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Structure and Properties of Degradable Polybutylene Succinate Fibers

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Journal of Donghua University(English Edition) 2020年第3期37卷 191-198页

作者： hu Jiewen WANG Qianqian Zhu ping College of Textile&Clothing Qingdao UniversityQingdao 266071China Institute of Functional Textiles and Advanced Materials Qingdao UniversityQingdao 266071China State Key Laboratory of Bio-Fibers and Eco-Textiles Qingdao UniversityQingdao 266071China

Polybutylene succinate(PBS)fiber is a kind of synthetic fibers with excellent properties and biodegradability,which has been produced on a large scale in *** investigate the application properties of PBS fibers,the structure and properties were systematically studied in this *** microstructures and thermal properties of PBS fibers were analyzed by Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),scanning electron microscopy(SEM),thermo gravimetric(TG)and differential scanning calorimetry(DSC).The mechanical properties,chemical stability and dyeing properties of PBS fibers were also *** results show that PBS fibers areα-crystalline with a crystallinity of 58.56%.PBS fibers have an excellent thermal stability and the initial temperature of thermal degradation is 370℃.The tensile strength,the elongation at break,the elastic recovery rate at a fixed elongation(5%)and the moisture regain rate of PBS fibers are 29.57 cN/tex,90.94%,44.55%and 5.04%,*** chemical stability is as follows:alkali resistance

关键词： polybutylene succinate(PBS)fiber structure property mechanical property chemical stability dyeing property

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U型槽钢构件火焰矫正

价值工程 2014年第4期33卷 47-48页

作者：王荣辉赵斌王斌夏湖平杨琛杨杰谷旺军中原油田采油三厂濮阳252434 中原总机石油设备有限公司濮阳252434

本文为了阐述钢结构变形的主要种类并介绍U型槽钢构建焊缝变形的火焰矫正施工方法,在多年工作经验的基础上还结合了同行的相关资料,在实际的工作中作出了有益的尝试。

关键词： U型钢构件焊接变形火焰矫正

NH_(4)Cl-assisted preparation of single Ni sites anchored carbon nanosheet catalysts for highly efficient carbon dioxide electroreduction

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Journal of Materials Science & Technology 2023年第11期142卷 1-9页

作者： Dan ping Feng Yi Guiwei Zhang Shide Wu Shaoming Fang Kailong hu Ben Bin Xu Junna Ren Zhanhu Guo Henan Provincial Key Laboratory of Surface&Interface Science Henan Engineering Research Center of Chemical Engineering Separation Process IntensificationSchool of Material and Chemical EngineeringZhengzhou University of Light IndustryZhengzhou 450002China School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen 518055China Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Chemical&Biomolecular Engineering Integrated Composites Lab(ICL)University of TennesseeKnoxvilleTN 37996USA

Single-atomic transition metal-nitrogen codoped carbon(M-N-C)are efficient substitute catalysts for noble metals to catalyze the electrochemical CO_(2) reduction reaction(CO_(2)RR).However,the uncontrolled aggregations of metal and serious loss of nitrogen species constituting the M-N_(x) active sites are frequently observed in the commonly used pyrolysis ***,single-atomic nickel(Ni)-based sheet-like electrocatalysts with abundant Ni-N_(4) active sites were created by using a novel ammonium chloride(NH_(4)Cl)-assited pyrolysis *** aberration correction electron microscopy and X-ray absorption fine structure analysis clearly revealed that Ni species are atomically dispersed and anchored by N in Ni-N_(4) *** addition of NH_(4)Cl optimized the mesopore size to 7-10 nm and increased the concentrations of pyridinic N(3.54 wt%)and Ni-N_(4)(3.33 wt%)*** synergistic catalytic effect derived from Ni-N_(4) active sites and pyridinic N species achieved an outstanding CO_(2) RR performance,presenting a high CO Faradaic efficiency(FE_(CO))up to 98% and a large CO partial current density of 8.5 mA cm^(-2) at a low potential of-0.62 V ***,the FE_(CO) maintains above 80% within a large potential range from -0.43 to -0.73 V *** work provides a practical and feasible approach to building highly active single-atomic catalysts for CO_(2) conversion systems.

