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Effects of two types of vitamin B6 on growth Performance,Body Composition and Serum Biochemical Indices of Litopenaeus vannamei

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Effects of two types of vitamin B6 on growth Performance,Bod...

Catalytic Asymmetric Cyclopropanation using a New Chiral β-Diketone Cu (Ⅱ) Complex as a Catalyst

The 14th International Symposium on Fish Nutrition & Feeding

作者： Wei-liang Jiang~(1,2*),Jun-ming Cao~1,Yan-hua Huang~1,Jun-ru Hu~1,Hong-xia Zhao~1, Bing Chen~1,Han-bing Lan~1 1 Institute of animal science,Guangdong Academy of agricultural sciences,Guangzhou 510640, china 2 South china agricultural university,college of animal science,Guangzhou 510640,china

An 8 weeks feeding trial was conducted to determine the effects of two types(encapsulated and ordinary )of vitaminB on growth performance,body composition and serum biochemical indices of Litopenaeus vannamei.A semi-purified basal diet was formulated using vitamin-free casein,gelatin and fishmeal as protein *** shrimps(IBW 0.36g) were fed the basal diet and 7 test diets supplemented with 30,60,90,120mg /kg diet encapsulated vitaminB (Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ) and 30,60,90mg/kg diet ordinary type vitaminB(Ⅵ,Ⅶ,Ⅷ),respectively. Upon analyzed,the content of vitaminB in 8 diets was 0.22,24.3,52.7,83.7,108.6,30.4,52.7 and 77.6 mg /kg *** results showed that survival rate,weight gain rate,protein efficiency ratio,feed conversion rate,HSI and ALT activities,TP,GLU and HDL content in serum and body composition were not significantly different(P>0.05) between the group of adding encapsulated vitaminBand the group of adding ordinary type vitaminB when added the same *** gain rate reached the peak in groupⅣ,but increased in groupⅧ.Survival rate and protein efficiency ratio reached the peak in groupⅢ,but increased in groupⅧ.Feed conversion rate and HSI reached the lowest in groupⅢ,the former decreased in groupⅥand the later increased in groupⅧ.Activities of ALT and content of TP reached the highest level in groupⅢ,decreased in groupⅥ.The content of GLU and HDL reached the highest in groupⅣ,decreased in groupⅧ. Muscle protein content reached the highest in groupⅢ,decreased in groupⅥ.The results indicated that optimal supplementation of encapsulated vitamin B in Litopenaeus vannamei was estimated to be 60mg/kg diet.

关键词： Litopenaeus vannamei vitaminB6 FCR body composition Serum Biochemical Indices

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Chinese Chemical Letters 1998年第7期9卷 607-608页

作者： Yu XU Zhong Yi WANG and Tian Pa YOU(Department of Chemistry, university of science and Technology of china, Hefei 230026) Department of Chemistry Univ. of Sci./Technology of China Hefei 230026 China

A new chiral β-diketone Cu (Ⅱ) catalyst was synthesized and used for the asymmetric cyclopropanation of styrene with diazoester. A high optical yield (~90%) was achieved. The effect of the structure of substrate on the enantioselectivity was studied. Both chendcal yield and optical yield being reduced when the steric bulky substrate was employed. The reaction mechanism and the chiral model of the transition state are under fufther investigation.

关键词： Asymmetric cyclopropanation β-Diketone Cu (Ⅱ) Complex

A new method for removing mixed noises

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science china(Information sciences) 2011年第1期54卷 51-59页

作者： LI Bing1,3,LIU QuanSheng1,2,XU JiaWei1 & LUO XiaoJun1 1School of Mathematics and Computation science,Changsha university of science&Technology, Changsha 410076,china 2LMAM,Université de Bretagne-Sud,Campus de Tohannic,Vannes 56017.Université Européenne de Bretagne,France 3Department of Mathematics,Zhongshan Polytechnic,Zhongshan 528404,china School of Mathematics and Computation science Changsha University of Science & Technology Changsha China Department of Mathematics Zhongshan Polytechnic Zhongshan China LMAM Université de Bretagne-Sud Vannes France Université Européenne de Bretagne Bretagne France

We first introduce a similarity assumption to describe the similarity phenomenon in natural images, and establish a similarity principle which supplies a simple mathematical justification for the non-local means filter in removing Gaussian *** the similarity principe in an adapted way,we then propose a new algorithm,called mixed noise filter(MNF)to remove simultaneously a mixture of Gaussian and random impulse *** experiments show that our new filter improves significantly the trilateral filter in removing mixed noises,and that it is as effcient as the non-local means filter in removing Gaussian noises,and as good as the trilateral filter in removing random impulse noises.

关键词： mixed noises Gaussian noises random impulse noises image restoration nonlinear filters trilateral filter non-local means filter denoising similarity principle

γ-Hydroxy-α,β-acetylenic esters:asymmetric syntheses and applications

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science china Chemistry 2010年第1期53卷 21-35页

作者： GAO Ge1 & PU Lin2 1Department of Chemistry,Sichuan university,Chengdu 610064,china 2Department of Chemistry,university of Virginia,Charlottesville,Virginia 22904-4319,USA Department of Chemistry Sichuan University Chengdu China Department of Chemistry University of Virginia Charlottesville USA

γ-Hydroxy-α,β-acetylenic esters are versatile synthetic precursors to many organic *** paper reviews the synthesis of chiral γ-hydroxy-α,β-acetylenic esters by asymmetric reduction of γ-oxo-α,β-acetylenic esters,enantioselective addition to aldehydes in the presence of chiral catalysts,and diastereoselective addition to chiral *** preparation of racemic γ-hydroxy-α,β-acetylenic esters is also *** are provided for the application of γ-hydroxy-α,β-acetylenic esters in organic synthesis.

