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Spaceborne GPS receiver antenna phase center offset and variation estimation for the Shiy.n 3 satellite

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Chinese Journal of Aeronautics 2016年第5期29卷 1335-1344页

作者： Gu Defeng lai yuwang Liu junhong ju Bing Tu Jia College of Sciences National University of Defense Technology

In determining the orbits of low Earth orbit （LEO） satellites using spaceborne GPS, the errors caused by receiver antenna phase center offset （PCO） and phase center variations （PCVs） are gradually becoming a major limiting factor for continued improvements to accuracy. Shiy.n 3, a small satellite mission for space technology experimentation and climate exploration, was developed by China and launched on november 5, 2008. The dual-frequency GPS receiver payload delivers 1 Hz data and provides the basis for precise orbit determination within the range of a few centimeters. The antenna PCO and PCV error characteristics and the principles influencing orbit determination are analyzed. The feasibility of PCO and PCV estimation and compensation in different directions is demonstrated through simulation and in-flight tests. The values of receiver antenna PCO and PCVs for Gravity Recovery and Climate Experiment （GRACE） and Shiy.n 3 satellites are estimated from one month of data. A large and stable antenna PCO error, reaching up to 10.34 cm in the z-direction, is found with the Shiy.n 3 satellite. The PCVs on the Shiy.n 3 satellite are estimated and reach up to 3.0 cm, which is slightly larger than that of GRACE satellites. Orbit validation clearly improved with independent k-band ranging （KBR） and satellite laser ranging （SLR） measurements. For GRACE satellites, the average root mean square （RMS） of KBR residuals improved from 1.01 cm to 0.88 cm. For the Shiy.n 3 satellite, the average RMS of SLR residuals improved from 4.95 cm to 4.06 cm.

关键词： GRACE Phase center offset Phase center variations Shiy.n 3 Spaceborne GPS

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高校科技成果转化相关法律风险实证分析

西南科技大学学报（哲学社会科学版） 2024年第2期41卷 75-81页

作者：赖举侯泽福阚俊西南科技大学后勤与产业管理处四川绵阳621010 西南科技大学法学院四川绵阳621010

我国高校作为科技创新的重要供给主体,在国家法律法规激励下同时也是科技成果转化的主力军,然而我国高校科技成果转化率却不容乐观。影响高校科技成果转化率的因素众多,其中法律风险处于重要地位。本文抓住高校科技成果的知识产权属性,... 详细信息

我国高校作为科技创新的重要供给主体,在国家法律法规激励下同时也是科技成果转化的主力军,然而我国高校科技成果转化率却不容乐观。影响高校科技成果转化率的因素众多,其中法律风险处于重要地位。本文抓住高校科技成果的知识产权属性,从知识产权的确权、交易、保护过程入手,以目前我国高校存在的转化模式以及具体的转化方式为着力点,对其中存在的法律风险进行分析,主要得出三个方面的法律风险:权属分割过程中的知识产权法律风险、价值评估过程中的知识产权法律风险和高校科技成果保护过程中的知识产权法律风险。最后,提出相关对策,包括:明确高校科技成果所有权归属及分割比例、选择适当的价值评估方式、建立健全本单位技术秘密保护制度等。

关键词：科技成果转化权属分割价值评估

机制砂与特细砂抗氯盐侵蚀混凝土的制备及性能研究

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硅酸盐通报 2024年第6期43卷 2121-2129页

作者：汪伟赖增成谭鹏鞠志成杨海成范志宏中交四航工程研究院有限公司水工构造物耐久性技术交通行业重点实验室广州510230 中国路桥工程有限责任公司北京100011 中交集团建筑材料重点实验室广州510230

利用机制砂、特细砂等制备抗氯盐侵蚀混凝土对降低生产成本、提升桥梁服役寿命具有重要意义。本研究通过优化骨料设计与水泥浆体组成提升混凝土的抗氯离子侵蚀性能,研究了骨料级配、特细砂用量、砂率、水胶比、胶凝材料种类对混凝土性... 详细信息

