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Chinese science Bulletin 2007年第7期52卷 936-941页

作者： SHI RenDeng1,2 1 school of Earth and Space sciences, university of science and technology of china, hefei 230026, china 2 Institute of Geology, Chinese Academy of Geological sciences, Beijing 100037, china (email: shird@***) school of Earth and Space sciences University of Science and Technology of China Hefei China Institute of Geology Chinese Academy of Geological Sciences Beijing China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The SHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 SSZ型蛇绿岩 SHRIMP 测年

Electron surfing acceleration in a current sheet of flares

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science china(Physics,Mechanics & Astronomy) 2009年第11期52卷 1810-1812页

作者： WANG DeYu1 & LU QuanMing2 1 Purple Mountain Observatory, Nanjing 210008, china 2 school of Earth and Space sciences, university of science and technology of china, hefei 230026, china Purple Mountain Observatory Nanjing China school of Earth and Space sciences University of Science and Technology of China Hefei China

A model of electron acceleration in a current sheet of flares is studied by the analytical approximation solution and the test particle simulation. The electron can be trapped in a potential of propagating electrostatic wave. The trapped electron moving with the phase velocity v p of wave may be effectively accelerated by ev p/c × B z force along the outflow direction in the current sheet, if a criterion condition K > 0 for electron surfing acceleration is satisfied. The electron will be accelerated continuously until the electron de-trap from the wave potential at the turning point S.

关键词： electron acceleration electrostatic wave current sheet

Mantle xenoliths from Late Cretaceous basalt in eastern Shandong Province: New constraint on the timing of lithospheric thinning in eastern china

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Chinese science Bulletin 2003年第19期48卷 2139-2144页

作者： YAN Jun, CHEN Jiangfeng, XIE Zhi & ZHOU Taixi school of Earth and Space sciences, university of science and technology of china, hefei 230026, china school of Earth and Space sciences University of Science and Technology of China Hefei China

The age of the alkali basalt from Daxizhuang in Jiaozhou, eastern Shandong, was determined to be 73.5±0.3 Ma by 40Ar-39Ar technique. The basalt gave high eNd(t) values of +7.5 and +7.6, suggesting that the primitive magma was derived from depleted asthenospheric mantle with a formation depth of about 65—95 km. Spinel-lherzolite xenoliths have been discovered in the basalt. The Fo values of olivine from the xenoliths range from 88 to 89. The estimated equilibrium P-T conditions of spinel-lherzolite xenoliths are about 2.0 GPa and 1010—1140℃, suggesting an equilibrium depth of about 65 km. Geochemical characteristics of the Late Mesozoic (125—115 Ma) mantle-derived rocks in Shandong Province suggest an enriched lithospheric mantle along the southern margin of the North china block. However, geochemical characteristics of the Late Cretaceous basalts in Daxizhuang and the equilibrium P-T condition estimated from the xenoliths suggest that the lithosphere at 73 Ma ago was as thick as that of the Cenozoic in the region. Additionally, the xenoliths are rich in basaltic-component, suggesting a derivation from a newly-formed lithosphere. Therefor, lithospheric thinning took place at a time interval between about 120 and 73 Ma along the southern margin of the North china block.

关键词：覆盖捕虏岩白垩纪玄武岩山东东部地区岩石圈稀释化 ^40Ar-^39Ar技术

A NOTE ON THE CONSISTENCY OF LS ESTIMATES IN LINEAR MODELS

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Chinese Annals of Mathematics,Series B 2001年第4期22卷 471-474页

作者： CHEN XIRU The graduate school at Beijing, university of science and technology of china, Beijing 100039, china. The graduate school at Beijing University of Science and Technology of China Beijing 100039 China

It is well known that when the random errors are iid. with finite variance, the week and the strong consiStency of LS estimate of multiple regression coefficients are equivalent. This note, by constructing a counter-example, shows that this equivalence no longer holds true in case that the random errors possess only the r-th moment with 1≤5 T ＜ 2.

