改进

液压气动与密封 2024年第3期44卷 124-128页

作者：刘雨史泽星马兴家黎锐中航力源液压股份有限公司贵州贵阳550018 空装成都局驻贵阳地区第三军事代表室贵州贵阳550018

针对某型燃油泵控制油路密封端面泄漏故障,运用Pumplinx软件对控制油路流场进行仿真分析,得出了气蚀是导致密封端面漏油的主要原因,并对密封端面结构进行优化设计,最后,通过试验验证了改进措施的有效性。

关键词：燃油泵泄漏气蚀 Pumplinx

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耦合空气系统的燃气轮机拓扑自构建建模方法

航空发动机 2024年第3期50卷 33-39页

作者：郑培英周泽均钟易成董威刘家兴中国航发沈阳发动机研究所沈阳110015 海装广州局驻广州地区第一军事代表室广州510220 南京航空航天大学能源与动力学院南京210016 上海交通大学机械与动力工程学院上海200240

为了实现通用性强、可扩展性好、灵活高效的整机性能模型通用建模,提出了一种拓扑自构建的燃气轮机整机性能通用建模方法。基于面向对象思想,采用模块化技术构建通用部件库,再通过拓扑接口关联部件组成整机模型,建立了适用于不同燃气轮... 详细信息

为了实现通用性强、可扩展性好、灵活高效的整机性能模型通用建模,提出了一种拓扑自构建的燃气轮机整机性能通用建模方法。基于面向对象思想,采用模块化技术构建通用部件库,再通过拓扑接口关联部件组成整机模型,建立了适用于不同燃气轮机类型的整机性能仿真模型。耦合了多支路复杂空气系统迭代求解模型,将其作为部件嵌入整机模型,以取代现有的定比例引气量计算方法。采用跨平台图形开发框架及图像可视化技术,开发了人机交互友好的整机性能预测平台。采用典型双轴燃气轮机算例,与试验结果进行了对比验证。结果表明:对于动力涡轮出口温度,采用恒定引气比方式和当前耦合方法的计算结果与试验结果对比得到的最大误差分别为3.36%和1.31%;对于出口压力的计算在多数工况下的计算精度也有所提高。提出的拓扑自构建的燃气轮机整机性能通用建模方法实现了部件自由搭建及整机拓扑自构建,且耦合空气系统后,整机性能仿真精度显著提高。

关键词：拓扑自构建空气系统整机性能模型燃气轮机

同方期刊数据库博看期刊评论

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新工科背景下应用型土木专业改造升级探索

教育教学论坛 2024年第19期 117-120页

作者：孙明周基胡佳星湖南科技学院土木与环境工程学院湖南永州425199

根据新工科背景下应用型土木工程专业人才的培养目标,提出地方高校改造升级土木工程专业的思路和行动路线,探讨如何在服务国家战略、对接产业行业、跨界整合资源、以学生为中心四个理念的指引下,探索土木工程专业转型、改造和升级的途... 详细信息

根据新工科背景下应用型土木工程专业人才的培养目标,提出地方高校改造升级土木工程专业的思路和行动路线,探讨如何在服务国家战略、对接产业行业、跨界整合资源、以学生为中心四个理念的指引下,探索土木工程专业转型、改造和升级的途径和方式,讨论打造新型工科专业建设平台的要点。从完善模块化课程体系、制订动态专业课程方案、建立课程内容更新机制、优化通识教育课程体系等四个方面建立符合新型工科专业要求的课程体系结构,并建设相应的支撑体系,打造校、政、企协同合作机制,优化升级师资队伍,改变学业评价体系,打造新型工科专业建设匹配的支撑体系,为新工科背景下高素质应用型工程人才培养在实践层面的落实提供参考。

关键词：新工科土木工程改造升级课程体系

Efectiveness of national air pollution control policies on the air quality in metropolitan areas of China

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Journal of Environmental Sciences 2014年第1期26卷 13-22页

作者： Shuxiao Wang jia xing Bin Zhao Carey Jang Jiming Hao State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex US Environmental Protection Agency Research Triangle Park Collaborative Innovation Center for Regional Environmental Quality Tsinghua University

Understanding the effectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the effectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide （SO2） control policy during the llth Five Year Plan period （2006-2010） had succeeded in reducing the national SO2 emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2 and sulfate （SO42-） concentrations by 13%-15% and 8%-10% respectively over east China. The nitrogen oxides （NOx） control policy during the 12th Five Year Plan period （2011-2015） targets the reduction of the national NOx emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NOx emission will reduce the ambient nitrogen dioxide （NO2）, nitrate （NO3-）, 1-hr maxima ozone （03） concentrations and total nitrogen deposition by 8%, 3%-14%, 2% and 2%--4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3-, 1-hr maxima 03 concentrations and total nitrogen deposition by 2%-4%, 1%-%, 0-2% and 1%-2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.

