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A novel medium-entropy(TiVNb)_(2)AlC MAX phase:Fabrication,microstructure,and properties

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Journal of Materials Science & Technology 2023年第6期137卷 91-99页

作者： Guangqi He Yi Zhang Pei Yao xingchao li Ke Ma Jun Zuo Meishuan li Changsheng liu Jingjun Xu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Science and Technology on Advanced Functional Composites Laboratory Aerospace Research Institute of Material and Processing TechnologyBeijing 100076China

Medium-or high-entropy materials have great potential for applications due to their diverse compo-sitions and unexpected physicochemical ***,a novel medium-entropy(TiVNb)_(2)AlC was synthesized via hot pressing at 1400℃from three individual M_(2)AlC(M=Ti,V,Nb)MAX *** microstructure of(TiVNb)_(2)AlC was characterized from the microscale to the atomic scale by scanning electron microscope microscopy(SEM),scanning transmission electron microscopy(STEM),and energy dispersive spectroscopy(EDS).The results showed that Ti,V,and Nb atoms were fully solid-soluble in the M-sites of the M_(2)AlC MAX *** with three individual MAX phases,the thermal conduc-tivity of(TiVNb)_(2)AlC was reduced greatly in the temperature range of 293-1473 K,and its mechanical properties(including Young’s modulus,Vickers hardness,and bending strength)were all increased due to the solid solution strengthening and electronic mechanism.

关键词： Medium-entropy ceramics MAX phases Microstructure Thermal properties Mechanical properties

Research progress of microvascular development in bronchopulmonary dysplasia

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儿科学研究(英文) 2024年第4期08卷 299-312页

作者： Zhang Jiaxin Du Weiwei Zhang Zongli li Tao li xingchao Xi Shibing Department of Pediatrics Taihe Hospital Hubei University of Medicine Shiyan China Department of Pediatrics The Affiliated Wuxi People’s Hospital of Nanjing Medical University Wuxi China Institute of Pediatric Disease Taihe Hospital Hubei University of Medicine Shiyan China

Bronchopulmonary dysplasia (BPD) is a chronic lung disease that arises during the neonatal period, and its underlying mechanisms are still not fully understood. The disorder of microvascular development plays a significant role in the development of BPD. This article presents a comprehensive review of the advancements made in understanding the mechanisms and treatment approaches related to microvascular development in the pathogenesis of BPD.

关键词： Bronchopulmonary dysplasia Microvascular Therapy

Oxidation behavior of non-stoichiometric(Zr,Hf,Ti)C_(x) carbide solid solution powders in air

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Journal of Advanced Ceramics 2021年第4期10卷 741-757页

作者： Huilin LUN Yi ZENG Xiang XIONG Ziming YE Zhongwei ZHANG xingchao li Haikun CHEN Yufeng liU State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Science and Technology of Advanced Functional Composites Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

Multi-component solid solutions with non-stoichiometric compositions are characteristics of ultra-high temperature carbides as promising materials for hypersonic ***,for group IV transition-metal carbides,the oxidation behavior of multi-component non-stoichiometric(Zr,Hf,Ti)C_(x)carbide solid solution has not been clarified *** present work fabricated four kinds of(Zr,Hf,Ti)C_(x)carbide solid solution powders by free-pressureless spark plasma sintering to investigate the oxidation behavior of(Zr,Hf,Ti)C_(x)in *** effects of metallic atom composition on oxidation resistance were *** results indicate that the oxidation kinetics of(Zr,Hf,Ti)C_(x)are composition dependent.A high Hf content in(Zr,Hf,Ti)C_(x)was beneficial to form an amorphous Zr-Hf-Ti-C-0 oxycarbide layer as an oxygen barrier to enhance the initial oxidation ***,an equiatomic ratio of metallic atoms reduced the growth rate of(Zr,Hf,Ti)O_(2)oxide,increasing its phase stability at high temperatures,which improved the oxidation activation energy of(Zr,Hf,Ti)C_(x).

