检索结果-南通市图书馆

Estimates of genetic and phenotypic parameters for weight and length in Paralichthys olivaceus(Temminck et Schlegel)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2011年第6期30卷 58-64页

作者： TIAN Yongsheng XU Tianjun LIANG You CHEN Songlin Key Laboratory for Sustainable utilization of Marine Fisheries resources Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China Laboratory for Marine Living resources and Molecular Engineering College of Marine ScienceZhejiang Ocean University Zhoushan 316000 China

The complete diallel cross design was employed to estimate the genetic parameters of the growth of Japanese flounder （Paralichthys olivaceus）. A total of 60 full-sib families were cultivated and two growth-related traits, body weight （BW） and body length （BL）, were examined at average 2. 3 and 8 months of age respectively, with 1 800 individuals measured in each age group （30 per family）. Based on the additive-dominance-maternal-effect genetic analysis model, the restricted maximum likelihood approach was used to estimate various （co）variance components. The results showed that narrow-sense heritability estimates of BW and BL were respectively： 0.2. ± 0.01 and 0.2. ± 0.02.at 2.months of age, 0.32.± 0.02.and 0.30 ± 0.04 at 3 months of age, 0.48 ± 0.04 and 0.40 ± 0.05 at 8 months of age; broad-sense heritability estimates were respectively： 0.44 ± 0.02.and 0.54 ± 0.04 at 2.months of age, 0.35 ± 0.01 and 0.36 ± 0.03 at 3 months of age, 0.49 ± 0.03 and 0.45 ± 0.04. All heritabilities were statistically significant （P 0.05）. Additive genetic correlations between BW and BL at 2. 3 and 8 months of age were consistently positive and highly significant （P 0.01）： 0.93 ± 0.02. 0.95 ± 0.03 and 0.92.± 0.03 respectively. Maternal effect was significant （P 0.05） only at 2.months of age, and was not detected at 3 and 8 months of age. According to the heritability estimates, the mass selection strategy should be efficient for the breeding of Japanese flounder.

关键词： Paralichthys olivaceus heritability genetic correlation genetic mating design diallel cross maternal effect

High Energy Micro-arc Alloying of ZM5 Mg Alloy by Mg-Y Electrode under Liquid

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2011年第S4期40卷 181-184页

作者： Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and resources utilization of Ministry of Education,Laser Processing {2. center,College of Materials and Metallurgy,Wuhan university of Science& Technology,Wuhan 430081,china Wuhan Univ Sci &Technol Laser Proc Res Ctr Key Lab Ferrous Met & Resources Utilizat Minist EducColl Mat & Met Wuhan 430081 Peoples R China

High-energy micro-arc alloying (HEMAA) is a consumable electrode,micro-welding process which uses electrical pulses that are typically three orders of magnitude shorter than in other pulse welding *** durations of a few microseconds combined with pulse frequencies in the 0.1 to 2.kilohertz range thus allow substrate heat dissipation over ～99% of the duty cycle while heating only about 1%.The cooling rates may approach 105 to 106 ℃/s,depending on *** obtained coating can produce unique corrosion and tribological *** require no special surface preparation and nearly any metal,alloy or cermets can be applied to metal *** paper details experimental results when alloying Mg base alloy ZM5,using Mg-Y electrodes with a water-based dielectric *** morphology and the composition of the alloying was analyzed by scanning electron microscope(SEM) and energy dispersive X-ray analysis(EDX).At the discharge energies employed,a thin recast layer thickness and rougher layers were formed on the *** layers were in general *** analysis showed that the Y transferred from the solid electrodes to the workpiece surface.

关键词： high-energy micro-arc alloying (HEMAA) surface alloying/modification Mg alloy Mg-Y

在线全文

学校读者我要写书评

暂无评论

宁夏引黄提水灌区水价测算方法

水电能源科学 2011年第6期29卷 140-142页

作者：任杰宁夏大学土木与水利工程学院宁夏银川750021 宁夏节水灌溉与水资源调控工程技术研究中心宁夏银川750021 旱区现代农业水资源高效利用工程研究中心宁夏银川750021

为有效提高提水灌区水资源利用效率,基于水价计算及水费收取问题,以宁夏引黄灌区为例,依据《水利工程供水价格管理办法》,采用完全成本定价法评价了水资源价值,并测算了宁夏某灌区水价,为灌区水价管理提供了依据。

