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Irradiation Damage of Oxide Dispersion Strengthened Ferritic Steel after Recrystallization

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 160-164页

作者： Benfu Hu Shunmi Peng H Takahashi(Material science and Engineering School, university of science and technology Beijing, Beijing 100083, china)(faculty of Engineering, Hokkado university, Sapporo 060, Japan) Material science and Engineering School University of Science and Technology Beijing Beijing 100083 China faculty of Engineering Hokkado University Sapporo 060 Japan

The evolution of secondary defects and the characteristics of the void swelling of electrons irradiated Oxide Dispersion Strengthened Ferritic Steels (ODS steels) after recrystallization were studied. It was found that recrystallization increases the void swelling of ODS steel as compared with solution and injected He+ + D+ *** are two size ranges of voids formed in recrystallized ODS steel during irradiation, and bubbles can be preferential sites for the void formation. Polycrystal with low density of defects is formed, and sites where point defects disappear by irradiation decrease. This is the main reason for the increase of void swelling of ODS steel after recrystallization.

关键词： ODS steel recrystallization, electron irradiation

A novel evolutionary algorithm for global numerical optimization with continuous variables

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Progress in Natural science:Materials International 2008年第3期18卷 345-351页

作者： Wenhong Zhaoa,b, Wei Wang a, Yuping Wang a, a School of Computer science and technology, Xidian university, Xi’an 710071, china b faculty of science, Xidian university, Xi’an 710071, china School of Computer science and technology Xidian University Xi’an 710071 China faculty of science Xidian University Xi’an 710071 China

Evolutionary algorithms (EAs) are a class of general optimization algorithms which are applicable to functions that are multimodal, non-differentiable, or even discontinuous. In this paper, a novel evolutionary algorithm is proposed to solve global numerical optimiza- tion with continuous variables. In order to make the algorithm more robust, the initial population is generated by combining determinate factors with random ones, and a decent scale function is designed to tailor the crossover operator so that it can not only find the decent direction quickly but also keep scanning evenly in the whole feasible space. In addition, to improve the performance of the algorithm, a mutation operator which increases the convergence-rate and ensures the convergence of the proposed algorithm is designed. Then, the global convergence of the presented algorithm is proved in detail. Finally, the presented algorithm is executed to solve 24 benchmark problems, and the results show that the convergence-rate of the proposed algorithm is much faster than that of the compared algorithms.

关键词： Evolutionary algorithm Decent scale function Global numerical optimization Global convergence

Theoretical analysis of polarization properties for tilted fiber Bragg gratings

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science china(Information sciences) 2010年第2期53卷 390-397页

作者： XU Ou 1 , LU ShaoHua 2 & JIAN ShuiSheng 2 1 faculty of Information Engineering, Guangdong university of technology, Guangzhou 510006, china 2 Institute of Lightwave technology, Beijing Jiaotong university, Beijing 100044, china 1. faculty of Information Engineering Guangdong University of Technology Guangzhou 510006 China2. Institute of Lightwave Technology Beijing Jiaotong University Beijing 100044 China

The polarization properties for tilted fiber Bragg gratings (TFBGs) are investigated theoretically based on coupled-mode theory and Mueller matrix method. The expression of wavelength-related polarizationdependent loss (PDL) for TFBGs with different tilt angles is derived and calculated. Simulation results are compared, and the results indicate that the polarization capability of TFBGs with 45° angle is stronger than other TFBGs with smaller angles. The degree of polarization for unpolarized light passing TFBGs is also simulated to further evaluate the polarization properties for various tilt angles. In addition, the relationship between physical parameters of a TFBG and its polarization capability is discussed.

关键词： coupled-mode theory degree of polarization (DOP) Mueller matrix method polarization dependent loss (PDL) tilted fiber Bragg gratings

Seasonal influence on the development of parthenotes and cloned embryos in pigs

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Progress in Natural science:Materials International 2007年第10期17卷 1172-1176页

