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Comparative Study of 3D-Printed Porous Titanium Alloy with Rod Designs of Three Different Geometric Structures for Orthopaedic Implantation

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 54-66页

作者： jiaxin Li Haozhang Zhong Bojun Cao Zhaoyang ran jia Tan Liang Deng Yongqiang Hao Jinglong Yan Department of Orthopedics The Second Affiliated Hospital of Harbin Medical UniversityHarbin150001China Shanghai Engineering Research Center of Innovative Orthopaedic Instruments and Personalized Medicine Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai200011China Institute of Materials Modification and Modeling Shanghai Jiao Tong UniversityShanghai200240China

Porous titanium alloy is currently widely used in clinical treatment of orthopaedic diseases for its lower elastic modulus and ability to integrate with bone *** the micro-level,cells can respond to different geometries,and at the macro-level,the geometric design of implants will also affect the biological function of *** this study,three kinds of porous scaffolds with square,triangular and circle rod shapes were designed and 3D *** study observed the proliferation and differentiation of MC3T3-E1 cells during surface culture of the three types of *** also evaluated the characteristics of the three scaffolds by means of compression tests and scanning electron microscopy to provide a reference for the design of porous titanium alloy implants for clinical *** trends of cell proliferation and gene expression between the three types of scaffolds were observed after treatment with two *** results show that the square rod porous scaffolds have the best proliferative and osteogenic activities,and these findings may be due to differences in piezo-type mechanosensitive ion channel component 1(Piezo1)and Yes-associated protein(YAP)expression caused by the macro-geometric topography.

关键词： Porous titanium scaffolds Geometric morphology Cell proliferation Structural design

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A Class of m-Complex Symmetric Operators on Hardy Space

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Journal of Mathematical Research with Applications 2024年第1期44卷 63-80页

作者： jia FU Xinmei LI ran LI School of Mathematics Liaoning Normal University

In this paper,we study the necessary and sufficient condition that the Toeplitz operators with respect to the conjugations of one permutation are 2-complex ***,we introduce a class of conjugations called the conjugations of one permutations on the classical Hardy ***,Toeplitz operators are completely characterized as 2-complex symmetric structure under this class of *** matrix representation of Toeplitz operators in the classical regular orthogonal basis on Hardy space is used to describe this class of 2-complex symmetric Toeplitz ***,we add two preconditions fn=-f-nand fn=f-nrespectively to the Toeplitz operators,and we get more simplified *** the second condition,we study the 3-complex symmetry of Toeplitz operators,and we get the same result for Tfis a 3-CSO with the conjugation C((i,j)) and 2-CSO’s.

关键词： m-complex symmetric operator Toeplitz operator Hardy space

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干涉测量数据采集设备时延的温度效应

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时间频率学报 2024年第1期47卷 54-61页

作者：郭鹏嵩韦沛马浪明王伟贾浩然杨旭海中国科学院国家授时中心西安710600 中国科学院大学北京100049

干涉测量是一种被动测量手段,是目前角分辨率最高的天文观测手段,且不占用星上资源,广泛应用于天文学、测地学和深空导航领域。提高干涉测量的一个重要途径是精确测定干涉测量仪器的系统误差,数据采集设备时延是其重要组成部分,目前干... 详细信息

干涉测量是一种被动测量手段,是目前角分辨率最高的天文观测手段,且不占用星上资源,广泛应用于天文学、测地学和深空导航领域。提高干涉测量的一个重要途径是精确测定干涉测量仪器的系统误差,数据采集设备时延是其重要组成部分,目前干涉测量的时延测定精度可达到亚纳秒级水平,对设备时延有更高的精度要求。本文利用实际观测的数据研究数据采集设备的设备时延,分析室内温度、设备温度与该设备时延的相关性,建立设备时延与设备温度之间的数学模型,并对设备时延进行修正。试验结果表明:该数据采集设备的设备时延变化与设备温度呈线性关系,通过本文方法修正后,在温度控制单元没有开启情况下(设备温度变化大),精度改善可达60%以上,温度控制单元开启情况下(设备温度变化不大),精度也会有所改善,达10%左右。

关键词：干涉测量设备时延温度系数

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某数据中心基础设施节能技术应用及分析

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电信工程技术与标准化 2024年第5期37卷 73-76页

作者：赵航宇何庞贾然陆恩波王招辉高鑫中移系统集成有限公司石家庄050000 中国移动通信集团贵州有限公司贵阳550000

为探究数据中心高能耗的有效解决方案,本文以某数据中心基础设施建设和运行维护过程中应用的先进节能技术和方法为例进行分析讨论,建议数据中心全生命周期从服务理念、基础设施系统、运维保障工具、运维组织架构和运维技术5个方向构建... 详细信息

为探究数据中心高能耗的有效解决方案,本文以某数据中心基础设施建设和运行维护过程中应用的先进节能技术和方法为例进行分析讨论,建议数据中心全生命周期从服务理念、基础设施系统、运维保障工具、运维组织架构和运维技术5个方向构建起一套节能服务体系。数据中心建设和运行维护期建议采用高压直流的供电模式,采用水冷系统架构,部署动环监控和冷水自控系统等,尤其重点关注温水制冷和顶置空调技术的应用。

