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Possible Habitats for nH_(3),nH_(2)D,H^(13)Cn,HC^(15)n,SO,and C^(18)O in the Initial Conditions of High-mass Star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

作者： Quan-Ling Cui Chuan-Peng Zhang Jun-Jie wang national Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted fro... 详细信息

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)nditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the n-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for nH_(3),nH_(2)D,H^(13)Cn,HC^(15)n,SO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97n,G23.98,G23.44,G23.97S,G25.38,and *** found that the nH3cores are in good agreement with the 3.5 mm peak emission,but the nH_(3)is much more extended than the 3.5 mm emission *** SO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any SO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the nH_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the nH_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational

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OSDA-free synthesis of FeZSM-22 zeolite from natural minerals for n-octane hydroisomerization

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Chinese Journal of Chemical Engineering 2024年第2期66卷 51-59页

作者： Tiesen Li Ting Chen Yinghui Ye Peng Dong Tinghaiwang Qingyan Cui Chan wang Yuanyuan Yue national Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350002China Qingyuan Innovation Laboratory Quanzhou 362801China

A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron *** Fe ZSM-22zeolite with optimal crystallinity and purity can be obtained by systematically adjusting feed composition and synthesis *** show that Fe ZSM-22 zeolite synthesized with OSDA-free owns high crystallinity,obvious thin needle-shaped morphology and high Bronsted/Lewis acid ***,when used for n-octane hydroisomerization reaction,its derived catalyst exhibits the best catalytic performance reflected by the highest selectivity to C_(8)isomers compared to the two reference catalysts prepared based on a Fe-containing and a Fe-free ZSM-22 synthesized through an OSDA-directed route from natural diatomite and conventional chemicals,*** work provides an alternative route to sustainably synthesizing heteroatomic zeolites with high performance.

关键词： FeZSM-22 zeolite OSDA-free synthesis natural minerals n-octane hydroisomerization

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Enhanced thermoelectric performance enabled by compositing ZrO_(2)in n-type SiGe alloy with low thermal conductivity

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Rare Metals 2024年第3期43卷 1167-1176页

作者： Meng-Fei wang Hua-Jun Lai Ji-Sheng Liang Jun-Liang Chen wang-Yang Ding Qi Zhou Ying Peng Cheng-Yan Liu Lei Miao Guangxi Key Laboratory for Relativity Astrophysics State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite StructuresSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China Guangxi Academy of Sciences Nanning530007China Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesGuilin University of Electronic TechnologyMinistry of EducationGuilin541004China Guangxi Key Laboratory of Precision navigation Technology and Application School of Information and CommunicationGuilin University of Electronic TechnologyGuilin541004China

SiGe-based thermoelectric(TE)materials have gained increasing interests due to their low maintenance costs,environmental friendliness and long ***,the intrinsically high thermal conductivity of Si-based materials also results in poor TE *** this investigation,a zirconia(ZrO_(2))composite strategy was applied to an n-type SiGe alloy,tremendously elevating its TE *** mechanical alloying and spark plasma sintering(SPS)processes,the ZrO_(2)induced the formation of nanopores in the SiGe matrix via phosphorus ***,such increase in porosity enhanced the phonon scattering and dramatically suppressed lattice thermal conductivity,from 2.83 to 1.59 W·m^(-1)·K^(-1)at 873 ***,reduced phosphorus doping led to an increase in Seebeck coefficients and a relatively minor decrease in electrical conductivity,The power factor didn't deteriorate significantly,either,as its maximum of~3.43 mW·m^(-1-)K^(-2)was achieved at 873 K with(Si_(0.8)Ge_(0.2))_(0.097)P_(0.03)(ZrO_(2))_(0.003).In short,a peak figure of merit(ZT)of~1.27 at 873 K and an average ZT~0.7 from 323 to 873 K were *** study demonstrates that the electrical and thermal transportation of SiGe material can be synergistically tuned by compositing ZrO_(2),illustrating a novel strategy to optimize the TE properties of bulk materials.

关键词： Thermoelectric SiGe alloy ZrO2 composting P element adsorption nanopores

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The reformation of catalyst:From a trial-and-error synthesis to rational design

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nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),n_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao Zheng Zi-An Zhou Tiao Feng Hui Li Cheng-Hua Sun nüwang Yang Tian Yong Zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

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numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length n as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of n.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

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Enhanced potency of an IgM-like nanobody targeting conserved epitope in SARS-CoV-2 spike n-terminal domain

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2726-2737页

作者： Bo Liu Honghui Liu Pu Han Xiaoyun wang Chunmei wang Xinxin Yan Wenwen Lei Ke Xu Jianjie Zhou Jianxun Qi Ruiwen Fan Guizhen Wu Wen-xia Tian George F.Gao Qihui wang College of Veterinary Medicine Shanxi Agricultural University030801 JinzhongChina CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CAS)100101 BeijingChina School of Life Sciences Yunnan University650504 KunmingYunnan ProvinceChina nHC Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention(China CDC)102206 BeijingChina Savaid Medical School University of Chinese Academy of Sciences101408 BeijingChina

