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2013年岷县漳县M_(S)6.6地震和2017年九寨沟M_(S)7.0地震震前地球物理观测异常空间分布机理分析 被引量:1
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作者 杨晨艺 石富强 +4 位作者 季灵运 杨宜海 苏利娜 杨敏 郑怡 《地震学报》 CSCD 北大核心 2024年第2期307-326,共20页
对甘东南地区2013年岷县漳县M_(S)6.6地震和2017年九寨沟M_(S)7.0地震震前地球物理观测异常特征进行总结梳理。根据活动构造单元对地球物理观测台站进行区域划分,统计了相关构造单元上异常的数量和百分比,以及不同学科震前异常数量、百... 对甘东南地区2013年岷县漳县M_(S)6.6地震和2017年九寨沟M_(S)7.0地震震前地球物理观测异常特征进行总结梳理。根据活动构造单元对地球物理观测台站进行区域划分,统计了相关构造单元上异常的数量和百分比,以及不同学科震前异常数量、百分比、异常持续时间等特征,并对异常的空间分布和机理进行分析,讨论了活动构造对异常分布的影响、异常强度与震源机制及断层应力之间的关系。结果表明:①2013年岷县漳县M_(S)6.6地震比2017年九寨沟M_(S)7.0地震震前地球物理观测异常百分比高,两次地震的震前电磁异常和跨断层水准测量异常均较为显著,而流体异常不明显;②震前地球物理观测异常分布与活动构造相关,2013年岷县漳县M_(S)6.6地震震前异常主要集中在东昆仑-西秦岭断裂带和六盘山-海原断裂带,2017年九寨沟M_(S)7.0地震震前异常则主要集中在龙门山断裂带和东昆仑-西秦岭断裂带;③两次地震震前地球物理观测异常分布均与GNSS速度场分布特征有较好的对应关系;④安德森断层应力模式解释了2013年岷县漳县M_(S)6.6地震(逆冲型)比2017年九寨沟M_(S)7.0地震(走滑型)的形成需要更多的应力积累,因此2013年岷县漳县M_(S)6.6地震虽然震级较小但震前异常更显著。 展开更多
关键词 2013年岷县漳县MS6.6地震 2017年九寨沟MS7.0地震 观测异常 地震预测
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基于潮汐附加构造应力的2013年灯塔M_(S)5.1地震射出长波辐射变化分析
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作者 荆涛 Boonphor Phetphouthongdy +4 位作者 Chansouk Sioudom 刘洋洋 李继庚 康春丽 马未宇 《地震》 CSCD 北大核心 2024年第2期52-62,共11页
针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月1... 针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月15日)的ATSCTF变化。地震发生时,ATSCTF垂直方向分量处于高相位点附近,显示引潮力对本次正断层走滑型地震具有诱发作用。以ATSCTF变化周期的各低相位点时间(2012年12月19日、2013年1月4日、2013年1月18日、2013年2月2日)数据分别为背景,各周期期后数据分别与背景逐日相减,计算研究区(36°N~46°N,118°E~128°E)范围内,National Oceanic and Atmospheric Administration(NOAA)卫星射出长波辐射数据(Outgoing Long Wave Radiation,OLR)在各ATSCTF周期时段分布及其变化。结果显示,无震的ATSCTF变化的A、B、D周期,震中附近OLR无变化;发震的ATSCTF变化的C周期,在空间上,该地区震前OLR仅震中及其南侧区域发生了显著连续升高变化过程,在时间上经历了初始微异常→异常加强→高峰→衰减→发震→平静的演化过程,与岩石应力加载—破裂经历:初始微动破裂→扩张破裂→应力闭锁→地震爆发→平静的力学演化过程中各阶段红外辐射特征一致;显示引潮力对处于临界状态的活动断层具有诱发作用,而OLR是地震构造应力应变过程辐射表征。 展开更多
关键词 2013年灯塔M_(S)5.1地震 长波辐射 潮汐附加构造应力 震前ATSCTF周期异常
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Experimental research on the launching system of auxiliary charge with filter cartridge structure
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作者 Zi-Jun Chen Ze He +2 位作者 Hong-Hao Ma Lu-Qing Wang Zhao-Wu Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期41-48,共8页
A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in th... A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the barrel.The breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the projectile.In this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the projectile.The proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the chamber.In order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are discussed.The experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak pressure.The projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,respectively.The muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the barrel.Under the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%. 展开更多
关键词 Interior ballistics Charge structures launch system Charge design
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Study on the coupling calculation method for the launch dynamics of a self-propelled artillery multibody system considering engraving process
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作者 Shujun Zhang Xiaoting Rui +1 位作者 Hailong Yu Xiaoli Dong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期67-85,共19页
