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磁化天体准直流中非理想效应的实验室研究

物理学报 2020年第19期69卷 142-150页

作者：陶弢中国科学技术大学物理学院工程与应用物理系合肥230000

磁准直是塑造天体外流形貌的重要机制,它的有效性已经在激光等离子体实验中被无量纲验证.本文在现有磁准直射流研究框架的基础上,综合实验与模拟,通过改变激光等离子体烧蚀靶材引入不同冷却和耗散强度,以观察这些非理想效应对准直流形... 详细信息

磁准直是塑造天体外流形貌的重要机制,它的有效性已经在激光等离子体实验中被无量纲验证.本文在现有磁准直射流研究框架的基础上,综合实验与模拟,通过改变激光等离子体烧蚀靶材引入不同冷却和耗散强度,以观察这些非理想效应对准直流形态的影响.使用低原子序数靶时,烧蚀外流和外加强磁场的相互作用满足理想磁流体条件,外流形成了抗磁空腔和沿磁场延展的射流;而采用高原子序数靶时,准直结构被磁扩散破坏,强烈的冷却使得外流停滞,形成与靶面分离的弱准直磁化密度团.无量纲分析表明,磁扩散对实验室等离子体准直形态的破坏,有可能推广解释原恒星射流在大尺度上的消散;而强耗散等离子体展现的弱准直腔与密度堆积,有可能用来类比行星状星云中的弱极化椭球形腔体,以及腔体头部的发光团簇.本文通过考察实验室磁化等离子体演化,支持了非理想效应能够塑造天体外流的理论猜想,对研究非相对论性天体外流形态的形成机制具有重要参考意义.

关键词：天体外流准直射流实验室天体物理磁流体

《绿皮书》与《拉格泰姆时代》:从暴力到隐忍、从孤岛到友谊的文本互涉

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电影评介 2019年第5期 19-23页

作者：陶晓中国人民大学外国语学院杜克大学中美富布赖特

电影《绿皮书》(Green Book,2018)讲述了1962年黑人钢琴家唐纳德?谢尔利(Donald Shirley)前往美国中西部及南方保守地区巡回演出的故事。这是唐纳德?谢尔利在种族隔离尚未废除的美国为争取种族平等而自发参加的勇气之行,以一种更加温和... 详细信息

电影《绿皮书》(Green Book,2018)讲述了1962年黑人钢琴家唐纳德?谢尔利(Donald Shirley)前往美国中西部及南方保守地区巡回演出的故事。这是唐纳德?谢尔利在种族隔离尚未废除的美国为争取种族平等而自发参加的勇气之行,以一种更加温和隐忍的艺术方式继承了《拉格泰姆时代》(Ragtime)中的暴力英雄小科尔豪斯(Coalhouse Walker Jr.)的夙愿。意大利裔美国人托尼?瓦勒隆加(Tony Vallelonga)担任他的临时司机兼保镖。在接下来的八周中,他们遭遇了一系列的种族歧视和不公正待遇,经历了磨合与争吵,开始了解彼此,最终肝胆相照,建立了深厚的友谊。

关键词：《拉格泰姆时代》《绿皮书》文本互涉隐忍暴力友谊孤岛 Green

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超媒体同步模型研究

小型微型计算机系统 2000年第3期21卷 325-328页

作者：李春光温涛抚顺石油学院计算机科学与工程系抚顺113001

本文以 Dexter超文本参考模型为标准 ,吸收了 Am sterdam超媒体模型和 Trellis模型的优点 ,将所提出的分布多媒体同步 Petri网模型 ( DMSPN)扩展到超媒体 ,即提出一种分布超媒体同步 Petri网模型 ( DHSPN) .该模型可较好地解决分布超媒... 详细信息

本文以 Dexter超文本参考模型为标准 ,吸收了 Am sterdam超媒体模型和 Trellis模型的优点 ,将所提出的分布多媒体同步 Petri网模型 ( DMSPN)扩展到超媒体 ,即提出一种分布超媒体同步 Petri网模型 ( DHSPN) .该模型可较好地解决分布超媒体系统中超链、对象同步和用户交互三个关键问题 .