关键词： CO_(2)reduction Electrocatalyst Single-atomic ni NH_(4)Cl Pyridinic N

缺氧诱导因子-1α在早期糖尿病大鼠角膜上皮细胞中的表达

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国际眼科杂志 2006年第2期6卷 352-356页

作者：宋虎平惠延年王丽丽韩晓霞王海燕第四军医大学西京医院眼科全军眼科研究所中国陕西省西安市710032 中国陕西省西安市第四医院眼科 710004

目的:观察缺氧诱导因子-1α(HIF-1α)在早期糖尿病大鼠角膜上皮细胞中的表达以探讨其在糖尿病性角膜上皮细胞病变发生及发展中的作用。方法:用链脲佐菌素(STZ)制作糖尿病大鼠模型,在制模成功后1,2,4,6,8,10及12wk取眼球组织,以年龄匹配... 详细信息

目的:观察缺氧诱导因子-1α(HIF-1α)在早期糖尿病大鼠角膜上皮细胞中的表达以探讨其在糖尿病性角膜上皮细胞病变发生及发展中的作用。方法:用链脲佐菌素(STZ)制作糖尿病大鼠模型,在制模成功后1,2,4,6,8,10及12wk取眼球组织,以年龄匹配正常大鼠作为对照组,分别以免疫组织化学染色及Westernblotting方法检测角膜上皮细胞中HIF-1α表达的位置及表达量。结果:糖尿病模型诱导成功后1wk,角膜上皮细胞中即有HIF-1α表达,主要位于基底细胞的细胞核内,4wk时阳性细胞数大于1wk(21.80±1.93vs15.30±2.05),6～10wk达到高峰(6,8和10wk分别为49.00±2.82,90.80±4.23,51.40±5.21),12wk下降(14.40±2.06)。Westernblotting分析显示HIF-1α蛋白表达模式与免疫组织化学相似,1wk时即有表达,6～10wk达到高峰,12wk下降。结论:HIF-1α在早期糖尿病角膜上皮细胞中的瞬时高表达而不是持续表达,可能是早期糖尿病角膜上皮细胞病变的原因。

关键词：糖尿病并发症角膜上皮细胞病变缺氧诱导因子-1α

肝硬化彩色多普勒血流及超声造影时相变化的实验性研究

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疾病监测与控制 2017年第7期11卷 532-533页

作者：端学军黄毅斌胡萍香龙莎朱玉峰杨绿敏深圳市中医院超声科广东深圳518033

目的应用彩色多普勒流速剖面(CDVP)技术观察兔肝硬化模型门静脉血流变化,应用超声造影(CEUS)观察兔肝硬化模型肝实质造影时相变化,探讨CDVP技术结合CEUS评价肝硬化血流动力学变化的应用价值。方法选择雄性新西兰兔30只,分为实验组和对照... 详细信息

目的应用彩色多普勒流速剖面(CDVP)技术观察兔肝硬化模型门静脉血流变化,应用超声造影(CEUS)观察兔肝硬化模型肝实质造影时相变化,探讨CDVP技术结合CEUS评价肝硬化血流动力学变化的应用价值。方法选择雄性新西兰兔30只,分为实验组和对照组,实验组建立肝硬化动物模型,应用CDVP技术获取并比较两组门静脉平均血流速度、最大血流速度、门静脉血流量,应用低机械指数实时双幅超声造影及时间-强度分析曲线获取并比较两组肝实质造影剂到达时间、峰值强度、峰值强度减半时间。结果实验组经病理证实呈肝硬化改变,实验组门静脉平均流速、最大流速以及门静脉血流量分别为(10.89±2.56)cm/s,(13.65±3.11)cm/s和(71.35±20.31)ml/min,较对照组的(15.61±2.43)cm/s,(17.43±3.31)cm/s和(105.07±23.12)ml/min明显降低(P值均﹤0.05)。CEUS时间-强度曲线显示:实验组肝实质造影剂到达时间明显长于对照组:(6.33±1.03)s VS(3.31±1.07)s,实验组肝实质造影剂峰值强度、峰值强度减半时间明显小于对照组(74.65±11.05)d B VS(153.02±10.11)d B、(14.87±9.69)s VS(59.48±14.67)s,差异均有统计学意义(P均﹤0.05)。结论 CDVP技术及超声造影能够反映肝硬化血流状态,对评定肝硬化血流动力学变化有重要价值。