关键词： ultra-high temperature ceramics(UHTCs) (Zr,Hf,Ti)C_(x)carbides oxidation behavior oxidation resistance free-pressureless spark plasma sintering

CBERS-02 Application Assessment

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空间科学学报 2004年第Z1期24卷 46-59页

作者： GUO Jianning YU Jin MIN Xiangjun li xingchao HOU Minghui China Center for Resources Satellite Data and Application Beijing 100830 China China Center for Resources Satellite Data and Application Beijing 100830 China China Center for Resources Satellite Data and Application Beijing 100830 China China Center for Resources Satellite Data and Application Beijing 100830 China China Center for Resources Satellite Data and Application Beijing 100830 China

As the successor of CBERS-01, CBERS-02 was launched successfully on 21October 2003 and transmitted its first downlink data the next day. According to the OBT (On Board Test) outline, CRESDA cooperated with CAST and many remote sensing organizations in China in implementing the test of the satellite payloads, ground processing system and data application. In this paper, the test is briefly illustrated in three parts: Ⅰ. Satellite Parameters Test (especially the test for payloads), Ⅱ. Payload Image Quality Assessment, and Ⅲ. Data Application Assessment. The results of the test show that the image quality of CBERS-02 is much improved over CBERS-01 and will continue to play a more important role in the society and economic development of China.

关键词： CBERS-02, Application System, On Board Test

氧浓度变化对人肺动脉内皮细胞中ANGPTL8表达的影响

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基础医学与临床 2025年第1期45卷 12-19页

作者：张宗丽李涛马菁文张嘉鑫李兴朝席世兵十堰市太和医院(湖北医药学院附属医院)儿童疾病研究所湖北十堰442000 十堰市太和医院(湖北医药学院附属医院)儿科2病区湖北十堰442000 湖北医药学院药学院湖北十堰442000 湖北医药学院儿童疾病研究所湖北十堰442000

目的探讨氧浓度变化对肺动脉内皮细胞(HPAECs)中血管生成素样蛋白8(ANGPTL8)表达的影响,以及ANGPTL8在肺动脉高压(PH)中的作用和机制。方法低氧(1%)和高氧(85%)处理HPAECs,Western blot和PCR等检测ANGPTL8的表达,并分析内皮-间质转化(En... 详细信息

目的探讨氧浓度变化对肺动脉内皮细胞(HPAECs)中血管生成素样蛋白8(ANGPTL8)表达的影响,以及ANGPTL8在肺动脉高压(PH)中的作用和机制。方法低氧(1%)和高氧(85%)处理HPAECs,Western blot和PCR等检测ANGPTL8的表达,并分析内皮-间质转化(EndMT)及ERK信号通路的变化。同时,高氧处理新生大鼠,构建支气管肺发育不良(BPD)模型,观察肺组织中ANGPTL8蛋白表达及ERK信号通路的变化。结果低氧组HPAECs中ANGPTL8的蛋白表达显著升高,伴随ERK信号通路的抑制(P<0.05)。ANGPTL8促进低氧诱导的EndMT过程(P<0.05),沉默ANGPTL8可以部分逆转EndMT过程。高氧组HPAECs和大鼠肺组织中ANGPTL8蛋白表达降低,伴随ERK信号通路的激活(P<0.05)。结论HPAECs中ANGPTL8对氧浓度变化高度敏感,其表达的变化与ERK信号通路的活性状态密切相关,对PH的发展具有潜在的调控作用。

关键词：肺动脉高压血管生成素样蛋白8(ANGPTL8) 内皮-间质转化(EndMT) 低氧高氧

The Application Achievements And Perspective Of CBERS Series Satellite Imagery

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Aerospace China 2009年第1期10卷 10-14页

作者： li xingchao Qi Xueyong Lu Yilin China Center for Resources Satellite Data and Application

Since the first China-Brazil Earth Resources Satellite(CBERS-1), launched in 1999,the CBERS data has been applied in many fields *** social and economic benefits have been achieved. This article presents the application achievements during the past nine years, and gives a perspective for the *** these applications demonstrate that the CBERS data has been an important data source for resources investigation

