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一种多模态振动系统的位置控制方法

机电工程技术 2024年第7期53卷 107-111页

作者：张志铭赵璞岳龙旺河南工业大学机电工程学院郑州450001

以多模态柔性系统为研究对象,针对多模态柔性系统在操作时产生振动,影响操作性能和定位精度的问题,提出了一种基于振动叠加原理和位置控制原理对柔性系统进行主动振动抑制的方法。首先利用振动叠加原理,对系统的振动进行分解,讨论了系... 详细信息

以多模态柔性系统为研究对象,针对多模态柔性系统在操作时产生振动,影响操作性能和定位精度的问题,提出了一种基于振动叠加原理和位置控制原理对柔性系统进行主动振动抑制的方法。首先利用振动叠加原理,对系统的振动进行分解,讨论了系统的振动状态与能量表达;接着以系统的振动能量为指标,给出了抑制振动的输入位移的一种选择方法;然后为保证多模态系统在减振完成后的定位精度,提出了一种位置控制方法。为了验证所提出的振动抑制方法的有效性,首先在ADAMS中建立了单输入多模态系统的模型,然后导入Simulink中进行联合仿真,讨论此振动抑制方法的有效性以及其抑制特性。仿真结果表明:所提出的方法的减振效果良好,对比传统的控制方法来说,有较高的鲁棒性,有效抑制了系统的振动并且保证了系统的定位精度。

关键词：多模态系统位置控制振动叠加振动抑制

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牵张力对小鼠骨髓间充质干细胞成骨分化能力的作用及机制研究

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东南大学学报（医学版） 2024年第2期43卷 171-176页

作者：张志明叶芝魁蒋校文南方医科大学口腔医学院广东广州510515 郴州市第一人民医院口腔科湖南郴州423000 湘南学院附属医院口腔科湖南郴州423000

目的:探讨牵张力作用对小鼠骨髓间充质干细胞(BMSCs)成骨分化能力的影响及作用机制。方法:原代分离并培养小鼠BMSCs,并将BMSCs分为对照组、牵张力作用6 h组、牵张力作用12 h组和牵张力作用12 h+雷帕霉素(Rap)组,采用多单元细胞拉伸装置... 详细信息

目的:探讨牵张力作用对小鼠骨髓间充质干细胞(BMSCs)成骨分化能力的影响及作用机制。方法:原代分离并培养小鼠BMSCs,并将BMSCs分为对照组、牵张力作用6 h组、牵张力作用12 h组和牵张力作用12 h+雷帕霉素(Rap)组,采用多单元细胞拉伸装置施加动态牵张力进行干预。生化法检测细胞中碱性磷酸酶(ALP)活性;ELISA法检测细胞培养液上清中骨膜蛋白(POSTN)含量;RT-qPCR检测细胞中Runt相关转录因子2(RUNX2)、骨钙素(OCN)、Osterix和骨桥蛋白(OPN)mRNA表达水平;Western blot检测细胞中RUNX2、OCN、Osterix、OPN、POSTN、哺乳动物雷帕霉素靶蛋白(mTOR)和磷酸化mTOR(p-mTOR)蛋白表达水平。结果:与对照组比较,牵张力作用6 h组和12 h组细胞中ALP活性及RUNX2、Osterix、OCN和OPN mRNA表达水平均显著升高(均P0.05)。结论:牵张力通过介导POSTN表达调控mTOR信号通路激活,从而促进BMSCs成骨分化。

关键词：牵张成骨骨髓间充质干细胞骨膜蛋白哺乳动物雷帕霉素靶蛋白成骨分化

Significance of the potential role of pharmacological MRI （phMRI） in diagnosis of Parkinson＇s disease

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Frontiers in Biology 2012年第4期7卷 307-312页

作者： Feng YUE Piu CHAN zhiming zhang Department of Neurobiology and Neurology Beijing Institute of Geriatrics Xuanwu Hospital of Capital University of Medical Sciences Beijing 100053 China Department of Anatomy and Neurobiology University of Kentucky College of Medicine Lexington KY 40536 USA

The initial diagnosis of Parkinson＇s disease （PD） is currently based on a clinical assessment. Many patients who receive an initial diagnosis of PD have parkinsonian features related to other diseases such as essential tremor, vascular parkinsonism and atypical parkinsonian disorder. It has been challenging to differentiate PD from those disorders, especially in the early disease stages, due to an overlap of clinical signs and symptoms. Therefore, there is a great need for development of noninvasive, highly sensitive, and widely available imaging methods that can potentially be used to assistant physicians to make more accurate diagnosis of the disease; and to longitudinally monitor treatment of PD. Recent advance of pharmacological MRI （phMRI） technology allows non-invasively mapping functional stages for nigrostriatal dopamine （DA） system. This article aims to review research findings primarily from our group in nonhuman primates modeling the neurodegenerative disease on the value of phMRI techniques in the diagnosis of PD.

