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Comparative Analysis of Sequence Characteristics among Different Superimposed Stages of the Chelif Basin,Algeria 被引量:4
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作者 ZHANG Yuanfu JIANG Zaixing WANG Yue BAO Dandan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第6期1041-1051,共11页
Superimposed basins were investigated with respect to tectonic evolution, sediment deposition and petroleum characteristics within a single superposition stage generally. The comparative study was seldom seen. Sequenc... Superimposed basins were investigated with respect to tectonic evolution, sediment deposition and petroleum characteristics within a single superposition stage generally. The comparative study was seldom seen. Sequence characteristics were compared for two different superimposed stages - an expanding rifting stage and a depression-foreland transition stage - in the Chelif Basin during the Miocene in this paper. A model and mechanism for sequence evolution of superimposed basins in different dynamic situations are discussed with respect to sequence similarities and differences. The compared characters include sequence thickness, sequence boundaries and system tracts, as well as sediment deposition within sequences and sequence development patterns. Finally, some typical features of sequence development concomitant with changes of superimposed stages in the Chelif Basin are discussed. 展开更多
关键词 superimposed basin sequence characteristics sediment deposition structural dynamics petroleum accumulation
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Seismic Sequence Characteristics of the March 21,2008,M_S 7. 4 Yutian,Xinjiang Earthquake and Seismological Anomalies before the Earthquake
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作者 Nie Xiaohong Li Yingzhen 《Earthquake Research in China》 2012年第3期377-390,共14页
The parameters, stress field background, geological tectonics and seismic sequence of the March 21, 2008, Ms7.4 Yutian, Xinjiang earthquake are discussed in this paper. The characteristics of seismic activity in the e... The parameters, stress field background, geological tectonics and seismic sequence of the March 21, 2008, Ms7.4 Yutian, Xinjiang earthquake are discussed in this paper. The characteristics of seismic activity in the epicenter and its adjacent region before the earthquake are analyzed; and a comparison is made between the Ms7.4 Yutian earthquake sequence, the Wenchuan Ms8.0 earthquake sequence and the Wuqia Ms6.9 earthquake sequence. The results show the Ms7.4 Yutian earthquake occurred in the junction between the Aityn Tagh fault and the western Kunlun fault, resulting perhaps from the tensile fracture of the branch fault located southwest of the Ashikule basin due to left-lateral dislocation of the Aityn Tagh fault; the seismic sequence is of main shock-aftershock type, the strongest aftershock being Ms5.8. The aftershocks attenuated quickly, and occurred in groups; the focal mechanism solutions and epicenter distribution have revealed a unilateral rupture source of this earthquake. Seismic activity shows that there was medium and medium-short term abnormity before the earthquake, but there was not short-imminent abnormity. Seismic activity of this earthquake sequence enhanced before the Ms8. 0 Wenchuan and the Ms6. 9 Wuqia earthquakes, showing the window effect to some extent. 展开更多
关键词 Ms7.4 Yutian earthquake sequence characteristic Seismic activitycharacteristics Window effect
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A priliminary study on the sequence characteristics and focal mechanism solution of the Jiashi strong earthquake swarm 被引量:2
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作者 XIN YANG GUO YING GAO Seismological Bureau of Xinjiang Uygur Autonomous Region, rümqi 830011, China 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第6期16-23,共8页
The sequence characteristics and focal mechanism solution of the Jiashi, Xinjiang strong earthquake swarm are analyzed and studied in this paper. The result shows that before the M S=6.6 earthquake, value h o... The sequence characteristics and focal mechanism solution of the Jiashi, Xinjiang strong earthquake swarm are analyzed and studied in this paper. The result shows that before the M S=6.6 earthquake, value h of sequence frequency attenuation coefficient was less than 1, then value h was more than 1. Before occurrence of M S6.0 earthquakes the energy is released either in a continuously strengthened way or a sharply strengthened way, and before M S5.0 earthquakes the sequence frequency shows calm. The study on the focal mechanism solution of the strong earthquake swarm shows that the source faults are mainly in a right lateral, strike slip way and the faults have characteristics of tensor shear. 展开更多
