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Chinese Journal of Chemistry 2011年第1期29卷 131-134页

作者： Qi, Gang liu, Wei bei, Zhining Department of Chemistry and Biology Yaneheng Institute of Technology Yancheng Jiangsu 224003 China School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210093 China

An efficient route for the synthesis of 5-substituted 1H-tetrazole via [2＋3] cycloaddition of nitriles and sodium azide is reported using Fe3O4/ZnS hollow nanospheres as a magnetic separable heterogeneous catalyst. The catalyst is very efficient, affording excellent yields and can be reused for several circles. In addition, the Fe3O4 inner shell exhibits magnetism, making the catalyst easily separated by a magnet.

关键词： Fe3O4/ZnS hollow nanospheres 1H-tetrazoles catalyst

Temperature influences of the recoil characteristics for aluminum honeycomb buffer in the tether-net launcher

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Defence Technology（防务技术） 2023年第11期29卷 39-54页

作者： Wen-hui Shi Shuai Yue Chun-bo Wu Zhou liu Zhi liu bei-bei Zhao Zhong-hua Du Guang-fa Gao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Aerospace System Engineering Shanghai Shanghai201109China Xi'an North Qinghua Electromechancal Co. LTDXi'an710038China

Fluctuations in outer space's temperature would affect the spacecraft's regular *** paper aims to study the temperature influences of the aluminum honeycomb buffer in the tether-net ***,a buffer structure was designed to attenuate the pyroshock generated by the pyrotechnic ***,the mechanical properties of aluminum honeycomb at different temperatures were obtained through quasi-static compression ***,the internal ballistic responses of the launcher were gained by the closed bomb tests and the equivalent classical interior ballistic ***,the recoil performance of the launcher with aluminum honeycomb buffer at different temperatures was *** is revealed that the aluminum honeycomb crushing force gradually decreases with the temperature *** peak pressure,burning rate coefficient and velocity increase while the peak time decreases with the temperature increase for the interior *** the launcher recoil responses,the average launch recoil decreases if the aluminum honeycomb doesn't enter the dense *** impact acceleration,projectile velocity and displacement increase as the temperature *** paper spotlights the temperature's influence on the recoil characteristics of the aluminum honeycomb buffer,which provides a new idea for buffering technology of pyrotechnic devices in a complex space environment.

关键词： Tether-net launcher Temperature Aluminum honeycomb buffer Interior ballistic responses Launch recoil characteristics

An efficient stiffness analysis model based on shear deformation theory for flexible skin shear variable-sweep wing

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Chinese Journal of Aeronautics 2024年第10期37卷 445-458页

作者： Yue BAI Guang YANG Hong XIAO Hongwei GUO Rongqiang liu bei liu State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China China Aerodynamics Research and Development Center Institute of High-Speed AerodynamicsMianyang 621000China

Fixed-wing aircraft cannot maintain optimal aerodynamic performance at different flight speeds. As a type of morphing aircraft, the shear variable-sweep wing(SVSW) can dramatically improve its aerodynamic performance by altering its shape to adapt to various flight *** order to achieve smooth continuous shear deformation, SVSW's skin adopts a flexible composite skin design instead of traditional aluminum alloy materials. However, this also brings about the non-linear difficulty in stiffness modeling and calculation. In this research, a new SVSW design and efficient stiffness modeling method are proposed. Based on shear deformation theory, the flexible composite skin is equivalently modeled as diagonally arranged nonlinear springs, simulating the elastic force interaction between the skin and the mechanism. By shear loading tests of flexible composite skin, the accuracy of this flexible composite skin modeling method is verified. The SVSW stiffness model was established, and its accuracy was verified through static loading tests. The effects of root connection, sweep angles, and flexible composite skin on the SVSW stiffness are analyzed. Finally, considering three typical flight conditions of SVSW: low-speed flow(Ma = 0.3,Re = 5.82 × 10^(6)), transonic flow(Ma = 0.9, Re = 3.44 × 10^(6)), and supersonic flow(Ma = 3,Re = 7.51 × 10^(6)), the stiffness characteristics of SVSW under flight conditions were *** calculated results guide the application of SVSW.

