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Interaction of aloe-emodin with human serum albumin

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Chinese Science Bulletin 2007年第2期52卷 200-204页

作者： DU jinFeng LI Ying zhang Qi YAO Xiaojun Key Laboratory of Tropical Biological Resources Ministry of Education Hainan Provincial Key Laboratory of Fine Chemicals Hainan University Haikou 570228 China Department of Chemistry Lanzhou University Lanzhou 730000 China

The presence of several high affinity binding sites on human serum albumin (HSA) makes it a possible target for many drugs. This study is designed to examine the effect of aloe-emodin on HSA by fluo-rescence, CD spectroscopy and molecular modeling. The results of fluorescence measurements sug-gested that the hydrophobic interaction was the predominant intermolecular force stabilizing the AE-HSA complex, which was in good agreement with the result of molecular modeling study. And the enthalpy change ΔH0 and the entropy change ΔS0 were calculated to be -7.041 kj·mol-1 and 76.619 j·mol-1·K-1 according to the Van't Hoff equation. The alterations of protein secondary structure in the presence of AE in aqueous solution were quantitatively calculated from CD spectra, and the content of α-helices obviously increased.

关键词：人体细胞精液生殖细胞白蛋白分子模型

Enhanced and tunable fluorescent quantum dots within a single crystal of protein

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Nano Research 2013年第9期6卷 627-634页

作者： Hui Wei Stephen House jiangjiexing Wu jiong zhang Zidong Wang Ying He Elizabeth j. Gao Yigui Gao Howard Robinson Wei Li jianmin Zuo lan M. Robertson Yi Lu Department of Chemistry University of Illinois at Urbana-Champaign Illinois 61801 USA Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Illinois 61801 USA Key Laboratory for Green Chemical TechnologyMOE Tianjin University Tianjin 300072 China George L. Clark X-Ray Facility and 3M Materials Laboratory University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA Department of Biology Brookhaven National Laboratory Upton New York 11973 USA

The design and synthesis of bio-nano hybrid materials can not only provide new materials with novel properties, but also advance our fundamental understanding of interactions between biomolecules and their abiotic counterparts. Here, we report a new approach to achieving such a goal by growing CdS quantum dots （QDs） within single crystals of lysozyme protein. This bio-nano hybrid emitted much stronger red fluorescence than its counterpart without the crystal, and such fluorescence properties could be either enhanced or suppressed by the addition of Ag（I） or Hg（II）, respectively. The three-dimensional incorporation of CdS QDs within the lysozyme crystals was revealed by scanning transmission electron microscopy with electron tomography. More importantl~ since our approach did not disrupt the crystalline nature of the lysozyme crystals, the metal and protein interactions were able to be studied by X-ray crystallography, thus providing insight into the role of Cd（II） in the CdS QDs formation.

关键词： functionalbio-nanomaterials quantum dots protein single crystals X-ray crystallography tomography

Cosmological neutrino simulations at extreme scale

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Research in Astronomy and Astrophysics 2017年第8期17卷 89-100页

