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Effects of Sowing Rate on Marginal Superiority and Yield of Wheat in Wheat-cotton Intercropping System
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作者 王树林 祁虹 +4 位作者 王燕 张谦 冯国艺 林永增 梁青龙 《Agricultural Science & Technology》 CAS 2015年第12期2649-2652,共4页
In the wheat-cotton intercropping system, total 6 sowing rates (187.5, 225.0, 262.5, 300.0, 337.5 and 375.0 kg/hm2) were arranged, and the effects of sowing rate on marginal superiority and yield of wheat were inves... In the wheat-cotton intercropping system, total 6 sowing rates (187.5, 225.0, 262.5, 300.0, 337.5 and 375.0 kg/hm2) were arranged, and the effects of sowing rate on marginal superiority and yield of wheat were investigated. The re- sults showed that the effect of sowing rate on inner-line wheat was greater than that on side-line wheat; with the increased sowing rate, the marginal superiority of panicle number was reduced in overall, and the difference in panicle number be- tween inner and side lines was decreased from 9.0×10^5/hm2 (sowing rate of 187.5 kg/hm2) to 7.8×10^5/hm2 (sowing rate of 375.0 kg/hm2); the marginal superiority of grains per spike was increased first and then reduced, and the largest difference in grains per spike between the inner and side lines reached 4.6 under the sowing rate of 300.0 kg/hm2; the marginal superiority of 1 000-grain weight and yield was gradually increased, and the largest difference in 1 000-grain weight between the inner and side lines reached 3.9 g under the sowing rate of 337.5 kg/hm2, and in yield reached 3 136.5 kg/hm2under the sowing rate of 375.0 kg/hm2. The effects of sowing rate on the three yield factors of intercropped wheat ranked as panicle number 〉 grains per spike 〉 1 000-grain weight. The appropriate sowing rate of wheat was 225.0-262.0 kg/hm2 in the wheat-cotton intercropping system. 展开更多
关键词 Wheat-cotton intercropping WHEAT Sowing rate marginal superiority YIELD
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Analysis on Marginal Superiority and Yield of Different Wheat Varieties in Wheat-cotton Intercropping System
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作者 王树林 祁虹 +4 位作者 王燕 张谦 冯国艺 林永增 梁青龙 《Agricultural Science & Technology》 CAS 2016年第5期1077-1079,共3页
In wheat-cotton intercropping system,the spike number per unit area,grains per spike,thousand-grain weight and yield of side line and inner line were investigated in six wheat varieties to study the marginal superiori... In wheat-cotton intercropping system,the spike number per unit area,grains per spike,thousand-grain weight and yield of side line and inner line were investigated in six wheat varieties to study the marginal superiority and select suitable wheat varieties intercropped with cotton.The results showed that Xingmai No.4had obvious marginal superiority with the yield of 6 919.0 kg/hm2,so it was the suitable variety for wheat-cotton intercropping system. 展开更多
关键词 Wheat-cotton intercropping Wheat variety marginal superiority
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Tectonic Setting and Metallogenic System of North China Block Margins 被引量:6
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作者 Zhai Yusheng Deng Jun Xiao Rongge Peng Runmin Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 1999年第1期34-37,共4页
The paleocontinental margins have frequent and intensive tectonic movement and various ore forming processes. According to their tectono dynamic characteristics, the paleocontinental margins can be classified into t... The paleocontinental margins have frequent and intensive tectonic movement and various ore forming processes. According to their tectono dynamic characteristics, the paleocontinental margins can be classified into three types: the divergent, the convergent and the transformational. Each type has its specific geological geochemical processes and metallogenic system. The paper discusses the tectonic evolution and ore forming features of the North China block margins, puts forward conceptions such as complexity, variety and multi stage development of metallogenic evolution in the paleocontinental margins, and expounds five factors controlling the formation of large superlarge ore deposits in the paleocontinental margins: (1) channelway, (2) rendezvous of fluids, (3) abundance of ore source, (4) thermo dynamic anomaly, (5) long duration of structural activities. 展开更多
关键词 paleocontinental margin metallogenic system North China block tectonic evolution superlarge ore deposit.
