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Zircon U-Pb dating of metagabbro masses from the Liwu Group Complex within the Taka dome:Geochronological constraints on the Indosinian-Yanshanian tectonic events in western Sichuan,China
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作者 Hong-chao Zhang Hong-bing Zhou +7 位作者 Bo Yan Chong-bo Sun Yue-zhong Wang Yun-chuan Zhao Yao Wen Ren-liang Cao Yang Qin Hong-qi Tan 《China Geology》 2025年第4期865-868,I0004-I0006,共7页
1.Objective The Songpan-Ganze terrane is a key region for understanding the tectonic evolution of the Tibetan Plateau and the Yangtze Craton.The Songpan-Ganzi complex comprises a thick succession of deformed Ladinian-... 1.Objective The Songpan-Ganze terrane is a key region for understanding the tectonic evolution of the Tibetan Plateau and the Yangtze Craton.The Songpan-Ganzi complex comprises a thick succession of deformed Ladinian-Norian turbidites(ca.230-203 Ma),covering about 200000 km^(2)of the eastern Tibet Plateau with a volume of approximately 2.0×10^(6)km^(3)(Fig.1a).Furthermore,this complex has over 100 Permian-Cenozoic felsic plutons. 展开更多
关键词 u pb dating INDOSINIAN zircon METAGABBRO taka dome YANSHANIAN liwu group complex tectonic events
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Lie Groups Actions on Non Orientable <i>n</i>-Dimensional Complex Manifolds 被引量:3
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作者 T. Cao-Huu D. Ghisa 《Advances in Pure Mathematics》 2021年第6期604-610,共7页
Analytic atlases on <img src="Edit_948e45b7-cbef-425e-bb79-28648b859994.png" width="23" height="22" alt="" /> can be easily defined making it an n-dimensional complex mani... Analytic atlases on <img src="Edit_948e45b7-cbef-425e-bb79-28648b859994.png" width="23" height="22" alt="" /> can be easily defined making it an n-dimensional complex manifold. Then with the help of bi-M<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#246;bius transformations in complex coordinates Abelian groups are constructed making this manifold a Lie group. Actions of Lie groups on differentiable manifolds are well known and serve different purposes. We have introduced in previous works actions of Lie groups on non orientable Klein surfaces. The purpose of this work is to extend those studies to non orientable n-dimensional complex manifolds. Such manifolds are obtained by factorizing <img src="Edit_7e5721ee-bb7f-4224-bd52-7d4641ac1c73.png" width="23" height="22" alt="" /> with the two elements group of a fixed point free antianalytic involution of <img src="Edit_ddfdac64-b296-48c5-9bb2-932eb3d76008.png" width="23" height="22" alt="" />. Involutions h(z) of this kind are obtained linearly by composing special M<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#246;bius transformations of the planes with the mapping <img src="Edit_4cda269a-9399-41ae-a5da-0c9d18a419ab.png" width="89" height="24" alt="" /><img src="Edit_4cda269a-9399-41ae-a5da-0c9d18a419ab.png" width="85" height="22" alt="" />. A convenient partition of <img src="Edit_9e899708-41b0-4351-a12b-cc6efb5b1581.png" width="23" height="22" alt="" /> is performed which helps defining an internal operation on <img src="Edit_7cd42987-68f8-4e4c-9382-cbc68b56377e.png" width="49" height="26" alt="" /> and finally actions of the previously defined Lie groups on the non orientable manifold <img src="Edit_5740b48c-f9ea-438d-a87d-8cdc1f83662b.png" width="49" height="25" alt="" /> are displayed. 展开更多
关键词 Analytic Atlas complex Manifold Möbius Transformation Lie group Action
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Group tracking algorithm for split maneuvering based on complex domain topological descriptions 被引量:1
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作者 Cong WANG Chen GUO +1 位作者 Yu LIU You HE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第1期126-136,共11页
