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Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, china 2. Changchun {2. of Applied chemistry, Chinese Academy of Sciences, Changchun 13002., china 1. chemistry and Chemical Engineering College of Henan University Kaifeng 475001 China 2. Changchun institute of Applied chemistry Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Microwave Irradiation Treatment of Wood Flour and Its Application in PVC-Wood Flour Composites

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Journal of wuhan University of Technology(Materials Science) 2007年第1期22卷 148-152页

作者：胡圣飞陈文 institute of Materials Science and Engineering Wuhan University of Technology School of Chemical and Environmental Engineering Hubei University of Technology Wuhan 430068China

The technique of microwave irradiation induced free radical bulk- polyaddition reactions in porous wood flour was used to modify wood flour. The behaviors of the modified wood flour under microwave irradiation, such as thermal stability and moisture sorption properties, were studied. A kind of semiinterpenetrating polymer network wood four （Semi-IPN-WF） can be formed through polymerization of MMA in the porous wood flour by microwave irradiation, and the thermal decomposition temperature of the semi-IPN-WF is considerably increased. PVC/Semi-IPN-WF composites were prepared by melt mixing in double rolls, which exhibit improved rheological properties, lower water sorption properties and outstanding mechanical performances.

关键词： microwave irradiation wood flour poly(vinyl chloride) composites

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china Earth Sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of Geodesy and Earth’s Dynamics,institute of Geodesy and Geophysics,Chinese Academy of Sciences,wuhan 430077,{2. 2.Graduate University of Chinese Academy of Sciences,Beijing 100049,{2. 3 institute of Geophysics,Huazhong University of Science and Technology,wuhan 430074,{2. 1. State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Geophysics Huazhong University of Science and Technology Wuhan 430074 China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2.09,which is significantly higher than the global sea level rise rate of 3.3±0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

EXPERIMENTAL STUDIES ON FREQUENCY CHARACTERISTICS OF THE FLUCTUATING PRESSURE ACTING ON THE APRON OF STILLING BASINS WITH LOW FROUDE NUMBER

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Journal of Hydrodynamics 1992年第4期4卷 21-26页

作者： Ding Zhuo-yi Yangtze River Scientific Research institute,wuhan {2. 430010,P.R.china Yangtze River Scientific Research Inst Wuhan China

Using four types of stilling basin models,this paper studies frequency characteris- tics of the fluctuating pressure acting on the stilling basin apron when Froude number is not greater than *** testing results show that the frequency of fluctuating pressure,f_s in the ranges of 0. 4Hz≤f_s≤1.1Hz.0.2.z≤f_s≤2.5Hz and 0.4Hz≤f_s≤*** be used as the design frequency corresponding to three patterns of hydraulic *** reliability of f_s for three jump patterns is all nearly equal to 90%.

关键词： frequency characteristics fluctuating pressure stilling basin apron

The deformation pattern and fault rate in the Tianshan Mountains inferred from GPS observations

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Science china Earth Sciences 2008年第8期51卷 1064-1080页

作者： YANG ShaoMin1,2. LI Jie1,3 & WANG Qi2.1 1 Research Center of Space Science and Technology, china University of Geosciences, wuhan 430074, china 2.institute of Seismology, china Earthquake Administration, wuhan 430071, china 3 Earthquake Administration of Xinjiang Uygur Autonomous Region, Urumqi 830011, china 1. Research Center of Space Science and Technology China University of Geosciences Wuhan 430074 China 2. institute of Seismology China Earthquake Administration Wuhan 430071 China 3. Earthquake Administration of Xinjiang Uygur Autonomous Region Urumqi 830011 China

Based on GPS measurements conducted from 1992.to 2.06, we present the current crustal movement velocity field for approximately 400 sites in the Tianshan Mountains and their adjacent areas, and estimate slip rates on the major faults using a 2.D elastic dislocation model. Our studies show slip rates within the range of 1―4 mm/a on the NW-SE trending strike-slip faults (such as Talas-Fergana fault) in the Tianshan Mountains. We also found the slip rates on the approximately WE-SN trending gently-dipping detachment fault vary from 10―13 mm/a for the southwest Tianshan Mountains to 2.5 mm/a for the eastern Tianshan Mountains, and to 6―12.mm/a for the Kyrgrz Tianshan. The GPS velocity field reveals that the total convergence is not uniformly distributed across the Tianshan Mountains, with 80%―90% of the N-S shortening absorbed along the southern and northern edges, and relatively little deformation accommodated within the interior. This first-order feature of strain pattern is explained best by underthrusting of adjacent blocks beneath the Tianshan Mountains along a basal detachment fault. We found the occurrence of historical M7―8 earthquakes somewhere in the locked ramp that connects the creeping and locking segments of the detachment, thereby resulting in elastic strain concentration and accumulation around it. The elastic strain confined in the upper crustal layer above the detachment ultimately releases through infrequent great earthquakes in the Tianshan Mountains, resulting in considerable folding and faulting at their margins. The Tianshan Mountains propagated outward and rose progressively as a wedge-shaped block.