关键词： Linear regression model Consistency LS estimate

cDNA cloning,sequence analysis,and recombinant expression of akitonin beta,a C-type lectin-like protein from Agkistrodon acutus

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Acta Pharmacologica Sinica 2004年第3期25卷 118-123页

作者： Xiang-dong ZHA1,2,Jing LIU1,Kang-sen XU3 1 school of Life science,university of science and technology,hefei 230026 school of Life science,Anhui university,2 hefei 230039 National Institute for Control of Pharmaceuticals and Biological Products,Beijing 100050,china 3 school of Life science University of Science and Technology Hefei 230026 National Institute for Control of Pharmaceuticals and Biological Products 北京 100050

AIM: To clone the cDNA of a new member of snake venom C-type lectin-like proteins, to study its structure- function relationships and to achieve its recombinant production. METHODS: PCR primers were designed based on the homology and cDNA was amplified by RT-PCR using total RNA from snake venom gland as the template. The PCR products were cloned into the plasmid pGEM-T and sequenced. The deduced protein sequence was analyzed with some bioinformatic programs. A recombinant expression plasmid was constructed using pBAD- TOPO as vector and transformed into *** TOP10 competent cells. RESULTS: A novel cDNA sequence encod- ing akitonin β was found and accepted by GenBank (accession number AF387100). Akitonin β consists of a typical carbohydrate recognition domain (CRD) of C-type lectins, and it is homologous with other snake venom C-type lectin-like proteins. It was predicted to be a platelet antagonist. Upon induction with arabinose rAkitonin β express- ing in E coli was achieved at a high level (superior to 150 mg/L). The recombinant fusion protein exhibited inhibitory activities on rat platelet aggregation in vitro. CONCLUSION: A new member of snake venom C-type lectin-like proteins was discovered and characterized, and an efficient recombinant expression system was estab- lished for its production.

关键词： snake venoms cDNA akitonin C-type lectin-like proteins recombinant proteins structure- activity relationship

Magnetic Energy of Force-Free Fields with Detached Field Lines

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 555-562页

作者： Guo-Qiang Li and You-Qiu Huschool of Earth and Space sciences, university of science and technology of china, hefei 230026 school of Earth and Space sciences University of Science and Technology of China Hefei 230026

Using an axisymmetrical ideal MHD model in spherical coordinates, we present a numerical study of magnetic configurations characterized by a levitating flux rope embedded in a bipolar background field whose normal field at the solar surface is the same or very close to that of a central dipole. The characteristic plasma β (the ratio between gas pressure and magnetic pressure) is taken to be so small (β = 10-4) that the magnetic field is close to being force-free. The system as a whole is then let evolve quasi-statically with a slow increase of either the annular magnetic flux or the axial magnetic flux of the rope, and the total magnetic energy of the system grows accordingly. It is found that there exists an energy threshold: the flux rope sticks to the solar surface in equilibrium if the magnetic energy of the system is below the threshold, whereas it loses equilibrium if the threshold is exceeded. The energy threshold is found to be larger than that of the corresponding fully-open magnetic field by a factor of nearly 1.08 irrespective as to whether the background field is completely closed or partly open, or whether the magnetic energy is enhanced by an increase of annular or axial flux of the rope. This gives an example showing that a force-free magnetic field may have an energy larger than the corresponding open field energy if part of the field lines is allowed to be detached from the solar surface. The implication of such a conclusion in coronal mass ejections is briefly discussed and some comments are made on the maximum energy of force-free magnetic fields.

关键词： Sun: magnetic fields - Sun: coronal mass ejections (CMEs) -methods: numerical

Asymptotic normality and strong consistency of maximum quasi-likelihood estimates in generalized linear models

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science china Mathematics 2006年第2期49卷 145-157页

作者： YIN Changming, ZHAO Lincheng & WEI Chengdong school of Mathematics and Information science, Guangxi university, Manning 530004, china Department of Statistics and Finance, university of science and technology of china, hefei 230026, china Department of Mathematics, Guangxi Teacher College, Manning 530001, china school of Mathematics and Information science Guangxi University Nanning China Department of Statistics and Finance University of Science and Technology of China Hefei China Department of Mathematics Guangxi Teacher College Nanning China

In a generalized linear model with q x 1 responses, the bounded and fixed (or adaptive) p × q regressors Zi and the general link function, under the most general assumption on the minimum eigenvalue of ZiZ'i,the moment condition on responses as weak as possible and the other mild regular conditions, we prove that the maximum quasi-likelihood estimates for the regression parameter vector are asymptotically normal and strongly consistent.

关键词： generalized linear models quasi-likelihood estimates asymptotic normality strong consistency.

