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Adsorption and Decomposition of NH3 on Ni/Pt（111） and Ni/WC（001） Surfaces： A First-Principles Study

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Chinese Journal of Chemical Physics 2016年第6期29卷 710-716,I0002页

作者： Ai-ai Shen Yi-lin cao Schoolof:ChemistryandChemicalEnEineerin~.HenanNormalUniversity.Xinxi~n~453007.China

Density functional theory was used to study the NH3 behavior on Ni monolayer covered Pt（111） and WC（001）. The electronic structure of the surfaces, and the adsorption and decomposition of NH3 were calculated and compared. Ni atoms in the monolayer behave different from that in Ni（111）. More dz2 electrons of Ni in monolayer covered systems were shifted to other regions compared to Ni（111）, charge density depletion on this orbital is crucial to NH3 adsorption. NH3 binds more stable on Ni/Pt（lll） and Ni/WC（001） than on Ni（111）, the energy barriers of the first N-H bond scission were evidently lower on Ni/Pt（111） and Ni/WC（001） than on Ni（111）, these are significant to NH3 decomposition. N recombination is the rate-limiting step, high reaction barrier implies that N2 is produced only at high temperatures. Although WC has similar properties to Pt, differences of the electronic structure and catalytic activities are observed for Ni/Pt（111） and Ni/WC （001）, the energy barrier for the rate-determined step increases on Ni/WC（001） instead of decreasing on Ni/Pt（lll） when compared to Ni（111）. the N recombination barrier by modifying To design cheaper and better catalysts, reducing Ni/WC（001） is a critical question to be solved.

关键词： Ni monolayer Electronic structure NH3 decomposition Density functionaltheory

Flight control for air-breathing hypersonic vehicles using linear quadratic regulator design based on stochastic robustness analysis

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Frontiers of Information Technology & Electronic Engineering 2017年第7期18卷 882-897页

作者： lin cao Shuo TANG Dong ZHANG College of Astronautics Northwestern Polytechnical University Xi 'an 710072 China Shaanxi Aerospace Flight Vehicle Design Key Laboratory Xi 'an 710072 China

The flight dynamics model of air-breathing hypersonic vehicles （AHVs） is highly nonlinear and multivariable cou- pling, and includes inertial uncertainties and external disturbances that require strong, robust, and high-accuracy controllers. In this paper, we propose a linear-quadratic regulator （LQR） design method based on stochastic robustness analysis for the longitudinal dynamics of AHVs. First, input/output feedback linearization is used to design LQRs. Second, subject to various system parameter uncertainties, system robustness is characterized by the probability of stability and desired performance. Then, the mapping rela- tionship between system robustness and LQR parameters is established. Particularly, to maximize system robustness, a novel hybrid particle swarm optimization algorithm is proposed to search for the optimal LQR parameters. During the search iteration, a Chernoff bound algorithm is applied to determine the finite sample size of Monte Carlo evaluation with the given prohabilily levels. Finally, simulation results show that the optimization algorithm can effectively find the optimal solution to the LQR parameters.

关键词： Air-breathing hypersonic vehicles (AHVs) Stochastic robustness analysis linear-quadratic regulator (LQR) Par- ticle swarm optimization (PSO) Improved hybrid PSO algorithm

CT定量参数联合NLR与COPD合并Ⅱ型呼吸衰竭患者肺功能的相关性及预测预后的价值

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放射学实践 2024年第8期39卷 1040-1044页

作者：林幽草施晓瑜黄芳陈云峰林亚兰福建医科大学附属第二医院CT室福建泉州362000 福建医科大学附属第二医院呼吸科福建泉州362000

目的:探讨CT定量参数联合中性粒细胞/淋巴细胞比值(NLR)与慢性阻塞性肺疾病(COPD)合并Ⅱ型呼吸衰竭患者肺功能的相关性及预后预测价值。方法:将2021年1月-2022年12月在本院诊治的122例COPD合并II型呼吸衰竭患者作为研究对象。治疗前所... 详细信息

目的:探讨CT定量参数联合中性粒细胞/淋巴细胞比值(NLR)与慢性阻塞性肺疾病(COPD)合并Ⅱ型呼吸衰竭患者肺功能的相关性及预后预测价值。方法:将2021年1月-2022年12月在本院诊治的122例COPD合并II型呼吸衰竭患者作为研究对象。治疗前所有患者行1.0 mm薄层胸部CT扫描,使用Philips IntelliSpacePortal工作站内的COPD软件,测量并记录肺总容量、肺气肿容量、最大吸气末容积(MIV)、最大呼气末容积(MEV),并计算肺体积百分比(LVP)。对患者血液内的中性粒细胞和淋巴细胞浓度进行检测,计算并记录两者的比值(NLR)。采用耶格肺功能检测仪对患者的肺功能进行评估,记录用力肺活量(FVC)和一秒用力呼气容积(FEV1)。观察患者自入院治疗起90天内是否发生难以纠正的呼吸衰竭、心绞痛、心肌梗死、心力衰竭、心源性猝死、多脏器功能障碍及死亡等不良事件,将患者分为预后不良组和预后良好组。采用t检验方法比较2组间CT定量参数及NLR的差异,应用Pearson相关性分析评估CT定量参数、NLR与肺功能指标的相关性,采用受试者工作特征(ROC)曲线评估CT定量参数和NLR在患者预后预测中的效能。结果:MIV、MEV、NLR分别与FVC、FEV1呈负相关(P均0.05)。预后良好者89例,预后不良者33例。预后良好组的MIV、MEV和NLR显著低于预后不良组,差异均有统计学意义(P0.05)。CT定量参数(MIV、MEV)及NLR预测患者COPD合并II型呼吸衰竭患者预后的AUC分别为0.709(95%CI:0.601~0.816)、0.820(95%CI:0.744~0.895)和0.895(95%CI:0.825~0.965),三者联合预测患者预后的AUC达0.935(95%CI:0.882~0.988)。结论:CT定量参数(MIV、MEV)及NLR与COPD合并II型呼吸衰竭患者的肺功能具有相关性,且三者联合对预测患者预后具有较的效能。