作者： Zhang Kun1, Zhang Yunhai3,4, Pan Dengke5, Ma Yufang1, Wei Hengxi1, Zhang Jian6, Li Xuyang7, Wang Shaohua1, Li Yan2, Dai Yunping1,2 and Li Ning1(1. State Key Laboratory for Agrobiotechnology, College of Biological science, china agricultural university, Beijing 100094, china 2. JiPulin Biotech Ltd., Beijing 100094, china 3. Danish Institute of agricultural sciences, 8830 Tjele, Denmark 4. College of animal science and technology, Anhui agricultural university, Hefei 230036, china 5. Institute of animal sciences, Chinese Academy of agricultural sciences, Beijing 100094, china 6. animal Clinical Hospital, china agricultural university, Beijing 100094, china 7. Hebei Minghui Group of Pigs Breeding, Sanhe 065200, china) State Key Laboratory for Agrobiotechnology College of Biological Science China Agricultural University Beijing 100094 China JiPulin Biotech Ltd. Beijing 100094 China Danish Institute of agricultural sciences 8830 Tjele Denmark College of animal science and technology Anhui Agricultural University Hefei 230036 China Institute of animal sciences Chinese Academy of Agricultural Sciences Beijing 100094 China animal Clinical Hospital China Agricultural University Beijing 100094 China 7. Hebei Minghui Group of Pigs Breeding Sanhe 065200 China

Seasonal influence on the developmental ability of porcine embryos was studied by comparisons of the number of cumulus-oocytes-complexes (COCs) per ovary pair and meiotic maturation ability of oocytes in different seasons; and by the observations on developmental competence of the parthenogenetic oocytes and cloned embryos collected from different seasons. We found that the number of COCs per ovary pairs was significantly higher in spring compared to the other seasons (P<0.05). However, no significant difference was found in the rate of oocytes progressing to MⅡ in four seasons (P<0.05). In addition, the rate of blastocyst formation of parthenogenetic embryos in summer was obviously declined compared to the other seasons (P<0.05), and an increased blastocyst rate of cloned porcine embryos was found in spring compared to autumn and winter (P<0.05). The results suggest that there should be a seasonal influence on the developmental competence of porcine embryos.

关键词： pig cloned parthenogenetic season

EST-derived microsatellites in P seudosciaena crocea and their applicability to related species

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Acta Oceanologica Sinica 2010年第6期29卷 83-91页

作者： YE Hua WANG Xiaoqing GAO Tianxiang WANG Zhiyong College of animal science and technology Hunan Agricultural University Changsha 410128 China Key Laboratory of science and technology for Aquaculture and Food Safety Fisheries College/Fisheries Biotechnology Institute Jimei University Xiamen 361021 China Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 China

Simple sequence repeat （SSR） markers were obtained for the large yellow croaker Pseudosciaena crocea using 1 205 expressed sequences tags （ESTs） from the NCBI *** for 48 ESTSSR loci were designed and screened with 30 *** specimens captured from Guanjingyang sea area in Fujian Province of *** of the loci were polymorphic,which were amplified with 3 to 11 alleles per locus and the mean of *** observed and expected heterozygosity per locus ranged from 0.091 to 0.844 （mean 0.544） and from 0.118 to 0.892 （mean 0.644）,*** information content （PIC） ranged from 0.115 to 0.866 （mean 0.593）.The results for cross-species amplification of the 16 large yellow croaker EST-SSRs on ***,***,***,*** and *** revealed that 14,12,11,7 and 6 loci were successfully amplified with 1 to 10 alleles with an average of 4.5 per locus,respectively,which are suitable for population genetics studies of these species and useful for phylogenetic relationship analysis among these ***,this study provides a set of type I markers for population genetics studies and genome mapping for large yellow croaker and its closely related species.

关键词： Pseudosciaena crocea EST-SSRs genetic diversity cross-species amplification

An Inquiry into Cultivation of New-generation Farmers

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Asian agricultural Research 2012年第1期4卷 40-44页

作者： KONG Dong-qing, LIU Fu-jun yunnan agricultural university, kunming 650201, china

This article expounds the necessity of the transformation from traditional farmers to modern new farmers: the building of new socialist countryside needs modern new farmers; the coordination of urban-rural integration development needs the transformation from traditional farmers to modern new farmers; the development of modern agriculture needs the transformation from traditional farmers to modern new farmers. Then it analyses the characteristics and role of new-generation farmers, and presents the way to accelerate cultivation of new-generation farmers: make sound laws and regulations, to lay solid foundation for cultivation of new-generation farmers; create conditions, to provide funds guarantee for cultivation of new-generation farmers; make scientific planning, to promote regular, systematized and standardized training work for new-generation farmers; focus on education, to promote the overall quality of new-generation farmers; innovate upon content, to meet the needs of development of new-generation farmers; highlight focus, to intensify competitiveness training for returning-home migrant workers.