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Metallogenic Systems on the Paleocontinental Margin of the North China Craton 被引量:3
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作者 ZHAIYusheng DENGJun +5 位作者 TANGZhongli XIAORongge SONGHonglin PENGRunmin SUNZhongshi WANGJianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期592-603,共12页
The North China Craton (NCC) is one of the largest blocks composing the continent. Different types of continental margins well developed around the NCC, along with lots of metallogenic systems of different metals and ... The North China Craton (NCC) is one of the largest blocks composing the continent. Different types of continental margins well developed around the NCC, along with lots of metallogenic systems of different metals and different times. Based on the study on the structural evolution of the NCC, the authors made a new division of tectonic units of the NCC. Through an analysis of the data of 1:25000 geochemical survey on stream sediments, regional geochemical features of main ore-forming elements including Au, Ag, Cu, Pb, Zn, W, Ni, Co and Mo of the NCC are discussed in the paper. Then different metallogenic systems and their forming processes and geodynamics are discussed in detail. At last, temporal and spatial distribution regularities are summarized and ten favorable ore-control factors on the paleocontinental margins are put forward, including (1) abundance of ore sources; (2) rendezvous of ore-forming fluids; (3) high thermo-dynamic anomaly; (4) remarkable Earth crust-mantle interaction; (5) cluster of macroscopic structures and their long activities; (6) diversity of ore-forming environments; (7) long geohistory; (8) multiforms of critical transitional ore-forming mechanisms; (9) multi-staged and superimposed ore-formation; and (10) suitable preservation condition. 展开更多
关键词 North China Craton Paleocontinental margin metallogenic systems metallogenic evolution
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Inversion of two-phase extensional basin systems during subduction of the Paleo-Pacific Plate in the SW Korean Peninsula:Implication for the Mesozoic “Laramide-style” orogeny along East Asian continental margin 被引量:1
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作者 Seung-Ik Park Jungrae Noh +4 位作者 Hee Jun Cheong Sanghoon Kwon Yungoo Song Sung Won Kim M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第3期909-925,共17页
During subduction, continental margins experience shortening along with inversion of extensional sedimentary basins. Here we explore a tectonic scenario for the inversion of two-phase extensional basin systems, where ... During subduction, continental margins experience shortening along with inversion of extensional sedimentary basins. Here we explore a tectonic scenario for the inversion of two-phase extensional basin systems, where the Early-Middle Jurassic intra-arc volcano-sedimentary Oseosan Volcanic Complex was developed on top of the Late Triassic-Early Jurassic post-collisional sequences, namely the Chungnam Basin. The basin shortening was accommodated mostly by contractional faults and related folds. In the basement, regional high-angle reverse faults as well as low-angle thrusts accommodate the overall shortening, and are compatible with those preserved in the cover. This suggests that their spatial and temporal development is strongly dependent on the initial basin geometry and inherited structures.Changes in transport direction observed along the basement-sedimentary cover interface is a characteristic structural feature, reflecting sequential kinematic evolution during basin inversion. Propagation of basement faults also enhanced shortening of the overlying sedimentary cover sequences. We constrain timing of the Late Jurassic-Early Cretaceous(ca. 158-110 Ma) inversion from altered K-feldspar 40 Ar/39 Ar ages in stacked thrust sheets and K-Ar illite ages of fault gouges, along with previously reported geochronological data from the area. This "non-magmatic phase" of the Daebo Orogeny is contemporaneous with the timing of magmatic quiescence across the Korean Peninsula. We propose the role of flat/low-angle subduction of the Paleo-Pacific Plate for the development of the "Laramide-style" basement-involved orogenic event along East Asian continental margin. 展开更多
关键词 TWO-PHASE extensional basin systemS Paleo-Pacific Plate INVERSION tectonics “Laramide-style” OROGENY East Asian continental margin
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Characteristics of the Composite Metallogenic System along the Jilin Paleocontinental Margin and the Evolution of Continental Dynamic Regimes 被引量:1
