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Extreme central L-values of almost prime quadratic twists of elliptic curves

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Science China Mathematics 2023年第12期66卷 2755-2766页

作者： Shenghao hua bingrong huang Data Science Institute and School of Mathematics Shandong UniversityJinan 250100China

In this paper,we prove the extreme values of L-functions at the central point for almost prime quadratic twists of an elliptic *** an application,we get the extreme values for the Tate-Shafarevich groups in the quadra... 详细信息

关键词： extreme value quadratic twist central L-value elliptic curve almost prime

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三代木麻黄林中稀土元素的含量与分布

稀土 2003年第3期24卷 51-55页

作者：刘强毕华黄澜彭少麟沈承德海南师范学院生物系海南海口571158 海南师范学院地理系资源与环境研究所海南海口571158 中国科学院华南植物研究所广东广州510650 中国科学院广州地球化学研究所广东广州510640

研究了海南岛滨海砂土上3代木麻黄林生态系统中稀土元素含量和分布。土壤稀土元素分布模式基本上与世界土壤和我国土壤相同,呈负斜率分布,轻稀土相对富集,土壤和植物都存在不同程度的Eu负异常。木麻黄林下砂土的稀土元素总含量很低,从第... 详细信息

研究了海南岛滨海砂土上3代木麻黄林生态系统中稀土元素含量和分布。土壤稀土元素分布模式基本上与世界土壤和我国土壤相同,呈负斜率分布,轻稀土相对富集,土壤和植物都存在不同程度的Eu负异常。木麻黄林下砂土的稀土元素总含量很低,从第1代林到第3代林分别为:42.716、45.416、14.457μg/g。植物体中的稀土元素的总含量也很低。从第1代林到第3代林,木麻黄根ΣREE分别为0.722、1.444、1.887μg/g,枝分别为0.354、0.318、0.267μg/g,叶分别为0.492、1.312、0.715μg/g。第3代木麻黄林土壤中ΣREE最低,但根中的ΣREE最高,叶中的ΣREE高于第1代林。表明幼林对稀土元素摄取强烈。在土壤植物—系统中稀土元素分布为土壤>根>叶>粗枝。

关键词：木麻黄生态系统稀土元素含量分布

Syntheses and Liquid Crystal Properties of New Rare Earth Sandwich Type Heteropoly Compounds

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Chemical Research in Chinese Universities 1999年第4期15卷 364-366页

作者： bi Li-hua LIU Jing-hua WANG En-bo huang Ru-dan YU Yong-zhang WU Ping-song Department of Chemistry Northeast Normal UniversityChangchun 130024P.R.China

Mapping of Mutant Gene prbs Controlling Poly-Row-and-Branched Spike in Barley (Hordeum vulgare L.)

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Agricultural Sciences in China 2011年第10期10卷 1501-1505页

作者： huang bi-guang WU Wei-ren Key Laboratory for Genetics Breeding and Multiple Utilization of Crops Ministry of Education/College of Crop Science Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China

A row-type mutant of barley named poly-row-and-branched spike （prbs） was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produces branched spikes with irregular multiple rows. Genetic analysis indicated that the mutant phenotype was caused by a recessive gene prbs, and the PRBS locus had a recessive epistatic effect on an independent locus （denoted as Vrsx） conferring the variation of two-rowed spike vs. six-rowed spike. This study aimed to map PRBS as well as Vrsx using simple sequence repeats （SSR） markers. We developed an F2 population from a cross between the prbs mutant and a six-rowed cultivar Putianwudu for the gene mapping. As the two target loci interacted to result in a segregation ratio of two-rowed type：six-rowed type：prbs=9：3：4 in the population, we adopted a special strategy to map the two loci. PRBS was mapped between SSR markers HvLTPPB and Bmag0508A on the short arm of chromosome 3H, with distances of 24.7 and 14.3 cM to the two markers, respectively. Vrsx was mapped between SSR markers Bmag0125 and Bmag0378 on chromosome 2H, with distances of 6.9 and 15.3 cM to the two markers, respectively. This suggests that Vrsx should be the known locus Vrs1, which predominantly controls row-type variation in barley cultivars, and PRBS is a new locus related to the row type of spikes in barley.

关键词： barley row type prbs mapping SSR

Periodic Folded Wave Patterns for(2+1)-Dimensional Higher-Order Broer-Kaup Equation

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Communications in Theoretical Physics 2008年第10期50卷 827-831页

作者： huang Wen-hua College of Science Huzhou University Huzhou 313000 China Shanghai Institute of Mathematics and Mechanics Shanghai University Shanghai 200072 China

A general solution including three arbitrary functions is obtained for the (2+1)-dimensional higher-orderBroer-Kaup equation by means of WTC truncation *** proper multiple valued functions and Jacobielliptic functions in the seed solution,special types of periodic folded waves are *** long wave limit theseperiodic folded wave patterns may degenerate into single localized folded solitary wave *** interactions ofthe periodic folded waves and their degenerated single folded solitary waves are investigated graphically and are foundto be completely elastic.