关键词：慢性阻塞性肺疾病 Ⅱ型呼吸衰竭体层摄影术,X线计算机中性粒细胞/淋巴细胞比值肺功能预后

Simulation of the mixing process in FCIs with hydrodynamic fragmentation model

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Nuclear Science and Techniques 2007年第4期18卷 242-246页

作者： lin Qian cao Xuewu School of Nuclear Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

Fuel Coolant Interactions (FCIs) are important issues in nuclear reactor severe accident analysis. In FCIs, fragmentation model of molten droplets is a key factor to estimate degree of possible damage. In this paper, the mixing process in FCIs is studied by the simulation of MIXA experiment with hydrodynamic fragmentation model. The result shows that hydrodynamic fragmentation model underestimates the fragmentation rate of high temperature molten droplets under the condition of low Weber numbers. It is concluded that models based on thermal fragmentation mechanism should be adopted to analyze the FCI process and its consequence.

关键词：核反应堆燃料冷冻作用事故燃料熔化

依折麦布联合瑞舒伐他汀对脑梗死合并颈动脉粥样硬化斑块患者血清PTX3、sCD40L水平的影响

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药学前沿 2024年第9期28卷 57-64页

作者：张洁张海燕王玉曹薇曹琳邢台市中心医院健康体检中心河北邢台054000

目的探究依折麦布联合瑞舒伐他汀对脑梗死(CI)合并颈动脉粥样硬化(CAS)斑块患者血清正五聚蛋白3(PTX3)、可溶性CD40配体(sCD40L)水平的影响。方法回顾性分析2021年1月至2023年1月在邢台市中心医院神经内科诊治的CI合并CAS斑块患者资料,... 详细信息

目的探究依折麦布联合瑞舒伐他汀对脑梗死(CI)合并颈动脉粥样硬化(CAS)斑块患者血清正五聚蛋白3(PTX3)、可溶性CD40配体(sCD40L)水平的影响。方法回顾性分析2021年1月至2023年1月在邢台市中心医院神经内科诊治的CI合并CAS斑块患者资料,根据患者诊疗方案,将其分为联合组(依折麦布联合瑞舒伐他汀)和对照组(瑞舒伐他汀)。比较两组临床疗效、治疗前及治疗6个月后美国国立卫生研究院卒中量表(NIHSS)、日常生活活动能力(ADL)评分、动脉斑块积分、血脂指标[总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白(LDL-C)]、血清指标(PTX3、sCD40L水平)。结果研究纳入患者200例,对照组和联合组各100例。治疗后,联合组总有效率占比较高(P<0.05)。治疗后,两组NIHSS、ADL评分和动脉斑块积分、TC、TG、LDL-C、HDL-C水平、血清PTX3和sCD40L水平均较治疗前显著改善(P<0.05),且联合组改善程度优于对照组(P<0.05)。结论依折麦布联合瑞舒伐他汀可能对CI合并CAS患者具有一定价值,能改善神经功能,稳定并逆转CAS斑块,调节血脂水平和血清PTX3、sCD40L水平,提高生活质量。

关键词：依折麦布瑞舒伐他汀脑梗死颈动脉粥样硬化斑块正五聚蛋白3 可溶性CD40配体

Histone modifications in DNA damage response

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Science China(Life Sciences) 2016年第3期59卷 257-270页

作者： lin-lin cao Changchun Shen Wei-Guo Zhu Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) State Key Laboratory of Natural and BiomimeticDrugs Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function Department of Biochemistry and Molecular Biology Peking University Health Science Center Beijing 100191 China Peking University-Tsinghua University Joint Center for Life Sciences Beijing 100084 China Shenzhen University School of Medicine Shenzhen 518060 China Department of Clinical Laboratory Peking University People's Hospital Beijing 100044 China

DNA damage is a relatively common event in eukaryotic cell and may lead to genetic mutation and even cancer. DNA damage induces cellular responses that enable the cell either to repair the damaged DNA or cope with the damage in an appropriate way. Histone proteins are also the fundamental building blocks of eukaryotic chromatin besides DNA, and many types of post-translational modifications often occur on tails of histones. Although the function of these modifications has remained elusive, there is ever-growing studies suggest that histone modifications play vital roles in several chromatin-based processes, such as DNA damage response. In this review, we will discuss the main histone modifications, and their functions in DNA damage response.