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作者 SUNZhongshi JIANGYanguo +2 位作者 DENGJun CHEYingfang WANGJianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期571-582,共12页
In view of the existing problems about the metallogenic epoch and origin of the complex along the Jilin paleocontinental margin, we propose the composite metallogenic system of the Jilin old land, based on the theory ... In view of the existing problems about the metallogenic epoch and origin of the complex along the Jilin paleocontinental margin, we propose the composite metallogenic system of the Jilin old land, based on the theory of metallogeny and from the continental dynamics and comprehensive analysis on the metallogenic characteristics. Its scientific theory is demonstrated by the following aspects: (1) Screening and analysis of the multi-stage super-imposition and sequences. The composite ore-forming system consists mainly of three types: the divergent-type epicontinental metallogenic system on the southern margin, the convergent-type epicontinental metallogenic system on the northern margin and the strike-slip-type epicontinental metallogenic system on the northeastern margin. Their major metallogenic epochs are Archean-Proterozoic, Variscan and Yanshanian respectively. (2) Comprehensive analysis of the genetic relations of the complicated deposits. The above-mentioned three types all indicate a consanguinity among granites, vein rocks and gold deposits, correspondence with geochemical elements, and unicity showing the same activities of mantle derived fluids and multi-source origin of ore-forming substances. (3) As to the mechanisms for mineral concentration, in addition to the sources, we also focus on the co-actions of permeability, vibration, gas-liquid state alternation and abrupt changes of flow velocity during the movement of ore-forming liquids, as well as the extraction and communication of multi-sequence circulating liquids. (4) It is helpful for establishing the relationship between metallogeny and the evolution of continental dynamic regimes, i.e., the ore-controlling correlations between the ore-forming elements-metallogenic series-metallogenic systems-composite metallogenic system and ore-controlling structural features (stratabound, primary and branching types)-regional faulting or secondary continental extension and collision-transformation of different continental dynamic types (divergent, convergent and strike-slip)-the evolution process of the whole old land for the Jilin old land margin. All these are helpful for further researches on the continental metallogenic dynamics. 展开更多
关键词 composite metallogenic system continental dynamic mechanism Jilin paleocontinental margin
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Hydrocarbon accumulation and orderly distribution of whole petroleum system in marine carbonate rocks of Sichuan Basin,SW China 被引量:1
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作者 GUO Xusheng HUANG Renchun +3 位作者 ZHANG Dianwei LI Shuangjian SHEN Baojian LIU Tianjia 《Petroleum Exploration and Development》 SCIE 2024年第4期852-869,共18页
Based on the situation and progress of marine oil/gas exploration in the Sichuan Basin,SW China,the whole petroleum system is divided for marine carbonate rocks of the basin according to the combinations of hydrocarbo... Based on the situation and progress of marine oil/gas exploration in the Sichuan Basin,SW China,the whole petroleum system is divided for marine carbonate rocks of the basin according to the combinations of hydrocarbon accumulation elements,especially the source rock.The hydrocarbon accumulation characteristics of each whole petroleum system are analyzed,the patterns of integrated conventional and unconventional hydrocarbon accumulation are summarized,and the favorable exploration targets are proposed.Under the control of multiple extensional-convergent tectonic cycles,the marine carbonate rocks of the Sichuan Basin contain three sets of regional source rocks and three sets of regional cap rocks,and can be divided into the Cambrian,Silurian and Permian whole petroleum systems.These whole petroleum systems present mainly independent hydrocarbon accumulation,containing natural gas of affinity individually.Locally,large fault zones run through multiple whole petroleum systems,forming a fault-controlled complex whole petroleum system.The hydrocarbon accumulation sequence of continental shelf facies shale gas accumulation,marginal platform facies-controlled gas reservoirs,and intra-platform fault-and facies-controlled gas reservoirs is common in the whole petroleum system,with a stereoscopic accumulation and orderly distribution pattern.High-quality source rock is fundamental to the formation of large gas fields,and natural gas in a whole petroleum system is generally enriched near and within the source rocks.The development and maintenance of large-scale reservoirs are essential for natural gas enrichment,multiple sources,oil and gas transformation,and dynamic adjustment are the characteristics of marine petroleum accumulation,and good preservation conditions are critical to natural gas accumulation.Large-scale marginal-platform reef-bank facies zones,deep shale gas,and large-scale lithological complexes related to source-connected faults are future marine hydrocarbon exploration targets in the Sichuan Basin. 展开更多