A group tracking algorithm for split maneuvering based on complex domain topological descriptions is proposed for the tracking of members in a maneuvering group. According to the split characteristics of a group targe... A group tracking algorithm for split maneuvering based on complex domain topological descriptions is proposed for the tracking of members in a maneuvering group. According to the split characteristics of a group target, split models of group targets are established based on a sliding window feedback mechanism to determine the occurrence and classification of split maneuvering, which makes the tracked objects focus by group members effectively. The track of an outlier single target is reconstructed by the sequential least square method. At the same time, the relationship between the group members is expressed by the complex domain topological description method, which solves the problem of point-track association between the members. The Singer method is then used to update the tracks. Compared with classical multi-target tracking algorithms based on Multiple Hypothesis Tracking (MHT) and the Different Structure Joint Probabilistic Data Association (DS-JPDA) algorithm, the proposed algorithm has better tracking accuracy and stability, is robust against environmental clutter and has stable time-consumption under both classical radar conditions and partly resolvable conditions. 展开更多
关键词 complex domain group targets Joint probabitistic data association Multiple hypothesis tracking Sliding window feedback Tracking
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SYNTHESES,CHARACTERIZATION AND ETHYLENE POLYMERIZATION OF HALF-SANDWICH GROUP IV METAL COMPLEXES WITH TRIDENTATE [O,N,S] LIGANDS 被引量:1
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作者 Ya-lin Qiao Ping Hu 金国新 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第5期760-768,共9页
A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-((2-(SC6H5)C6H4N = CHC6H2O)]- (La) and dianionic phenoxy-amine arylsulfide [O... A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-((2-(SC6H5)C6H4N = CHC6H2O)]- (La) and dianionic phenoxy-amine arylsulfide [O-N-S] ligand [2-Bu^t4-Me-6-((2-(SC6H5)C6H4N-CH2C6H2O)]2- (Lb) have been synthesized and characterized. Lb was obtained easily in high yield by reduction of ligand La with excess LiAlH4 in cool diethyl ether. Half-sandwich Group Ⅳ metal complexes CpTi[O-NS]Cl2 (1a), CpZr[O-NS]Cl2 (1b), CpTi[O-N-S]Cl (2a), CpZr[O-N-S]Cl (2b) and CpZr[O-N-S]Cl (2c) were synthesized by the reactions of La and Lb with CpTiCl3, CpZrCl3 and Cp ZrCl3, and characterized by IR, ^1H-NMR, ^13C-NMR and elemental analysis. In addition, an X-ray structure analysis was performed on ligand Lb. The title Group IV half-sandwich bearing tridentate [O,N,S] ligands show good catalytic activities for ethylene polymerization in the presence of methylaluminoxane (MAO) as co-catalyst up to 1.58 × 10^7 g-PE.mol-Zr-1.h-1. The good catalytic activities can be maintained even at high temperatures such as 100 ℃ exhibiting the excellent thermal stability for these half-sandwich metal pre-catalysts. 展开更多
关键词 Half-sandwich group IV metal complexes Tridentate dianionic ligands Phenoxy-imine arylsulfide ligands Catalyst Ethylene polymerization
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A new understanding of Demala Group complex in Chayu Area, southeastern Qinghai- Tibet Plateau: Evidence from zircon U-Pb and mica ^(40)Ar/^(39)Ar dating 被引量:5
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作者 Yuan Tang Yu-ping Liu +5 位作者 Peng Wang Wen-qing Tang Ya-dong Qin Xiao-dong Gong Dong-bing Wang Bao-di Wang 《China Geology》 2021年第1期77-94,共18页
