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Fe_(m)B_(20)(m=1,2)团簇中超快自旋动力学的第一性原理研究

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物理学报 2021年第12期70卷 276-287页

作者：卢欣谢孟琳刘景金蔚李春 Georgios Lefkidis wolfgang hübner 陕西师范大学物理学与信息技术学院西安710119 北京航空航天大学物理学院北京100191 德国凯泽斯劳滕工业大学物理系 OPTIMAS研究中心凯泽斯劳滕676534 西北工业大学力学与土木建筑学院西安710072

利用量子化学第一性原理计算,对FeB_(20)和Fe_(2)B_(20)团簇的几何构型、电子结构以及由激光诱导的超快自旋动力学进行了研究.计算结果发现,Fe B20团簇中Fe原子倾向吸附于B20管内,而Fe_(2)B_(20)团簇的两个Fe原子分居管内外时更稳定.后... 详细信息

利用量子化学第一性原理计算,对FeB_(20)和Fe_(2)B_(20)团簇的几何构型、电子结构以及由激光诱导的超快自旋动力学进行了研究.计算结果发现,Fe B20团簇中Fe原子倾向吸附于B20管内,而Fe_(2)B_(20)团簇的两个Fe原子分居管内外时更稳定.后者由于磁原子个数的增多,引入了更多的d电子态而表现出结构整体能级的下移;同时,由于该结构两磁原子吸附环境的不同,使得其能态具有不同自旋局域的可能性.基于体系所得多体电子基态和激发态,在特定激光脉冲诱导下,在两个团簇上均实现了亚皮秒时间尺度内的超快自旋翻转和自旋交叉两种动力学过程.其中前者均可逆,且保真度都高达89.7%及以上,后者保真度略低,均在78%及以下.另外,在Fe_(2)B_(20)团簇上,实现了两个Fe原子之间的超快自旋转移动力学,其所需激光能量由于初末态较大的能级差和较多的中间态参与而较之其他动力学最高.本文工作为吸附磁原子的管状硼团簇体系上所实现的超快自旋动力学功能进行了预测,可望对其未来的实验实现以及相关自旋逻辑功能器件的设计和应用提供理论指导.

关键词：超快自旋动力学磁性硼团簇第一性原理计算

Escherichia coli challenge and one type of smectite alter intestinal barrier of pigs

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Journal of Animal Science and Biotechnology 2014年第2期5卷 173-180页

作者： Juliana Abranches Soares Almeida Yanhong Liu Minho Song Jeong Jae Lee h Rex Gaskins Carol wolfgang Maddox Orlando Osuna James Eugene Pettigrew Department of Animal Sciences University of IllinoisUrbana 61801USA Department of Animal Science and Biotechnology Chungnam National UniversityDaejeonSouth Korea Department of Pathobiology University of IllinoisUrbana 61801 USA Milwhite Inc.BrownsvilleTXUSA

An experiment was conducted to determine how an E. coil challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs （initial BW： 6.9 ± 1.0 kg） were distributed in a 2 x 4 factorial arrangement of a randomized complete block design （2 challenge treatments： sham or E. coil, and 4 dietary treatments： control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite）, with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays （smectite A） tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it.

关键词： Barrier function E.coli Pigs Smectite Zeolite

大型X射线光学仪器:单层镜和多层镜的制造与表征(英文)

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光学精密工程 2007年第12期15卷 1869-1877页

作者： Michael Strmer Dietrich huβler wolfgang Jger Rüdiger Bormann Institute of Materials Research GKSS-Research Centre Geesthacht GmbHMax-Planck-Strasse 121502 GeesthachtGermany Microanalysis of Materials Faculty of EngineeringUniversity KielKaiserstrasse 224143 KielGermany

150 ～500 mm长度的各种X射线光学元件可用于光束导引,光束调整,以及单色化。本文介绍了两种不同的大型X射线反射镜。第一种为单层反射镜,这种反射镜以2°掠入射角在软X射线区(50 ～200 eV)起全反射镜作用,可用于自由电子激光器,如德国... 详细信息

