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| 1 | SHRIMP zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha Group in Tibet显示文摘The Nyainqêntanglha Group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha Group, 10 km west of Nam Co in northern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (SHRIMP). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha Group is constrained by U-Pb age of 748±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha Group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the northern margin of the India shield. The inherited zircons from the tholetiite and granite give older 207Pb/206Pb ages from 947 to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time. | HU Daogong1, WU Zhenhan1, JIANG Wan1, SHI Yuruo2, YE Peisheng1 & LIU Qisheng1 1. Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China 2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing SHRIMP Centre, Beijing 100037, China | 2005 | Science China Earth Sciences2005，48，9： | 49 |
| 2 | Pure quantitative characterization of finite projective special unitary groups显示文摘We prove that each projective special unitary group G can be characterized using; only the set of element orders of G and the order of G. | 曹洪平 施武杰 | 2002 | Science China Mathematics2002，45，6： | 20 |
| 3 | Discovery of Radiolarian Fossils from the Aiketik Group at the Western End of the South Tianshan Mountains of Chinaand Its Implications显示文摘The Aiketik Group, distributed at the western end of the South Tianshan Mountains, China, is an important lithostratigraphic unit involved in the South Tianshan orogen. It is separated from the adjacent rocks by faults. Generally, the geologists ascribed it to the Upper Carboniferous according to Pseudostaffella sp., Profusulinella sp. and Fusulinella sp. found from the limestone and sandy limestone of Aiketik. Our radiolarian fossils were obtained from the chert samples collected from the Haladaok section located at the upper Tuoshihan River. The fossils mainly include Albaillella undulata Deflandre, Albaillella paradoxa Deflandre, Albaillella sp. aff. A. paradoxa Deflandre, Albaillella sp. cf. A. deflandrei Gourmelon, Albaillella sp., Albaillella excelsa Ishiga, Kito and Imoto (?), Belowea variabilis (Ormiston et Lane), Callella cf. C. parvispinosa Won, Entactinia cf. E. tortispina Ormiston et Lane, Entactinia aff. E. tortispina Ormiston et Lane, Entactinia variospina Won, Entactinia sp., Eostylodictya rota (Won), Latentifistula impella (Ormistone et Lane) (?), Latentifistula turgida Omiston et Lane, Latentifistulidae gen. et. sp. indet. and Polyentactinia cf. aranea Gourmelon. Among them, Albaillella excelsa Ishiga, Kito and Imoto (?) is a Late Permian species with some elements uncertain as there is only one poorly-preserved fossil of this species found so far. And two radiolarian assemblages can be identified from the other fossils. One is the early Early Carboniferous assemblage represented by Albaillella undulata Deflandre, Albaillella paradoxa and Albaillella sp. cf. A. deflandrei Gourmelon. And the other is the late Early Carboniferous assemblage represented by Eostylodictya rota (Won). This is the first discovery of radiolarian fossils in the Aiketik Group, also the first discovery of Late Permian radiolarian fossils in the South Tianshan Mountains. Meanwhile, this is the current westernmost sampling site of radiolarian fossils in the South Tianshan Mountains. | 李曰俊 王招明 吴浩若 黄智斌 谭泽金 罗俊成 | 2002 | Acta Geologica Sinica(English Edition)2002，76，2： | 15 |
| 4 | Time and tectonic setting of the Xixiang Group:Constraints from zircon U-Pb geochronology and geochemistry显示文摘The present paper reports the research development in the timing and tectonic setting of the Xixiang Group, northwestern margin of the Yangtze block. U-Pb concordant ages of (946+-18) Ma and (904+-18) Ma of zircons were obtained from the upper and lower units of the Xixiang volcanic succession, respectively. Elemental and Nd isotope characteristics show that the volcanic suite has the affinities of arc island magmatism as well as an evolution trend of tectonic setting from front-arc to back-arc. The volcanic rocks suffered from some extensive post-stage tectonothermal events, resulting in the resetting of their Rb-Sr isotopic system. | 凌文黎 高山 欧阳建平 张本仁 李惠民 | 2002 | Science China Earth Sciences2002，45，9： | 13 |
| 5 | Mordell-Weil groups and Selmer groups of twin-prime elliptic curves显示文摘Let E = Eσ : y2 = x(x + σp)(x + σq) be elliptic curves, where σ = ±1, p and q are primenumbers with p+2 = q. (i) Selmer groups S(2)(E/Q), S(φ)(E/Q), and S(φ)(E/Q) are explicitly determined,e.g. S(2)(E+1/Q)= (Z/2Z)2, (Z/2Z)3, and (Z/2Z)4 when p ≡ 5, 1 (or 3), and 7(mod 8), respectively. (ii)When p ≡ 5 (3, 5 for σ = -1) (mod 8), it is proved that the Mordell-Weil group E(Q) ≌ Z/2Z Z/2Z,symbol, the torsion subgroup E(K)tors for any number field K, etc. are also obtained. | 邱德荣 张贤科 | 2002 | Science China Mathematics2002，45，11： | 11 |
