检索结果-南通市图书馆

Mineralogy and crystal structure determination of Mg-fillowite

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1., SHI Nicheng 1.& YE Danian 2.1.{1. university of Geosciences, Beijing {2.,{1. 2. Institute of geology, Chinese Academy of Sciences, Beijing 1.002.,{1. 1. china {1. of Geosciences 100083 Beijing China 2. Institute of {1. Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-3, unit cell a=1.51.3(3) nm, c=4.31.1.2. nm, V=8.5736 nm3, Z = 1.. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, china: Implication for ore genesis

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1.2.& PAN Guitang2.1. Geoscience College, Chengdu university of Technology, Chengdu 61.059, china 2. Chengdu Institute of {2. and Mineral Resources, Chengdu 61.082. china 1. Geoscience College Chengdu University of Technology Chengdu 610059 China 2. Chengdu Institute of {1. and Mineral Resources Chengdu 610082 China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, china. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in china. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

复方碘口腔喷雾原位膜的制备及促口腔溃疡修复评价

在线全文

学校读者我要写书评

暂无评论

中国药科大学学报 2024年

作者：张小军黄山芩郭潇涵季梦菲沈雁陈大全许颖 1.江苏大学药学院 2.中国药科大学药学院 3.烟台大学药学院江苏大学药学院中国药科大学药学院烟台大学药学院

采用原位凝胶技术，制备了新型复方碘口腔喷雾原位膜，用于发挥缓释作用，并促进口腔溃疡创面修复。首先以喷雾状态和成膜时间为指标，对喷雾药液的处方和工艺进行优化。以成膜时间和药膜黏附性为评价指标对药液混合比例进行考察。并对... 详细信息

采用原位凝胶技术，制备了新型复方碘口腔喷雾原位膜，用于发挥缓释作用，并促进口腔溃疡创面修复。首先以喷雾状态和成膜时间为指标，对喷雾药液的处方和工艺进行优化。以成膜时间和药膜黏附性为评价指标对药液混合比例进行考察。并对最优处方制备的复方碘口腔喷雾药液的药物含量、稳定性、pH、喷雾效果，及原位膜的成膜时间、溶解性、吸湿性、保湿性、体外释放等理化性质进行考察；此外，通过细胞实验考察了成膜材料的生物相容性及复方碘口腔喷雾原位膜的促迁移效果；采用兔口腔溃疡模型，对复方碘口腔喷雾在体成膜效果及促修复效果进行评价。实验结果显示，最优处方制备的药液A和药液B的pH分别为6.2. ± 0.02. 6.42.± 0.03，符合正常口腔黏膜pH范围；稳定性好，具有良好的喷雾状态；药液B中碘含量为（1.96 ± 0.01.mg/mL；原位膜体外成膜时间为（1.8.3 ± 3.6）s，口腔内成膜时间为（1.3.3 ± 4.6）s；2. h溶解率为（87.31.± 1.74）%，吸湿率为（1.0}.1. ± 7.1.）%，保湿率为（2..85 ± 2.50）%；复方碘口腔喷雾原位膜中碘含量为（47.42.± 0.39）mg/g；具有良好的柔韧性和黏附性，并具有一定的缓释效果。细胞实验中，原位膜表现出良好的促成纤维细胞迁移作用。兔口腔溃疡实验表明，复方碘口腔喷雾在体可快速成膜，并可显著促进口腔溃疡修复。本研究所开发的复方碘口腔喷雾原位膜，制备工艺稳定，并可有效促进口腔溃疡创面修复，为口腔黏膜制剂的研究和开发提供了新思路，并具有良好的转化前景。

关键词：口腔喷雾原位膜复方碘口腔溃疡缓释促修复

Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth Sciences 2005年第5期48卷 585-600页

作者： YANG Wencai 1., YANG Wuyang 1., JIN Zhenmin 2.& CHENG Zhenyan 1.1. Institute of {1., Chinese Academy of Geological Sciences, Beijing 1.0037, china 2. china university of Geosciences, Wuhan 430074, china 1. Chinese Academy of Geological Sciences Institute of Geology 100037 Beijing China 2.{1. university of Geosciences 430074 Wuhan China

Calibration of seismic reflectors appearing in the crust of the Chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 1. km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu china, calibration of reflectors, lithospheric fabrics.