关键词：肝硬化超声造影门静脉彩色多普勒血流

Functional Characterization of a Type 4 Metallothionein Gene(CsMT4) in Cucumber

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Horticultural Plant Journal 2019年第3期5卷 120-128页

作者： Ling Duan Jingwen Yu Li Xu ping Tian Xin hu Xiaomei Song Yu Pan Key Laboratory of Horticulture Science for Southern Mountainous Regions Ministry of Education College of Horticulture and Landscape Architecture Southwest University

The excess amounts of heavy metals are toxic to various physiological processes in *** metallothioneins(MTs)are low molecular weight,cysteine-rich metal-binding proteins that play important roles in the detoxification of heavy metal *** this study,we characterized Cs MT4,a plant type 4 MT gene identified in a complementary DNA(cDNA)library prepared from young cucumber(Cucumis sativus)*** MT4encodes a 90 amino acid protein with a predicted molecular mass of 9.028 ***4 contains 17 cysteine residues in three highly conserved cysteine-rich *** contrast to the structures of other MTs,the highly conserved amino acid pattern CxCxxxCxCxxCxC is present in the middle of ***,CsMT4 was markedly induced in various tissues by various concentrations of Cd^(2+)and Zn^(2+)(>1.0 mmol·L^(-1)).Similar to AtMT4b function,heterologous expression of Cs MT4 in *** could also improved its tolerance to Cd^(2+)and led to increased uptake of Cd^(2+),and the rate of Cd^(2+)uptake was the highest in cells expressing a phytochelatin-like *** findings demonstrate that CsMT4 might be obviously induced by the metal stress in cucumber,and improves tolerance to Cd ions but not Zn ions when heterologously expressed in ***,and suggest that the composition and arrangement of N-terminal Cys-residues in MT4 are associated with their binding capacity and preference for different metal ions.

关键词： Cucumber CsMT4 Metallothionein Metal-binding properties Heterologous expression

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黑逍遥散对东莨菪碱致痴呆小鼠模型的影响

中国中医药信息杂志 2013年第10期20卷 35-37页

作者：吴红彦李海龙张云赵鹏顾静车敏王虎平甘肃中医学院甘肃兰州730000 甘肃省中药药理与毒理学重点实验室甘肃省中药新产品创制工程实验室甘肃兰州730000 甘肃省中医院甘肃兰州730050

目的观察黑逍遥散对东莨菪碱致痴呆小鼠模型的影响,探讨其防治痴呆的作用机制。方法昆明种小鼠50只,随机分为空白组、模型组、黑逍遥散组、逍遥散组、精简方组,每组10只。采用氢溴酸东莨菪碱腹腔注射诱发小鼠记忆障碍建立模型,各药物组... 详细信息

目的观察黑逍遥散对东莨菪碱致痴呆小鼠模型的影响,探讨其防治痴呆的作用机制。方法昆明种小鼠50只,随机分为空白组、模型组、黑逍遥散组、逍遥散组、精简方组,每组10只。采用氢溴酸东莨菪碱腹腔注射诱发小鼠记忆障碍建立模型,各药物组每日给予相应的原药材水煎液2.314 g/kg,空白组和模型组给予等量生理盐水,每日灌胃1次,连续灌胃10 d。给药后第6、8日采用水迷宫法、跳台法及避暗法进行行为学能力训练,给药后第10日进行行为学能力测试,完毕后处死动物,采集脑组织并测定脑组织中乙酰胆碱酯酶(AchE)和胆碱乙酰转移酶(ChAT)的活性。结果与模型组比较,黑逍遥散组、逍遥散组及精简方组均能减少水迷宫测试中错误次数,缩短潜伏时间;减少在跳台、避暗测试中的电击次数,延长潜伏期时间;均能升高脑组织匀浆ChAT活性,降低AchE活性(P<0.01,P<0.05),其中以黑逍遥组效果最为明显。结论黑逍遥散及其类方具有防治老年性痴呆的作用。

