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Induction of gyno-tetraploidy in Japanese fl ounder Paralichthys olivaceus

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Journal of Oceanology and Limnology 2020年第1期38卷 288-293页

作者： WANG Guixing ZHANG Xiaoyan SUN Zhaohui ZHAO Yaxian DU Wei cui jianbin HOU Jilun WANG Yufen Key Laboratory of Aquatic Genomics Ministry of AgricultureBeijing 100141China Beidaihe Central Experiment Station Chinese Academy of Fishery SciencesQinhuangdao 066100China Ocean College Agricultural University of HebeiQinhuangdao 066009China

Tetraploid fish are important for mass production of triploids in polyploid *** this study,we reported a novel protocol for artificial induction of tetraploidy by a combination of cold shock and hydrostatic pressure administered to gynogenetically developed eggs in Japanese flounder Paralichthys *** induction was carried out by activating the eggs with UV-irradiated sperm of red sea bream Pagrus major,administering a cold shock(0℃,5 to 45 min)3 min after fertilization to inhibit second polar body exclusion,incubating the eggs for 60 min at 17℃,and treating them with a 650 kg/cm2 hydrostatics pressure shock for 6 *** named the embryos gyno-tetraploids that developed from eggs after such *** hatching rate of the gyno-tetraploids ranged from 20.99%±3.66%to 36.01%±2.79%,and the tetraploid rate ranged from 80.00%to 100.00%.All-maternal inheritance was verified using 6 high-recombination-rate microsatellite *** method successfully induced *** successful induction of gyno-tetraploidy lays the foundation for triploidization of new varieties with improved economic traits of interest that can benefit commercial culture.

关键词： gynogenesis polyploidy chromosome manipulation mosaic

Construction and Optimization of English Linguistic System in the Context of Multi-dimensional Perspective and Interactive Teaching

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International Journal of Technology Management 2016年第10期 57-59页

作者： jianbin cui Xi'an University Xi'anShaanxi710065 China

With the improvement of the quality education in our country, the teaching reform of college English teaching has been carried out. In the college English teaching system, we need the network-based autonomous teaching mode, and effective evaluation system of English teaching is also necessary. A complete set of teaching evaluation system can truly reffect the teaching effect, and can promote the optimization of teaching activities as well. Therefore, in order to realize the effectiveness of English teaching and to expand the diversifi ed teaching mode, we need to build a complete set of English language system. Classroom teaching evaluation is one of the effective means to improve the teaching efficiency, which reffects the characteristics of college English courses. After the digitalization of the teaching methods, the network information produced in the teaching and management has obvious characteristics of large data. The optimized evaluation system of college English classroom teaching has realized the diversifi cation of evaluation subjects.

关键词： Interactive Teaching Multi-dimensional English Linguistic System Construction and Optimization.

DIFFICULTIES FOR NON-NATIVE TEACHERS OF ENGLISH IN ACCEPTING THE COMMUNICATIVE APPROACH

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Chinese Journal of Applied Linguistics 1996年第2期19卷 96-98页

作者： cui jianbin Weinan Teachers College

IntroductionTraditionally in China teachers use the Grammar-Translation *** focuses on teaching newvocabulary,and explaining the text sentence by *** this way,most students learn a lot ofvocabulary and knowledge of grammar,and native-like ***,when they listen orspeak in a real-world situation,they have no idea how to express themselves *** otherwords,they need not only to read and write,but also listen and speak in *** the future,they mayneed to attend international seminars or have discussions with foreign *** methodsmay not meet these needs whereby the Communicative Approach(C.A.)may be more effective.

关键词： sentence pronunciation listen grammar speak themselves discussions write usage subtle

Cobalt Single Atom-Catalyzed Formation of LiOH in Li-O_(2)Batteries via the Direct 4-Electron Oxygen Reduction Pathway

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CCS Chemistry 2024年第10期6卷 2502-2514页

作者： Kang Huang Hao Wan Zhichao Gong jianbin Liu Minmin Yan Jun Wu Chunyu cui Gonglan Ye Karsten Reuter Huilong Fei Advanced Catalytic Engineering Research Center of the Ministry of Education State Key Laboratory for Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082 Fritz-Haber-Institut der Max-Planck-Gesellschaft Berlin 14195

The formation of LiOH as the discharge product instead of Li_(2)O_(2)in Li-O_(2)batteries(LOBs)is highly desirable due to the associated drawbacks of Li_(2)O_(2)-based chemistry,which involves the generation of reactive oxygen intermediates responsible for substantial side ***,the current challenge lies in the formation pathway of LiOH,which typically requires the chemical hydrolysis of the hazardous LiO_(2)or Li_(2)O_(2)intermediate,posing risks to the battery ***,we report a direct 4e–electrochemical approach to LiOH enabled by a single atom catalyst(SAC)consisting of CoN_(3)moieties embedded in graphene(CoN_(3)-G),while Li_(2)O_(2)is formed on the metal-free nitrogen-doped graphene(NG).The direct 4e–LiOH pathway significantly reduces the parasitic reactions,resulting in negligible damage to the electrolyte and *** stands in strong contrast to the conventional 2e–Li_(2)O_(2)pathway mediated by NG and the indirect LiOH pathway by MnO_(2).Theoretical calculations further clarify that the presence of CoN_(3)sites enhances the adsorption of oxygen-containing intermediates like*OLiO and*Li_(2)O_(2),promoting the protonation of*Li_(2)O_(2)and the cleavage of the O–O bond to form *** work demonstrates a promising strategy to modulate the reaction pathways in LOBs and broadens the applications of SACs.