关键词：中巴地球资源卫星应用卫星图像卫星系列展望卫星数据 CBERS 经济效益

Mechanism regulation over dual-atom catalyst enables high-performance oxidative alcohol esterification

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Science Bulletin 2025年第1期70卷 78-89页

作者： Ce liu Teng li xingchao Dai Jian Zhao liping Zhang Xinjiang Cui State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization State Key Laboratory for Oxo Synthesis and Selective OxidationLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The development of heterogeneous catalysts with well-defined uniform isolated or multiple active sites is of great importance for understanding catalytic performances and studying reaction ***,we present a CoCu dual-atom catalyst(CoCu-DAC)where bonded Co-Cu dual-atom sites are embedded in N-doped carbon matrix with a well-defined Co(OH)CuN_(6)*** CoCu-DAC exhibits higher catalytic activity and selectivity than the Co single-atom catalyst(Co-SAC)and Cu single-atom catalyst(CuSAC)counterparts in the catalytic oxidative esterification of alcohols and a variety of methyl and alkyl esters have been successfully *** studies reveal that the activation energy(29.7 kJ mol^(-1))over CoCu-DAC is much lower than that over Co-SAC(38.4 kJ mol^(-1))and density functional theory(DFT)studies disclose that two different mechanisms are regulated over CoCu-DAC and Co-SAC/Cu-SAC in three-step esterification of *** bonded Co-Cu and adjacent N species efficiently catalyze the elementary reactions of alcohol dehydrogenation,O2activation and ester formation,*** stepwise alkoxy pathway(O-H and C-H scissions)is preferred for both alcohol dehydrogenation and ester formation over CoCu-DAC,while the progressive hydroxylalkyl pathway(C-H and O-H scissions)for alcohol dehydrogenation and simultaneous hemiacetal dehydrogenation are favored over Co-SAC and *** peaks in the Fourier transform infrared spectroscopy analysis may confirm the formation of the metal-C intermediate and the hydroxylalkyl pathway over Co-SAC.

关键词： Dual-atom catalysts Oxidative esterification Mechanism regulation Alcohol

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空管新技术在低空空域管理中应用分析

电子测试 2015年第6X期26卷 126-127页

作者：李邢超民航局空管局运行管理中心北京100022

随着低空空域内航空器数量的不断增加,飞行科目和类型也不断呈现出多样化的趋势,这给低空空域管理带来了亲所谓有的考验。现有的低空空域管理手段中存在一系列问题,阻碍了我国航空事业的发展。除了需要进行体制方面的变革外,空管高新技... 详细信息

随着低空空域内航空器数量的不断增加,飞行科目和类型也不断呈现出多样化的趋势,这给低空空域管理带来了亲所谓有的考验。现有的低空空域管理手段中存在一系列问题,阻碍了我国航空事业的发展。除了需要进行体制方面的变革外,空管高新技术的引用是提升低空空域管理水平的重要方式,有利于实现低空空域的资源利用率达到最高,推动我国航空业的持续快速发展。

关键词：空管新技术低空空域管理

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红色金融视角的社会主义金融本质探究

征信 2021年第11期39卷 24-27页

作者：高杰英李兴超首都经济贸易大学北京100070

1921—1949年红色金融逐步从弱变强、从局部探索走向统一,并形成体系。在"为人民服务"的金融初心下,红色金融功能不断提升,金融管理不断完善。社会主义金融与红色金融一脉相承,其本质是"为人民服务"。现阶段表现为服务实体经济以满足人... 详细信息

1921—1949年红色金融逐步从弱变强、从局部探索走向统一,并形成体系。在"为人民服务"的金融初心下,红色金融功能不断提升,金融管理不断完善。社会主义金融与红色金融一脉相承,其本质是"为人民服务"。现阶段表现为服务实体经济以满足人民日益增长的美好生活需求,解决发展的不平衡、不充分问题。金融功能与效率的提升是实现金融初心的手段,改革开放与创新是金融初心的继续传承。

关键词：红色金融社会主义金融金融初心金融本质金融功能

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