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基于主成分和体外抗氧化活性的酒萸肉的蒸制研究

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时珍国医国药 2024年第3期35卷 644-647页

作者：杨菁蕾代萌王肇扬乔博灵西北大学教育部西部资源生物与生物技术重点实验室陕西西安710069 陕西省中药创新药物工程技术研究中心陕西西安710069

目的考察酒萸肉炮制中黄酒和蒸制对主成分和抗氧化活性的影响。方法制备蒸制时间为0.5,1,2,3,5和7 h的清蒸和酒蒸山萸肉样品,采用高效液相色谱法,测定没食子酸、5-羟甲基糠醛、莫诺苷、马钱苷、山茱萸新苷I含量;应用主成分分析法,明确... 详细信息

目的考察酒萸肉炮制中黄酒和蒸制对主成分和抗氧化活性的影响。方法制备蒸制时间为0.5,1,2,3,5和7 h的清蒸和酒蒸山萸肉样品,采用高效液相色谱法,测定没食子酸、5-羟甲基糠醛、莫诺苷、马钱苷、山茱萸新苷I含量;应用主成分分析法,明确清蒸和酒蒸的差异;利用DPPH法测定抗氧化活性。结果随蒸制时间的增加,新生成分5-羟甲基糠醛含量明显增加,清蒸高于酒蒸;没食子酸含量明显增加,酒蒸高于清蒸;莫诺苷、马钱苷、山茱萸新苷I含量,在清蒸样品中明显下降,在酒蒸样品中先上升,5 h后开始下降;抗氧化活性,与生萸肉相比,清蒸样品明显下降,酒蒸样品明显上升。结论黄酒在酒萸肉的炮制中具有重要作用,可以促进没食子酸的生成,减缓蒸制导致的主成分含量的下降,增强抗氧化活性,调控5-羟甲基糠醛的生成。

关键词：山萸肉清蒸酒蒸主成分抗氧化活性 5-羟甲基糠醛

MXenes/多糖复合材料在水处理方面的研究进展

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应用化工 2024年第5期53卷 1186-1190页

作者：赖欣雨王朝阳邓立高广西大学轻工与食品工程学院广西南宁530004

总结了近五年来MXenes/多糖复合材料在水处理方面的研究进展。简要介绍了MXene的制备方法。接着根据形态不同,对水处理中的MXenes/多糖复合材料进行了分类,介绍了其制备工艺。讨论了MXenes/多糖复合材料在水体净化、水油分离和海水淡化... 详细信息

总结了近五年来MXenes/多糖复合材料在水处理方面的研究进展。简要介绍了MXene的制备方法。接着根据形态不同,对水处理中的MXenes/多糖复合材料进行了分类,介绍了其制备工艺。讨论了MXenes/多糖复合材料在水体净化、水油分离和海水淡化三方面的应用研究情况。对MXenes/多糖复合材料的发展前景和挑战进行了展望。研究对进一步设计高效水处理MXenes/多糖复合材料具有重要参考价值。

关键词： MXenes 多糖水处理水净化油水分离海水淡化

Practical method and application study for predicting cyclic accumulative deformations of the saturated soft clay

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Journal of Mountain Science 2017年第11期14卷 2348-2358页

作者： HE Lin-lin wang Yuan-zhan LI Shu-zhao wang zhao-yang Key Laboratory of Hydraulic and Waterway Engineering of Ministry of Education Key Laboratory of regulation technology for inland waterway in transportation industry Chongqing Jiaotong University State Key Laboratory for Simulation & Safety of Hydraulic Engineering Tianjin Key Laboratory of Harbor & Ocean Engineering Tianjin University CNOOC Research Institute

The distribution of saturated soft clay is greatly wide in China. The current main measures adopted to deal with soft soil foundations may lead to environmental pollution, even some engineering accidents may happen on soft soil foundations. In order to solve engineering problems of saturated soft soil foundations well, researches of mechanical properties of them are necessary. One of the most important mechanical characteristics of saturated soft clay is its cyclic accumulative deformation under cyclic loadings. For saturated soft clay, the cyclic accumulative deformation is similar to the creep behavior under static loadings. Therefore, the cyclic accumulative deformation is equivalent to the creep, the number of loading cycles is seen as the time, and this study develops a practical method for predicting the cyclic accumulative deformation of saturated soft clay with the creep theory. The method is a pseudostatic elasto-plastic finite element method implemented by ABAQUS software. A fitted equation between cyclic accumulative strain and number of loading cycles and the empirical relationship of parameters of fitted equation were established with aseries of cyclic triaxial compression tests. Then with this empirical relationship of parameters, the method developed by this study was employed to predict the cyclic accumulative deformation under cyclic triaxial tension tests. Predicted results were in good agreement with test results, and the effectiveness of this method was thus validated for different stress states. The method was then applied in analyzing the cyclic accumulative deformation for soft soil foundation of a pile-supported wharf structure.

关键词： Saturated soft clay Finite elementmethod Soil tests Cyclic accumulativedeformation Creep theory

Density distribution in a heavy-medium cyclone

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Mining Science and Technology 2011年第2期21卷 175-179页

作者： wang Yuling zhao Yuemin yang Jianguo School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou 221008 China

Heavy-medium cyclones are widely used to upgrade run-of-mine *** the understanding of flow in a cyclone containing a dense medium is still *** introducing turbulent diffusion into calculations of centrifugal settling a theoretical distribution function giving the density field can be *** analysis of the density field in every part of a cylindrical cyclone suggests an optimum design that has exhibited good separation effectiveness and anti-wear performance when in commercial operation.

关键词： Heavy-medium cyclone Density field Density flow model Optimization

Asymmetric Synthesis of (R)-and (S)-Moprolol

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Chemical Research in Chinese Universities 2008年第6期24卷 747-751页

作者： wang zhao-yang wang Yan SUN Li-wen ZHU Jin-tao Department of Chemistry Zhejiang Sci-Teeh University Hangzhou 310018 P. R. China Institute of Materia Mediea Zhejiang Aeademy of Medical Science Hangzhou 310013 P. R. China

A simple and effective procedure for the enantioselective synthesis of （R）- and （S）-moprolol was described. The key step was the asymmetric synthesis of enantiopure （R）- and （S）-guaifenesin, which were synthesized from enantioenriched （R）-3-chloro-l,2-propanediol and （S）-epichlorohydrin via kinetics of hydrolysis resolution of racemic epichlorohydrin by chiral Salen-Co^Ⅲ complex. The e.e. values of both the optical compounds were above 98%, and the chemical structures of the target compounds were confirmed by ^1H NMR, ^13C NMR, IR, and MS.

关键词： (R)- and (S)-Moprolol (R)- and (S)-Guaifenesin Asymmetric synthesis

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我国药品集中带量采购政策扩散分析

中国卫生政策研究 2024年第9期17卷 76-82页

作者：高一博王兆旸吕博赵婧萱谢佳鑫薛咏茜高雨润孟开首都医科大学公共卫生学院北京100069 首都医科大学附属北京天坛医院北京100070

目的:开展我国近年来药品集中带量采购相关的政策扩散分析,为我国药品集中带量采购政策的制定提供参考依据。方法:通过中央及各省级政府官网、卫生健康委员会官网、医疗保障局官网等途径,检索2009年1月1日—2023年12月31日涉及药品集中... 详细信息

目的:开展我国近年来药品集中带量采购相关的政策扩散分析,为我国药品集中带量采购政策的制定提供参考依据。方法:通过中央及各省级政府官网、卫生健康委员会官网、医疗保障局官网等途径,检索2009年1月1日—2023年12月31日涉及药品集中带量采购的政策文件。基于政策扩散理论,采用参照网络分析法分析政策扩散的强度、广度和速度,使用政策关键词时序分析法分析政策的扩散方向。结果:在药品集中带量采购政策发展的两个阶段中,医保治理阶段的政策出台量达到高峰;扩散强度、广度最高的前十项政策均为中央政策,并且多以通知和意见类为主,此外,较新颁布的政策,扩散速度更快;扩散方向上,自上而下和平行扩散两种扩散趋势较为明显。结论:我国药品集中带量采购政策扩散以中央政策为重点,扩散速度逐年上升,建议加强中央与地方的政策协同,建立全国统一的药品集中带量采购信息平台,并优化各级政府之间的学习和竞争机制,发挥“政策试验”的优势。

关键词：药品集中带量采购政策扩散政策网络分析政策时序分析

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商用车通过噪声优化研究

内燃机与配件 2024年第11期 19-21页

作者：梁帅金明吴萍王朝阳长城汽车股份有限公司河北保定071000

某纯电重卡根据GB 1495-2002《汽车加速行驶车外噪声限值及测量方法》进行测试时,发现动力模式(P模式)下,50km/h进线时,车外噪声测试结果为84.9dB(A),不满足限值(≤84 dB(A)),根据主观感受结果和频谱图滤波回放,确认问题发生频率在2500H... 详细信息

某纯电重卡根据GB 1495-2002《汽车加速行驶车外噪声限值及测量方法》进行测试时,发现动力模式(P模式)下,50km/h进线时,车外噪声测试结果为84.9dB(A),不满足限值(≤84 dB(A)),根据主观感受结果和频谱图滤波回放,确认问题发生频率在2500Hz左右,跟踪电机转速发现电机的2.2阶能量贡献明显,并结合电机参数和内部传动结构特性,计算对应阶次零部件为轮边减速器,通过吸音棉包裹、更换新样件等方案验证,最终发现轮边减速器齿轮精度和轮边减速器啮合激励与端盖模态耦合共振,导致噪声增大,通过提高端盖模态和提高轮边减速器齿轮精度,问题得到优化。

关键词：商用车通过噪声轮边减速器阶次分析模态优化

Differences and similarities in radial growth of Betula species to climate change

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Journal of Forestry Research 2024年第2期35卷 176-187页

作者： Di Liu yang An zhao Li Zhihui wang Yinghui zhao Xiaochun wang Center for Ecological Research Key Laboratory of Sustainable Forest Ecosystem ManagementMinistry of EducationCollege of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Changan Park in Shijiazhuang Shijiazhuang 050000People’s Republic of China Shijiazhuang Landscape Greening Engineering Project Construction Center Shijiazhuang 050000People’s Republic of China Heilongjiang Institute of Meteorological Science Harbin 150030People’s Republic of China School of Life Qufu Normal UniversityQufu 273100People’s Republic of China

Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)***,the specific ways in which their growth is affected by warm temperatures and drought remain *** address this issue,60 and 62 tree-ring cores of *** and *** were collected in Yichun,*** dendrochronological methods,the response and adaptation of these species to climate change were examined.A“hysteresis effect”was found in the rings of both species,linked to May–September moisture conditions of the previous *** growth of *** was positively correlated with the standardized precipitation-evapotranspiration index(SPEI),the precipitation from September to October of the previous year,and the relative humidity in October of the previous *** of *** is primarily restricted by moisture conditions from September to *** contrast,*** growth is mainly limited by minimum temperatures in May–June of both the previous and current *** droughts,*** had a faster recovery rate compared to *** the context of rising temperatures since 1980,the correlation between *** growth and monthly SPEI became positive and strengthened over time,while the growth of *** showed no conspicuous *** findings suggest that the growth of *** is already affected by warming temperatures,whereas *** may become limited if warming continues or *** change could disrupt the succession of these species,possibly accelerating the succession of pioneer *** results of this research are of great significance for understanding how the growth changes of birch species under warming and drying conditions,and contribute to understanding the structural adaptation of mixed broadleaved-Korean pine(Pinus koraiensis)forests under climate change.

关键词： Tree rings Betula platyphylla Betula costata Climate response Moving correlation Extreme drought

Effects of Bionic Leading Edge on the Aerodynamic Performance of a Compressor Cascade at a Low Reynolds Number

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Journal of Thermal Science 2024年第4期33卷 1272-1285页

作者： XU Huafeng zhao Shengfeng wang Mingyang yang Chengwu Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing100049China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing100190China

To achieve high-performance compressor cascades at low Reynolds number(Re),it is important to organize the boundary layer transition and separation processes efficiently and *** this study,the airfoil is focused on at a 5%blade height at the root of the orthogonal blade in the downflow passage of the high-load booster *** bionics modeling design is carried out for the leading edge of the original blade cascade;the response characteristics of laminar transition and separation to blades with different leading edge shapes at low Reynolds numbers are studied by using large eddy simulations combined with Omega vortex *** findings of this study demonstrate that bionic leading edge modeling can significantly improve the aerodynamic performance of blades at low Reynolds *** blades effectively suppress the formation of separation bubbles at low Reynolds numbers and weaken or even eliminate large-scale flow separation at the trailing *** addition,the blades can weaken the vortex intensity on the blade surface,reduce the areas of high-velocity fluctuations,and minimize aerodynamic losses caused by turbulence *** results should serve as a valuable reference for the aerodynamic design and flow control of the high-load booster stage blade at low Re.

关键词： low Reynolds number booster stage bionic leading edge large eddy simulation