关键词：数据中心高能耗节能

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Observation and Analysis of Meteorological Conditions for Icing of Wires in Guizhou, China

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Journal of Geoscience and Environment Protection 2019年第9期7卷 214-230页

作者： Jifen Wen ran jia Yuxiang Peng Guizhou Provincial Office of Weather Modification Guiyang China Key Laboratory of Atmospheric Physics and Atmospheric Environment Nanjing University of Information Science & Technology Nanjing China

Icing of wires is a product of rain, fog, and freezing rain, and is a common meteorological disaster in winter in Guizhou Province of China. It is extremely harmful to facilities such as power transmission and communication lines, and has caused huge economic loss up to 48.9566 billion dollars a year. Based on the meteorological records of Guizhou from 1967, we analyze the meteorological characteristics during the icing of wires, and obtain the temperature, wind speed and direction conditions of the ice accident. The icing of wires is carried out by supercooling raindrops, freezing of the clouds, freezing and spreading on the wires. Different types of supercooled raindrops and cloud freezing and freezing processes will form different types of ice accretion;wind direction and wind speed will affect the growth of ice accretion by changing the speed of sub-cooling raindrops and cloud falling. The weight of rain-type ice accretion is between 24 and 152 g, and the weight of smog-type ice is between 40 - 76 g. The average ice density of these two places can be calculated to be 0.2 - 0.5 g/cm3. The longer the icing of wires, the higher the ice disaster rate.

关键词： Rain Smog Icing of Wires Weather Conditions

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闭孔泡沫铝泊松比及三轴压缩变形模式

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力学学报 2021年第8期53卷 2289-2297页

作者：贾然赵桂平西安交通大学航天航空学院机械结构强度与振动国家重点实验室西安710049

在闭孔泡沫铝的唯象本构模型中,泊松比是一个非常关键的参数,为了探究闭孔泡沫铝泊松比变化规律研究结果存在分歧的原因,认识闭孔泡沫铝泊松比变化规律中特征点的物理意义,采用数值模拟方法,建立了闭孔泡沫铝的3D-Voronoi模型及2D-Voro... 详细信息

在闭孔泡沫铝的唯象本构模型中,泊松比是一个非常关键的参数,为了探究闭孔泡沫铝泊松比变化规律研究结果存在分歧的原因,认识闭孔泡沫铝泊松比变化规律中特征点的物理意义,采用数值模拟方法,建立了闭孔泡沫铝的3D-Voronoi模型及2D-Voronoi模型,对模型进行侧面位移耦合单轴压缩边界条件下的仿真分析;基于闭孔泡沫铝本构模型的唯象特性,对闭孔泡沫铝变形模式的研究同样十分重要,为明确其三轴压缩下的变形模式,对闭孔泡沫铝的3D-Voronoi模型进行侧面位移受限轴向压缩边界条件下的仿真分析.研究结果表明,常规壳单元接触中的厚度减薄特性是闭孔泡沫铝泊松比变化规律的研究结论存在分歧的原因,但厚度减薄不影响泡沫铝模型致密前胞孔结构的变形模式;闭孔泡沫铝泊松比的准确变化规律为"增高-降低-再增高"的"S"型曲线,并且,曲线极大值对应闭孔泡沫铝吸能效率的增速下降点;等比压缩应力状态下,闭孔泡沫铝存在四种侧面变形模式,分别为"(短期)压缩变形→膨胀变形"、"压缩变形→膨胀变形→压缩变形→膨胀变形"、"压缩变形→(短期)膨胀变形"及"压缩变形".

关键词：闭孔泡沫铝 Voronoi模型泊松比等比压缩变形模式

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泡沫铝本构行为研究进展

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力学学报 2020年第3期52卷 603-622页

作者：贾然赵桂平西安交通大学航天航空学院机械结构强度与振动国家重点实验室西安710049

作为泡沫金属的典型代表,泡沫铝是一种集结构性和功能性于一体的新型材料,随着生产工艺的提高及国民经济的发展,泡沫铝在航空航天、交通运输、建筑工程、机械制造等领域的应用日趋深入和广泛.工程中复杂的载荷工况,对泡沫铝本构模型的... 详细信息

作为泡沫金属的典型代表,泡沫铝是一种集结构性和功能性于一体的新型材料,随着生产工艺的提高及国民经济的发展,泡沫铝在航空航天、交通运输、建筑工程、机械制造等领域的应用日趋深入和广泛.工程中复杂的载荷工况,对泡沫铝本构模型的准确性及实用性提出了更高的要求.国内外学者对泡沫铝进行了大量的试验研究及有限元数值分析工作,随着各种研究和数值分析本构模型的提出、验证及修正等,人们对泡沫铝的力学性能及其应用的认识逐渐提高.本文首先简要概述了泡沫铝力学性能的试验研究及有限元数值分析的进展,然后重点综述泡沫铝本构行为的国内外研究进展及现状.最后,针对目前存在的问题,讨论并展望了泡沫铝本构行为的研究发展趋势.完善本构模型表征所需的特征参量,将各向异性或横观各项同性材料假定引入模型构建体系,明确静水压缩响应及单轴压缩响应在材料强化中的权重,建立例如随动强化般更加真实且准确反映泡沫铝强化过程的强化准则,将应变率效应研究成果引入本构模型中等是现有泡沫铝本构模型体系中的重要研究方向.

