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六自由度机械臂的动力学参数辨识

制造业自动化 2021年第3期43卷 35-39页

作者：张师源戴骏邓华中南大学高性能复杂制造国家重点实验室长沙410083 中南大学机电工程学院长沙410083

针对六自由度机械臂的动力学参数较多,一般需要多次辨识,且辨识精度有限问题,提出一种六自由度机械臂动力学动力学参数的一次性辨识方法。首先将六自由度机械臂的前后三个关节分为两部分,采用遗传算法分别优化设计激励轨迹信号,并进行... 详细信息

针对六自由度机械臂的动力学参数较多,一般需要多次辨识,且辨识精度有限问题,提出一种六自由度机械臂动力学动力学参数的一次性辨识方法。首先将六自由度机械臂的前后三个关节分为两部分,采用遗传算法分别优化设计激励轨迹信号,并进行动力学参数的一次性整体辨识,充分考虑了关节之间的耦合作用,消除了由于多次辨识实验所带来的实验条件不一致的误差。然后利用最小二乘法确定辨识参数的初值,避免了初值取值不当所带来辨识精度有限的问题。最后,通过设计动力学参数辨识实验,验证了所提方法的有效性。

关键词：动力学模型优化算法参数辨识

碳纤维负载零价铁的制备及其去除水溶液中的六价铬

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工程科学学报 2015年第5期37卷 626-632页

作者：袁飞冯雅丽王维大李浩然黄玲张士元北京科技大学土木与环境工程学院北京100083 中国科学院过程工程研究所生化工程国家重点实验室北京100190 华北科技学院环境工程学院北京101601

以碳纤维作为载体,采用电沉积法制备碳纤维负载零价铁(PCF-ZVI),利用扫描电镜、能谱仪及X射线衍射仪对其进行了表征,并考察了其对水溶液中Cr(VI)的去除效果.实验结果表明:碳纤维负载零价铁对水溶液中的Cr(VI)具有很好的去除效果.当铁碳... 详细信息

以碳纤维作为载体,采用电沉积法制备碳纤维负载零价铁(PCF-ZVI),利用扫描电镜、能谱仪及X射线衍射仪对其进行了表征,并考察了其对水溶液中Cr(VI)的去除效果.实验结果表明:碳纤维负载零价铁对水溶液中的Cr(VI)具有很好的去除效果.当铁碳质量比为2∶1,投加量(以Fe0计)为2 g·L-1,Cr(VI)初始质量浓度为20 mg·L-1,p H值为5,反应时间40min后,Cr(VI)的去除率可达99.96%,碳纤维上负载的零价铁对Cr(VI)的还原过程为准一级动力学,并且还原速率与反应温度的关系符合Arrhenius定律,反应活化能为20.683 k J·mol-1.

关键词：重金属废水电沉积碳纤维零价铁还原铬

Upcycling of polyethylene terephthalate to1,4-cyclohexanedimethanol in water

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Science China Chemistry 2025年

作者： Shuhui Fang Zhiwen Gao Xinrui shi Min zhang Wei zhang Yue Liu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University Engineering Center for Sustainable Carbon Science and Technology East China Normal University Institute of Eco-Chongming

The recycling of waste polyethylene terephthalate（PET）, an extensively used polymer as plastic and fiber materials, has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment. Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol（CHDM）, an important chemical in the production of advanced polyesters, predominantly use organic solvents, such as alcohols or dioxane. Herein, we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent. In this process, PET is sequentially hydrolyzed in water, hydrogenated to 1,4-cyclohexane dicarboxylic acid（CHDA）, and then reduced to CHDM. The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate. A Pd-based catalyst（e.g., Pd/C） selectively hydrogenates the arene ring of the PET monomer, terephthalic acid intermediate, and a Ru-Sn/C bimetallic catalyst reduces its COOH to CH2OH group. At optimized reaction conditions, a complete conversion of PET and 80.1% yield of CHDM are obtained. Alternatively, this approach can also efficiently produce CHDA from PET, with a yield up to 86.4%.

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Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

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Neural Regeneration Research 2025年第1期20卷 67-81页

作者： Yubo Wang Tingli yuan Tianjie Lyu Ling zhang Meng Wang Zhiying He Yongjun Wang Zixiao Li Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Shanghai Engineering Research Center of Stem Cells Translational Medicine ShanghaiChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghaiChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger ***,in particular,bears a high burden of stroke *** recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its *** review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and ***,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell ***,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient *** cell therapy may potentially become an important component of ischemic stroke treatment.

关键词： cell therapy immune cell inflammatory ischemic stroke stem cell

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长江口拦门沙段滩涂形态调整及冲淤响应机制

水电能源科学 2023年第1期41卷 26-29页

作者：李溢汶张诗媛上海勘测设计研究院有限公司上海200434

为研究长江口拦门沙段重要滩涂对水沙条件改变及人类活动的响应机制,以横沙浅滩、九段沙及南汇东滩为例,分析了拦门沙段重要滩涂的平面形态调整特点及其对环境因素变化的响应过程,并建立了代表滩涂面积与汛期水沙条件间的经验关系。结... 详细信息

为研究长江口拦门沙段重要滩涂对水沙条件改变及人类活动的响应机制,以横沙浅滩、九段沙及南汇东滩为例,分析了拦门沙段重要滩涂的平面形态调整特点及其对环境因素变化的响应过程,并建立了代表滩涂面积与汛期水沙条件间的经验关系。结果表明,横沙浅滩、九段沙及南汇东滩近年来滩涂平面形态呈萎缩态势、沙尾总体滞涨,且横沙浅滩及九段沙有不同程度的串沟发育现象;横沙浅滩面积与前7年平均的汛期水流冲刷强度具有良好的幂函数关系,反映了浅滩面积随水沙条件变化的滞后响应过程;河口治理工程对滩涂局部的守护能较快抑制水沙条件改变所引起的冲刷,但其对周边区域可能产生缓慢、长期的累积影响。

