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Enhanced Ion Sampling Techniques for In-situ Neutral Gas and Low-energy Ions Exploration of Main-belt Comet
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作者 WANG Xinyue ZHANG Aibing +4 位作者 SU Bin DU Dan KONG Linggao TIAN Zheng ZHENG Xiangzhi 《空间科学学报》 北大核心 2025年第3期749-760,共12页
One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object... One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water. 展开更多
关键词 neutral gas low energy ions sampling techniques ion sampling techniques investigate space environment main belt comet gas ion analyzer gia situ measurement
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Progress of Radiation Belt Exploration by a Constellation of Small Satellites TGCSS/SGRB, COSPAR
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作者 WU Ji YANG Xiaochao +1 位作者 DAI Lei DENG Li 《空间科学学报》 CAS CSCD 北大核心 2024年第4期746-750,共5页
A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.To address the open qustions about the dynamics of the Earth’s radiation belt,CORBES mission... A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.To address the open qustions about the dynamics of the Earth’s radiation belt,CORBES mission would use a constellation of small/CubeSats to take an ultra-fast survey of the Earth’s radiation belt.The concept,science objectives and preliminary technical design of CORBES are introduced.This mission is an international multilateral cooperation mission coordinated by COSPAR.The SGRB Science Activities and COSPAR HQs Coordinate Activities on CORBES are summaried. 展开更多
关键词 Radiation belts Ultra-fast survey CONSTELLATION
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BELT装置硬质合金顶锤的有限元分析 被引量:7
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作者 王强 蔡冬梅 《机械设计》 CSCD 北大核心 2004年第6期13-15,共3页
建立了人造金刚石BELT合成装置硬质合金顶锤的有限元分析模型。采用耦合分析方法 ,综合考虑合成压力、径向预紧力和热应力的作用 ,获得了顶锤内部的应力场 ,阐述了破坏机理。对径向预紧力的作用和最佳数值进行了分析。通过分析顶锤半锥... 建立了人造金刚石BELT合成装置硬质合金顶锤的有限元分析模型。采用耦合分析方法 ,综合考虑合成压力、径向预紧力和热应力的作用 ,获得了顶锤内部的应力场 ,阐述了破坏机理。对径向预紧力的作用和最佳数值进行了分析。通过分析顶锤半锥角、高径比等参数对应力分布的影响 ,提出了结构优化的方法。 展开更多
关键词 belt装置 顶锤 硬质合金 有限元
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Retraction control of motorized seat belt system with linear state observer 被引量:3
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作者 LEE Kang-seok CHOI Chin-chul LEE Woo-taik 《Journal of Central South University》 SCIE EI CAS 2013年第2期385-392,共8页
A design and verification of linear state observers which estimate state information such as angular velocity and load torque for retraction control of the motorized seat belt (MSB) system were described. The motorize... A design and verification of linear state observers which estimate state information such as angular velocity and load torque for retraction control of the motorized seat belt (MSB) system were described. The motorized seat belt system provides functions to protect passengers and improve passenger's convenience. Each MSB function has its own required belt tension which is determined by the function's purpose. To realize the MSB functions, state information, such as seat belt winding velocity and seat belt tension are required. Using a linear state observer, the state information for MSB operations can be estimated without sensors. To design the linear state observer, the motorized seat belt system is analyzed and represented as a state space model which contains load torque as an augmented state. Based on the state space model, a linear state observer was designed and verified by experiments. Also, the retraction control of the MSB algorithm using linear state observer was designed and verified on the test bench. With the designed retraction control algorithm using the linear state observer, it is possible to realize various types of MSB functions. 展开更多
关键词 motorized seat belt system motorized seat belt (MSB) system linear state observer state space model augmented state retraction control
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叶膜石在Belt装置中的力学及热学行为 被引量:2
