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Dynamics and Thermodynamics of Porous HMX-like Material Under Shock

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Communications in Theoretical Physics 2009年第11期52卷 901-908页

作者： XU Ai-Guo zhang guang-Cai zhang ping PAN Xiao-Fei ZHU Jian-Shi National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009-26 Beijing 100088 China

Strong shock may induce complex processes in porous materials. We use the newly developed materialpoint-method to simulate such processes in an HMX-like material. To pick out relevant information, morphological characterization is used to treat with the temperature map. Via the Minkowski funetional analysis the dynamics and thermodynamics of the shock wave reaction on porous HMX-like material are studied. The geometrical and topological properties of the ＂hot-spots＂ are revealed. Numerical results indicate that, shocks in porous materials are not simple jump states as classically viewed, but rather are a complex sequence of compressions and rarefactions. They cover a broad spectrum of states. We can use coarse-grained description to the wave series. A threshold value of temperature presents a Turing pattern dynamical procedure. A higher porosity is generally preferred when the energetic material needs a higher temperature for initiation. The technique of data analysis can be used to other physical quantities, for example, density, particle velocity, some specific stress, etc. From a series of studies along the line, one may get a large quantity of information for desiring the fabrication of material and choosing shock strength according to what needed is scattered or connected ＂hot-spots＂. PACS numbers： ***, 05 Key words： porous material 70.-a, 05.40.-a, *** shock wave, Minkowski functionals

关键词： porous material shock wave Minkowski functionals

基于凝血级联途径研究血栓通注射液对博来霉素诱导肺纤维化大鼠的作用机制

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中国中药杂志 2024年第16期49卷 4313-4320页

作者：高云航宋玲陈腾飞郑志远杨依霏严灿梅张广平李晗中国中医科学院中药研究所北京100700 广西梧州制药(集团)股份有限公司广西梧州543000 广西三七综合利用技术重点实验室广西梧州543000

基于凝血级联途径探讨血栓通注射液(Xueshuantong Injection,XST)对博来霉素(bleomycin,BLM)所致肺纤维化大鼠的作用机制。将60只SD大鼠随机分为假手术组、模型组、吡非尼酮组(pirfenidone,PFD,50 mg·kg^(-1))组和27、54、81 mg·kg^(-1)XST组,采用气管内注入博来霉素(5 mg·kg^(-1))建立肺纤维化大鼠模型。24 h后,给药组分别给予相应的药物,假手术组、模型组给予等体积的生理盐水。第28天取材,观察大鼠肺部影像学与胶原纤维变化,并采用免疫荧光法检测大鼠肺组织α-平滑肌肌动蛋白(alpha-smooth muscle actin,α-SMA)、Ⅰ型胶原(collagenⅠ,Col-Ⅰ)、波形蛋白(vimentin,Vim)与E-钙黏蛋白(E-cadherin,E-cad)的表达,Western blot法检测肺组织α-SMA、Col-Ⅰ、Vim和E-cad的蛋白表达水平,采用酶联免疫吸附测定(enzyme-linked immunosorbent assay,ELISA)检测大鼠肺组织中凝血酶原片段(prothrombin fragment 1+2,F1+2)、凝血酶-抗凝血酶复合物(thrombin-antithrombin complex,TAT)、可溶性纤维蛋白单体复合物(soluble fibrin monomer complex,SFMC)和大鼠血纤蛋白原降解产物(fibrinogen degradation product,FDP)含量,最后通过实时荧光定量PCR(RT-qPCR)、Western blot与免疫荧光法测定肺组织中蛋白酶激活受体-1(protease-activated receptors-1,PAR-1)mRNA水平与蛋白水平。与模型组相比,给予XST后肺部扫描也显示出斑片状、不均匀的阴影,但这些阴影的密度低于模型组;同时大鼠肺部Ⅰ型胶原纤维显著减少;并且XST抑制上皮-间充质转化并下调α-SMA、Col-Ⅰ蛋白表达。在凝血系统方面,给予81 mg·kg^(-1)XST可显著降低SFMC与FDP的含量;同时81 mg·kg^(-1)XST可显著下调PAR-1 mRNA水平与蛋白水平。XST具有抗大鼠肺纤维化的作用,其机制可能与下调PAR-1从而改善凝血途径的异常有关。

关键词：肺纤维化血栓通注射液凝血级联博来霉素蛋白酶激活受体-1

Diabetic retinopathy identification based on multi-sourcefree domain adaptation

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1193-1204页

作者： guang-Hua zhang guang-ping Zhuo Zhao-Xia zhang Bin Sun Wei-Hua Yang Shao-Chong zhang School of Big Data Intelligent Diagnosis&Treatment Industry Taiyuan UniversityTaiyuan 030032Shanxi ProvinceChina Shanxi Key Laboratory of Intelligent Optimization Computing and Blockchain Technology Taiyuan Normal UniversityTaiyuan 030619Shanxi ProvinceChina Shanxi Eye Hospital Taiyuan 030002Shanxi ProvinceChina College of Computer Science and Technology Taiyuan Normal UniversityTaiyuan 030619Shanxi ProvinceChina Shenzhen Eye Institute Shenzhen Eye HospitalJinan UniversityShenzhen 518040Guangdong ProvinceChina