关键词： higher-order Broer Kaup equation WTC truncation method periodic folded wave

Machine learning study on time-temperature-transformation diagram of carbon and low-alloy steel

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Journal of Iron and Steel Research International 2023年第5期30卷 1032-1041页

作者： Xiao-ya huang biao Zhang Qiang Tian Hong-hui Wu bin Gan Zhong-nan bi Wei-hua Xue Asad Ullah Hao Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Beihang UniversityBeijing 100191China High Temperature Materials Research Division Central Iron and Steel Research InstituteBeijing 100081China Beijing Advanced Innovation Center for Materials Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Advanced High Temperature Materials Central Iron and Steel Research InstituteBeijing 100081China School of Materials Science and Engineering Liaoning Technical UniversityFuxin 123099LiaoningChina Department of Mathematical Sciences Karakoram International UniversityGilgit-Baltistan 15100Pakistan

Time-temperature-transformation(TTT)diagram plays a critical role in designing appropriate heat treatment process of steels by describing the relationship among holding time,temperature,and quantities of phase *** predictions for TTT diagrams of new steel rapidly and accurately is therefore of much practical importance,especially for costly and time-consuming experimental ***,TTT diagrams for carbon and low-alloy steels were predicted using machine learning *** commonly used machine learning(ML)algorithms,backpropagation artificial neural network(BP network),LibSVM,k-nearest neighbor,Bagging,and Random tree,were adopted to select appropriate models for the *** results illustrate that Bagging is the optimal model for the prediction of pearlite transformation and bainite transformation,and BP network is the optimal model for martensite ***,the ML framework composed of Bagging and BP network models was applied to predict the entire TTT ***,the ML models show superior performance on the prediction of testing samples than the commercial software JMatPro.

关键词： Time-temperature-transformation diagram Carbon steel Low-alloy steel Machine learning Prediction framework

The Existence of (v,4,1) Disjoint Difference Families with a Prime Power

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 643-648页

作者： Dian-hua Wu Jian-xiao Yang bi-chang huang Department of Mathematics Guangxi Normal University Guilin 541004 China

A （v, k, λ） difference family （（v, k, λ）-DF in short） over an abelian group G of order v, is a collection F=（bi｜i ∈ I} of k-subsets of G, called base blocks, such that any nonzero element of G can be represented in precisely A ways as a difference of two elements lying in some base blocks in F. A （v, k, λ）-DDF is a difference family with disjoint blocks. In this paper, by using Weil＇s theorem on character sum estimates, it is proved that there exists a （p^n, 4, 1）-DDF, where p = 1 （rood 12） is a prime number and n ≥1.

关键词： Difference family disjoint difference family optimal optical orthogonal codes character sum

Preparation and Microstructure of Highly-Oriented LaNiO_3 Thin Films by RF Sputtering Method

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Chinese Journal of Aeronautics 2006年第B12期19卷 142-145页

作者： CHENG Xing-hua QIAO Liang bi Xiao-fang School of Materials Science and Engineering BeO＇ing University of Aeronautics and Astronautics Beijing 100083 China

In an attempt of being used as buffer layers and electrodes for the textured BaTiO3 （BTO） ferroelectric thin films, highly （100）-oriented LaNiO3 （LNO） thin films of different thicknesses were deposited directly on Si （100） substrate with radio-frequency （RF） magnetron sputtering method. It is observed that the substrate temperatures and the film thicknesses bring main influences on the microstructures and orientation of the thin film. The effects of the thicknesses and substrate temperatures on the orientation of the films were studied on the LNO films of different thicknesses. The highly （100）-oriented LNO thin films were obtained at the substrate temperature of 600℃. The existence of epitaxially grown BTO films indicates that the oriented LNO thin films obtained in this work could be used as a buffer layer for epitaxial growth.

关键词： LaNiO3 film perovskite orientation risistivity

In vitro propagation of a medicinal plant: Tripterygium wilfordii Hook f.

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Forestry Studies in China 2009年第3期11卷 174-178页

作者： CHEN bi-hua Forestry biotechnology Research and Development Center Fujian Academy of Forestry Sciences Fuzhou 350012 P. R. China Key Laboratory of Timber Forest Breeding and Cultivation for Mountainous Areas in Southern China State Forestry Administration Fuzhou 350012 P. R. China

In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP （2.0 mg.L^-1） and NAA （0.1 mg.L^-1）. The optimal multiplication medium was a modified MS medium supplemented with BAP （1.0 mg.L^-1） and NAA （0.1 mg.L^-1）. This yielded a multiplication rate of 2.4 for each subculture. Slightly more than 92% of shoots rooted when cultured on a modified MS medium containing IBA （0.2 mg.L^-1） and activated charcoal （0.5 mg.L^-1）. Activated charcoal promoted both a strong and a high rooting rate during the rooting phase. Plantlets were transferred to pots for a short acclimatization stage in a greenhouse where 95% of the plantlets survived. This highly reproducible procedure can be adopted for large-scale propagation of T. wilfordii.

关键词： in vitro propagation Tripterygium wilfordii Hook f. multiplication rooting activated charcoal