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Photoluminescence enhancement of red-emitting GdVO_4:Eu and YVO_4:Eu phosphors by adding zinc

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j.urnal of Rare Earths 2013年第1期31卷 13-17页

作者： K.Park j.Kim K.Y.Kim j.Y.Kim Y.Kim S.j.Dhoble Faculty of Nanotechnology and Advanced Materials Engineering Sejong University Department of Advanced Materials Engineering Hoseo University Department of Chemistry and Institute of Basic Sciences Dankook University Department of Physics R.T.M. Nagpur University

We synthesized the rare-earth activated Ro.94_xEuo.06ZnxVO4 （R： Gd and Y; 0〈_x〈_0.08） phosphors with a spherical mor- phology and a smooth surface by the ultrasonic spray pyrolysis. The annealed Ro.94_xEuo.06ZnxVO4 crystallized in the tetragonal zircon type structure, belonging to the space group of I41/amd. The incorporation of a small amount of Zn to Ro.94Euo.06VO4 improved the emission characteristics. The emission intensities of the Gdo.88EUo.06Zno.06VO4 and Yo.9Euo.06Zno.04VO4 phosphors at 619 nm were 72% and 2 1% stronger than those of the Gdo,94Euo.06VO4 and Yo.94Euo.06VO4 phosphors, respectively. We demonstrated that the addi- tion of Zn to Ro.94Euo.06VO4 was quite effective for improving the photoluminescent properties.

关键词： rare earths photolurninescence vanadate ultrasonic spray pyrolysis

Introduction to IUMRS World Materials Summits

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Progress in Natural Science:Materials International 2011年第2期21卷 187-188页

作者： j.an j.CARVAj.L Physics and Crystallography of Materials and Nanomaterials(FiCMA-FiCNA) Universitat Rovira i Virgili43007TarragonaSpain

The concept of IUMRS World Materials Summits initiated in *** Lian Zhou,president at that time of IUMRS,led several discussions during some informal 1UMRS meetings in Beij.ng,Xian,Ningbo and Shanghai with the various IUMRS member societies about the future possible developments of the Internationals Union for Materials Research *** one evening boat tour on a lake close to Shanghai in 2005 it emerged the suggestion of organizing conferences on the role of materials for future energy

关键词： World will

Synthesis of a chiral tricyclo[5.2.1.02.6]-deca-4,8-dien-3-one

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Chinese j.urnal of Chemistry 1995年第3期13卷 284-287页

作者： LIU, ZY ZHANG, j CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

In recent years we have been interested in the synthesis of natural products by retro Diels-Alder reaction.A rogod ,p;eci;e tricyclo[5.***.1.0-deca-4,8-dien-

关键词： CHIRAL TRICYCLODECADIENONE ESTRAPENTANENOL DIELS-ALDER REACTION QUINONE

Antioxidants in Food and Chronic Degenerative Diseases

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Biomedical and Environmental Sciences 1996年第Z1期 117-123页

作者： j. K. CANDLISH AND N. P. DAS (Biochemistry Department, National University of Singapore,Kent Ridge Crescent, Singapore 0511)

Both preventive and chain breaking antioxidants have a role in the limitation of free radical damage. Some of these may be regarded as "classical", like vitamins E and C but others are more recently discovered, such as the flavonoids, widespread in plant tissues, and the muscle constituents anserine and carnosine. The maj.r conditions in which the role of antioxidants is under intense investigation include coronary artery disease, cancer and diabetes. There are theoretical underpinnings for the efficacy of antioxidants in each of these, with the protection of low density lipoprotein (in respect of the first) being exceptionally *** attention is now being focussed on the flavonoids, which are surprisingly pleiotropic in their effects. For one of them, quercetin, over a dozen seemingly independent biologica1 effects can be listed, including the inhibition of low density lipoprotein *** also inhibit peroxidation in foodstuffs, as opposed to *** is much controversy over antioxidant supplementation policies, some authorities recommending a massive programme of supplementation for all ages and classes, others stressing the value of the traditional mixed diet. This matter is unlikely to be resolved soon,but in the meantime sensible supplementation policies should be continued for those most vulnerable, that is, babies and the aged

