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异海松酰(胺)基硫脲类衍生物的合成及其生物活性评价

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有机化学 2017年第3期37卷 731-738页

作者：刘娟娟卢言菊王婧毕良武赵振东中国林业科学研究院林产化学工业研究所生物质化学利用国家工程实验室国家林业局林产化学工程重点开放性实验室江苏省生物质能源与材料重点实验室南京210042 中国林业科学研究院林业新技术研究所北京100091

为了开发具有较高生物活性的异海松酸类衍生物,将硫脲结构拼接到异海松酸骨架上,设计合成了15个未见报道的异海松酰(胺)基硫脲类化合物,其结构经FT-IR、~1h NMR、^(13)C NMR和hRMS或元素分析确证.对化合物进行了初步的抑菌和抗癌活性测... 详细信息

为了开发具有较高生物活性的异海松酸类衍生物,将硫脲结构拼接到异海松酸骨架上,设计合成了15个未见报道的异海松酰(胺)基硫脲类化合物,其结构经FT-IR、~1h NMR、^(13)C NMR和hRMS或元素分析确证.对化合物进行了初步的抑菌和抗癌活性测试,大多数化合物对白色念珠菌表现出显著的抑制活性,且活性高于异海松酸.在浓度为100μmol/L时,部分化合物对人黑色素瘤(A375)和前列腺癌(PC-3)癌细胞具有明显的增殖抑制作用,尤其化合物N-异海松酰基-N′-(3-甲基苯基)硫脲(3c)和N-异海松酰胺基-N'-(4-氟苯基)硫脲(6b)对癌细胞的抑制率达到90%以上.

关键词：异海松酸酰基硫脲抑菌活性抗癌活性构效关系

Tri-directional shaking table tests of vibration sensitive equipment with static dynamics interchangeable-ball pendulum system

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 103-112页

作者： C.S. Tsai Yung-Chang Lin Wen-Shin Chen h.C. Su D G epartment of Civil Engineering Feng Chia University Taichung Chinese Taipei Graduate Institute of Civil and hydraulic Engineering Feng Chia University Taichung Chinese Taipei Department of Water Resources Engineering and Conservation Feng Chia University Taichung Chinese Taipei

Recently, the high-tech industry has become a key industry for economic development in many countries. however, vibration sensitive equipment located in these industrial buildings is vulnerable during earthquakes, which may cause huge economic loss. In this study, an innovative isolator for safeguarding the vibration sensitive equipment, namely, the static dynamics interchangeable^all pendulum system （SDI-BPS） is proposed and investigated to examine its protective capability for the vibration sensitive equipment during earthquakes through a series of tri-directional shaking table tests. The experimental results illustrate that the SDI-BPS isolator can provide significant damping to rolling types of base isolation systems for reducing the bearing displacement and size, and avoid the stress concentration, which can cause damage or scratches on the rolling surface of the isolator, to prolong its life span of service. The SDI-BPS isolator also provides excellent capability in protecting the vibration sensitive equipment and exhibits a stable behavior under long terms of service loadings and earthquakes.

关键词： ball pendulum system critical equipment base isolation vibration sensitive equipment base isolator passive control earthquake engineering structural control

海上风电接入柔直系统交流侧故障特征及对保护的影响分析

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电力系统保护与控制 2021年第20期49卷 20-32页

作者：郑黎明贾科毕天姝侯来运方煜新能源电力系统国家重点实验室(华北电力大学) 北京102206 国家电网南京供电公司江苏南京210019

柔性直流输电是解决大规模海上风电远距离外送问题的首选方案。然而,柔直送端交流系统发生故障时,线路两侧短路电流均由电力电子换流器提供,系统的故障特征发生了根本性变化,直接导致传统保护性能的下降、甚至不正确动作,影响系统的安... 详细信息

柔性直流输电是解决大规模海上风电远距离外送问题的首选方案。然而,柔直送端交流系统发生故障时,线路两侧短路电流均由电力电子换流器提供,系统的故障特征发生了根本性变化,直接导致传统保护性能的下降、甚至不正确动作,影响系统的安全运行。因此,针对永磁风电场经柔直外送的拓扑,分析了柔直送端交流侧故障的特征,并结合交流侧故障穿越控制目标提出了换流器短路电流解析表达方法。理论分析表明,当风电场弱出力时,仅由柔直换流器提供短路电流,且短路电流呈现出幅值受限特性、甚至低于额定电流;当风电场正常出力时,柔直换流器与风电场均提供短路电流,且二者控制目标不同,两侧同相别短路电流必然存在相角差。基于故障特征的研究,对现场常用的保护原理进行了性能分析,获知了线路距离保护、差动保护均会存在性能下降的问题。在PSCAD/EMTDC中建立了风电柔直送出系统的精细化模型,验证了理论分析的正确性,为现场保护配置以及保护新原理的研究提供了理论基础。

