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Research on active arc-ignition technology as a possible residual-energy-release strategy in electromagnetic rail launch

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Plasma Science and Technology 2021年第8期23卷 167-174页

作者： Xiyuan CAI sai tan Junyong LU Xiao ZHANG Yun GUO National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033People's Republic of China

In order to solve the problem of the original residual energy release strategy being unsuitable for high-energy and fast-firing electromagnetic rail launch,this work has explored the applicability of active arc-ignition technology(AAT).The results obtained from the comparison of launching experiments show that AAT has no influence on the acceleration of the armature and is capable of quickly releasing the residual *** on the theory of magnetohydrodynamics,this work has also made numerical simulation of the muzzle arc,analyzed the influence of AAT on the muzzle arc flow field,electromagnetic(EM)field and temperature field,and evaluated the performance of AAT according to the projectile initial disturbance,the EM impact on guidance devices and the rail *** results show that AAT is now one of the most practicable strategies for residual energy release.

关键词： muzzle arc initial disturbance guidance device arc ablation backflow

Dielectric breakdown properties of Al-air mixtures

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Plasma Science and Technology 2021年第5期23卷 59-65页

作者： Xiyuan CAI Xiao ZHANG Junyong LU sai tan Yongsheng ZHANG Guanxiang ZHANG National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033People's Republic of China

In order to investigate the influence of aluminum vapor on the breakdown performance of air,this paper makes a study of the dielectric breakdown characteristics of Al-air mixture in the temperature range of 300-5000 K at atmospheric pressure.A Boltzmann analysis method is used to deal with the electron energy distribution function(EEDF),the reduced ionization coefficients(α/N),the reduced attachment coefficients(η/N)and the critical reduced breakdown strength((E/N)cr)so as to explore the influence of temperature and mixing ratio on the dielectric breakdown *** the temperature range of 300-2000 K,the property of the mixture is mainly determined by the mixing proportion of aluminum vapor because the composition of particles remains *** the temperature range of 2000-2500 K,the decomposition of Al2O_(2)leads to the increase of aluminum oxides and NO,and a rise in the percentage of highenergy electrons as well as the increment ofα/***,the joint action of O_(2)and NO makesη/N increase first and then decrease,and(E/N)crgoes down to a smaller temperature *** increase in the proportion of aluminum vapor causes(E/N)crto decrease in the low-temperature region and to increase in the high-temperature region,which will reduce the transition between these two temperature regions.

关键词： aluminum vapor arc discharges Boltzmann analysis dielectric properties electromagnetic rail launch muzzle arc

Comparisons of cloud detection among four satellite sensors on severe haze days in eastern China

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Atmospheric and Oceanic Science Letters 2018年第1期11卷 86-93页

作者： tan sai-Chun ZHANG Xiao WANG Hong CHEN Bin SHI Guang-Yu SHI Chong State Key Laboratory of Numerical Modeling of Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing China College of Earth Science University of Chinese Academy of Sciences Beijing China State Key Laboratory of Severe Weather/Institute of Atmospheric Composition Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing China Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

Satellite remote sensing is very important to obtain a variety of cloud properties. However, the data quality from satellites varies with different satellite characteristics. From December 2015 to January 2016, ground-based air quality index （AQI） data showed severe haze events occurred successively in eastern China, particularly in the Beijing-Tianjin-Hebei region. During those days, a red alert （the most serious level）, orange alert （the second-highest level）, and yellow alert （the third-highest level） for haze, were issued in Beijing. Cloud detection from four sensors onboard the ＇A-Train＇satellite constellation were compared for two severe haze episodes, on 21 and 30 December 2015 respectively. Results showed that the MODIS sensor onboard the Aqua satellite misclassified aerosol as cloud, while the other three sensors-AIRS onboard Aqua, the cloud profiling radar onboard CloudSat, and CALIOP onboard CALIPSO-did not observe cloud over the same location. Through the high-AQI haze region in the CALIPSO and CloudSat orbit track, MODIS marked cloud close to the surface, while the MODIS true-color image and CALIOP observed an aerosol layer over the same location, suggesting MODIS falsely observed cloud there. Over the haze region in eastern China, MODIS observed 36% on average greater cloud fraction than AIRS, suggesting haze pollution induces a greater MODIS cloud amount.

关键词： Cloud detection aerosol haze MODIS AIRS CloudSat CALIPSO

Assessment of Dust Aerosol Optical Depth and Shortwave Radiative Forcing over the Northwest Pacific Ocean in Spring Based on Satellite Observations

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Atmospheric and Oceanic Science Letters 2009年第4期2卷 224-229页

作者： CHEN Lin SHI Guang-Yu ZHONG Ling-Zhi tan sai-Chun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical FluidDynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beo＇ing 100029 China Key laboratory of Radiometric Calibration and Validation for Environmental Satellites （KLRCV） National Satellite Meteorology Center China Meteorological Administration （SMC/CMA） Beijing 100081 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical ***,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product data in combination with Clouds and the Earth's Radiant Energy System Single Scanner Footprint (CERES/SSF) data,dust AOD and its shortwave RF were estimated over the cloud-free north-west (NW) Pacific Ocean in the springs of 2004,2005,and *** results showed that in this region,the mean dust AOD and its shortwave RF were 0.10 and 5.51 W m 2,*** order to validate the dust AOD de-rived by MODIS,results from the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model were also used *** correlation coefficient between the monthly averaged dust AOD derived by MODIS measurements and the model simulation results was approximately *** the estimates of the dust AOD and its shortwave RF obtained in this study are based mainly on satellite data,they offer a good reference for numerical models.