AIM:To address the challenges of data labeling difficulties,data privacy,and necessary large amount of labeled data for deep learning methods in diabetic retinopathy(DR)identification,the aim of this study is to develop a source-free domain adaptation(SFDA)method for efficient and effective DR identification from unlabeled ***:A multi-SFDA method was proposed for DR *** method integrates multiple source models,which are trained from the same source domain,to generate synthetic pseudo labels for the unlabeled target ***,a softmax-consistence minimization term is utilized to minimize the intra-class distances between the source and target domains and maximize the inter-class *** is performed using three color fundus photograph datasets(APTOS2019,DDR,and EyePACS).RESULTS:The proposed model was evaluated and provided promising results with respectively 0.8917 and 0.9795 F1-scores on referable and normal/abnormal DR identification *** demonstrated effective DR identification through minimizing intra-class distances and maximizing inter-class distances between source and target ***:The multi-SFDA method provides an effective approach to overcome the challenges in DR *** method not only addresses difficulties in data labeling and privacy issues,but also reduces the need for large amounts of labeled data required by deep learning methods,making it a practical tool for early detection and preservation of vision in diabetic patients.

关键词： diabetic retinopathy multisource-free domain adaptation pseudo-label generation softmaxconsistence minimization

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： Yan Yan guang-hao Shang Li-ping zhang Shao-ying Li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

Reaction mechanism between Al_(2)O_(3)–MgO refractory materials and rare earth high-carbon heavy rail steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1153-1163页

作者： Yi Wang guang-jie Song ping Shen Jian-zhong He Da-xian zhang Jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production *** explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)O_(3)–MgO refractories and SiO2-coated Al_(2)O_(3)–MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)O_(3)–MgO refractory was found to be more *** results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction *** based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface *** the inclusions at a smaller size has a specific effect on alleviating the erosion of *** with the erosion mechanism of Al_(2)O_(3)–MgO refractories,the interface reaction mechanism between Al_(2)O_(3)–MgO refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)O_(3)-MgO refractory Adhesion Surface tension Interface interaction

Design and application of copper/lithium composite anodes for advanced lithium metal batteries

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Rare Metals 2024年第3期43卷 942-970页

作者： Bin zhang Ji-ping Ma Yang Zhao Tong Li Jin-Lin Yang Zhan-Ling zhang Shi-Zhong Wei guang-Min Zhou School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471003China Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Shenzhen Geim Graphene Center Tsinghua-Berkeley Shenzhen InstituteTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Lithium(Li)is a promising candidate for nextgeneration battery anode due to its high theoretical specific capacity and low reduction ***,safety issues derived from the uncontrolled growth of Li dendrite and huge volume change of Li hinder its practical application.C onstructing dendrite-free composite Li anodes can significantly alleviate the above ***(Cu)-based materials have bee n widely used as substrates of the composite electrodes due to their chemical stability,excellent conductivity,and good mechanical ***/lithium(Cu/Li)composite anodes significantly regulate the local current density and decrease Li nucleation overp otential,realizing the uniform and dendrite-free Li *** this review,Cu/Li composite methods including electrodeposition,melting infusion,and mechanical rolling are systematically summarized and ***,design strategies of Cu-based current collectors for high performance Cu/Li composite anodes are *** challenges and future development for Cu/Li composite anodes are presented and *** hope that this review can provide a comprehensive understanding of Cu/Li composite methods of the latest development of Li metal anode and stimulate more research in the future.

关键词： Lithium metal batteries Cu/Li composite anode Electrodeposition Thermal melting infusion Mechanical rolling

新型冠状病毒肺炎疫情常态化防控时期在校医学生心理状况及其影响因素

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预防医学论坛 2024年第1期30卷 37-41,60页

作者：刘金杭马琳权张广平梅庆步刘宏伟刘丹齐齐哈尔医学院基础医学院黑龙江161006

目的调查新型冠状病毒肺炎(简称新冠肺炎)疫情常态化防控时期在校医学生的心理健康状况,并分析学生心理健康状况的影响因素,为医学教育教学改革提供学情数据。方法2021年9月,采用随机抽样调查法,选取齐齐哈尔医学院2940名在校医学生为... 详细信息

