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Indian Ocean-MORB-type isotopic signature of Yushigou ophiolite in North Qilian Mountains and its implications

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Science china Earth Sciences 2006年第6期49卷 561-572页

作者： HOU Qingye1,2, ZHAO Zhidan1,2, zhang Hongfei3, zhang Benren3 & CHEN Yuelong2 1. State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences, Beijing 100083, china 2. school of Earth Science and Mineral Resources, china university of geosciences, Beijing 100083, china 3. Faculty of Earth Sciences, china university of geosciences, wuhan 43.074, china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. school of Earth Science and Mineral Resources China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

In order to explore the disputed issue concerning the tectonic affinity ofthe ancient ocean mantle of North Qilian Mountains (NQM), geochemical and Sr, Nd, Pb isotopiccompositions of pillow basalts of the Yushigou Ophiolite (YSGO) suite from NQM have been analyzedsystematically. The pillow basalts exhibit tholeiitic characteristics, with flatchondrite-normalized REE patterns ((La/Yb)_N = 0.98—1.27). They display no Nb, Ta, Zr, Hf negativeanomalies, and show MORB features in 2Nb-Zr/4-Y and Ti/100-Zr-YX3 tectonic discrimination *** results indicate that the Yushigou ophiolite is most likely to be formed in a mid-ocean ridgeor mature back-arc basin. Their isotopic data show a relatively broad and enriched ^(87)Sr/^(86)Sr(0.70509 — 0.70700), restricted ^(143)Nd/^(144)Nd (0.512955-0.512978). Pb isotopes are in the rangeof ^(206)Pb/^(204)Pb (18.054-20.562), ^(207)Pb/^(204)Pb (15.537-15.743) and ^(208)Pb/^(204)Pb(38.068-38.530). These isotopic data imply that the basalts originated from the depleted mantle(DMM), with the involvement of enriched mantle components (mainly EMII). Geochemical comparisonsbetween the basalts in YSGO and the MORB-type basalts of ophiolite suites occurring in the knownancient Tethyan tectonic domain indicate that the ancient oceanic mantle represented by YSGO suiteforming in early Paleozoic in the North Qilian Moutains is very similar to the Tethyan mantle inboth trace elements and isotopic compositions. The North Qilian Mountains should be a part of theTethyan tectonic domain in early Paleozoic. This further implies that the Tethyan tectonic domaincan be deduced to early Paleozoic in the study area, which will be helpful to discussing thetectonic affinity and evolution of the North Qilian Mountains.

关键词： geochemistry, Indian Ocean-MORB-type isotopic signatures, Tethyan tectonic domain, Yushigou ophiolite, North Qilian Mountains.

SILYLATION OF CELLULOSE WITH TRICHLOROSILANE AND TRIETHOXYSILANE IN HOMOGENEOUS LiCl/N,N-DIMETHYLACETAMIDE SOLUTION

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Chinese Journal of Polymer Science 2000年第2期18卷 161-168页

作者： Hai-qing Liu Li-na zhang Department of Chemistry, wuhan university, wuhan 430072, china wuhan Univ Dept Chem Wuhan 430072 Peoples R China

Silyl celluloses (SiC) were prepared by reacting cellulose with chloropropyltrichlorosilane (CPTCSi) and chloropropyltriethoxysilane (CPTESi) in LiCl/N,N-dimethylacetamide (DMAc). The Si content in the silyl cellulose could be controlled by adjustment of the molar ratio of silane and cellulose. FT-IR spectra showed that cellulose was readily reacted with the above two silane reagents, and the reactivity of CPTCSi is higher than that of CPTESi. It was presumed that the reaction process belongs to graft-polymerization. The results of differential thermal analysis (DTA) indicated that the thermostability of the materials produced increased with the increase of Si content in the sample. The acid resistance of the samples SiC in 1 mol/L HCl aqueous solution was improved significantly. When Si content was ca. 20%, the silyl cellulose has excellent thermostability, hydrophobicity, low density and stability in 1 mol/L HCl aqueous solution, owing to crosslinking of cellulose chain with silane.

