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Studies on sensitivity to tension and gating pathway of MscL by molecular dynamic simulation

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Acta Mechanica Sinica 2013年第2期29卷 256-266页

作者： Jun-Yu xie guang-Hong Ding Mechanics and Engineering Science Fudan University Shanghai Research Center of Acupuncture and Maridians

Mechanosensitive（MS） ion channels play an important role in various physiological *** the determination of the structure of mechanosensitive channel of large conductance（MscL） makes the simulation study possible,it has not so far been possible to directly simulate the gating mechanism of MscL in atomic *** this article,MscL has been studied via molecular dynamic（MD） simulations to gain a detailed description of the sensitivity to lateral tension and the gating *** undergoes conformational rearrangement in sustaining lateral tension,and the open state is obtained when 2.0 MPa lateral tension is directly applied on the pure *** the opening process,Loop region responds to tension first,and the mechanical sensitivity is followed by S1 ***（TM） bundle is the key position for channel opening,and the motion of TM1 helices finally realizes the significant expansion of the constricted gating pore.C-terminus domain presents expansion later during the TM *** our study,return of the whole protein to the initial closed state is achieved only in the early opening *** the relaxation from the open state,the TM helices are the most mobile domain,which is different from the opening process.

关键词： Molecular dynamic simulation·MscL·Lateral tension·Sensitivity·Gating pathway

A Periodicity Analysis of the Light Curve of 3C 454.3

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 421-429页

作者： Huai-Zhen Li guang-Zhong xie shu-Bai Zhou Hong-Tao Liu guang-Wei Cha Li Ma Li-Sheng Mao National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049 Yunnan Astronomical Center Yunnan University Kunming 650091 Physics Department Yunnan University Kunming 650091 Physics Department Yunnan Normal College Kunming 650091

We analyzed the radio light curves of 3C 454.3 at frequencies 22 and 37 GHz taken from the database of Metsaeovi Radio Observatory, and found evidence of quasi-periodic activity. The light curves show great activity with very complicated non-sinusoidal variations. Two possible periods, a very weak one of 1.57 ± 0.12 yr and a very strong one of 6.15 ±0.50 yr were consistently identified by two methods, the Jurkevich method and power specmun estimation. The period of 6.15 ± 0.50 yr is consistent with results previously reported by Ciaramella et al. and Webb et al. Applying the binary black hole model to the central structure we found black hole masses of 1.53 × 10^9M⊙ and 1.86 × 10^8M⊙, and predicted that the next radio outburst is to take place in 2006 March and April.

关键词： galaxies: individual (3C 454.3)-- galaxies: fundamental parameters-- methods:data analysis

Dual-steering mode based on direct yaw moment control for multi-wheel hub motor driven vehicles:Theoretical design and experimental assessment

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Defence Technology（防务技术） 2022年第1期18卷 49-61页

作者： Zheng Zhang Xiao-jun Ma Chun-guang Liu shu-guang Wei Department of Weapons and Control Engineering Army Academy of Armored ForcesBeijing100072China

One of the main challenges for multi-wheel hub motor driven vehicles is the coordination of individual drivetrains to improve mobility and stability in the steering *** paper proposes a dual-steering mode based on direct yaw moment control for enhancing vehicle steering ability in complex environ *** control system is designed as a hierarchical structure,with a yaw moment decision layer and a driving force distribution *** the higher-level layer,the objective optimization function is con-structed to obtain the slip steering ratio,which represents the degree of vehicle slip steering in the dual-steering *** moment controller using active disturbance rejection control theory is designed for continuous yaw rate *** the actual yaw rate of the vehicle deviates from the reference yaw rate obtained by the vehicle reference model and the slip steering ratio,the yaw moment controller isactuated to determine the yaw moment demand for vehicle *** the lower-level layer,there is a torque distribution controller based on distribution rules,which meets the requirement of yaw moment demand without affecting the total longitudinal driving force of the *** verifying the validity and feasibility of the dual-steering mode,simulations were conducted on the hardware-in-loop real-time simulation ***,corresponding real vehicle tests were carried out on an eight-wheel prototype *** results were generally consistent with the simulation results,thereby demon-strating that the proposed dual-steering mode reduces steering radius and enhances the steering per-formance of the vehicle.

