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Quantum-Mechanical Study of Small Au2Pdn （n=1 ～ 4） Clusters

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Communications in Theoretical Physics 2006年第1X期46卷 155-160页

作者： guo Jian-jun yang Ji-Xian DIE Dong Institute of Applied Physics Xihua University Chengdu 610039 China

Gold-doped palladium clusters, Au2Pdn （n=1～4）, are investigated using the density functional method B3LYP with relativistic effective core potentials （RECP） and LANL2DZ basis set. The possible geometrical configurations with their electronic states are determined, and the stability trend is investigated. Several low-lying isomers are determined, and many of them are in electronic configurations with a high-spin multiplicity. Our results indicate that the palladium-gold interaction is strong enough to modify the known pattern of bare palladium clusters, and the lower stability as the structures grow in size. The present calculations are useful to understanding the enhanced catalytic activity and selectivity gained by using gold-doped palladium catalyst.

关键词： Au-Pd clusters geometrical configuration density functional method

First Principle Calculation on AunAg2 （n = 1 - 4） Clusters

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Communications in Theoretical Physics 2007年第2X期48卷 348-352页

作者： guo Jian-jun yang Ji-Xian DIE Dong School of Physics and Chemistry Xihua University Chengdu 610039 China

The first-principles method based on density-functional theory is used to investigate the geometries of the lowest-lying isomers of AunAg2 （n = 1 - 4） clusters. Several low-lying isomers are determined, and many of them in electronic configurations with a high spin multiplicity. The stability trend of Ag-doped Aun dusters is compared to that of pure Aun clusters. Our results indicate that the inclusion of two Ag atoms in the clusters lowers the cluster stability, indicating higher stability as the structures grow in size. The bigger energy difference between the Aun and AunAg2 curves as the structures grows in size. This information will be useful to understanding the enhanced catalytic activity and selectivity gained by using silver-doped gold catalyst.

关键词： first-principle calculation geometrical configuration Au-Ag clusters bimetallic clusters

Primary Study on Effects of New Rare Earth Agro-Materials on Potato

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Journal of Rare Earths 2004年第z1期22卷 265-268页

作者： yang Qifeng Mao Wanhu Wang Jiachen Xing guo yang jun Liu Xiangsheng Gansu Provincial Agro-Technique Extension Centre Lanzhou 730020 China Gansu Provincial Agro-Technique Extension Centre Lanzhou 730020 China National Rare Earth Centre for Agriculture Beijing 100088 China DingXi County Agro-Technology Extension Centre Gansu 730008China National Rare Earth Centre for Agriculture Beijing 100088 China National Rare Earth Centre for Agriculture Beijing 100088 China

Using common phosphate as a check, we studied the growth and yield of potato by new rare earth agro-materials including rare earth phosphate (base fertilizer), rare earth whole plant nutrient fertilizer, and amino acid chelated rare earth ( top dressing), which were used in a single or mixed way in Dingxi city, Gansu *** results are as follows that ( 1 ) After using new rare earth materials, the plant height increases by 0.4 ～ 5.6 cm and the ripen period is delayed by 4 ～ 9 d.(2) They can improve the potato economic characteristics, enhance productivity, decrease black leg and late *** disease index is decreased by 1.6% ～ 10.6%, single plant potato number increases by 0.3 ～ 0.5, and single plant yield increases by 80 g ～ 130 g.(3) The effect of increased yield is significant, and mixed use is better than single *** the single material treatments, rare earth phosphate is the best, rare earth whole plant nutrient fertilizer and amino acid chelated rare earth are the second, and the increased rate are 14.5%, 8.4%, 9.2% so the material mixture-rare earth phosphate mixed of rare earth whole plant nutrient fertilizer or with amino acid chelated rare earth is economically useable, and increase rate are 25.2% and 24.4% compared with common phosphate.

关键词： potato economic characteristics diseases yield economic useable

Theoretical study of magnetic lens with parallel beam matched

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Nuclear Science and Techniques 2017年第2期28卷 12-17页

作者： guo-jun yang Zhuo Zhang Tao Wei Yi-Ding Li Xiao-Ding Zhang Jin-Shui Shi Institute of Fluid Physics Chinese Academy of Engineering Physics Key Laboratory of Pulsed Power Chinese Academy of Engineering Physics

The magnetic lens(Zumbro lens) is a critical part in proton radiography. Traditionally the matched beam for Zumbro lens in proton radiography is a virtual point source beam, which is not suitable for some cases, such as cylindrical samples. In these cases, a parallel beam is more appropriate. In this paper, a method, which uses quadrupole beamline, is proposed for designing a magnetic lens with parallel beam matched. Theoretical analysis is given. The results show that the matched beam for this lens is indeed parallel beam, while the major merits of Zumbro lens are inherited. Following this method, a theoretical design based on the 11-Me V cyclotron is presented.

关键词： Proton radiography Magnetic lens Chromatic blur Parallel beam Match

A Novel Flavonoid Glucoside from Anoectochilus roxburghii （Wall,） Lindl.