关键词： Shear variable-sweep wing(SVSW) Flexible composite skin Morphing mechanism Stiffness analysis Loading tests Structure

Structural Properties of Homomorphism Dilation Systems

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Chinese Annals of Mathematics,Series B 2020年第4期41卷 585-600页

作者： Deguang HAN David R.LARSON bei liu Rui liu Department of Mathematics University of Central FloridaOrlando 32816USA. Department of Mathematics Texas A&M UniversityCollege Station 77843USA. School of Science Tianjin University of TechnologyTianjin 300384China. Corresponding author.School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071China.

Inspired by some recent development on the theory about projection valued dilations for operator valued measures or more generally bounded homomorphism dilations for bounded linear maps on Banach algebras,the authors explore a pure algebraic version of the dilation theory for linear systems acting on unital algebras and vector *** introducing two natural dilation structures,namely the canonical and the universal dilation systems,they prove that every linearly minimal dilation is equivalent to a reduced homomorphism dilation of the universal dilation,and all the linearly minimal homomorphism dilations can be classified by the associated reduced subspaces contained in the kernel of synthesis operator for the universal dilation.

关键词： Linear systems Linearly minimal homomorphism dilation systems Principle and universal dilations Equivalent dilation systems

残余胆固醇与进展为主要不良心血管事件的非罪犯病变易损斑块的相关性研究

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中国全科医学 2025年第3期28卷 299-304页

作者：杨红刘成刘森邵琪琪夭元昊付真彦新疆医科大学第一附属医院心脏中心新疆维吾尔自治区乌鲁木齐市830054

背景残余胆固醇(RC)被认为是动脉粥样硬化性心血管疾病的重要危险因素,而冠状动脉非罪犯病变(NCCLs)进展也是影响冠心病患者预后的重要因素,但是残余胆固醇与进展为主要不良心血管事件(MACE)的NCCLs易损斑块的关系尚不明确。目的探讨R... 详细信息

背景残余胆固醇(RC)被认为是动脉粥样硬化性心血管疾病的重要危险因素,而冠状动脉非罪犯病变(NCCLs)进展也是影响冠心病患者预后的重要因素,但是残余胆固醇与进展为主要不良心血管事件(MACE)的NCCLs易损斑块的关系尚不明确。目的探讨RC对发生MACE的NCCLs易损斑块的预测价值及长期预后的相关性。方法选取2015年2月—2022年2月于新疆医科大学第一附属医院心脏中心住院的488例冠心病患者为研究对象,通过电子病历系统收集患者基线资料,行冠状动脉造影及光学相干断层扫描OCT。入组患者在出院1、3、6和12个月接受预定随访。采用Spearman秩相关检验探究RC与NCCLs中薄纤维帽粥样硬化斑块(TCFA)斑块特征的相关性。采用多因素Logistic回归分析探究NCCLs中TCFA发生MACE的影响因素。绘制受试者工作特征曲线(ROC曲线)并计算ROC曲线下面积(AUC),探究RC对NCCLs中TCFA发生MACE的预测价值。结果共纳入488例冠心病患者,根据NCCLs是否发生MACE将患者分为发生MACE组(n=38)和未发生MACE组(n=450)。通过OCT识别NCCLs的斑块特征,共分析了749个NCCLs斑块,304个NCCLs斑块最小管腔面积(MLA)<3.5 mm^(2)。随访期间38例(7.8%)患者共发生了41例次NCCLs斑块引起的MACE事件,18例(3.7%)患者发生了支架内再狭窄,15例(3.1%)发生了不确定因素的死亡。发生MACE组患者高血压、糖尿病、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、RC、糖化血红蛋白(Hb A1c)、TCFA、MLA<3.5 mm^(2)比例高于未发生MACE组(P<0.05)。105例患者检查出TCFA,其中22例发生MACE(发生MACE的TCFA组),83例未发生MACE(未发生MACE的TCFA组)。发生MACE的TCFA组糖尿病比例与RC高于未发生MACE的TCFA组(P<0.05)。Spearman秩相关分析结果示,RC与最薄纤维帽厚度、MLA呈负相关(r_(s)=-0.665、-0.771,P<0.05),与最大脂质弧度、巨噬细胞浸润呈正相关(r_(s)=0.806、0.481,P<0.05)。多因素Logistic回归分析结果显示糖尿病(OR=3.410,95%CI=1.165~9.988,P=0.025)、高RC水平(OR=5.879,95%CI=1.436~24.073,P=0.014)是NCCLs中TCFA发生MACE的危险因素。绘制RC预测NCCLs中TCFA发生MACE的ROC曲线,结果显示AUC为0.695(95%CI=0.571~0.819,P=0.005),最佳截断值为0.606 mmol/L,灵敏度、特异度分别为0.818、0.518。结论 RC水平升高可能是冠心病患者中NCCLs易损斑块发生MACE的危险因素,对NCCLs中TCFA发生MACE有一定的预测价值。