利用机制砂、特细砂等制备抗氯盐侵蚀混凝土对降低生产成本、提升桥梁服役寿命具有重要意义。本研究通过优化骨料设计与水泥浆体组成提升混凝土的抗氯离子侵蚀性能,研究了骨料级配、特细砂用量、砂率、水胶比、胶凝材料种类对混凝土性能的影响。结果表明:8~16 mm碎石质量分数由50%增加至80%时,氯离子扩散系数由4.0×10^(-12)m^(2)/s降低至2.9×10^(-12)m^(2)/s;特细砂替代50%(质量分数)机制砂时,氯离子扩散系数为3.6×10^(-12)m^(2)/s,仍可以满足设计要求;砂率增大,氯离子扩散系数先减小后增大。水胶比在0.36~0.38时,氯离子扩散系数低于3.5×10^(-12)m^(2)/s;矿渣组分水化改善了混凝土的孔结构,并形成了更多的AFm、C-S-H产物,提升了混凝土对氯离子的固化能力,矿渣水泥混凝土氯离子扩散系数较普通硅酸盐水泥混凝土降低了40%。

关键词：机制砂特细砂矿渣水泥抗氯盐侵蚀氯离子扩散系数力学性能

A Z/E isomeric cation designed organic-inorganic cadmium chloride ferroelectric with broadband white-light emission

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Science China Chemistry 2024年

作者： jun-Chao Qi y.n Qin Hang Peng Hui-Peng Lv y.ng-ju Bai Xin Shen Zhang-Tian Xia Wei-Qiang Liao Ordered Matter Science Research Center Nanchang University

Hybrid organic-inorganic metal halides（HOMHs） have attracted tremendous interest in the past decades due to their diverse functional properties, such as ferroelectricity and luminescence. However, although a large number of ferroelectric HOMHs and luminescent HOMHs have been reported, the HOMH ferroelectrics with white-light emission remain very sparse. Here, for the first time, by using the Z/E isomeric organic cation, we designed a cadmium-based HOMH ferroelectric [EE-PMU]CdCl4（EEPMU = pyridin-2-ylmethanamide muconate） with broadband white-light emission. In contrast to the [ZZ-PMU]CdCl4with centrosymmetric crystal structure at room temperature, [EE-PMU]CdCl4adopts the polar crystal symmetry, which shows piezoelectricity with a piezoelectric coefficient of d33up to 19 pC/n and ferroelectricity with the saturated polarization of 1.52μC/cm2. Moreover, [EE-PMU]CdCl4exhibits a broadband white-light emission with an ultra-high color rendering index of 91 under UV excitation, which is related to the severely distorted [CdCl4]2-tetrahedron in the structure. To our knowledge, [EEPMU]CdCl4is the first example of Z/E isomeric cation-designed HOMH ferroelectric and the first cadmium halide white-light emissive ferroelectric. This finding paves a new way for the design of organic-inorganic molecular ferroelectrics with white-light emission.

关键词：

Ore-forming Fluid Characteristics of the Saishitang Cu-polymetallic Deposit in Qinghai Province,China

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 485-504页

作者： lai Jianqing ju Peijiao MAO y.n An Jianghua WAnG Xiongjun Key Laboratory of Metallogenic Prediction of nonferrous Metals Ministry of EducationCentral South University School of Geosciences and Info-Physics Central South University

Saishitang Cu-polymetallic deposit is located in the southeast section of Late Paleozoic arcfoid in the southeastern margin of Qaidam platform. Accoring to the geological process of the deposit, four mineralization episodes were identified： melt/fluid coexisting period （O）, skarn period （A）, first sulfide period （B） and second sulfide period （C）, and 10 stages were finally subdivided. Three types of inclusions were classified in seven stages, namely crystal bearing inclusions （type I）, aqueous inclusions （type Ⅱ） and pure liquid inclusions （type Ⅲ）. Type I and Ⅱ inclusions were observed in stage O1, having homogenization temperature from 252 to 431℃, and salinities ranging from 24.3% to 48.0%. Type I inclusion was present in stage A1, having homogenization temperature from 506 to 548℃, and salinities ranging from 39.4% to 44.6%. In stage B1, type Ⅱ and Ⅲ inclusions were observed, with homogenization temperature concentrating between 300-400℃, and salinities from 0.4% to 4.3%. Type II inclusions were present in stage B2, with homogenization temperature vary.ng from 403 to 550℃. In stage C1, type I and II inclusion commonly coexisted, and constituted a boiling inclusion group, having homogenization temperatures at 187-463℃, and salinities in a range of 29.4%-46.8% and 2.2%-11.0%. Type II and III inclusions were developed in stage C2, having homogenization temperature at 124-350℃, and salinities ranging between 1.6% and 15.4%. In stage C3, type Ⅱ and Ⅲ inclusions were presented, with a homogenization temperature range of 164-360℃, and salinities vary.ng from 4.0% to 11.0%. The results of micro-thermal analysis show that fluids are characterized by high temperature and high salinity in stage O1 and A1, and experienced slight decrease in temperature and dramatic decrease in salinity in stage B1 and B2. In stage C1, the salinity of fluid increased greatly and a further decrease of temperature and salinity occurred in stage C2 and C3. Fluids boiled in stage C1. With calcul