关键词：风电场柔性直流交流故障故障特征分析

硼氧酸盐(K_2O·CaO·4B_2O_3·12h_2O)的合成与表征

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东北大学学报（自然科学版） 2011年第3期32卷 400-402,414页

作者：毕颖田彦文王国胜刘丹东北大学材料与冶金学院辽宁沈阳110819 沈阳化工大学化学工程学院辽宁沈阳110142

以氯化钙、四硼酸钾为原料,以水为溶媒,采用易于工业化、无污染的水溶液法制备一种新型硼酸钾钙复盐.该方法工艺条件为:去离子水450ml,四硼酸钾和氯化钙的质量比65∶7.5,搅拌转速400r/min,45℃反应3h.通过化学分析、红外光谱、X射线衍... 详细信息

以氯化钙、四硼酸钾为原料,以水为溶媒,采用易于工业化、无污染的水溶液法制备一种新型硼酸钾钙复盐.该方法工艺条件为:去离子水450ml,四硼酸钾和氯化钙的质量比65∶7.5,搅拌转速400r/min,45℃反应3h.通过化学分析、红外光谱、X射线衍射、扫描电镜等分析测试方法,对所合成的复盐进行了分析和表征.考察了反应温度对晶体形貌的影响.结果表明:所采用的工艺条件是合适的,制备的***.4B2O3.12h2O硼酸钾钙复盐晶型发育良好、形貌规整.反应温度的不同会使硼酸钾钙复盐的形貌发生改变.

关键词：硼酸钾钙复盐(K2O.CaO.4B2O3.12h2O) 晶体制备水溶液法表征反应温度

Design of a variable frequency comb reflectometer system for the ASDEX Upgrade tokamak

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Plasma Science and Technology 2020年第6期22卷 8-14页

作者： T hAPPEL W KASPAREK P hENNEQUIN K hÖFLer C hONORÉ the ASDEX Upgrade Team Max-Planck-Institut für Plasmaphysik Boltzmannstr.285748 GarchingGermany IGVP Universität StuttgartPfaffenwaldring 3170569 StuttgartGermany Laboratoire de Physique des Plasmas CNRSÉcole PolytechniqueSorbonne UniversitéF-91120 PalaiseauFrance Physik-Department E28 Technische Universität MünchenJames-Franck-Str.185748 GarchingGermany 不详

Comb reflectometers offer the advantage of measuring several radial positions in plasma *** allows for the investigation of fast timescales during L-h transitions,I-phases,I-mode bursts,transients during heat wave propagation,etc.A drawback of many present-day systems is that they use a fixed frequency difference between the probing ***,although the central probing frequency can be varied,the probing frequency difference is usually *** new design presented in this work uses an advanced microwave generation and detection scheme,which allows for arbitrary probing frequencies and probing frequency separations.

关键词： reflectometry microwaves plasma diagnostic reflectometer turbulence

Fuzzy Stability of the Orthogonal Cauchy Functional equations

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Chinese Quarterly Journal of Mathematics 2018年第3期33卷 302-312页

作者： bi Lv-qing DAI Song-song hU BO School of Electronics and Communication Engineering Guangxi Colleges and Universities KeyLaboratory of Complex System Optimization and Big Data Processing Yulin Normal UniversityYulin537000P.R.China. School of Information Science and Engineering Xiamen UniversityXiamen 361005P.R.China. School of Mechanical and Electrical Engineering Guizhou Normal UniversityGuiyang 550025P.R.China.

In this paper, we establish fuzzy stability of the orthogonal Cauchy functional equations f(x + y) = f(x) + f(y), x ⊥ y and the orthogonal Cauchy functional of P exider type f(x + y) = g(x) + h(y), x ⊥ y in which ⊥... 详细信息

关键词： Fuzzy normed space hyers-Ulam stability Orthogonally Cauchy functionalequation Orthogonally Cauchy functional Pexider equation Orthogonality space

Flow turbulence presented by different vegetation spacing sizes within a submerged vegetation patch

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Journal of hydrodynamics 2023年第6期35卷 1131-1145页

作者： Chukwuemeka Kingsley John Jaan h.Pu Yakun Guo Prashanth R.hanmaiahgari Manish Pandey Faculty of Engineering and Informatics University of BradfordBradfordUK Department of Civil Engineering Indian Institute of TechnologyKharagpurIndia National Institute of Technology(NIT) WarangalIndia

This study presents results from a vegetation-induced flow experimental study which investigates 3-D turbulence structure profiles,including Reynolds stress,turbulence intensity and bursting analysis of open channel *** vegetation densities have been built between the adjacent vegetations,and the flow measurements are taken using acoustic Doppler velocimeter(ADV)at the locations within and downstream of the vegetation *** different tests are conducted,where the first test has compact vegetations,while the second and the third tests have open spaces created by one and two empty vegetation slots within the vegetated *** reveals that over 10%of eddies size is generated within the vegetated zone of compact vegetations as compared with the fewer *** turbulence structures variation is also observed at the points in the non-vegetated *** findings from burst-cycle analysis show that the sweep and outward interaction events are dominant,where they further increase away from the *** effect of vegetation on the turbulent burst cycle is mostly obvious up to approximately two-third of vegetation height where this phenomenon is also observed for most other turbulent structure.