关键词： sily cellulose chloropropyltrichlorosilane chloropropyltriethoxysilane LiCl/DMAc thermostability crosslinking

SOLUTION PROPERTIES OF ANTITUMOR CARBOXYMETHYLATED DERIVATIVES OF α-(1→3)-D-GLUCAN FROM GANODERMA LUCIDUM

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Chinese Journal of Polymer Science 2001年第3期19卷 283-289页

作者： Li-na zhang Mei zhang Jing-hua Chen Fan-bo Zeng Department of Chemistry wuhan university, wuhan 430072, china Pharmacy College, Tongji Medical university, wuhan 430072, china wuhan Univ Dept Chem Wuhan 430072 Peoples R China Tongji Med Univ Coll Pharm Wuhan 430072 Peoples R China

Fractions of a water insoluble α-(1→3)-D-glucan (GL) extracted from Ganoderma lucidum were carboxy-methylated (CM) to obtain water-soluble carboxymethylated derivatives (CM-GL) having a degree of substitution (DS) of0.38～0.51. Weight-average molecular weight M_w and intrinsic viscosity [η] of the samples CM-GL were measured by gelpermeation chromatography combined with laser light scattering (GPC-LLS) and viscometry. The CM-GL exhibits a stifferchain in aqueous solution at 25℃ than the original glucan, The antitumor activities against Ehrlich ascites carcinoma (EAC,5×10~6) of the carboxymethylated derivatives from the α-glucan and curdlan, a β-glucan, are significantly higher than thoseof the original glucans. The effects of the relatively low molecular weight, expanded chains and better water-solubility of theCM-GL on the enhancement of antitumor activity could not be neglected. The chain stiffness decreased speedily withincrease of temperature from 40 to 60℃ or NaOH concentration from 0.1 to 0.4 in the solution, respectively, and the changeof the chain stiffness is reversible.

关键词： Solution properties Antitumor activity Carboxymethylated derivative α-D-glucan Ganoderma lucidum

Wave Equations about Displacement, Velocity, Stress and Strain in FGM with Constituents Varied Continuously and Smoothly

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Journal of wuhan university of Technology(Materials Science) 2008年第5期23卷 767-769页

作者：左红心 school of Sciences Wuhan University of Technology

The wave equations about displacement, velocity, stress and strain in functionally gradient material （FGM） with constituents varied continuously and smoothly were established. Four kinds of waves are of linear second-order partial differential equation of hyperbolic type and have the same characteristic curve at the plane of X,t. In general, the varying mode of stress is different from that of displacement and velocity at the front of wave. But in a special case that the product of density p and elastic modulus E of the material remains unchanged, the three wave equations have a similar expression and they have a similar varying mode in the front of wave.

关键词： FGM constituents varied wave equation comparison.

Tectonic-Hydrocarbon Accumulation Analysis of Laoyemiao Region in Nanpu Sag,Bohai Bay Basin

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地学前缘 2009年第S1期16卷 154-155页

作者： Cuimei zhang,Xiaofeng Liu,Jianye Ren Faculty of Earth Resources,china university of geosciences(wuhan),wuhan 43.074,china.

Nanpu sag lies in the northwest part of the Bohai bay *** structural zone is located in the northwest part of the sag,to the north bound by basin-bounding master fault-Xi’nanzhuang fault (XNZF).This paper aims to gai... 详细信息

关键词： tectonic-hydrocarbon accumulation analysis Laoyemiao region Nanpu sag

"Three-Component" Digital Prospecting Method: A New Approach for Mineral Resources Quantitative Prediction and Assessment

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Journal of Earth Science 2004年第3期 6-13页

作者： Zhao Pengda Chioa university of geosciences, wuhan 43.074, china Chen Jianping school of the Earth Sciences and Resources, china university of geosciences, Beijing 100083, china Chen Jianguo Institute of Mathematical Geology, china university of geosciences, wuhan 43.074, china zhang Shouting school of the Earth Sciences and Resources, china university of geosciences, Beijing 100083, china Chen Yongqing china Geological Survey, Beijing 100073, china

Three-component" method consists of three close-connected aspects: geological anomaly, diversity of mineralization and mineral deposit spectrum. All these three concepts are not new separately, but it is a new approach to combine these three aspects in one single concept for quantitative mineral resources prediction and assessment and it is also the first time to conduct a more detailed study in each aspect. Investigation and clarification of geological anomalies, diversity of mineralization and spectrum of mineral deposits are realized by digitization and quantification of ore forming controlling factors, ore-existing symbols or marks, characteristics of mineralization and regulation of ore-genesis and laws of distribution. These procedures lead to construction of a "digital model" for mineral resources prediction and assessment.