关键词： Free Antioxidants in Food and Chronic Degenerative Diseases

Euler Deconvolution with Improved Accuracy and Multiple Different Structural Indices

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j.urnal of China University of Geosciences 2008年第1期19卷 72-76页

作者： G R j.Cooper School of Geosciences University of the Witwatersrand Johannesburg 2050 South Africa

Euler deconvolution is a semi-automatic interpretation method that is frequently used with magnetic and gravity data. For a given source type, which is specified by its structural index （SI）, it provides an estimate of the source location. It is demonstrated here that by computing the solution space of individual data points and selecting common source locations the accuracy of the result can be improved. Furthermore, only a slight modification of the method is necessary to allow solutions for any number of different Sls to be obtained simultaneously. The method is applicable to both evenly and unevenly sampled geophysical data and is demonstrated on gravity and magnetic data. Source code （in Matlab format） is available from ***.

关键词： semi-automatic interpretation magnetics gravity geophysics.

Adventures and lessons of an American biochemist in China

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Protein & Cell 2011年第8期2卷 601-603页

作者： Christopher j.Vavricka CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

It’s very interesting how events often lead up to each other seemingly by chance,but appear almost perfectly planned out when looking *** the past two years,I have worked as an International Young Scientist Research Fellow at the Institute of Microbiology,Chinese Academy of Sciences in Beij.ng,*** people ask me,especially Chinese graduate students,why an American would choose to come to China as a postdoctoral researcher.

关键词： looking doctor perfectly

ESCA　STUDY　OF　DICHLOROZIRCONOCENE／METHYLALUMINOXANE　OLEFIN　POLYMERIZATION　CATALYST　SYSTEM

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Chinese Chemical Letters 1996年第1期7卷 67-70页

作者： Tian, j.Huang, BT CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA

An investigation has been undertaken by use of ESCA in the characterization of the central metal(Zr)of dichlorozirconocene/methylaluminoxane homogeneous olefin Polymerization *** change of electron density shown by a shift in ESCA signals (181.8- 182.7eV) indicates that the catalytic species are 'canon-like'. Within the range of detecting sensitivity of ESCA spectrometer , only a part of the new catalytic derivative was formed. The influence of complexion time and Al Zr ratio on the formation of the catalytic zirconocene cation has also been investigated.

关键词： ESCA STUDY OF CATALYST DICHLOROZIRCONOCENE

Subvellerolactone　C，　a　New　Lactarane　Sesquiterpene　from　Lactarius　Subvellereus

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Chinese Chemical Letters 1996年第12期7卷 1097-1099页

作者： Zhang, j.Feng, XZ CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA BEIj.NG UNION MED COLL BEIJING 100050PEOPLES R CHINA

Subvellerolactone C(I), a new 3, 8-oxa-13-hydroxy-1 acrar-6-en-5-oic acid γ-lactone was isolated from the fruit bodies of Lactarius subvellereus (Russulaceae), and its structure was elucidated by means of spectroscop... 详细信息

关键词： Subvellereus Lactarius New Sesquiterpene Lactarane

Metal-free acyl-directed electrophilic C–H borylation using j.st BBr3

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Science China Chemistry 2019年第12期62卷 1547-1548页

作者： Michael j.Ingleson School of Chemistry University of Edinburgh

The considerable utility of organoboranes in synthesis is firmly established,which is in a large part due to the power of the Suzuki-Miyaura cross-coupling reaction for con・structing C-C ***,discovering simple new routes to form desirable organoboranes continues to be of significant *** that directly transform C-H into C-B are particularly desirable,especially if borylation occurs with excellent site selectivity and without precious metal catalysts due to their low crustal abundance,high cost and toxicity.

关键词： desirable organo bonds