关键词 Sichuan Basin margin oil/gas whole petroleum system carbonate hydrocarbon accumulation hydrocarbon distribution law hydrocarbon exploration target
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STABILITY MARGIN OF SYSTEMS WITH MIXED UNCERTAINTIES UNDER THE IQC DESCRIPTIONS
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作者 董海荣 耿志勇 +1 位作者 王金枝 黄琳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第11期1274-1281,共8页
Stability perturbation bounds problem for systems with mixed uncertainties is discussed. It is supposed that the linear part in the forward loop is of parametric uncertainties described by interval perturbation mode, ... Stability perturbation bounds problem for systems with mixed uncertainties is discussed. It is supposed that the linear part in the forward loop is of parametric uncertainties described by interval perturbation mode, and that the nonlinear part in the feedback loop is characterized by an integral quadratic constraint (IQC). The definition of stability margin under the interval perturbation mode is given by using the Minkowski functional. The infinite stability checking problem of the mixed uncertain system can be converted to finite or one dimensional stability checking for different structures of the IQC multipliers based on the concepts of biconvex and convex-concave junctions and their properties. The result is illustrated to be efficient through an example. 展开更多
关键词 system with mixed uncertainty perturbation margin integral quadratic constraint parametric uncertainty stability checking
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Systematics, species diversity and new taxa of mesozooplankton in the West Pacific Ocean and its marginal seas: a brief compilation of monographs in China
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作者 WANG Yu HUANG Zongguo +9 位作者 WANG Chunguang HUANG Jiangshiou LIU Zhensheng XU Zhenzu HUANG Jiaqi CHEN Ruixiang LIAN Guangshan DAI Yanyu LIN Jinghong LIN Mao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第10期229-242,共14页
Research and protection of biodiversity is generally started with species recognizing guided by achievement of cataloguing and illustration obtained through in situ investigation data accumulation and literature learn... Research and protection of biodiversity is generally started with species recognizing guided by achievement of cataloguing and illustration obtained through in situ investigation data accumulation and literature learning. Facing the shortage of taxonomist, it is getting harder to maintain important specimen collections and handle loans. The West Pacific Ocean has been operating as a center of the origin of global marine biodiversity result of the richest species diversity of marine taxa found in these waters. The present work is a compilation and summary of systematics, species diversity and new taxa of mesozooplankton major group known in West Pacific Ocean and its marginal seas (0°-45°N, 105°-152°E) according to 6 203 mesozooplankton samples acquired from 701 stations during 1965 and 2008. A total of 2 657 species belonging to 686 genera and 206 families of 10 mesozooplankton groups have been found through taxonomic identification and document consulting. In details, 697 species from 251 genera of 99 families belong to the Medusozoa, 59 species from 22 genera of 12 families to the Ctenophora, 85 species from 36 genera of 14 families to the pelagic Mollusca (Pteropoda and Heteropoda), 416 species from 91 genera of 8 families to the Ostracoda, 908 species from 156 genera of 51 families to the Copepoda, 202 species from 60 genera of 4 families to the Mysidacea, 56 species from 8 genera of 2 families to the Euphausiacea, 105 species from 23 genera of 8 families to the Decapoda, 48 species from 13 genera of 5 families to the Chaetognatha and 81 species from 26 genera of 5 families to the Tunicata. The dominant species of each group are enumerated. Moreover, 2 new species of Medusozoa, Tubulariidae, Ectopleura, 1 new species of Medusozoa, Protiaridae, Halitiarella, 1 new genus and 1 new species of Medusozoa, Corymorphidae are established. An amount of 806 species are expanded with an increase of 43.5% on the basis of 1 852 species recorded before 2008, including 1.4% increase from tropical sea around equator, 4.0% from the frigid water in high latitude region, and 3.0% of bathypelagic-associated waters. The authors also summarized future prospects into five major areas in marine mesozooplankton research in China. Such information of qualitative phyletic classification could be of high relevance to studies on biodiversity and biogeography of marine mesozooplankton, especially for monographs contributed to make an overall and systematic conclusion on the species of marine life in China after 2008. 展开更多