关键词： Petri网同步模型超媒体超文本多媒体

Single Crystal Fibers:Diversified Functional Crystal Material

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Advanced Fiber Materials 2019年第3期1卷 163-187页

作者： tao Wang Jian Zhang Na Zhang Siyuan Wang Baiyi Wu Na Lin Peter Kusalik Zhitai Jia Xutang tao State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100People’s Republic of China Key Laboratory of Functional Crystal Materials and Device Ministry of EducationJinan 250100China Department of Chemistry University of CalgaryCalgaryAB T2N 1N4Canada Key Laboratory of Functional Crystals and Laser Technology TIPCCASBeijing 100190China

Single crystal fibers(SCF)are considered to be a combination of bulk crystals and conventional fibers,thereby possessing the stable physical and chemical properties accompanied with excellent waveguide *** paper gives a detailed introduction to the development history of single crystal fibers,including the evolution of the growth technique and the optimization of the growth ***-heated pedestal growth(LHPG)and Micro-pulling-down(μ-PD)methods are considered to be the most widely used growth techniques for growing single crystal fibers,and the advantages of the two methods are also introduced in *** second part of this paper describes the characterization of single crystal fibers,including diameter fluctuation,crystal quality and optical losses.A series of cladding approaches for SCF,such as magnetron sputtering,sol-gel,liquid phase epitaxy,co-drawing LHPG,ion implantation and micro-structure cladding will be *** addition,the research status of single crystal fiber laser and single crystal fiber sensor are also summarized in view of the current research foundation.

关键词： Single crystal fibers LHPG μ-PD Characterization method Cladding approaches Single crystal fiber laser Single crystal fiber sensor

Effective removal of the protective ligands from Au nanoclusters by ambient pressure nonthermal plasma treatment for CO oxidation

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Chinese Journal of Catalysis 2018年第5期39卷 929-936页

作者： Yuan Tan Hua Liu xiao Yan Liu Aiqin Wang Changjun Liu tao Zhang State Key Laboratory of Catalysis iChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Gold Catalysis Research CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Collaborative Innovation Center of Chemical Science and Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

We used a dielectric barrier discharge(DBD)plasma technique to eliminate the protective ligand of ZnAl-hydrotalcite-supported gold *** used X-ray powder diffraction,ultraviolet-visible spectrophotometry,thermogravimetric analysis,and high angle annular dark-field-scanning transmission electron microscopy characterization to show that the samples pretreated with/without DBD-plasma displayed different performances in CO *** enhanced activity was obtained on the plasma-treated samples,implying that the protective ligand was effectively removed via the plasma *** crystal structure of the plasma-treated samples changed markedly,suggesting that the plasma treatment could not only break the chemical bond between the gold and the protective agent but could also decompose the interlayer ions over the hydrotalcite *** particle sizes of the gold after DBD-plasma treatment implied that it was a good way to control the size of the gold nanoparticles under mild conditions.

关键词： Gold cluster Plasma Supported gold catalyst Protective ligand Carbon monoxide oxidation

Protective effects of ACLF sera on metabolic functions and proliferation of hepatocytes co-cultured with bone marrow MSCs in vitro

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World Journal of Gastroenterology 2011年第19期17卷 2397-2406页

作者： xiao-Lei Shi Jin-Yang Gu Yue Zhang Bing Han Jiang-Qiang xiao Xian-Wen Yuan Ning Zhang Yi-tao Ding Department of Hepatobiliary Surgery the Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing 210008 Jiangsu Province China Jiangsu Provin- cial Key Medical Center for Hepatobiliary Diseases Nanjing 210008 Jiangsu Province China Jiangsu Key Labora- tory of Molecular Medicine Nanjing 210008 Jiangsu Province Jiangsu Province China Institute of Hepa- tobiliary Surgery Nanjing University Nanjing 210008 Jiangsu Province China Department of Hepatobiliary Surgery Drum Tower Clinical Medical College of Nanjing Medical University Nan- jing 210008 Jiangsu Province China Center for Artificial Liver Therapy Nanjing Sec- ond Hospital Naniing 210008 Jiangsu Province China

AIM： To investigate whether the function of hepatocytes co-cultured with bone marrow mesenchymal stem cells （MSCs） could be maintained in serum from acute-on- chronic liver failure （ACLF） ***： Hepatocyte supportive functions and cy- totoxicity of sera from 18 patients with viral hepatitis B-induced ACLF and 18 healthy volunteers were evalu- ated for porcine hepatocytes co-cultured with MSCs and hepatocyte mono-layered culture, respectively. Chemo- kine profile was also examined for the normal serum and liver failure ***： Hepatocyte growth factor （HGF） and Tumor necrosis factor; tumor necrosis factor （TNF）-a were re- markably elevated in response to ACLF while epidermal growth factor （EGF） and VEGF levels were significantly decreased. Liver failure serum samples induced a higher detachment rate, lower viability and decreased liver sup- port functions in the homo-hepatocyte culture. Hepato-cytes co-cultured with MSCs could tolerate the cytotoxic- ity of the serum from ACLF patients and had similar liver support functions compared with the hepatocytes cul- tured with healthy human serum in vitro. In addition, co- cultured hepatocytes maintained a proliferative capability despite of the insult from liver failure ***： ACLF serum does not impair the cell morphology, viability, proliferation and overall metabolic capacities of hepatocyte co-cultured with MSCs in vitro.

