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Modular Synthesis of Multi-substituted Cyclobutanones Enabled by Oxyallyl Cations

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Chinese Journal of Chemistry 2024年第5期42卷 459-463页

作者： Meng Wang Zhonggui Wang ping lu Research Center for Molecular Recognition and Synthesis Department of ChemistryFudan University220 Handan LuShanghai200433 China Present address: Department of Cancer Biology Dana-Farber Cancer Institute Department of Biological Chemistry and Molecular Pharmacology Harvard Medical SchoolBostonMA 02115USA

Stereoselective synthesis of multi-substituted cyclobutanes with different substituents is still a daunting challenge in organic *** report here a practical and facile approach to synthesizing all-trans 2,3,4-trisubstituted cyclobutanones from readily available *** substitution reaction proceeds smoothly via oxyallyl cation intermediates under mild basic *** transformation to the synthesis of 1,2,3,4-tetrasubstituted cyclobutanes was also explored.

关键词： Diastereoselectivity Modular synthesis Nucleophilic substitution Organohalides Oxyallyl cation Precision functionalization Strained molecules 1,2,3,4-Tetrasubstituted cyclobutanes

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Petroleum Science 2024年第4期21卷 2383-2392页

作者： Li-Ming Zhao Cai-ping lu Yang Liu Chao-Chao Li School of Mines China University of Mining and Technology Henan Institute of Geophysical Space Information

The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D) poroelastic model and the layered White model were investigated. This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale. For the inherent mechanism, both models resulted from quasi-static flow in a slow P-wave diffusion mode, and the differences between them originated from saturated fluids and boundary conditions. On the other hand, for the characteristic frequencies of the models, the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model. Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length. The differences between them were due to the diffusion length. The diffusion length for the 1D poroelastic model was determined by the sample length, whereas that for the layered White model was determined by the length of the representative elementary volume(REV). Subsequently, a numerical example was presented to demonstrate the similarities and differences between the models. Finally, published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole *** prediction of the combined model was in good agreement with the experimental data, thereby validating the effectiveness of the 1D poroelastic model. Furthermore, the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction, validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model. The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus d

关键词： 1D poroelastic model Layered White model Quasi-static flow Slow P-wave diffusion Characteristic frequency Diffusion length

Advancements in S-scheme heterojunction materials for photocatalytic environmental remediation

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Journal of Materials Science & Technology 2024年第2期169卷 182-198页

作者： Changliang Nie Xiaohan Wang ping lu Yukun Zhu Xin Li Hua Tang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao266071China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China School of Environmental Science and Engineering Shandong UniversityQingdao266237China

Recently,S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox ***,this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental *** review first covers the fundamentals of heterogeneous photocatalysis for environmental ***,an introduction to the background,mechanism,design principles,and characterization techniques of S-scheme heterojunctions is ***,the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants,such as bacteria,heavy metals,nitrogen oxides,antibiotics,and ***,the modification strategies of S-scheme heterojunction photocatalysts are also ***,a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

关键词： S-scheme heterojunctions Photocatalyst Pollutant Environmental remediation

Beamline design for multipurpose muon beams at CSNS EMuS

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Nuclear Science and Techniques 2024年第5期35卷 1-12页

作者： Yang Hong Ying-Peng Song lu-ping Zhou Jing-Yu Tang Zhi-Hao Zhou Nikolaos Vassilopoulos Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China Radiotherapy Physics and Technology Center Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China Xi’an Jiaotong University Health Science Center Xi’an 710049China Department of Radiation Oncology First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710049China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China

A new muon beam facility,called the Experimental Muon Source(EMuS),was proposed for construction at the China Spallation Neutron Source(CSNS).The design of the complex muon beamlines for the EMuS baseline scheme,which is based on superconducting solenoids,superferric dipoles and room-temperature magnets,is presented *** muon beams,including surface muons,decay muons and low energy muons,have been developed for multipurpose *** optics design and simulation results of the trunk beamline and branch beamlines are *** a proton beam power of 25 kW at a standalone target station that consists of a conical graphite target and high-field superconducting solenoids,the muon beam intensity in the trunk beamline varies from 10^(7)/s for surface muons to 10^(10)/s for high-momentum decay *** at the endstations,these values vary from 10^(5)/s for surface muons to 10^(8)/s for decay muons.

