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The absorbing properties of Fe_(73.5) Cu_1 Nb_3Si_(13.5)B_9 amorphous powder/S-glass fiber-reinforced epoxy composite panels

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Rare Metals 2013年第3期32卷 294-298页

作者： Xia-Lian zheng zheng-hou zhu Xiao-Min Li School of Materials Science and Engineering Nanchang University Physics Science and Engineering Technology Institute Yichun College

Fe73.5Cu1Nb3Si13.5B9 （or FeCuNbSiB） powder/ S-glass fiber-reinforced epoxy composite panels were pre- pared by mold pressing method. Metallographic analysis shows that the amorphous powders are evenly distributed between the layers of S-glass fibers. The effects of the Fe- CuNbSiB powder mass fraction on the complex permittivity, complex permeability, and microwave absorption of the composite panels have been studied in the frequency range of 2.6-18.0 GHz. The complex permittivity of the composite panels with different mass fractions of the FeCuNbSiB powders shows several peaks in the 2.6-18.0 GHz fre- quency range. The complex permeability of the composites decreases with the increasing frequency in the frequency range of 8-18 GHz. The composite with FeCuNbSiB/epoxy mass ratio of 2.5：1.0 has excellent microwave absorption properties of a minimum reflection loss value -30.5 dB at 10.93 GHz for a thickness of 2 mm. A reflection loss exceeding -10 dB can be obtained in a broad frequency range of 3.2-18.0 GHz with a thickness of 1.15-5.00 mm. For the FeCuNbSiB composites, the magnetic loss is the dominant term for microwave absorption. The FeCuNbSiB powders are a possible candidate for high-performance microwave absorption filler.

关键词： Amorphous powders Composites Permeability Permittivity Absorbing properties

Force-sensitive properties of FeCuNbSiB powder/silicone rubber composite films

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Rare Metals 2016年第10期35卷 784-789页

作者： Jia Zhou zheng-hou zhu Xiao-Min Li Kang Du Bao-Ying Qiao Yuan Fu School of Materials and Engineering Nanchang University

Composite films of different contents were prepared by Fe73.5Cu1Nb3Si13.5B9 powder as compound phase and silicone rubber as matrix phase. The thickness of film is 200 μm. Values of impedance, Z, under pressure stress were measured by TH2816LCR digital bridge. LYYL-500N high-grade-type microcomputer control pressure testing machine was used to conduct program control loading with a speed of 0.1 mm·min^-1. The results show that composite films of different contents （25 vol%, 30 vol%, and 35 vol%） have excellent force-sensitive properties in both loading process and unloading process, especially when the stress is below 0.2 MPa, the stress- impedance （SI） and ＋｜k｜ values of composite films are much higher than that in the range of 0.2-1.0 MPa. The force- sensitive properties of loading process are superior to unloading process. While the frequency is 1 kHz, the force-sensitive properties of composite films are better than 50 kHz. The optimal temperature of powder heat treatment is 500 ℃. Composite film which was prepared by this kind of powder has a good force-sensitive property.

关键词： Composite films Stress-impedance effect Force-sensitive properties

Terminal attitude selection method of missile attack aircraft

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Chinese Journal of Aeronautics 2024年第2期37卷 385-400页

作者： Peng hou Yang PEI Yuxue GE Mengjie zhu School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Research Department Shanghai Electro-Mechanical Engineering InstituteShanghai 201108China

The appropriate terminal attitude of missile is important to improve the damage effectiveness of fragmentation warhead against aircraft targets.In this paper,three missile terminal attitude selection methods are proposed to solve the problem of terminal attitude selection in different situations according to their respective evaluation indexes.The MVE-based method uses the damage probability of each detonation point around the aircraft at a given attitude of missile to calculate the Mean Volume of Effectiveness(MVE)at the corresponding attitude,and then uses the MVE for different attitudes to select the terminal strike attitude.The detonation position-based method addresses the case where the missile detonation position can be assessed in advance.Given the effects of missile guidance errors and fuze activation position errors,Monte Carlo simulations are used to calculate the damage probability of aircraft with different strike attitudes,from which the terminal strike attitude is selected.The BP-ANN model-based method uses the constructed Back Propagation Artificial Neural Network(BP-ANN)model instead of simulation to calculate the evaluation indexes in the corresponding cases of MVE-based method and Detonation position-based method,which can improve the efficiency of attitude selection.Simulations are conducted for different scenarios to verify the feasibility and effectiveness of the proposed method.

关键词： Aircraft vulnerability Attitude selection BP-ANN Damage probability Damage effectiveness

Appreciable Enhancement of Photocatalytic Performance for N-doped SrMoO_(4) via the Vapor-thermal Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 24-31页

作者：恽志强戴振翔 zhu Liwei zheng Ganhong School and Materials Science and Engineering Anhui UniversityHefei 230601China School of Physics and Optoelectronics Engineering Anhui UniversityHefei 230601China

A series of nitrogen-doped SrMoO_(4) with different Sr/N mole ratio (R=0,0.05,0.10,0.15,0.20,0.40,and 0.60) were synthesized using urea as the N source via the vapor-thermal method.The photocatalytic degradation ability of all samples was evaluated using methylene blue (MB) as a target contaminant.The band gaps of N-doped samples are all higher than that of pristine ones,which is only 3.12 eV.BET specific surface area S_(BET) and pore volume are increased due to the N doping.And the greater increase of S_(BET),the faster the photodegradation speed of methylene blue on SrMoO_(4).More specifically,the degradation efficiency of MB is improved up to 87%in 100 min.