关键词： Multi-wheel hub motor driven vehide Dual-steering mode Direct ya w moment control Real-time simulation

Effects of High-Power Ultrasonic Treatment on the Slurryability of Coals

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Journal of China University of Mining and Technology 2007年第4期17卷 562-565页

作者： CUI guang-wen ZHU shu-quan ZOU Li-zhuang xie Wei-wei School of Chemical and Environmental Engineering China University of Mining ＆ Technology Beijing 100083 China School of Chemical and Environmental Engineering Shandong University of Science and Technology Qingdao Shandong 266510 China

To improve slurryability,high power ultrasonic energy was used to treat coal slurry. The influence of power on the slurryability of raw coals and on the maximum hydro-content (MHC) was investigated by measuring the apparent viscosity before and after treatment. The experimental results show that the effect of treatment on sluryability is different for different rank coals under the same treatment conditions. The coals metamorphosed to lower degree are more sensitive to the ultrasonic treatment. The apparent viscosity of slurries from coal metamorphosed to medium degree clearly decreases after the ultrasonic treatment. The ultrasonic treatment makes MHC decrease,which improves the slurryability. For Shenmu or Hebi coal slurry after 3 min. treatment the maximum fixed-viscosity concentration is increased by about 0.4% and 0.3%,respectively,when the ultrasonic power is 100 W. The maximum fixed-viscosity concentration increased 2.4% and 1.7%,respectively,when the ultrasonic power was 300 W,but it decreased by about 0.4% and 0.7%,respectively,when the power was 500 W.

关键词： water slurry slurryability ultrasonic wave viscosity

Invasive Spartina alterniflora-induced factors affecting epibenthos distribution in coastal salt marsh, China

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Acta Oceanologica Sinica 2013年第2期32卷 81-88页

作者： xie Wenjing GAO shu School of Geographic and Oceanographic Sciences Nanjing University Key Laboratory of Coast and Island Development of Ministry of Education Nanjing University

Artificially introduced cordgrass, Spartina alterniflora, rapidly colonized the intertidal flats of the Jiangsu coast, eastern China. The epibenthos on an intertidal flat invaded by S. alterniflorawere studied, to identify how local epibenthos species react to an altered environment. Epibenthic samples and surficial sediment samples were collected along a shore-normal profile in 50 quadrats at ten stations across the Spartina salt marsh; and five control quadrats for a station located on the barren sandy-mud flat. The grain size param- eters of the surficial sediments show that S. alterniflora altered the grain size gradient along the profile of the intertidal zone by trapping fine-grained sediments. Spartina alterniflora could inhabit lower elevation- s than indigenous salt marsh vegetation, thus creating larger areas of finer surficial sediments, which was suitable for not only native epibenthic species but also species which do not exist on the barren sandy-mud flat. Correlation analyses show that the epibenthos were sensitive to sediment grain size and type, on the invaded S. alterniflora salt marsh. Further, there was an interspecific relationship affecting the distribution of epibenthos. The results show that epibenthos preferred ecological niches, within the Spartina salt marsh, even in the same sampling station.

关键词： benthos ecology exotic plant species grain size tidal-flat sedimentation Jiangsu coast

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洁净手术部浮游菌浓度动态监测结果分析

中国消毒学杂志 2017年第4期34卷 321-324页

作者：高兴莲熊莉娟谢曙光苏法安戴頔王曾妍余文静李婷婷华中科技大学同济医学院附属协和医院湖北武汉430022 湖北省疾病预防控制中心

目的用六级空气撞击式采样器对Ⅴ~Ⅶ级洁净手术间空气中的浮游菌采样,监测动态下浮游菌浓度。方法随机抽样在Ⅴ~Ⅶ级洁净手术间内实施的63例患者,采用空气撞击法采取样品,采样空气量为28.3 L/min,采样时间为30 min,分别对静态下、手术60... 详细信息

目的用六级空气撞击式采样器对Ⅴ~Ⅶ级洁净手术间空气中的浮游菌采样,监测动态下浮游菌浓度。方法随机抽样在Ⅴ~Ⅶ级洁净手术间内实施的63例患者,采用空气撞击法采取样品,采样空气量为28.3 L/min,采样时间为30 min,分别对静态下、手术60 min时、手术结束时三个时间段手术间浮游菌浓度进行监测;术后随访1个月,观察手术部位感染情况。结果静态下浮游菌浓度监测结果在国标范围内,P﹥0.05,无统计学意义;手术60 min时和手术结束时动态浮游菌监测结果变化幅度大,且手术60 min时浮游菌浓度大于手术结束时。动态监测结果显示:Ⅴ~Ⅶ级手术间手术区均值为(8.40±9.94)cfu/m^3,(35.41±36.88)cfu/m^3,(59.38±29.69)cfu/m^3,周边区均值为(16.60±17.02)cfu/m^3、(61.28±72.83)cfu/m^3和(96.62±61.47)cfu/m^3。其中90%为腾黄微球菌,10%为白色微球菌。术后随访未发生手术部位感染。结论洁净手术间浮游菌动态监测浓度变化大,幅度在20~185 cfu/m^3,但采样结果能表达理论模型下手术间空气洁净度分区。

