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Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin dong-sheng ji Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

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Coordination for a Closed-loop Supply Chain with Recycling Platform Considering Dynamic Setting

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 425-451页

作者： Zehua Xiang Ting ji Lingfeng dong School of Management Zhejiang UniversityHangzhou310058China School of Business Hangzhou City UniversityHangzhou310015China Alibaba Business College Hangzhou Normal UniversityHangzhou311121China

This paper presents a dynamic closed-loop supply chain(CLSC)model,incorporating a manufacturer,a retailer,and an internet recycling platform(IRP),utilizing differential game theory while considering the forgetting effect of *** model encompasses factors such as the quality level of used products and Big Data marketing(BDM),comparing optimal equilibriums under decentralized and cooperative decision *** effectively coordinate the dynamic CLSC at each time point,we propose a revenue-sharing and cost-sharing(RSCS)combined *** addition to ensuring reasonable sharing of revenues and costs,this contract allows the manufacturer to flexibly adjust wholesale prices for final products and transfer prices for used products in order to distribute profits appropriately and achieve Pareto optimality within the CLSC ***,our results indicate that there exists a threshold for Big Data marketing efficiency;high-efficiency BDM not only facilitates increased recycling on Internet platforms but also reduces unit recycling costs for ***,when implementing the combined contract,Big Data marketing efficiency does not impact the transfer price paid by manufacturers to Internet recycling platforms.

关键词： Big Data marketing differential game closed-loop supply chain coordination internet recycling platform

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Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 4-13页

作者： ji-Yao sheng Zi-Fan Meng Qiao Li Yong-sheng Yang Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun 130041China jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases the Second Hospital of Jilin UniversityChangchun 130041China

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with *** primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related *** recent advances in precision medicine,precise drug treatment provides better treatment *** sources:Literature search was conducted in PubMed,MEDLINE and Web of Science for relevant articles published up to May *** on clinical trials was obtained from https://***/and http://***/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising *** to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and *** these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal ***:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

关键词： Cirrhotic portal hypertension Target drug Primary prevention Bleeding

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Surface engineering of Li-and Mn-rich layered oxides for superior Li-ion battery

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Tungsten 2024年第1期6卷 259-268页

作者： Lu-Xiang Ma Tian-dong Chen Chun-Xi Hai sheng-De dong Xin He Qi Xu Hang Feng AXin ji-Tao Chen Yuan Zhou College of Materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChendu 610000China Qinghai Building and Materials Research Co. LtdXining 810000China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The Li-and Mn-rich layered oxides(R-LNCM)are considered as promising cathode materials for high-energy density lithium-ion batteries(LIBs).However,the interface side reaction aggravates the voltage and capacity fading between cathode material and electrolyte at high voltage,which severely hinders the practical application of LIB ***,lithium polyacrylate(LiPAA)as the binder and coating agent is applied to suppress the voltage and capacity fading of R-LNCM *** flexible LiPAA layers with high elasticity are capable of impeding cathode cracks on the particle surface via mechanical stress ***,superior voltage and capacity fading suppression on R-LNCM electrode is finally *** a result,LiPAA-R-LNCM cathode exhibits a remarkable specific capacity of 186 mA·h·g^(-1)with~73%retention at 1℃after ***,the corresponding average discharge potential is maintained to~3.1 V with only~0.4 V falling.

关键词： LiPAA interphase layer Interface side reaction Cathode cracks Capacity and voltage fading suppression Liand Mn-rich cathode

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High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu Liu Tian-Yi ji Yang Li Da-Wei sheng Shao-dong Li Pei-Pei Ren Ze-Xiang Shen School of Material Science and Engineering Shaanxi University of Science and Technology School of Physical and Mathematical Sciences Nanyang Technological University

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone（ZIF） and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber（CoP@CF） were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g-1at 0.1 A·g-1after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g-1at 0.1 A·g-1after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·*** sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Free-standing anodes Sodium-ion batteries

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Applying dynamic light scattering to investigate the self-assembly process of DNA nanostructures

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Chinese Chemical Letters 2024年第3期35卷 316-320页

作者： Wei Yuan Gui-Zhi dong Hui Ning Xiang-Xiang Guan jia-Feng Cheng Zi-Wei Shi Xiu-ji Du Si-Wen Meng dong-sheng Liu Yuan-Chen dong CAS Key Laboratory of Colloid Interface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dandong Bettersize Instruments Ltd. Dandong 118000China Key Laboratory of Organic Optoelectronics&Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Department of Chemistry Renmin University of ChinaBeijing 100872China

Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional *** this work,temperature-controlled dynamic light scattering(DLS)strategy has been applied to study the global assembly process of DNA origami and DNA *** the temperature dependent size and intensity profiles,the self-assembly process of various DNA nanostructures with different morphologies have been well-studied and the temperature transition ranges could be *** advantage of the DLS information,rapid preparation of the DNA origami and the brick assembly has been realized through a constant temperature *** results demonstrate that the DLS-based strategy provides a convenient and robust tool to study the dynamic process of forming hieratical DNA structures,which will benefit understanding the mechanism of self-assembly of DNA nanostructures.