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作者 王强 《金属成形工艺》 北大核心 1993年第1期42-46,共5页
采用塑性理论,推导出叶腊石在人造金刚石Belt合成装置中所受径向约束力的计算公式,得出工艺参数对压力衰减率的影响规律,计算结果与实际情况相符。利用传热学理论,得出叶腊石合成试样的表面温度场。上述结果可为Belt装置的有限元分... 采用塑性理论,推导出叶腊石在人造金刚石Belt合成装置中所受径向约束力的计算公式,得出工艺参数对压力衰减率的影响规律,计算结果与实际情况相符。利用传热学理论,得出叶腊石合成试样的表面温度场。上述结果可为Belt装置的有限元分析提供依据。 展开更多
关键词 叶蜡石 belt装置 力学 热学
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Application Index of Enviromental Engineering by Using Carrier of Waste Material for Belt Seeding Establishment 被引量:1
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作者 DUOLi-an LIWen-hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第1期50-57,共8页
According to the principle of belt seeding establishment of adhesive bonded fabric,applied indexes of belt seeding establishment effect were studied using carrier combination of several kinds of waste meterials under... According to the principle of belt seeding establishment of adhesive bonded fabric,applied indexes of belt seeding establishment effect were studied using carrier combination of several kinds of waste meterials under soil cover.The results showed that the effect depended on the coordinated characteristics of carrier combination from turfgrass and waste materials.It was testified that production of belt seeding was feasible using a certain kind of waste material carrier under given conditions.The study provided a scientific basis for applying evvironmental engineering to belt seeding establishment of waste materials and developing nwe industry of environmental protection. 展开更多
关键词 TURFGRASS waste material belt seeding belt seeding establishment environmental engineering
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DEFINITING AND ITS GEOLOGIC MEANING OF SOUTH-NORTH TREND FAULTED STRUCTURE BELT IN QIANGTANG BASIN, NORTH PART OF TIBET 被引量:7
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作者 Liu Chiyang,Yang Xingke,Ren Zhangli,Wang Dingyi,Cheng Gang,Zheng Menlin 《地学前缘》 EI CAS CSCD 2000年第S1期223-224,共2页
There were more expounding to north—west (west) trend fault and north\|east trend fault within Qiangtang Basin, North Part of Tibet, in the past literature. With increasing of geophysical exploration data, nearly eas... There were more expounding to north—west (west) trend fault and north\|east trend fault within Qiangtang Basin, North Part of Tibet, in the past literature. With increasing of geophysical exploration data, nearly east\|west trend structure began to be taken note to. Since the year of 1995, by a synthetic study to geophysical and geological data, that south\|north trend faulted structures are well developed. These structures should be paid much more attention to, because they have important theoretical meaning and practical significance.1 Spreading of south\|north faulted structure belt According to different geological and geophysical data, the six larger scale nearly south\|north faulted structure belt could be distinguished within the scope of east longitude 84°~96° and near Qiangtang Basin. The actual location of the six belts are nearly located in the west of the six meridian of east longitude 85°,87°,89°,91°,93°,95° or located near these meridian. The six south\|north faulted structure belts spread in the same interval with near 2° longitude interval. The more clear and much more significance of south\|north trend faulted structure belts are the two S—N trend faulted structure belts of east longitude 87° and 89°. There are S—N trend faulted structure belts in the west of east longitude 83°,81°, or near the longitudes. The structure belts spreading features,manifestation,geological function and its importance, and inter texture and structure are not exactly so same. The structure belts all different degree caused different region of geological structure or gravity field and magnetic field. There is different scale near S—N trend faulted structure belt between the belts. 展开更多