| 6 | New classes of domains with explicit Bergman kernel显示文摘We introduce two classes of egg type domains, built on general boundedsymmetric domains, for which we obtain the Bergman kernel inexplicit formulas. As an auxiliary tool, we compute the integralof complex powers of the generic norm on a bounded symmetricdomains using the well-known integral of Selberg. Thisgeneralizes matrix integrals of Hua and leads to a specialpolynomial with integer or half-integer coefficients attached toeach irreducible bounded symmetric domain. | Roos GUY | 2004 | Science China Mathematics2004，47，3： | 8 |
| 7 | Symmetry properties of Cayley graphs of small valencies on the alternating group A_5显示文摘The normality of symmetry property of Cayley graphs of valencies 3 and 4 on the alternating group A5 is studied. We prove that all but four such graphs are normal;that A5 is not 5-CI. A complete classification of all arc-transitive Cayley graphs on A5 of valencies 3 and 4 as well as some examples of trivalent and tetravalent GRRs of A5 is given. | XU Mingyao XU Shangjin | 2004 | Science China Mathematics2004，47，4： | 7 |
| 8 | Diagonal invariant ideals of Toeplitz algebras on discrete groups显示文摘Diagonal invariant ideals of Toeplitz algebras defined on discrete groups are introduced and studied. In terms of isometric representations of Toeplitz algebras associated with quasi-ordered groups, a character of a discrete group to be amenable is clarified. It is proved that when G is Abelian, a closed two-sided non-trivial ideal of the Toeplitz algebra defined on a discrete Abelian ordered group is diagonal invariant if and only if it is invariant in the sense of Adji and Murphy, thus a new proof of their result is given. | 许庆祥 | 2002 | Science China Mathematics2002，45，4： | 5 |
| 9 | Discovery of agglutinated foraminifers from the Longzhaogou Group in eastern Heilongjiang Province显示文摘The low diversity agglutinated foraminifers are recovered from the Qihulin Formation of the Longzhaogou Group in eastern Heilongjiang, China. The foraminiferal fauna consists of 9 species of 5 genera. The common members are Cribrostomoides nonioninoides (Reuss), Haplophragmoides concavus (Chapman), H. gigas minor Nauss. Although the diagnostic zonal taxa are absent in the agglutinated fauna, according to the global stratigraphic distribution of the above-mentioned species, and the associated Pseudohaploceras ammonite fauna, the foraminiferal fauna may be of a Barremian-Aptian (Early Cretaceous) age. | LI Gang & YU Shanmao1. State Key Laboratory of Paleobiology Stratigraphy, Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China 2.108th Coal-prospecting Team of Geological Bureau, NE China and Inner Mongolia Coal Company, Jixi 158100, China Correspondence should be addressed to Li Gang (email: gangli@nigpas.ac.cn) | 2004 | Science China Earth Sciences2004，47，2： | 5 |
| 10 | Geochemical characteristics of the metapelites from the Xingxingxia group in the Eastern Segment of the Central Tianshan:Implications for the provenance and paleoweathering显示文摘Metapelites from the Mesoproterozoic Xingxingxia group in the Eastern Segment of the Central Tianshan, Northwestern China, were analyzed for major and trace elements, includ-ing rare earth elements. Compared with post-Archean shales, the metapelites are enriched in Sr, Hf and Zr. The other elements are similar to the compositions of the Phanerozoic North American Shale Composite and the Post-Archean Australian average Shale (PAAS). The characteristics of Al2O3/TiO2, Cr/Zr, Cr/Th, Th/Sc and high Zr concentration suggest that these pelites could be derived from a significant proportion of felsic and a few proportion of participation of mafic mate-rials in nature. These rocks display highly fractionated REE patterns, and average (La/Yb)n = 18.6. Several samples have slightly negative Eu anomalies (Eu/Eu* = 0.7―0.84) in comparison with PAAS (Eu/Eu* = 0.65), indicating contribution from young immature materials. The low K2O/Al2O3 values of these metapelites suggest that their source materials could contain minimal alkali feldspar. In the A-CN-K triangular diagram, the sample data array intersects the feldspar join, indicating that the source had a plagioclase: K-feldspar ratio of approximately 5:1, repre-senting weathered products from components that could approximately correspond to granodio-rites and tonalites. The low Chemical Index of Alteration (CIA) and high Index of Compositional Variability (ICV) values suggest low degrees of weathering of the source and low compositional maturity of the sediments, respectively. The geochemical characteristics of the metapelites from the Xingxingxia group also demonstrate that these sediments were deposited in a back-arc background within a continental-arc system. | LI Qiugen LIU Shuwen HAN Baofu WANG Yueran DANG Qingning | 2005 | Science China Earth Sciences2005，48，10： | 4 |
