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供应链技术规制与企业出口产品质量

中国工业经济 2024年第6期 80-98页

作者：马野青王冠宇南京大学经济学院南京大学世界经济研究中心

随着全球贸易网络不断深化、贸易格局不断演变,供应链问题已成为关乎企业以高质量产品出口为表现的高质量发展的关键因素。理论上,本文基于新新贸易理论,将以中间品投入为代表的供应链行为纳入企业出口产品质量的决定方程中,发现对供应... 详细信息

随着全球贸易网络不断深化、贸易格局不断演变,供应链问题已成为关乎企业以高质量产品出口为表现的高质量发展的关键因素。理论上,本文基于新新贸易理论,将以中间品投入为代表的供应链行为纳入企业出口产品质量的决定方程中,发现对供应链施加技术规制会通过中间品投入质量和中间品投入成本两个渠道影响企业出口产品质量。实证中,本文借助中国对中间品进口发起的技术性贸易壁垒作为供应链技术规制的准自然实验,利用双重差分法并使用2000—2014年中国企业出口数据进行检验后发现,供应链技术规制会引起企业最终品出口产品质量的上升。从影响机制看,一方面,供应链技术规制会导致企业中间品进口质量上升,进而连带最终品质量升级;另一方面,供应链技术规制并未明显增加企业中间品进口成本,原因在于,由其引致的合规成本被中间品出口商吸收,未转嫁到中间品价格中去。进一步分析发现,供应链技术规制所产生的出口产品质量效应会随着技术规制类别的变化以及企业类型的变化而呈现异质性,这种异质性源于不同类别技术规制所产生的规制效果的差别,以及不同类型企业在产成品与供应链之间的敏感程度、弹性空间、质量转化能力上的差异。本文结论表明,从供应端提高规制要求是提升产品质量以及竞争力的有效方式。

关键词：供应链扶技术规制出口产品质量中间品进口

安徽涡河流域水化学与同位素特征及水体转化关系

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环境科学 2024年第6期45卷 3196-3204页

作者：许金昭刘桂建司雯刘锐佳王冠宇中国科学技术大学地球和空间科学学院合肥230026

以安徽涡河流域为研究区域,通过采集涡河地表水、浅层地下水和中深层地下水样品,运用Gibbs图、离子比例和Mix SIAR模型等方法对各类水体的水化学参数和氢氧同位素进行分析,揭示并量化了各类水体之间的转化关系.结果表明,研究区地表水和... 详细信息

以安徽涡河流域为研究区域,通过采集涡河地表水、浅层地下水和中深层地下水样品,运用Gibbs图、离子比例和Mix SIAR模型等方法对各类水体的水化学参数和氢氧同位素进行分析,揭示并量化了各类水体之间的转化关系.结果表明,研究区地表水和地下水主要呈现中性至弱碱性,地表水的水化学类型以Cl·SO_(4)·HCO_(3)-Na和Cl·SO_(4)-Na型为主,浅层地下水以HCO_(3)-Ca·Mg和HCO_(3)-Mg·Na型为主,中深层地下水主要为Cl·HCO_(3)-Na型.各类水体的水化学特征受到岩石风化、蒸发浓缩及正向阳离子交换等多重因素共同影响.地表水和地下水的δ^(18)O和δ^(2)H分布特征表明大气降水是该区域水体的主要补给来源,且地下水δ^(18)O和δ^(2)H值与K^(+)、Na^(+)、Cl^(-)、SO_(4)^(2-)和NO_(3)-浓度存在显著相关性.根据Mix SIAR模型分析结果,地表水接受大气降水和浅层地下水的贡献率分别为46.5%和53.5%;浅层地下水的补给来源分别为大气降水(57.4%)和地表水(42.6%);中深层地下水的补给主要来自上游地下水的侧向径流补给.

关键词：涡河流域氢氧稳定同位素水化学特征转化关系 MixSIAR模型

Rough communication of crisp concept in fuzzy approximation spaces

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Journal of Systems Engineering and Electronics 2009年第2期20卷 327-331页

作者： wang Hongkai guan Yanyong yu Zhaoxia School of Sciences Univ. of Jinan Jinan 250022 P. R. China

To study the problem of knowledge translation in fuzzy approximation spaces, the concept of rough communication of crisp set in fuzzy approximation spaces is proposed. In a rough communication of crisp set in fuzzy approximation spaces, the problem of uncertainty exists, for each agent has a different language and cannot provide precise communication to each other. By means of some concepts, such as CF rough communication cut, which is a bridge between fuzzy concept and crisp concept, cut analysis of CF rough communication is made, and the relation theorem between CF rough communication and rough communication of crisp concept is obtained. Finally, in order to give an intuitive analysis of the relation between CF rough communication and rough communication of crisp concept, an example is given.