关键词 Qinghai—Tibet plateau QIANGTANG Basin south—north TREND STRUCTURE belt transverse transform STRUCTURE strike\|slip adjustment division of east—west region oil & gas prospecting
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Numerical simulation and disaster prevention for catastrophic fire airflow of main air-intake belt roadway in coal mine—A case study 被引量:9
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作者 周刚 程卫民 +4 位作者 张睿 沈宝堂 聂文 张磊 王昊 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2359-2368,共10页
Coal mine belt fire develops very rapidly and is difficult to control. If not suppressed quickly, a belt fire could easily lead to airflow disorder and undermine the ventilation system. However, belt fire can be preve... Coal mine belt fire develops very rapidly and is difficult to control. If not suppressed quickly, a belt fire could easily lead to airflow disorder and undermine the ventilation system. However, belt fire can be prevented effectively by establishing fire airflow control system. In this work, the 5th belt roadway of Kongzhuang coal mine was taken as the object of investigation, where geometrical models of this roadway were established firstly. Then, based on mathematical model of fire smoke flow, the CO volume fraction, smoke density distribution, air temperature and pollutant velocity vector in the roadway before and after taking airflow control measures were simulated by using Fluent software. It can be known from the simulation that with the normal ventilation status in 5th belt roadway, the countercurrent of smoke does not happen when a fire occurs; the roadway's section is almost filled with CO at 10 m downstream from the fire source, and with air velocity getting stable gradually, the CO concentration reaches about 15 %. After taking airflow control measures, the effect range of temperature field which are harmful to the miners decreases from 69 m to 30 m; and the distance of the roadway fully filled with CO is 5 m farther than that before taking measures. Finally, according to the numerical simulation results and the actual condition of the belt roadway, the warning and automatic remote airflow control system with short-circuit method for the 5th belt roadway was designed to guarantee the safety production. 展开更多
关键词 belt roadway fire catastrophic airf ow numerical simulation flow pattern early warning and control
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A DEEP SEISMIC REFLECTION PROFILE ACROSS ALTUN FAULT BELT 被引量:3
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作者 Gao Rui 1, Liu Hongbin 2, Li Qiusheng 1,Li Pengwu 1, Yao Peiyi 1, Huang Dongding 3 (1 Lithosphere Research Center, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China,E\|mail: gaorui@cags.cn.net 2 Institute of Ge 《地学前缘》 EI CAS CSCD 2000年第S1期205-205,共1页
Altun fault is regarded as a large\|scale sinistral strike\|slip fault, it is composed of several faults with the different character, and there is a special geological structure in the fault belt, and they constitute... Altun fault is regarded as a large\|scale sinistral strike\|slip fault, it is composed of several faults with the different character, and there is a special geological structure in the fault belt, and they constitute the northwestern margin fault belt of the Qinghai\|Tibetan plateau. In order to investigate the deep crust structure in the Altun region, layers which Tarim lithosphere subducted beneath the Qinghai\|Tibetan plateau, the forward structure of the subduction plate and the scale of the plate subduction, a deep seismic reflection profile was designed. Data collection work of the deep seismic reflection profile across Altun fault was completed during 24/8/1999 to 25/9/1999. The profile locates in Qiemo county, Xinjiang Uygur Autonomous Region, the southern end of the profile stretches into Altun Mountains, the northern end locates in the Tarim desert margin. The profile is nearly SN trending and crosses the main Altun fault. The profile totally is 145km long, time record is 30 seconds, the smallest explosive amount is 72~100kg, the biggest explosive amount reaches 200~300kg, the explosive distance is 800m, and detectors are laid at a 50m distance. 展开更多