关键词：撞击法空气采样浮游菌动态监测手术间洁净度

Alpha-Chain Structure of ^(12)C

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Chinese Physics Letters 1996年第7期13卷 516-519页

作者： xie Wen-fang BAO Cheng-guang Department of Physics Guangdong University of TechnologyGuangzhou 510090 CCAST(World Laboratory)P.O.Box 8730Beijing 100080 Department of Physics Zhongshan UniversityGuangzhou 510275

Alpha-chain states in ^(12)C are studied via an analysis of underlying quantum mechanical *** is pointed out that the linear chain band exists undoubting in ^(12)***,the pure linear chain structure does not exist in ^... 详细信息

关键词： symmetry triangle

湖北省16家省直管医院手术室环境卫生质量检测结果分析

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维普期刊数据库

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公共卫生与预防医学 2011年第4期22卷 26-29页

作者：谢曙光吴培华陈俐侃陈如程燕虹唐利军湖北省疾病预防控制中心武汉430079 武汉大学公共卫生学院

目的了解湖北省直管医院手术室的环境卫生质量,系统评估省直管医院洁净手术室及普通手术室的院感管理水平,为制定相应的卫生标准提供依据。方法按《医院洁净手术部建筑技术规范》和《医院消毒卫生标准》对湖北省直管的16家医院的106间... 详细信息

目的了解湖北省直管医院手术室的环境卫生质量,系统评估省直管医院洁净手术室及普通手术室的院感管理水平,为制定相应的卫生标准提供依据。方法按《医院洁净手术部建筑技术规范》和《医院消毒卫生标准》对湖北省直管的16家医院的106间手术室环境卫生质量进行检测。结果 106间手术室合格率为85.85%,Ⅰ、Ⅱ、Ⅲ、Ⅳ级洁净手术室和普通手术室的合格率分别为68.75%、94.12%、91.80%、71.43%和60.00%;空气中尘粒数与浮游菌浓度具有相关性;普通手术室沉降菌和紫外线强度合格率分别为80%和60%,洁净手术室的截面平均风速、换气次数、相对湿度的合格率均为100%,温度、噪声、照度和静压差的合格率分别为97.03%、97.03%、94.94%和93.07%。结论省直管医院手术室的合格率较低,应加强医院手术室新建设计的审查、日常维护及定期检测,提高医院手术室管理水平。

关键词：手术室环境卫生质量检测

Controlled synthesis and optical properties of Ce^(3+)/Tb^(3+) co-doped BaGdF_5 nanocrystals

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Rare Metals 2015年第9期34卷 673-678页

作者： Chun-Yan Cao An xie Xiao-guang Yu College of Mathematics and Physics Jinggangshan University School of Materials Science and Engineering Xiamen University of Technology

Based on a hydrothermal method, the Ce3+/Tb3+ co-doped Ba Gd F5 nanocrystals were synthesized by controlling the introduction concentration of Ba2+ and Gd3+. The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM) images, photoluminescence(PL) excitation, and emission spectra, as well as the photoluminescence dynamic decay curves. With the increase of the Ba2+ concentration in the synthesis procedure, the positions of diffraction peaks of XRD patterns move toward lower degree, and the case of the samples synthesized with the increase of the Gd3+ concentration is contrary, which consists well with each other. The FE-SEM images suggest that the BaGdF5 nanocrystals are in spherical morphology,and the average diameters decrease with the increase of Ba2+ or Gd3+ concentration. For the 4f–5d transition of Ce3+ is sensitive to the environment of local lattice, the PL excitation and emission spectra of the samples are different. The 4f–4f transition of Tb3+ also presents different optical properties in different host lattices. The variations of the optical properties of Ce3+ and Tb3+ as well as the lifetime of the 5D4+7F5 emission of Tb3+ are also consistent well with each other in the two series of samples.

关键词： Hydrothermal synthesis Optical properties Nanocrys