关键词 marine mesozooplankton systemATICS species diversity new taxa COMPILATION the West Pacific Ocean marginal sea
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Deep tectonics and seismogenic mechanisms of the seismic source zone of the Jishishan M_(s)6.2 earthquake on December 18,2023,at the northeast margin of the Tibetan Plateau 被引量:1
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作者 Qiong Wang ShuYu Li +3 位作者 XinYi Li Yue Wu PanPan Zhao Yuan Gao 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期514-521,共8页
On December 18,2023,an M_(s)6.2 earthquake occurred in Jishishan,Gansu Province,China.This earthquake happened in the eastern region of the Qilian Orogenic Belt,which is situated at the forefront of the NE margin of t... On December 18,2023,an M_(s)6.2 earthquake occurred in Jishishan,Gansu Province,China.This earthquake happened in the eastern region of the Qilian Orogenic Belt,which is situated at the forefront of the NE margin of the Tibetan Plateau(i.e.,Qinghai-Tibet Plateau),encompassing a rhombic-shaped area that intersects the Qilian-Qaidam Basin,Alxa Block,Ordos Block,and South China Block.In this study,we analyzed the deep tectonic pattern of the Jishishan earthquake by incorporating data on the crustal thickness,velocity structure,global navigation satellite system(GNSS)strain field,and anisotropy.We discovered that the location of the earthquake was related to changes in the crustal structure.The results showed that the Jishishan M_(s)6.2 earthquake occurred in a unique position,with rapid changes in the crustal thickness,Vp/Vs,phase velocity,and S-wave velocity.The epicenter of the earthquake was situated at the transition zone between high and low velocities and was in proximity to a low-velocity region.Additionally,the source area is flanked by two high-velocity anomalies from the east and west.The principal compressive strain orientation near the Lajishan Fault is primarily in the NNE and NE directions,which align with the principal compressive stress direction in this region.In some areas of the Lajishan Fault,the principal compressive strain orientations show the NNW direction,consistent with the direction of the upper crustal fast-wave polarization from local earthquakes and the phase velocity azimuthal anisotropy.These features underscore the relationship between the occurrence of the Jishishan M_(s)6.2 earthquake and the deep inhomogeneous structure and deep tectonic characteristics.The NE margin of the Tibetan Plateau was thickened by crustal extension in the process of northeastward expansion,and the middle and lower crustal materials underwent structural deformation and may have been filled with salt-containing fluids during the extension process.The presence of this weak layer makes it easier for strong earthquakes to occur through the release of overlying rigid crustal stresses.However,it is unlikely that an earthquake of comparable or larger magnitude would occur in the short term(e.g.,in one year)at the Jishishan east margin fault. 展开更多
关键词 Jishishan M_(s)6.2 earthquake crustal structure anisotropy stress and strain seismogenic mechanism northeast margin of the Tibetan Plateau
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SAFETY MARGIN CRITERION OF NONLINEAR UNBALANCE ELASTIC AXLE SYSTEM
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作者 陈予恕 李银山 薛禹胜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期621-630,共10页
The safety margin criterion of nonlinear dynamic question of an elastic rotor system are given. A series of observing spaces were separated from integral space by resolving and polymerizing method. The stable_state tr... The safety margin criterion of nonlinear dynamic question of an elastic rotor system are given. A series of observing spaces were separated from integral space by resolving and polymerizing method. The stable_state trajectory of high dimensional nonlinear dynamic systems was got within integral space.According to international standard of rotor system vibration, energy limits of safety criterion were determined. The safety margin was calculated within a series of observing spaces by comparative positive_area criterion (CPAC) method. A quantitative example calculating safety margin for unbalance elastic rotor system was given by CPAC. The safety margin criterion proposed includes the calculation of current stability margin in engineering. This criterion is an effective method to solve quantitative calculation question of safety margin and stability margin for nonlinear dynamic systems. 展开更多