| 11 | Studies on the Surface Properties of MCM-41显示文摘MCM 41 materials with a well ordered long range structure, a large pore size and a high surface area have been synthesized. Their surface properties including the number and the nature of the surface hydroxyl groups and surface hydrophobicity/hydrophilicity have been investigated by means of 29 Si MAS NMR and FT IR spectra and TPD of probe molecules. The results clearly show that the surface of MCM 41 has an abundance of acidic silanol groups, and that the hydrophobicity/hydrophilicity can be modified by the introduction of Al and transition metals Ti, Cr, Ni and Fe into it. | HE Jing, DUAN Xue ** , EVANS D. G. and LI Cheng yue The Key Laboratory of Science and Technology of Controllable Chemical Reactions, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, P.R.China | 2002 | Chemical Research in Chinese Universities2002，18，3： | 4 |
| 12 | Geochemical characteristics of Bikou volcanic group and Sr-Nd-Pb isotopic composition: Evidence for breakup event in the north margin of Yangtze plate, Jining era显示文摘The geodynamic setting of the Bikou volcanic group is a critical question to trace the Precambrain tectonic framework and evolution for the Yangtze plate. This study has suggested that the Bikou volcanic group is composed of several residual oceanic crust units: MORB (mid-ocean ridge basalt), Alk-OIB (alkaline ocean island basalt) and Th-OIB (tholeiitic ocean island basalt) as well as subduction-related volcanic rocks. According to field observation, those distinct rocks occurred collectively in form of tectonic contact, implying that the Bikou volcanic group was an ophiolitic mélange. Coupled with geochronological data, a perished oceanic basin at the northern margin of the Yangtze block during Neoproterozoic was tested by this ophiolitic mélange. Meanwhile, the isogeochemical data suggest that the ocean occurred in the Southern Hemisphere identical to Indian, South Atlantic and South Pacific oceans in terms of their Dupal anomalies, and the original source of the rocks could be probably mixing by EMⅠand EMⅡ component caused by dehydration melting of subducting oceanic crust during subduction process. On the basis of geochemical characteristics of the studied rocks, the Bikou volcanic group could imply that a partial breakup event occurred in the northern margin of Yangtze plate during the Neoproterozoic era. | LI YongFei LAI ShaoCong QIN JiangFeng LIU Xin WANG Juan | 2007 | Science China Earth Sciences2007，50，z2： | 4 |
| 13 | The Caledonian low Al-TTD series from the Northern Qinling Orogenic Belt:Rock properties,genetic simulation and geological implication显示文摘A belt of low Al-Trondhjemite-Tonalite-Diorite (TTD) series has been recognized along the Northern Qinling Orogenic Belt (NQOB), which is dated as 430―399 Ma and charac-teristic of positive εNd(t ) values. Geochemical features and trace elements simulation indicate that the TTD series was probably originated from differently partial melting of tholeiitic rocks from the Erlangping group. Thermodynamic analysis on the residue phases of the partial melting pro- cesses suggests that the TTD series may represent a dynamic process of temperature-increasing and pressure-decreasing, indicating an extension and thinning process of a thickened crust. | TIAN Wei WEI Chunjing | 2005 | Science China Earth Sciences2005，48，11： | 4 |
| 14 | Explicit formula of holomorphic automorphism group on complex homogeneous bounded domains显示文摘We known that the maximal connected holomorphic automorphism group Aut (D)(0) is a semi-direct product of the triangle group T(D) and the maximal connected isotropic subgroup Iso (D)(0) of a fixed point in the complex homogeneous bounded domain D and any complex homogeneous bounded domain is holomorphic isomorphic to a normal Siegel domain D(VN,F).In this paper, we give the explicit formula of any holomorphic automorphism in T(D(VN,F)) and Iso (D(VN, F))(0), where G(0) is the unit connected component of the Lie group G. | XU Yichao,CHEN Minru & MA Songya Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China College of Mathematics and Information Sciences, Henan University, Kaifeng 475001, China | 2006 | Science China Mathematics2006，49，10： | 4 |