关键词： DNA damage response histone modifications chromatin DNA repair

Effect of Cobalt Precursor on Microstructures and Visible Light Photoactivity of Doped TiO2 Powders

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Chinese Journal of Chemical Physics 2006年第5期19卷 463-468页

作者： Jing-ying Shi Wen-hua Leng Jiang-lin cao Jian-qing Zhang Chu-nan cao Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China Department of Chemistry Quanzhou Normal College Quanzhou 352000 China

In order to develop photoactive cobalt-doped TiO2 for the degradation of organic pollutants using visible light irradiation, the effects of cobalt precursor on TiO2 microstructure were investigated. Three cobaltprecursors, i.e. COCl2, Co（NO3）2 and COSO4 with two doping levels （nominally 1% and 10%）, and two annealing temperatures （400 and 800 ℃） were adopted to prepare tile doped titania through the sol-gel method. The powder samples were characterized with XRD, SEM, BET surface area analysis and UV-Vis absorption spectroscopy, and their photocatalytic activities were evaluated by the degradation of aniline under visible light irradiation. The results showed that the distribution of titania phases, particle size, morphology, surface area and the optical absorption of the catalysts were greatly dependent on the cobalt precursors. Samples prepared from Co（NO3）2, especially for those doped at 1% and calcined at 400 ℃, showed the highest photocatalytic activity towards the degradation of aniline, and the possible reasons are discussed briefly.

关键词： Cobalt precursor Doped titania Photocatalysis Visible light

基于网络药理学和分子对接探讨抗血小板药物治疗急性肺损伤的作用机制研究

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中国临床药理学杂志 2024年第6期40卷 914-917页

作者：牛镜向倩刘志艳王哲曹琳玉徐州医科大学药学院江苏徐州221004 北京大学第一医院药学部北京100034 北京大学第一医院临床药理研究所北京100034

目的基于网络药理学的策略来探究抗血小板药物治疗急性肺损伤的机制。方法通过SwissTargetPrediction平台预测抗血小板药物的靶点,用GeneCards和OMIM数据库获取急性肺损伤的相关靶点。通过STRING平台构建蛋白互作网络,用Cytoscape软件中... 详细信息

目的基于网络药理学的策略来探究抗血小板药物治疗急性肺损伤的机制。方法通过SwissTargetPrediction平台预测抗血小板药物的靶点,用GeneCards和OMIM数据库获取急性肺损伤的相关靶点。通过STRING平台构建蛋白互作网络,用Cytoscape软件中CytoHubba和MCODE插件,筛选出治疗急性肺损伤的核心靶点和高度连接的靶点簇,使用DAVID数据库对核心靶点进行基因本体(GO)、京都基因与基因百科全书(KEGG)基因富集分析,最后利用AutoDockTools软件进行分子对接验证。结果总共筛选出20个抗血小板药物治疗急性肺损伤的核心靶点,其中度值排名前3位的核心靶点是原癌基因酪氨酸蛋白激酶(SRC),磷脂酰肌醇3-激酶调节亚基1(PIK3R1)和信号转导与转录激活因子3(STAT3)。抗血小板药物可能通过调控表皮生长因子受体(ErbB)信号通路、程序性死亡受体-1(PD-1)/程序性死亡受体配体-1(PD-L1)信号通路、酪氨酸蛋白激酶信号转导与转录激活因子(JAK-STAT)来发挥治疗急性肺损伤的作用,分子对接结果进一步表明,抗血小板药物可以与核心靶点很好地结合。结论本研究从系统和整体的角度阐明了抗血小板药物治疗急性肺损伤的可能机制,为进一步研究抗血小板药物治疗急性肺损伤的药理机制提供新的思路。

关键词：抗血小板药物网络药理学急性肺损伤分子对接

互文性视角下的新时代中国外交修辞创新——以国家修辞形象构建为例

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海南开放大学学报 2024年第3期25卷 99-107,116页

作者：羊至刚段曹林海南师范大学文学院海南海口571158

中国特色社会主义新时代以来,我国外交话语在修辞上表现出了不同于前的明显创新特点。国家修辞形象作为外交话语的主要修辞成果之一,则较为集中地展现了新时代外交话语的修辞创新特点。以此为着眼点,分析以习近平外交演讲为代表的新时... 详细信息

中国特色社会主义新时代以来,我国外交话语在修辞上表现出了不同于前的明显创新特点。国家修辞形象作为外交话语的主要修辞成果之一,则较为集中地展现了新时代外交话语的修辞创新特点。以此为着眼点,分析以习近平外交演讲为代表的新时代外交话语,研究发现,新时代外交话语中主要构建了推动共同发展的和平友好大国、积极承担责任的最大发展中国家、具有独特魅力的东方文明古国等三种国家形象,国家形象构建背后的修辞逻辑则是互文性。

关键词：互文性新时代外交话语国家形象修辞创新

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