关键词： Surface muons Decay muons Muon beamline Superconducting solenoids Multi-channel electrostatic separator

Phase field modeling of grain stability of nanocrystalline alloys by explicitly incorporating mismatch strain

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Rare Metals 2024年第7期43卷 3370-3382页

作者： Min Zhou Hong-Hui Wu Yuan Wu Hui Wang Xiong-Jun Liu Sui-He Jiang Xiao-Bin Zhang Zhao-ping lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083Cnina Institute for Carbon Neutrality University of Science and TechnologyBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Ab st ra ct Nanocrystalline materials exhibit unique properties due to their extremely high grain boundary(GB) ***,this high-density characteristic induces grain coarsening at elevated temperatures,thereby limiting the widespread application of nanocrystalline *** experimental observations revealed that GB segregation and second-phase pinning effectively hinder GB migration,thereby improving the stability of nanocry stalline *** this study,a mouified phase-field model that integrates mismatch strain,solute segregation and precipitation was developed to evaluate the influence of lattice misfit on the thermal stability of nanocrystalline *** simulation results indicated that introducing a suitable mismatch strain can effectively enhance the microstructural stability of nanocrystalline *** synergizing precipitation with an appropriate lattice misfit,the formation of second-phase particles in the bulk grains can be suppressed,thereby facilitating solute segregation/precipitation at the *** concentrated solute segregation and precipitation at the GBs effectively hinders grain migration,thereby preventing grain *** findings provide a new perspective on the design and regulation of nanocrystalline alloys with enhanced thermal stability.

关键词： Phase field model Mismatch strain Second-phase precipitation Grain boundary segregation Nanocrystalline alloys

Innovative Mn3-xO4-y@NCA design:Leveraging Mn/O vacancies and amorphous architecture for enhanced sodium-ion storage

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Journal of Energy Chemistry 2024年第10期97卷 747-756页

作者： Kaijun Xie Xin Liu Kai Xia Lipeng Diao ping lu Mengmeng Wang Long Fang Yihui Zou Dongjiang Yang Xiaodong Zhang College of Chemistry and Chemical Engineering College of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textiles Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological Textiles Institute of Marine Biobased Materials Qingdao University Institute of Micro/Nano Materials and Devices Ningbo University of Technology

Manganese-based oxide electrode materials suffer from severe Jahn-Teller（J-T） distortion,leading to severe cycle instability in sodium ion ***,it is difficult to adjust the electron at d orbitals exactly to a low spin state to eliminate orbital degeneracy and suppress J-T distortion *** article constructed concentration-controllable Mn/O coupled vacancy and amorphous network in Mn3O4and coated it with nitrogen-doped carbon aerogel(Mn3-xO4-y@NCA).The existence of Mn/O vacancies has been confirmed by scanning transmission electron microscopy（STEM） and positron annihilation lifetime spectroscopy（PALS）.Atomic absorption spectroscopy（AAS） and X-ray photoelectron spectroscopy（XPS） determine the most optimal ratio of Mn/O vacancies for sodium ion storage is 1:*** functional theory（DFT） calculations prove that Mn/O coupled vacancies with the ratio of 1:2could exactly induce a low spin states and a d4electron configuration of Mn,suppressing the J-T distortion *** abundant amorphous regions can shorten the transport distance of sodium ions,increase the electrochemically active sites and improve the pseudocapacitance *** the synergetic effect of Mn/O coupled vacancies and amorphous regions,Mn3-xO4-y@NCA exhibits an energy density of 37.5 W h kg-1and an ultra-high power density of 563 W kg-1in an asymmetric *** sodium-ion batteries,it demonstrates high reversible capacity and exceptional cycling *** research presents a new method to improve the Na+storage performance in manganese-based oxide,which is expected to be generalized to other structural distortion.