The Chayu area is located at the southeastern margin of the Qinghai-Tibet Plateau.This region was considered to be in the southeastward extension of the Lhasa Block,bounded by Nujiang suture zone in the north and Yarl... The Chayu area is located at the southeastern margin of the Qinghai-Tibet Plateau.This region was considered to be in the southeastward extension of the Lhasa Block,bounded by Nujiang suture zone in the north and Yarlung Zangbo suture zone in the south.The Demala Group complex,a set of high-grade metamorphic gneisses widely distributed in the Chayu area,is known as the Precambrian metamorphic basement of the Lhasa Block in the area.According to field-based investigations and microstructure analysis,the Demala Group complex is considered to mainly consist of banded biotite plagiogneisses,biotite quartzofeldspathic gneiss,granitic gneiss,amphibolite,mica schist,and quartz schist,with many leucogranite veins.The zircon U-Pb ages of two granitic gneiss samples are 205±1 Ma and 218±1 Ma,respectively,representing the ages of their protoliths.The zircons from two biotite plagiogneisses samples show core-rim structures.The U-Pb ages of the cores are mainly 644–446 Ma,1213–865 Ma,and 1780–1400 Ma,reflecting the age characteristics of clastic zircons during sedimentation of the original rocks.The U-Pb ages of the rims are from 203±2 Ma to 190±1 Ma,which represent the age of metamorphism.The zircon U-Pb ages of one sample taken from the leucogranite veins that cut through granitic gneiss foliation range from 24 Ma to 22 Ma,interpreted as the age of the anatexis in the Demala Group complex.Biotite and muscovite separates were selected from the granitic gneiss,banded gneiss,and leucogranite veins for 40Ar/39Ar dating.The plateau ages of three muscovite samples are 16.56±0.21 Ma,16.90±0.21 Ma,and 23.40±0.31 Ma,and the plateau ages of four biotite samples are 16.70±0.24 Ma,16.14±0.19 Ma,15.88±0.20 Ma,and 14.39±0.20 Ma.The mica Ar-Ar ages can reveal the exhumation and cooling history of the Demala Group complex.Combined with the previous research results of the Demala Group complex,the authors refer that the Demala Group complex should be a set of metamorphic complex.The complex includes not only Precambrian basement metamorphic rock series,but also Paleozoic sedimentary rock and Mesozoic granitic rock.Based on the deformation characteristics,the authors concluded that two stages of the metamorphism and deformation can be revealed in the Demala Group complex since the Mesozoic,namely Late Triassic-Early Jurassic(203–190 Ma)and Oligocene–Miocene(24–14 Ma).The early stage of metamorphism(ranging from 203–190 Ma)was related to the Late Triassic tectono-magmatism in the area.The anatexis and uplifting-exhumation of the later stage(24–14 Ma)were related to the shearing of the Jiali strike-slip fault zone.The Miocene structures are response to the large-scale southeastward escape of crustal materials and block rotation in Southeast Tibet after India-Eurasia collision. 展开更多
关键词 Demala group complex Zircon U-Pb dating 40Ar/39Ar dating Jiali fault zone Geological survey engineering Tibet-Qinghai Plateau China
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Octa-membered Water Ring Chain Based on Sulfonic Group in Ni(II) Complex with 2-[(E)-(2-Oxidophenyl)methyleneamino] Ethanesulfonato and 2,2′-Bipyridinyl 被引量:2
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作者 张淑华 李光照 +1 位作者 钟凡 冯小珍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1491-1494,共4页
The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983... The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983(18), b = 17.6929(15), c = 17.0897(15) nm, V= 6167.8(9) nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F(000) = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group. 展开更多
关键词 II Octa-membered Water Ring Chain Based on Sulfonic group in Ni Bipyridinyl complex with 2 Ethanesulfonato and 2 2 Oxidophenyl)methyleneamino
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Synthesis, Characterization and Biological Activity of Sodium Barbitone-Group-VIII Metals (viz. Ni(II), Pd(II) and Pt(II)) Complexes 被引量:1
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作者 Fatma S. M. Hassan Wafaa S. Kuran +1 位作者 Asmaa A. Ibrahim Farouk A. Adam 《Open Journal of Inorganic Non》 2020年第1期1-14,共14页