关键词：提水灌区水价计算方法宁夏

A new orchid Paphiopedilum guangdongense and its molecular evidence

在线全文

学校读者我要写书评

暂无评论

Journal of Systematics and Evolution 2010年第5期48卷 350-355页

作者： 1 Li-Jun CHEN 1,2.3Zhong-Jian LIU 4You-Yu LI 1Li-Qiang LI 1(Shenzhen Key Laboratory for Orchid Conservation and utilization,The national Orchid Conservation {2. of china/The Orchid Conservation and research {2. of Shenzhen,Shenzhen 518114,china) 2.The {2. for Biotechnology and BioMedicine,Graduate School at Shenzhen,Tsinghua university,Shenzhen 518055,china) 3(College of Forestry,South china Agricultural university,Guangzhou 510642.china) 4(The Nature Reserve of Dawuling of Guangdong Province,Xinyi 52.000,Guangdong,china) (Shenzhen Key Laboratory for Orchid Conservation and utilization The National Orchid Conservation Center of China/The Orchid Conservation and Research Center of Shenzhen Shenzhen 518114 China) (The center for Biotechnology and BioMedicine Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China) (College of Forestry South China Agricultural University Guangzhou 510642 China) (The Nature Reserve of Dawuling of Guangdong Province Xinyi 525000 Guangdong China) *Correspondence: Zhong-Jian LIU *Correspondence: ?Author for correspondence. E-mail: liuzj@*** Tel.: 86-755-2.712.59 Fax: 86-755-2.71192..

A new Paphiopedilum entity found in southern Guangdong was studied taxonomically by means of internal transcribed spacer of nuclear ribosomal DNA analysis in addition to morphological and phytogeographical *** entity is similar to Paphiopedilum gratrixianum(Masters)Rolfe morphologically,from which it differs by having narrower leaves not wider than 2.cm and lacking purple spots toward abaxial base,pale green dorsal sepal veined with pale purplish brown and not heavily spotted with purple,and staminode subtruncate and mucronate at *** analysis of internal transcribed spacer sequences of this entity and its allies came to the same conclusion that the entity is a member of Paphiopedilum section Paphiopedilum and closely related to but distinct from *** a result,it is treated here as a new species,Paphiopedilum guangdongense ***&***.

关键词： new species nrITS Orchidaceae Paphiopedilum guangdongense.

Dicamba and Sugar Effects on Callus Induction and Plant Regeneration from Mature Embryo Culture of Wheat

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences in china 2010年第1期9卷 31-37页

作者： REN Jiang-ping,WANG Xin-guo and YIN Jun national Engineering research {2. for Wheat/Henan Agricultural university,Zhengzhou 450002.P.R.china [a] national Engineering research {2. for Wheat/Henan Agricultural university Zhengzhou 450002 P.R. China

To establish a highly efficient plant regeneration system for wheat genetic transformation, the effects of three different concentrations of dicamba and two different sugar types on callus induction and plant regeneration from mature embryo cultures were evaluated. Callus induction and plant regeneration were obtained from mature embryos of two commercial cultivars Zhoumai 18 and Yumai 34 （Triticum aestivum L.） cultured on L3 basal medium. The results showed that the efficiency of mature embryo culture was significantly influenced by the genotypes, sugar types and dicamba concentrations. 4 mg L^-1 dicamba proved the best effective for inducing embryogenic callus and also gave the highest proportion of plants regenerated across the two cultivars. Substitution of maltose by sucrose significantly improved the plant regeneration efficiency in both cultivars. There was a significant interaction between genotype-by-sugar types, and sugar types-bydicamba concentrations. Overall, Zhoumai 18 gave the highest frequency of plant regeneration （82.65%） when dicamba concentration was 4.0 mg L^-1 and with sucrose in initial callus induction. These results will facilitate genetic transformation work with elite wheat.