关键词： Amorphous network Concentration-controllable Mn/O coupled vacancies Manganese-based metal oxide Sodium ion battery Sodium ion supercapacitor

Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model

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Research in Astronomy and Astrophysics 2024年第4期24卷 271-286页

作者： Yong-Xiong Zhang Wen-Xiu Guo Xiao-ping lu Hua Zheng Hai-Bin Zhao Jun Tian Wei-Lin Wang School of Engineering Guangzhou College of Technology and BusinessGuangzhou 510850China School of Computer Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China School of Mathematics and Statistics Shaoguan UniversityShaoguan 512099China State Key Laboratory of lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryCASNanjing 210023China

Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally *** paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate *** PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore *** PDE algorithm accurately derives period and pole values from simulated *** analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole *** PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data *** work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.

关键词： methods:numerical minor planets asteroids:general techniques:photometric astrom

Efficacy of transjugular intrahepatic portosystemic shunts in treating cirrhotic esophageal-gastric variceal bleeding

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 471-480页

作者： Xiao-Gang Hu Jian-Ji Dai Jun lu Gang Li Jia-Min Wang Yi Deng Rui Feng Kai-ping lu Department of Interventional Radiology The Affiliated Jinhua HospitalZhejiang University School of MedicineJinhua 321000Zhejiang ProvinceChina Department of Interventional Medicine Zhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina Department of Vascular Surgery Zhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Esophageal-gastric variceal bleeding(EGVB)represents a severe complication among patients with cirrhosis and often culminates in fatal ***-tional therapy,a rapidly developing treatment modality over the past few years,has found widespread application in clinical practice due to its minimally inva-sive ***,whether transjugular intrahepatic portosystemic shunt(TIPS)treatment has an impact on patient prognosis remains *** A retrospective study was conducted on ninety-two patients presenting with cirrhotic EGVB who were admitted to our hospital between September 2020 and September *** on the different modes of treatment,the patients were assigned to the study group(TIPS received,n=50)or the control group(per-cutaneous transhepatic varices embolization received,n=42).Comparative ana-lyses were performed between the two groups preoperatively and one month postoperatively for the following parameters:Varicosity status;hemodynamic parameters[portal vein flow velocity(PVV)and portal vein diameter(PVD);platelet count(PLT);red blood cell count;white blood cell count(WBC);and hepatic function[albumin(ALB),total bilirubin(TBIL),and aspartate transaminase(AST)].The Generic Quality of Life Inventory-74 was utilized to assess quality of life in the two groups,and the 1-year postoperative rebleeding and survival rates were *** Following surgical intervention,there was an improvement in the incidence of varicosity compared to the preoperative status in both ***,the study group exhibited more pronounced enhancements than did the control group(Plues,with the study cohort achieving better outcomes(P<0.05).PLT and WBC counts were elevated postoperatively in the two groups,with the study cohort displaying higher PLT and WBC counts(P<0.05).No differences were detected between the two groups in terms of serum ALB,TBIL,or AST lev

关键词： Liver cirrhosis Esophagogastric variceal bleeding Transjugular intrahepatic portosystemic shunt Prognosis

Study on the Correlation between Metabolic Syndrome and Colorectal

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Journal of Biosciences and Medicines 2024年第7期12卷 9-16页

作者： Jin Wei ping lu Department of Gastroenterology Jingzhou Hospital Affiliated to Yangtze University Jingzhou China

Metabolic syndrome has been widely recognized in various studies as being intricately linked to the initiation and progression of colorectal adenoma. The potential pathways through which metabolic syndrome influences colorectal adenoma encompass chronic inflammation, insulin resistance, oxidative stress, and dysbiosis of the intestinal flora. This review aims to consolidate the understanding of the association between metabolic syndrome and colorectal adenoma, elucidating the interconnected mechanisms between different metabolic syndrome-related disorders and colorectal adenoma. By shedding light on these connections, this review offers valuable insights for the preventive strategies targeting colorectal adenoma.

关键词： Metabolic Syndrome Obesity Hypertension Lipid Disorders Colorectal Adenoma Colorectal Cancer