关键词： γ-hydroxy-α β-acetylenic ester asymmetric enantioselective diastereoselective

Diffuse interstellar absorption bands

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science china(Physics,Mechanics & Astronomy) 2009年第4期52卷 489-501页

作者： XIANG FuYuan1,2,LIANG ShunLin2 & LI AiGen2,3 1 Faculty of Materials,Photoelectronics and Physics,Xiangtan university,Xiangtan 411105,china 2 Department of Physics and Astronomy,university of Missouri,Columbia,MO 65211,USA 3 Purple Mountain Observatory,Chinese Academy of sciences,Nanjing 210008,china Faculty of Materials Photoelectronics and Physics Xiangtan University Xiangtan China Department of Physics and Astronomy University of Missouri Columbia USA Purple Mountain Observatory Chinese Academy of Sciences Nanjing China

The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

关键词： astrophysics interstellar matter interstellar extinction diffuse interstellar band circumstellar environment

On the dynamics of xn+1=δxn-3t+1+xn-4t+1/A+xn-4t+1

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商丘师范学院学报 2010年第9期26卷 42-46页

作者： HONG Liang1,YANG Yanhua2(1.Institute of Physics Electronic Engineering,Xinyang Normal university,Xinyang 464000,china 2.Department of Computer science,Xinyang agricultural college,Xinyang 464000,china) Institute of Physics Electronic Engineering Xinyang Normal UniversityXinyang 464000China Department of Computer science Xinyang Agricultural CollegeXinyang 464000China

In this paper,we consider the following difference equationxn+1=δxn-3t+1+xn-4t+1/A+xn-4t+1 n=0,1,….where t∈{1,2,…},and the initial values are *** investigate the global character of solutions of the above differen... 详细信息

关键词： difference equation boundedness bounded solution global attractor

Spatial Chaos of Bose-Einstein Condensates in a Cigar-Shaped Trap

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Communications in Theoretical Physics 2007年第7期48卷 107-111页

作者： LI Fei REN Zhong-Zhou LUO Hai-Lu SHU Wei-Xing Department of Physics,Nanjing university,Nanjing 210008,chinaWU Qin School of Basic Medical science,Guangdong Medical college,Dongguan 523808,china Department of Physics Nanjing University Nanjing 210008 China School of Basic Medical science Guangdong Medical College Dongguan 523808 China

The spatial chaos of Bose-Einstein condensates in a cigar-shaped trap is *** a system with asteady current,we construct the general solution of the 1st-order *** the boundedness condition of thegeneral solution, we obtain the Melnikov function predicting the onset of *** unpredictability of the system's dis-tribution of atom density is also theoretically *** a ^(23)Na system meeting the perturbation oondition,numericalsimulations show the existence of chaos,which is in accordance with our analytical *** simulations of a^(87)Rb system dissatisfying the perturbation condition also demonstrate that there exists chaos in the *** casewithout a current is also investigated.

关键词： Bose-Einstein condensates Melnikov function chaos

Stereological Analysis of Peritubular Cells in Aging Mouse Testes

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Journal of Reproduction and Contraception 2011年第2期22卷 107-112页

作者： Yan XIA Wei-jie ZHU Jing LI Institute of Reproductive Immunology College of Life Science and Technology Jinan University Guangzhou 510632 China Deptment of Pathophysiology Medical College Jinan University Guangzhou 510632 China

Objective To analyse quantitative changes of testicular peritubular cells in aging mice, and meanwhile investigate age-related changes in both Sertoli cells and germ cells with stereology. Methods Thirty male Kunming mice were enrolled in this study. The aged mice （n=15） were 18 months old. The young mice （n=15） were 6 months old, as the control. Haematoxylin and eosin staining was used to observe histological changes. Pathological evaluation rules of assignment scores were made to evaluate. Stereology techniques were applied to quantitatively analyse histological structure of the testicular tissues. Results Compared with young group, pathologic assignment scores of aging group were significantly higher （P〈0.05）. Diameter of seminiferous tubules in aging mice was atrophied significantly （P〈0.05）. Germ cell numerical density and Sertoli cell volume density of aging group were reduced significantly compared with young group （P〈0.05）. No significant differences were found in peritubular cell parameters compared with young group （P〉0.05）. Conclusion The pathological assignment scores suggest a succession of changes on the testis with age. The stereological numbers demonstrate damaged Sertoli cells and decreased germ cells, which is indicative of spermatogenic disturbance. However, no significant quantity changes of peritubular cells is observed in aging mice.

关键词： peritubular cell Sertoli cell germ cell aging stereology

EFFECTS　OF　RETAINED　AUSTENITE　ON　DUPLEX　MICROSTRUCTURE　OF　MARTENSITE　AND　LOWER　BAINITE

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 59-64页

作者： WEN Cui’e LIN Jianguo ZHOU Yajian(Department of Materials science,Beijing university of Aeronautics and Astronautics,Beijing 100083,china) Beijing Univ of Aeronautics and Astronautics Beijing China

The morphology and amount of the retained austenite in the duplex microstructure of martensite and tower bainite of a tow,alloy cold die steel(it is called GD steel for short) with high strength and high toughness have been *** thermal and mechanical stabilities of the retained austenite were *** the effects of retained austenite on the mechanical properties of the steel were *** results show that the morphology and amount of retained austenite vary with silicon content in the *** austenite with high stability was responsible for the simultaneous increase in strength and toughness of the *** duplex microstructure of martensite and abnormal lower bainite of the steel with the maximum silicon content exhibits a relatively good strength-toughness combination.

关键词： martensite bainite die steel retained austenite