关键词：浅滩演变长江口水沙条件冲淤响应工程影响

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan shi Qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

阿尔泰蝠蛾(鳞翅目:蝙蝠蛾科)幼虫低温胁迫转录组分析

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应用昆虫学报 2021年第5期58卷 1113-1125页

作者：孙涛张示渊张婷婷王岩石河子大学医学院石河子832000 八师石河子市总医院(石河子大学第三附属医院石河子市人民医院)石河子832000 石河子大学动物科技学院石河子832000 石河子大学畜牧学博士后流动站石河子832000

【目的】本研究旨在通过转录组测序技术分析低温胁迫引起的阿尔泰蝠蛾Hepialus altaicola Wang幼虫基因转录差异及上调表达基因的主要功能类群和参与的主要代谢通路。【方法】采用Illumina HiSeqTM 2500测序平台对阿尔泰蝠蛾幼虫进行转... 详细信息

【目的】本研究旨在通过转录组测序技术分析低温胁迫引起的阿尔泰蝠蛾Hepialus altaicola Wang幼虫基因转录差异及上调表达基因的主要功能类群和参与的主要代谢通路。【方法】采用Illumina HiSeqTM 2500测序平台对阿尔泰蝠蛾幼虫进行转录组测序、组装,利用Blast软件进行数据库比对和基因功能注释,用DEGSeqR软件包分析4℃低温处理与室内适温饲养试虫的差异表达基因,并对上调表达基因进行GO和KEGG代谢途径富集分析。【结果】经序列拼接后共获得100300个unigenes,总长度81600309 bp,平均长度813 bp,N50长度1719 bp。与7大数据库同源比对,共获得34691(34.59%)条unigenes。低温胁迫转录组分析得到11569个差异表达基因(DEGs),7158条基因上调,4411条基因下调。富集到47个GO类群,217个KEGG途径。其中代谢过程、催化、结合活性类群占有重要比例,核糖体、碳代谢、剪接体等途径显著富集。另外,热激蛋白、昆虫表皮蛋白、海藻糖酶、超氧化物歧化酶等非生物胁迫相关基因显著上调表达。【结论】阿尔泰蝠蛾幼虫低温胁迫转录组分析揭示,代谢过程、细胞过程、生物调节、对刺激的反应等生物学过程相关基因和部分非生物胁迫响应基因显著上调表达,提示蝠蛾幼虫可能从抗氧化防御、分子伴侣、体温调节和维持细胞的渗透平衡等多方面应对低温胁迫。

关键词：阿尔泰蝠蛾转录组基因注释低温胁迫差异表达基因

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong shi Chenhui Han Heng zhang Fenrong Liu Haorun Li Yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods

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参附注射液改善脓毒症休克的疗效观察

现代药物与临床 2017年第6期32卷 1034-1038页

作者：张诗元天津中医药大学第一附属医院急症部天津300381

目的观察参附注射液改善脓毒症休克的临床疗效。方法选取2014年10月—2016年3月天津中医药大学第一附属医院收治的脓毒症休克患者71例,所有患者按随机数字表法分为对照组(35例)和治疗组(36例)。对照组给予积极维持循环、机械通气、控制... 详细信息

目的观察参附注射液改善脓毒症休克的临床疗效。方法选取2014年10月—2016年3月天津中医药大学第一附属医院收治的脓毒症休克患者71例,所有患者按随机数字表法分为对照组(35例)和治疗组(36例)。对照组给予积极维持循环、机械通气、控制血糖、镇静等治疗。治疗组在对照组基础上静脉滴注参附注射液,100 m L加入5%葡萄糖250m L中,1次/d。两组均治疗7 d。观察并比较两组的中心静脉血氧饱和度(Sc VO2)、乳酸(Lac)、24 h乳酸清除率、氧输送量(DO2)、氧消耗量(VO2)、氧摄取率(O2ER%),序贯器官衰竭估计(SOFA)评分、急性生理功能和慢性健康状况评分系统Ⅱ(APACHEⅡ)评分、重症监护室(ICU)住院时间和28 d死亡率。结果治疗后,两组Sc VO2和Lac均显著下降,同组治疗前后比较差异有统计学意义(P<0.05);且治疗组这些观察指标明显低于对照组,两组比较差异具有统计学意义(P<0.05)。治疗后,治疗组24 h乳酸清除率明显高于对照组,两组比较差异有统计学意义(P<0.05)。治疗后,两组DO2水平均明显上升,同组治疗前后比较差异有统计学意义(P<0.05),而VO2和O2ER%改善不明显;且治疗组DO2水平明显高于对照组,两组比较差异具有统计学意义(P<0.05)。两组SOFA评分和APACHEⅡ评分均明显降低(P<0.05),同组治疗前后比较差异有统计学意义(P<0.05);且治疗组这些观察指标明显低于对照组,两组比较差异具有统计学意义(P<0.05)。对照组和治疗组ICU住院时间比较差异无统计学意义。对照组和治疗组死亡率比较差异无统计学意义。结论参附注射液可改善脓毒症休克治疗,增加氧输送量,改善组织灌注状态,降低SOFA评分和APACHEⅡ评分,具有一定的临床推广应用价值。

关键词：参附注射液脓毒症休克氧代谢 SOFA评分 APACHEⅡ评分