检索结果-南通市图书馆

Policy Analysis and Development Evaluation of Digital Trade:An International Comparison

在线全文

学校读者我要写书评

暂无评论

China & World Economy 2019年第3期27卷 49-75页

作者： Shuzhong Ma jiwen Guo Hongsheng zhang School of Economics Zhejiang University China

As an extension of traditional trade,digital trade is a new type of trade in the era of the digital economy.In this paper,we first analyze the digital trade-related strategies of eight leading economies through word clouds and dissect China s digital trade-related policies using the word frequency method by sorting through the digital trade-related policy documents of 26 economies and Chinese provinces.We then evaluate the status quo of digital trade development in 111 countries and Chinese provinces by building a digital trade index system to determine the development environment and market potential.The results show that all countries attach great importance to digital technology,data and government guidance in the development of digital trade.The results also reveal that"development,""service"and"construction"are the three most frequently used words in various Chinese documents.The overall level of China s digital trade is at the global vanguard,but is characterized by uneven regional development.In the era of digital trade,traditional international trade theory is also in urgent need of breakthroughs and innovation.

关键词： cross-border e-commerce development evaluation digital trade intelligent manufacturing international trade theories

Resistive Switching Behavior of Ag/Mg0.2Zn0.8O/ZnMn2O4/p^+-Si Heterostructure Devices for Nonvolatile Memory Applications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2017年第1期32卷 29-32页

作者：韦长成王华 XU jiwen zhang Yupei zhang Xiaowen YANG Ling School of Materials Science and Engineering Guilin University of Electrnic TechnologyGuilin 541004China

The Ag/Mg0.2Zn0.8O/ZnMn2O4/p^＋-Si heterostructure devices were fabricated by sol-gel spin coating technique and the resistive switching behavior,conduction mechanism,endurance characteristic,and retention properties were investigated.A distinct bipolar resistive switching behavior of the devices was observed at room temperature.The resistance ratio R_（HRS）/RLRS of high resistance state and low resistance state is as large as four orders of magnitude with a readout voltage of 2.0 V.The dominant conduction mechanism of the device is trap-controlled space charge limited current（SCLC）.The devices exhibit good durability under 1×10^3cycles and the degradation is invisible for more than 10^6 s.

关键词： heterostructure Ag/Mg0.2Zn0.8O/ZnMn2O4/p^＋-Si devices resistive switching properties

Variant rs8400 enhances ALKBH5 expression through disrupting miR-186 binding and promotes neuroblastoma progression

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Cancer Research 2023年第2期35卷 140-162页

