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The Solar Upper Transition Region Imager(SUTRI)Onboard the SATech-01 Satellite 被引量:8
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作者 Xianyong Bai Hui Tian +56 位作者 Yuanyong Deng Zhanshan Wang Jianfeng Yang Xiaofeng Zhang Yonghe Zhang Runze Qi Nange Wang Yang Gao Jun Yu Chunling He Zhengxiang Shen Lun Shen Song Guo Zhenyong Hou Kaifan Ji Xingzi Bi Wei Duan Xiao Yang Jiaben Lin Ziyao Hu Qian Song Zihao Yang Yajie Chen Weidong Qiao Wei Ge Fu Li Lei Jin Jiawei He Xiaobo Chen Xiaocheng Zhu Junwang He Qi Shi Liu Liu Jinsong Li Dongxiao Xu Rui Liu Taijie Li Zhenggong Feng Yamin Wang Chengcheng Fan Shuo Liu Sifan Guo Zheng Sun Yuchuan Wu Haiyu Li Qi Yang Yuyang Ye Weichen Gu Jiali Wu Zhe Zhang Yue Yu Zeyi Ye Pengfeng Sheng Yifan Wang Wenbin Li Qiushi Huang Zhong Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期153-171,共19页
The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the... The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections. 展开更多
关键词 Sun:transition region Sun:UV radiation Sun:activity space vehicles:instruments
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Geological characteristics and accumulation mechanisms of the "continuous" tight gas reservoirs of the Xu2 Member in the middle-south transition region,Sichuan Basin,China 被引量:12
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作者 Zou Caineng Gong Yanjie +1 位作者 Tao Shizhen Liu Shaobo 《Petroleum Science》 SCIE CAS CSCD 2013年第2期171-182,共12页
"Continuous" tight gas reservoirs are those reservoirs which develop in widespread tight sandstones with a continuous distribution of natural gas. In this paper, we summarize the geological features of the source ro... "Continuous" tight gas reservoirs are those reservoirs which develop in widespread tight sandstones with a continuous distribution of natural gas. In this paper, we summarize the geological features of the source rocks and "'continuous" tight gas reservoirs in the Xujiahe Formation of the middle- south transition region, Sichuan Basin. The source rocks of the Xul Member and reservoir rocks of the Xu2 Member are thick (Xul Member: 40 m, Xu2 Member: 120 m) and are distributed continuously in this study area. The results of drilled wells show that the widespread sandstone reservoirs of the Xu2 Member are charged with natural gas. Therefore, the natural gas reservoirs of the Xu2 Member in the middle-south transition region are "continuous" tight gas reservoirs. The accumulation of "continuous" tight gas reservoirs is controlled by an adequate driving force of the pressure differences between source rocks and reservoirs, which is demonstrated by a "one-dimensional" physical simulation experiment. In this simulation, the natural gas of"continuous" tight gas reservoirs moves tbrward with no preferential petroleum migration pathways (PPMP), and the natural gas saturation of"continuous" tight gas reservoirs is higher than that of conventional reservoirs. 展开更多
关键词 Geological characteristics accumulation mechanism "continuous" tight gas reservoir Xu2Member middle-south transition region Sichuan Basin
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Analyzing Land-use Change in Farming-pastoral Transitional Region Using Autologistic Model and Household Survey Approach 被引量:3
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作者 ZHU Likai MENG Jijun MAO Xiyan 《Chinese Geographical Science》 SCIE CSCD 2013年第6期716-728,共13页
Land change science (LCS) strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic mo... Land change science (LCS) strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic model, and household survey method, this study investigated major land use changes and their causes from 1978 to 2008 in Uxin Banner (county-level), Inner Mongolia in China and then developed an understanding of the relationships between household livelihood and land-use pattern. Results showed that cultivated land increased from 1988 to 2000, and leveled offafter 2000. Built-up land increased stably for the period 1978 2008. The change of grassland and bare land differed among the three periods. From 1978 to 1988, grassland increased by 23.3%, and bare land decreased by 20.48%. From 1988 to 2000, bare land expanded by 1.7%, but grassland declined by 1.3%. From 2000 to 2008, an increase in grassland area by 1.8% was observed, but a decrease in bare land area by 9.0% was witnessed. The autologistic models performed better than logistic models as indicated by lower Akaike Information Criterion (AIC) values. Factors associated with human activities significantly correlated with the change of cultivated land, forest land, grassland, and built-up land. The produce prices and extensive cultivated land use are major issues in the farming area. This study suggests that completing land circulation systems and maintaining the stability of price are effective solutions. By contrast, reclamation and overgrazing are major concerns in the pastoral areas. Implementing environmental policies effectively, transferring population out of rural pastoral areas, and developing modem animal husbandry are effective ways to address these issues. 展开更多
关键词 farming-pastoral transitional region land use change driving force LIVELIHOOD autologistic model Uxin Banner(county-level) Inner Mongolia