关键词： Tianshan Mountains GPS slip rates tectonic deformation

High-Accuracy Measurement of the Dispersion of Chirped Fiber Gratings

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Chinese Journal of Lasers 2000年第4期9卷 32-37页

作者： SHU Xuewen 1 SHI Wei 2.JIANG Shan 2.HUANG Dexiu 1 ( 1 Department of Optoelectronics, Huazhong University of Sciences and Technology, wuhan 430074, china 2.Solid Devices {2., wuhan Research {2. of Posts and Telecommunica 华中理工大学湖北武汉武汉邮电科学研究院湖北武汉

A high accuracy test system for the dispersion measurement of chirped fiber gratings has been developed. The principle is based on converting the difficult measurement of the phase delay of light into the simple measurement of microwave. In our novel configuration, a lightwave component analyzer is used for the measurement of the phase delay with high resolution and as frequency tunable RF source. The test system has a wavelength resolution of 1 pm and a time delay resolution of <1 ps. A linearly chirped fiber reflection grating and a Gaussian apodized Bragg transmission grating have been tested with high resolution. Influences of noise in the measurements are also discussed and some new ideas are presented.

关键词： chirped fiber grating Bragg grating dispersion measurement

Trace elements in volcanic rocks from Yangba Formation, Bikou Group, Qinling area, china——Implications for tectonics

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Chinese Science Bulletin 1999年第S2期44卷 44-46页

作者： DING Zhenju~(1,2. and LIU Congqiang~1 1. Open Laboratory of Ore Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. china University of Geosciences, wuhan 430074, china Open Laboratory of Ore Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China china University of Geosciences Wuhan 430074 China

YANGBA Formation of Bikou Group is located in south Qinling, a famous orogenic belt separating Chinesecontinent into two parts: North china plate and Yangzi plate. The Yangba Formation comprises the maficand felsic volcanic rocks formed in an ancient seafloor environment during the Proterozoic era. The suitesof mafic and felsic volcanic rocks are petrochemically divided into tholeiite and calc-alkaline dacite, respectively, showing characteristics of bimodal volcanic rock mainly by lithology and major element content, and a lack of typical intermediate rocks. These signatures indicate that the volcanic rocks of YangbaFormation were generated in rift tectonics setting. The tholeiites of Yangba Formation are similar in trace element content to mid-ridge basalt, displaying a slight depletion to enrichment in light rare earth elements (LREE’s) (La/Yb_n = 0.6-1.4), slightfractionation between LREE (La/Sm_n =0.55-1.14) and HREE (Gd/Lu_n = 1.09-1.50), and relative flat patterns in whole. The decoupling of Eu to its neighboring elements in two samples likely indicates an effect of fractional crystallization in magma evolution. The La-La/Sm, Ni-La, Ni-Th, Ni-Ta,and Ni-Hf diagrams all support a conclusion that the mafic rocks are generated by partial melting pro-

关键词： trace element volcanic rock tectonics setting Bikou Group.

Assessing a soft twin tunneling numerical model using field data

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Journal of Pharmaceutical Analysis 2009年第1期21卷 36-41页

作者： Ke-shuan Ma1,2.Lie-yun Ding11. School of Civil Engineering and Mechanics,hubei Key Laboratory of Control Structure, Huazhong University of Science & Technology, wuhan 430074,{2. 2. Department of Civil Engineering, Nanyang institute of Technology, Nanyang 473004,{2.. School of Civil Engineering and Mechanics Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology Wuhan 430074 China Department of Civil Engineering Nanyang Institute of Technology Nanyang 473004 China

Using a five-floor building affected by the Yangtze River highway tunnels in wuhan as the engineering background, we have constructed a free-field model and a coupled model to study the soil, lining, foundations and upper structure, and analyze the rules of movements of building foundation and ground induced by single tunnel and twin tunnel excavation with the Finite Element Analysis method. It is shown that for the coupled model, the longitudinal displacement of each foundation increases slowly when the tunnel face gets close to the foundation section and then increases fast when the tunnel face moves away from the foundation during the single and twin tunneling. For a single tunnel, the surface settlements are overestimated by the free-field and coupled tunnel. This might be crucial in urban areas. Regarding the maximum settlements and the width of the settlement trough, the difference between the free-field model and the coupled model is quite obvious. This comparison with the field measurement value reveals that the coupled model seems to be superior to the free-field model. These results are of instructive significance for design and excavation.

关键词： finite element analysis three-dimensional slurry shield tunneling building settlement

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2. XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, wuhan 430074, china 2. institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 454003, china 3. Department of Computer Science, South-Central University for Nationalities, wuhan 430074, china 4. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china University of Geosciences wuhan china institute of Resources & Environments Henan Polytechnic University Jiaozuo china Department of Computer Science South-Central University for Nationalities wuhan china Laboratory of Marine Geology Tongji University Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.43 (‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..38 (‰ V-PDB) to ?2..14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3 X 15%)) values from 0.015 to 0.144, TOC values from 0.02. to 0.2.%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.2. to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2. climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.