作者： Qian Guan Huiran Lin Wenfeng Hua Lei Lin Jiabin Liu Linqing Deng Jiao zhang jiwen Cheng Zhonghua Yang Yong Li Jun Bian Haixia Zhou Suhong Li Li Li Lei Miao Huimin Xia Jing He Zhenjian Zhuo School of Medicine South China University of TechnologyGuangzhou 510006China Department of Pediatric Surgery Guangzhou Institute of PediatricsGuangdong Provincial Key Laboratory of Research in Structural Birth Defect DiseaseGuangdong Provincial Clinical Research Center for Child HealthGuangzhou Women and Children's Medical CenterGuangzhou Medical UniversityGuangzhou 510623China Faculty of Medicine Macao University of Science and TechnologyMacao 99078China Research Institute for Maternal and Child Health Guangdong Second Provincial General HospitalGuangzhou 510317China Department of Pediatric Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Pediatric Surgery the Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710004China Department of Pediatric Surgery Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Pediatric Surgery Hunan Children's HospitalChangsha 410004China Department of General Surgery Xi'an Children's HospitalXi'an Jiaotong University Affliated Children's HospitalXi'an 710003China Department of Hematology The Second Affliated Hospital and Yuying Children's Hospital of Wenzhou Medical UniversityWenzhou 325027China Department of Pathology Children Hospital and Women Health Center of ShanxiTaiyuan 030013China Kunming Key Laboratory of Children Infection and Immunity Yunnan Key Laboratory of Children's Major Disease ResearchYunnan Institute of Pediatrics ResearchYunnan Medical Center for Pediatric DiseasesKunming Children's HospitalKunming 650228China Laboratory Animal Center School of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Objective:AlkB homolog 5(ALKBH5)has been proven to be closely related to tumors.However,the role and molecular mechanism of ALKBH5 in neuroblastomas have rarely been reported.Methods:The potential functional single-nucleotide polymorphisms(SNPs)in ALKBH5 were identified by National Center for Biotechnology Information(NCBI)dbSNP screening and SNPinfo software.TaqMan probes were used for genotyping.A multiple logistic regression model was used to evaluate the effects of different SNP loci on the risk of neuroblastoma.The expression of ALKBH5 in neuroblastoma was evaluated by Western blotting and immunohistochemistry(IHC).Cell counting kit-8(CCK-8),plate colony formation and 5-ethynyl-2'-deoxyuridine(EdU)incorporation assays were used to evaluate cell proliferation.Wound healing and Transwell assays were used to compare cell migration and invasion.Thermodynamic modelling was performed to predict the ability of miRNAs to bind to ALKBH5 with the rs8400 G/A polymorphism.RNA sequencing,N6-methyladenosine(mA)sequencing,mA methylated RNA immunoprecipitation(MeRIP)and a luciferase assay were used to identify the targeting effect of ALKBH5 on SPP1.Results:ALKBH5 was highly expressed in neuroblastoma.Knocking down ALKBH5 inhibited the proliferation,migration and invasion of cancer cells.miR-186-3p negatively regulates the expression of ALKBH5,and this ability is affected by the rs8400 polymorphism.When the G nucleotide was mutated to A,the ability of miR-186-3p to bind to the 3'-UTR of ALKBH5 decreased,resulting in upregulation of ALKBH5.SPPI is the downstream target gene of the ALKBH5 oncogene.Knocking down SPP1 partially restored the inhibitory effect of ALKBH5 downregulation on neuroblastoma.Downregulation of ALKBH5 can improve the therapeutic efficacy of carboplatin and etoposide in neuroblastoma.Conclusions:We first found that the rs8400 G>A polymorphism in the m6A demethylase-encoding gene ALKBH5 increases neuroblastoma susceptibility and determines the related mechanisms.The aberrant regulation of ALKBH5 by miR-186-3

关键词： Neuroblastoma risk ALKBH5 polymorphism progression

Crustal velocity structure in the Emeishan large igneous province and evidence of the Permian mantle plume activity

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2015年第5期58卷 1133-1147页

作者： XU Tao zhang ZhongJie LIU BaoFeng CHEN Yun zhang MingHui TIAN XiaoBo XU YiGang TENG jiwen State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences Geophysical Exploration Center China Earthquake Administration University of Chinese Academy of Sciences State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences

The Emeishan large igneous province(ELIP) in SW China is interpreted to be associated with an ancient mantle plume. Most of the constraints on the role of mantle plume in the generation of the Emeishan flood basalts were provided by geological and geochemical methods, but the geophysical investigation is very limited. In order to better understand the deep structure and features of ELIP, we have studied the crustal velocity structure using the data acquired from the Lijiang-Panzhihua-Qingzhen wide-angle seismic profile. This profile crosses the three sub-zones of the ELIP(the inner, intermediate, and outer zones), divided based on the differential erosion and uplift of the Maokou limestone. The results provided by the active source seismic experiment demonstrate:(1) The average depth of the crystalline basement along the profile is about 2 km.(2) The middle crust in the Inner Zone is characterized by high-velocity anomalies, with the average velocity of 6.2-6.6 km/s, which is about 0.1– 0.2 km/s higher than the normal one. The velocity of the lower crust in the inner zone is 6.9-7.2 km/s, higher than those observed in the intermediate and outer zones(6.7-7.0 km/s). Relatively low velocity anomalies appear in the upper, middle and lower crusts near the junction of the inner zone and intermediate zone, probably due to the effect of the Xiaojiang fault(XJF).(3) The average velocity of the crust is comparatively low on both sides of XJF, especially on the east side, and the average velocity of the consolidated continental crust is also low there. This may suggest that the XJF extends at least down to 40 km deep, even beyond through the crust.(4) The depth to the Moho discontinuity decrease gradually from 47-53 km in the inner zone, via 42-50 km in the intermediate zone to 38-42 km in the outer zone. In the inner zone, the Moho uplifts locally and the(consolidated) crust is characterized by high-velocity anomalies, which are likely related to intensive magma intrusion and underplating associated with melting of plume