关键词 DEEP seismic reflection probing Altun FAULT belt TARIM b lock DEEP CRUST structure MOHO
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Mineralization-related geochemical anomalies derived from stream sediment geochemical data using multifractal analysis in Pangxidong area of Qinzhou-Hangzhou tectonic joint belt, Guangdong Province, China 被引量:5
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作者 张焱 周永章 +8 位作者 王林峰 王正海 何俊国 安燕飞 李红中 曾长育 梁锦 吕文超 高乐 《Journal of Central South University》 SCIE EI CAS 2013年第1期184-192,共9页
Distinguishing geochemical anomalies from background is a basic task in exploratory geochemistry. The derivation of geochemical anomalies from stream sediment geochemical data and the decomposition of these anomalies ... Distinguishing geochemical anomalies from background is a basic task in exploratory geochemistry. The derivation of geochemical anomalies from stream sediment geochemical data and the decomposition of these anomalies into their component patterns were described. A set of stream sediment geochemical data was obtained for 1 880 km 2 of the Pangxidong area, which is in the southern part of the recently recognized Qinzhou-Hangzhou joint tectonic belt. This belt crosses southern China and tends to the northwest (NE) direction. The total number of collected samples was 7 236, and the concentrations of Ag, Au, Cu, As, Pb and Zn were measured for each sample. The spatial combination distribution law of geochemical elements and principal component analysis (PCA) were used to construct combination models for the identification of combinations of geochemical anomalies. Spectrum-area (S-A) fractal modeling was used to strengthen weak anomalies and separate them from the background. Composite anomaly modeling was combined with fractal filtering techniques to process and analyze the geochemical data. The raster maps of Au, Ag, Cu, As, Pb and Zn were obtained by the multifractal inverse distance weighted (MIDW) method. PCA was used to combine the Au, Ag, Cu, As, Pb, and Zn concentration values. The S-A fractal method was used to decompose the first component pattern achieved by the PCA. The results show that combination anomalies from a combination of variables coincide with the known mineralization of the study area. Although the combination anomalies cannot reflect local anomalies closely enough, high-anomaly areas indicate good sites for further exploration for unknown deposits. On this basis, anomaly and background separation from combination anomalies using fractal filtering techniques can provide guidance for later work. 展开更多
关键词 geochemical anomalies fractal modeling principal component analysis Qinzhou-Hangzhou joint tectonic belt streamsediments
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Marc有限元在Belt型两面顶模具应力分析中的应用 被引量:2
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作者 王鹏 王强 +1 位作者 蔡冬梅 来小丽 《人工晶体学报》 EI CAS CSCD 北大核心 2008年第1期162-166,共5页
本文简要介绍了用于合成高品级金刚石工艺的Belt型两面顶装置的恶劣工作环境,以及模具的发展研究状况和相关技术瓶颈。简明概述了Marc软件强大的分析功能、程序结构特点以及接触问题的基本求解流程。以某一型号两面顶模具为例,利用Marc... 本文简要介绍了用于合成高品级金刚石工艺的Belt型两面顶装置的恶劣工作环境,以及模具的发展研究状况和相关技术瓶颈。简明概述了Marc软件强大的分析功能、程序结构特点以及接触问题的基本求解流程。以某一型号两面顶模具为例,利用Marc软件对其进行了建模计算,得到了模具的预应力分布,并采用Lame公式对计算结果进行了理论验证。 展开更多
关键词 有限元分析 两面顶模具 预应力环 应力分布 人造金刚石
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Ray Structure of the Coronal Streamer Belt and Its Manifestation as Sharp Large Peaks of Solar Wind Plasma Density at the Earth's Orbit 被引量:2
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作者 M. V. Eselevich V. G. Eselevich Z. Q. Zang 《空间科学学报》 CAS CSCD 北大核心 2005年第5期321-328,共8页