150 ～500 mm长度的各种X射线光学元件可用于光束导引,光束调整,以及单色化。本文介绍了两种不同的大型X射线反射镜。第一种为单层反射镜,这种反射镜以2°掠入射角在软X射线区(50 ～200 eV)起全反射镜作用,可用于自由电子激光器,如德国汉堡的FLASh。第二种是多层镜,由于它的布喇格反射特性,适于作为反射镜以0 .4 ～1°的入射角用于硬X射线区(20 ～50 keV) ,如层析光束线的同步辐射存储环中。两种反射镜都用最新物理汽相淀积法制备,并用磁控溅射来实现X射线光学应用所需要的优良光学品质。这一淀积工艺使不同批次的镀膜稳定性良好,有利于实际反射镜在优质衬底上的最后淀积。单层镜和多层镜在它们的相关能量范围内都有很高的反射率,表面粗糙度也很低,且在整个光学波长区这些特性表现均匀。文中所叙相关研究都是借助X射线反射计量(XRR)法,透射电子显微镜(TEM)、光学轮廓仪(OP) ,以及原子力显微镜(AFM)完成的。

关键词： X射线光学多层膜反射镜全反射镜 X射线反射测量磁控溅射同步辐射自由电子激光器

Effects of Saccharomyces cerevisiae or boulardii yeasts on acute stress induced intestinal dysmotility

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World Journal of Gastroenterology 2016年第48期22卷 10532-10544页

作者： Christine West Andrew M Stanisz Annette Wong wolfgang A Kunze McMaster Brain-Body Institute St. Joseph’s Healthcare Department of Biology McM aster University Department of Psychiatry and Behavioural Neurosciences Mc Master University

AIM To investigate the capacity of Saccharomyces cerevisiae(S. cerevisiae) and Saccharomyces boulardii(S. boulardii) yeasts to reverse or to treat acute stress-related intestinal *** Adult Swiss Webster mice were stressed for 1 h in a wire-mesh restraint to induce symptoms of intestinal dysmotility and were subsequently killed by cervical dislocation. Jejunal and colon tissue were excised and placed within a tissue perfusion bath in which S. cerevisiae, S. boulardii, or their supernatants were administered into the lumen. Video recordings of contractility and gut diameter changes were converted to spatiotemporal maps and the velocity, frequency, and amplitude of propagating contractile clusters(PCC) were measured. Motility pre- and post-treatment was compared between stressed animals and unstressed controls. RESULTS S. boulardii and S. cerevisiae helped to mediate the effects of stress on the small and large intestine. Restraint stress reduced jejunal transit velocity(mm/s)from 2.635 ± 0.316 to 1.644 ± 0.238, P hz) from 0.032 ± 0.008 to 0.016 ± 0.005, P helped to restore jejunal and colonic velocity towards the unstressed controls; 1.833 ± 0.688 to 2.627 ± 0.664, P had therapeutic effects on the stressed gut, but was most apparent in the jejunum. S. cerevisiae increased PCC velocity in the stressed jejunum from 1.763 ± 0.397 to 2.017 ± 0.48, P = 0.0031 and PCC frequency from 0.016 ± 0.009 to 0.027 ± 0.007, P helped to restore motility to unstressed values in similar capacity. CONCLUSION The

关键词： Intestine Saccharomyces cerevisiae Saccharomyces boulardii Restraint stress Motility

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植物育种模拟的原理和应用

中国农业科学 2007年第1期40卷 1-12页

作者：王建康 wolfgang h.Pfeiffer 中国农业科学院作物科学研究所国家农作物基因资源与基因改良重大科学工程CIMMYT中国办事处国际热带农业研究中心

传统植物育种很大程度上依赖于表型选择和育种家的经验,分子生物学积累的大量遗传数据使得在基因水平上进行目标性状的选择成为可能,但是由于缺乏必要的工具,大量的遗传信息尚未在育种中得以有效利用。模拟方法可以利用各类遗传信息,在... 详细信息