关键词： three-component" method geological anomaly diversity of mineralization spectrum of mineral deposits.

Research and Implementation of Unsupervised Clustering-Based Intrusion Detection

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wuhan university Journal of Natural Sciences 2003年第3A期8卷 803-807页

作者： Luo Min, zhang Huan\|guo, Wang Li\|na school of Computer, wuhan university, wuhan 430072, Hubei, china wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

An unsupervised clustering\|based intrusion detection algorithm is discussed in this paper. The basic idea of the algorithm is to produce the cluster by comparing the distances of unlabeled training data sets. With the classified data instances, anomaly data clusters can be easily identified by normal cluster ratio and the identified cluster can be used in real data detection. The benefit of the algorithm is that it doesn't need labeled training data sets. The experiment concludes that this approach can detect unknown intrusions efficiently in the real network connections via using the data sets of KDD99.

关键词： intrusion detection data mining unsupervised clustering unlabeled data

A High Precision Forecasting Model and Its Constructing Method for Vein Type Gold Deposits

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Journal of china university of geosciences 2001年第2期12卷 100-107页

作者： zhang Jun Faculty of Earth Resources, china university of geosciences, wuhan 43.074 Faculty of Earth Resources China University of Geosciences

A high precision forecasting and prospecting model incorporating the “field theory field structure analysis field simulation”, a temporal and spatial structural framework reflecting local extremely fine structures, is established to make an effective extraction and an integrated analysis of multivariate forecasting information. This model can best show not only the coupling between metallogenic anomalous structure, mineralized structure and information structure, but also the extraction, optimization, matching and summarization of key forecasting information. The technological keys to this model are the fine structural analysis of geological and geophysical and geochemical anomalous fields and metallogenic fields, and the establishment of occurrence patterns for the spatial location of orebodies.

关键词： high precision forecasting model anomalous structure mineralized structure orebody location.

Secure, dependable and publicly verifiable distributed data storage in unattended wireless sensor networks

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Science china(Information Sciences) 2010年第5期53卷 964-979页

作者： REN Wei 1 , REN Yi 2 & zhang Hui 3 1 school of Computer Science, china university of geosciences (wuhan), wuhan 43.074, china 2 Department of Information and Communication Technology, university of Agder (UiA), Norway 3 Department of Electronics, Politecnico di Torino (POLITO), Italy 1. school of Computer Science China University of Geosciences (Wuhan) Wuhan 430074 China2. Department of Information and Communication Technology University of Agder (UiA) Kristiansand Norway3. Department of Electronics Politecnico di Torino (POLITO) Torino Italy

In unattended wireless sensor networks (UWSNs), sensed data are stored locally or at designated nodes and further accessed by authorized collectors on demand. This paradigm is motivated by certain scenarios where historical or digest data (e.g., average temperature in a day), instead of real-time data, are of interest. The data are not instantly forwarded to a central sink upon sensing, thereby saving communication energy for transmission. Such a paradigm can also improve data survivability by making use of distributed data storage in cheap flash memory on nodes. However, the security and dependability of such data storage are critical for the future data accessibility in UWSNs. To address this issue, we propose a secure and dependable distributed storage scheme for UWSNs. Our scheme takes advantages of both secret sharing and Reed-Solomon code, which can achieve computational security and maintain low communication overhead in terms of shortened data dispersing size. We also propose a general coding method to publicly verify data integrity in a distributed manner, with low communication and storage overhead, and without the need of holding original data. The extensive analysis justifies that our scheme can provide secure, dependable and publicly verifiable distributed data storage in UWSNs even in the presence of node compromise and Byzantine failure.

关键词： secure storage dependability data integrity wireless sensor networks wireless network security