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Theoretical insights of the pharmaceutical compound fluoxetine in water:Role in direct photolysis and indirect photolysis by free radicals

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Journal of Environmental Sciences 2024年第8期142卷 269-278页

作者： Ying lu Se Wang Yifan shen School of Environmental Science and Engineering Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyJiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlNanjing University of Information Science and TechnologyNanjing 210044China

The frequent detection of pharmaceutical compounds in the environment has led to a growing awareness,which may pose a major threat to the aquatic *** this study,photodegradation(direct and indirect photolysis)of two different dissociation states of fluoxetine(Flu)was investigated in water,mainly including the determination of photolytic transition states and products,and the mechanisms of indirect photodegradation with·OH,CO_(3)^(*-)and NO_(3)^(*).The main direct photolysis pathways are defluorination and C–C bond *** addition,the indirect photodegradation of Flu in water is mainly through the reactions with·OH and NO_(3)^(*),and the photodegradation reaction with CO_(3)^(*-)is relatively difficult to occur in the water *** results provide a theoretical basis for understanding the phototransformation process of Flu in the water environment and assessing its potential risk.

关键词： Fluoxetine Photochemical mechanism Direct photolysis Free radical reaction DFT

Recent Advances in Enantioselective Reactions of Terminal Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第7期42卷 760-776页

作者： Qihang Guo Xuzhong shen Zhan lu Centerof ChemistryforFrontier Technologies Departmentof ChemistryZhejiang UniversityHangzhouZhejiang 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center HangzhouZhejiang 311215China College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China

α-Olefins as aliphatic terminal alkenes could be obtained easily from numerous contemporary synthetic reactions as well as petro-chemical industry,and also found in natural *** to the alkenes attaching the directing groups or activating group,the catalytic asymmetric reaction of unactivated terminal alkenes presents great challenges due to the weak electron effect and small steric hindrance *** review mainly summarizes the latest progress of the asymmetric reaction of unactivated terminal olefins since 2016.

关键词： Asymmetric catalysis Terminal unactivated alkenes Hydrofunctionalization Difunctionalization Metal-catalyzed

Large reversible magnetocaloric effect in antiferromagnetic Er_(3)Si_(2)C_(2) compound

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Journal of Rare Earths 2024年第8期42卷 1555-1559,I0005页

作者： Hao Sun lu Tian Xinqiang Gao Zhaojun Mo Jun shen Baogen shen School of Rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China Department of Energy and Power Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

The magnetic properties,magnetic phase transition and magnetocaloric effects(MCE) of Er_(3)Si_(2)C_(2) compound were investigated based on theoretical calculations and experimental *** on the first principles calculations,the antiferromagnetic(AFM) ground state type in Er_(3)Si_(2)C_(2) compound was predicted and its electronic structure was *** experimental results show that Ei_(3)Si_(2)C_(2) compound is an AFM compound with the Neel temperature(T_(N) of 7 K and undergoes a field-induced firstorder magnetic phase transition from AFM to ferromagnetic(FM) under magnetic fields exceeding 0.6 T at 2 *** magnetic transition process of Er_(3)Si_(2)C_(2) compound was investigated and *** values of the maximum magnetic entropy change(-ΔS_(M)^(max)) and the refrigeration capacity(RC) are 17 J/(kg·K)and 193 J/kg under changing magnetic fields of 0-5 T,*** a potential cryogenic magnetic refrigerant,the Er_(3)Si_(2)C_(2) compound also provides an interesting research medium to study the magnetic phase transition process.

关键词： Magnetic materials Magnetocaloric Metamagnetic transitions Magnetic phase transition Rare earths

Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter Communication System

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China Communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang ting Li Yin lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

A toroidal SAW gyroscope with focused IDTs for sensitivity enhancement

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Microsystems & Nanoengineering 2024年第2期10卷 47-56页

作者： lu Tian Haitao Zhao Qiang shen Honglong Chang Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an710072China

A surface acoustic wave(SAW)gyroscope measures the rate of rotational angular velocity by exploiting a phenomenon known as the SAW gyroscope *** a gyroscope is a great candidate for application in harsh environments because of the simplification of the suspension vibration mechanism necessary for traditional microelectromechanical system(MEMS)***,for the first time,we propose a novel toroidal standing-wave-mode SAW gyroscope using focused interdigitated transducers(FIDTs).Unlike traditional SAW gyroscopes that use linear IDTs to generate surface acoustic waves,which cause beam deflection and result in energy dissipation,this study uses FIDTs to concentrate the SAW energy based on structural features,resulting in better focusing performance and increased SAW *** experimental results reveal that the sensitivity of the structure is 1.51µV/(°/s),and the bias instability is 0.77°/s,which are improved by an order of magnitude compared to those of a traditional SAW ***,the FIDT component can enhance the performance of the SAW gyroscope,demonstrating its superiority for angular velocity *** work provides new insights into improving the sensitivity and performance of SAW gyroscopes.