目的调查新型冠状病毒肺炎(简称新冠肺炎)疫情常态化防控时期在校医学生的心理健康状况,并分析学生心理健康状况的影响因素,为医学教育教学改革提供学情数据。方法2021年9月,采用随机抽样调查法,选取齐齐哈尔医学院2940名在校医学生为调查对象,应用自制心理调查问卷及一般健康问卷12项(GHQ-12)进行心理测试,评价医学生的总体心理健康状况。采用χ^(2)检验及非条件二分类logistic回归方法分析在校医学生心理健康状况的影响因素。结果共回收有效问卷2621份,GHQ-12结果显示心理异常者208人,心理异常检出率为7.9%(208/2621)。单因素分析结果显示,不同性别(χ^(2)=12.982,P<0.01)、年级(χ^(2)=20.888,P<0.01)、核酸检测次数(χ^(2)=11.072,P<0.05)、每周户外运动时间(χ^(2)=8.518,P<0.05)、身边同学隔离人数(χ^(2)=18.653,P<0.01)、单独隔离经历(χ^(2)=4.239,P<0.05)、线上线下教学模式偏好(χ^(2)=8.618,P<0.01)、线上学习效率(χ^(2)=137.256,P<0.01)、线上线下交替授课的影响程度(χ^(2)=99.050,P<0.01)、对疫情关注程度(χ^(2)=44.376,P<0.01)的学生心理健康状况差异有统计学意义。经二分类logistic回归分析显示,在校医学生的线上线下交替学习适应程度越高,其心理健康程度越佳(OR=1.771,P<0.01);线上学习效率越高,面对突发疫情状况时心理健康状况越佳(OR=1.069,P<0.01)。结论新冠肺炎疫情常态化防控时期,大部分在校医学生的心理健康状况处于正常水平,少数学生出现不良心理状况,不良心理状况受性别、年级、疫情动态化防控、校园封闭化管理和学习方式转变等因素影响。在校医学生线上学习效率和对线上线下交替授课的适应能力与其心理健康程度呈正相关。

关键词：医学生新冠肺炎疫情常态化防控心理健康线上教学

Conduction-convection coupled heat transfer around a hollow cylinder under different buoyancy forces

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Chinese Journal of Aeronautics 2024年第4期37卷 216-228页

作者： Wanyu zhang Jingyi WU guang YANG Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China

In order to clarify the effect of a buoyancy force on conduction–convection coupled heat transfer in a hollow cylinder, the flow and thermal characteristics were analyzed using an RNG k-ε turbulence model. The Reynolds number was fixed at 1.014 × 10^(6), and the Rayleigh number varied from 1.122 × 10^(10)to 1.088 × 10^(11). Results have shown that, when considering the effect of an opposed buoyancy force, increasing the Rayleigh number has a positive impact on the rate of change and uniformity of the cylinder temperature. The temperature distributions along the axial and circumferential directions are similar for different Rayleigh numbers, but extreme values *** the axial direction, the maximum temperature is obtained at the interface between the variable-diameter part and the constant-diameter part. The maximum dimensionless temperature value decreases to 0.12 when the Rayleigh number increases to 1.088 × 10^(11). Along the circumferential direction, the temperature distribution is affected by the buoyancy force, which results in the temperature of the upper part being higher than that of the lower part. After nondimensionalization of the temperature and time, a correlation was proposed to illustrate the transient heat transfer process quantitatively. The standard deviation of the maximum relative temperature, representing the temperature uniformity, was also calculated. It was found that the difference in the direction of the buoyancy force made a huge difference. Compared with the opposed buoyancy force, the maximum dimensionless temperature is almost two times higher with an assisted buoyancy force. Similarly, the heat transfer coefficient with an assisted buoyancy force is half of that with an opposed buoyancy force. Overall, an assisted buoyancy force plays a negative role in terms of thermal characteristics. The flow field around the hollow cylinder was also illustrated to reveal the mechanism of the buoyancy force on magnitude and direction aspects

关键词： Buoyancy Conduction-convection heat transfer Transient analysis Hollow cylinder Non-dimensionalization

Essential Players in Cooperative Games with Graph Communication Structure

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Journal of the Operations Research Society of China 2024年第1期12卷 93-108页

作者： guang zhang Jing-Yi Ge Business School University of Shanghai for Science and TechnologyShanghai200093China

A class of cooperative games with graph communication structure is studied in this paper by considering some important players,namely essential *** the assumption that only connected coalitions containing essential players are able to cooperate and obtain their worths,the class of graph games with essential players is proposed as well as an allocation *** proposed value follows the spirit of the Myerson value defined by applying the Shapley value on a modified *** properties,feasible component efficiency,the inessential component property,and fairness,are provided to fully characterize this value,where feasible component efficiency and fairness follows the same ideas of component efficiency and fairness for classical graph games,and the inessential component property says that the total payoffs of the players in a non-feasible component is ***,some computational aspects of the proposed value and comparisons with disjunctive permission value for games with permission structure are also studied,respectively.

关键词： Cooperative game Graph structure Essential player Myerson value Computation Permission structure