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Frontiers of Business Research in China 2022年第4期16卷 412-438页

作者： LI qi LIU Ligang SHAO Jianbing Business School Liaoning UniversityShenyang 110036China

Digital transformation provides companies with a productive approach to transforming and upgrading enterprise resources and capabilities and to exploiting external subject forces to unleash and magnify their potential,thus advancing high-quality enterprise ***,using regression analysis of the data of China’s non-financial listed firms from 2007‒2019 obtained by Python,this paper finds that digital transformation has enormously improved enterprise ***,digital transformation has powerfully boosted supply chain integration,which has played a mediation role in the impact of digital transformation on enterprise ***,entrepreneurship plays a positive moderating effect on enterprise performance through supply chain integration during digital *** further heterogeneity analysis finds that digital transformation performs better in large,public,state-owned,mature,and non-manufacturing(service industry)***,the positive effect of digital transformation on enterprise performance and supply chain integration is not significant in small and medium-sized ***,supply chain integration cannot play a mediating role in the impact of digital transformation of manufacturing enterprises upon their *** paper probes the realization mechanism and micro-foundation of digital transformation,and its conclusion contributes to high-quality digital transformation.

关键词： digital transformation supply chain integration entrepreneurship enterprise performance

Unexpected carbon-oxygen bond cleavage of THF promoted by guanidinate titanium complex/lithium diisopropylamide: Synthesis and crystal structure

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Chinese Science Bulletin 2005年第24期50卷 2817-2820页

作者： ZHANG Yong WANG Mei YAO Yingming SHEN qi Key Laboratory of Organic Synthesis Department of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 China Department of Public Course Bengbu Medical CollegeBengbu 233003 China

An unexpected carbon-oxygen bond cleavage of THF (THF = tetrahydrofuran) promoted by guanidinate titanium complex was described. Guanidinate lithium [Pr2iNC(NCy)2]Li (Cy = cyclohexyl) formed in situ reacted with TiCl4(THF)2 in a 2:1 molar ratio to produce the gua- nidinate titanium chloride [Pr2iNC(NCy)2]2TiCl2 (1) in good yield. The reaction of [Pr2iNC(NCy)2]2TiCl2 with lithium diisopropylamide in THF afforded an unexpected [Pr2iNC(NCy)2]2Ti(OBun)2 (2), which was formed by the cleavage of carbon-oxygen bond of THF. Complexes 1 and 2 were fully characterized by elemental analysis, NMR and IR spectroscopies, and X-ray crystal structure determination for complex 2.

关键词：四氢呋喃钛络合物胍配体 C-O键裂合成晶体结构二异丙基酰胺

Web-Based Parallel Monte Carlo Simulation Platform for Financial Computation

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 151-154页

作者： LAN Rong ZHENG Shou-qi GUI Xiao-lin School of Electronic and Information Xi＇an Jiaotong University Xi＇an 710049 Shaanxi China School of Economic and Finance Xi＇an Jiaotong University Xi＇an 710064 Shaanxi China

Using Java, Java enabled Web and object-oriented programming technologies, a framework is designed to or ganize multicornputer system on lntranet quickly to complete Monte Carlo simulation parallelizing, The high-performance computing enviromnent is embedded in Web server so it can be accessed more easily. Adaptive parallelism and eager scheduling algorithm are used to realize load balancing, parallel processing and system fault-tolerance. Independent sequence pseudo-randorn number generator schemes to keep the parallel simulation availability. Three kinds of stock option pricing models as instances, ideal speedup and pricing results obtained on test bed. Now, as a Web service, a high-performance financial derivative security-pricing platform is set up for training and studying. The framework can also be used to develop other SPMD （single procedure multiple data） application. Robustness is still a major problem for further research.

关键词： Web-based simulation distributed computing Monte Carlo simulation stock option pricing

A neutral point potential drift control method for NPC three-level inverter

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High Technology Letters 2021年第3期27卷 256-261页

作者： Wu lin qi Xin Shi Xiangyang Su Tao Tao Yong School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083P.R.China Shunde Graduate School University of Science and Technology BeijingBeijing 100029P.R.China Institute of Microelectronics of the Chinese Academy of Sciences Beijing 102206P.R.China Research Institute of Aero-Engine Beihang UniversityFoshan 528399P.R.China

The output current harmonic distortion of a three-level inverter is less than the traditional twolevel *** voltage stress of the semiconductor switch is low.A neutral point potential drift control method is proposed to solve the problem of the neutral point potential drift of the three-level *** interaction mechanism between the neutral point potential and the space voltage vector is *** small vector output by the inverter is found to be the root cause of the midpoint potential *** is found that the fluctuation of the midpoint potential could be suppressed by increasing the capacitance value of the inverter bus voltage stabilizing ***,it inhibits the fluctuation of the midpoint *** experimental results verify the efficiency and precision of the proposed method.