关键词： rough sets fuzzy approximation space crisp concept rough communication CF rough communication cut

辽宁大雅河抽水蓄能电站对大雅河水库影响分析

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东北水利水电 2024年第10期42卷 46-49,72页

作者：洪文彬周立洋王冠宇中水东北勘测设计研究有限责任公司吉林长春130021 国网新源控股有限公司东北开发建设分公司辽宁沈阳110013

本文以辽宁大雅河抽水蓄能电站利用已建大雅河水库作为下水库为例,对大雅河水利枢纽工程改造进行分析,以确保其作为下水库的可行性;并从施工期和正常运行期两个阶段对大雅河水利枢纽现有工程任务的影响作出分析,结果表明施工期对大雅河... 详细信息

本文以辽宁大雅河抽水蓄能电站利用已建大雅河水库作为下水库为例,对大雅河水利枢纽工程改造进行分析,以确保其作为下水库的可行性;并从施工期和正常运行期两个阶段对大雅河水利枢纽现有工程任务的影响作出分析,结果表明施工期对大雅河水利枢纽现有功能没有影响,正常运行期仅年发电量稍有减少,均未对征地移民产生影响。该成果为抽蓄电站建设与运营管理工作起到一定的指导作用,并可为同类工程工作的开展提供参考和借鉴。

关键词：抽水蓄能电站已建水库工程改造影响分析

Investigation on the thermo-chemical reaction mechanism between yttria-stabilized zirconia （YSZ） and calciummagnesium-alumino-silicate （CMAS）

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Frontiers of Materials Science 2015年第1期9卷 93-100页

作者： Dong-Bo ZHANG Bin-Yi wang Jian CAO guan-yu SONG Juan-Bo LIU Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education North China Electric Power University Beijing 102206 China

Thermal barrier coatings （TBCs） with Y2O3-stabilized ZrO2 （YSZ） top coat play a very important role in advanced turbine blades by considerably increasing the engine efficiency and improving the performance of highly loaded blades. However, at high temperatures, environment factors result in the failure of TBCs. The influence of calcium-magnesium-alumino-silicate （CMAS） is one of environment factors. Although thermo-physical effect is being paid attention to, the thermo-chemical reaction becomes the hot-spot in the research area of TBCs affected by CMAS. In this paper, traditional twolayered structured TBCs were prepared by electron beam physical vapor deposition （EB- PVD） as the object of study. TBCs coated with CMAS were heated at 1240℃ for 3 h. Additionally, 15 wt.% simulated molten CMAS powder and YSZ powder were mixed and heated at 1240℃ or 1350℃ for 48 h. SEM and EDS were adopted to detect morphology and elements distribution. According to XRD and TEM results, it was revealed that CMAS react with YSZ at high temperature and form ZrSiO4, Ca0.2Zr0.8O1.8 and Ca0.15Zr0.85O1.85 after reaction, as a result, leading to the failure of TBCs and decreasing the TBC lifetime.

关键词： thermal barrier coating (TBC) yttria-stabilized zirconia (YSZ) calciummagnesium-alumino-silicate (CMAS) thermo-chemical reaction high temperature

In Silico Screening of Potential Spike Glycoprotein Inhibitors of SARS-CoV-2 with Drug Repurposing Strategy

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Chinese Journal of Integrative Medicine 2020年第9期26卷 663-669页

作者： WEI Tian-zi wang Hao WU Xue-qing LU Yi guan Sheng-hui DONG Feng-quan DONG Chen-le ZHU Gu-li BAO yu-zhou ZHANG Jian wang guan-yu LI Hai-ying Department of Biology Southern University of Science and TechnologyShenzhen(518055)GuangdongChina School of Medicine Southern University of Science and TechnologyShenzhen(518055)GuangdongChina School of Biomedical Sciences Li Ka Shing Faculty of Medicinethe University of Hong KongHong Kong SARChina Department of Obstetrics and Gynecology Shenzhen University General HospitalShenzhen(518055)GuangdongChina Clinical Medical Academy Shenzhen UniversityShenzhen(518055)GuangdongChina Department of Cardiology Shenzhen University General HospitalShenzhen(518055)GuangdongChina Department of Obstetrics and Gynecology the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou(325000)ZhejiangChina guangdong Provincial Key Laboratory of Computational Science and Material Design Shenzhen(518055)GuangdongChina guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research Shenzhen(518055)GuangdongChina