关键词：地壳速度结构峨眉山大火成岩省二叠纪地幔热柱峨眉山地幔柱证据峨眉山玄武岩地球物理调查

Methyl chloride dehydration with ionic liquid based on COSMO-RS model

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2021年第3期6卷 413-421页

作者： Zhenhang Wang Shengli Liu Yifan Jiang Zhigang Lei Jie zhang Ruisong Zhu jiwen Ren State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBox 266Beijing100029China Zhejiang Cenway Materials Co. Ltd.JiaxingZhejiang314000China

A suitable ionic liquid for methyl chloride drying experiment was screened out from 210 ionic liquids by COSMO-RS model.Moreover,the experimental mechanism of ionic liquids drying is further explained by the COSMO-RS model,and it is further confirmed by analyzing the binding energy.The solubility of methyl chloride in[EMIM][BF4]and TEG and[EMIM][BF4]+H2O was completed,and the experimental results well proved the reliability of the UNIFAC-Lei model.The unknown interaction parameters were obtained through the solubility data of this work and the experimental data in the literatures.The methyl chloride drying experiment was completed in the laboratory,and the water content of the methyl chloride can be reduced to below 200 ppm.The simulation of the methyl chloride drying process using[EMIM][BF4]or TEG as absorbents was carried out by ASPEN software on an industrial scale.The final simulation results show that the[EMIM][BF4]drying process has lower energy consumption and better drying effect.

关键词： Ionic liquids(ILs) COSMO-RS model UNIFAC-Lei model Gas drying Process simulation

Analytical design of PI controller for AQM with robustness adjustability

在线全文

学校读者我要写书评

暂无评论

Frontiers of Electrical and Electronic Engineering in China 2008年第2期3卷 240-245页

作者： Danying GU jiwen YANG Weidong zhang Shanghai Jiao Tong University Shanghai 200240China

Based on a linearized TCP/AQM model,a new proportional integral(PI)controller design approach is proposed.This analytical approach applies H_(∞) optimization and internal model control(IMC)theory to design active queue management(AQM)routers that support transmission control protocol(TCP)flows.The most important feature of the proposed scheme lies in that it can be explicitly tuned with a single parameter for the trade-off between performance and stability of the AQM control system.It is thus flexible and easy to use in design.The proposed method and the designed PI controller are verified and compared with other existing AQM schemes using ns-2 simulator.The results show the advantages of the new PI controller design approach for AQM routers supporting TCP flows.

关键词： active queue management(AQM) proportional integral(PI)controller transmission control pro-tocol(TCP) time delay robustness

Resistance Switching Properties of Ag/Zn Mn_2O_4/p-Si Fabricated by Magnetron Sputtering for Resistance Random Access Memory

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2015年第6期30卷 1159-1162页

作者：王华 LI Zhida XU jiwen zhang Yupei YANG Ling QIU Wei School of Materials Science and Engineering Guilin University of Electronic Technology

A resistance random access memory（RRAM） with a structure of Ag/ZnMn2O4/p-Si was fabricated by magnetron sputtering method. Reliable and repeated switching of the resistance of ZnMn2O4 fi lms was obtained between two well-defi ned states of high and low resistance with a narrow dispersion and 3V switching voltages. Resistance ratio of the high resistance state and low resistance state was found in the range of around 10^3 orders of magnitude and up to about 10^3 test cycles. The retention time of Ag/ZnMn2O4/p-Si device is longer than 10^6 seconds and the resistance ratio between two states remains higher than 10^3 at room temperature, showing a remarkable reliability performance of the RRAM devices for nonvolatile memory application. The equivalent simulation circuits for HRS（high resistance state） and LRS（low resistance state） were also studied by impedance spectroscopy.