关键词： "New generation" New famers Cultivation

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玉米自交系主要数量性状的配合力分析

西南农业学报 1997年第1期10卷 49-52页

作者：吴渝生云南农业大学农学院昆明650201

按Griffing方法4模型Ⅰ，研究8个玉米自交系的28个完全双列杂文组合6个性状的配合力。结果表明，同一性状的一般配合力在不同自交系间有很大差异，在同一自交系不同性状间屯有一定差异。在卢量方面，云248的一般配合力最高，特殊配合力... 详细信息

按Griffing方法4模型Ⅰ，研究8个玉米自交系的28个完全双列杂文组合6个性状的配合力。结果表明，同一性状的一般配合力在不同自交系间有很大差异，在同一自交系不同性状间屯有一定差异。在卢量方面，云248的一般配合力最高，特殊配合力以云147最高。一般配合力高的亲本易产生特殊配合力高的组合，但也不排除从一般配合力都不高的双亲获得较高特殊配合力组合的可能性。

关键词：玉米自交系数量性状配合力

Spectrofluorimetric determination of terbium with terephthalic acid

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Rare Metals 2002年第4期21卷 255-259页

作者： ZHAO Guohu and ZHAO JunBasic science Department, Gansu agricultural university, Lanzhou 730070, china Basic science Department Gansu Agricultural University Lanzhou 730070

A Spectrofluorimetric method has been developed for the determination ofterbium(Ⅲ) based on the formation of a complex with terephthalic acid [benzene-1, 4-dicarboxylicacid (TPA)] in slightly acidic aqueous solution in the presence of gelatin. Terbium ion can form astable complex with TPA with the stoichiometry of 1:2. The best excitation and maximum emissionwavelengths are observed at 260 nm and 545 nm, respectively. The fluorescence intensity of terbiumcomplex gets the strongest within 20 min and remains stable up to 10 h, and it is proportional toterbium(Ⅲ) concentration in the range of 4.0x10^(-5)-1.6x10^(-7) mol·L^(-1) under the optimumconditions. The fluorescence system has good selectivity, sensitivity and stability. The relativestandard deviation is still within +-4% in the presence of 1200-fold amounts of the other lanthanideions when the concentration of terbium(Ⅲ) is 1.0x10^(-6) mol·L^(-1) and common co-existing ionshardly interfere the determination. It has been applied to the direct fluorimetric determination oftrace terbium (Ⅲ) in rare earth ores and oxides.

关键词： terbium spectrofluorimetry terephthalic acid gelatin

Effects of chemical activation and season on birth efficiency of cloned pigs

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science china(Life sciences) 2009年第7期52卷 657-664页

作者： MA YuFang1,2,LI Yan3,WEI HengXi1,LI QiuYan3,FANG Rui1,ZHAO Rui3,ZHANG Kun1,XUE Kai1,LOU YanKun1,DAI YunPing3,LIAN LinSheng2 & LI Ning1 1 State Key Laboratory of Agrobiotechnology,College of Biological sciences,china agricultural university,Beijing 100193,china 2 College of animal science and technology,china agricultural university,Beijing 100193,china 3 Beijing Genprotein Biotechnology Company,Beijing 100193,china 1. State Key Laboratory of Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100193 China 2. College of animal science and technology China Agricultural University Beijing 100193 China 3. Beijing Genprotein Biotechnology Company Beijing 100193 China

The effects of chemical activation on birth efficiency of cloned pigs were studied by investigating the developmental process from porcine oocyte activation to birth of cloned *** different activation methods were used:(i) Electroporation(Ele);(ii) Ele followed by incubation with 6-dimethylaminopurine(6-DMAP);and(iii) Ele followed by a treatment with cycloheximide(CHX).In experiment 1,the rates of cleavage,developmental rates and cell number of porcine parthenogenetic(PA) embryos were investigated in the three treatment *** experiment 2,NT embryos produced by the three different activation treatments were compared for the rates of cleavage,development and cell ***,the effects of Ele and Ele+CHX activation methods on birth efficiency of cloned pigs were *** activated oocytes treated by combination activation generally showed a higher(P<0.05) blastocyst rate and produced more expanded blastocysts than oocytes activated with *** rates of cleavage and total cell number of parthenotes were not significantly *** embryos activated with 6-DMAP developed into blastocyst and expanded blastocyst stages at a significantly(P<0.05) higher rate than those treated with Ele,but the developmental capability was dramatically decreased in NT *** the CHX activation method,the NT embryo blastocyst rate was substantially(P<0.05) increased although the production of expanded blastocysts was not significantly different from that by the other two *** birth rate of cloned pigs increased in the CHX group,though the rate was not significantly different from *** effects of season on developmental rate of the porcine PA embryos and birth rate of cloned pigs were also examined in our *** oocytes collected in the spring had higher developmental capabilities than those collected in the ***,no difference in birth rate of the cloned pigs was found between the oocytes collected in the two *** re

关键词： parthenogenetic activation chemical activation nuclear transfer pig season