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Influence of the deposition parameters on the transition region of hydrogenated silicon films growth 被引量:2
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作者 雷青松 吴志猛 +2 位作者 耿新华 赵颖 奚建平 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第11期2342-2347,共6页
Hydrogenated microcrystalline and amorphous silicon thin films were prepared by very high frequency plasmaenhanced chemical vapour deposition (VHF PECVD) by using a mixture of silane and hydrogen as source gas. The ... Hydrogenated microcrystalline and amorphous silicon thin films were prepared by very high frequency plasmaenhanced chemical vapour deposition (VHF PECVD) by using a mixture of silane and hydrogen as source gas. The influence of deposition parameters on the transition region of hydrogenated silicon films growth was investigated by varying the silane concentration (SC), plasma power (Pw), working pressure (P), and substrate temperature (Ts). Results suggest that SC and Ts are the most critical factors that affect the film structure transition from microcrystalline to amorphous phase. A narrow region in the range of SC and Ts, in which the rapid phase transition takes place, was identified. It was found that at lower P or higher Pw, the transition region is shifted to larger SC. In addition, the dark conductivity and photoconductivity decrease with SC and show sharp changes in the transition region. It proposed that the transition process and the transition region are determined by the competition between the etching effect of atomic hydrogen and the growth of amorphous phase. 展开更多
关键词 microcrystalline silicon amorphous silicon transition region VHF PECVD
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The heating of the solar transition region 被引量:1
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作者 Wen-Bin Song Xue-Shang Feng Fang Shen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第6期529-532,共4页
The temperature curve in the solar chromosphere has puzzled astronomers for a long time. Referring to the structure of supergranular cells, we propose an inductive heating model. It mainly includes the following three... The temperature curve in the solar chromosphere has puzzled astronomers for a long time. Referring to the structure of supergranular cells, we propose an inductive heating model. It mainly includes the following three steps. (1) A small-scale dynamo exists in the supergranulation and produces alternating small-scale magnetic fluxes; (2) The supergranular flow distributes these small-scale fluxes according to a regular pattern; (3) A skin effect occurs in the alternating and regularly-distributed magnetic fields. The induced current is concentrated near the transition region and heats it by resistive dissipation. 展开更多
关键词 SUN transition region -- Sun GRANULATION
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A Novel Fast Algorithm of Mono Transition Region Determination with Gray Image 被引量:1
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作者 ZhangAi-hua 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第3期309-312,共4页
There is a transition region between objects and background in any gray image. Many valuable applications of image segmentation and edge detection based on transition region determination have been developed in recent... There is a transition region between objects and background in any gray image. Many valuable applications of image segmentation and edge detection based on transition region determination have been developed in recent years. But, the complexity of calculation for determining transition region is too high. It results in the very limitation of applications based on transition region. A new novel fast method for transition region determination is presented in this paper, which will reduce the complexity of calculation dramatically. Many experiments have showed that this algorithm is effective and correct and will lay a good foundation for applications based on transition region. Key words image segmentation - transition region - maximum point - efficient average gradient (EAG) CLC number TP 391.4 Biography: Zhang Ai-hua (1965-), male, Ph. D candidate, research direction: image processing. 展开更多
关键词 image segmentation transition region maximum point efficient average gradient (EAG)
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A NEW ALGORITHM FOR DETECTING THE TRANSITION REGION ON NOISE IMAGE 被引量:1
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作者 Wang Hui Luo Jianping(Faculty of Information Eng., Shenzhen University, Shenzhen 518060) 《Journal of Electronics(China)》 2003年第4期279-284,共6页
An algorithm of ramp width reduction based on the gray information of neighborhood pixels is proposed, which can sharpen the ramp edge effectively. Then, a new gray-weighted gradient operator and the automatic method ... An algorithm of ramp width reduction based on the gray information of neighborhood pixels is proposed, which can sharpen the ramp edge effectively. Then, a new gray-weighted gradient operator and the automatic method to determine its parameter are introduced when detecting the transition region of images. Gray-weighted gradient operator can not only make the correlation of gradient and gray information as big as possible, but also resist the noise in the images. Some experiments show that the algorithm in this paper can extract the transition region more effectively. 展开更多