关键词： Velocity profiles acoustic Doppler velocimeter(ADV) turbulent intensities Reynolds stress turbulent bursting vegetated flow vegetation spacing sizes

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不饱和脂肪酸结构与自动氧化关系的理论研究

皮革科学与工程 2009年第4期19卷 5-9页

作者：张文华石碧四川大学制革清洁技术国家工程实验室四川成都610065

利用计算化学B3LYP/6-31G(d,p)方法,以C—h键解离能(BDES)为理论参数,从分子水平研究了影响油脂氧化稳定性的结构因素。以皮革加脂剂中常含的不饱和脂肪酸棕榈油酸(9Z-,16∶1)、油酸(9Z-,18∶1)、蓖麻油酸(9Z-,18∶1)、芥酸(13Z-,22∶1... 详细信息

利用计算化学B3LYP/6-31G(d,p)方法,以C—h键解离能(BDES)为理论参数,从分子水平研究了影响油脂氧化稳定性的结构因素。以皮革加脂剂中常含的不饱和脂肪酸棕榈油酸(9Z-,16∶1)、油酸(9Z-,18∶1)、蓖麻油酸(9Z-,18∶1)、芥酸(13Z-,22∶1)、亚油酸(9Z,12Z-,18∶2)、亚麻油酸(9Z,12Z,15Z-,18∶2)、α-桐油酸(9Z,11E,13E-,18∶3)和二十二碳六烯酸DhA(4Z,7Z,10Z,13Z,156,19Z-,22∶6)为模型,研究了不饱和脂肪酸碳链上最容易发生抽氢反应的位置,以及碳链长度、双键个数、酯化反应、取代基对不饱和脂肪酸自动氧化的影响。计算表明,紧邻不饱和脂肪酸双键(—C=C—)的α—Ch2,尤其是具有双烯丙基结构的α—Ch,是油脂氧化抽氢的位点,而双键上的—Ch=Ch—最难发生抽氢。不饱和脂肪酸的氧化稳定性不仅与双键数目有关,而且与双键的相对位置有关,在抽氢后能形成共轭结构的不饱和脂肪酸容易发生自动氧化。碳链上的取代基对不饱和脂肪酸的自动氧化有影响,吸电子基团有利于提高脂肪酸的氧化稳定性,但碳链的长短对氧化稳定性的影响并没有规律。

关键词：不饱和脂肪酸加脂剂自动氧化计算化学

Simulation of foamed concrete compressive strength prediction using adaptive neuro-fuzzy inference system optimized by nature-inspired algorithms

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 61-79页

作者： Ahmad ShARAFATI h.NADerPOUR Sinan Q.SALIh E.ONYARI Zaher Mundher YASEEN Department of Civil Engineering Science and Research BranchIslamic Azad UniversityTehranIran Faculty of Civil Engineering Semnan UniversitySemnan ***Iran Computer Science Department Dijlah University CollegeBaghdadIraq Department of Civil and Chemical Engineering College of ScienceEngineering and TechnologyUniversity of South AfricaJohannesburgSouth Africa Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam

Concrete compressive strength prediction is an essential process for material design and *** study investigates several novel hybrid adaptive neuro-fuzzy inference system(ANFIS)evolutionary models,i.e.,ANFIS-particle swarm optimization(PSO),ANFIS-ant colony,ANFIS-differential evolution(DE),and ANFIS-genetic algorithm to predict the foamed concrete compressive *** concrete properties,including cement content(C),oven dry density(O),water-to-binder ratio(W),and foamed volume(F)are used as input variables.A relevant data set is obtained from open-access published experimental investigations and used to build predictive *** performance of the proposed predictive models is evaluated based on the mean performance(MP),which is the mean value of several statistical error *** optimize each predictive model and its input variables,univariate(C,O,W,and F),bivariate(C-O,C-W,C-F,O-W,O-F,and W-F),trivariate(C-O-W,C-W-F,O-W-F),and four-variate(C-O-W-F)combinations of input variables are constructed for each *** results indicate that the best predictions obtained using the univariate,bivariate,trivariate,and four-variate models are ANFIS-DE-(O)(MP=0.96),ANFIS-PSO-(C-O)(MP=0.88),ANFIS-DE-(O-W-F)(MP=0.94),and ANFIS-PSO-(C-O-W-F)(MP=0.89),***-PSO-(C-O)yielded the best accurate prediction of compressive strength with an MP value of 0.96.

关键词： foamed concrete adaptive neuro fuzzy inference system nature-inspired algorithms prediction of compressive strength