Analysis on the long term discharge of a catchment

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2000年第3期12卷 279-285页

作者： HONG Lin 1. TAKASE Keiji 2. SATO Koichi 2.(1. Wuhan university of Hydraulic and Electric Engineering, Wuhan 430072. china 2. Ehime university, Japan) Wuhan university of Hydraulic and Electric Engineering Wuhan 430072 China Ehime university Japan

In this study, the characteristics of the long term discharge of a Terraced Paddy Field Catchment are studied. 2.Kind of Tank Models are proposed and used to simulate the discharge of the catchment. The characteristics of the model simulations of the discharge of the catchment are analyzed and compared with those of a forest catchment.

关键词： long term discharge model simulation terraced paddy field catchment

Paleoceanographic evolution recorded in the northern South china Sea since 4 Ma

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2005年第12期48卷 2166-2173页

作者： HUANG Baoqi1.2. JIAN Zhimin2.& WANG Pinxian2.1. School of Earth and Space Sciences, Peking university, Beijing 1.0871. china 2. Laboratory of Marine {2., Tongji university, Shanghai 2.0092. china 1. School of Earth and Space Sciences Peking University 100871 Beijing China 2. Laboratory of Marine {1. Tongji University 200092 Shanghai China

Upper water structure over the last 4 million years in the northern South china Sea (SCS) was reconstructed by sea surface temperature (SST) and primary productivity estimated by changes in the abundance of planktonic foraminifer, planktonic foraminifer transfer function, and the accumulation rate of benthic foraminifera. Results of SST and primary productivity show that SST gradually decreased since 4 Ma, but differential seasonal temperature and primary productivity increased in steps mainly at about 3.1. {1.7, {1.1. 1.6, 0.9 and 0.5 Ma. Comparison with tectonics and orbital variations indicates that phased rising of the Tibet since 3.6 Ma, closing of Panama and Indonesian seaways, and orbital changes were responsible for the changes of upper water structure in the SCS, respectively.

关键词： northern South china Sea, upper water structure, Late Pliocene, planktonic foraminifer, ODP 1.46.

Changes of infrared absorption wave number of aromatic-ring C=C bond of vitrinite and their significance

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第12期43卷 1048-1050页

作者： XIAO Jianxin 1.and CHEN Shanqing 2.1.{1. university of Geosciences, Beijing {2.,{1. 2. Yichang Institute of geology and Mineral Resources, Yichang 443003,{1. china {1. of Geosciences Beijing China Yichang Institute of geology and Mineral Resources Yichang China

The humilith series of lignite, longflame coal, gas coal, fat coal, coking coal, lean coal, meagre coal and anthracite are measured by FIR1.00 infrared spectrophotometer. The variation curve between the infrared absorption wave number of aromaticring C--C bond of vitrinite and its reflectance values are gained, which shows the shift of infrared absorption wave number of aromaticring C--C bond of humic coals towards lower wave number with the increase of coalification. It is believed that the coal rank of humilith series can be determined and more evolutional information about coal composition and structure can be obtained by the infrared spectroscopic method.

关键词： aromatic_nucleus C--C bond infrared absorption wave number vitrinite humic coal.

Automorphisms with order three of affine Lie algebras

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第21期43卷 1793-1798页

作者： JIN Quanqin 1.2.and HOU Zixin 2.1. Department of Mathematics, Hebei university, Baoding 071.02. china 2. Department of Mathematics, Nankai university, Tianjin 300071. china Department of Mathematics Hebei University Baoding China Department of Mathematics Nankai University Tianjin China

Some properties of automorphisms of affine Lie algebras are presented. Automorphisms with order three are classified up to conjugacy, and their fixed point sets are also computed. As a corollary, it is proved that two... 详细信息

关键词： affine Lie algebra automorphism of order three first (second) kind of automorphism.

Population-size-dependent branching processes in Markovian random environments

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第8期43卷 635-638页

作者： WANG Hanxing 1.and DAI Yonglong 2.1. Department of Mathematics, Shanghai {1., Shanghai 2.1.00, china 2. Department of Mathematics, Zhongshan {1., Guangzhou 51.2.5, china Department of Mathematics Shanghai University Shanghai China Department of Mathematics Zhongshan University Gunngzhou China

A branching model {Z n} n≥0is considered where the offspring distribution of the population’s evolution is not only dependent on the population size, but also controlled by a Markovian environmental process {ξ n} n≥0. For this model, asymptotic behaviour is studied such as limn→∞Z n and limn→∞Z n/m n in the case that the mean m k, θof the offspring distribution converges to m>1.as the population size k grows to ∞. In the case that {ξ n} n≥0is an irreducible positive recurrent Markov chain, certain extinction (i.e. P(Z n=0 for some n)=1. and noncertain extinction (i.e. P(Z n=0 for some n)1. are studied.

关键词： Markov chains in random environments stochastic population models branching processes.