The white-light corona calibrated data with processing level L1 from the LASCO-C2/SOHO instrument, and data from the Wind spacecraft with one-hour and one-minute time resolution on quasi-stationary slow (v between 300... The white-light corona calibrated data with processing level L1 from the LASCO-C2/SOHO instrument, and data from the Wind spacecraft with one-hour and one-minute time resolution on quasi-stationary slow (v between 300-450 km/s at the Earth's orbit) the Solar Wind (SW) parameters in the absence of sporadic SW streams are examined. Within distances from the Sun's center less than R in the range of 20-30 Rs,(Rs, the solar radius), slow wind is known as the streamer belt, and at larger distances it is called the Heliospheric Plasma Sheet (HPS). It is shown that the streamer belt comprises a sequence of pairs of rays. In general, ray brightnesses in each pair can differ, and the magnetic field is oppositely directed in them. The neutral line of the radial magnetic field of the Sun runs along the belt between the rays of each of the pairs.The area in which the streamer belt intersects the ecliptic plane and which lies at the central meridian, will be recorded at the earth's orbit with a time delay of 5-6 days, in the form of one or several peaks with Nmax > 10 cm-3. Furthermore, the simplest density profile of the portion of the HCS has the form of two peaks of a different or identical amplitude . The such a profile is observed in cases where the angle of intersection of the streamer belt with the ecliptic plane near the Sun is sufficiently large, i.e. close to 90°. The two-ray structure of the cross-section of the streamer-belt moves from the Sun to the Earth, it retains not only the angular size of the peaks but also the relative density variations, and the position of the neutral line(sector boundary) in between. At the Earth's orbit the ray structure of the streamer belt provides the source for sharp (i.e. with steep fronts of a duration of a few minutes or shorter) solar wind plasma density peaks (of a duration of several hours) with maximum values Nmax > 10 cm-3. 展开更多
关键词 CORONA Solar wind Streamer belt
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Strategies for Promoting Cross-Cultural Communication under the“Belt and Road”Initiative 被引量:2
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作者 Zhang Yan 《学术界》 CSSCI 北大核心 2020年第4期221-231,共11页
The“Belt and Road”initiative is of great importance to the development of China and the great rejuvenation of the Chinese nation.Improving the cultural exchange between countries along the“Belt and Road”is vital t... The“Belt and Road”initiative is of great importance to the development of China and the great rejuvenation of the Chinese nation.Improving the cultural exchange between countries along the“Belt and Road”is vital to its success.It can be achieved by facilitating public diplomacy,spreading of the Silk Road spirit and promoting contacts among the peoples. 展开更多
关键词 the“belt and Road”initiative CHINESE CULTURE CROSS-CULTURAL COMMUNICATION
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A comparative study on the performances of synthetic diamond made by belt press & cubic press 被引量:1
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作者 Jia Pan~1,Lu Canhua~1,Ye Hongyu~2,Li Zhihong~3 (1.Nanyang Zhongnan Diamond Co.,Ltd.Nanyang,China) (2.Wuhan Wanbang Laser Diamond Tools Co.,Wuhan,China) (3.Industrial Diamond Association of China,Zhengzhou 450013,China ) 《金刚石与磨料磨具工程》 CAS 北大核心 2008年第S1期50-55,共6页
There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that ma... There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt press.With the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more objectively.Studies were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/40.Comparisons were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and arealight.And the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this paper.The report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made. 展开更多
关键词 COMPARATIVE study performance synthetic DIAMOND belt press cubic PRESS
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Belt型两面顶模具温度场和应力场有限元分析及钢带缠绕数值模拟初探 被引量:1
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作者 王鹏 王强 +1 位作者 蔡冬梅 来小丽 《人工晶体学报》 EI CAS CSCD 北大核心 2008年第2期493-499,共7页