关键词： ZnMn2O4 resistance switching properties RRAM magnetron sputtering

A Thickness Gauge for the Lithosphere Based on Ce/Yb and Sm/Yb of Mantle–Derived Magmatic Rocks

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2018年第6期92卷 2120-2135页

作者： WU Zhenhan Patrick J. BAROSH zhang Qichao WU jiwen YANG Yan Chinese Academy of Geological Sciences Beijing 100037China P.J.Barosh and Associates 103 Aaron Ave.BristolRI02809USA Institute of Karst Geology Chinese Academy of Geological SciencesGuilin 541004China

A new method for determining the partial melting depth of mantle-derived magma and lithospheric thickness in continental regions is derived from REE geochemistry. This effective technique uses variations in the Ce/Yb and Sm/Yb ratios found in mainly volcanic rocks in continental China. The ratios change with the depth of origin consistent with the correlation between lithospheric thickness and the Ce/Yb and Sm/Yb ratios found in oceanic basalt. These ratios increase exponentially with the depth of origin, the lithospheric thickness, of a wide variety of Cenozoic volcanic basalt and Paleozoic kimberlite in the North China Craton, northeastern China continent and vicinity. This functional relationship with depth is shown in a plot of the ratios that forms a concordia curve, which is closely expressed by formulas using 8–degree polynomials. These provide a more accurate gage in measuring the lithospheric thickness than the traditional geophysical methods. When applied to volcanic rock of different ages it also reveals how the thickness has changed over time and thus, greatly aids the understanding of the tectonic history. Relations between the COcontent, mineral reactions and pressure in the upper asthenosphere beneath the base of the lithosphere appears to affect the proportions of REE in partial melts and brings about a close correlation between lithospheric thickness and the Ce/Yb and Sm/Yb ratios in mantle–derived magmatic rock. This thickness gauge, for both continental and oceanic lithosphere, provides a new approach in analyzing the lithospheric thickness in different tectonic settings and geologic times.

关键词： Ce/Yb and Sm/Yb ratios mantle–derived magmatic rock lithospheric thickness correlation analysis North China Craton

Simultaneous acquisition of multi-nuclei enhanced NMR/MRI by solution-state dynamic nuclear polarization

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第7期59卷 830-835页

作者： Yugui He Zhen zhang jiwen Feng Chongyang Huang Fang Chen Chaoyang Liu Maili Liu State Key Laboratory of Magnet Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China University of Chinese Academy of Sciences Beijing 100048China

Dynamic nuclear polarization(DNP) has become a very important hyperpolarization method because it can dramatically increase the sensitivity of nuclear magnetic resonance(NMR) of various molecules.Liquid-state DNP based on Overhauser effect is capable of directly enhancing polarization of all kinds of nuclei in the system.The combination of simultaneous Overhauser multi-nuclei enhancements with the multi-nuclei parallel acquisitions provides a variety of important applications in both MR spectroscopy(MRS) and image(MRI).Here we present two simple illustrative examples for simultaneously enhanced multi-nuclear spectra and images to demonstrate the principle and superiority.We have observed very large simultaneous DNP enhancements for different nuclei,such as ~1H and ^(23)Na,~1H and ^(31)P,^(19)F and ^(31)P,especially for the first time to report sodium ion enhancement in liquid.We have also obtained the simultaneous images of ^(19)H and ^(31)P,^(19)F and ^(31)P at low field by solution-state DNP for the first time.

关键词：动态核极化核磁共振溶液状态多核捕获磁共振波谱 DNP er效应