<span style="font-family:Verdana;">This work aims to characterize, synthesize and evaluate the biological activity of sodium barbitone and their metal chelates Ni(II), Pd(II) and Pt(II). The new synthe... <span style="font-family:Verdana;">This work aims to characterize, synthesize and evaluate the biological activity of sodium barbitone and their metal chelates Ni(II), Pd(II) and Pt(II). The new synthesized metal chelates are investigated by elemental analysis, IR, mass spectra, thermal analysis and biological activity. Square planer structure of the prepared complexes obtained from the result of analysis. The antibacterial and antifungal of sodium barbitone ligand and its conforming metal chelates were screened against bacterial species Gram positive (Staphylococcus aureus), Gram negative bacteria (Escherichia coli) and fungi Aspergillus flavus and Candida albicans fungi. Ampicillin and amphotericin were used as references for antibacterial and antifungal studies. The activity data show that the plati<span style="font-family:Verdana;">num group metals chelates have activity data show that some of the platinum group metals (viz. Pt(II) and Pd(II)) chelates have a promising biological activity comparing to sodium barbitone parent free ligand against bacterial and fungal species. 展开更多
关键词 Sodium Barbitone group VIII Metals Transition Metals complexes Spectroscopic Analyses Thermal Analysis Biological Activity
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Discovery of Paleogene Sporopollen from the Matrix Strata of the Naij Tal Group-Complex in the Eastern Kunlun Orogenic Belt 被引量:6
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作者 GUO Xianpu WANG Naiwen DING Xiaozhong ZHAO Min WANG Daning 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期490-497,共8页
The Naij Tai Group-complex is a suite of tectonic-sedimentary méiange aggregation of the Eastern Kunlun orogenic belt, which is composed of two parts, i.e. the exotic blocks of various ages and the matrix strata.... The Naij Tai Group-complex is a suite of tectonic-sedimentary méiange aggregation of the Eastern Kunlun orogenic belt, which is composed of two parts, i.e. the exotic blocks of various ages and the matrix strata. On the basis of coral, brachiopod and gastropod fossils found in the exotic blocks, the age of this group-complex was once defined to the Late Ordovician or the Paleozoic. This paper reports for the first time 44 genera and 31 species of Mid-Late Oiigocene sporopoilen in samples from the matrix strata in this group-complex and the Paleogene Quercoidites-Persicarioipollis assemblage is named. The paper aims to provide some detailed evidence for determining the age of the matrix strata in this group-complex based upon a study at the Caiyuanzigou section, which would be of great geological significance for further understanding this group-complex as a suite of tectonic-sedimentary méiange aggregation. The new finding will certainly benefit from now on the investigation of formation and evolution mechanism for the Eastern Kunlun orogenic belt. 展开更多
关键词 Naij Tai group-complex PALEOGENE sporopoilen méiange aggregation Eastern KunlunIt Orogenic Belt
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Synthesis of novel 1:2 Fe-complexed dye containing polyamine groups 被引量:1
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作者 Lei Yun Zhou Bing Tao Tang Shu Fen Zhang Jin Zong Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1296-1298,共3页
A Fe-complexed dye containing crosslinkable polyamine groups was synthesized through diazotization and coupling reaction, chlorination, amination and metallization. The structure of the Fe-complexed crosslinking dye w... A Fe-complexed dye containing crosslinkable polyamine groups was synthesized through diazotization and coupling reaction, chlorination, amination and metallization. The structure of the Fe-complexed crosslinking dye was characterized by FT-IR and Atomic Absorption Spectroscopic techniques. The dyeing and light fastness properties of the Fe-complex on silk and wool were tested, and the results showed that the novel Fe-complex exhibited both high fixation and good light fastness. 展开更多
