检索结果-南通市图书馆

^(40)Ar/^(39)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1. CHEN Wen2, 3 & YANG Nong1.1. institute of Geomechanics, Chinese {1. of Geological Sciences, Beijing 1.0081. china 2. institute of Geology, Chinese {1. of Geological Sciences, Beijing 1.0037, china 3. institute of Geology and Geophysics, Chinese {1. of Sciences, Beijing 1.0029, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Geology Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (1.-1. Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 350℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/39Ar dating, late Cenozoic.

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1.3, GUO Zhengtang2,1. HAO Qingzhen1. YIN Qiuzhen1. YUAN Baoyin1.& LIU Tungsheng1.1. institute of Geology and Geophysics, Chinese {1. of Sciences, Beijing 1.0029, china 2. institute of Earth Environment, Chinese {1. of Sciences, Xi’an 71.075, china 3. institute of Geomechanics, Chinese {1. of Geological Sciences, Beijing 1.0081. china institute of Geology and Geophysics Chinese Academy of Sciences Beijing China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Earth Environment Chinese Academy of Sciences Xi’an China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 253.1.m sequence varies from 6 to 1. μm and the > 63 μm fraction representsonly 5.3% in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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6.21.± 0.02和 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；24 h溶解率为（87.31.± 1.74）%，吸湿率为（1.4.1. ± 7.1.）%，保湿率为（26.85 ± 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

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. china University of Geosciences, Beijing 1.0083, china 2. institute of Geology, Chinese academy of Sciences, Beijing 1.0029, china china University of Geosciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2Ca(Mn4Mg2Fe)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 > 2σ ( 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 720 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.

A new evolutionary theory deduced mathematically from entropy amplification

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第1期45卷 91-96页

作者： CHEN Jiminginstitute of {1., Chinese academy of preventive medicine, Beijing 1.0052, china institute of {1. Chinese Academy of Preventive Medicine Beijing China

A new evolutionary theory which is able to 黱ite the present evolutionary debates is deduced mathematically from the principle of entropy amplification. it suggests that the extensive evolution is driven by the amplification of entropy, or microscopic diversity, and the biological evolution is driven by the amplification of biodiversity. Forming high hierarchies is the most important way for the amplification and brings out spontaneously three kinds of selection. This theory has some positive cultural meanings.

关键词： evolutionary theory mathematics entropy biodiversity selection cultural meanings.

Wind vector retrieval using dual polarization imagery of ASAR

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2006年第11期16卷 1183-1187页

作者： SONG Guiting~ 1.2 , HOU Yijun~1.* and QI Peng~1.1. institute of Oceanology, Chinese {1. of Sciences, Qingdao 266071. china 2. Graduate School, Chinese {1. of Sciences, Beijing 1.0039, china) institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China

A new algorithm for retrieving wind vector using dual polarization imagery of advanced synthetic aperture radar (ASAR) is developed and tested. Based on the combination of co-polarization and cross-polarization, this new algorithm effectively eliminates the 1.0° ambiguity which occurs when using single imagery of the ASAR to retrieve wind vector. This algorithm also solves the problem that the retrieval results will break down on very small spatial scales. The results retrieved from dual polarization imagery of ASAR show that the wind speed and direction are in agreement with the data from Quikscat and buoy measurements. The root mean square errors of wind direction and speed between the retrieved results and data from Quikscat are 2.21. and 0.53 m/s, respectively. Comparisons between the new method and the traditional method show that the new methods fit the buoy data and Quikscat data a little better than the traditional method in this image.

关键词： wind vector retrieval ASAR dual polarization.

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 Geology, Chinese {1. of Geological Sciences, Beijing 1.0037, china 2. china University of Geosciences, Wuhan 430074, china Chinese academy of Geological Sciences Institute of Geology Beijing China china University of Geosciences 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.

Geochemical simulation of the formation of brine and salt minerals based on Pitzer model in Caka Salt Lake

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2004年第8期47卷 720-726页

作者： LIU Xingqi1. CAI Keqin2 & YU Shengsong3 1. Nanjing institute of Geography and Limnology, Chinese {1. of Sciences, Nanjing 21.008, china 2. china University of Geosciences, Beijing 1.0083, china 3. institute of Salt Lakes, Chinese {1. of Sciences, Xining 81.008, china Nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing China china University of Geosciences Beijing China institute of Salt Lakes Chinese Academy of Sciences Xining China

The geochemical simulation of the formation of brine and salt minerals based on Pitzer model was made in Caka Salt Lake. The evolution of the mixed surface-water and the mineral sequences were calculated and compared with the hydrochemical compositions of the brine and the salt minerals of the deposit in Caka Salt Lake. The results show that the formation temperature of the lake is between 0°C and 5°C, which is well identical with other studies. The mixing of salt-karst water with the surface waters, neglected by the former researchers, is very important to the formation of the lake, indicating that the initial waters resulting in the formation of the lake are multi-source. It is the first time to use Pitzer model in china for making geochemical simulation of the formation and evolution of inland salt lake and satisfactory results have been achieved.

关键词： Pitzer model,Caka Salt Lake,geochemical simulation,salt-karst water.

The upper mantle structure of the Tibetan Plateau and its implication for the continent-continent collision

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2005年第8期48卷 1158-1164页

作者： WU Qingju1. ZENG Rongsheng1.& ZHAO Wenjin2 1. institute of Geophysics, {1. Earthquake Administration, Beijing 1.0081. {1. 2. institute of Geology, {1. academy of Geological Sciences, Beijing 1.0037, {1. institute of Geophysics China Earthquake Administration Beijing China institute of Geology China Academy of Geological Sciences Beijing China

The upper mantle structures of Himalayas-Tibet have been obtained from the mi-gration of receiver functions of the teleseismic events recorded by INDEPTH-III. The result of migration imaging shows a dipping interface subducting northward from the depth of 1.0 km to the 41.-km discontinuity underneath southern Tibet. It indicates that the lithospheric mantle of the Indian continent had been detached from the crust and deeply subducted to the upper mantle of Eurasia during the Indo-Eurasian collision. This kind of continent-continent collision process is fundamentally different from the oceanic collision.

关键词： Tibetan Plateau, receiver function, upper mantle structures, Indo-Eurasian collision, dipping interface.