关键词：泡沫铝本构模型试验有限元

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Bilayer Compounded Polytetrafluoroethylene Membrane for Enhanced Oil-Water Emulsion Separation

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Chinese Journal of Polymer Science 2024年第6期42卷 838-850页

作者： Yu-Liang Yang Tai-ran Zhang Yan-Ting Han Shao-Yun Guo Qin-Gong Rong jia-Bin Shen State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyChengdu610065China West China Hospital/West China School of Nursing Sichuan UniversityChengdu610041China Shandong Senrong New Materials Co. Ltd.Zibo256401China

In order to achieve efficient and durable oil-water emulsion separation,the membranes possessing high separation efficiency and mechanical strength attract extensive attention and are in great *** present study,a kind of polytetrafluoroethylene(PTFE)-based bilayer membrane was fabricated by electrospinning fibrous PTFE(fPTFE)on an expanded PTFE(ePTFE)*** morphological observation revealed that the fibrous structure of the fPTFE layer could be tailored by controlling the formulation of spinning *** addition of appropriate polyoxyethylene(PEO)would make the fibers in the fPTFE layer finer and more *** a result,the compounded membrane exhibited a small pore size of approximately 1.25µm and a substantial porosity nearing 80%.This led to super-hydrophobicity,characterized by a high water contact angle(WCA)of 149.8°,and facilitated rapid oil *** water-in-oil emulsion separation experiment further confirmed that the compounded membrane not only had a high separation efficiency closing 100%,but such an outstanding separation capacity could be largely retained,either through multiple cycles of use or through strong acid(pH=1),strong alkali(pH=12),or high-temperature(100°C)***,the mechanical behavior of the bilayer membrane was basically contributed by that of each layer in terms of their volume *** significantly,the poor creep resistance of fPTFE layer was suppressed by compounding with ePTFE ***,this study has laid the groundwork for a novel approach to create PTFE-based compounded membranes with exceptional overall characteristics,showing promise for applications in the realm of emulsion separation.

关键词： ePTFE Electrospinning membrane Bilayer compounding Emulsion separation

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Correlation between liquid structure and glass forming ability in glassy Ag-based binary alloys

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 399-404页

作者： Lü XiaoQian, BIAN XiuFang, XIANG Nan & jia ran Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061, China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Jinan China

The atomic structures of liquid Ag-based binary alloys have been investigated in the solidification process by means of X-ray diffraction. The results of liquid structure show that there is a break point in the mean nearest neighbor distance r1 and the coordination number Nmin for glass-forming liquid, while the correlation radius rc and the coordination number Nmin display a monotone variational trend above the break point. It means glass-forming liquids have a steady changing in structure above liquidus and more inhomogeneous state at liquidus. We conclude that there is a strong correlation between liquid structure and glass forming ability in Ag-based binary alloys.

关键词： liquid structure glass forming ability Ag-based binary alloys

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Synthesis, Crystal Structure and Biological Activity of 2-(3,4-Dichloroisothiazol-5-yl)-4-(trifluoromethyl)-4,5-dihydrothiazol-4-yl-3-methylbenzoate

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Chinese Journal of Structural Chemistry 2015年第6期34卷 871-878页

作者： ZONG Guang-Ning LI Feng-Yun FAN Zhi-Jin MAO Wu-Tao SONG Hai-Bin CHEN Lai ZHU Yu-Jie XU Jing-Hua SONG Yin-Qi WANG jia-ran State Key Laboratory of Elemento-organic Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Nankai University College of Chemistry and Pharmacy Engineering Nanyang Normal University

The title compound diethyl 2-（3,4-dichloroisothiazol-5-yl）-4-（trifluoromethyl）-4,5- dihydrothiazol-4-yl-3-methylbenzoate （C15H9C12F3N202S2, Mr = 441.26） was prepared from methyl 3,4-dichloroisothiazole-5-carboxylate as the starting material by four steps of reaction. Its structure was characterized by IR, 1H-NMR, 13C-NMR, EA and single-crystal X-ray diffraction. The crystal of the title compound belongs to the monoclinic system, space group P2dc with a = 8.8437（18）, b = 16.128（3）, c = 12.305（3） A, β = 91.68（3）°, V= 1754.4（6） A3, Z = 4, Dc = 1.671 g/cm3,μ（MoKa） = 0,71073 mm^-1, F（000） = 888, R = 0.0384 and wR = 0.0778. Weak π-π interactions occur between the isothiazole rings and phenyl rings of adjacent molecules to form a one-dimensional chain and stabilize the crystal structure. Bioassay indicates that the title compound has good activity against the fungi and TMV tested.

关键词： isothiazole 4,5-dihydrothiazole synthesis crystal structure biological activity

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