传统植物育种很大程度上依赖于表型选择和育种家的经验,分子生物学积累的大量遗传数据使得在基因水平上进行目标性状的选择成为可能,但是由于缺乏必要的工具,大量的遗传信息尚未在育种中得以有效利用。模拟方法可以利用各类遗传信息,在育种家进行田间试验之前,对杂交组合的表现、后代选择效果以及整个育种过程进行模拟,提出最佳的亲本选配、杂交和后代选择策略,从而提高常规育种的预见性和效率。本文介绍育种模拟的一些基本原理,包括遗传模型的构建、杂交类型和选择方法的定义等,概述育种模拟工具QuLine的基本功能及其在育种方法的比较、利用已知基因信息的亲本选配和设计育种等方面的应用。模拟方法通过定义复杂的遗传模型和育种方法实现对育种过程的模拟,在更真实的情形下比较不同育种方法的优劣、预测不同亲本杂交后代的表现,从而为育种家有效利用大量的分子信息和遗传数据提供了手段。

关键词：育种模拟遗传模型育种策略设计育种综述

Crystal growth of Gd_2PdSi_3 intermetallic compound

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Transactions of Nonferrous Metals Society of China 2014年第1期24卷 115-119页

作者：徐义库 wolfgang LSER 郭亚杰赵新宝刘林长安大学材料科学与工程学院西安710064 德国莱布尼兹固态及材料科学研究所固态材料研究所德累斯顿01171 西北工业大学凝固技术国家重点实验室西安710072

Gd2PdSi3 single crystals were grown by a vertical floating zone method with radiation heating at a zone traveling rate of 3 mm/h. The compound exhibited congruent melting behavior at a liquidus temperature of about 1700 ＆#176;C. The slightly Pd-depleted composition of the crystal, with respect to the nominal Gd2PdSi3 stoichiometry, led to gradual accumulation of Pd in the traveling zone and to a decreasing operating temperature during the growth process. Thin platelet-like precipitates of a GdSi phase were detected in the stoichiometric feed rod growth crystal matrix which can be reduced by annealing treatment. Feed rod composition shift crystal growth was proved to be a better way of getting high quality of Gd2PdSi3 single crystal.

关键词： floating zone technique single crystal growth rare earth compounds precipitates

Kinetically Controlled Supramolecular Block Copolymer Self-Assembly:Multicolor Photonic Crystal Patterns from a Single Formulation

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CCS Chemistry 2023年第10期5卷 2301-2311页

作者： Shuai Deng Renhua Deng Xi Mao Bijin Xiong Mian Wang Senbin Chen wolfgang h.Binder Jintao Zhu Zhenzhong Yang State Key Laboratory of Materials Processing and Die&Mould Technology Key Laboratory of Materials Chemistry for Energy Conversion and Storage(Ministry of Education)School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074 Chair of Macromolecular Chemistry Faculty of Natural Science II(ChemistryPhysicsand Mathematics)Martin Luther University Halle-WittenbergHalle(Saale) Department of Chemical Engineering Tsinghua UniversityBeijing 100084

Photonic crystal(PC)patterns with tunable and changeable nonvolatile structural colors printed from a single ink are of great interest for optical products but have rarely been reported because most inks can only output one respective structural ***,we propose a facile yet effective kinetically controlled self-assembly strategy to address this *** ink formulation containing supramolecular block copolymers(SBCPs)is *** patterns were printed by direct-ink-writing followed by solvent annealing to generate different structural colors by simply controlling the annealing *** self-assembly kinetic regime suggests that different colors result from various kinetically trapped metastable *** turn,the variation in structural color enables“visualization”of the self-assembly ***,we demonstrate that these kinetically trapped structures exhibit different responsive color-change *** addition,this kinetic control strategy can be synergistic with thermodynamic control to extend the color *** study provides a facile yet effective solution for well-designed PC patterns with tunable,responsive,and unfading colors printed from the simplest single-nozzle printer with a single colorless ink,presenting great potential in broad applications,including information storage,encryption,and anti-fake.

