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Interspecific Hybridization Between Crassostrea angulata and C. ariakensis

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Journal of Ocean University of China 2015年第4期14卷 710-716页

作者： YAO Tuo ZHANG Yuehuan YAN Xiwu WANG Zhaoping li dongchun SU Jiaqi YU Ruihai Fisheries College Ocean University of China Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of Oceanology Chinese Academy of Sciences Engineering Research Center of Shellfish Culture and Breeding of liaoning Province College of Fisheries and Life Science Dalian Ocean University

lnterspecific hybridization can generate heterosis, which is proven to be a useful tool in selective breeding programs for oyster culture. Crassostrea angulata and C. ariakensis are two important economic shellfish species in China. We conducted 2 × 2 reciprocal crosses to determine whether these two species can cross-fertilize and their hybrids can hatch, survive and perform hetero- sis. Fertilization was found symmetrical without delay. The rate of fertilization success of C. angulata ♀× C. ariakensis ♂ was lower than that of C. ariakensis ♀ x C. angulata ♂, and the success rate of both hybridizations was lower than that of two intraspecific crosses each. During the planktonic period, survival rate of the progeny was lower in the hybrid crosses than in the intraspecific crosses. On day 360, mean shell height of the progeny of C. angulata ♀ x C. angulata ♂ was highest, which was followed by that of C. angulata ♀ × C. ariakensis ♂, C. ariakensis ♀x C. ariakensis ♂ and C. ariakensis ♀× C. angulata ♂ in a descending order. Mor- phology of adults produced by the hybrid crosses was similar to that of C. angulata. Both hybrids underwent normal gonad devel- opment and produced mature gametes in the mating season. This study provided new insights into the quantitative traits in interspeci- fic crosses of Crassostrea species, thus being of guidance value for selective breeding of oyster.

关键词： Crassostrea angulata Crassostrea ariakensis interspecific hybridization gonad development heterosis

Research Progress in the Effect Evaluation of GLP1-1 Agonists

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Journal of Clinical and Nursing Research 2022年第1期6卷 22-25页

作者： dongchun li Yali Wang Xin liang Shaanxi University of Chinese Medicine Xianyang 712000Shaanxi ProvinceChina

Glucagon-like peptide-1(GLP-1)promotes insulin secretion,inhibits glucagon secretion,and repairs pancreatic islet cell function to enhance islet cell proliferation and ***,it includes a mechanism for weight loss and angiocarpy *** study covers the comparison of GLP-1 agonists with DPP-4 inhibitors and GLT-2 inhibitors,the mechanism of GLP-1 agonists,and its research possibilities based on a summary of current clinical tests of GLP-1 receptor agonists.

关键词： Diabetes GLP-1 receptor agonist Effect evaluation Adverse reaction

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TC4钛合金复合加载下超高周疲劳性能研究

振动与冲击 2022年第20期41卷 244-251页

作者：王博涵程礼李冬春空军工程大学航空工程学院西安710038 先进航空发动机协同创新中心北京100191

针对航空发动机压气机叶片在实际工况下的超高周疲劳断裂问题,研究了三种锻造温度下TC4钛合金三点弯曲–轴向拉伸复合加载的疲劳破坏行为。试验结果表明,S-N曲线呈直线下降型和双平台型,采用985℃近锻造时疲劳性能最好。随着应力幅值降... 详细信息

针对航空发动机压气机叶片在实际工况下的超高周疲劳断裂问题,研究了三种锻造温度下TC4钛合金三点弯曲–轴向拉伸复合加载的疲劳破坏行为。试验结果表明,S-N曲线呈直线下降型和双平台型,采用985℃近锻造时疲劳性能最好。随着应力幅值降低,裂纹由表面萌生向次表面萌生转变,断口形貌呈现准解理断裂特征。表面裂纹萌生于α晶界或α-β相界,由位错滑移堆积导致;而次表面裂纹萌生于刻面,由初生α相解理导致。疲劳寿命由裂纹萌生阶段主导,且所占比例随总寿命的增加而变大。双态组织中初生α含量和尺寸均小于等轴组织,且β转变组织含量更高,从而具备更好的疲劳性能。轴向拉伸改变了试件的轴向应力分布,有利于提高裂纹萌生于次表面的概率,使裂纹起源点向内部迁移。

关键词： TC4钛合金复合加载超高周疲劳 S-N曲线微观组织

激光冲击强化TC4微观组织演化及纳米晶形成

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中国激光 2022年第8期49卷 200-208页

作者：王博涵程礼李冬春空军工程大学航空工程学院飞行器与动力工程教研室陕西西安710038 先进航空发动机协同创新中心北京100191

为了揭示激光冲击强化诱导的表面纳米晶形成机制,通过电子背散射衍射(EBSD)和透射电镜(TEM)对TC4钛合金表层微观组织进行了分析。结果表明,试件表面冲击区域的相分布无明显变化,但平均晶粒尺寸由3.78μm下降至3.18μm,且高水平应变的分... 详细信息