在人造金刚石合成工艺中,两面顶模具合成腔体内的压力和温度起着至关重要的作用。根据对叶蜡石力学和热学行为的研究,基于MSC.Marc非线性有限元软件,建立了压缸温度场和应立场的有限元模型,模型中考虑了热导率等物理参数随温度的变化规... 在人造金刚石合成工艺中,两面顶模具合成腔体内的压力和温度起着至关重要的作用。根据对叶蜡石力学和热学行为的研究,基于MSC.Marc非线性有限元软件,建立了压缸温度场和应立场的有限元模型,模型中考虑了热导率等物理参数随温度的变化规律。采用FORTRAN语言开发了适用于温度和压力边界条件加载的相应程序,获得了合成状态下压缸的温度场和应力场分布情况。由温度梯度引起的热应力数值较小,对压缸所产生的影响程度较小。压缸内壁径向应力达到5GPa,接近硬质合金极限抗压强度。轴向应力最大值1GPa,出现在压缸外壁中心处。同时还建立了钢带缠绕模具其动态缠绕过程的简化模型,采用一种修正的库仑摩擦边界条件,模拟了钢带的缠绕过程,获得了钢带缠绕层间的应力、应变分布情况。 展开更多
关键词 有限元分析 两面顶模具 温度场 应力场 钢带缠绕 人造金刚石
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Research on the Transmission Paths of National Culture from the Perspective of the Belt and Road 被引量:1
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作者 Chen Bowang Su Xiaoli 《学术界》 CSSCI 北大核心 2019年第12期204-211,共8页
The Belt and Road initiative has promoted the connotative development and export of Chinese culture.To ensure a good international display and going globally of Chinese culture,we could follow such paths as excavating... The Belt and Road initiative has promoted the connotative development and export of Chinese culture.To ensure a good international display and going globally of Chinese culture,we could follow such paths as excavating the rich elements of traditional Chinese culture,shaping the fine works,creating culture brands with Chinese characteristics,developing new culture brands,opening up the cultural market,strengthening cultural dialogue,innovating cultural transmission paths by gathering the cultural forces at home and abroad,and enhancing the appeal of national culture so as to increase the closeness and recognition of people along the route. 展开更多
关键词 the belt and Road national culture transmission paths
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Forming Proterozoic basement within eastern Central Asian Orogenic Belt:Evidence from zircon U-Pb-Hf-O isotopes 被引量:1
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作者 WANG Zhi-wei ZHU Tai-chang +1 位作者 YU Jing-wen YUAN Ling-ling 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第9期3088-3105,共18页
As part of the mosaic of micro-continents within the Central Asian Orogenic Belt(CAOB), the Xing’anAirgin Sum Block(XAB) features increasingly-recognized Meso-Neoproterozoic geological records. However, the origin, t... As part of the mosaic of micro-continents within the Central Asian Orogenic Belt(CAOB), the Xing’anAirgin Sum Block(XAB) features increasingly-recognized Meso-Neoproterozoic geological records. However, the origin, temporal-spatial distribution of ancient materials, and their roles in crust evolution remain to debate. This paper presents an integrated study of zircon U-Pb ages and Hf-O isotopes for Mesoproterozoic and Paleozoic granites from the Erenhot region of central Inner Mongolia, along eastern CAOB. The intrusion of 1450 Ma syenogranite denotes that the Precambrian basement of XAB extends from Sonid Zuoqi westward to Erenhot. The 384 and 281 Ma monzogranites containing Mesoproterozoic xenocrystic zircons possess Proterozoic-dominant two-stage Hf model ages, further suggesting the wide existence of Proterozoic crust beneath western XAB. Cyclic Proterozoic crustal growth and reworking seem to show close linkages with the orogenesis during relevant supercontinent cycles. 1450-1360 Ma juvenile crustal growth at Erenhot and synchronous ancient crust reworking at Sonid Zuoqi and Abagaqi were likely resulted from retreating subduction involved in Columbia breakup, while 1.2-1.0 Ga reworking and 0.9-0.7 Ga growth events within the Erenhot basement might respond to assembly and breakup of Rodinia, respectively. Besides, our work confirms that reworking of Neoproterozoic crust played important roles during Paleozoic multi-stage accretion of CAOB. 展开更多
关键词 PROTEROZOIC Central Asian Orogenic belt Xing’an-Airgin Sum Block crystalline basement GRANITOIDS zircon U-Pb-Hf-O isotopes
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Progress of Radiation Belt Exploration by a Constellation of Small Satellites TGCSS/SGRB,COSPAR 被引量:1