关键词： air pollution control sulfur dioxide nitrogen oxides power plant

A novel glycoside hydrolase 74 xyloglucanase CvGH74A is a virulence factor in Coniella vitis

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Journal of Integrative Agriculture 2020年第11期19卷 2725-2735页

作者： QIN jia-xing LI Bao-hua ZHOU Shan-yue The Key Lab of Integrated Crop Pests Management of Shandong Province/College of Plant Health and Medicine Qingdao Agricultural UniversityQingdao 266109P.R.China

Grape white rot is a destructive fungal disease occurring ***,Coniella vitis was identified as the predominant pathogen causing this disease in *** the periderms of grape shoots are severely degraded by ***,it was speculated that cell wall-degrading enzymes(CWDEs)might play a key role in the pathogenesis of this ***,this study aimed to examine the hydrolytic activity of the CWDEs of *** results showed that xylanase(Xy)and xyloglucanase(XEG)had high levels of hydrolytic activity both in vitro and in ***,a high-virulence fungal strain exhibited higher levels of Xy and XEG activities compared with a low-virulence *** genome of the fungus was found to harbor two XEG-coding genes CvGH74A and CvGH74B,which belonged to the glycoside hydrolase(GH)74 *** expression level of CvGH74A was found to be high during pathogen ***74A gene deletion mutants were generated using the split-marker *** deletion of CvGH74A decreased both the hydrolytic activities of XEG and Xy and also the ability of the fungus to infect the grape *** differences in the hyphal growth,morphology of colonies,or conidiation were found between theΔCvGH74A mutant strains and the wild-type ***,these results suggested that CvGH74A acted as an important virulence factor,and its enzymatic activity might regulate the virulence of the *** study was novel in reporting that GH74 XEG acted as a virulence factor in ***.

关键词： Coniella vitis GH74 grape white rot virulence xyloglucanase

Metal-organic interface engineering for boosting the electroactivity of Pt nanodendrites for hydrogen production

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Journal of Energy Chemistry 2020年第12期29卷 105-112页

作者： Juan Bai Nan jia Pujun Jin Pei Chen jia-xing jiang Jing-Hui Zeng Yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(MOE)Shaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710062ShaanxiChina

Recently, the surface chemical functionalization and morphology control of precious metal nanostructures have been recognized as two efficient strategies for improving their electroactivity and/or selectivity. In this work, 1, 10-phenanthroline monohydrate(PM) functionalized Pt nanodendrites(Pt-NDs) on carbon cloth(CC)(denoted as PM@Pt-NDs/CC) and polyethylenimine(PEI) functionalized Pt-NDs on CC(denoted as PEI@Pt-NDs/CC) are successfully achieved by immersing Pt-NDs/CC into PM and PEI aqueous solutions, respectively. PEI functionalization of Pt-NDs/CC improves its electroactivity for hydrogen evolution reaction(HER) due to local proton enrichment whereas PM functionalization of Pt-NDs/CC improves its electroactivity for formic acid oxidation reaction(FAOR) by facilitating dehydrogenation pathway. With such high activity, a two-electrode electrolyzer is assembled using PM@Pt-NDs/CC as the anodic electrocatalyst and PEI@Pt-NDs/CC as the cathodic electrocatalyst for electrochemical reforming of formic acid, which only requires 0.45 V voltage to achieve the current density of 10 mA cm^(-1) for highpurity hydrogen production, much lower than conventional water electrolysis(1.59 V). The work presents an example of interfacial engineering enhancing electrocatalytic activity and indicates that electrochemical reforming of formic acid is an energy-saving electrochemical method for high-purity hydrogen production.

关键词： Pt nanodendrites Chemical functionalization Catalytic activity Hydrogen evolution reaction Formic acid oxidation reaction