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Science China Chemistry 2025年

作者： Maolin Yang Yukun Liu Peng Yang yanhua zhao Xiaofeng Wu Leibniz-Institut für Katalyse e.V. Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences

A photochemically induced carbon monoxide-inclusive four-component carbonylation reaction has been delineated,facilitating the diacylation of styrenes with acyl azolium salts to synthesize valuable 1,4-diketone compounds with moderate to good *** process proceeds by generating acyl radicals from the Hantzsch esters and carbon monoxide,which subsequently add to the terminal position of ***,under light irradiation,the newly generated carbon radical can further react with activated acyl azolium salts to finish the desired 1,4-diketone products.

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Friction stir welding of high-strength aerospace aluminum alloy and application in rocket tank manufacturing

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Journal of Materials Science & Technology 2018年第1期34卷 73-91页

作者： Guoqing Wang yanhua zhao Yunfei Hao China Academy of Launch Vehicle Technology Beijing 100076 China Capital Aerospace Machinery Company Beijing 100076 China

Friction stir welding （FSW） has been widely adopted in aerospace industry for fabricating high-strength aluminum alloy structures, such as large volume fuel tanks, due to its exceptional advantages includ- ing low distortion, less defects and high mechanical properties of the joint. This article systematically reviews the key technical issues in producing large capacity aluminum alloy fuel tanks by using FSW, including tool design. FSW process optimization, nondestructive testing （NDT） techniques and defect repairing techniques, etc. To fulfill the requirements of Chinese aerospace industry, constant-force FSW, retractable tool FSW, lock joint FSW, on-line NDT and solid-state equal-strength FSW techniques, as well as a complete set of aerospace aluminum FSW equipment, have been successfully developed. All these techniques have been engineered and validated in rocket tanks, which enormously improved the fabrication ability of Chinese aerospace industry.

关键词： Fuel tank High-strength aluminum alloy Friction stir welding Application

Novel method of improving the alignment accuracy of SINS on revolving mounting base

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1052-1057页

作者： Qian Weixing Liu Jianye zhao Wei Zhu yanhua Navigation Research Center Nanjing Univ. of Aeronautics ~z Astronautics Nanjing 210016 P. R. China

In the process of initial alignment for a strapdown inertial navigation system （SINS） on a stationary base, the east gyro drift rate is an important factor affecting the alignment accuracy of the azimuth misalignment angle. When the Kalman filtering algorithm is adopted in initial alignment, it yields a constant error in the estimation of the azimuth misalignment angle because the east gyro drift rate cannot be estimated. To improve the alignment accuracy, a novel alignment method on revolving mounting base is proposed. The Kalman filtering algorithm of extending the measured values is studied. The theory of spectral condition number is utilized to analyze the degrees of observability of states. Simulation results show that the estimation accuracy of the azimuth misalignment angle is greatly improved through revolving mounting base, and the proposed method is efficient in initial alignment for a medium accurate SINS.

关键词： inertial navigation initial alignment observability analysis Kalman filter spectral condition number.

Nicotine-induced upregulation of antioxidant protein Prx 1 in oral squamous cell carcinoma

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Chinese Science Bulletin 2013年第16期58卷 1912-1918页

作者： zhao yanhua ZHANG Min YAN Fei CASTO Bruce C TANG XiaoFei Division of Oral Pathology Beijing Institute of Dental Research School of Stomatology Capital Medical University Division of Medical Oncology Department of Internal Medicine Ohio State University College of Medicine and Comprehensive Cancer Center Division of Environmental Health Sciences Ohio State University College of Public Health

Nicotine is a source of exogenous oxidative stress, which is associated with the pathogenesis of numerous diseases including oral squamous cell carcinoma (OSCC), whereas an antioxidant protein, peroxiredoxin 1 (Prx 1), plays an important role in the modulation of this condition. This study was to investigate the association between Prx 1 and tobacco-induced oxidative stress. The expression of Prx 1 and GST in OSCC Tca8113 cells, which were pre-treated with nicotine, was determined. In the present study, MTT assay, reactive oxygen species (ROS) assay, RT-PCR and Western blot analyses, respectively, were conducted to assess cell viability, ROS level, and expression level of Prx 1 and GST in nicotine-treated Tca8113 cells. Nuclear factor kappa B (NF- B) expression was detected by immuno-fluorescence. Our results showed the growth of Tca8113 cells was increased in a dose-dependent manner when cells were treated with nicotine at concentrations from 0.1 to 10 mol/L, but the proliferation of the cells decreased at 100 mol/L. ROS levels increased in all groups treated with nicotine at concentrations of 0.1, 1, 10, or 100 mol/L for 24h. Prx 1 and GST mRNA and protein expression were up-regulated in cells treated with nicotine for the same time at different concentrations or at the same concentration for different times (P<0.05). NF-B was translocated from cytoplasm to nucleus, the expression of NF- B was increased in nucleus. These results suggest that up-regulation of Prx1 expression appears to be associated with tobacco-induced oxidative stress, which may play an important role in the pathogenesis of OSCC.