关键词 Crosslinking dye Fe-complexed dye Polyamine groups Light fastness
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HOLOMORPHIC HARMONIC ANALYSIS ON COMPLEX REDUCTIVE GROUPS
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作者 安金鹏 钱敏 王正栋 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期560-572,共13页
The authors define the holomorphic Fourier transform of holomorphic functions on complex reductive groups, prove some properties such as the Fourier inversion formula, and give some applications. The definition of the... The authors define the holomorphic Fourier transform of holomorphic functions on complex reductive groups, prove some properties such as the Fourier inversion formula, and give some applications. The definition of the holomorphic Fourier transform makes use of the notion of K-admissible measures. The authors prove that K-admissible measures are abundant, and the definition of holomorphic Fourier transform is independent of the choice of K-admissible measures. 展开更多
关键词 complex reductive group Fourier transform holomorphic representation
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Recognition of Group Activities Using Complex Wavelet Domain Based Cayley-Klein Metric Learning
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作者 Gensheng Hu Min Li +2 位作者 Dong Liang Mingzhu Wan Wenxia Bao 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期592-603,共12页
A group activity recognition algorithm is proposed to improve the recognition accuracy in video surveillance by using complex wavelet domain based Cayley-Klein metric learning.Non-sampled dual-tree complex wavelet pac... A group activity recognition algorithm is proposed to improve the recognition accuracy in video surveillance by using complex wavelet domain based Cayley-Klein metric learning.Non-sampled dual-tree complex wavelet packet transform(NS-DTCWPT)is used to decompose the human images in videos into multi-scale and multi-resolution.An improved local binary pattern(ILBP)and an inner-distance shape context(IDSC)combined with bag-of-words model is adopted to extract the decomposed high and low frequency coefficient features.The extracted coefficient features of the training samples are used to optimize Cayley-Klein metric matrix by solving a nonlinear optimization problem.The group activities in videos are recognized by using the method of feature extraction and Cayley-Klein metric learning.Experimental results on behave video set,group activity video set,and self-built video set show that the proposed algorithm has higher recognition accuracy than the existing algorithms. 展开更多
关键词 video surveillance group activity recognition non-sampled dual-tree complex wavelet packet transform(NS-DTCWPT) Cayley-Klein metric learning
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The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group
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作者 REN Guang-zhen SHI Yun KANG Qian-qian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期181-190,共10页
The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,respectively.I... The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,respectively.In this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex Heisenberg.We investigate quaternionic analysis on the generalized complex Heisenberg.We also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex. 展开更多
关键词 the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula
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Coordination equilibrium between cyclometalated Pt(Ⅱ)complexs[Pt(κ^(3)-N^C^N′)(CNXyl)]Cl and[Pt(κ^(2)-N^C^N′)(CNXyl)Cl] 被引量:1
