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Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan Wei Jiang Chuan Yue Shi-Jun Lei Yu-xin Cui Qiang yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Heat management technology for solid-state high voltage and high repetitive pulse generators:Towards better effects and reliability

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High Voltage 2024年第1期9卷 2-21页

作者： Yanan Wang Linyuan Ren Zihao Yang Saikang Shen Zichen deng Qi yuan Weidong Ding Zhenjie Ding School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina School of Electronic and Information Engineering Xi'an Jiaotong UniversityXi'anChina

Solid-state high voltage high repetitive pulse generators have a broad prospect in various *** high power and high-frequency operation of the pulse generator suffer from the massive heat dissipation problem,which limits the improvement of the output parameters and even affects the *** article focuses on heat management technology for high voltage high repetitive pulse ***,the typical circuit topology of the high repetitive pulse generators was *** the perspective of different application requirements,the demands of the heat management design were ***,the heat generation characteristics and difficulties of solid-state high voltage high repetitive pulse generators were ***,the different stateof-art cooling techniques were reviewed,and their applicability and limitations for the high voltage high repetitive generators were ***,a flow chart for heat management design was given.

关键词： pulse state high

Exploring treatment options in cancer: Tumor treatment strategies

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3337-3380页

作者： Beilei Liu Hongyu Zhou Licheng Tan Kin To Hugo Siu xin-yuan Guan Department of Clinical Oncology The University of Hong Kong-Shenzhen HospitalShenzhenChina Department of Clinical Oncology The University of Hong KongHong KongChina state Key Laboratory for Liver Research The University of Hong KongHong KongChina Advanced Energy Science and Technology Guangdong Laboratory HuizhouChina MOE Key Laboratory of Tumor Molecular Biology Jinan UniversityGuangzhouChina

Traditional therapeutic approaches such as chemotherapy and radiation therapy have burdened cancer patients with onerous physical and psychological ***,the landscape of tumor treatment has undergone a comprehensive and remarkable *** as fervently pursued modalities are small molecule targeted agents,antibody-drug conjugates(ADCs),cell-based therapies,and gene *** cutting-edge treatment modalities not only afford personalized and precise tumor targeting,but also provide patients with enhanced therapeutic comfort and the potential to impede disease ***,it is acknowledged that these therapeutic strategies still harbour untapped potential for further *** a comprehensive understanding of the merits and limitations of these treatment modalities holds the promise of offering novel perspectives for clinical practice and foundational research *** this review,we discussed the different treatment modalities,including small molecule targeted drugs,peptide drugs,antibody drugs,cell therapy,and gene *** will provide a detailed explanation of each method,addressing their status of development,clinical challenges,and potential *** aim is to assist clinicians and researchers in gaining a deeper understanding of these diverse treatment options,enabling them to carry out effective treatment and advance their research more effciently.

关键词： drugs treatment holds

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C_(6)F_(5))_(3)/chiral phosphoric acid

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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen Liu Zhi-yuan Ren Chen Yang Xiangyi Shao Li Chen xin Li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

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A review of covalent organic frameworks for metal ion fluorescence sensing

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Chinese Chemical Letters 2024年第8期35卷 74-83页

作者： Deshuai Zhen Chunlin Liu Qiuhui deng Shaoqi Zhang Ningman yuan Le Li Yu Liu Hunan Key Laboratory of Typical Environment Pollution and Health Hazards School of Public HealthHengyang Medical SchoolUniversity of South ChinaHengyang 421001China State Key Laboratory of Chemo/Biosensing and Chemometrics School of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

The concentration of metallic elements is closely associated with overall ***,the discharge of untreated industrial wastewater can lead to metal-containing pollutants entering the human body through the food chain,disrupting the organism’s homeostasis and posing a risk to human ***-valent organic framework materials(COFs)have emerged as a novel porous material for detecting or adsorbing metal ions due to their unique pore structure,topological structure and flexible *** paper summarizes the role,toxicity,and sources of metal ions related to human health,as well as the design,synthesis and performance of COFs fluorescent materials for detecting these *** inter-action mechanism of different fluorescent COFs and metal ions are ***,the remaining challenges and prospects of COFs fluorescence sensors are *** believe this review will be useful in directing the development of fluorescent COFs towards metal ions.

关键词： Covalent organic frameworks Metal ion Fluorescence Sensing Toxicity

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Restraining growth of Zn dendrites by poly dimethyl diallyl ammonium cations in aqueous electrolytes

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Rare Metals 2024年第8期43卷 3735-3747页

作者： Xiang-xin Zhang yuan-Qiang Chen Chang-xin Lin yuan-Sheng Lin Guo-Lin Hu Yong-Chuan Liu Xi-Lai Xue Su-Jing Chen Zhan-Lin Yang Bai-Sheng Sa Yi-Ning Zhang Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Helmholtz Institute Ulm(HIU) 89081 UlmGermany Karlsruhe Institute of Technology(KIT) 76021 KarlsruheGermany College of Materials Science and Engineering Fuzhou UniversityFuzhou350108China

Metallic zinc is an excellent anode material for Zn-ion batteries,but the growth of Zn dendrite severely hinders its practical ***,an efficient and economical cationic additive,poly dimethyl diallyl ammonium(PDDA) was reported,used in aqueous Zn-ion batteries electrolyte for stabilizing Zn *** growth of zinc dendrites can be significantly restrained by benefiting from the pronounced electrostatic shielding effect from PDDA on the Zn metal ***,the PDDA is preferentially absorbed on Zn(002) plane,thus preventing unwanted side reactions on Zn *** to the introduction of a certain amount of PDDA additive into the common ZnSO_(4)-based electrolyte,the cycle life of assembled Zn‖Zn cells(1 mA·cm^(-2) and 1 mAh·cm^(-2)) is prolonged to more than 1100 *** response to the perforation issue of Zn electrodes caused by PDDA additives,the problem can be solved by combining foamy copper with zinc *** real application,Zn-ion hybrid supercapacitors and MnO_(2)‖Zn cells were assembled,which exhibited excellent cycling stability with PDDA *** work provides a new solution and perspective to cope with the dendrite growth problem of Zn anode.