作者： j.D.Emberson Hao-Ran Yu Derek Inman Tong-jie zhang Ue-Li Pen joachim Harnois-Deraps Shuo Yuan Huan-Yu Teng Hong-Ming Zhu Xuelei Chen Zhi-Zhong Xing Canadian Institute for Theoretical Astrophysics University of TorontoM5S 3H8ONCanada Department of Astronomy&Astrophysics University of TorontoTorontoON M5S 3H4Canada ALCF Division Argonne National LaboratoryLemontIL 60439USA Kavli Institute for Astronomy&Astrophysics Peking UniversityBeijing 100871China Department of Astronomy Beijing Normal UniversityBeijing 100875China Department of Physics University of TorontoTorontoONtario M5S IA7Canada School of Physics and Electric Information Shandong Provincial Key Laboratory of BiophysicsDezhou UniversityDezhou 253023China Dunlap Institute for Astronomy and Astrophysics University of TorontoTorontoON M5S 3H4Canada Canadian Institute for Advanced Research Program in cosmology and Gravitation Perimeter Institute for Theoretical Physics WaterlooONN2L 2Y5Canada Department of Physics&Astronomy University of British ColumbiaVancouverBC V6T 1Z1Canada Scottish University Physics Alliance Institute for AstronomyUniversity of EdinburghEH93HJScotlandUK Department of Astronomy Peking UniversityBeijing 100871China Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy ofSciencesBeijing 100012China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Constraining neutrino mass remains an elusive challenge in modern *** measurements are expected from several upcoming cosmological probes of large-scale *** this goal relies on an equal level of precision from theoretical predictions of neutrino *** simulations of the non-linear evolution of cold dark matter and neutrinos play a pivotal role in this *** incorporate neutrinos into the cosmological N-body code CUBEP3M and discuss the challenges associated with pushing to the extreme scales demanded by the neutrino *** highlight code optimizations made to exploit modern high performance computing architectures and present a novel method of data compression that reduces the phase-space particle footprint from 24 bytes in single precision to roughly 9 *** scale the neutrino problem to the Tianhe-2 supercomputer and provide details of our production run,named Tian Nu,which uses 86%of the machine(13 824 compute nodes).With a total of 2.97 trillion particles,Tian Nu is currently the world’s largest cosmological N-body simulation and improves upon previous neutrino simulations by two orders of magnitude in *** finish with a discussion of the unanticipated computational challenges that were encountered during the Tian Nu runtime.

关键词： cosmology theory—large-scale structure of universe—methods numerical

RECTANGLE: a bit-slice lightweight block cipher suitable for multiple platforms

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Science China(Information Sciences) 2015年第12期58卷 89-103页

作者： zhang WenTao BAO ZhenZhen LIN DongDai Vincent RIjMEN YANG Bo Han Ingrid VERBAUWHEDE State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences Department of Electrical Engineering ESAT COSIC and i Minds Security Department

In this paper, we propose a new lightweight block cipher named RECTANGLE. The main idea of the design of RECTANGLE is to allow lightweight and fast implementations using bit-slice techniques. RECTANGLE uses an SP-network. The substitution layer consists of 16 4 × 4 S-boxes in parallel. The permutation layer is composed of 3 rotations. As shown in this paper, RECTANGLE offers great performance in both hardware and software environment, which provides enough flexibility for different application scenario. The following are3 main advantages of RECTANGLE. First, RECTANGLE is extremely hardware-friendly. For the 80-bit key version, a one-cycle-per-round parallel implementation only needs 1600 gates for a throughput of 246 Kbits/s at100 k Hz clock and an energy efficiency of 3.0 p j/bit. Second, RECTANGLE achieves a very competitive software speed among the existing lightweight block ciphers due to its bit-slice style. Using 128-bit SSE instructions,a bit-slice implementation of RECTANGLE reaches an average encryption speed of about 3.9 cycles/byte for messages around 3000 bytes. Last but not least, we propose new design criteria for the RECTANGLE *** to our careful selection of the S-box and the asymmetric design of the permutation layer, RECTANGLE achieves a very good security-performance tradeoff. Our extensive and deep security analysis shows that the highest number of rounds that we can attack, is 18(out of 25).

关键词： lightweight cryptography block cipher design bit-slice hardware efficiency software efficiency

Optimization of Quenching Process for ZTAP/ High Chromium Cast Iron Composites

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journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1137-1142页

作者： WEI Hongming jIANG Yehua zhang Xiaozu jIA Yuanwei ZHOU Mojin XUE Da Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

In order to solve the problem of cracking of ZTAP(Zirconia toughened alumina ceramic particles)reinforced HCCI(high chromium cast iron)matrix composites,the quenching process was *** reinforced HCCI matrix composites were prepared by infiltration method with gravity sand *** thermal expansion curves of HCCI and the composites were measured at different cooling rates by *** microstructure of the HCCI matrix and the composites were characterized by X-ray diffraction,light microscopy,SEM,ESD,and *** tested mechanical properties include Rockwell hardness and impact *** deformation differences of HCCI and the composite at different cooling rates were obtained according to the test results of thermal expansion coefficient curve and changes in microstructure and mechanical properties,and air cooling was the most favorable for the composites to have good hardness and not easy to *** cooling rate during air cooling is approximately equal to 21℃/s in this *** the quenching process was air cooling,the impact toughness and hardness of the composites are 3.7 j/cm^(2) and 61.8 HRC,respectively,and the deformation difference between the composites and HCCI was 20μm at 300℃.