关键词 earthquake swarm sequence characteristics focal mechanism SOLUTION focal displacement feature JIASHI
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Characteristic atom sequences of Nb-Mo alloys system in BCC structure and properties of disordered alloys
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作者 彭红建 武青 +1 位作者 李小波 谢佑卿 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1190-1196,共7页
Comprehensively considering energy, volume and electronic structure of alloys, the ninth equation was determined as the interaction function of Nb-Mo alloys system in BCC structure on the basis of idea of systematic s... Comprehensively considering energy, volume and electronic structure of alloys, the ninth equation was determined as the interaction function of Nb-Mo alloys system in BCC structure on the basis of idea of systematic science of alloys, experimental lattice constants and heats of formation of disordered Nb(1-x)Mox alloys. The structural parameters and properties of Nb and Mo characteristic atoms sequences and corresponding characteristic crystals sequences were determined in Nb-Mo alloys system. The electronic structure and physical properties of disordered Nb(1-x)Mox alloys system were calculated according to concentration of characteristic atoms of disordered alloys. The change trend of physical properties is the same as that of electronic structure. 展开更多
关键词 Nb-Mo alloys system characteristic atom sequences disordered alloys properties
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Quick Trickle Permutation Based on Quick Trickle Characteristic Sequence
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作者 WangLi-na FeiRu-chun LiuZhu 《Wuhan University Journal of Natural Sciences》 CAS 2003年第04A期1065-1069,共5页
The concept of quick trickle characteristic sequence is presented, the properties and count of quick trickle characteristic sequence are researched, the mapping relationship between quick trickle characteristic sequen... The concept of quick trickle characteristic sequence is presented, the properties and count of quick trickle characteristic sequence are researched, the mapping relationship between quick trickle characteristic sequence and quick trickle permutation is discussed. Finally, an efficient construction of quick trickle permutation based on quick trickle characteristic sequence is given, by which quick trickle permutation can be figured out after constructing quick trickle characteristic sequence. Quick trickle permutation has good cryptographic properties. 展开更多
关键词 quick trickle characteristic sequence quick trickle characteristic mapping quick trickle permutation
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Tracing the Forecast of Earthquakes Based on the Seismicity Characteristics of the Chi-Chi Strong Earthquake Swarm Sequence
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作者 Cheng KueihsiangIntegrated Research Laboratory on Prediction of Seismic Hazard, The Department of Civil Engineering, Kao Yuan Institute of Technology, Kaohsiung, Taiwan (China) 《Earthquake Research in China》 2003年第1期85-96,共12页
The data of earthquakes with M ≥3 0 during the 7 years from September 21, 1993 to September 20, 2000 recorded by the Taiwan Central Weather Bureau (CWB) show that there were 6 types of clear characteristics of seismi... The data of earthquakes with M ≥3 0 during the 7 years from September 21, 1993 to September 20, 2000 recorded by the Taiwan Central Weather Bureau (CWB) show that there were 6 types of clear characteristics of seismicity during the Chi Chi strong earthquake swarm of September 21 These 6 types of characteristics are (1) foreshock types, (2) seismic gaps, (3) seismic bands, (4) clustering activity of foreshocks and signal shock, (5) quiescence before the main shock and (6) secondary aftershocks in the aftershock sequence. Using the procedures for analyzing the yearly strong earthquake tendency, further tracing based on the earthquake sequence characteristics, and taking the Chi Chi earthquake sequence as an example, tracing analysis of the earthquake tendency was attempted using the shorter time range of monthly rather than in a yearly time scale. An attempt was made to establish the procedures for tracing analysis of shallow focus earthquakes in the seismic belt of western Taiwan. It is hoped that this can provide an analystical method for approaching the short imminent time scale of seismometry based earthquake forecasting. 展开更多
关键词 Seismicity characteristics of earthquake sequence Earthquake tendency analysis Tracing forecast of earthquakes
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Sequence Stratigraphy of the Jurassic Coal Measures in Northwestern China 被引量:12