The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational eff... The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational efficiency,and imprecise analyses of system dynamic responses found in the dynamics research of intricate multi-rigid-flexible body systems,such as self-propelled artillery.This advancement aims to enhance the firing accuracy and launch safety of self-propelled artillery.Recognizing the shortfall of overlooking the band engraving process in existing theories,this study introduces a novel coupling calculation methodology for the launch dynamics of a self-propelled artillery multibody system.This method leverages the ABAQUS subroutine interface VUAMP to compute the dynamic response of the projectile and barrel during the launch process of large-caliber self-propelled artillery.Additionally,it examines the changes in projectile resistance and band deformation in relation to projectile motion throughout the band engraving process.Comparative analysis of the computational outcomes with experimental data evidences that the proposed method offers a more precise depiction of the launch process of self-propelled artillery,thereby enhancing the accuracy of launch dynamics calculations for self-propelled artillery. 展开更多
关键词 Self-propelled artillery Engraving process Multibody system dynamics launch dynamics
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A CombustionModel for Explosive Charge Affected by a Bottom Gap in the Launch Environment
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作者 ShiboWu Weidong Chen +4 位作者 Jingxin Ma Lan Liu Shengzhuo Lu Honglin Meng Xiquan Song 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1207-1236,共30页
Launch safety of explosive charges has become an urgent problem to be solved by all countries in the world aslaunch situation of ammunition becomes consistentlyworse.However, the existing numericalmodels have differen... Launch safety of explosive charges has become an urgent problem to be solved by all countries in the world aslaunch situation of ammunition becomes consistentlyworse.However, the existing numericalmodels have differentdefects. This paper formulates an efficient computational model of the combustion of an explosive charge affectedby a bottom gap in the launch environment in the context of the material point method. The current temperatureis computed accurately from the heat balance equation, and different physical states of the explosive charges areconsidered through various equations of state. Microcracks in the explosive charges are described with respectto the viscoelastic statistical crackmechanics (Visco–SCRAM) model. Themethod for calculating the temperatureat the bottomof the explosive charge with respect to the bottomgap is described. Based on this combustionmodel,the temperature history of a Composition B (COMB) explosive charge in the presence of a bottom gap is obtainedduring the launch process of a 155-mm artillery. The simulation results show that the bottom gap thickness shouldbe no greater than 0.039 cm to ensure the safety of the COM B explosive charge in the launch environment. Thisconclusion is consistent with previous results and verifies the correctness of the proposed model. Ultimately, thispaper derives amathematical expression for themaximumtemperature of the COMB explosive chargewith respectto the bottomgap thickness (over the range of 0.00–0.039 cm), and establishes a quantitative evaluationmethod forthe launch safety of explosive charges.The research results provide some guidance for the assessment and detectionof explosive charge safety in complex launch environments. 展开更多
关键词 Combustion model explosive charge safety launch environment bottom gap TEMPERATURE
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A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory
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作者 Yunfei Miao Guoping Wang Wei Tian 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期232-241,共10页