关键词： composites ZTAP quenching cooling rate microstructure thermal expansion

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酱卤鸭脖的特征风味物质剖面解析

现代食品科技 2024年第3期40卷 259-271页

作者：于恒和马一凡韩东黄峰李侠郭德斌张春晖宁夏大学食品与葡萄酒学院宁夏银川750021 中国农业科学院农产品加工研究所农业农村部农产品加工综合性重点实验室北京100193 江西煌上煌集团食品股份有限公司江西南昌330052

为构建酱卤鸭脖的特征风味指纹图谱,该文利用电子鼻、电子舌、气相色谱-质谱联用技术(Gas Chromatography-Mass Spectrometry,GC-MS)和高效液相色谱技术(High Performance Liquid Chromatography,HPLC)结合气味活性值(Odor Activity Value,OAV)、滋味活性值(Taste Activity Value,TAV)和味精当量(Equivalent Umami Concentration,EUC),对3款市售酱卤鸭脖(W牌、j牌、H牌)的特征风味进行剖面解析。结果表明,W牌、j牌和H牌中分别鉴定出44、37、32种挥发性风味物质。其中丁香酚、芳樟醇、肉桂酸乙酯、茴香脑等因具有较高OAV和特殊香气被划定为3种鸭脖共有的特征挥发性风味物质,可贡献甜香、果香和脂香。电子鼻结果则表明3种鸭脖在含硫化合物和氮氧化合物上存在差异;谷氨酸、丙氨酸、5,-肌苷酸、5,-鸟苷酸因TAV>1被确定为3种酱卤鸭脖的特征滋味物质,对鲜味和甜味贡献突出。此外,H牌的EUC值(4.41 g MSG/100 g)显著高于其他两组(Pj牌和W牌鸭脖,这也与电子舌检测结果保持一致。该研究可以为酱卤鸭脖特色风味保持及产品风味改善提供理论依据。

关键词：酱卤鸭脖特征挥发性风味物质特征滋味物质剖面解析

Chemical Quenching of Positronium in CuO/Al2O3 Catalysts

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Chinese Physics Letters 2011年第1期28卷 193-196页

作者： zhang Hong-jun LIU Zhe-Wen CHEN Zhi-Quan WANG Shao-jie Hubei Nuclear Solid Physics Key Laboratory Department of Physics Wuhan University Wuhan 430072

CuO/Al2O3 catalysts were prepared by mixing CuO and environment of the catalysts are characterized by positron v-AI203 nanopowders. Microstrueture and chemical annihilation spectroscopy. The positron annihilation lifetime measurements reveal two long lifetime components 73 and τ4, which correspond to ortho-positronium （o- Ps） annihilating in mierovoids and large pores, respectively. With increasing CuO content from 0 to 40 wt%, both 3-4 and its intensity I4 show significant decrease, which indicates quenching effect of o-Ps. The para-positronium （p-Ps） intensities derived from multi-Gaussian fitting of the coincidence Doppler broadening spectra also decreases gradually with increasing CuO content. This excludes the possibility of spin-conversion of positronium. Therefore, the chemicM quenching by CuO is probably responsible for the decrease of o-Ps lifetime. Variation in the o-Ps annihilation rate A4 （1/T4） as a function of CuO content can be well fitted by a straight line, and the slope of the fitting line is （1.83 ± 0.05） × 10^7 s-1.