关键词： single atom catalyst LiOH Li-O_(2)batteries direct 4-electron oxygen reduction pathway selectivity

基于Schwarz-Christoffel变换的圆形隧道围岩应力分布特征研究

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应用数学和力学 2019年第10期40卷 1089-1098页

作者：崔建斌姬安召熊贵明陇东学院数学与统计学院甘肃庆阳745000 陇东学院能源工程学院甘肃庆阳745000 太原理工大学矿业工程学院太原030024

隧道围岩应力还原到实际区域的变换方法被越来越多地应用到工程实践中,对复杂形状围岩体内的隧道围岩应力计算方法和隧道围岩稳定性的研究具有重要的实践指导意义.该文建立了不规则岩体中开挖圆形隧道的力学模型,运用复变函数理论,通过... 详细信息

隧道围岩应力还原到实际区域的变换方法被越来越多地应用到工程实践中,对复杂形状围岩体内的隧道围岩应力计算方法和隧道围岩稳定性的研究具有重要的实践指导意义.该文建立了不规则岩体中开挖圆形隧道的力学模型,运用复变函数理论,通过映射函数Schwarz?Christoffel变换,得到复平面单位圆到隧道所处多边形岩体的映射函数,在复变函数数域内分析了多边形岩体应力的求解步骤,运用弹性力学理论等推导了不规则岩体中圆形隧道的复变应力函数?(ξ)和φ(ξ)的表达式,并得出围岩体任一点应力分量σρ和σθ的解析通式.通过具体算例分析可知,岩体形状对圆形隧道的稳定性有较大的影响,隧道所处4种形状下的围岩体最大应力值分布规律为:顶底板的最大应力值从六边形、五边形、四边形、圆形围岩体依次减小,帮部的最大应力值从圆形、四边形、五边形、六边形围岩体依次减小.

关键词：多边形围岩隧道 Schwarz-Christoffel变换平面应力围岩应力分布

矩形到任意多边形区域的Schwarz-Christoffel变换数值解法

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应用数学和力学 2019年第1期40卷 75-88页

作者：王玉风姬安召崔建斌陇东学院能源工程学院甘肃庆阳745000

运用Schwarz-Christoffel变换方法,建立多边形区域到带状区域共形映射数学模型.对于模型中的约束条件和奇异积分问题,根据Riemann(黎曼)原理,建立复参数与实参数互逆变换,消除非线性系统的约束条件;经过合理积分路径的确定,模型中的奇... 详细信息

运用Schwarz-Christoffel变换方法,建立多边形区域到带状区域共形映射数学模型.对于模型中的约束条件和奇异积分问题,根据Riemann(黎曼)原理,建立复参数与实参数互逆变换,消除非线性系统的约束条件;经过合理积分路径的确定,模型中的奇异积分转化为Gauss-Jacobi(高斯-雅可比)型积分;采用Levenberg-Marquardt算法对非线性系统模型进行求解.根据第一类椭圆函数性质,建立了矩形区域到带状区域共形映射数学模型,通过复参数椭圆函数的计算,得到矩形边界与带状区域边界的关系.最后,对8点对称多边形区域与27点不规则条带状区域计算,将不规则封闭区域边界映射到矩形区域边界,矩形区域内的正交网格,通过变换之后在多边形区域内依然满足正交性,为研究不规则区域到规则区域映射的数值计算奠定基础.

关键词： Schwarz-Christoffel变换复参数椭圆函数 Levenberg-Marquardt算法矩形区域多边形区域

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确定最佳聚类数的二阶差分统计法

安徽大学学报（自然科学版） 2017年第2期41卷 61-67页

作者：崔建斌姬安召张科陇东学院数学与统计学院甘肃庆阳745000 陇东学院能源工程学院甘肃庆阳745000 西北师范大学数学与统计学院甘肃兰州730070

多元统计数据的聚类是分析数据的一类非常重要方法,但是如何确定最佳聚类数往往是比较困难的.针对分析多元统计数据中应用最广泛的方法之一——K均值聚类方法,提出了一种新的二阶差分统计确定最佳聚类数的方法,并将其与CH统计法、Gap统... 详细信息

多元统计数据的聚类是分析数据的一类非常重要方法,但是如何确定最佳聚类数往往是比较困难的.针对分析多元统计数据中应用最广泛的方法之一——K均值聚类方法,提出了一种新的二阶差分统计确定最佳聚类数的方法,并将其与CH统计法、Gap统计法进行了对比.实证分析表明,论文所提方法更为简单而且有效.

关键词：二阶差分聚类最佳聚类数仿真实验

高碳锰铁渣摇炼热兑生产低碳锰铁合金工艺探索和实践

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铁合金 2022年第1期53卷 8-10页

作者：崔健斌中信锦州金属股份有限公司辽宁锦州121005

介绍了高碳锰铁渣摇炼硅铁粉后热兑入炉生产低碳锰铁的工艺流程和操作技术要点,通过生产实践开拓了低碳锰铁合金生产的新工艺思路。

关键词：高碳锰铁渣热兑硅铁粉摇炼

Early repair for infants with cleft lip and nose using bi-rectangle flap in nostril

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Early repair for infants with cleft lip and nose using bi-re...