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作者 ZHANG Huahong ZHAO Yang +2 位作者 NING Rui WU Shuixing ZHANG Xiaopeng 《无机化学学报》 北大核心 2025年第9期1840-1850,共11页
Reaction of the non-substituted/substituted unsymmetric pinene-derived complex[Pt(N^C^N')Cl]with the aryl isocyanide 2,6-dimethylphenyl isocyanide(CNXyl)afforded a mixture of two isomeric species:the ionic complex... Reaction of the non-substituted/substituted unsymmetric pinene-derived complex[Pt(N^C^N')Cl]with the aryl isocyanide 2,6-dimethylphenyl isocyanide(CNXyl)afforded a mixture of two isomeric species:the ionic complex[Pt(κ^(3)-N^C^N')(CNXyl)]Cl([A]Cl)and the molecular complex[Pt(κ^(2)-N^C^N')(CNXyl)Cl](B).Isomer B was almost the dominating product.The structures of the isomer B derivatives bearing-CF_(3)and-Cl substituents on the pyridine ring of the pinene moiety(5B and 7B,respectively)have been confirmed by single-crystal X-ray diffraction,revealing a slightly distorted square planar geometry with trans-N_(N^C^N'),CNR configuration(The terminal N atom of theκ^(2)-N^C^N'ligand is trans to the isocyanide ligand CNXyl.).Isomer B is thermodynamically more stable,as confirmed by theoretical calculations.CCDC:2416415,5B;2416414,7B. 展开更多
关键词 coordination equilibrium cyclometalated Pt(Ⅱ)complex isocyanide pinene group
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Contrastive Studies on Theories of Chinese Complex Sentences, Sentence Group and the SDRT
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作者 Gao Yun 《学术界》 CSSCI 北大核心 2013年第9期281-287,共7页
Theories of Chinese complex sentences and sentence groups refer to the research of complex sentences and sentence groups in modern Chinese. The SDRTrefers to a dynamic semantic theory of discourse interpretation propo... Theories of Chinese complex sentences and sentence groups refer to the research of complex sentences and sentence groups in modern Chinese. The SDRTrefers to a dynamic semantic theory of discourse interpretation proposed in 1990s by Asher.Through contrastive studies on theories of Chinese complex sentences,sentence groups and the SDRT,we find that they have much in common. 展开更多
关键词 中国 子集 动态语义 句子
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Discussion on the Complex Structure of Nilpotent Lie Groups Gk
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作者 Caiyu Du Yu Wang 《Open Journal of Applied Sciences》 2024年第6期1401-1411,共11页
Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent... Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent Lie group Gk, defined by the nilpotent Lie algebra g/ak, where g is the Lie algebra of G, and ak is an ideal of g. Then, J gives rise to an almost complex structure Jk on Gk. The main conclusion obtained is as follows: if the almost complex structure J of a nilpotent Lie group G is nilpotent, then J can give rise to a left-invariant integrable almost complex structure Jk on the nilpotent Lie group Gk, and Jk is also nilpotent. 展开更多
关键词 Almost complex Structure Nilpotent Lie group Nilpotent Lie Algebra
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Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),a new burbankite mineral from carbonatite-syenite complex in Shaxiongdong,Hubei,China
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作者 Jie Dai Xiao-dong Pan +10 位作者 Tong Wang Guo-wu Li Guan Wang Shang-ke Xie Jing Ren Kun-yang Wang Ting Li Tao Wang Jia-le He Jin-sha Xu Gan-fu Shen 《China Geology》 2025年第4期797-805,共9页
Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),is a new mineral species from Shaxiongdong,Hubei Province,China.It mainly occours as conchoidal crystals and with combination of hexagonal prism and pyramid and is associated with... Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),is a new mineral species from Shaxiongdong,Hubei Province,China.It mainly occours as conchoidal crystals and with combination of hexagonal prism and pyramid and is associated with calcite,K-feldspar,albite,aegirine,apatite,and ancylite-(Ce)(?)and strontianite etc.Lishiite is brittle with conchiform fracture and has a Mohs hardness of approximately 4 and none cleavages were observed.The Vickers microhardness(VHN10)is 197.42 kg/mm^(2)(range:166.88 kg/mm^(2) to 214.58 kg/mm^(2)),and the calculated density of lishiite is 3.696 g/cm3.Hand specimen of lishiite are yellow-brown.The empirical chemical formula of the lishiite is ^(A)(Ca_(1.18)Sr_(0.25)Na_(0.19□1.38))_(Σ3.00)^( B)[Sr_(2.17)(Ce_(0.42)La_(0.24)Nd_(0.09)Eu_(0.01))_(Σ0.76) Ba_(0.07)]_(Σ3.00)(C_(5.05)O_(15)).As a member of the burbankite group,the general formula of lishiite follows the general formula A_(3)B_(3)(CO_(3))_(5),where A=Na,Ca,or and B=Sr,Ba,REE,or Ca.Its crystal structure is hexagonal(space group P6_(3)mc)with unit cell parameters a=10.4898(5)Å,c=6.4167(5)Å,and V=611.47(6)Å^(3),characterized by layers of AO_(8) and BO_(10) polyhedra connected to[CO_(3)]^(3−)groups.The discovery of lishiite provides new insights into the evolutionary history of rare earth element(REE)carbonate deposit formation. 展开更多
关键词 Lishiite (Ca_(2)□)Sr_(3)(CO_(3))_(5) New mineral species Burbankite group Carbonatite-syenite complex Mineral exploration engineering Shaxiongdong
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天然棕色棉对亚铁离子的吸附行为
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作者 刘磊 刘海峰 +2 位作者 刘懿丹 马明波 周文龙 《现代纺织技术》 北大核心 2026年第1期67-75,共9页
为了探究天然棕色棉对Fe(Ⅱ)离子的吸附机制,采用硫酸亚铁铵来提供Fe(Ⅱ)离子,探讨了反应时间、吸附反应环境温度及溶液中Fe(Ⅱ)离子初始质量浓度对棕棉坯布吸附Fe(Ⅱ)离子特性的影响。利用傅里叶红外光谱、X射线光电子能谱、颜色特征... 为了探究天然棕色棉对Fe(Ⅱ)离子的吸附机制,采用硫酸亚铁铵来提供Fe(Ⅱ)离子,探讨了反应时间、吸附反应环境温度及溶液中Fe(Ⅱ)离子初始质量浓度对棕棉坯布吸附Fe(Ⅱ)离子特性的影响。利用傅里叶红外光谱、X射线光电子能谱、颜色特征值等表征,分析了棕棉坯布对Fe(Ⅱ)离子的吸附机理。结果表明:棕棉坯布吸附Fe(Ⅱ)离子的动力学符合拟二级动力学方程模型(R^(2)=0.9994),且升温有利于吸附作用的进行;等温吸附特征可较好地用Langmuir模型描述(R^(2)=0.9998),属于化学吸附;Fe(Ⅱ)离子与棕棉色素中的原花青素上的酚羟基发生络合反应,生成原花青素-Fe^(2+)络合物,并部分氧化为原花青素-Fe^(3+)络合物,两者共同作用使棕棉颜色加深,绿光和蓝光增强,且明度和饱和度下降。研究结果可为天然棕色棉的Fe(Ⅱ)离子增深固色整理工艺提供一定的理论参考。 展开更多
关键词 天然棕色棉 硫酸亚铁铵 吸附行为 络合 酚羟基
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氨曲南联合头孢他啶/阿维巴坦对碳青霉烯耐药阴沟肠杆菌复合群抗菌活性研究
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作者 梁亮 叶报春 +3 位作者 潘子安 陈家坚 温卓莲 谢丽 《河北医学》 2026年第2期329-335,共7页
目的:评估氨曲南(Aztreonam,ATM)联合头孢他啶/阿维巴坦(Ceftazidime/avibactam,CZA)对碳青霉烯耐药阴沟肠杆菌复合群(Carbapenem-resistant Enterobacter cloace comples,CRECC)的体外抗菌活性,分析CRECC中碳青霉烯酶的产生情况及其基... 目的:评估氨曲南(Aztreonam,ATM)联合头孢他啶/阿维巴坦(Ceftazidime/avibactam,CZA)对碳青霉烯耐药阴沟肠杆菌复合群(Carbapenem-resistant Enterobacter cloace comples,CRECC)的体外抗菌活性,分析CRECC中碳青霉烯酶的产生情况及其基因型分布。方法:从2021年至2023年间收集本地区46株CRECC菌株。采用微量肉汤稀释棋盘法评估ATM和CZA的联合抗菌效果,并根据部分抑菌浓度指数(Fractional Inhibitory Concentration,FIC)判断药物的作用类型。通过改良碳青霉烯灭活试验(Modified Carbapenem Inactivation Method,mCIM)和EDTA改良碳青霉烯灭活试验(EDTAmodified Carbapenem Method,eCIM))确认菌株是否产碳青霉烯酶并初步区分A类、B类碳青霉烯酶,结合免疫层析法进一步明确碳青霉烯酶基因分布。结果:46株CRECC,ATM与CZA联合用药在39株菌株中表现为协同作用(FIC≤0.5),在7株菌株中表现为相加作用(0.5<FIC≤1),未发现无关作用或拮抗作用。ATM的最小抑菌浓度(Minimum inhibitory concentration,MIC)从256mg/L显著降低至0.008mg/L,降低了32000倍;CZA的MIC从64mg/L降低至0.015mg/L,降低了4,267倍。碳青霉烯酶基因型分析确认46株CRECC菌株中有38株菌株产NDM型碳青霉烯酶(占82.61%),8株菌株不产碳青霉烯酶(占17.39%)。ATM与CZA联合用药在38株产酶菌株中表现为协同作用(31株,占81.58%)或相加作用(7株,占18.42%),8株不产酶CRECC菌株,均表现为协同作用。结论:本地区流行的CRECC主要产NDM型碳青霉烯酶。ATM与CZA的联合用药对CRECC表现出显著的体外抗菌活性。该联合用药方案在抗击CRECC方面显示出良好的潜力。未来需要进一步研究其临床应用效果及安全性,以优化治疗策略。 展开更多
关键词 碳青霉烯耐药阴沟肠杆菌复合群 微量棋盘稀释法 碳青霉烯酶基因型 协同抗菌活性 氨曲南 头孢他啶/阿维巴坦
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U-Pb Zircon Dating of the Granitic Conglomerates of the Hutuo Group:Affinities to the Wutai Granitoids and Significance to the Tectonic Evolution of the Trans-North China Orogen 被引量:15
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作者 Jian ZHANG Guochun ZHAO +4 位作者 LI Sanzhong Min SUN LIU Shuwen Xiaoping XIA Yanhong HE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期886-898,共13页