关键词： PDDA Electrostatic shielding effect Zn anode Zn dendrites

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Chemical Constituents and Pharmacological Properties of Frankincense:Implications for Anticancer Therapy

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Chinese Journal of Integrative Medicine 2024年第8期30卷 759-767页

作者： WU Yong-rong XIONG Wei DONG Ying-jing CHEN xin ZHONG yuan-yuan HE xin-ling WANG Yu-jia LIN Qun-fang TIAN Xue-fei ZHOU Qing College of Traditional Chinese Medicine Hunan University of Chinese MedicineChangsha410208China Department of Andrology the First Hospital of Hunan University of Chinese MedicineChangsha41007China College of Medicine Hunan University of Chinese MedicineChangsha410208China College of Traditional Chinese and Western Medicine Hunan University of Chinese MedicineChangsha410208China Hunan Provincial Key Laboratory of Traditional Chinese Medicine Prescription and Transformation Changsha410208China Hunan Sexual and Reproductive Health Clinical Medical Research Center of Traditional Chinese Medicine Changsha410021China

The discovery of novel antitumor agents derived from natural plants is a principal objective of anticancer drug ***,a widely recognized natural antitumor medicine,has undergone a systematic review encompassing its species,chemical constituents,and diverse pharmacological activities and *** different species of frankincense include Boswellia serrata,Somali frankincense,Boswellia frereana,and Boswellia *** frankincense extracts and compounds exhibit antitumor,anti-inflammatory,and hepatoprotective properties and antioxidation,memory enhancement,and immunological regulation *** also have comprehensive effects on regulating *** and its principal chemical constituents have demonstrated promising chemoprophylactic and therapeutic abilities against *** review provides a systematic summary of the mechanism of action underlying the antitumor effects of frankincense and its major constituents,thus laying the foundations for developing effective tumor-combating targets.

关键词： frankincense species chemical constituents anticancer therapy Chinesemedicine

Bearing mechanism of roof and rib support structure in automatically formed roadway and its support design method

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Journal of Central South University 2024年第7期31卷 2467-2487页

作者： JIANG Bei WANG Ming-zi WANG Qi xin Zhong-xin xinG Xue-yang deng Yu-song YAO Liang-di State Key Laboratory for Tunnel Engineering China University of Mining and Technology-BeijingBeijing 100083China Research Center of Geotechnical and Structural Engineering Shandong UniversityJi􀆳nan 250061China College of Civil Engineering and Architecture Shandong University of AeronauticsBinzhou 256600China

Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway *** stability control of automatically formed roadway is the key to the successful application of the new *** order to realize the stability control of the roadway surrounding rock,the mechanical model of the roof and rib support structure is established,and the influence mechanism of the automatically formed roadway parameters on the compound force is *** this basis,the roof and rib support structure technology of confined lightweight concrete is proposed,and its mechanical tests under different eccentricity are carried *** results show that the bearing capacity of confined lightweight concrete specimens is basically the same as that of ordinary confined concrete *** bearing capacity of confined lightweight concrete specimens under different eccentricities is 1.95 times higher than those of U-shaped steel *** comparing the test results with the theoretical calculated results of the confined concrete,the calculation method of the bearing capacity for the confined lightweight concrete structure is *** design method of confined lightweight concrete support structure is established,and is successfully applied in the extra-large mine,Ningtiaota Coal Mine,China.

关键词： automatically roadway with non-pillar confined lightweight concrete roof and rib support mechanical model bearing behaviour

Conductive catalysis by subsurface transition metals

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National Science Review 2024年第1期11卷 86-93页

作者： xin deng Caiyan Zheng Yangsheng Li Zeyu Zhou Jiamin Wang Yihua Ran Zhenpeng Hu Fan Yang Landong Li Frontiers Science Center for New Organic Matter College of ChemistryNankai University School of Physics Nankai University School of Physical Science and Technology Shanghai Tech University School of Materials Science and Engineering Nankai University Haihe Laboratory of Sustainable Chemical Transformations

The nature of catalysis has been hotly pursued for over a century, and current research is focused on understanding active centers and their electronic structures. Herein, the concept of conductive catalysis is proposed and verified by theoretical simulations and experimental observations. Metallic systems containing buried catalytically active transitional metals and exposed catalytically inert main group metals are constructed, and the electronic interaction between them via metallic bonding is disclosed. Through the electronic interaction, the catalytic properties of subsurface transitional metals(Pd or Rh) can be transferred to outermost main group metals(Al or Mg) for several important transformations like semi-hydrogenation,Suzuki-coupling and hydroformylation. The catalytic force is conductive, in analogy with the magnetic force and electrostatic force. The traditional definition of active centers is challenged by the concept of conductive catalysis and the electronic nature of catalysis is more easily understood. It might provide new opportunities for shielding traditional active centers against poisoning or leaching and allow for precise regulation of their catalytic properties by the conductive layer.

关键词： electronic interaction conductive catalysis subsurface transition metal