How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS consi... How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS considering the credibility of simulation system based on Bayesian theory is proposed in this paper.First of all,a comprehensive index system for the credibility of the simulation system of the firing precision of the MLRS is constructed combined with the group analytic hierarchy process.A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight coefficients.The Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution,and the rationality of prior information used in estimation model is discussed quantitatively.With the simulation tests,the different evaluation methods are compared to validate the effectiveness of the proposed method.Finally,the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%. 展开更多
关键词 Multiple launch rocket system Bayesian theory Simulation credibility Mixed prior distribution Firing precision
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Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle
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作者 ZHANG Guo-xing XIA Xin-lu GUO Jin-wei 《China Ocean Engineering》 SCIE EI CSCD 2024年第3期453-466,共14页
Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling ca... Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological features.Firstly,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain synthesis.Secondly,the screw theory is employed to analyze the degree of freedom(DoF)of the capture mechanism.Then,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried out.Combined with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried out.Furthermore,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are analyzed.Finally,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is completed.The work provides technical reserves for the research and development of AUV capture special equipment. 展开更多
关键词 capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis
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The Launch of IEA Report World Energy Investment 2024 Successfully Held
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作者 Yang Lei 《China Oil & Gas》 CAS 2024年第4期26-29,共4页
On July 18,2024,the Launch of IEA Report World Energy Investment Report 2024 was released at Peking University.This conference was co-hosted by the International Energy Agency(IEA)and the Institute of Energy,Peking Un... On July 18,2024,the Launch of IEA Report World Energy Investment Report 2024 was released at Peking University.This conference was co-hosted by the International Energy Agency(IEA)and the Institute of Energy,Peking University. 展开更多
关键词 IEA launch World
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Commercial Aerospace: The Next Launchpad For the Chinese Economy
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作者 Zhang Lijuan 《China Report ASEAN》 2024年第2期22-25,共4页
On December 29,2023,the first launch service tower was completed at the Hainan International Commercial Aerospace Launch Center,marking a key step forward in building the launch capacity of China’s first commercial a... On December 29,2023,the first launch service tower was completed at the Hainan International Commercial Aerospace Launch Center,marking a key step forward in building the launch capacity of China’s first commercial aerospace launch site.On December 10,a Hyperbola-2 methane-liquid oxygen reusable verification rocket was launched successfully,marking the first recovery of reusable carrier rockets in China. 展开更多
关键词 launch launch ROCKET
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2013—2022年横江中下游流域汛期面雨量特征分析
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作者 赵军学 何娟 +1 位作者 彭斌 晏翠玲 《现代农业科技》 2024年第12期138-143,149,共7页
本文利用2013—2022年横江中下游流域昭通段自动气象站汛期4—10月逐日20:00至次日20:00降水资料,采用泰森多边形法计算4个子流域逐日面雨量,并对其时空分布特征进行分析。结果表明:近10年横江中下游汛期降水时空变化特征明显,汛期年面... 本文利用2013—2022年横江中下游流域昭通段自动气象站汛期4—10月逐日20:00至次日20:00降水资料,采用泰森多边形法计算4个子流域逐日面雨量,并对其时空分布特征进行分析。结果表明:近10年横江中下游汛期降水时空变化特征明显,汛期年面雨量平均值为843.3 mm,降雨主要集中在5—9月,5月开始有强降水发生,8月最多;各个子流域汛期面雨量强降水频次平均值为2.4~5.2次,关河流域最易出现强降水,洒渔河流域最少,除洒渔河流域外,子流域均会出现日面雨量≥60 mm以上强降水,其中白水江流域强降水最大;出现流域性强降水频次为3.4次/a,白水江流域易与洛泽河流域或关河流域同时发生强降水,全流域性强降水的可能性不可忽视。 展开更多