关键词： block copolymers self-assembly supramolecules photonic crystals direct write printing kinetics

Promoting effect of nitrogen doping on carbon nanotube-supported RuO2 applied in the electrocatalytic oxygen evolution reaction

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Journal of Energy Chemistry 2016年第2期25卷 280-286页

作者： Kunpeng Xie Wei Xia Justus Masa Fengkai Yang Philipp Weide wolfgang Schuhmann Martin Muhler Laboratory of Industrial Chemistry Ruhr-University Bochum 44780 Bochum Germany Analytical Chemistry-Center for Electrochemical Sciences (CES) Ruhr-University Bochum 44780 Bochum Germany Competence Centre for Catalysis Chemical Engineering Chalmers University of Technology Gothenburg 41296 Sweden Max Planck Institute for Chemical Energy Conversion 45470 Miilheiman der Ruhr Germany

RuO2 nanoparticles supported on multi-walled carbon nanotubes（CNTs） functionalized with oxygen（OCNTs） and nitrogen（NCNTs） were employed for the oxygen evolution reaction（OER） in 0.1 M *** catalysts were synthesized by metal-organic chemical vapor deposition using ruthenium carbonyl（Ru3（CO）（12）） as Ru precursor. The obtained RuO2/OCNT and RuO2/NCNT composites were characterized using TEM, h2-TPR, XRD and XPS in order probe structure–activity correlations, particularly, the effect of the different surface functional groups on the electrochemical OER performance. The electrocatalytic activity and stability of the catalysts with mean RuO2 particle sizes of 13–14 nm was evaluated by linear sweep voltammetry, cyclic voltammetry, and chronopotentiometry, showing that the generation of nitrogen-containing functional groups on CNTs was beneficial for both OER activity and stability. In the presence of RuO2, carbon corrosion was found to be significantly less severe.

关键词： Ruthenium dioxide Chemical vapor deposition Nitrogen-doped carbon nanotubes Oxygen evolution reaction

Differentiation of human mesenchymal stem cell spheroids under microgravity conditions

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Cell Regeneration 2012年第1期1卷 2-10页

作者： wolfgang h Cerwinka Starlette M Sharp Barbara D Boyan haiyen E Zhau Leland W K Chung Clayton Yates Children’s healthcare of Atlanta Emory University School of Medicine5445Meridian Mark RoadSuite 420AtlantaGA 30342USA Department of Biology and Center for Cancer Research Tuskegee UniversityCarver Research BuildingTuskegee InstituteAL 36088USA The Wallace h.Coulter Department of Biomedical Engineering Georgia Institute of Technology313 Ferst Drive AtlantaAtlantaGA 30332USA Samuel-Oschin Comprehensive Cancer Institute Cedars-Sinai Medical Center8750 Beverly Blvd.Atrium 103Los AngelesCA 90048USA Georgia Pediatric Urology 5445 Meridian Mark RdSuite 420AtlantaGA 30342USA Tuskegee University Carver Research Bld.Rm 22TuskegeeAL 36088USA.

To develop and characterize a novel cell culture method for the generation of undifferentiated and differentiated human mesenchymal stem cell 3D structures,we utilized the RWV system with a gelatin-based scaffold.3×10^(6) cells generated homogeneous spheroids and maximum spheroid loading was accomplished after 3 days of *** cultured in undifferentiated spheroids of 3 and 10 days retained expression of CD44,without expression of differentiation *** cultured in adipogenic and osteogenic differentiation media exhibited oil red O staining and von Kossa staining,*** characterization of osteogenic lineage,showed that 10 day spheroids exhibited stronger calcification than any other experimental group corresponding with significant expression of vitamin D receptor,alkaline phosphatase,and *** conclusion this study describes a novel RWV culture method that allowed efficacious engineering of undifferentiated human mesenchymal stem cell spheroids and rapid osteogenic *** use of gelatin scaffolds holds promise to design implantable stem cell tissue of various sizes and shapes for future regenerative treatment.

关键词： Mesenchymal stem cell RWV culture Tissue engineering Differentiation Osteogenesis