关键词： neutral-point potential drift space voltage vector three-level inverter small vector output inverter bus voltage stabilizing

Electrical Properties of Periodic Pd/Mo Bimetal Films

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Chinese Physics Letters 1994年第5期11卷 297-300页

作者： WANG Xiaoping ZHAO Texiu WANG Shunxi JI Hang LIANG qi Department of Physics University of Science and Technology of ChinaHefei 230026 High Magnetic Field Laboratory Institute of Plasma PhysicsAcademia SinicaHefei 230031

The electrical resistivity and the temperature coefficient of resistance(TCR)of periodic Pd/Mo bimetal films are reported for the bilayer wavelength in the range 1.5-13nm by varying the ratio of Pd and Mo thicknesses in the temperature range from 77 to *** resistivity is found to be nearly proportional to the inverse of the bilayer *** most striking feature is that the TCR is decreased with bilayer wavelength and the change in sign of the TCR as Pd/Mo thickness ratio is *** into account the effects of electron weak localization in Mo layer,the experimental results can be explained.

关键词： resistivity Periodic inverse

Consumer confidence and consumers’ preferences for infant formulas in China

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Journal of Integrative Agriculture 2019年第8期18卷 1793-1803页

作者： LI Sai-wei ZHU Chen CHEN qi-hui LIU Yu-mei College of Economics and Management China Agricultural University Beijing 100083 P.R.China Center for Food and Health Economic Research College of Economics and Management China Agricultural University Beijing100083 P.R.China

A series of safety incidents related to domestically-produced infant formulas(DIFs) almost destroyed Chinese consumer confidence in domestic dairy products. Understanding consumer confidence and its effect on consumption behavior is important to restore consumer confidence and enhance the competitiveness of domestic dairy industry. This article first measures Chinese consumer confidence in DIFs safety using a two-dimension scale(optimism and pessimism) and then investigates its effect on consumers’ preferences for DIFs through a choice experiment. Involving 450 consumers residing in Beijing, Tianjin and Shijiazhuang, the experiment elicited information on their preferences for DIFs with six attributes(organic raw milk, farm-to-table traceability, region of origin, quality certification, animal welfare, and price). Our analysis yields four findings. First, Chinese consumers still lack confidence in DIFs safety. Second, quality certification is the most preferred product characteristic, followed by organic raw milk and farm-to-table traceability. Third, serving as a signal of high quality, price exerts a positive impact on choices of DIFs for pessimistic consumers. Finally, consumer preferences for farm-to-table traceability and region of origin are significantly influenced by consumer confidence.

关键词： consumer confidence food safety infant formula choice experiment willingness to pay China

Crop Yield and Soil Properties in the First 3 Years After Biochar Application to a Calcareous Soil

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Journal of Integrative Agriculture 2014年第3期13卷 525-532页

作者： LIANG Feng LI Gui-tong LIN qi-mei ZHAO Xiao-rong College of Resources and Environment China Agricultural University

It remains unclear whether biochar applications to calcareous soils can improve soil fertility and crop yield. A long-term field experiment was established in 2009 so as to determine the effect of biochar on crop yield and soil properties in a calcareous soil. Five treatments were： 1） straw incorporation; 2） straw incorporation with inorganic fertilizer; 3）, 4） and 5） straw incorporation with inorganic fertilizer, and biochar at 30, 60, and 90 t ha-l, respectively. The annual yield of either winter wheat or summer maize was not increased significantly following biochar application, whereas the cumulative yield over the first 4 growing seasons was significantly increased. Soil pH, measured in situ, was increased by a maximum of 0.35 units after 2 yr following biochar application. After 3 yr, soil bulk density significantly decreased while soil water holding capacity increased with adding biochar of 90 t ha^-1. Alkaline hydrolysable N decreased but exchangeable K increased due to biochar addition. Olsen-P did not change compared to the treatment without biochar. The results suggested that biochar could be used in calcareous soils without yield loss or significant impacts on nutrient availability.