关键词： wheat mature embryo tissue culture plant regeneration

Surface Top Graphology,Corrosion and Microhardness of Oxygen Diffusion Hardened Pure Titanium Alloy TA4 after Laser Surface Melting

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2011年第S4期40卷 185-189页

作者： Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and resources utilization of Ministry of Education,Laser Processing {2. center,College of Materials and Metallurgy,Wuhan university of Science& Technology,Wuhan 430081,china Wuhan Univ Sci & Technol Laser Proc Res Ctr Key Lab Ferrous Met & Resources Utilizat Minist EducColl Mat & Met Wuhan 430081 Peoples R China

In the oxygen diffusion hardened condition,untreated and laser surface melted pure titanium alloy (TA4) by Nd:YAG pulsed laser,are hardened at temperatures of 650 to 700℃ with the end result being a passive,mechanically stable,abrasion resistant oxide ceramic rutile surface *** thickness of this surface layer depends on the time,temperature,and the microstructure of the Ti *** paper describes the results of x-ray diffraction analysis,scanning electron microscope (SEM),microhardness measurements,and corrosion resistance measurements of hardened pure and laser treated Ti *** oxygen diffusion hardened titanium alloy after laser surface melted samples (L-TA4) had a more pronounced grain structure and significantly higher roughness values than the untreated pure TA4 (U-TA4)*** L-TA4 samples also exhibited at least equivalent corrosion behavior and a definite increase in surface hardness compared to the U-TA4 *** results of this work suggest that laser surface melting plays a key role for effective oxygen diffusion hardening at 650-700℃ for pure and laser treated pure Ti alloys.

关键词： oxygen diffusion harden (ODH) titanium alloy laser surface melting corrosion

Further results on the margin explanation of boosting:new algorithm and experiments

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2012年第7期55卷 1551-1562页

作者： WANG LiWei 1,DENG XiaoCheng 2.,JING ZhaoXiang 1 & FENG JuFu 1 1 Key Laboratory of Machine Perception,MOE,Peking university,Beijing 100871,china 2.Microsoft Search Technology {2. Asia,Beijing 100080,china 1. Key Laboratory of Machine Perception MOE Peking University Beijing 100871 China2. Microsoft Search Technology Center Asia Beijing 100080 China

Understanding the empirical success of boosting algorithms is an important theoretical problem in machine *** of the most influential works is the margin theory,which provides a series of upper bounds for the generalization error of any voting classifier in terms of the margins of the training *** an equilibrium margin (Emargin) bound which is sharper than previously well-known margin bounds is *** this paper,we conduct extensive experiments to test the Emargin ***,we develop an efficient algorithm that,given a boosting classifier (or a voting classifier in general),learns a new voting classifier which usually has a smaller Emargin *** then compare the performances of the two classifiers and find that the new classifier often has smaller test errors,which agrees with what the Emargin theory predicts.

关键词： boosting margin Emargin theory

Provable efficient Certificateless Group Key Exchange Protocol

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Wuhan university Journal of Natural Sciences 2007年第1期12卷 41-45页

作者： CAO Chunjie MA Jianfeng MOON Sangjae Key Laboratory of Computer Networks and InformationSecurity Ministry of Education Xidian University Xi＇ an 710071Shaanxi China Mobile Network Security Technology research center Kyungpook National University Daeyu 702701 Korea

Certificateless public key cryptography （CL-PKC） avoids the inherent escrow of identity-based cryptography and does not require certificates to guarantee the authenticity of public keys. Based on CL-PKC, we present an efficient constant-round group key exchange protocol, which is provably secure under the intractability of computation Diffie-Hellman problem. Our protocol is a contributory key exchange with perfect forward secrecy and has only two communication rounds. So it is more efficient than other protocols. Moreover, our protocol provides a method to design efficient constant-round group key exchange protocols and most secret sharing schemes could be adopted to construct our protocol.

关键词： group key exchange certificateless public key cryptography provable security bilinear pairings

在线全文

学校读者我要写书评

暂无评论

无资料地区水文预报(PUB)不确定性研究

水电能源科学 2009年第4期27卷 7-10页

作者：杨邦任立良陈福容史俊超河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对无资料地区的水文过程模拟采用流量历时曲线率定法实现水文模型参数区域化,避开建立模型参数与流域特征值之间的相关关系,以流量历时曲线作为水文模型的拟合目标率定无资料地区参数。通过基于GLUE法的不确定性分析发现,相对于参数... 详细信息

针对无资料地区的水文过程模拟采用流量历时曲线率定法实现水文模型参数区域化,避开建立模型参数与流域特征值之间的相关关系,以流量历时曲线作为水文模型的拟合目标率定无资料地区参数。通过基于GLUE法的不确定性分析发现,相对于参数相关法,流量历时曲线率定法预报的不确定性对似然临界值取值更敏感,在高似然区不确定性更小,在低似然区则相反;优化调参通常更关注高似然区,因而应用流量历时曲线率定法推求无资料地区参数效果更好。

关键词：无资料地区水文模型水文预报不确定性 GLUE 参数区域化