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Ru(II)-Catalyzed ortho C-H Allylation of N-Aryl-7-azaindoles with 2-Methylidene Cyclic Carbonate

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Chinese Journal of Chemistry 2024年第9期42卷 985-989页

作者： jing Zhang quan-Jian Luo Han-Chi wang jin-Heng Li Bo Sun State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology QingdaoShandong266042China State key Laboratory of Applied Organic Chemistry Lanzhou University LanzhouGansu 7300ooChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A Ru(II)-catalyzed ortho allylation reaction of N-aryl-7-azaindole with readily available 2-methylidene cyclic carbonate has been *** reaction is an effective pathway for synthesizing 7-azaindole derivatives with a wide scope of substrates and high *** addition,the method can be extended to the allylation of other heterocyclic compounds and several cyclic carbonates,highlighting the practicality of this strategy for synthesis.

关键词： Ru(II) Allylation N-Aryl-7-azaindoles Cyclic carbonates Heterocyclic compounds C-H activation

Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System

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China Ocean Engineering 2024年第1期38卷 29-41页

作者： LI Yan-wei LIU Xiu-quan wang jin-long CHEN Guo-ming CHANG Yuan-jiang SHENG Lei-xiang Centre for Offshore Engineering and Safety Technology China University of PetroleumQingdao 266580China National Engineering Laboratory of Offshore Geophysical and Exploration Equipment China University of PetroleumQingdao 266580China China CNOOC Research Institute Co. Ltd.Beijing 100028China

The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of *** approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex *** accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβ*** analysis program is also developed in MATLAB for dynamic *** simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation *** bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and *** platform navigation speed range under the safety limits of risers expands with the new hang-off system in use.

关键词： deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method

A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan wang Fanjiang Xu quan Zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

Fatal visceral disseminated varicella-zoster virus infection in a renal transplant recipient:A case report

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World Journal of Clinical Cases 2021年第30期9卷 9168-9173页

作者： Di wang jin-quan wang Xiao-Gen Tao Department of Intensive Care Medicine The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230036Anhui ProvinceChina

BACKGROUND Visceral disseminated varicella-zoster virus(VZV)infection is a rare but lifethreatening *** transplant recipients with VZV infection,visceral dissemination may develop without skin eruptions,which leads to the failure of early *** SUMMARY The patient was a 33-year-old male renal recipient who was referred to our hospital with severe upper abdominal pain of 3-d *** admission,the patient rapidly developed septic shock and multiple organ dysfunction syndrome with liver dysfunction and acute kidney ***-generation sequencing of peripheral blood yielded 39224 sequence reads of VZV,and real-time polymerase chain reaction for VZV was positive,with 1.2×10^(7) copies/*** final diagnosis was visceral disseminated VZV *** and supportive therapy were started,but the patient died of severe visceral organ damage 16 h after *** Visceral disseminated VZV infection is possible in renal transplant recipients presenting abdominal pain and rapidly-evolving organ damage without skin involvement.

关键词： Septic shock Visceral disseminated infection Renal transplantation Next-generation sequencing Multiple organ failure Case report

Strong shock propagation for the finite-source circular blast in a confined domain

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1071-1084页

作者： Qihang MA Kaileong CHONG Bofu wang quan ZHOU Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible *** reflection of the primary shock and its propagation within a confined domain are studied both theoretically and numerically in this *** the assumption of strong shock,the scaling law governing propagation of the main shock is *** dimensionless frequency of reflected shock propagation is associated with the confined *** numerical simulation for the circular explosion problem in a confined domain is performed for *** the influence of confinement,the principal shock wave systematically undergoes reflection within the domain until it weakens,leading to the non-monotonic attenuation of kinetic energy in the explosion fireball and periodic oscillations of the fireball volume with a certain *** simulation results indicate that the frequency of kinetic energy attenuation and the volume oscillation of the explosive fireball align consistently with the scaling law.

关键词： explosion confinement main shock frequency

High-resolution neutronics model for ^(238)Pu production in high-flux reactors

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Nuclear Science and Techniques 2024年第5期35卷 226-236页

作者： Qing-quan Pan Qing-Fei Zhao Lian-Jie wang Bang-Yang Xia Yun Cai jin-Biao Xiong Xiao-jing Liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux *** filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy *** burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme *** three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were *** neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.

关键词： ^(238)Pu Neutronics model High-flux reactor Spectrum resolution Spectrum optimization

A Bregman-Style Improved ADMM and its Linearized Version in the Nonconvex Setting:Convergence and Rate Analyses

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Journal of the Operations Research Society of China 2024年第2期12卷 298-340页

作者： Peng-Jie Liu jin-Bao Jian Hu Shao Xiao-quan wang Jia-Wei Xu Xiao-Yu Wu School of Mathematics Jiangsu Center for Applied MathematicsChina University of Mining and TechnologyXuzhou 221116JiangsuChina School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006GuangxiChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina

This work explores a family of two-block nonconvex optimization problems subject to linear *** first introduce a simple but universal Bregman-style improved alternating direction method of multipliers(ADMM)based on the iteration framework of ADMM and the Bregman ***,we utilize the smooth performance of one of the components to develop a linearized version of *** to the traditional ADMM,both proposed methods integrate a convex combination strategy into the multiplier update *** each proposed method,we demonstrate the convergence of the entire iteration sequence to a unique critical point of the augmented Lagrangian function utilizing the powerful Kurdyka–Łojasiewicz property,and we also derive convergence rates for both the sequence of merit function values and the iteration ***,some numerical results show that the proposed methods are effective and encouraging for the Lasso model.

关键词： Nonconvex optimization Alternating direction method of multipliers:Kurdyka-Lojasiewicz property.Convergence rate

Hydrocarbon accumulation principles in troughs within faulted depressions and their significance in exploration

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Petroleum Science 2011年第1期8卷 1-10页

作者： Zhao Xianzheng jin Fengming wang quan Lu Xuejun Huabei Oilfield Company PetroChinaHebei 062552China

Previously,troughs in continental faulted depressions were usually considered as a zone of hydrocarbon generation and expulsion rather than a zone for hydrocarbon *** they were confirmed to be the source kitchen,the possibility that they could constitute potential plays would be overlooked in the subsequent exploration *** on the hydrocarbon exploration practice of the Jizhong Depression and the Erlian Basin in the past several years,this paper discusses a new understanding that reservoir distribution is controlled by multiple factors and lithological accumulations are more likely to form in trough *** further documents the three main factors controlling the formation of large lithological hydrocarbon accumulations in trough *** paper also discusses the new concept that structural and lithological accumulations not only co-exist but also complement each *** propose that fan-delta fronts on inverted steep slopes in troughs,delta fronts and sublacustrine fans on gentle slopes,channel sands along toes of fault scarps are favorable locations for discovery of new oil *** application of this concept has led to the discovery of several hundreds of million tonnes of oil in place in trough areas in the Jizhong Depression and the Erlian Basin.

关键词： Sand distribution multiple controlling factors preferential hydrocarbon accumulation accumulation in troughs accumulation model exploration method

Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang Wen-Qing wang Jia-Ping Lin Li-quan wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics