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Heat treatment bimetallic PdAu nanocatalyst for oxygen reduction reaction

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Journal of Energy Chemistry 2020年第1期29卷 217-223,I0008页

作者： Qingyun Hu Wei Zhan yifei guo Laiming Luo Ronghua Zhang Di Chen Xinwen Zhou College of Biological and Pharmaceutical Science China Three Gorges University

Pd-based nanocatalyst is a potential oxygen reduction oxidation(ORR)catalyst because of its high activity in alkaline medium and low cost.In this work,bimetallic Pd Au nanocatalysts are prepared by one-pot hydrothermal method using triblock pluronic copolymers,poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)(PEO19-PPO69-PEO19)(P123)as reducer and stabilizer,and heat-treatment method is applied to regulate catalyst structure and improve catalyst activity.The results show that the heat treatment can agglomerate the catalyst to a certain extent,but effectively improve the crystallinity and alloying degree of the catalyst.The ORR performance of the Pd Au nanocatalysts obtained under different heat treatment conditions is systematically investigated.Compared with commercial Pd black and Pd Au catalyst before heat treatment,the ORR performance of Au Pd nanocatalyst obtained after heat treatment for one hour at 500℃ has been enhanced.The Pd Au nanocatalysts after heat treatment also display enhanced anti-methanol toxicity ability in acidic medium.

关键词： PdAu catalysts Nanochain Heat treatment Oxygen reduction reaction Anti-methanol oxidation

贵州少数民族刺绣中钉线绣工艺的运用及其比较

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毛纺科技 2024年第3期52卷 56-62页

作者：马晨曲陈洁郭易非杜雨翎李林臻东华大学服装与艺术设计学院上海200051 上海视觉艺术学院时尚设计学院上海201620

为了将贵州各民族中钉线绣工艺更广泛的运用到刺绣作品中,对比分析最具代表性的水族马尾绣、舟溪苗族蚕锦绣、革一苗族梗边打籽绣、织金苗族绞线绣以及黔东南侗族盘筋绣,研究5种刺绣在钉线绣综线内芯材质、综线丝线的色彩、使用位置、... 详细信息

为了将贵州各民族中钉线绣工艺更广泛的运用到刺绣作品中,对比分析最具代表性的水族马尾绣、舟溪苗族蚕锦绣、革一苗族梗边打籽绣、织金苗族绞线绣以及黔东南侗族盘筋绣,研究5种刺绣在钉线绣综线内芯材质、综线丝线的色彩、使用位置、刺绣中所结合使用的其他刺绣工艺以及在服饰中装饰的位置方面的特色,从图案审美角度鉴赏5种刺绣所形成的刺绣图案,分析不同刺绣在综线质感、造型风格、色彩3个方面的表现,总结出不同民族不同刺绣中独特的审美偏好,为研究刺绣艺术以及以刺绣艺术现代设计创新提供新的视角。

关键词：钉线绣刺绣水族苗族侗族

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磁控触变流体的3D打印工艺研究

材料科学与工艺 2024年第2期32卷 55-65页

作者：张圣杰李振坤耿子健郭乙飞宋仲儒董珈皓李占贤华北理工大学机械工程学院河北唐山063210 北京交通大学机械与电子控制工程学院北京100044 河北省工业机器人产业技术研究院河北唐山063210

针对现有磁控智能流体无法应用于3D打印的问题,本文制备了一种在磁场调控下能够实现溶胶-凝胶可逆转变的新型磁控触变流体,并对其打印工艺进行了研究。采用全系统损耗润滑油、有机膨润土和Fe_(3)O_(4)颗粒制备了不同配比的打印样品,搭... 详细信息

针对现有磁控智能流体无法应用于3D打印的问题,本文制备了一种在磁场调控下能够实现溶胶-凝胶可逆转变的新型磁控触变流体,并对其打印工艺进行了研究。采用全系统损耗润滑油、有机膨润土和Fe_(3)O_(4)颗粒制备了不同配比的打印样品,搭建了直写式3D打印实验平台,研究其可打印性。流变学实验表明:磁控触变流体有机膨润土含量越高,触变性越强,剪切变稀越明显;磁场强度越强,屈服应力越高,储存模量越高。3种挤出方式下的打印实验结果表明,采用匀料恢复挤出方式打印的结构具备最高分辨率和最大高度。磁控触变流体在根据其流变特性设计的挤出装置下具有良好可打印性,为该材料应用于柔性传感、软体机器人个性化复杂结构设计与驱动、微流控检测等领域奠定了基础。