关键词： fluid inclusions ore-forming fluid Laser Raman Spectroscopy Saishitang Qinghai Province

Effect of Ultraviolet Radiation on Hsp70 Protein Expression in HaCaT Cells

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World Journal of nuclear Science and Technology 2024年第1期14卷 59-71页

作者： Sergio Hugo Sánchez Rodríguez Jesús Rodríguez Vergil Manuel Venancio Muñoz juárez Kevin Said Ramírez Dávila Luis Martín García Ortiz Germán Flores Cortés Luz Elena Vidales Rodríguez Jesús Adrián López David Alejandro García López Laboratorio de Biología Celular y.neurobiología Unidad Académica de Ciencias Biológicas Universidad Autónoma de Zacatecas Zacatecas México Laboatorio de Bacterias y Hongos Filamentosos Unidad Académica de Ciencias Biológicas Universidad Autónoma de Zacatecas Zacatecas México Laboratorio de MicroRnAs Unidad Académica de Ciencias Biológicas Universidad Autónoma de Zacatecas Zacatecas México

Ultraviolet radiation by its wavelength is divided into: UVA, UVB and UVC. Only UVA and UVB manage to penetrate the ozone layer, but due to anthropological activities, all of them are capable of interacting with humans to a greater or lesser extent, and can generate adverse effects such as cellular stress when interacting with intra-and extracellular biomolecules. The skin is the first organ in contact with UV radiation, and the stress it generates can be analyzed by the expression of a bioindicator of cellular damage such as Hsp70. Therefore, the objective of the project was: to determine the effect of UVA, UVB and UVC radiation on HaCaT epithelial cells, by analyzing the expression of Hsp70. Materials and methods: HaCaT cells were cultured in vitro, which were irradiated with UVA, UVB and UVC light at different doses, to subsequently determine the degree of Hsp70 expression by Immunodetection by PAGE-SDS and Western Blot. Results: Basal expression of Hsp70 was observed in no irradiated HaCaT cells. When HaCaT cells were irradiated with UVA, UVB, UVC, an increase in this Hsp70 protein was observed. With UVA, a higher degree of expression was observed at a time of 30 minutes of irradiation. With UVB the highest expression shifted to a time of 20 minutes. With UVC, overexpression was observed after 10 minutes. Conclusion: UV radiation generates cellular stress on HaCaT cells, evaluated by the stress bioindicator Hsp70. According to the wavelength of UV radiation, those that have a shorter wavelength have a greater potential for cellular damage, such as UVC.

关键词： Ultraviolet A Light (UVA) Ultraviolet B Light (UVB) Ultraviolet C Light (UVC) Heat Shock Protein 70 (Hsp70) HaCaT

Atomic-scale roles of Zn element in age-hardened AlMgSiZn alloys

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Journal of Materials Science & Technology 2021年第11期70卷 105-112页

作者： n.n.Jiao y.X.lai S.L.Chen P.Gao J.H.Chen Center for High-Resolution Electron Microscopy College of Materials Science&EngineeringHunan UniversityChangsha410082China Electron Microscopy Laboratory and International Center for Quantum Materials School of PhysicsPeking UniversityBeijing100871China