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作者 WANG Tong SHAO Longyi +2 位作者 TIAN Ye LU Jing WANG Wenlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第3期769-778,共10页
The sequence stratigraphy of the Jurassic coal measures of northwestern China has been studied based on data from outcrop and borehole sections. Because of the geological background and the diversity of basin types, s... The sequence stratigraphy of the Jurassic coal measures of northwestern China has been studied based on data from outcrop and borehole sections. Because of the geological background and the diversity of basin types, such as isochronisms of coal seams and recognition of key sequence boundaries, it is rare to summarize and correlate sequence structure and framework. The types and recognition characteristics of the sequence boundaries of the Jurassic coal measures are revealed by comparing climatic characteristics, structural styles and the base level cycle. A total of five third-order sequences and 15 systems tracts have been subdivided and the sequence stratigraphic framework has been reconstructed confirming that the thick coals accumulated in the late stage of transgression system tracts of sequence I (SQ I) and sequence III (SQ III). This idea is of important academic significance for instructing coal resources exploration, and enhancing geological effects of prospecting engineering. It is also of practical significance for guaranteeing construction of the large-scale coal production base in northwestern China, accelerating the westward development of the coal industry stratagem. 展开更多
关键词 depositional system sequence stratigraphic characteristics Jurassic (Hettangian–Callovian) coal basins northwestern China
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Mineralogical characteristics of polymetallic sulfides from the Deyin-1 hydrothermal field near 15°S, southern Mid-Atlantic Ridge 被引量:4
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作者 WANG Shujie LI Huaiming +3 位作者 ZHAI Shikui YU Zenghui SHAO Zongze CAI Zongwei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期22-34,共13页
A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development A... A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development Association(COMRA). Sulfide samples were collected at three stations from the hydrothermal field during the26 th cruise in 2012. In this paper, mineralogical characteristics of the sulfides were analyzed with optical microscope, X-ray diffractometer, scanning electron microscope and electron microprobe to study the crystallization sequence of minerals and the process of hydrothermal mineralization. According to the difference of the ore-forming metal elements, the sulfide samples can be divided into three types:(1) the Ferich sulfide, which contains mainly pyrite and chalcopyrite;(2) the Fe-Cu-rich sulfide consisting predominantly of pyrite, chalcopyrite and isocubanite, with lesser amount of sphalerite, marmatite and pyrrhotine; and(3) the Fe-Zn-rich sulfide dominated by pyrite, sphalerite and marmatite, with variable amounts of chalcopyrite, isocubanite, pyrrhotine, marcasite, galena and gratonite. Mineral precipitations in these sulfides are in the sequence of chalcopyrite(isocubanite and possible coarse pyrite), fine pyrite,sphalerite(marmatite), galena, gratonite and then the minerals out of the dissolution. Two morphologically distinct generations(Py-I and Py-II) of pyrite are identified in each of the samples; inclusions of marmatite tend to exist in the coarse pyrite crystals(Py-I). Sphalerite in the Fe-Zn-rich sulfide is characterized by a"chalcopyrite disease" phenomenon. Mineral paragenetic relationships and a wide range of chemical compositions suggest that the environment of hydrothermal mineralization was largely changing. By comparison, the Fe-rich sulfide was formed in a relatively stable environment with a high temperature, but the conditions for the formation of the Fe-Cu-rich sulfide were variable. The Fe-Zn-rich sulfide was precipitated during the hydrothermal venting at relatively low temperature. 展开更多
关键词 mineralogical characteristics mineral-forming sequence polymetallic sulfides Deyin-1 hydrothermal field southern Mid-Atlantic Ridge
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Changes in source parameters of foreshocks and aftershocks of the 2001 M_S=6.0 Yajiang, Sichuan, earthquake 被引量:1
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作者 程万正 陈天长 +1 位作者 魏娅玲 朱航 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第4期371-381,共11页