关键词：磁场调控磁控触变流体 3D打印打印工艺流变性能

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SEC-ICPMS AND ESI-MS/MS FOR EVALUATION OF THE BIOCHEMICAL RESPOND OF PLANTS TO HEAVY METAL STRESS

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SEC-ICPMS AND ESI-MS/MS FOR EVALUATION OF THE BIOCHEMICAL RE...

输尿管镜引导下经尿道组织钳取出膀胱大体积异物一例报告

第十二届北京分析测试学术报告会暨展览会(BCEIA2...

作者： Liqin Chen yifei guo Limin Yang Qiuquan Wang Department of Chemistry & the MOE Key Laboratory of Analytical Sciences College of Chemistry and Chemical Engineering Xiamen University

Size-exclusion chromatography(SEC)coupled with ICP-MS and ESI-MS/MS have been demonstrated as powerful and promising techniques for screening and identifying the in-vivo metallopeptides,with accurate isotopic distribution assignment,in metal toxicological studies.In this presentation,I will talk about the identification of in-vivo Cd-PC and Hg-PC complexes in Brassica chinensis

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中华腔镜泌尿外科杂志(电子版) 2024年第3期18卷 294-295页

作者：许娟郭逸飞张玥睢晓静张兵滑县人民医院泌尿外科

本文报道一例因“耻骨上疼痛、排尿困难伴血尿1 h”急诊入院的女性患者，影像学检查提示膀胱内异物，大小11.7 cm×1.8 cm，因异物体积较大，遂采用输尿管镜引导经尿道组织钳取出，未损伤尿道。此方法为膀胱异物取出提供了新的思路。

关键词：膀胱内异物组织钳输尿管镜

Synergistic defensive mechanism of phytochelatins and antioxidative enzymes in Brassica chinensis L. against Cd stress

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Chinese Science Bulletin 2008年第10期53卷 1503-1511页

作者： CHEN LiQin guo yifei YANG LiMin WANG QiuQuan Department of Chemistry and the MOE Key Laboratory of Modern Analytical Science College of Chemistry and Chemical Engi- neering Xiamen University Xiamen 361005 China State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

Brassica chinensis L. was chosen and exposed to different concentrations of Cd exposure to evaluate its Cd-accumulating capacity and its potential cellular defensive mechanisms. Cd accumulation in the shoots and roots of B. chinensis was up to 1348.3±461.8 and 3761.0±795.0 mg per killogram of dry weight, respectively, under 200 μmol/L of Cd exposure. Increasing Cd accumulation in the plant was accompanied by rapid accumulation of phytochelatins (PCs), and the sequestration of Cd by PCs provided a primary cellular mechanism for Cd detoxification and tolerance of B. chinensis. Furthermore, malondialdehyde formation, hydrogen peroxide content and antioxidative enzyme activities such as superoxide dismutase, catalase, guaiacol peroxidase and ascorbate peroxidase were observed in the shoots of Cd-stressed B. chinensis. Increasing enzyme activities in response to concentrations of 5 to 50 μmol/L Cd showed an efficient defense against oxidative stress, suggesting that the antioxidative system was a secondary defensive mechanism. These resulted in reduced free Cd damage and enhanced Cd accumulation and tolerance. Glutathione plays a pivotal role in these two detoxification pathways. In general, these results suggested that PCs and the antioxidative system are synergistic in combatting Cd-induced oxidative stress and that they play important roles in Cd detoxification of B. chinensis, and also give a deep understanding of the natural defensive mechanisms in plants under heavy metal stress.