关键词 Ramp edge Width reduction transition region Gray-weighted gradient operator
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The Emission Heights of Transition Region Lines in an Equatorial Coronal Hole and the Surrounding Quiet Sun 被引量:1
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作者 Hui Tian Li-Dong Xia +2 位作者 Jian-Sen He Bo Tan Shuo Yao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第6期732-742,共11页
Using the correlation between the radiance or Doppler velocity and the extrapolated magnetic field, we determined the emission heights of a set of solar transition region lines in an equatorial coronal hole and in the... Using the correlation between the radiance or Doppler velocity and the extrapolated magnetic field, we determined the emission heights of a set of solar transition region lines in an equatorial coronal hole and in the surrounding quiet Sun region. We found that for all of the six lower-transition-region lines, the emission height is about 4-5 Mm in the equatorial coronal hole, and around 2 Mm in the quiet Sun region. This result confirms the previous findings that plasma with different temperature can coexist at the same layer of transition region. In the quiet Sun region, the emission height of the upper-transition-region line Ne VIII is almost the same that of the lower-transition-region line, but in the coronal hole, it is twice as high. This difference reveals that the outflow of Ne VIII is a signature of solar wind in the coronal hole and is just a mass supply to the large loops in the quiet Sun. 展开更多
关键词 Sun: transition region Sun: magnetic fields Sun: solar wind Sun: UV radiation
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Probing the solar transition region: current status and future perspectives 被引量:4
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作者 Hui Tian 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第11期1-18,共18页
The solar transition region (TR) is the temperature regime from roughly 0.02 MK to 0.8 MK in the solar atmosphere. It is the transition layer from the collisional and partially ionized chromosphere to the collisionl... The solar transition region (TR) is the temperature regime from roughly 0.02 MK to 0.8 MK in the solar atmosphere. It is the transition layer from the collisional and partially ionized chromosphere to the collisionless and fully ionized corona. The TR plays an important role in the mass and energy transport in both the quiet solar atmosphere and solar eruptions. Most of the TR emission lines fall into the spectral range of far ultraviolet and extreme ultraviolet (~400/^-1600/~). Imaging and spec- troscopic observations in this spectral range are the most important ways to obtain information about the physics of the TR. Static solar atmosphere models predict a very thin TR. However, recent high- resolution observations indicate that the TR is highly dynamic and inhomogeneous. I will summarize some major findings about the TR made through imaging and spectroscopic observations in the past 20 years. These existing observations have demonstrated that the TR may be the key to understanding coronal heating and origin of the solar wind. Future exploration of the solar TR may need to focus on the upper TR, since the plasma in this temperature regime (0.1 MK-0.8 MK) has not been routinely imaged before. High-resolution imaging and spectroscopic observations of the upper TR will not only allow us to track the mass and energy from the lower atmosphere to the corona, but also help us to understand the initiation and heating mechanisms of coronal mass ejections and solar flares. 展开更多
关键词 Sun: transition region -- Sun: corona -- Sun: flares -- Sun: coronal mass ejections --instrumentation: spectrographs
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Transitional Description of Diatomic Molecules in U(4) Vibron Model
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作者 ZHANGXin PANFeng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期29-36,共8页
U(3)-O(4) transitional description of diatomic molecules in the U(4) vibron model is studied by usingthe algebraic Bethe ansatz, in which the O(4) limit is a special case of the theory. Vibrational band-heads of somet... U(3)-O(4) transitional description of diatomic molecules in the U(4) vibron model is studied by usingthe algebraic Bethe ansatz, in which the O(4) limit is a special case of the theory. Vibrational band-heads of sometypical diatomic molecules are fitted by both transitional theory and the O(4) limit within the same framework. Theresults show that there are evident deviations from the O(4) limit in description of vibrational spectra of some diatomicmolecules. 展开更多
关键词 U(4) vibron model U(3)-O(4) transitional region Bethe ansatz O(4) limit vibrational spectra of diatomic molecules
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Interface behavior and microstructure transformation of welded joint of 35CrMo steel by electro-spark deposition 被引量:4
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作者 张富巨 马立卿 +1 位作者 张国栋 孙峰 《China Welding》 EI CAS 2005年第1期15-18,共4页
