检索结果-南通市图书馆

Synthesis of Chiral Hydantoins and Thiazolidinediones via Iridium-Catalyzed Asymmetric Hydrogenation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2022年第7期40卷 819-824页

作者： Yu nie jing Li Qianjia Yuan Wanbin Zhang Shanghai Key Laboratory of Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China College of Chemistry Zhengzhou University75 Daxue RoadZhengzhouHenan 450052China

Herein,we report an iridium-catalyzed asymmetric hydrogenation of hydantoin and thiazolidinedione derived exocyclic alkenes using our developed BiphPHOX as a ligand.The transformation shows good functional group tolerance,and gives the hydrogenated prod-ucts with excellent yields(up to 99%)and enantioselectivities(up to 98%ee).A gram-scale reaction was also carried out,and pro-vided the hydrogenated product in excellent yield with no erosion in enantioselectivity.Finally,the transformation of the hydrogen-ated product provided an efficient approach for the synthesis of the intermediate of a HIV protease inhibitor.

关键词： Hydantoins Thiazolidinediones Phosphine-oxazoline ligand Iridium Asymmetric catalysis

Finite Difference Method for Inhomogeneous Fractional Dirichlet Problem

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical Mathematics(Theory,Methods and Applications) 2022年第3期15卷 744-767页

作者： jing Sun Weihua Deng Daxin nie School of Mathematics and Statistics Gansu Key Laboratory of Applied Mathematics and Complex SystemsLanzhou UniversityLanzhou 730000P.R.China

We make the split of the integral fractional Laplacian as(−△)^(s)u=(−△)(−△)^(s−1)u,where s∈(0,1/2)∪(1/2,1).Based on this splitting,we respectively discretize the oneand two-dimensional integral fractional Laplacian with the inhomogeneous Dirichlet boundary condition and give the corresponding truncation errors with the help of the interpolation estimate.Moreover,the suitable corrections are proposed to guarantee the convergence in solving the inhomogeneous fractional Dirichlet problem and an O(h^(1+α)2s))convergence rate is obtained when the solution u∈C^(1,α)(Ω_(n)^(δ)),where n is the dimension of the space,∈(max(0,2s−1),1],δis a fixed positive constant,and h denotes mesh size.Finally,the performed numerical experiments confirm the theoretical results.

关键词： One-and two-dimensional integral fractional Laplacian Lagrange interpolation operator splitting finite difference the inhomogeneous fractional Dirichlet problem error estimates

Propagation of Rayleigh-type surface waves in a layered piezoelectric nanostructure with surface effects

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2022年第3期43卷 327-340页

作者： Lele ZHANG jing ZHAO Guoquan nie Jinxi LIU State Key Laboratory of Mechanical Behavior and System Safety of Tra±c Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Key Laboratory of Mechanics of Intelligent Materials and Structures Department of Engineering MechanicsShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture Shijiazhuang Institute of Railway TechnologyShijiazhuang 050041China

This work investigates the dispersion properties of Rayleigh-type surface waves propagating in a layered piezoelectric nanostructure composed of a piezoelectric nanofilm over an elastic substrate.As one of the most important features of nanostructures,surface effects characterized by surface stresses and surface electric displacements are taken into account through the surface piezoelectricity theory and the nonclassical mechanical and electrical boundary conditions.Concrete expressions of the dispersion equation are derived,and numerical results are provided to examine the effects of several surface-related parameters,including the surface elasticity,surface piezoelectricity,surface dielectricity,surface density,as well as surface residual stress,on the dispersion modes and phase velocity.The size-dependent dispersion behaviors occurring with surface effects are also predicted,and they may vanish once the thickness of the piezoelectric nanofilm reaches a critical value.