关键词 unbalance elastic rotor safety margin comparative positive_area criterion (CPAC) bifurcation and chaos
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Stability margin of uncertain control systems
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作者 Bin LU Qinghe WU 《控制理论与应用(英文版)》 EI 2009年第4期427-432,共6页
Achieving stability is the essential issue in the control system design. In this paper, four approaches that can be used to calculate the stability margin of the interval plant family are summarized and compared. The ... Achieving stability is the essential issue in the control system design. In this paper, four approaches that can be used to calculate the stability margin of the interval plant family are summarized and compared. The μ approach gives the bounds of the stability margin, and good estimation can be obtained with the numerical method. The eigenvalue approach yields accurate value, and the MATLAB's function robuststab sometimes provides wrong results. Since the eigenvalue approach is both accurate and computationally efficient, it is recommended for the calculation of the stability margin, while utilization of the function robuststab should be avoided due to the unreliable results it gives. 展开更多
关键词 Interval plant family Stability margin Stability radius MATLAB's function robuststab
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Characteristics of Paleoproterozoic Subduction System in Western Margin of Yangtze Plate
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作者 Zhang Hongxiang Liu Congqiang Xu Zhifang Geology and Geophysics Institute, Chinese Academy of Sciences, Beijing 100101 Huang Zhilong Geochemistry Institute, Chinese Academy of Sciences, Guiyang 550002 《Journal of Earth Science》 SCIE CAS CSCD 2000年第1期58-67,共10页
Paleoproterozoic subduction strongly occurred in the western margin of Yangtze plate. The basalticandesite volcanics of Ailaoshan Group and Dibadu Formation had been formed during paleo QinghaiTibet oceanic plate s... Paleoproterozoic subduction strongly occurred in the western margin of Yangtze plate. The basalticandesite volcanics of Ailaoshan Group and Dibadu Formation had been formed during paleo QinghaiTibet oceanic plate subduction under the paleoYangtze plate. Their trace element geochemistry suggests that their forming environments are continentalmarginarc and back arcbasin respectively. Consequently, the Paleoproterozoic subduction system in the western margin of Yangtze plate was established. Ailaoshan Group and Dibadu Formation came from an enriched mantle source that was contaminated by crustal sediments carried by subducted slab, and formed the Paleoroterozoic metamorphic basement of western margin of Yangtze plate. Ailaoshan Group is actually western boundary of Yangtze plate. 展开更多
关键词 western margin of Yangtze plate Paleoproterozoic subduction system Ailaoshan Group (AG) Dibadu Formation (DF) incompatible element (IE) large ion lithospheric element (LILE) high field strengthen element (HFSE).
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A Radiotherapy Treatment Margin Formula When Systematic Positioning Errors are Relatively Small Compared to Random Positioning Errors: A First-Order Approximation
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作者 Kiyoshi Yoda 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第2期193-196,共4页
A radiotherapy treatment margin formula has been analytically derived when a standard deviation (SD) of systematic positioning errors &#425;is relatively small compared to an SD of random positioning errors &s... A radiotherapy treatment margin formula has been analytically derived when a standard deviation (SD) of systematic positioning errors &#425;is relatively small compared to an SD of random positioning errors &sigma;. The margin formula for 0 ≤ &#425;≤ &sigma;was calculated by linearly interpolating two boundaries at &#425;= 0 and &#425;= &sigma;, assuming that the van Herk margin approximation of k1&#425;+ k2&sigma;is valid at &#425;= &sigma;. It was shown that a margin formula for 0 ≤ &#425;≤ &sigma;may be approximated by k1&sigma;+ k2&#425;, leading to a more general form of k1 max(&#425;,&sigma;) + k2 min(&#425;,&sigma;) which is a piecewise linear approximation for any values of &#425;and &sigma;. 展开更多