关键词： METALS -- Quenching POSITRONIUM COPPER oxide ALUMINUM oxide CATALYSTS MICROSTRUCTURE POSITRON annihilation

Deep Bayesian local crystallography

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npj Computational Materials 2021年第1期7卷 1649-1660页

作者： Sergei V.Kalinin Mark P.Oxley Mani Valleti junjie zhang Raphael P.Hermann Hong Zheng Wenrui zhang Gyula Eres Rama K.Vasudevan Maxim Ziatdinov Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Bredesen Center for Interdisciplinary Research The University of TennesseeKnoxvilleTN 37996USA Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Materials Science Division Argonne National LaboratoryArgonneIL 60439USA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Present address:State Key Laboratory of Crystal Materials&Institute of Crystal Materials Shandong UniversityJinanShandong 250100China

The advent of high-resolution electron and scanning probe microscopy imaging has opened the floodgates for acquiring atomically resolved images of bulk materials,2D materials,and *** plethora of data contains an immense volume of information on materials structures,structural distortions,and physical *** this knowledge regarding local physical phenomena necessitates the development of the mathematical frameworks for extraction of relevant ***,the analysis of atomically resolved images is often based on the adaptation of concepts from macroscopic physics,notably translational and point group symmetries and symmetry lowering ***,we explore the bottom-up definition of structural units and symmetry in atomically resolved data using a Bayesian *** demonstrate the need for a Bayesian definition of symmetry using a simple toy model and demonstrate how this definition can be extended to the experimental data using deep learning networks in a Bayesian setting,namely rotationally invariant variational autoencoders.

关键词： symmetry local resolved

Stand history is more important than climate in controlling red maple (Acer rubrum L.) growth at its northern distribution limit in western Quebec, Canada

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journal of Plant Ecology 2015年第4期8卷 368-379页

作者： Yun zhang Yves Bergeron Xiu-Hai Zhao Igor Drobyshev Institut de recherche sur les forêts Universitédu Québec en Abitibi-Témiscamingue(UQAT)445 boul.de l’UniversitéRouyn-NorandaQuébec J9X 5E4Canada Key Laboratory for Forest Resources&Ecosystem Processes of Beijing Beijing Forestry UniversityBeijing 100083P.R.China Swedish University of Agricultural Sciences Southern Swedish Forest Research CentrePO Box 49Alnarp SE-23053Sweden Present address:National Plateau Wetlands Research Center Southwest Forestry UniversityKunming 650224P.R.China.

Aims We examined growth of red maple(Acer rubrum l.)to evaluate environmental controls of its northern distributional limit in Eastern North america and its potential response to future climate *** We collected growth data from nine sites located along a 300-km transect(47-49°N),which included frontier population of red maple and covered three bioclimatic domains in western *** ana-lyzed three growth variables:growth rates during the first 30 years of maple lifespan,cumulative basal area increment(ba I)over the most recent decade(2000-2009)and annual growth rate over the whole tree lifespan ranging from 58 to 112 *** also examined growth sensitivity to climate by using response function *** Findingsthree different proxies of maple absolute growth(initial growth rate,ba I during 2000-09 and mean diameter growth rate)indicated a better growth with an increase in *** speculate that stand history effectively overrode the direct effects of colder climate on maple growth along the s-N *** of maple in the southern sites likely occurred in canopy gaps,whereas in the north it was contingent upon large disturbances such as stand-replacing fires,which apparently provided more favorable light environment for maple growth than canopy *** annual growth variability,which reflects effects of annual weather on growth and is largely independent from the absolute growth rate,was significantly affected by monthly climate,suggesting a positive effect of higher summer temperature in the northern part of the transect(48-49°N)and a negative effect of summer drought in the south(47-48°N).In the future,the natural and human disturbance regimes will be dominant controls of the actual biomass productivity of red maple at the northern limit of its present distribution *** effects of climate on maple growth would likely be less important in this context,and will likely entail negative effect of increased summer drought

关键词： biomass productivity climate change dendrochronology ecotone hardwoods species migration