Adding alloy.ng elements to improve the performances or the manufacturing processes of Al-Mg-Si alloys has long been a serious issue in developing advanced automotive aluminum *** Zn element,among those promising ones,has demonstrated positive alloy.ng effects on Al-Mg-Si ***,the atomic-scale roles of Zn in an age-hardened Al-Mg-Si-Zn alloy have not been adequately *** atomic-resolution electron microscopy,here we report the precise locations of Zn elements in all hardening precipitates involved and their alloy.ng mechanism at the atomic scale when alloy.ng the *** results show that Zn atoms enter all the major hardening phases to occupy specific featured atomic sites of the original elements,*** Si1 and Mg2 sites in theβ’-2 phase,and modify their crystal structures,interfacial structures and morphologies in characteristic *** is revealed that for theβ’-phase,Zn atoms occupy unique atomic sites,whereas for other phases,they demonstrate similar behaviors as other additive alloy.ng elements such as Ag and Cu do.

关键词： Al-Mg-Si alloy Zn addition Precipitate Electron microscopy

基于课程思政理念混合式教学在护理学导论课程中的应用研究

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智慧健康 2024年第1期10卷 154-159页

作者：惠静周菊邓清红来平英四川护理职业学院基础护理教研室四川成都610199

目的探讨基于课程思政理念混合式教学在护理学导论课程中的应用效果。方法选取某高校大专护理学专业大一2个班级学生为研究对象。采用抛硬币方式,将一个班作为干预组(n=49),另一个班作为对照组(n=50)。对照组采用传统教学模式,干预组采... 详细信息

目的探讨基于课程思政理念混合式教学在护理学导论课程中的应用效果。方法选取某高校大专护理学专业大一2个班级学生为研究对象。采用抛硬币方式,将一个班作为干预组(n=49),另一个班作为对照组(n=50)。对照组采用传统教学模式,干预组采用基于课程思政理念混合式教学。课程结束后比较两组研究对象的职业认同感得分和学业自我效能感得分。结果干预组的职业认同感得分(t=3.486,P<0.05)和学业自我效能感得分(t=3.051,P<0.05)均高于对照组。结论将基于课程思政理念混合式教学应用于护理学导论课程中,能够有效提高护生的职业认同感和学业自我效能感。

关键词：课程思政护理学导论混合式教学职业认同学业自我效能

m^(6)A reader yTHDF1 promotes cardiac fibrosis by enhancing AXL translation

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Frontiers of Medicine 2024年第3期18卷 499-515页

作者： Han Wu Weitao Jiang Ping Pang Wei Si Xue Kong Xinyue Zhang yuting Xiong Chunlei Wang Feng Zhang Jinglun Song y.ng y.ng Linghua Zeng Kuiwu Liu y.ngqiong Jia Zhuo Wang Jiaming ju Hongtao Diao yu Bian Baofeng y.ng Department of Pharmacology.national Key Laboratory of Frigid Zone Cardiovascular Diseases the State-Province Key Laboratories of Biomedicine-Pharmaceutics of ChinaKey Laboratory of Cardiovascular ResearchMinistry of Education)College of PharmacyHarbin Medical UniversityHarbin150081China

Cardiac fibrosis caused by ventricular remodeling and dysfunction such as post-myocardial infarction(MI)can lead to heart *** n6-methyladenosine(m^(6)A)methylation has been shown to play a pivotal role in the occurrence and development of many *** investigating the biological function of the m^(6)A reader yTHDF1 in cardiac fibrosis,adeno-associated virus 9 was used to knock down or overexpress the yTHDF1 gene in mouse hearts,and MI surgery in vivo and transforming growth factor-β(TGF-β)-activated cardiac fibroblasts in vitro were performed to establish fibrosis *** results demonstrated that silencing yTHDF1 in mouse hearts can significantly restore impaired cardiac function and attenuate myocardial fibrosis,whereas yTHDF1 overexpression could further enhance cardiac dysfunction and aggravate the occurrence of ventricular pathological remodeling and fibrotic ***,zinc finger BED-type containing 6 mediated the transcriptional function of the yTHDF1 gene ***1 augmented AXL translation and activated the TGF-β-Smad2/3 signaling pathway,thereby aggravating the occurrence and development of cardiac dysfunction and myocardial ***,our data indicated that yTHDF1 was involved in activation,proliferation,and migration to participate in cardiac fibrosis in *** results revealed that yTHDF1 could serve as a potential therapeutic target for myocardial fibrosis.

关键词： cardiac fibrosis yTHDF1 AXL ZBED6 heart failure