关键词 TREATMENT margin systematic POSITIONING ERRORS RANDOM POSITIONING ERRORS
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Marginal discrepancy and microleakage in crown-copings fabricated by three CAD/CAM systems: An <i>in vitro</i>study
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作者 Marcela Herrera Alfonso Catalán +1 位作者 Maritza Flores Alejandra Martínez 《Open Journal of Stomatology》 2012年第3期163-169,共7页
The purpose of this study was to evaluate and compare the microleakage and marginal discrepancy of ceramic crown-copings fabricated by three different CAD/CAM systems. Material and methods: Thirty extracted premolars ... The purpose of this study was to evaluate and compare the microleakage and marginal discrepancy of ceramic crown-copings fabricated by three different CAD/CAM systems. Material and methods: Thirty extracted premolars were prepared for complete all-ceramic crowns with: total convergence 10-degree, 2 mm occlusal reduction, 4.5 mm height, 1.3 mm circular reduction and chamfer marginal preparation. They were divided into three groups and each group (n = 10) received a ceramic crown-coping fabricated by one of three CAD/CAM systems: Procera, KaVo Everest and Cerec inLab. The copings were cemented with Panavia F 2.0. After thermal cycling, the teeth were immersed in 2% basic fuchsine dye for 24 hours. Microleakage was scored using a five-point scale and evaluated under a stereomicroscope at ×18. Marginal discrepancies were assessed with scanning electronic microscope at ×150, with measurements at 50 different points. Data were subjected to a chisquare test, Kolmogorov-Smirnov test and using Rho Spearman’s correlation test (P 0.05). No significant differences were found in marginal discrepancies for the Procera (62.58 ± 8.98 μm) and KaVo Everest systems (65.54 ± 18.56 μm), (P = 0.941). Significant differences were found for Cerec inLab (132.18 ± 27.75 μm) compared with Procera and KaVo Everest (P = 0.0001). No correlation between the marginal discrepancies and microleakage for the three CAD/CAM crown-copings systems. Conclusions: Cerec inLab CAD/CAM crown-copings showed significantly higher values for microleakage and marginal discrepancy in comparison with Procera and KaVo Everest CAD/CAM crown-copings. 展开更多
关键词 CAD/CAM Copings MICROLEAKAGE marginAL DISCREPANCY Panavia F.2
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Marginal zone lymphoma with severe rashes: A case report
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作者 Si-Jun Bai Ye Geng +7 位作者 Yi-Nan Gao Cai-Xia Zhang Qian Mi Chen Zhang Jia-Ling Yang Si-Jie He Zhen-YingYan Jian-Xia He 《World Journal of Clinical Cases》 SCIE 2024年第3期565-574,共10页
BACKGROUND Marginal zone lymphoma(MZL)is an indolent subtype of non-Hodgkin lymphoma(NHL),which is rare clinically with severe rashes as the initial symptom.CASE SUMMARY This study reports a case of MZL with generaliz... BACKGROUND Marginal zone lymphoma(MZL)is an indolent subtype of non-Hodgkin lymphoma(NHL),which is rare clinically with severe rashes as the initial symptom.CASE SUMMARY This study reports a case of MZL with generalized skin rashes accompanied by pruritus and purulent discharge.First-line treatment with rituximab combined with zanubrutinib had poor effects.However,after switching to obinutuzumab combined with zanubrutinib,the case was alleviated,and the rashes disappeared.CONCLUSION For patients with advanced stage MZL not benefiting from type I anti-CD20 monoclonal antibody(mAb)combination therapy,switching to a type II anti-CD20 mAb combination regimen may be considered.This approach may provide a new perspective in the treatment of MZL. 展开更多
关键词 marginal zone lymphoma Mucosa-associated lymphoid tissue Extranodal marginal zone lymphoma Primary cutaneous marginal zone lymphoma Rituximab Obinutuzumab Zanubrutinib Case report
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The largest CPIES array in the marginal sea:abundant dynamics in the northeast South China Sea
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作者 Hua Zheng Xiao-Hua Zhu +4 位作者 Min Wang Ruixiang Zhao Chuanzheng Zhang Feng Nan Fei Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期135-137,共3页
The South China Sea(SCS)is a marginal sea connecting the Pacific and Indian oceans and has gained much attention in recent decades.The dynamics in the northeast SCS are considerably influenced by topography,monsoons,t... The South China Sea(SCS)is a marginal sea connecting the Pacific and Indian oceans and has gained much attention in recent decades.The dynamics in the northeast SCS are considerably influenced by topography,monsoons,tropical cyclones,the Kuroshio intrusion,and water exchange through the Luzon Strait(LS). 展开更多