关键词： biochar calcareous soil crop yield soil pH long-term effect

Field Evaluation of a Duplex RT-RAA Assay for Rapid Detection of SARS-CoV-2--Hebei Province,China,January 2021

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China CDC weekly 2022年第23期4卷 504-508页

作者： Ruiqing Zhang Shunxiang qi Jiandong Li Shiyou Liu Guangyue Han Xinxin Shen qi Li Wenbo Xu Xuejun Ma National Institute for Viral Disease Control and Prevention China CDCBeijingChina Hebei Center for Disease Control and Prevention Shijiazhuang CityHebei ProvinceChina Center for Biosafety Mega-Science Chinese Academy of SciencesWuhan CityHubei ProvinceChina

Introduction:Recently,a local cluster epidemic has occurred in Shijiazhuang City,Hebei *** to promptly identify patients with fever in rural areas was the major reason for this ***:We presented the field evaluation of a new real-time reverse transcription recombinase-aided amplification(RT-RAA)kit incorporating an endogenous internal control in a single-tube format,completed at the Hebei CDC from January 17,2021 to January 27,***:We evaluated the diagnostic performance of RT-RAA assay using automatic extracted RNA of 808 clinical *** with reverse transcriptase real-time quantitative PCR(qRT-PCR),RT-RAA kit achieved 92.41%sensitivity,98.78%specificity and a 96.29%coincidence rate,demonstrating an excellent agreement between the RTRAA assay and qRT-PCR ***,58 samples were extracted using a manual extraction method within 5 minutes,but only samples with high nucleic acid concentration(cycle threshold value not higher than 32)could be stably ***:The RT-RAA is more suitable to meet the needs of rapid,sensitive,and accurate detection in community-level medical institutions.

关键词： Duplex Hebei prompt

Impact of Cerebrovascular Disease Mortality on Life Expectancy in China

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Biomedical and Environmental Sciences 2014年第3期27卷 169-175页

作者： LI Guo qi FAN Jie LIU Jing WANG Wei WANG Miao qi Yue XIE Wu Xiang LIU Jun ZHAO Fan LI Yan ZHAO Dong Department of Epidemiology Beijing An Zhen HospitalCapital Medical UniversityBeijing Institute of HeartLung and Blood Vessel Diseases

Objective To evaluate the impact of cerebrovascular disease mortality on life expectancy （LE） in China in 2010 compared with 2005, and to identify the high-risk population （age, sex, and region） where cerebrovascular disease mortality has had a major impact on LE. Methods LE and cause-eliminated LE were calculated by using standard life tables which used adjusted mortality data from the Death Surveillance Data Sets in 2005 and 2010 from the National Disease Surveillance System. Decomposition was used to quantitate the impact of cerebrovascular disease in different age groups. Results LE in China was 73.24 years in 2010, which was higher in women and urban residents compared with men and rural residents. The loss of LE caused by cerebrovascular disease mortality was 2.26 years, which was higher in men and rural residents compared with women and urban residents. More than 30% of the loss of LE were attributed to premature death from cerebrovascular disease in people aged 〈65 years. Compared with 2005, LE in 2010 increased by 0.92 years. The reduction of cerebrovascular disease mortality in urban residents contributed 0.45 years to the increase of LE, but the increase of cerebrovascular disease mortality caused a 0.12-year loss of LE in rural residents. Conclusion Cerebrovascular disease mortality had a major impact on LE in China, with a significant difference between urban and rural residents. LE is likely to be further increased by reducing cerebrovascular disease mortality, and special attention should be paid to reducing premature deaths in people aged 〈65 years.

关键词： Cerebrovascular disease Life expectancy Loss of Life

Role of oxygen and ammonium ions in silver leaching with thiosulfate–ammonia–cupric ions

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Rare Metals 2014年第2期33卷 225-229页

作者： Valentin Ibarra-Galvan Alejandro López-Valdivieso Xiong Tong Yi-qi Cui Faculty of Chemistry Colima University Minerals Engineering Area Institute of Metallurgy Autonomous University of San Luis Potosi Faculty of Land and Resource Engineering Kunming University of Science and Technology

The dissolution of silver with thiosulfate and copper ions was studied in a batch-stirred reactor at 25 °C in the absence and presence of various ammonium ions and oxygen concentrations in the aqueous solution. Leaching silver with 4 mg L-1oxygen in the aqueous solution requires high concentration of ammonium and thiosulfate ions. High silver dissolution is achieved at pH of high cupric tetraamine concentration, around pH 9.8, but a high degradation of thiosulfate ions is resulted from their oxidation by the presence of oxygen. When the oxygen concentration is below 1 mg L-1, dissolved silver thiosulfate species are fairly stable and the degradation of thiosulfate ions in the aqueous solution is low. Under these conditions,high silver dissolution is attained using low thiosulfate concentration. At the oxygen concentration of 4 mg L-1,dissolved silver thiosulfate species precipitate out of the aqueous solution significantly affecting silver *** of dissolved silver thiosulfate species occurs because of oxidation of the thiosulfate bonding to the silver.

关键词： Silver Thiosulfate leaching Non-cyanide silver leaching Cupric tetraamine Oxygen