关键词： angular deflection gyroscope

G protein-coupled receptors(GPCRs):advances in structures,mechanisms,and drug discovery

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1938-1980页

作者： Mingyang Zhang ting Chen Xun lu Xiaobing Lan Ziqiang Chen Shaoyong lu Key Laboratory of Protection Development and Utilization of Medicinal Resources in Liupanshan AreaMinistry of EducationPeptide&Protein Drug Research CenterSchool of PharmacyNingxia Medical UniversityYinchuan 750004China Medicinal Chemistry and Bioinformatics Center Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Cardiology Changzheng HospitalAffiliated to Naval Medical UniversityShanghai 200003China Department of Orthopedics Changhai HospitalAffiliated to Naval Medical UniversityShanghai 200433China

G protein-coupled receptors(GPCRs),the largest family of human membrane proteins and an important class of drug targets,play a role in maintaining numerous physiological *** or antagonist,orthosteric effects or allosteric effects,and biased signaling or balanced signaling,characterize the complexity of GPCR dynamic *** this study,we first review the structural advancements,activation mechanisms,and functional diversity of *** then focus on GPCR drug discovery by revealing the detailed drug-target interactions and the underlying mechanisms of orthosteric drugs approved by the US Food and Drug Administration in the past five ***,an up-to-date analysis is performed on available GPCR structures complexed with synthetic small-molecule allosteric modulators to elucidate key receptor-ligand interactions and allosteric ***,we highlight how the widespread GPCR-druggable allosteric sites can guide structure-or mechanism-based drug design and propose prospects of designing bitopic ligands for the future therapeutic potential of targeting this receptor family.

关键词： steric designing mechanisms

A two-pronged strategy utilizing exosomes extracted from antigenpresenting cells to combat hepatitis B

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Nano Research 2024年第10期17卷 9084-9094页

作者： Fumin Hu Dangyang Wang ting lu Guanghui Ma Hua Yue State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBeijing 100190China

Chronic hepatitis B(CHB)is consistently challenging to conquer with numerous complications and *** the effectiveness of antiviral therapies in suppressing hepatitis B virus(HBV)replication,there is an urgent need for novel and more effective treatment *** strategies predominantly emphasize immune activation but still face challenges in sufficiently eliciting T cell *** into account the targeted delivery of nanoparticles to the liver and spleen via intravenous injection,we have proposed a dual-pronged therapeutic strategy based on antigen-presenting cells(APCs)-derived ***,exosomes targeted to the spleen can activate specific immune responses,while those targeted to the liver can modulate or reverse the liver’s immunosuppressive *** immunization,exosome formulations exhibit the remarkable ability to effectively activate APCs,thereby triggering the proliferation of CD8^(+)T ***,they also play an immunoregulatory role by converting M2 macrophages into M1 *** two-pronged therapeutic strategy precisely addresses the issues of T cell dysfunction and immune suppression,both characteristic features of CHB *** combined with Aluminum(Alum)-adjuvanted vaccine,these exosome formulations not only demonstrate a high level of cellular immune response but also secrete specific antibodies comparable to those induced by Alum *** combined approach effectively enhances both cellular and humoral immunity,offering a promising avenue for the development of therapeutic hepatitis B vaccines based on exosome formulations.

关键词： chronic hepatitis B antigen-presenting cells(APCs)-derived exosomes immunoregulatory role two-pronged therapeutic strategy

Aggregation-regulated bioreduction process of graphene oxide by Shewanella bacteria

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Chinese Journal of Chemical Engineering 2024年第5期69卷 56-62页

作者： Kaixin Han Yibo Zeng Yinghua lu Ping Zeng Liang shen Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Chinese Research Academy of Environmental Sciences Beijing 100012China

The bioreduction of graphene oxide(GO)using environmentally functional bacteria such as Shewanella represents a green approach to produce reduced graphene oxide(rGO).This process differs from the chemical reduction that involves instantaneous molecular *** bioreduction,the contact of bacterial cells and GO is considered the rate-limiting *** reveal how the bacteria-GO integration regulates rGO production,the comparative experiments of GO and three Shewanella strains were carried ***-transform infrared spectroscopy,X-ray photoelectron spectroscopy,Raman spectroscopy,and atomic force microscopy were used to characterize the reduction degree and the aggregation *** results showed that a spontaneous aggregation of GO and Shewanella into the condensed entity occurred within 36 h.A positive linear correlation was established,linking three indexes of the aggregation potential,the bacterial reduction ability,and the reduction degree(ID/IG)comprehensively.

关键词： Graphene oxide Reduced graphene oxide Bioreduction Aggregation Shewanella

Study of factors influencing the occurrence rate of 60 Hz power line radiation in the topside ionosphere:A systematic survey using the CSES satellite

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Science China(Technological Sciences) 2024年第6期67卷 1879-1892页

作者： MA ZhenHui ZHAO ShuFan LIAO Li shen XuHui lu HengXin School of Emergency Management Science and Engineering University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing100190China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing100190China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Institute of Geophysics China Earthquake AdministrationBeijing100081China

We analyze the topside ionosphere power line radiation(PLR)at 60 Hz over the US using electric field data collected by CSES satellite between January 2019 and December *** study aimed to further investigate the month-to-month variation characteristic of PLR occurrence rate observed by satellite and its several influencing factors,including solar radiation,lightning activity,and try to clarify the influence of electricity *** results show that the solar radiation(solar zenith angle and F10.7)plays a major role in the variation of the PLR occurrence rate,and that there is no direct connection with the number of *** the relationship between PLR occurrence rate and electricity consumption,the low occurrence rate associated with decreased weekend electricity consumption was not observed in the ***,there is a significant difference in PLR occurrence rate between the East and West Coasts of the US at the same latitude during the same time period,suggesting that the significant difference in PLR occurrence rate is caused by the significant difference in electricity consumption between the two *** excluding the effect of solar radiation on PLR occurrence rate,we concluded that only a significant difference in regional electricity consumption could lead to a corresponding change in PLR occurrence rate detected by the Low-Earth-Orbit ***,we also found there is seasonal variation in the diurnal differences of the PLR occurrence rate caused by seasonal variation of the lower ionosphere.

关键词： CSES satellite power line radiation occurrence rate solar radiation lightning activity electricity consumption