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Journal of Integrative Plant Biology 2006年第3期48卷 359-363页

作者： Chun-Nian He Chun-Lan Wang Shun-Xing guo jun-Shan yang Pei-Gen Xiao Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China

Eight compounds were isolated from the ethyl acetate- and n-butanol-soluble fractions of the ethanollc extract of the whole plant of Anoectochllus roxburghll（Wali.） Lindi. （Orchidaceee）. On the basis of spectroscopic methods, the structures of these compounds were elucidated as quercetin-7-O-β-D-[6＂-O-（trans-feruloyi）]- giucopyranosids （compound 1）, 8-C-p-HydroxybenzyiquerceUn （compound 2）, isorhamnetin-7-O-β-D- giucopyranoside （compound 3）, isorhamnetin-3-O-β-D-giucopyranoside （compound 4）, kaempferoi-3-O-β-D- giucopyranoside （compound 5）, kaempferoi-7-O-β-D-giucopyranoside （compound 6）, 5-hydroxy-3＇,4＇,7- trimethoxyfiavonoi-3-O-β-D-rutinoside （compound 7）, and isorhamnetin-3-O-β-D-rutinoside （compound 8）. Of the compounds isoisted, compound 1 was a new flavonoid giucoside and exhibited strong scavenging activity against the 1,1-diphenyi-2-picryihydrazyi free radical, whereas the ethanolic extract showed weak activity. Compounds 2-8 were obtained from this family for the first time.

关键词： Anoectochilus roxburghii quercetin-7-O-β-D-[6"-O-(trans-feruloyl)]-glucopyranoside radical-scavenging activity.

Epigallocatechin-3-gallate affects the growth of LNCaP cells via membrane fluidity and distribution of cellular zinc

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第6期10卷 411-421页

作者： jun-guo yang Hai-ning YU Shi-li SUN Lan-cui ZHANG guo-qing HE Undurti N. DAS Hui RUAN Sheng-rong SHEN Department of Food Scienee and Nutrition Zhejiang University Hangzhou 310029 China College of Pharmaceutical Sciences Zhejiang University of Technology Hangzhou 310032 China Tea Research Institute Guangdong Academy of Agricultural Sciences Guangzhou 510640 China UND Life Sciences 13800 Fairhill Road #321 Shaker Heights OH 44120 USA

Objective:To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate carcinoma LNCaP cells. Methods: We examined changes in cellular morphology and membrane fluidity of LNCaP cells, distribution of cellular zinc, and the incorporated portion of EGCG after treatments with EGCG, Zn2+, and EGCG+Zn2+. Results: We observed an alteration in cellular morphology and a decrease in membrane fluidity of LNCaP cells after treatment with EGCG or Zn2+. The proportion of EGCG incorporated into liposomes treated with the mixture of EGCG and Zn2+ at the ratio of 1:1 was 90.57%, which was significantly higher than that treated with EGCG alone (30.33%). Electron spin resonance (ESR) studies and determination of fatty acids showed that the effects of EGCG on the membrane fluidity of LNCaP were decreased by Zn2+. EGCG accelerated the accumulation of zinc in the mitochondria and cytosol as observed by atomic absorption spectrometer. Conclusion: These results show that EGCG interacted with cell membrane, decreased the membrane fluidity of LNCaP cells, and accelerated zinc accumulation in the mitochondria and cytosol, which could be the mechanism by which EGCG inhibits proliferation of LNCaP cells. In addition, high concentrations of Zn2+ could attenuate the actions elicited by EGCG.

关键词： Epigallocatechin-3-gallate (EGCG) Zinc LNCaP Membrane fluidity

Development of a Multiplex PCR for Diagnosis of Staphylococcus aureus, Escherichia coli and Bacillus cereus from Cows with Endometritis

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Agricultural Sciences in China 2011年第10期10卷 1624-1629页

作者： SUN Dong-bo WU Rui HE Xian-jing WANG Shuang LIN Yun-cheng HAN Xu WANG Yue-qiang guoTing-ting WU guo-jun yang Ke-li College of Animal Science and Veterinary Medicine Heilongjiang Bayi Agricultural University Daqing 163319 P.R.China

Staphylococcus aureus, Escherichia coli and Bacillus cereus are the major agents of cow endometritis in dairy cows. A multiplex PCR （SEB-mPCR） was established based on the conserved genes of S. aureus, E. coli and B. cereus, and the detection limits were 103, 102 and 103 CFU mL-1, respectively. SEB-mPCR could not amplify genomic DNA of pathogenic bacteria of other common bovine diseases. A total of 309 vaginal discharge samples from cows with endometritis were tested by SEB-mPCR. Of the samples, 23.95% had the three kinds of bacteria detected, 17.15% had S. aureu and E. coli, 9.39% had E. coli and B. cereus, and 9.71% had S. aureus and B. cereus. The rates of infections with S. aureus, E. coli and B. cereus were 11.35, 16.18 and 9.06%, respectively. Therefore, SEB-mPCR has a potential as a diagnosis tool for endometritis in dairy cows.

关键词： bovine endometritis multiplex PCR S. aureus E. coli B. cereus