关键词： SrMoO_(4) photocatalytic property nitrogen element doping

Efficacy of scraping therapy on blood pressure and sleep quality in stage Ⅰ and Ⅱ essential hypertension: A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第1期22卷 12-21页

作者： zheng-gang zhu Jian-ru Wang Xiao-yan Pan School of Nursing Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Health Sciences Universiti Sains MalaysiaKubang Kerian 16150KelantanMalaysia Department of Cardiovascular Medicine the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

Background Scraping therapy is widely used in treating stage I and II essential hypertension in China.However,there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential hypertension.Search strategy Seven electronic databases(PubMed,Scopus,Cochrane Library,Web of Science,EBSCO,China National Knowledge Infrastructure and Wanfang Data electronic databases)were searched from inception to December 2022.Based on the principle of combining subject words with text words,the search strategy was constructed around search terms for“scraping therapy,”“scraping,”“Guasha,”“Gua sha,”“hypertension,”and“high blood pressure”during the database searches.Inclusion criteria Randomized controlled trials(RCTs)were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy intervention.The intervention group received antihypertensive drugs and scraping therapy,while the control group only took antihypertensive drugs.Data extraction and analysis Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the meta-analysis.The quality of the selected RCTs was assessed using the PEDro scale.The sensitivity analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify any studies with greater influence on the outcome.Subgroup analysis was performed to find the source of heterogeneity.Funnel plots were used to evaluate the publication bias of included studies.Results Nine RCTs including 765 participants were selected.Meta-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure(mean difference[MD]=?5.09,95%confidence interval[CI]=?6.50 to?3.67,P<0.001)and diastolic blood pressure(MD=?2.66,95%CI=?3.17 to?2.14,P<0.001).Subgroup analysis showed that scraping therapy improved sleep quality in mid

关键词： Scraping therapy Essential hypertension Efficacy Blood pressure Sleep quality Systematic review Meta-analysis

Exosomal microRNAs in hepatocellular carcinoma,expanding research field

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World Journal of Gastroenterology 2024年第20期30卷 2618-2620页

作者： Bo-Hao zheng Xiao-Jian Ni hou-Bao Liu Department of Biliary Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Biliary Tract Disease Center of Zhongshan Hospital Fudan UniversityShanghai 200032China Biliary Tract Disease Institute Fudan UniversityShanghai 200032China Cancer Center Zhongshan HospitalFudan UniversityShanghai 200032China Shanghai Biliary Tract Minimal Invasive Surgery and Materials Engineering Research Center Shanghai 200032China

In this editorial we comment on the review by Wang et al published in the recent issue of the World Journal of Gastroenterology in 2023.Small extracellular vesicles(exosomes)play important roles in the tumor microenvironment.In this review,the authors introduce the following points:(1)The composition and function of exosomal microRNAs(miRNAs)of different cell origins in hepatocellular carcinoma(HCC);(2)the crosstalk between exosomal miRNAs from stromal cells and immune cells in the tumor microenvironment and the progression of HCC;and(3)the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC.In addition,the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC was introduced.In this review,the authors give us an overview of the exosomal RNA and summarize the function of exosomal RNA in HCC,which provides a deeper understanding of exosomal miRNAs to the readers.

关键词： Exosomes MicroRNA Hepatocellular carcinoma Liver cancer Tumor microenvironment

Stereochemical editing:Catalytic racemization of secondary alcohols and amines

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Chinese Chemical Letters 2024年第5期35卷 17-31页

作者： Jun Zhang Zhiyao zheng Can zhu Department of Chemistry Fudan UniversityShanghai 200438China Department of Organic Chemistry Arrhenius LaboratoryStockholm UniversityStockholm 10691Sweden

Chiral alcohols and amines are important structural units widely existing in pharmaceuticals,agrochemicals,and food additives.Dynamic kinetic resolution(DKR)is an efficient strategy to deliver optically active alcohols and amines from their racemates.For the development of DKR method,racemization catalyst plays as a crucial element with the requirement of compatibility with the kinetic resolution(KR)system.In this paper,recent advance in the catalytic racemization of secondary alcohols and amines is summarized based on different types of racemizing intermediates,which are redox racemization via ketone/imine intermediates,racemization via radical intermediates,and racemization via carbocation intermediates.Enzymatic racemization of secondary alcohols and amines is also enclosed.

关键词： Racemization Secondary alcohols Amines Kinetic resolution Dynamic kinetic resolution

Robust Distributed Model Predictive Control for Formation Tracking of Nonholonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 560-562页

作者： Zhigang Luo Bing zhu Jianying zheng Zewei zheng School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Dear Editor,This letter proposes a robust distributed model predictive control(MPC) strategy for formation tracking of a group of wheeled vehicles subject to constraints and disturbances. Formation control has attract... 详细信息

关键词： letter constraints searching

Systematic pan-cancer analysis reveals OGT and OGA as potential biomarkers for tumor microenvironment and therapeutic responses

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Genes & Diseases 2024年第4期11卷 1-4页

作者： Chunyan hou Ci Wu Wenge zhu Huadong Pei Junfeng Ma Department of Oncology Lombardi Comprehensive Cancer CenterGeorgetown UniversityWashingtonDC 20007USA Department of Biochemistry and Molecular Medicine School of Medicine and Health ScienceGeorge Washington UniversityWashingtonDC20052USA

Protein O-linkedβ-N-acetylglucosamine(O-GlcNAc)modification(O-GlcNAcylation)is a unique monosaccharide modification of essential importance in physiology and pathology.1,2 As a highly dynamic process,O-GlcNAcylation is mediated by two paired enzymes:O-GlcNAc transferase(OGT)and O-GlcNAcase(OGA),which add or remove the modification from proteins,respectively.Emerging evidence demonstrates that the aberrant O-GlcNAcylation underlies the initiation,progression,and metastasis of cancer.

关键词： metastasis pathology therapeutic