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作者 WU Ji YANG Xiaochao DAI Lei 《空间科学学报》 CAS CSCD 北大核心 2022年第4期836-840,共5页
A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.The CORBES mission is expected to have a constellation of 10-plus small/Cube Sats to take an ... A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.The CORBES mission is expected to have a constellation of 10-plus small/Cube Sats to take an ultra-fast survey of the Earth’s radiation belt.The general science goal for CORBES is to investigate two groups of physical processes related to the radiation belts:wave-particle interactions and radial transport.This mission is an international multilateral cooperation mission,an open and sharing data policy will be implemented.The data set of observations will be shared within the contributors of the constellation and the broad research community at large,then would be of great use for comprehensively understanding the dynamics of magnetospheric energetic populations and developing more standard models of the Earth’s radiation belts.Furthermore,from the application perspective,the ultra-fast survey of the radiation belt could serve as an important facility for monitoring space weather of the Earth as well. 展开更多
关键词 Radiation belts Ultra-fast survey CONSTELLATION
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Belt型超高压模具若干问题研究和降低金刚石生产成本的途径 被引量:10
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作者 姚裕成 《人工晶体学报》 EI CAS CSCD 1995年第2期166-171,共6页
本文研讨了提高Belt型模具寿命的若干关键技术。介绍了国外模具寿命、容积大小与金刚石生产成本的关系现状。指出了我国两面顶技术大幅度降低金刚石生产成本,提高模具寿命的途径。
关键词 金刚石 晶体生长 高压 模具 生产成本 晶体加工
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THRUST PACKAGES OF 1.68 Ga INDIAN SUPRA-CRUSTAL ROCKS IN THE MIOCENE SIWALIK BELT,CENTRAL NEPAL HIMALAYAS
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作者 Harutaka Sakai\+1,Yutaka Takigami\+2,B.N.Upreti\+3,D.P.Adhikary\+3 2.Kanto Gakuen University,Ohta\|shi,Gunma,373\|8515 Japan 3.Department of Geology,Tri\|Chan 《地学前缘》 EI CAS CSCD 2000年第S1期64-66,共3页
The Siwalik Belt is a frontal fold\|thrust belt of the Himalayas and composed of thick sequence of foreland basin sediments derived from the Himalayas during the last 15 to 17 million years.From this Miocene belt in t... The Siwalik Belt is a frontal fold\|thrust belt of the Himalayas and composed of thick sequence of foreland basin sediments derived from the Himalayas during the last 15 to 17 million years.From this Miocene belt in the central Nepal,we discovered exotic thrust packages of the Middle Proterozoic rocks,which has been regarded as the Siwalik Group or post\|collisional sediments correlatable with the Subathu or Murree Formation in India.The thrust belt,called the Bagmati Belt,is narrowly distributed in the Siwalik Belt,22km to the north of the Main Frontal Thrust (MFT or HFF) that is an active fault and considered to be the deformation front of the Himalayan orogen.The Main Boundary Thrust (MBT) which separates the Siwalik Belt from the Lesser Himalayan Belt runs 7km to the north of the thrust packages.Within the belt,tectonic slices of 400m to 1km in thickness are repeated three to five times due to thrusts,sandwiching a thin slice of the Siwalik beds.The thrust package consists of the pre\|Siwalik sedimetary rocks and sills of dolerite,and named as the Bagmati Group.The thickness is only about 800m due to tectonic repition by thrust,although the group has been considered to be a continuous sequence attaining 2200m in thickness.We divided the Bagmati Group into three formations,each of which shows an upward\|coarsening and thickening sequence of 200 to 350m in thickness.All sequence is composed of red\|brown orthoquartzite,pink quartzite,micaceous shale and thin sandstone interbed and rhythmite,mottled hematite and hematitic pisolite.We interpret that the Bagmati Group was deposited in shallow lacustrine and desert environments. 展开更多
关键词 THRUST package the Bagmati Group the Siwalik belt CENTRAL Nepal HIMALAYA
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