关键词： Dynamic light scattering Self-assembly process DNA nanostructures Temperature transition ranges Rapid preparation

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Nuclearity and Finite-Representability in the System of Completely Integral Mapping Spaces

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1197-1214页

作者： Zhe dong ji Cheng TAO Ya Fei ZHAO Department of Mathematics Zhejiang UniversityHangzhou 310027P.R.China Department of Mathematics China Jiliang UniversityHangzhou 310018P.R.China Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023P.R.China

In this paper,we investigate local properties in the system of completely integral mapping *** introduce notions of injectivity,local reflexivity,exactness,nuclearity,finite-represent ability and WEP in the system of completely integral mapping *** we obtain that any finite-dimensional operator space is injective in the system of completely integral mapping *** we prove that C is the unique nuclear operator space and the unique exact operator space in this *** also show that C is the unique operator space which is finitely representable in{T_(n)}n∈Nin this *** corollaries,Kirchberg’s conjecture and QWEP conjecture in the system of completely integral mapping spaces are false.

关键词： Completely integral mapping space injectivity exactness nuclearity finite-representability WEP

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Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： Chen Yang Qiao-sheng Xia Cun-Hong Yin dong-Peng Hua College of Mechanical Engineering Guizhou University Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou University State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical University

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy（PMPEA） exhibits excellent mechanical and tribological ***,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of *** this study,the FeCoNi/Ni3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics（MD） simulation were *** results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the *** is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces *** particular,the deformation behavior of Ni3Ti lamellae changes from crystal-like to amorphous-like with decreasing ***,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic（BCC） phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing *** the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch

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Metal-free Optical Pressure Sensor with High Sensitivity and Extensive Range

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1291-1300页

作者： Mao ji Meng Huang Haomin Lyu sheng Shi Bo Qi Chengrong Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China IEEE CSEE

Pressure monitoring of a transformer oil tank can grasp the pressure change process caused by gas production when severe internal defects occur and take timely measures to ensure the safe operation of the *** pressure sensors generally use metal encapsulation or have an air cavity structure,threatening the transformer’s insulation if it is directly used inside the *** this end,this paper proposes a method for developing a high-sensitivity,large-range,and metallizationfree optical pressure sensing device with temperature *** grating is encapsulated by fluorosilicone rubber and supplemented by an epoxy resin shielding shell on the *** the same time,a double-grating vertical arrangement is adopted to improve pressure measurement sensitivity,further avoiding the influence of temperature rise caused by a defect of the transformer on the measurement result of the *** addition,by optimizing the geometric structure of the internal sensitizing element,pre-stretching length of the fiber grating,gap distance,and other parameters,probe size can be reduced while ensuring the sensor’s *** show the proposed method can meet the requirements of sensor fabrication with different sensitivities and ranges,and to a certain extent,both high sensitivity and extensive ranges can be taken into *** sensitivity of the fabricated prototype is 15 pm/kPa,and the range is about 0.2 *** the same time,the metal-free feature of the sensor makes it suitable for use in various oil-immersed power *** records oil pressure changes caused by oil discharge breakdown,making it sensitive to small pressure changes in early failures.

关键词： Highly sensitive extensive range optical sensing no metallization pressure perception temperature compensation transformer

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Joint Probability Analysis and Prediction of Sea Ice Conditions in Liaodong Bay

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Journal of Ocean University of China 2024年第1期23卷 57-68页

作者： LIAO Zhenkun dong sheng TAO Shanshan HUA Yunfei jiA Ning College of Engineering Ocean University of ChinaQingdao 266100China Shuifa Planning and Design Co. Ltd.Jinan 250100China National Hazards Mitigation Service Beijing 100194China

Sea ice conditions in Liaodong Bay of China are often described by sea ice grades,which classify annual sea ice conditions based on the annual maximum sea ice thickness(AM-SIT)and annual maximum floating ice extent(AM-FIE).The joint probability distribution of AM-SIT and AM-FIE was established on the basis of their data pairs from 1949/1950 to 2019/2020 in Liaodong *** joint intensity index of the sea ice condition in the current year is calculated,and the joint classification criteria of the sea ice grades in past years are established on the basis of the joint intensity index series.A comparison of the joint criteria with the 1973 and 2022 criteria revealed that the joint criteria of the sea ice grade match well,and the joint intensity index can be used to quantify the sea ice condition over the years.A time series analysis of the sea ice grades and the joint intensity index sequences based on the joint criteria are then *** show a decreasing trend of the sea ice condition from 1949/1950 to 2019/2020,a mutation in 1990/1991,and a period of approximately 91 years of the sea ice *** addition,the Gray-Markov model(GMM)is applied to predict the joint sea ice grade and the joint intensity index of the sea ice condition series in future years,and the error between the results and the actual sea ice condition in 2020/2021 is small.

关键词： sea ice grade ice thickness floating ice extent Liaodong Bay copula

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