关键词： pharmacological MRI (phMRI) Parkinson's disease phMRI techniques

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基于熵理论的能量调节性能研究

储能科学与技术 2024年第5期13卷 1584-1591页

作者：孙振新张秩鸣马俯波蒋丛进杜昊易陈换军张玉魁国家能源集团新能源技术研究院有限公司北京102211

在高比例风、光接入背景下,电力系统面临日益突出的能量调节压力。当下,储能作为构建新型电力系统的重要支撑面临配置成本高,利用率不足等问题。本工作基于克劳修斯熵理论,构建出一种可用于量化及评价能源系统能量-时间解耦能力的物理... 详细信息

在高比例风、光接入背景下,电力系统面临日益突出的能量调节压力。当下,储能作为构建新型电力系统的重要支撑面临配置成本高,利用率不足等问题。本工作基于克劳修斯熵理论,构建出一种可用于量化及评价能源系统能量-时间解耦能力的物理量——功率熵,系统研究了功率熵与功率、时长、容量等储能配置关键决策变量间的内在关系,发现功率熵与多种关键决策变量间具有一致的正相关关系,可用于衡量储能综合调节性能,同时功率熵还兼具体现储能功率时序特征的功能。基于功率熵所展现的特性,本工作建立了基于功率熵的电力系统储能配置优化分析方法,并通过模拟案例分析对功率熵在储能配置优化中的作用进行了验证。结果显示,在不同的储能配置下,系统功率熵增不同,系统优化方向是由储能引入系统的功率熵增逐渐减小的方向,也即储能调节性能冗余逐渐减少的方向。功率熵的概念为未来电力系统的储能配置优化,乃至综合能源系统内部多种能源形式的配置优化提供了一种新思路。

关键词：储能技术优化配置克劳修斯熵功率熵

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Extended structural materials constructed from sulfate-centered Preyssler-type polyoxometalate with excellent electrocatalytic property

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Chinese Chemical Letters 2018年第9期29卷 1409-1412页

作者： Na zhang Luying Hong Aifang Geng Jinghui Yan Shuang Yao zhiming zhang College of Chemistry and Environmental Engineering Changchun University of Science and Technology Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical Engineering Tianjin University of Technology

Sulfate-centered Preyssler-type polyoxometalate was used as the precursor to react with transition metal cations and organic ligand for constructing inorganic-organic hybrid materials {H[Ni2（H2O）4（Htrz）3]2（KSsW30O110）}·18H2O （trz = 1,2,4-triazole）（1）, which was characterized by single crystal X-ray diffraction analysis, energy-dispersive X-ray （EDX）, power X-ray diffraction （PXRD）, IR spectra and thermogravimetric （TG） analyses. In 1, the cylindrical vacancy of the inorganic crown-type anion （SsW30Ouo） captures a K^＋ ion resulting in the anion {KS5W3oO110）^9-, which was further connected by dimeric [Ni2（H2O）4（Htrz）3]2 metal-organic units into an one-dimensional （1D） chain-like structure. These 1D chains are further packed to form a three-dimensional （3D） supramolecular structure via Hbonding interactions. Here, the sulfate-centered Preyssler-typepolyoxometalate was firstly used to coordinate with transition metal cations and introduced into the inorganic-organic hybrid materials. Electrocatalytic study indicates that compound I exhibits good electrocatalytic activity toward reduction of H2O2 and NO2^-.

关键词： Preyssler-type Polyoxometalate Transition metal Supramolecular structure Electrocatalytic activity

Effects of MeV Fe Ions Irradiation on the Microstructure and Property of Nuclear Grade 304 Stainless Steel:Characterized by Positron Annihilation Spectroscopy,Transmission Electron Microscope and Nanoindentation

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Acta Metallurgica Sinica(English Letters) 2021年第12期34卷 1695-1703页

作者： Honglin Yan zhiming zhang Jianqiu Wang Bright O.Okonkwo En-Hou Han Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Nuclear grade 304 stainless steel was irradiated by 3.5 MeV Fe ions,with fluxes of 3.05E+15 ions/cm^(2)and 1.55E+16 ions/cm^(2).Irradiation effects were studied by positron annihilation spectroscopy(PAS),transmission electron microscope(TEM)and nanoindentation *** results showed that different types of defects were produced after irradiation and that there was significant variance in defects formed when the samples were subjected to different irradiation *** characterization showed that the irradiation-induced dislocation loops enlarged in average size,but decreased in number density at higher irradiation *** test showed obvious irradiation hardening phenomenon,which was in good agreement with the PAS and TEM *** hardening effect increased with an increase in irradiation dose and saturation occurred with an increase in irradiation dose from 3.2 to 16 *** statistical analysis showed that barrier strength of the Frank loop depends on the loop size and density produced by the ion irradiation.