Electro-spark deposition has been carried out on the 35CrMo steel by filling and restoring the simulated slot specimens, and continuous surface coating with extra low porosity was obtained with proper parameters. The ... Electro-spark deposition has been carried out on the 35CrMo steel by filling and restoring the simulated slot specimens, and continuous surface coating with extra low porosity was obtained with proper parameters. The microstructure transformation and interface behavior of deposited joint were observed and analyzed. It shows that a transition region with 15μm in depth was obtained between base metal and deposited metal, and metallurgical bonding was achieved between restored base metal and deposition coating. 展开更多
关键词 electro-spark deposition transition region metallurgical bonding
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Location of energy source for coronal heating on the photosphere 被引量:2
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作者 Zhen-Xiang Hong Xu Yang +3 位作者 Ya Wang Kai-Fan Ji Hai-Sheng Ji Wen-Da Cao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第3期39-48,共10页
It is reported that ultra-fine dynamic ejections along magnetic loops of an active region origi- nate from intergranular lanes and they are associated with subsequent heating in the corona. As continu- ing work, we an... It is reported that ultra-fine dynamic ejections along magnetic loops of an active region origi- nate from intergranular lanes and they are associated with subsequent heating in the corona. As continu- ing work, we analyze the same set of data but focus on a quiet region and the overlying EUV/UV emis- sion as observed by the Atmospheric Imaging Assembly (AIA) on board Solar Dynamics Observatory (SDO). We find that there appear to be dark patches scattered across the quiet region and the dark patches always stay along intergranular lanes. Over the dark patches, the average UV/EUV emission at 131, 17 1, 304 and 1600 A (middle temperature) is more intense than that of other regions and EUV brightness is negatively correlated with 10830A intensity, though, such a trend does not exist for high temperature lines at 94, 193, 211 and 335 A. For the same quiet region, where both TiO 7057 A broad band images and 10830A filtergrams are available, contours for the darkest lane areas on TiO images and clark patches on 10830A filtergrams frequently differ in space. The results suggest that the dark patches do not simply reflect the areas with the darkest lanes but are associated with a kind of enhanced absorption (EA) at 10830A,. A strict definition for EA with narrow band 10830A filtergrams is found to be difficult. In this paper, we define enhanced absorption patches (EAPs) of a quiet region as the areas where emission is less than ,-90% of the mean intensity of the region. The value is equivalent to the average intensity along thin dark loops connecting two moss regions of the active region. A more strict definition for EAPs, say 88%, gives even more intense UV/EUV emission over those in the middle temperature range. The results provide further observational evidence that energy for heating the upper solar atmosphere comes from the intergranular lane area where the magnetic field is constantly brought in by convection motion in granules. 展开更多
关键词 atmosphere - Sun photosphere - Sun transition region - Sun CORONA
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A Possible Interpretation of Burst-Like Characteristics of Explosive Events 被引量:1
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作者 FANQuan-Lin FENGXue-Shang XIANGChang-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期790-794,共5页
Explosive events have been observed to occur consecutively in bursts at intermittent locations along theboundary near the opposite polarity. The aim of the present paper is to explore a possible mechanism to interpret... Explosive events have been observed to occur consecutively in bursts at intermittent locations along theboundary near the opposite polarity. The aim of the present paper is to explore a possible mechanism to interpret thisburst-like characteristic of explosive events. The 2D magnetohydrodynamic (MHD) numerical simulations with resistivityhave been carried out to reproduce the intermittent spatial-temporal magnetic reconnection events taking place along thelong, compressible current sheet. The observed density enhancements in previously published results have been verifiedto be associated to magnetic reconnection sites. Late observational evidences, which support present attempts, have alsobeen found, at least in morphological evolution of the consecutive explosive events. 展开更多
关键词 explosive events magnetic reconnection MAGNETOHYDRODYNAMICS solar transition region numerical simulation
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Research on the optimum hydrogenated silicon thin films for application in solar cells 被引量:1
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作者 雷青松 吴志猛 +3 位作者 耿新华 赵颖 孙健 奚建平 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期3033-3038,共6页
Hydrogenated silicon (Si:H) thin films for application in solar ceils were deposited by using very high frequency plasma enhanced chemical vapour deposition (VHF PECVD) at a substrate temperature of about 170 ℃,... Hydrogenated silicon (Si:H) thin films for application in solar ceils were deposited by using very high frequency plasma enhanced chemical vapour deposition (VHF PECVD) at a substrate temperature of about 170 ℃, The electrical, structural, and optical properties of the films were investigated. The deposited films were then applied as i-layers for p-i-n single junction solar cells. The current-voltage (I - V) characteristics of the cells were measured before and after the light soaking. The results suggest that the films deposited near the transition region have an optimum properties for application in solar cells. The cell with an i-layer prepared near the transition region shows the best stable performance. 展开更多