关键词：冠心病冠状动脉粥样硬化血脂异常主要不良心血管事件冠状动脉非罪犯病变残余胆固醇相关性研究

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Black goji berry (Lycium ruthenicum) tea has higher phytochemical contents and in vitro antioxidant properties than red goji berry (Lycium barbarum) tea

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Food Quality and Safety 2020年第4期4卷 193-201页

作者： bei liu Qingqing Xu Yujing Sun College of Food Science and Technology Zhejiang University of TechnologyHangzhouChina

Goji berry tea, a traditional herbal tea, is the main ate mode of goji berry in Asia, yet few studies in comparison with red goji berry tea and black goji berry tea are carried out. This study investigated the effects of water temperature and soak time on the colour, phytochemicals, and the antioxidant capacity [2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), and the ferric-reducing antioxidant power (FRAP)] of two goji berry tea. A comparison of the bioactive compounds and antioxidant activities between black and red goji berry tea was conducted. Results showed that both red and black goji berry tea were rich in phytochemicals, giving high antioxidant ability. The levels of bioactive compounds and the antioxidant activity of the two goji berry tea increased as the increases in soak temperature and time. Black goji berry tea had higher phytochemicals and antioxidant property than those of red goji berry tea. Infused at 100° water for the same time, the levels of total polysaccharides (150 mg/100 ml), total polyphenols (238 mg/ml), and antioxidant capacity (550 μmol/100 ml) of black goji berry tea were 3.5, 2, and 5 times higher, respectively, in comparison with red goji berry tea. The results of this study demonstrate that hot drink of goji berry in China is a good habit and black goji berry tea may be a better choice.

关键词： red goji berry(L.barbarum) black goji berry(L.ruthenicum) goji tea phytochemicals antioxidant activity

Burden of mental disorders and risk factors in the Western Pacific region from 1990 to 2021

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World Journal of Psychiatry 2025年第1期15卷 93-105页

作者： Ya-Xin Xu Xiao-Xuan Niu Wen-Chang Jia Jing Wen Xue-Lin Cheng Yan Han Ming-Hui Peng Jing Zhou yao liu Sun-Fang Jiang Xiao-Pan Li Department of Health Management Centre Zhongshan HospitalFudan UniversityShanghai 200030China Department of General Practice Zhongshan HospitalFudan UniversityShanghai 200030China Department of Nutrition Zhongshan HospitalFudan UniversityShanghai 200032China School of Public Health Fudan UniversityShanghai 200032China

BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and *** To analyze the burden of MD in the WPR from 1990 to 2021,along with associated risk factors,to reveal changing trends and emerging *** We used data from the Global Burden of Disease 2021,analyzing prevalence,incidence,and disability-adjusted life years(DALYs)of MD from 1990 to *** methods included age-standardisation and uncertainty analysis to address variations in population structure and data *** Between 1990 and 2021,the prevalence of MD rose from 174.40 million cases[95%uncertainty interval(UI):160.17-189.84]to 234.90 million cases(95%UI:219.04-252.50),with corresponding DALYs increasing from 22.8 million(95%UI:17.22-28.79)to 32.07 million(95%UI:24.50-40.68).During this period,the burden of MD shifted towards older age *** and anxiety disorders were predominant,with females showing higher DALYs for depressive and anxiety disorders,and males more affected by conduct disorders,attention-deficit hyperactivity disorder,and autism spectrum ***,New Zealand,and Malaysia reported the highest burdens,whereas Vietnam,China,and Brunei Darussalam reported the ***,childhood sexual abuse and bullying,and intimate partner violence emerged as significant risk *** This study highlights the significant burden of MD in the WPR,with variations by age,gender,and *** coronavirus disease 2019 pandemic has exacerbated the situation,emphasizing the need for a coordinated response.