关键词： dust aerosols optical depth shortwave radia- tive forcing northwest Pacific satellite measurements

对外直接投资、逆向技术溢出与中国创新能力——基于中国与“一带一路”沿线不同类型国家的实证分析

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湖南科技大学学报（社会科学版） 2019年第3期22卷 60-66页

作者：谭赛湖南科技大学商学院湖南湘潭411201 湖南工程学院经济学院湖南湘潭411104

在国际R&D溢出理论的基础上,基于2003—2015年中国省际面板数据,分析对外直接投资促进创新能力的作用机制,实证检验中国对"一带一路"沿线国家直接投资的逆向技术溢出效应及其对我国创新能力的影响。研究结果表明,中国对"一带一路"沿线... 详细信息

在国际R&D溢出理论的基础上,基于2003—2015年中国省际面板数据,分析对外直接投资促进创新能力的作用机制,实证检验中国对"一带一路"沿线国家直接投资的逆向技术溢出效应及其对我国创新能力的影响。研究结果表明,中国对"一带一路"沿线国家直接投资的逆向技术溢出对国内创新能力提升具有显著的促进作用。进一步将沿线各国按照经济体类型分类后的研究结果显示,对"一带一路"沿线国家中发达经济体的直接投资带来的逆向技术创新效应明显大于转型与发展中经济体。在上述结论的基础上,从对外直接投资有利于创新能力和经济发展方面提出了相应的政策建议。

关键词：对外直接投资逆向技术溢出创新能力

Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： Yan-Heng Yu sai Wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

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宗教改革与近代早期伦敦葬礼的变迁

史学集刊 2008年第2期 115-121页

作者：谭赛花武汉大学历史学院湖北武汉430072

近代早期英国经历了曲折的宗教改革,大部分伦敦居民的死亡观念和葬礼实践随之发生了变化。在灵魂得救上,他们接受了"因信称义",摈弃了炼狱观念。在墓地的选择上,由于宗教改革缩小了教区墓地的面积,中间阶层与精英阶层争夺教区内最神圣... 详细信息

近代早期英国经历了曲折的宗教改革,大部分伦敦居民的死亡观念和葬礼实践随之发生了变化。在灵魂得救上,他们接受了"因信称义",摈弃了炼狱观念。在墓地的选择上,由于宗教改革缩小了教区墓地的面积,中间阶层与精英阶层争夺教区内最神圣的墓地——教堂,普通市民不得不葬入郊外新建的墓地。在葬礼仪式上,减少了许多天主教性质的仪式,世俗机构纹章院对葬礼的控制进一步加剧了葬礼仪式的世俗化。归根结底,新教的"入世禁欲"观念极大地推动了葬礼的变迁,同时,节俭、谋利的资本主义精神贯穿葬礼变迁之始终。

关键词：葬礼宗教改革近代早期伦敦资本主义精神

乡村振兴战略背景下农民专业合作社社员资格立法之检视

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中南大学学报（社会科学版） 2022年第2期28卷 106-115页

作者：张德峰谭赛湖南师范大学法学院湖南长沙410081

合作社社员资格指个体取得社员身份须满足的条件,包括积极资格与消极资格两种。从应然角度看,积极资格包括个体应具有对合作社的利用需求、具备互助合作的基本能力,消极资格包括个体不得损害合作社及其社员利益、不得损害第三人利益和... 详细信息

合作社社员资格指个体取得社员身份须满足的条件,包括积极资格与消极资格两种。从应然角度看,积极资格包括个体应具有对合作社的利用需求、具备互助合作的基本能力,消极资格包括个体不得损害合作社及其社员利益、不得损害第三人利益和社会公共利益。现行农民专业合作社立法在社员资格设置的内容与方式上均存在不足。为助推农民专业合作社健康发展,助力乡村振兴战略实施,有必要改进现行立法:在社员资格的设置内容上,明确社员利用农民专业合作社服务的具体形式、改变对“农民”的认定方式、放开对自然人社员民事行为能力条件和国籍条件的限制以及增设“不得损害第三人利益和社会公共利益”为消极资格的内容;在社员资格的设置方式上,明确社员资格主要由农民专业合作社及其社员设置。

关键词：乡村振兴战略合作社社员资格农民专业合作社法

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海洋初级生产力的卫星遥感

地球科学进展 2005年第8期20卷 863-870页

作者：檀赛春石广玉中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室

从海水的光学特性入手,依据卫星探测海洋初级生产力的基本原理,详细讨论了大气校正过程,并较为全面地阐述了现有的一些海洋初级生产力模式。通过列举个例对这些模式进行分类讨论,并对模式应用中的一些问题作出了分析和讨论,在此基础上... 详细信息

从海水的光学特性入手,依据卫星探测海洋初级生产力的基本原理,详细讨论了大气校正过程,并较为全面地阐述了现有的一些海洋初级生产力模式。通过列举个例对这些模式进行分类讨论,并对模式应用中的一些问题作出了分析和讨论,在此基础上指出了其存在的问题和发展的方向。

关键词：海洋初级生产力光学特性大气校正初级生产力模式