关键词：镉芸苔植物化学酶类

金水葶苓汤对肺癌移植瘤恶性胸腔积液模型小鼠的治疗作用及机制研究

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中医药导报 2024年第1期30卷 26-30页

作者：赵林涛缑娇王松海杨宝钢郭弈飞宋延平杨晨光陕西省中医药研究院陕西西安710003 陕西省中医医院陕西西安710003 陕西中医药大学陕西咸阳712046

目的:通过复制Lewis肺癌移植瘤胸腔积液小鼠模型,考察金水葶苓汤对模型小鼠胸腔积液的抑制作用。方法:通过胸腔注射Lewis细胞复制C57小鼠胸腔积液肺癌模型,观察金水葶苓汤及金水葶苓汤协同顺铂注射液对模型小鼠胸腔积液体积、胸壁转移... 详细信息

目的:通过复制Lewis肺癌移植瘤胸腔积液小鼠模型,考察金水葶苓汤对模型小鼠胸腔积液的抑制作用。方法:通过胸腔注射Lewis细胞复制C57小鼠胸腔积液肺癌模型,观察金水葶苓汤及金水葶苓汤协同顺铂注射液对模型小鼠胸腔积液体积、胸壁转移瘤数量和转移瘤质量、生存时间的影响;采用Western blotting法检测壁层胸膜AQP1和胸腔积液中VEGF蛋白表达的水平,评价金水葶苓汤对肺癌移植瘤胸腔积液小鼠的治疗作用和机制。结果:与模型组比较,各给药组小鼠体质量增长明显升高,胸腔积液体积、胸壁转移瘤数量、转移瘤质量明显降低,小鼠胸腔积液中VEGF及胸膜中AQP1蛋白表达明显低于模型组,差异均有统计学意义(P<0.05或P<0.01),且金水葶苓汤+顺铂组比单用金水葶苓汤或顺铂注射液效果更好,差异有统计学意义(P<0.05)。结论:金水葶苓汤可以抑制恶性胸腔积液模型小鼠胸腔积液生成,改善小鼠体质量,延长小鼠生存时间,降低胸壁肿瘤转移数量和抑制肿瘤生长,降低胸腔积液中VEGF及胸膜中AQP1蛋白表达水平,且金水葶苓汤协同顺铂注射液优于金水葶苓汤或顺铂注射液单用效果。

关键词：恶性胸腔积液肺癌金水葶苓汤顺铂注射液血小板内皮生长因子水道蛋白1 小鼠

Dynamic tracking of exsolved PdPt alloy/perovskite catalyst for efficient lean methane oxidation

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Chinese Chemical Letters 2024年第4期35卷 170-175页

作者： Yanling Yang Zhenfa Ding Huimin Wang Jianhui Li Yanping Zheng Hongquan guo Li Zhang Bing Yang Qingqing Gu Haifeng Xiong yifei Sun College of Energy Xiamen UniversityXiamen 361005China School of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808China Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361102China

Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts was still frequently observed. Herein, we reinforced the extruded Pd nanoparticles with quantitive Pt to assemble the evenly distributed Pd Pt nanoalloy onto ferrite perovskite(Pd Pt-LCF) matrix with strengthened robustness of metal/oxide support interface. We further co-achieved the enhanced performance, anti-overoxidation as well as resistance of vapor-poisoning in durability measurement. The operando X-ray photoelectron spectroscopy(O-XPS) combined with various morphology characterizations confirms that the accumulation of surface deep-oxidation species of Pd^(4+) is the culprit for fast activity loss in exsolved Pd system, especially at high temperature of 400 ℃. Conversely, it could be completely suppressed by in-situ alloying Pd with equal amount of Pt, which helps maintain the metastable Pd^(2+)/Pd shell and metallic solid-solution core structure. The density function theory(DFT) calculations further buttress that the dissociation of C–H was facilitated on alloy/perovskite interface which is, on the contrary, resistant toward O–H bond cleavage, as compared to Pd/perovskite. Our work suggests that the modification of exsolved metal/oxide catalytic interface could further enrich the toolkit of heterogeneous catalyst design.

关键词： Exsolution PdPt alloy Operando characterization Methane conversion Deep-oxidation

The DFT Studies to Mechanisms of the Cationic Cobalt(Ⅲ) Catalyzed Regioselective Intermolecular Cyclization of N-Nitrosoanilines with Alkynes

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The DFT Studies to Mechanisms of the Cationic Cobalt(Ⅲ) Cat...