关键词： Mental disorders Western pacific region Global Burden of Disease Risk factors Disability-adjusted life years

A smart DNA nanodevice for ATP-activatable bioimaging and photodynamic therapy

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Science China Chemistry 2020年第10期63卷 1490-1497页

作者： bei liu Rui Ma Jian Zhao Yuliang Zhao Lele Li School of Science Minzu University of ChinaBeijing 100081China CAS Key Laboratoty for Biomedical Effects of Nanomaterials and Nanosafety and CAS Center for Excellence in Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China GBA Research Innovation Institute for Nanotechnology Guangdong 510700China

Rational design of activatable photosensitizers for controlled generation of singlet oxygen remains a challenge for precise photodynamic therapy(PDT).Herein,we present an aptamer-based nanodevice for adenosine 5′-triphosphate(ATP)-activatable bioimaging and *** nanodevice is constructed by modifying ATP-responsive duplex DNA units and polyethylene glycol on the surface of a gold nanoparticle(AuNP)through the thiolate-Au *** DNA units were designed by the hybridization of the ATP aptamer strand with a methylene blue(MB)-modified complementary DNA(cDNA).The close proximity of MB to the surface of AuNP results in the low photodynamic activity of MB(OFF state).Once internalized into cancer cells,the ATP-binding induced conformation switch of aptamer strand leads to the release of the MB-bearing DNA strand from AuNPs,resulting in the activatable generation of singlet oxygen under light irradiation(ON state).We demonstrate that the DNA nanodevice represents a promising platform for ATP-responsive bioimaging and specific PDT in vitro and in *** work highlights a potential way for specific tumor diagnosis and therapy.

关键词： DNA nanotechnology ATP-activatable photodynamic therapy bioimaging

Existence,Multiplicity and Infinite Solvability of Positive Solutions for One-Dimensional p-Laplacian

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Acta Mathematica Sinica,English Series 2005年第4期21卷 691-698页

作者： Qing liu yao Department of Applied Mathematics Nanjing University of Finance and Economics Nanjing 210003 P. R. China

The existence, multiplicity and infinite solvability of positive solutions are established for some two-point boundary value problems of one-dimensional p-Laplacian. In this paper, by multiplicity we mean the existenc... 详细信息

关键词： One-dimensional p-Laplacian Positive solution Existence Multiplicity Infinite solvability

Interior-stress fields produced by a general axisymmetric punch

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Friction 2022年第4期10卷 530-544页

作者： Longxiang YANG Zhanjiang WANG Weiji liu Guocheng ZHANG bei PENG School of Automotive Engineering Geely University of ChinaChengdu 641423China Department of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Center for Robotics University of Electronic Science and Technology of ChinaChengdu 611731China

This work is a supplement to the work of Sneddon on axisymmetric Boussinesq problem in 1965 in which the distributions of interior-stress fields are derived here for a punch with general profile.A novel set of mathematical procedures is introduced to process the basic elastic solutions(obtained by the method of Hankel transform,which was pioneered by Sneddon)and the solution of the dual integral *** processes then enable us to not only derive the general relationship of indentation depth D and total load P that acts on the punch but also explicitly obtain the general analytical expressions of the stress fields beneath the surface of an isotropic elastic *** usually known cases of punch profiles are reconsidered according to the general formulas derived in this study,and the deduced results are verified by comparing them with the classical ***,these general formulas are also applied to evaluate the von Mises stresses for several new punch profiles.

关键词： axisymmetric Boussinesq problem interior stress Hankel transform dual integral equations