关键词 横江流域 泰森多边形 面雨量 面雨量强降水 2013—2022年
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Trajectory Design and Flight Result of Gravity-1 Launch Vehicle
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作者 FAN Shaobing ZHANG Chi +3 位作者 ZHANG Jie XU Guoguang HUANG Shuai BU Xiangwei 《Aerospace China》 2024年第1期34-39,共6页
Gravity-1(YL-1) launch vehicle completed its maiden flight from the Yellow Sea near Haiyang City, Shandong Province, on January 11, 2024, this mission successfully launched three Yunyao satellites into their 500 km or... Gravity-1(YL-1) launch vehicle completed its maiden flight from the Yellow Sea near Haiyang City, Shandong Province, on January 11, 2024, this mission successfully launched three Yunyao satellites into their 500 km orbit. The YL-1 has a performance of 4.2 tons for 500 km sun-synchronous orbit and 6.5 tons for low Earth orbit. The success of YL-1 has further enriched China's launch vehicle spectrum, and will facilitate the launch of medium and large satellites and satellite constellations. In this paper, the flight ballistic solution of YL-1 is introduced. The flight trajectory consists of seven flight segments. The trajectory design comprehensively considered the characteristics and safety requirements of the vehicle to achieve effective utilization of the performance. Through comparative analysis of the flight trajectory and the predicted trajectory, the result confirmed that the flight trajectory was consistent with the design results, the design methodology was correct, and the flight test met the expected requirements. Subsequently, the vehicle will be employed for commercial application launch services. 展开更多
关键词 trajectory design Gravity-1 launch vehicle sea launch
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Technical Characteristics and Innovations of the Gravity-1 Launch Vehicle
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作者 HUANG Shuai BU Xiangwei +4 位作者 YU Jichao ZHAO Yeni XU Guoguang PENG Weibin WANG Yonggang 《Aerospace China》 2024年第1期3-8,共6页
On January 11, 2024, the Gravity-1 launch vehicle successfully carried out its maiden flight from a mobile sea platform off the coast of Haiyang in Shandong Province, sending three meteorological satellites, Yunyao-1 ... On January 11, 2024, the Gravity-1 launch vehicle successfully carried out its maiden flight from a mobile sea platform off the coast of Haiyang in Shandong Province, sending three meteorological satellites, Yunyao-1 satellite No. 18-20, into an orbit about 500 km above the ground. The successful debut flight of Gravity-1 broke many records such as the world's largest solid launch vehicle, the first sea-launched strap-on launch vehicle in the world, with the maximum carrying capacity of current commercial launch vehicle in China. This flight marked a big step in the field of China's commercial space launch application. A new breakthrough has been made, which is of great significance for further expanding China's diversified and large-scale launch capabilities of medium and low orbit satellites, expanding the spectrum of China's launch vehicle types, and promoting the development of space science. 展开更多
关键词 Gravity-1 all-solid strap-on launch vehicle sea launch
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论一镜到底喜剧电影表现特色——以三谷幸喜《大空港2013》与《人生小节》为例
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作者 刘珂珂 《戏剧之家》 2024年第27期144-146,共3页
日本新生代导演三谷幸喜作为喜剧电影世界里最具有辨识度的导演之一,以其一系列独具魅力的具有舞台剧特质的电影征服了无数影迷。他所创作的喜剧电影具有以下特点:由于戏剧出身而使其电影带有强烈的舞台设置感,人物偏向圆形的现实主义... 日本新生代导演三谷幸喜作为喜剧电影世界里最具有辨识度的导演之一,以其一系列独具魅力的具有舞台剧特质的电影征服了无数影迷。他所创作的喜剧电影具有以下特点:由于戏剧出身而使其电影带有强烈的舞台设置感,人物偏向圆形的现实主义小人物,长镜头的摄制与剪辑理念,以及对历史或科幻喜剧题材的大胆尝试等。本文以三谷幸喜的一镜到底喜剧片《大空港2013》与《人生小节》为例,从人物塑造和叙事结构的角度出发,研究其表现特色。 展开更多