关键词： surface effect surface piezoelectricity dispersion behavior piezoelectric nanofilm Rayleigh wave

How to Improve the Team Innovation Performance by Means of a Double Approach:Innovative Leadership and Innovation-Oriented Human Resource Management Practices

在线全文

学校读者我要写书评

暂无评论

Frontiers of Business Research in China 2023年第2期17卷 215-238页

作者： YIN Kui ZHAO jing nie Qi School of Economics and Management University of Science and Technology BeijingBeijing 100083China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Innovative leadership and innovation-oriented human resource management practices(HRMPs)are soft and hard measures,respectively,that promote team innovation performance(TIP).This study is based on human capital theory,integrating the leadership process model and the content-process-results framework of HRM(HRM-CPO),and using data from 259 teams and 1,278 employees in leader-subordinate pairs.Results show that team human capital(THC)is an important mediator in explaining the impact of introducing innovation-oriented practices on TIP.In addition,innovative leadership can improve THC by increasing the level of implemented innovation-oriented HRMPs,thereby affecting TIP.The study extends the level at which HRMPs and leadership behaviors work together and responds to the call for integration of two major research fields of HRM and leadership behavior.

关键词： innovative leadership innovation-oriented HRMPS innovation performance human capital leadership process model

Establishment of image-guided radiotherapy of orthotopic hepatocellular carcinoma mouse model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

动物模型与实验医学(英文) 2023年第5期6卷 419-426页

作者： Kaixiao Zhou Yabo Jiang Shuang Feng Wei Mo Jing Nie Jianping Cao Yang Jiao School of Radiation Medicine and Protection State Key Laboratory of Radiation Medicine and ProtectionSoochow UniversitySuzhouChina The Six Department of Hepatic Surgery Eastern Hepatobiliary Surgery HospitalNavy Military Medical UniversityShanghaiChina Department of Radiotherapy Eastern Hepatobiliary Surgery HospitalNavy Military Medical UniversityShanghaiChina

Background:Hepatocellular carcinoma(HCC)is the most common type of liver cancer.Recently,developments in radiotherapy technology have led to radiotherapy becoming one of the main therapeutics of HCC.Therefore,a suitable animal model for radiotherapy of the orthotopic HCC mouse model is urgently needed.Methods:In the present study,Hepa1-6 cells were injected into the liver of C57BL/6 mice in situ to mimic the pathological characteristics of the original HCC.Tumor formation was monitored by applying magnetic resonance imaging techniques and verified by H&E histopathological staining,AFP staining,and Ki67 staining.A single dose of 10 Gy X-ray was applied to simulate clinical radiotherapy plans using image-guided radiotherapy(IGRT)equipment.The efficiency of radiotherapy was then assessed by examining tumor size and weight one week after radiation.Cleaved-caspase3 staining and TUNEL were used to assess apoptosis in tumor tissues.Results:Intrahepatic tumor development was detected in the liver according using MRI.A high-density shadow could be seen 10 days after cell injection,which indicated the formation of HCC in vivo.The tumors grew steadily bigger,and underwent precision radiotherapy 20 days after injection.The typical pathological characteristics of HCC,such as large,deeply stained nuclei and irregular cell size,were visible with H&E staining.After radiotherapy,significantly higher expression of the immunohistochemical markers Ki67 and AFP were detected in tumor tissue than in the nearby normal tissue.Compared with the control group,the tumor volume(p=0.05)and weight(p<0.05)of the irradiated group were significantly reduced.In addition,a higher frequency of apoptosis was identified in irradiated HCC tumor tissue using the TUNEL and cleaved-caspase3 staining assay.Conclusions:In a well-established orthotopic HCC model,MRI was utilized to monitor the formation of tumors,and IGRT was used to simulate clinical radiotherapy.The present study could provide a suitable preclinical system for HCC radiotherapyrelated stud

关键词： hepatocellular carcinoma orthotopic model radiotherapy

Complicated Bosworth fracture-dislocation:A case report and review of the literature

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Traumatology 2023年第6期26卷 344-350页

作者： Dong-Peng Tu Li-Jun Cai Hong-Yong Zhao Li-Gang Huang Jing Nie Department of Orthopaedics Hangzhou Xiaoshan Orthopaedic Hospital of Traditional Chinese MedicineHangzhou311261China

Bosworth fracture and dislocation is relatively rare,accounting for about 1%of ankle fractures.It is characterized by the proximal fibula fracture embedded in the posterolateral distal tibia.Due to an insufficient understanding of this fracture,it is easy to cause missed diagnosis and misdiagnosis in clinical practice.Due to the insertion of the fracture,it is challenging to perform closed reduction,and improper treatment is easy to cause complications.Surgical treatment is recommended for this type of fracture.In order to improve the understanding of orthopedic surgeons about Bosworth fracture and dislocation,this paper reports the diagnosis and treatment of 2 cases of Bosworth fracture and dislocation,and reviews the literature on Bosworth fracture's mechanism,diagnosis,classification,complications,and treatment options in recent years.