关键词 NORTHEAST marginAL abundant
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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration
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作者 Jin-Min Song Xin Jin +10 位作者 Zhong Luo Shu-Gen Liu Shao-Bo Liu Xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期806-822,共17页
Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional p... Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. 展开更多
关键词 Sichuan Basin The Member Deng-2 marginal microbial mound-bank complex Depositional model Exploration implications
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Linkage between precipitation isotopes and water vapor sources in the monsoon margin:Evidence from arid areas of Northwest China
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作者 CHEN Fenli ZHANG Qiuyan +3 位作者 WANG Shengjie CHEN Jufan GAO Minyan Mohd Aadil BHAT 《Journal of Arid Land》 SCIE CSCD 2024年第3期355-372,共18页
The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is u... The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is usually sensitive to climate change.The water resource management in the monsoon margin should be better planned by understanding the composition of precipitation isotope and its influencing factors.In this study,the precipitation samples were collected at five sampling sites(Baiyin City,Kongtong District,Maqu County,Wudu District,and Yinchuan City)of the monsoon margin in the northwest of China in 2022 to analyze the characteristics of stable hydrogen(δD)and oxygen(δ18O)isotopes.We analyzed the impact of meteorological factors(temperature,precipitation,and relative humidity)on the composition of precipitation isotope at daily level by regression analysis,utilized the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)-based backward trajectory model to simulate the air mass trajectory of precipitation events,and adopted the potential source contribution function(PSCF)and concentration weighted trajectory(CWT)to analyze the water vapor sources.The results showed that compared with the global meteoric water line(GMWL),the slope of the local meteoric water line(LMWL;δD=7.34δ^(18)O-1.16)was lower,indicating the existence of strong regional evaporation in the study area.Temperature significantly contributed toδ18O value,while relative humidity had a significant negative effect onδ18O value.Through the backward trajectory analysis,we found eight primary locations that were responsible for the water vapor sources of precipitation in the study area,of which moisture from the Indian Ocean to South China Sea(ITSC)and the western continental(CW)had the greatest influence on precipitation in the study area.The hydrogen and oxygen isotopes in precipitation are significantly influenced by the sources and transportation paths of air mass.In addition,the results of PSCF and CWT analysis showed that the water vapor source areas were primarily distributed in the south and northwest direction of the study area. 展开更多
关键词 water vapor monsoon margin stable water isotope transport trajectory air mass d-excess Δ18O δD
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Distal margin distance in radical resection of locally advanced rectal cancer after neoadjuvant therapy
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作者 Jun Luo Mingxuan Zhu +6 位作者 Long Zhao Meiwen He Bei Li Yifan Liu Yuhan Sun Guoqing Lyu Zhanlong Shen 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第2期226-232,共7页
Colorectal cancer has a high incidence and mortality rate in China, with the majority of cases being middle and low rectal cancer. Surgical intervention is currently the main treatment modality for locally advanced re... Colorectal cancer has a high incidence and mortality rate in China, with the majority of cases being middle and low rectal cancer. Surgical intervention is currently the main treatment modality for locally advanced rectal cancer, with the common goal of improving oncological outcomes while preserving function. The controversy regarding the circumferential resection margin distance in rectal cancer surgery has been resolved. With the promotion of neoadjuvant therapy concepts and advancements in technology, treatment strategies have become more diverse.Following tumor downstaging, there is an increasing trend towards extending the safe distance of distal rectal margin. This provides more opportunities for patients with low rectal cancer to preserve their anal function.However, there is currently no consensus on the specific distance of distal resection margin. 展开更多
关键词 Colorectal cancer distal resection margin neoadjuvant therapy
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