关键词 三谷幸喜 一镜到底 《大空港2013 喜剧理念
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Analysis of the Gravity-1 Sea Launch System and Technical Features
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作者 ZHANG Tao HUANG Shuai +2 位作者 Ma Ma BU Xiangwei XU Guoguang 《Aerospace China》 2024年第1期18-27,共10页
Sea launch has the characteristics of flexible launching points, high landing area safety, and good economy. In recent years, it has become one of the important launch methods. Since 2019, China has carried out a tota... Sea launch has the characteristics of flexible launching points, high landing area safety, and good economy. In recent years, it has become one of the important launch methods. Since 2019, China has carried out a total of 11 successful sea launches. The Gravity-1(YL-1) sea launch system consists of a launch vehicle system and a sea launch platform. The sea launch program includes roll on/roll off boarding, sea mooring, sea maneuvering, anchoring and positioning, system testing, and formal launch. Through the maiden flight of YL-1, the design and manufacturing technology of large tonnage dedicated launch ship, launch vehicle vertical transfer and roll on/roll off boarding technology, anti-shake technology for sea launch, simple inflatable flexible insulation protective cover technology, and remote wireless measurement and control technology have been fully verified. 展开更多
关键词 YL-1 sea launch system technical features
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Introduction and Prospects of Gravity-1 Launch Vehicle’s Sea-Based Three Verticals Testing and Launch Mode
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作者 MA Ma BU Xiangwei +1 位作者 HUANG Shuai WANG Yonggang 《Aerospace China》 2024年第1期28-33,共6页
Gravity-1 was the world's first carrier rocket to adopt the sea-based “three vertical” testing launch mode. This article introduces the overall layout of the launch site and the workflow of rocket testing and la... Gravity-1 was the world's first carrier rocket to adopt the sea-based “three vertical” testing launch mode. This article introduces the overall layout of the launch site and the workflow of rocket testing and launch for its maiden flight mission. The process of vertical assembly, vertical testing, vertical transportation, and sea-based hot launches are explained. Additionally, it provides an outlook on the improved “three vertical” testing and launch mode for future missions, such as land-based launches, rapid launches, and remote sea launches. 展开更多
关键词 testing and launch mode overall layout vertical assembly vertical testing vertical transportation
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Seco News Launch2013新品发布在即
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《制造技术与机床》 北大核心 2013年第4期5-5,共1页
Seco News Launch自2010年秋季登陆中国以来,日益受到广大用户的喜爱。
关键词 “Seco NEWS launch2013” 新产品 商品展览 孔加工
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狂犬病毒GSQY-Dog-China-2013株全基因组序列测定和遗传进化分析
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作者 邢广旭 姜中毅 +2 位作者 焦文强 王方雨 张改平 《中国兽医杂志》 CAS 北大核心 2023年第1期8-13,共6页
为了全面分析我国狂犬病病毒遗传进化情况,本试验使用反转录PCR(RT-PCR)方法将狂犬病病毒GSQY-Dog-China-2013分为10个片段进行扩增,回收目的片段并与pMD20-T simple载体连接,转化JM109感受态细胞,挑取阳性克隆进行测序;使用DNASTAR软... 为了全面分析我国狂犬病病毒遗传进化情况,本试验使用反转录PCR(RT-PCR)方法将狂犬病病毒GSQY-Dog-China-2013分为10个片段进行扩增,回收目的片段并与pMD20-T simple载体连接,转化JM109感受态细胞,挑取阳性克隆进行测序;使用DNASTAR软件中的Edit Seq通过拼接相邻片段之间的重叠序列获得GSQY-Dog-China-2013全基因组序列,构建系统进化树进行遗传进化分析。结果显示,GSQY-Dog-China-2013全长11924核苷酸(nt),包含5个开放阅读框,分别编码核蛋白(N)、磷蛋白(P)、基质蛋白(M)、糖蛋白(G)和转录大蛋白(L);基于全基因组序列的进化树分析显示,GSQY-Dog-China-2013株和国内分离株形成一个分支,在国内分离株中与SXYL15株和SXBJ15株形成一个分支,亲缘关系最接近,提示GSQY-Dog-China-2013可能源自我国陕西省。本试验系甘肃省首次报道狂犬病病毒全基因组序列,进一步丰富了我国狂犬病病毒遗传进化数据,为狂犬病全面防治以及疫苗研发提供了数据支持。 展开更多
关键词 狂犬病病毒 GSQY-Dog-China-2013 全基因组序列测定 遗传进化分析