为了揭示激光冲击强化诱导的表面纳米晶形成机制,通过电子背散射衍射(EBSD)和透射电镜(TEM)对TC4钛合金表层微观组织进行了分析。结果表明,试件表面冲击区域的相分布无明显变化,但平均晶粒尺寸由3.78μm下降至3.18μm,且高水平应变的分布更均匀。激光冲击强化使小角度晶界向大角度晶界转变,织构强度减弱且极向呈多向化分布,晶粒取向分布更随机。截面微观组织依次为表层纳米晶、次表层位错胞、高密度位错和内部带有低密度位错的基体粗晶。分析认为,表面纳米晶是由一系列复杂的位错运动引起的,符合连续动态再结晶机制。试件表面晶体畸变能最大,且瞬态温升高达755℃,因此动态再结晶过程进行得最充分。

关键词：激光技术激光冲击强化 TC4钛合金微观组织演化表面纳米晶连续动态再结晶

数据采集与监控系统(SCADA系统)在煤气调度中的应用

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自动化仪表 2000年第12期21卷 40-43页

作者：李东春广州市煤气公司广州510060

介绍了由ＥＬＰＲＯ公司ＴＬＣ系列模块组成的ＳＣＡＤＡ系统在煤气调度中的应用，具体介绍了系统的结构与配置、软件系统（ＣＩＴＥＣＴ）、ＲＴＵ的组成及特点、无线通信等技术问题。

关键词： SCADA系统煤气调度数据采集监控系统

Experimental Observation of Cubic C_3N_4 Compound in Carbon Nitride Thin Films

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Journal of Materials Science & Technology 1999年第5期15卷 480-482页

作者： Furen XIAO Dongli YU Yongjun TIAN Julong HE dongchun li and Wenkui WANG(College of Materials Science and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China To whom correspondence should be addressed E-mail: fhcl@*** ) Yanshan Univ Coll Mat Sci & Chem Engn Qinhuangdao 066004 Peoples R China

Cubic C3N4 compound in the C-N thin films on Si and NaCl substrates was prepared by ion beam sputtering of a pure graphite target with discharge gas of pure N2. X-ray photoelectron spectroscopy indicated that nitrogen atoms combined with sp2- and sp3- coordinated C atoms in the film, respectively. X-ray diffraction, selected area electron diffraction and high-resolution electron microscopy were used to identify the cubic C3N4 phase. The results reconfirm the ab initio calculations on metastable structure in C-N compounds

关键词： Thin Experimental Observation of Cubic C3N4 Compound in Carbon Nitride Thin Films Rev

Development of Solid Rocket Motor for Manned Launch Vehicle Escape System

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Aerospace China 2022年第1期23卷 19-26页

作者： li dongchun SHI Hongbin WEI Kunlong Xi’an Aerospace Solid Propulsion Technology Institute Xi'an 710025

The solid rocket motors for the escape system of China’s LM-2 F manned launch vehicle are described,the key technologies and technical innovations utilized are *** technical features and development of foreign manned launch abort systems are also *** development trends of the solid rocket motor for future Chinese manned launch vehicle escape systems are proposed,which can provide a reference for the future development of manned launch vehicle escape systems.

关键词： solid rocket motor manned launch vehicle escape system key technologies development trends

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推靠式旋转导向工具造斜能力影响因素

石油钻采工艺 2019年第4期41卷 460-466页

作者：李军李东春张辉王昊中国石油大学(北京)石油工程学院

旋转导向工具相比于滑动导向工具具有机械钻速快、摩阻扭矩小、水平位移延伸能力强、井眼轨迹易调控等优点。推靠式旋转导向工具引入国内市场后,总体应用情况较好,但在部分地区也出现了工具造斜能力不足的问题。根据底部钻具组合纵横弯... 详细信息

旋转导向工具相比于滑动导向工具具有机械钻速快、摩阻扭矩小、水平位移延伸能力强、井眼轨迹易调控等优点。推靠式旋转导向工具引入国内市场后,总体应用情况较好,但在部分地区也出现了工具造斜能力不足的问题。根据底部钻具组合纵横弯曲梁方法,建立了推靠式旋转导向工具变截面BHA力学模型以及井斜趋势角分析模型,并在此基础上分析了BHA结构参数、钻压、钻头各向异性和岩石可钻性对工具造斜能力的影响规律。分析结果表明,偏置力、第1跨钻柱长度及外径、第2跨钻柱外径、钻头侧向切削能力对工具造斜能力的影响较大。根据分析结果对推靠式旋转导向工具的底部钻具结构进行了优化,在塔中地区取得了较好的应用效果。

关键词：推靠式旋转导向工具力学模型底部钻具组合造斜能力

Chemical bond properties and M（?）ssbauer spectroscopy in (La1-xMx)2CuO4（M=Ba,Sr）

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Rare Metals 2002年第4期 299-303页

作者： GAO Faming, li dongchun, XIE Dianyang, TIAN Yongjun, and ZHANG Siyuan College of Materials Science and Chemical Engineering, Yanshan University, Qinghuangdao 066004, China Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China

By using the average band-gap model, the chemical bond properties of (La1-xMx)2CuO4(M=Ba, Sr) were calcu-lated . The calculated covalencies for Cu-O and La-O bond in the compounds are 0.3 and 0.03 respectively. Mossbauerisomer shifts of 57Fe doped in La2CuO4 and 119Sn doped in La2CuO4 were calculated by using the chemical surroundingfactor defined by covalency and electronic polarizability. Four valence state tin and three valence iron sites were identifiedin 57Fe and 119Sn doped La2CuO4.

关键词： superconductor rare earth oxide chemical bond Mossbauer effect