关键词：鳞状细胞癌蛋白表达抗氧化剂尼古丁口腔诱导氧化应激 RT-PCR

Super-resolution microscopy of live cells using single molecule localization

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Chinese Science Bulletin 2013年第36期58卷 4519-4527页

作者： ZHANG YongDeng CHANG Hao GU LuSheng zhao yanhua XU Tao JI Wei School of Life Science and Technology Huazhong University of Science and Technology School of Life Science University of Science and Technology of China Institute of Biophysics Chinese Academy of Sciences

The resolution of conventional light microscopy is insufficient for subcelluar *** invention of various super-resolution imaging techniques breaks the diffraction barrier and pushes the resolution limit towards the nanometer ***,we focus on a category of super-resolution microscopy that relies on the stochastic activation and precise localization of single molecules.A diversity of fluorescent probes with different characteristics has been developed to achieve super-resolution *** addition,with the implementation of robust localization algorithms,this family of approaches has been expanded to multi-color,three-dimensional and live cell imaging,which provides a promising prospect in biological research.

关键词：超高分辨率光学显微镜活细胞成像分子定位成像技术超分辨率分辨率极限纳米尺度

克氏原螯虾(Procambarus clarkii)形态性状与净肉重及出肉率的相关性

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江苏农业学报 2025年第1期41卷 126-133页

作者：孙梦玲薛晖徐宇赵彦华李佳佳姜虎成许志强农业农村部淡水虾蟹遗传育种与养殖重点实验室江苏南京210017 江苏省淡水水产研究所江苏南京210017

为探究克氏原螯虾形态性状与净肉重和出肉率之间的关系,本研究以194尾成年克氏原螯虾为试验材料,测量克氏原螯虾12个形态性状,包括全长、体长、螯肢长、头胸甲长、头胸甲宽、头胸甲高、第一腹节长、第一腹节宽、第一腹节高、腹甲长、尾... 详细信息

为探究克氏原螯虾形态性状与净肉重和出肉率之间的关系,本研究以194尾成年克氏原螯虾为试验材料,测量克氏原螯虾12个形态性状,包括全长、体长、螯肢长、头胸甲长、头胸甲宽、头胸甲高、第一腹节长、第一腹节宽、第一腹节高、腹甲长、尾扇长和尾扇宽,并进行相关性分析、多元回归分析和通径分析。相关性分析结果表明,与雌虾出肉率呈极显著相关的性状有腹甲长与第一腹节长(P<0.01);与雄虾出肉率呈极显著相关的性状有螯肢长、头胸甲宽及腹甲长(P<0.01),呈显著相关的性状有体长、头胸甲高(P<0.05)。通径分析结果表明,螯肢长对克氏原螯虾雌虾和雄虾出肉率具有负向直接效应;腹甲长和第一腹节长对雌虾的净肉重和出肉率具有正向直接效应,头胸甲高和头胸甲长对雄虾的净肉重和出肉率具有正向直接效应。本研究结果可为克氏原螯虾育种提供理论依据。

关键词：克氏原螯虾形态性状多元回归分析通径分析净肉重出肉率

河北省城乡居家社区养老服务资源配置与优化路径

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衡水学院学报 2025年第1期27卷 71-78页

作者：赵艳华王光星吴元元董莉河北地质大学法政学院河北石家庄050000 河北地质大学区域制度研究中心河北石家庄050000 河北省卫生健康委员会综合监督服务中心河北石家庄050051

随着人口老龄化的加剧和计划生育政策的影响,单纯依靠家庭养老已经不能满足社会需求,居家社区养老成了主要发展方向。通过分析河北省城乡居家社区养老服务资源供给现状,发现养老服务资源配置在财政补贴政策、城乡养老服务资源配置、养... 详细信息

随着人口老龄化的加剧和计划生育政策的影响,单纯依靠家庭养老已经不能满足社会需求,居家社区养老成了主要发展方向。通过分析河北省城乡居家社区养老服务资源供给现状,发现养老服务资源配置在财政补贴政策、城乡养老服务资源配置、养老机构人力资源和服务等方面存在许多问题,并受居家养老与机构养老主辅关系不清、财政补贴力度失衡、硬件设施不足以及养老服务人力资源短缺等因素的制约。为实现养老服务资源的优化配置,应建立养老服务事业与产业协同发展机制,完善财政补贴政策体系,建立“夫孝”金和长期护理保险制度,规范和提升养老机构服务水平。