Objective:To select potential molecules that can target viral spike proteins,which may potentially interrupt the interaction between the human angiotension-converting enzyme 2(ACE2)receptor and viral spike protein by virtual ***:The three-dimensional(3D)-coordinate file of the receptor-binding domain(RBD)-ACE2 complex for searching a suitable docking pocket was firstly downloaded and ***,approximately 15,000 molecular candidates were prepared,including US Food and Drug Administration(FDA)-approved drngs from DrugBank and natural compounds from Traditional Chinese Medicine Systems Pharmacology(TCMSP),for the docking ***,virtual screening was performed and the binding energy in Autodock Vina was ***,the top 20 molecules with high binding energy and their Chinese medicine(CM)herb sources were listed in this ***:It was found that digitoxin,a cardiac glycoside in DrugBank and bisindigotin in TCMSP had the highest docking ***,two of the CM herbs containing the natural compounds that had relatively high binding scores,Forsyfh/ae frucft/s and/saf/d/s racWx,are components of Lianhua Qingwen(莲花清痕),a CM formula reportedly exerting activity against severe acute respiratory syndrome(SARS)-***,raltegravir,an HIV integrase inhibitor,was found to have a relatively high binding ***:A class of compounds,which are from FDA-approved drugs and CM natural compounds,that had high binding energy with RBD of the viral spike *** work provides potential candidates for other researchers to identify inhibitors to prevent SARS-CoV-2 infection,and highlights the importance of CM and integrative application of CM and Western medicine on treating COVID-19.

关键词： COVID-19 SARS-CoV-2 drug repurposing virtual screening Chinese medicine

Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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China Foundry 2024年第3期21卷 205-212页

作者： guan-yu Jiang Meng-wu Wu Xiao-guang Yang Hui wang yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

Active Ingredients of Reduning Injection Maintain High Potency against SARS-CoV-2 Variants

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Chinese Journal of Integrative Medicine 2023年第3期29卷 205-212页

作者： XIAO Zhen XU Huan QU Ze-yang MA Xin-yuan HUANG Bo-xuan SUN Meng-si wang Bu-qing wang guan-yu Department of Biology School of Life SciencesSouthern University of Science and TechnologyShenzhenGuangdong(518055)China guangdong Provincial Key Laboratory of Computational Science and Material Design ShenzhenGuangdong Province(518055)China Institute of Chemical Biology Shenzhen Bay LaboratoriesShenzhenGuangdong Province(518132)China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing(100191)China Institute for Advanced Study Shenzhen UniversityShenzhenGuangdong Province(518052)China Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxiJiangsu Province(214122)China School of Medicine Life and Health Sciences Chinese University of Hong KongShenzhenGuangdong Province(518172)China Center for Endocrinology and Metabolic Diseases Second Affiliated HospitalThe Chinese University of Hong KongShenzhenGuangdong Province(518172)China

Objective:To investigate the anti-coronavirus potential and the corresponding mechanisms of the two ingredients of Reduning Injection:quercetin and ***:A pseudovirus system was designed to test the efficacy of quercetin and luteolin to inhibit SARS-CoV-2 infection and the corresponding cellular *** was tested for its activities against the pseudoviruses of SARS-CoV-2 and its *** screening was performed to predict the binding sites by Autodock Vina 1.1.230 and *** validate docking results,surface plasmon resonance(SPR)was used to measure the binding affinity of the compounds with various proteins of the *** and luteolin were further tested for their inhibitory effects on other coronaviruses by indirect immunofluorescence assay on rhabdomyosarcoma cells infected with ***:The inhibition of SARS-CoV-2 pseudovirus by luteolin and quercetin were strongly dose-dependent,with concentration for 50%of maximal effect(EC_(50))of 8.817 and 52.98μmol/L,*** cytotoxicity to BHK21-hACE2 were 177.6 and 405.1μmol/L,*** addition,luetolin significantly blocked the entry of 4 pseudoviruses of SARS-CoV-2 variants,with EC50lower than 7μmol/*** screening and SPR confirmed that luteolin binds to the S-proteins and quercetin binds to the active center of the 3CLpro,PLpro,and helicase *** and luteolin showed over 99%inhibition against ***:The mechanisms were revealed of quercetin and luteolin inhibiting the infection of SARS-CoV-2 and its *** Injection is a promising drug for COVID-19.

关键词： Reduning injection Chinese medicine luteolin quercetin SARS-CoV-2

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru wang Bao-Zhi Pan yu-Hang Guo Qing-Hui wang Yao guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model