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大豆浙鲜豆2013的选育与栽培技术 被引量:1
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作者 郁晓敏 袁凤杰 +2 位作者 傅旭军 杨清华 金杭霞 《浙江农业科学》 2023年第7期1696-1698,共3页
浙鲜豆2013是浙江省农业科学院作物与核技术利用研究所采用常规杂交育种方法育成的鲜食春大豆新品种,2022年通过农业农村部国家农作物品种审定委员会审定,审定编号为国审豆20220052,具有丰产性较好、品质优等特点。生育期83 d,有限结荚... 浙鲜豆2013是浙江省农业科学院作物与核技术利用研究所采用常规杂交育种方法育成的鲜食春大豆新品种,2022年通过农业农村部国家农作物品种审定委员会审定,审定编号为国审豆20220052,具有丰产性较好、品质优等特点。生育期83 d,有限结荚习性,株高39.6 cm,主茎9.3节,有效分枝2.0个,单株有效荚数17.9个,多粒荚率66.2%,单株鲜荚重47.1 g,每500 g标准荚数158个,标准两粒荚荚长6.0 cm,荚宽1.4 cm,百粒鲜重81.7 g,籽粒扁圆形,种皮淡绿色、无光,种脐无色,子叶黄色,口感为香甜柔糯型。中抗花叶病毒病3号株系,中感花叶病毒病7号株系,感炭疽病。2019—2020年鲜食大豆春播组区域试验667 m^(2)平均产量830.6 kg,2021年生产试验667 m^(2)产量840.8 kg。 展开更多
关键词 浙鲜豆2013 鲜食大豆 特征特性 栽培技术
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国际中文教育研究的新特点与新趋势——基于2013-2022年国家社科基金立项的考察 被引量:1
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作者 赵雅文 励智 《四川师范大学学报(社会科学版)》 北大核心 2023年第2期133-140,共8页
2022年“国际中文教育”专业学位类别独立设置,开启了国际中文教育新篇章,也对该专业的科学研究提出了更高的要求。为了助力面向未来的国际中文教育研究高质量发展,笔者以2013-2022年国家社科基金立项作为研究对象,通过对立项年度、类... 2022年“国际中文教育”专业学位类别独立设置,开启了国际中文教育新篇章,也对该专业的科学研究提出了更高的要求。为了助力面向未来的国际中文教育研究高质量发展,笔者以2013-2022年国家社科基金立项作为研究对象,通过对立项年度、类型、学科、题目、成果、单位等数据统计的量化分析,提炼出目前国际中文教育研究内容兼顾学科与事业发展、研究领域体现多学科交叉融合、研究方法突出现代科技运用、研究群体多立足本校优势学科等四个新特点,并详细解析了国际中文教育内部外部研究并行发展、精准契合国家发展战略、实现深度交叉融合、广泛应用数字科技手段、参与研究群体覆盖面不断扩大的发展趋势。 展开更多
关键词 2013-2022年 国家社科基金立项 国际中文教育研究新特点 国际中文教育研究新趋势
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Watt Linkage–Based Legged Deployable Landing Mechanism for Reusable Launch Vehicle: Principle, Prototype Design, and Experimental Validation 被引量:1
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作者 Haitao Yu Baolin Tian +6 位作者 Zhen Yan Haibo Gao Hongjian Zhang Huiqiang Wu Yingchao Wang Yuhong Shi Zongquan Deng 《Engineering》 SCIE EI CAS CSCD 2023年第1期120-133,共14页
The reusable launch vehicle (RLV) presents a new avenue for reducing cost of space transportation. The landing mechanism, which provides landing support and impact absorption, is a vital component of the RLV at final ... The reusable launch vehicle (RLV) presents a new avenue for reducing cost of space transportation. The landing mechanism, which provides landing support and impact absorption, is a vital component of the RLV at final stage of recovery. This study proposes a novel legged deployable landing mechanism (LDLM) for RLV. The Watt-II six-bar mechanism is adopted to obtain the preferred configuration via the application of the linkage variation approach. To endow the proposed LDLM with advantages of large landing support region, lightweight, and reasonable linkage internal forces, a multi-objective optimization paradigm is developed. Furthermore, the optimal scale parameters for guiding the LDLM prototype design is obtained numerically using the non-dominated sorting genetic algorithm-II (NSGA-II) evolutionary algorithm. A fully-functional scaled RLV prototype is developed by integrating the gravity-governed deploying scheme to facilitate unfolding action to avoid full-range actuation, a dual-backup locking mechanism to enhance reliability of structure stiffening as fully deployed, and a shock absorber (SA) with multistage honeycomb to offer reliable shock absorbing performance. The experimental results demonstrate that the proposed LDLM is capable of providing rapid and smooth deployment (duration less than 1.5 s) with mild posture disturbance to the cabin (yaw and pitch fluctuations less than 6°). In addition, it provides satisfactory impact attenuation (acceleration peak less than 10g (g is the gravitational acceleration)) in the 0.2 m freefall test, which makes the proposed LDLM a potential alternative for developing future RLV archetype. 展开更多
关键词 Reusable launch vehicle(RLV) Deployable mechanism Optimization desi gn
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