Alterations in circadian rhythms of melaton in and cortisol in patients with bronchial asthma

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Acta Pharmacologica Sinica 2004年第5期25卷 109-114页

作者： Guang-he FEI2,3, Rong-yu LIU3,4, Zhi-hong ZHANG3, Jiang-ning ZHOU2,32school of Life science, university of science and technology of china, hefei 230026, china 3Pulmonary Department, First Affiliated Hospital, Anhui Medical university, hefei 230022, china school of Life science University of Science and Technology of China Hefei 230026 Pulmonary Department First Affiliated Hospital Anhui Medical University Hefei 230022 Pulmonary Department First Affiliated Hospital Anhui Medical University Hefei 230026

AIM: To investigate the possible relationships between alterations in circadian rhythm of melatonin, cortisol andbronchial asthma. METHODS: Salivary melatonin and cortisol were measured simultaneously by radioimmunoas-say in 10 mild intermittent or persistent patients, 11 moderate-to-severe persistent asthma patients, and 15 controlsubjects. Twelve salivary samples were collected in a series during a 24-h period in each subject. RESULTS: Theresults showed overall lower levels of salivary melatonin in asthma patients compared with control subject(P24-h mean level of salivary cortisol was greatly lower and the acrophase was markedly delayedin patients with mild intermittent or persistent asthma (P<0.01) and moderate-to-severe persistent asthma (P<0.05, P<0.01) compared with control subject. CONCLUSION: Disordered circadian rhythms of salivary melato-nin and cortisol were found in asthma patients, which may be involved in the pathogenesis of bronchial asthma.

关键词： melatonin asthma circadian rhythm glucocorticoids human saliva

Ice-volcanism due to tidal stress on Europa

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Chinese science Bulletin 2003年第13期48卷 1390-1392页

作者： LI Li & CHEN Chuxin school of Earth and Space sciences, university of science andtechnology of china, hefei 230026, china school of Earth and Space sciences University of Science and Technology of China Hefei 230026 China

Tectonism would be driven by tidal heat onEuropa, and there may be ice-volcano on the surface ofactive Europa. We assume that ice-volcano would spurt out due to tidal stress, and calculate the velocity and height of t... 详细信息

关键词：潮汐应力木卫二构造作用冰山火山

Decoupling of surface and subsurface sutures in the Dabie orogen and a continent-collisional lithospheric-wedging model: Sr-Nd-Pb isotopic evidences of Mesozoic igneous rocks in eastern china

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Chinese science Bulletin 2003年第8期48卷 831-838页

作者： LI Shuguang & YANG Wei school of Earth and Space sciences, university of science and Tech-nology of china, hefei 230026, china school of Earth and Space sciences University of Science and Technology of China Hefei 230026 China

There are significant differences of Nd and Pbisotopic compositions between Mesozoic mafic igneous rocks from the North china Block (NCB) and the South chinaBlock (SCB). Mesozoic mantle-derived igneous rocks fromthe North china Block have very low e Nd values (-15 to -21), and 206Pb/204Pb ratios ( -10 and 206Pb/204Pb > 18.3. The verylow e Nd values (-16 to -20) and 206Pb/204Pb ratios (< 17.3) of the early Cretaceous mafic-ultramafic intrusions developedin the north part of the Dabie orogen (NDZ) suggest that the deep lithosphere underneath the NDZ belongs to the NCBbut not the SCB. Therefore, although the surface suture be-tween the NCB and SCB is located on the north side of theNDZ, the subsurface suture between the NCB and SCBshould be located to the south side of the NDZ. This is con-sistent with the previous suggestion that the subsurface su-ture in the Sulu terrane east of the Tanlu fault was the south displacement, but contradictory to northward continentalsubduction of the SCB. A continent-collisional lithospheric-wedging model can interpret the decoupling of the surface and subsurface sutures in the Dabie-Sulu orogen. After slabbreak-off, the continuing convergence of two continental blocks must increase the compression force acting on the suture zone, which might induce the lithosphere splitting of SCB. Thus, the lower crust and lithospheric mantle on thesouth margin of the NCB can wedge into the north margin of the lithosphere of the SCB along the Dabie-Sulu collisionzone. This process caused the overthrust of the mid-upper continental crust with exhumed ultrahigh pressure meta-morphic (UHPM) rocks and underthrust of the deep litho-sphere of the SCB. It could be an important mechanism re-sponsible for the second rapid cooling and uplifting of theUHPM rocks and lithospheric delamination as well as thecorresponding magmatism in Jurassic in the Dabie *** southward movement of subsurface suture

关键词：大别造山带同位素中生代火成岩中国