| 15 | Very low-grade metamorphism of the Meso-Neoproterozoic and the Lower Paleozoic along the profile from Huangtudian to Xianxi in the central-northern part of Hunan Province,China显示文摘The Lengjiaxi and Banxi groups of the Meso-Neoproterozoic and the Lower Paleozoic along the profile at Huangtudian-Xianxi of the central-northern Hunan Province, China underwent very low-grade metamorphism. Illite crystallinity (IC) data of the <2 mm fractions range from 0.18—0.21癉2q for the Lengjiaxi Group to 0.19—0.23癉2q for the Banxi Group to 0.20—0.29癉2q for the Sinian to the Lower Paleozoic (K黚ler index, corrected with Kisch IC set, 1991). This indicates that the metamorphic grade of the Lengjiaxi Group is in the epizone, the Banxi Group in the epizone-high anchizone, and the Sinian to the Lower Paleozoic mostly in the high anchizone along the profile investigated. The peak metamorphic temperature evaluated is roughly 340—240℃. This result does not agree with the greenschist or subgreenschist facies of the Lengjiaxi and Banxi groups and neither with the lower-greenschist facies or diagenitic zone of the Sinian to the Lower Paleozoic, of which most previous researchers thought. The illites (K-mica) b0 values range from 0.8989—0.9050 nm for the Lengjiaxi Group to 0.8984—0.9037 nm for the Banxi Group to the Lower Paleozoic. Based on the cumulative frequency curves of illite (K-mica) b0, the peak metamorphic pressure of the Banxi Group to the Lower Paleozoic along the profile was derived in a low-intermediate pressure type. Illites occur as 2M1 polytype in the Lengjiaxi and Banxi groups and as 2M1+1M types in some samples of the Lower Paleozoic. This indicates that the transformation of illite polytype from 1M to 2M1 was fulfilled within the high anchizone. | 王河锦 周健 徐庆生 刘楚雄 朱明新 | 2003 | Science China Earth Sciences2003，46，7： | 3 |
| 16 | Function spaces on local fields显示文摘We study the function spaces on local fields in this paper, such as Triebel Btype and F-type spaces, Holder type spaces, Sobolev type spaces, and so on, moreover,study the relationship between the p-type derivatives and the Holder type spaces. Our obtained results show that there exists quite difference between the functions defined on Euclidean spaces and local fields, respectively. Furthermore, many properties of functions defined on local fields motivate the new idea of solving some important topics on fractal analysis. | SU Weiyi XU Qiang | 2006 | Science China Mathematics2006，49，1： | 3 |
| 17 | On automorphism groups of some finite groups显示文摘We show that if n>1 is odd and has no divisor p4 for any prime p, then there is no finite group G such that |Aut(G)| = n. | 钱国华 | 2003 | Science China Mathematics2003，46，4： | 3 |
| 18 | The extension of the first main theorem for π-blocks显示文摘Let π be a set of primes and G a π-separable group. Isaacs defines the Bπ characters, which can be viewed as the 'π-modular' characters in G, such that the Bp′ characters form a set of canonical lifts for the p-modular characters. By using Isaacs' work, Slattery has developed some Brauer's ideals of p-blocks to the π-blocks of a finite π-separable group, generalizing Brauer's three main theorems to the π-blocks. In this paper, depending on Isaacs' and Slattery's work, we will extend the first main theorem for π-blocks. | HAI Jinke Department of Mathematics, Qingdao University, Qingdao 266071, China College of mathematics ,Shandong University, Jinan 250100, China | 2006 | Science China Mathematics2006，49，5： | 3 |
| 19 | New results on non-existence of generalized bent functions (Ⅱ)显示文摘Several new results on non-existence of generalized bent functions are presented by using the class group of related imaginary abelian number fields. | 刘凤梅 马智 冯克勤 | 2002 | Science China Mathematics2002，45，6： | 2 |
| 20 | Pedigree and Germplasm Base of Inbreds of the Lancaster Heterotic Group of Maize in China显示文摘Lancaster Surecrop (LSC) germplasm in inbreds of the Lancaster heterotic group in China was mainly provided by the two inbreds Mo17 and Oh43. Furthermore, the source of LSC germplasm was severely restricted in two inbreds, C103 and Oh40B. The contents of LSC germplasm are 50% or less in inbreds of the group, with the existence of more than 20 non-LSC germplasms that results in the abundant genetic diversity in the group. Most inbreds of Mo17 subgroup contain 25 % - 50 % LSC, 12.5 % - 25 % Reid Yellow Dent (RYD)and 12.5% - 25% Iowa Goldmine germplasms in the ratio of 2:1:1, and most inbreds of Zi330 subgroup contain 12.5%-25% LSC, 6.25%- 12.5% RYD, 6.25%- 12.5% Minnesota # 13 and 25%- 50% Creole germplasms in the ratio of 2:1:1: 4. All the facts indicated that the germplasm base of the Lancaster heterotic group has stupendously changed and evolved away from actual LSC germplasm. | ZHENG Da-hao, LI Yan-ru, JIN Feng-xue and JIANG Ji-jian(Department of Agronomy, Agricultural College, Yanbian University, Jilin 133400, P.R.China) | 2002 | Agricultural Sciences in China2002，1，6： | 2 |
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