In this paper changes in focal mechanisms, parameters of wave spectra, and stress drops for the MS=5.0 foreshock and MS=6.0 mainshock in February 2001 in Yajiang County, Sichuan, and seismicity in epicentral region ar... In this paper changes in focal mechanisms, parameters of wave spectra, and stress drops for the MS=5.0 foreshock and MS=6.0 mainshock in February 2001 in Yajiang County, Sichuan, and seismicity in epicentral region are studied. Comparison of focal mechanisms for the Yajiang earthquakes with distribution patterns of aftershocks, the nodal plane I, striking in the direction of NEN, of the Yajiang M=5.0 event is chosen as the faulting plane; the nodal plane II, striking in the direction of WNW, of the M=6.0 event as the faulting plane. The strikes of the two faulting planes are nearly perpendicular to each other. The level of stress drops in the epicentral region before the occurrence of the M=6.0 earthquake increases, which is consistent with increase of seismicity in the epicentral region. The rate decay of the Yajiang earthquake sequence, changes in wave spectra for foreshocks and aftershocks, and focal mechanisms are complex. 展开更多
关键词 Yajiang earthquake sequence characteristics source parameters
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Image Retrieval Based on Objects’ Spatial Orientation Relationships
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作者 CHENChuan-bo LIQi-shen GONGWen-jie 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第3期520-524,共5页
A new concept of characteristic scanning radial (CSR) is proposed for thesegmented image on the basis of two shape-specific points of its shape-objects. Subsequently, twocharacteristic attribute sequences (CAS) of rel... A new concept of characteristic scanning radial (CSR) is proposed for thesegmented image on the basis of two shape-specific points of its shape-objects. Subsequently, twocharacteristic attribute sequences (CAS) of relative distance and relative direction are derived torepresent the spatial orientation relationships among objects of the image. A novel image retrievalalgorithm is presented using these two CASs. The proposed retrieval approach not only satisfies thetransformational invariance, butalso attains the quantitative comparison of matching. Experimentsidentify the effectiveness and efficiency of the algorithm adequately. 展开更多
关键词 image retrieval spatial relationship transformation invariant shape-specific point characteristic scanning radial characteristic attribute sequence
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Characterization and implications of prokaryotic ribosome-binding sites across species
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作者 Yanting Duan Xiaojuan Zhang +6 位作者 Weiji Zhai Jinpeng Zhang Jiawei Ren Xiaomei Zhang Guoqiang Xu Jinsong Shi Zhenghong Xu 《Systems Microbiology and Biomanufacturing》 2022年第4期676-684,共9页
The ribosome-binding site(RBS)in the 5′untranslated region is recognized by 16S rRNA to start translation and is an essential element of the gene expression system.RBSs have been widely applied in regulating gene exp... The ribosome-binding site(RBS)in the 5′untranslated region is recognized by 16S rRNA to start translation and is an essential element of the gene expression system.RBSs have been widely applied in regulating gene expression in various scenarios,including Gram-negative or Gram-positive bacteria.Here,we first rationally designed and constructed an RBS mutant library containing 66 RBSs.The strength of these RBSs in E.coli and C.glutamicum was characterized individually.The RBS strength spanned about 200 and 15 times in the two species,respectively.The strength of RBSs in C.glutamicum was generally lower than that of in E.coli.A total of 18 RBSs showed similar strength(within twofold differences)between the species in our study,and the correlation analysis of the strength of RBSs between E.coli and C.glutamicum(R^(2)=0.7483)revealed that these RBSs can be used across species.The sequence analysis revealed that the RBS region with two Ts stated was beneficial for RBS to function cross-species.The RBS characterized here can be used to precisely regulate gene expression in both hosts,and the characteristics of cross-species RBSs provide basic information for RBS rational design. 展开更多
关键词 RBS library Cross-species RBSs sequence characteristics Escherichia coli Corynebacterium glutamicum
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The Classification of Filiform Leibniz Superalgebras of Nilindex n+m 被引量:1
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作者 Sh.A.AYUPOV B.A.OMIROV A.Kh.KHUDOYBERDIYEV 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第2期171-190,共20页
In this work the classification of filiform Leibniz superalgebras of nilindex n + m, where n and m (m≠0) are dimensions of even and odd parts, respectively, is obtained.
关键词 Lie superalgebras Leibniz superalgebras NILPOTENCY characteristic sequence
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