Almost all the neutralizing antibodies targeting the receptor-binding domain(RBD)of spike(S)protein show weakened or lost efficacy against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)emerged or emerging variants,such as Omicron and its *** suggests that highly conserved epitopes are crucial for the development of neutralizing ***,we present one nanobody,n235,displaying broad neutralization against the SARS-CoV-2 prototype and multiple variants,including the newly emerged Omicron and its ***-electron microscopy demonstrates n235 binds a novel,conserved,cryptic epitope in the n-terminal domain(nTD)of the S protein,which interferes with the RBD in the neighboring S *** neutralization mechanism interpreted via flow cytometry and Western blot shows that n235 appears to induce the S1 subunit shedding from the trimeric S ***,a nano-IgM construct(Mn235),engineered by fusing n235 with the human IgM Fc region,displays prevention via inducing S1 shedding and cross-linking virus *** to n235,Mn235 exhibits varied enhancement in neutralization against pseudotyped and authentic viruses in *** intranasal administration of Mn235 in low doses can effectively prevent the infection of Omicron sub-variant BA.1 and XBB in vivo,suggesting that it can be developed as a promising prophylactic antibody to cope with the ongoing and future infection.

关键词： doses prevention conserved

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Genetic and biological properties of H9n2 avian influenza viruses isolated in central China from2020 to 2022

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Journal of Integrative Agriculture 2024年第8期23卷 2778-2791页

作者： Libin Liang Yaning Bai Wenyan Huang Pengfei Ren Xing Li Dou wang Yuhan Yang Zhen Gao Jiao Tang Xingchen Wu Shimin Gao Yanna Guo Mingming Hu Zhiwei wang Zhongbing wang Haili Ma Junping Li College of Veterinary Medicine Shanxi Agricultural UniversityJinzhong 030801China Shanxi Provincial Animal Disease Prevention and Control Center Taiyuan 030000China

The H9n2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in *** H9n2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public ***,there is a lack of in-depth research on the prevalence of H9n2 viruses in Shanxi Province,central *** this study,we isolated 14 H9n2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different *** study on animals revealed that the H9n2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these *** viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and *** the cellular level,the replication ability of different H9n2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9n2 viruses at the cellular *** antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic *** research provides crucial data to help understand the prevalence and biological characteristics of H9n2 AIVs in central *** also highlights the necessity of enhancing the surveillance of H9n2 AIVs.

关键词： avian influenza virus H9n2 central China pathogenicity antigenicity

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Effect of(Cr,V)_(2)(C,n)on the Microstructure and Mechanical Properties of WC-10Co Cemented Carbides

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1138-1148页

作者： LI Xiangkun wang Lu YE Jinwen School of Materials Science and Engineering Sichuan UniversityChengdu 610065China

WC-10Co cemented carbides with finer WC and narrower grain size distributions are produced by using(Cr,V)_(2)(C,n)as grain growth *** a result,with the increase of(Cr_(0.9),V_(0.1))_(2)(C,n)and(V_(0.9),Cr_(0.1))_(2)(C,n),the grains size of WC and mean free path of Co phase decrease,and adjacency of WC *** and homogenization of grains enhance the transverse rupture strength(TRS)and the ***,the deflection and bridging of cracks keep the fracture toughness at a respectable *** WC-10Co-0.6(Cr_(0.9),V_(0.1))_(2)(C,n)-0.025(V_(0.9),Cr_(0.1))_(2)(C,n)cemented carbides exhibit excellent comprehensive mechanical properties with the TRS of 4602.6 MPa,hardness of 1835 kg/mm^(2),and fracture toughness of 10.39 MPa·m^(1/2),***,the large pores are caused by excess n larger than 0.03 wt%and deteriorates the mechanical *** provide a new approach to WC-Co cemented carbides preparation with a narrow grain size distribution by adding novel grain growth inhibitors.

关键词： (Cr,V)_(2)(C,n) nutrient content WC grains size microstructure mechanical properties

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Connecting cellular mechanisms and extracellular vesicle cargo in traumatic brain injury

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neural Regeneration Research 2024年第10期19卷 2119-2131页

作者： nikita Ollen-Bittle Austyn D.Roseborough Wenxuan wang Jeng-liang D.Wu Shawn n.Whitehead Department of Anatomy and Cell Biology Western UniversityLondonONCanada Schulich School of Medicine and Dentistry Western UniversityLondonONCanada Deparment of Clinical neurological Sciences Western UniversityLondonONCanada

Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.

关键词： axonal injury biomarkers blood-brain barrier chronic traumatic encephalopathy extracellular vesicles glial activation neuroinflammation traumatic brain injury

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