关键词 hydrogenated silicon thin film transition region Si:H thin film solar cell STABILITY
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Numerical simulation of superhalo electrons generated by magnetic reconnection in the solar wind source region 被引量:2
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作者 Li-Ping Yang Ling-Hua Wang +4 位作者 Jian-Sen He Chuan-Yi Tu Shao-Hua Zhang Lei Zhang Xue-Shang Feng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第3期348-362,共15页
Superhalo electrons appear to be continuously present in the interplane- tary medium, even during very quiet times, with a power-law spectrum at energies above ~2 keV. Here we numerically investigate the generation o... Superhalo electrons appear to be continuously present in the interplane- tary medium, even during very quiet times, with a power-law spectrum at energies above ~2 keV. Here we numerically investigate the generation of superhalo electrons by magnetic reconnection in the solar wind source region, using magnetohydrody- namics and test particle simulations for both single X-line reconnection and multiple X-line reconnection. We find that the direct current electric field, produced in the mag- netic reconnection region, can accelerate electrons from an initial thermal energy of T ~105 K up to hundreds of keV. After acceleration, some of the accelerated elec- trons, together with the nascent solar wind flow driven by the reconnection, propagate upwards along the newly-opened magnetic field lines into interplanetary space, while the rest move downwards into the lower atmosphere. Similar to the observed superhalo electrons at 1 AU, the flux of upward-traveling accelerated electrons versus energy dis- plays a power-law distribution at ~ 2-100 keV, f(E)~ E^-δ, with a 6 of ~1.5 - 2.4. For single (multiple) X-line reconnection, the spectrum becomes harder (softer) as the anomalous resistivity parameter a (uniform resistivity η) increases. These modeling results suggest that the acceleration in the solar wind source region may contribute to superhalo electrons. 展开更多
关键词 acceleration of particles -- methods:numerical -- Sun:particle emission-- (Sun:) solar wind -- Sun: transition region
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GRAIN SHAPE EFFECT IN SUPERPLASTIC DEFORMATION
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作者 CUI Jianzhong MA Longxiang Northeast University of Technology,Shenyang,China Department of Metals Forming,Northeast University of Technology,Shenyang,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第7期61-67,共7页
The method controlling grain shape in TMT processing and the effect of grain shape on char- acteristic parameters in superplastic deformation were discussed.The accommodation velocity of grahl boundary sliding,which i... The method controlling grain shape in TMT processing and the effect of grain shape on char- acteristic parameters in superplastic deformation were discussed.The accommodation velocity of grahl boundary sliding,which is the dominant mechanism in superplastic deformation,and the contribution of each mechanism to the total strain,as influenced by grain shape,were ana- lyzed.Grain shape has been shown to be an essential structural factor for superplasticity.Then an analysis was made about the effect of grain shape on the region transition strain rate so that a new concept,critical aspect for superplasticity,was worked out.These predictions were compared with the measured results in an Al-Zn-Mg alloy. 展开更多
关键词 superplastic deformation thermomechanical treatment(TMT) grain shape grain boundary sliding region transition
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Quantum properties near the instability boundary in optomechanical system
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作者 Han-Hao Fang Zhi-Jjiao Deng +1 位作者 Zhigang Zhu Yan-Li Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第3期201-207,共7页
The properties of the system near the instability boundary are very sensitive to external disturbances, which is important for amplifying some physical effects or improving the sensing accuracy. In this paper, the qua... The properties of the system near the instability boundary are very sensitive to external disturbances, which is important for amplifying some physical effects or improving the sensing accuracy. In this paper, the quantum properties near the instability boundary in a simple optomechanical system have been studied by numerical simulation. Calculations show that the transitional region connecting the Gaussian states and the ring states when crossing the boundary is sometimes different from the region centered on the boundary line, but it is more essential. The change of the mechanical Wigner function in the transitional region directly reflects its bifurcation behavior in classical dynamics. Besides, quantum properties, such as mechanical second-order coherence function and optomechanical entanglement, can be used to judge the corresponding bifurcation types and estimate the parameter width and position of the transitional region. The non-Gaussian transitional states exhibit strong entanglement robustness, and the transitional region as a boundary ribbon can be expected to replace the original classical instability boundary line in future applications. 展开更多