关键词： Stainless steel Irradiation hardening Positron annihilation Nanoindentation

Aortic heterogeneity across segments and under high fat/salt/glucose conditions at the single-cell level

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National Science Review 2020年第5期7卷 881-896页

作者： Dongxu He Aiqin Mao Chang-Bo Zheng Hao Kan Ka zhang zhiming zhang Lei Feng Xin Ma Wuxi School of Medicine and School of Food Science and Technology Jiangnan University School of Biotechnology Jiangnan University School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical University

The aorta, with ascending, arch, thoracic and abdominal segments, responds to the heartbeat, senses metabolites and distributes blood to all parts of the body. However, the heterogeneity across aortic segments and how metabolic pathologies change it are not known. Here, a total of 216 612 individual cells from the ascending aorta, aortic arch, and thoracic and abdominal segments of mouse aortas under normal conditions or with high blood glucose levels, high dietary salt, or high fat intake were profiled using single-cell RNA sequencing. We generated a compendium of 10 distinct cell types, mainly endothelial(EC), smooth muscle (SMC), stromal and immune cells. The distributions of the different cells and their intercommunication were influenced by the hemodynamic microenvironment across anatomical segments,and the spatial heterogeneity of ECs and SMCs may contribute to differential vascular dilation and constriction that were measured by wire myography. Importantly, the composition of aortic cells, their gene expression profiles and their regulatory intercellular networks broadly changed in response to high fat/salt/glucose conditions. Notably, the abdominal aorta showed the most dramatic changes in cellular composition, particularly involving ECs, fibroblasts and myeloid cells with cardiovascular risk factor-related regulons and gene expression networks. Our study elucidates the nature and range of aortic cell diversity,with implications for the treatment of metabolic pathologies.

关键词： aorta single-cell RNA sequencing cardiovascular disease

祁连山北麓荒漠草原5种优势植物生物量与土壤养分特征

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干旱区地理 2024年第4期47卷 662-671页

作者：张志明孙小妹包段红姚宝辉王志成苏军虎甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃省草业工程实验室中-美草地畜牧业可持续发展研究中心甘肃兰州730070 甘肃农业大学新西兰梅西大学草地生物多样性研究中心甘肃兰州730070 甘肃农业大学资源与环境学院甘肃兰州730070

为明晰荒漠草原优势植物的植物生物量与土壤养分关系,研究选取祁连山北麓肃北区域荒漠草原骆驼蓬(Peganum harmala)、狗尾草(Setaria viridis)、中华羊茅(Festuca sinensis)、碱茅(Pucci-nellia distans)和冰草(Agropyron cristatum)5种优势植物,测定该其生物量和根际土壤养分,探究其植物生物量分配及其与土壤养分间的关系。结果表明:(1)5种优势植物间总生物量和根冠比差异显著(P冰草>中华羊茅>骆驼蓬>狗尾草。(2)5种植物根际土壤有机碳、碱解氮、速效钾、全氮、全磷、全钾及其化学计量特征均存在显著差异(P狗尾草>冰草>骆驼蓬>中华羊茅。(3)不同植物生物量、根冠比及土壤养分变异性不一致,骆驼蓬、狗尾草和中华羊茅的根际土壤全钾与碱茅和冰草的根际土壤含水量等均为弱变异,而土壤养分及其化学计量特征为中等变异。5种优势植物的生物量与根际土壤碱解氮和全钾呈正相关性(P<0.05)。可见荒漠草原生态系统中植物生物量分配和根际土壤养分在生活史和物种间的差异较大,今后应根据不同优势植物养分需求,合理施肥来修复退化的荒漠生态系统。

关键词：荒漠草原生物量根冠比土壤养分特征祁连山北麓

LHRH/TAT dual peptides-conjugated polymeric vesicles for PTT enhanced chemotherapy to overcome hepatocellular carcinoma

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Chinese Chemical Letters 2020年第12期31卷 3121-3126页

作者： Yu Qin Qing Guo Shengjie Wu Chenlu Huang zhiming zhang Li zhang Linhua zhang Dunwan Zhu Tianjin Key Laboratory of Biomedical Materials Key Laboratory of Biomaterials and Nanotechnology for Cancer ImmunotherapyInstitute of Biomedical EngineeringChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300192China

Combination therapy such as photothermal therapy(PTT)enhanced chemotherapy is regarded as a promising strategy for cancer ***,we developed redox-responsive polymeric vesicles based on the amphiphilic triblock copolymer *** avoid the limited therapeutic effect of chemotherapeutic drugs caused by systemic exposures and drug resistance,the redox-sensitive polymeric vesicles were cargoed with two chemotherapeutics:doxorubicin(DOX)and paclitaxel(PTX).Besides,indocyanine green(ICG)was encapsulated,and cell-penetrating peptides and LHRH targeting molecule were modified on the surface of polymeric *** results indicated that the polymeric vesicles can load different kinds of drugs with high drug loading content,trigger drug release in responsive to the reductive environment,realize high cellular uptake via dual peptides and laser irradiation,and achieve higher cytotoxicity via chemo-photothermal combination ***,the redox-responsive LHRH/TAT dual peptides-conjugated PTX/DOX/ICG co-loaded polymeric micelles exhibited great potential in tumor-targeting and chemo-photothermal therapy.

关键词： Redox-responsive Polymeric vesicles Chemotherapy Photothermal therapy Combination therapy