关键词： Bosworth fracture Ankle fractures Fracture-dislocation

Emergency material scheduling optimization model and algorithms:A review

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2019年第5期6卷 441-454页

作者： Hui Hu jing He Xiongfei He Wanli Yang Jing Nie Bin Ran School of Automobile Chang'an University Xi'an 710064 China School of Civil and Environmental Engineering University of Wisconsin at Madison Madison WI 53706 USA

In the emergency management of disruptions,efficient emergency material scheduling(EMS) is a key factor to save people’s lives and reduce loss.Based on the literature of EMS and related areas in recent years,the research was summarized from two aspects of EMS optimization model and algorithms.It is concluded that the EMS optimization models mainly aim at the shortest time,shortest distance,minimum cost,maximum satisfaction and fairness,etc.The constraints usually include the quantity of supply depots,relief supply and vehicles,the types of commodities,the road network conditions,the budgets and the demand forecast of emergency materials.Multi-objective model is more complex and it usually considers more than one objective.To find the optimized solution,the multiobjective model with complex constraints needs more efficient algorithms.The existing algorithms,including mathematic algorithm and heuristic algorithm,have been categorized.For NP-hard(non-deterministic polynomial hard) problems,heuristic algorithms should be designed,which mainly include genetic algorithm(GA),ant colony optimization(ACO),particle swarm optimization(PSO),etc.Based on the characteristics of the optimization model and various algorithms,appropriate algorithm or tools should be chosen and designed to obtain the optimized solution of EMS model.Finally,the development trends of EMS optimization model and algorithm in the future are proposed.

关键词： Emergency material scheduling (EMS) Optimization model Heuristic algorithm Disruption

Health risk assessment of dietary exposure to polycyclic aromatic hydrocarbons in Taiyuan, China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2014年第2期26卷 432-439页

作者： Jing Nie jing Shi Xiaoli Duan Beibei Wang Nan Huang Xiuge Zhao Chinese Research Academy of Environmental Sciences State Key Lab of Environmental Criteria and Risk Assessment Soil and Water Science College of Resources and Environmental Sciences China Agricultural University Department of Safety Engineering China Institute of Industrial Relations

Sixteen polycyclic aromatic hydrocarbons （PAHs） were determined in 24 duplicate-diet samples from people in Taiyuan during summer and winter in 2009. Dietary intake of PAHs for 2862 participants was subsequently estimated by a survey in Taiyuan. Results from these 24 samples were compared with a raw food study in Taiyuan in 2008. Three main sources of dietary PAHs are vegetables, wheat flour and fruits, the sum of which contributes 75.95% of PAHs in dietary food. Compared to the estimated value in raw food, much more B[a]Peq （benzo[a]pyrene equivalents） were detected in food samples collected in the duplicate-diet study in Taiyuan （60.75 ng/day）. The cooking process may introduce more B[a]Peq into food, and the relative contribution of 16 PAHs in the diet would be changed during the cooking procedure.

关键词： dietary exposure food health risk assessment polycyclic aromatic hydrocarbons （PAHs） benzo[a]pyrene

High dynamic range image reconstruction for multi-bit quanta image sensor

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2022年第9期18卷 553-558页

作者： GAO jing SHANG Zongyao nie Kaiming LUO Tao Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology School of MicroelectronicsTianjinUniversityTianjin 300072China College of Intelligence and Computing Tianjin UniversityTianjin 300072China

An adaptive thresholds algorithm is proposed in this letter, which is used to determine the global optimal thresholds for multi-bit quanta image sensor(MB-QIS). Firstly, the senor model of MB-QIS is set up. Then global optimal thresholds theory is analyzed and a thresholds optimization algorithm based on the binary search is designed to determine the optimal global thresholds. Finally, the high dynamic range(HDR) images are reconstructed by the noniterative maximum likelihood estimation(MLE) image reconstruction method. The results of simulation prove that HDR imaging of MB-QIS is realized by the proposed method effectively.

关键词： image HDR dynamic