关键词： Acute-on-chronic liver failure serum Primary hepatocytes Bone marrow marrow mesenchymal stem cells Co-culture Hepatocyte-based modality

Occurrence modes of silver in the Ni-Mo-PGE polymetallic layer of the Lower Cambrian black shales in Zunyi, Guizhou Province, South China

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Chinese Journal Of Geochemistry 2014年第4期33卷 387-392页

作者： HAN tao ZHU xiaoqing LIU Shirong LI xiaoxia State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The Ni-Mo-PGE polymetallic mineralization of the Lower Cambrian black shales locate in Zunyi, South China and contain abundant noble metals such as Ag, Au and PGE, and especially Ag with average concentration of 64×10-6. The occurrence modes of Ag have been investigated using methods of selective chemical dissolution and transmission electron microscopy. The results demonstrate that the occurrence modes of Ag are complex and diversiform. It might be associated with clay minerals, organic matter, sulfides and also occurred as native silver and sulfides with nanometer in size. Combined with results of previous studies, we suggest that the sulfides, clay minerals and organic matter which hosted in the Ni-Mo-PGE polymetallic ores of black shales can play the roles of important reduction and adsorption geochemical barriers for the enrichment and distribution of silver. This study further implies that the selective chemical dissolution and transmission electron microscopy may pave the way to study the occurrence modes of other noble metals in black shales.

关键词：多金属矿化黑色页岩下寒武统中国南方 PGE 白银镍钼遵义

Synthesis and structure analysis of aluminum doped zinc oxide powders

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Science China Chemistry 2008年第9期51卷 823-828页

作者： NIE DengPan XUE tao ZHANG Yu LI XiangJun Guizhou Institute of Metallurgy and Chemical Engineering Guiyang 550002China School of Chemical Engineering Guizhou UniversityGuiyang 550003China College of Chemistry and Chemistry Engineering Graduate University of Chinese Academy of SciencesBeijing 100049China

Hexagonal Al-doped zinc oxide (ZnO) powders with a nominal composition of Zn1?x Al x O (0?x?0.028) were synthesized by the co-precipitation method. The contents of the Al element in the samples were measured by the inductively coupled plasma-optical emission spectroscopy (ICP-OES) technique. The structures of the Zn1?x Al x O (0?x?0.028) compounds calcined at 1000 and 1200°C have been determined using the Rietveld full-profile analysis method. Rietveld refinements of the diffraction data indicated that the addition of Al initially has a considerably positive effect on the decreasing of the lattice parameters a and c of Zn1?x Al x O, but the effect becomes very slight and even negative with the further increase of the Al content. The solid solubility limit of Al in ZnO (mole fraction y) is 2.2l%, resulting in Zn0.978Al0.22O. It seems that when the Al content is excessive, Al prefers to form a ZnAl2O4 compound with ZnO, but not to incorporate into the ZnO lattice to occupy the Zn2+ cites. Two phases, [ZnO] (or Al-doped ZnO) and [ZnAl2O4], are obviously segregated in Zn1?x Al x O while the value of x is larger than 0.024. The UV-Vis absorption spectra show that the Al-doped ZnO exhibits a red-shift in the absorption edge without reduced transmission compared with pure ZnO, which also confirms that Al ions enter the ZnO lattice and form a Zn1?x Al x O solid solution.

关键词： Al-doped zinc oxide (ZnO) co-precipitation method X-ray diffraction crystal structure

An analytical validation for the attenuation of lateral propagating light in sea ice

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Acta Oceanologica Sinica 2015年第3期34卷 1-8页

作者： ZHAO Jinping LI tao EHN Jens BARBER David Physical Oceanography Laboratory Ocean University of China Centre for Earth Observation Science University of Manitoba

The attenuation of lateral propagating light （LPL） in sea ice was measured using an artificial light source in the Canadian Arctic during the 2007/2008 winter. The apparent attenuation coefficientμ（λ）for lateral prop-agating light was obtained from the measured logarithmic relative variation rate. In this study an analytical solution based on the strict optical theories is developed to validate the measured result. There is a good consistency between theoretical solution and measured data, by which a quite simple but very rigorous relationship among the light source, measurement geometry, and measured irradiance is established. The attenuation coefficients acquired by measurement and theory are the diffusion attenuation as an apparent optical property of ice, independent of the light source and shining condition. The attenuation ability of sea ice should be caused by the microstructure of sea ice, such as crystal size, ice density, brine volume, air inclusion, etc. It also includes the leak from both interfaces by directional scattering. It is verified that the measuring approach is operational and accurate to measure the attenuation of the LPL. The solution from this study did not tell the connection among the extinction and the inclusions of sea ice theoretically be-cause of insufficient understanding.

关键词： Arctic,sea ice lateral propagating light optical attenuation coefficient artificial light analytical solution