关键词：黑逍遥散老年性痴呆动物行为氢溴酸东莨菪碱乙酰胆碱酯酶胆碱乙酰转移酶小鼠

Additive manufacturing of Cu-AI-Mn shape memory alloy with enhanced superelasticity

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Rare Metals 2023年第12期42卷 4234-4245页

作者： Meng-Wei Wu Zhuo-Fan hu Bing-Bing Yang Ying Tao Rui-ping Liu Chun-Mei Ma Lei Zhang Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Department of Mechanical Engineering University of Alaska FairbanksFairbanks 99775-5905USA

The Cu-based shape memory alloy(SMA)with highly oriented columnar crystals is an ideal candidate for the commercial application,especially the ones obtained through rapid cooling via additive manufacturing *** this work,Cu_(71)Al_(18)Mn_(11)(at%)shape memory alloy with strongtexture columnar grains was successfully prepared by selective laser melting(SLM).An L27(313)orthogonal array was designed to systematically investigate the effects of laser power,scanning speed,scanning spacing,layer thickness and their interactions on the forming quality of Cu_(71)Al_(18)Mn_(11)***_(71)Al_(18)Mn_(11)alloys with density of 7.3204 g·cm^(-3)and relative density of 99.18%were successfully prepared when the laser power,scanning speed,scanning distance and layer thickness were 240 W,1000 mm·s^(-1),0.11 mm and 25μm,the transformation onset temperature(Ms),martensite phase transformation termination temperature(Mf),austenite phase transformation onset temperature(AS)and austenite phase transformation termination temperature(Af)are-21.84,-26.04,-15.75 and-12.36℃,*** compression strength and fracture strain along the building direction(BD)were significantly superior to the scanning direction(SD),while the superelasticity of compression along the SD reached 2.50%,which was better than that of2.32%along *** mechanical property and superelasticity anisotropy due to the formation of columnar grains and texture were *** study shows that SLM is a proposed method for the preparation of Cu-Al-Mn SMAs with high superelasticity,which provides a new strategy for enhancing the shape memory alloy superelasticity.

关键词： Shape memory alloy(SMA) Selective laser melting(SLM) Columnar grains Superelasticity properties

Adaptive sliding mode control of modular self-reconfigurable spacecraft with time-delay estimation

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Defence Technology（防务技术） 2022年第12期18卷 2170-2180页

作者： Xin-hong Li Zhi-bin Zhang Ji-ping An Xin Zhou Gang-xuan hu Guo-hui Zhang Wan-xin Man Department of Aerospace Science and Technology Space Engineering UniversityNo.1 BaYi RoadHuaiRou DistrictBeijing101416China Beijing Institute of Remote Sensing Information Beijing100192China

The reconstruction control of modular self-reconfigurable spacecraft (MSRS) is addressed using an adaptive sliding mode control (ASMC) scheme based on time-delay estimation (TDE) technology. In contrast to the ground, the base of the MSRS is floating when assembled in orbit, resulting in a strong dynamic coupling effect. A TED-based ASMC technique with exponential reaching law is designed to achieve high-precision coordinated control between the spacecraft base and the robotic arm. TDE technology is used by the controller to compensate for coupling terms and uncertainties, while ASMC can augment and improve TDE’s robustness. To suppress TDE errors and eliminate chattering, a new adaptive law is created to modify gain parameters online, ensuring quick dynamic response and high tracking accuracy. The Lyapunov approach shows that the tracking errors are uniformly ultimately bounded (UUB). Finally, the on-orbit assembly process of MSRS is simulated to validate the efficacy of the proposed control scheme. The simulation results show that the proposed control method can accurately complete the target module’s on-orbit assembly, with minimal perturbations to the spacecraft’s attitude. Meanwhile, it has a high level of robustness and can effectively eliminate chattering.

关键词： Adaptive sliding mode control(ASMC) Time delay control Time delay estimation Modular self-reconfigurable spacecraft Uncertainty Coordinated control