关键词 optomechanical system instability boundary transitional region quantum properties
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Study on fine structure of crust-mantle transi-tion zone in Yanqing-Hailai basin based on CDP and DSS data
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作者 成瑾 李清河 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第1期78-85,共8页
The fine structure of crust mantle transition zone in Yanqing Hailai(Yan Huai basin) basin has been analyzed and discussed by using the data of Yanqing Hailai deep seismic reflection profile and Beijing Huailai ... The fine structure of crust mantle transition zone in Yanqing Hailai(Yan Huai basin) basin has been analyzed and discussed by using the data of Yanqing Hailai deep seismic reflection profile and Beijing Huailai Fengzhen deep seismic sounding profile obtained respectively in 1992 and in 1993. The primary model is established based on CDP stacking profile. The phases of seismic refraction waves and wide angle reflection waves are analyzed, travel time inversion is carried out and 2 D ray tracing is computed. Synthetic seismograms are completed by using re flectivity method for waveform fitting of phases P M and P M′, they are reflection waves from both the upper and the lower boundaries of the crust mantle transition zone in this basin. The results show that the P M′ reflection waves are stronger at some points and come from the lower boundary of Moho discontinuity. It is confirmed and inter preted that the Moho discontinuity in Yanqing Hailai basin consists of a group of thin layers with alternatively higher and lower velocities. 展开更多
关键词 seismic reflection and refraction Yanqing Hailai basin fine structure CRUST mantle transition region travel time inversion
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AIM Study on the Reaction of CH2SH Radical with Fluorine Atom
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作者 Cui-hong Suna Yan-li Zeng +1 位作者 Ling-peng Meng Shi-jun Zheng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第2期123-130,共8页
The reaction of CH2SH radical with fluorine atom was studied at the levels of B3LYP/6-311G(d,p) and MP2(Full)/6-311G(d,p). The computational results show that the reaction has three channels and proceeds by the ... The reaction of CH2SH radical with fluorine atom was studied at the levels of B3LYP/6-311G(d,p) and MP2(Full)/6-311G(d,p). The computational results show that the reaction has three channels and proceeds by the addition of fluorine atoms on carbon or sulfur sites of CH2SH, forming initial intermediates. The calculated results show that the channel, in which fluorine attaches to the carbon atom to form CH2S and HF, is the most likely reaction pathway. Topological analysis of electron density was carried out for the three channels. The change trends of the chemical bonds on the reaction paths were discussed. The energy transition states and the structure transition regions (states) of the three channels were found. The calculated results show that the structure transition regions are broad in unobvious exothermic reactions or unobvious endothermic reactions, and are narrow in obvious exothermic reactions or obvious endothermic reactions. 展开更多
关键词 Radical reaction Energy transition state Structure transition state Structure transition region Topological analysis of electronic density
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An Impulsive Heating Model for the Evolution of Coronal Loops
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作者 Li Feng Wei-Qun Gan 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第5期608-616,共9页
It was suggested by Parker that the solar corona is heated by many small energy release events generally called microflares or nanoflares. More and more observations showed flows and intensity variations in nonflaring... It was suggested by Parker that the solar corona is heated by many small energy release events generally called microflares or nanoflares. More and more observations showed flows and intensity variations in nonflaring loops. Both theories and observations have indicated that the heating of coronal loops should actually be unsteady. Using SOLFTM (Solar Flux Tube Model), we investigate the hydrodynamics of coronal loops undergoing different manners of impulsive heating with the same total energy deposition. The half length of the loops is 110 Mm, a typical length of active region loops. We divide the loops into two categories: loops that experience catastrophic cooling and loops that do not. It is found that when the nanoflare heating sources are in the coronal part, the loops are in non-catastrophic-cooling state and their evolutions are similar. When the heating is localized below the transition region, the loops evolve in quite different ways. It is shown that with increasing number of heating pulses and inter-pulse time, the catastrophic cooling is weakened, delayed, or even disappears altogether. 展开更多
关键词 hydrodynamics -- Sun corona -- Sun transition region
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