The Wutai Complex associated with the adjacent Fuping and Hengshan Complexes represents the best and dassical cross-section in the middle segment of the Trans-North China Orogen, generally divided into Eastern and Wes... The Wutai Complex associated with the adjacent Fuping and Hengshan Complexes represents the best and dassical cross-section in the middle segment of the Trans-North China Orogen, generally divided into Eastern and Western Blocks. Unconformably overlying the Wutai and Fuping Complexes is the Hutuo Group considered as the youngest lithostratigraphic unit in the region and important both for interpreting Precambrian history as well as the overall evolution of the Trans-North China Orogen. Lack of knowledge about provenance of the sedimentary rocks in this group has hindered understanding of the depositional environments and tectonic significance. LA-ICP-MS was applied to obtain U-Pb zircon ages for the granitic pebbles, the lowest lithostratigraphic rock of the Hutuo Group, which, combined with previous lithostratigraphic, geochronological, structural and metamorphic data, provides new constraints on the sedimentary provenance and tectonic evolution of the region. The sequence of the Hutuo Group ranges upward from lower basal conglomerates and volcaniclastic rocks (Doucun Subgroup), through clastic sediments, slates, dolomites and marbles (Dongye Subgroup), to sandstones and conglomerates at the top (Guojiazhai Subgroup). Zircons from granitic pebbles preserved in the Doucun Subgroup basal conglomerates give weighted mean ^207pb/^206pb ages between 2517 Ma and 2566 Ma, which are the same as those for the late Archean Wutai Granitoids, indicating that the pebbles were derived from the Wutai granitic intrusions (2566-2515 Ma). Based on the new data and previous studies, combined with an igneous zircon crystallization age of 2087±9 Ma obtained for volcanics in the Hutuo Group, the Hutuo Group was deposited in a subduction-related retro-arc foreland basin environment that developed behind the Wutai arc during the eastward-directed subduction of the Western Block beneath the western margin of the Eastern Block. This basin underwent long-lived sedimentation and finally closed during the -1850 Ma collisional event that resulted in the final amalgamation of the North China Craton. 展开更多
关键词 Trans-North China Orogen PALEOPROTEROZOIC Wutai complex Hutuo group CONGLOMERATES
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Synthesis, Structure and Physical Properties of a Barium(II) Complex with 5-Sulfoisophthalic Acid Sodium 被引量:9
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作者 吴刚 王小锋 +1 位作者 韦昊 刘振锋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第8期1095-1100,共6页
An alkaline earth metal-organic framework [Ba(Hsip)(H2O)4]n (1, NaH2sip = 5-sulfoisophthalic acid sodium) has been constructed, and characterized by single-crystal X-ray diffraction. In complex 1, each Ba(II) ... An alkaline earth metal-organic framework [Ba(Hsip)(H2O)4]n (1, NaH2sip = 5-sulfoisophthalic acid sodium) has been constructed, and characterized by single-crystal X-ray diffraction. In complex 1, each Ba(II) atom coordinates to one ligand Hsip3- and four water molecules with a distorted nine-coordinated monocapped tetragonal antiprism geometry. Each Hsip2- anion acts as a μ3-bridging ligand, in which two carboxylate groups adopt the same bidentate chelating coordinating model and the sulfonate group takes a monodentate coordinating model, resulting in a wave-like two-dimensional network with a (6, 3) topological structure. The two-dimensional networks are further linked by O–H···O to form a three-dimensional structure. Luminescent property and thermal stability of complex 1 are investigated. 1 belongs to the orthorhombic system, space group Pna21 with a = 7.3333(2), b = 16.7044(3), c = 10.4817(2), Z = 4, V = 1283.99(5)3, Mr = 453.58, Dc = 2.346 g/cm3, F(000) = 880, μ = 3.314 mm–1, the final R = 0.0261 and wR = 0.0592 for 2425 observed reflections with I 2σ(I). 展开更多
关键词 Ba(II) complex sulfonate group carboxylate group luminescent property thermal stability
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