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511.
512.
<正>Objective The development of continental rifting and seafloor spreading can be predominated by magmatic upwelling(magma-rich)or tectonic stretching(magma-poor).Located in the terminal portion of propagating seafloor spreading of the South China Sea(SCS),the southwestern mid-ridge of the southwest sub-basin(SWSB)of the SCS 相似文献
513.
One of the basic characteristics of Earth’s modern climate is that the Northern Hemisphere(NH) is climatologically warmer than the Southern Hemisphere(SH). Here, model performances of this basic state are examined using simulation results from 26 CMIP6 models. Results show that the CMIP6 models underestimate the contrast in interhemispheric surface temperatures on average(0.8 K for CMIP6 mean versus 1.4 K for reanalysis data mean), and that there is a large intermodel spread, ranging from -0.7 K... 相似文献
514.
To explore the livelihood status and key influencing factors of rural households in the minority areas, we collected flat data from 284 rural households in 32 villages across 12 counties of Western Sichuan from 2021 to 2022. We conducted participatory household survey on the livelihood status of the rural households and try to identify the key factors to influence their livelihood vulnerability using multiple linear regression. The results showed that: the livelihood situation of the rural house... 相似文献
515.
TANG Ligen ZHU Weiyao ZHU Huayin SUN Chunhui YANG Fenglai WANG Yan Li Xiaorui Li Haiming CHU Guangzhen WANG Jieming KONG Debin YUE Ming LIU Yuwei HUANG Kun 《《地质学报》英文版》2021,95(2):630-637
To tackle the problem that wells that are deployed in a specific pattern based on the requirements of gas reservoir development are not suitable for gas storage,we have conducted concentrically circular injection and production simulation experiments for gas storage,discovered the existence of a threshold radius,denoted by Rt, and derived the expression for Rt.Based on the analysis and discussion results,we propose a strategy for deploying gas storage wells in specific patterns.The expression for Rt shows that it is affected by factors such as the gas storage gas production/injection time,the upper pressure limit,the lower pressure limit,the bottomhole flow pressure at the ends of injection and production,the and permeability. The analysis and discussion results show that the Rt of a gas storage facility is much smaller than the Rt for gas reservoir development.In the gas storage facilities in China,the Rt for gas production is less than the Rt for the gas injection, and Rt increases with the difference in the operating pressure and with permeability K.Based on the characteristics of Rt,we propose three suggestions for gas storage well pattern deployment:(1)calculate Rt according to the designed functions of the gas storage facility and deploy the well pattern according to Rt;(2) deploy sparser,large-wellbore patterns in high-permeability areas and denser,small-wellbore patterns in high-permeability areas;and (3)achieve the gas injection well pattern by new drilling,and the gas production well pattern through a combination of the gas injection well pattern and old wells.By assessing a gas storage facility with a perfect well pattern after a number of adjustments,we found that the Rt of the 12 wells calculated in this paper is basically close to the corresponding actual radius,which validates our method.The results of this study provide a methodological basis for well pattern deployment in new gas storage construction. 相似文献
516.
LATE CENOZOIC RAPID UPLIFT OF THE TIBETAN PLATEAU AND FORMATION OF ASIAN MONSOON SYSTEM:EVIDENCE FROM PALEOMAGNETISM AND PALEOBIOLOGY OF RED BED-BOULDER CONGLOMERATE SEQUENCES ALONG THE NORTHERN TIBET PLATEAU 相似文献
517.
From 28 March to 17 April, 2018, different forms of mercury(Hg) in the Yellow Sea and Bohai Sea were measured to study the influencing factors on the distribution and transformation of Hg in spring using a shared cruise. The mean concentration of dissolved gaseous mercury(DGM) in the surface water of the Yellow and Bohai Seas was(44.3 ± 43.9) pg/L, which was close to that in mid-latitude oceans and deep seas. The ratio of DGM to THg(total mercury) was lower than in the oceans and in the Yellow and Bohai Seas in summer or fall. DGM concentrations in surface water were highest in the central part of the South Yellow Sea and were higher than those in the Bohai Sea, and their spatial distributions were consistent with RHg(reactive mercury). DGM and RHg correlated positively with water temperature in surface seawater(r = 0.506, P < 0.01;r = 0.278, P < 0.05). The concentrations of both DGM and RHg in surface water were controlled by solar radiation and water temperature. Foggy weather did not benefit the production of DGM and RHg. DGM in the bottom seawater was mainly affected by Dissolved Oxygen and water temperature(r =-0.366, P < 0.01;r = 0.331, P < 0.01), produced mainly by anaerobic reactions of the bottom seawater and sediment microorganisms. The bottom DGM concentrations in the Yellow and Bohai Seas were the highest, and DGM produced in bottom seawater and sediment plays a more important role than the surface water in spring. The concentrations of DGM and RHg in the surface and bottom water in the South Yellow Sea were all higher than those in the middle layer. Vertical variations in the North Yellow Sea and the Bohai Sea were small. The production and distribution of DGM and RHg were influenced by differences of latitude and by the Yellow Sea warm current in spring. 相似文献
518.
Dong Zhang Rong-Bing Zhao Zhen Yan Wei-Hua Shang-Guan Qian Ye Zhi-Qiang Shen Qing-Hui Liu Jin-Qing Wang Li Fu Chu-Yuan Zhang Dong-Fang Song Si-Yu Liu 《天文和天体物理学研究(英文版)》2023,(11):227-233
The Tian-ma Radio Telescope(TMRT) applies an Active Surface System(ASFS), which corrects for large-scale deformations due to gravity and thermal on the primary reflector. The centralized and automated management of the ASFS using software has become a challenge, for which we have developed the TMRT Active Surface System Control Software(TASCS). This paper describes the design and implementation of TASCS for device control,status monitoring, human-computer interaction, and data management functio... 相似文献
519.
Shang-Biao Sun Jian-Guo Yan Wu-Tong Gao Bo Wang Zhen Wang Mao Ye Jean-Pierre Barriot 《天文和天体物理学研究(英文版)》2023,(9):131-143
Most asteroids and comets are formed in the early stages of the solar system and therefore contain a wealth of information about their birth. The asteroid exploration mission planned in the coming years by China will likely target the celestial body named 133P/Elst-Pizarro(estimated diameter of about 4 km). The orbit of this asteroid stays within the asteroid belt, but nevertheless, it displays a comet-like dust tail. In this study, we used differential tracking data between two simulated probes... 相似文献
520.
The principal characteristics of the tides are investigated by a shipborne acoustic Doppler current Profiler at a fixed station located in the Beibu Gulf from 4 to 14 April 2003. Data analysis indicates that the diurnal tidal currents dominate local current variations at the observing site. Except the barotropic M_2 constituent, four principal tides comprise both back-and-forth barotropic and baroclinic tidal currents. The baroclinic tidal ellipse parameters vary with depth, showing complicate features, rather than monotonous features being figured. For baroclinic tidal constituents, vertical modes are different to each other. Similarly, the semi-major axes of the tidal constituents vary with depth. In the lower layer, a nonlinear regression approach is used to calculate and obtain the SEMA profiles of diurnal tidal constituents. Results show that in the thin bottom boundary layer, all of the parameters vary drastically with depth, totally distinguished from the vertical profiles above. 相似文献