关键词：居家社区养老养老服务资源配置河北省

Protective benefits of HDPE board sand fences in an environment with variable wind directions on Gobi surfaces:wind tunnel study

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Journal of Mountain Science 2024年第10期21卷 3353-3367页

作者： ZHANG Kai TIAN Jianjin LIU Benli zhao yanhua ZHANG Hailong WANG Zhenghui DENG Yuhui College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The Golmud-Korla Railway in the Gobi area faces operational challenges due to sand hazards,caused by strong and variable *** study addresses these challenges by conducting wind tunnel tests to evaluate the protective benefits of High Density Polyethylene(HDPE)board sand fences,focusing on their orientation relative to various wind directions(referred to as'wind angle').This study found that the size of the low-velocity zone on the leeward side of the sand fences(LSF)expanded with an increase in the wind angle(WA).At 1H(the height of the sand fence)and 2H positions on the LSF,the wind speed profiles(WSP)exhibited a segmented logarithmic growth,constrained by Z=H at varying *** efficacy of the sand fence in obstructing airflow escalated as WA *** size of the WA has a significant impact on the protective efficiency of HDPE board sand ***,compared to typical sandy surfaces,the rate of sand transport across the Gobi surface diminishes more slowly with height,attributed to the gravel's rebound *** phenomenon allows some sand particles to bypass the fences,rendering them less effective at blocking wind and trapping sand than in sandy *** paper offers scientific evidence supporting the practical use and enhancement of HDPE board sand fences in varied wind conditions.

关键词： Variable wind directions Blown sand control Wind tunnel tests HDPE board sand fences

Laser Additive Manufacturing of 316L Stainless Steel Thin-wall Ring Parts

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Fluid Dynamics & Materials Processing 2023年第2期19卷 451-470页

作者： yanhua zhao Wenhao Tian Jianhua Liu Dongqing Qian Wei Meng Jiaming Wang School of Mechanical and Electrical Engineering Shandong Jianzhu UniversityJinan250101China Hangzhou Optimax Tech Co. Ltd.HangzhouZhejiang310052China Shandong Research Institute of Industrial Technology Additive Manufacturing Collaborative Innovation Center Jinan250101China

The process parameters of laser additive manufacturing have an important influence on the forming quality of the produced items or *** the present work,a finite element model for simulating transient heat transfer in such processes has been implemented using the ANSYS software,and the temperature and stress distributions related to 316L stainless steel thin-walled ring parts have been simulated and *** effect of the laser power,scanning speed,and scanning mode on temperature distribution,molten pool structure,deformation,and stress field has been *** simulation results show that the peak temperature,weld pool size,deformation,and residual stress increase with an increase in laser power and a decrease in the scanning *** scanning mode has no obvious effect on temperature distribution,deformation,and residual *** addition,a forming experiment was carried *** experimental results show that the samples prepared by laser power P=800 W,V=6 mm/s,and the normal scanning method display good quality,whereas the samples prepared under other parameters have obvious *** experimental findings are consistent with the simulation results.

关键词： Laser additive manufacturing 316L stainless steel temperature field stress field

Enhanced Fatigue Properties of 2219 Al Alloy Joints via Bobbin Tool Friction Stir Welding

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Acta Metallurgica Sinica(English Letters) 2023年第4期36卷 586-596页

作者： Zhenlin Wang Beibei Wang Zhen Zhang Peng Xue Yunfei Hao yanhua zhao Dingrui Ni Guoqing Wang Zongyi Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China China Academy of Launch Vehicle Technology Beijing 100076China Capital Aerospace Machinery Company Beijing 100076China

In the present study,2219-T87 Al alloy plates,4 mm in thickness,were subjected to bobbin tool friction stir welding(BTFSW)under relatively high welding speeds of 200 and 400 mm/min,with the aim to analyze the effect of welding speeds on fatigue properties of the *** results showed that the tension–tension high-cycle fatigue performance of the BT-FSW joints at room temperature was significantly enhanced compared to that of other joints of 2xxx series Al alloys *** at a high welding speed of 400 mm/min,the fatigue strength of the joint reached 78%of the base material together with a high tensile strength of 311 *** was found that the joint line remnants had no effects on the fatigue properties of the BT-FSW joints due to the elimination of root flaws under the action of the lower *** of the samples with the welding speed of 200 mm/min failed at the thermo-mechanical zone(TMAZ)during fatigue tests,attributable to the coarsened grains and precipitates,but all of the samples with high welding speed of 400 mm/min randomly failed at the nugget zone due to the improved hardness value in the TMAZ.

关键词： 2219 Al alloys Bobbin tool friction stir welding Microstructure Fatigue properties