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Qian J.F.,Zhejiang Institute of Geology and Mineral Resources
Advanced Materials Research | Year: 2014

The Structural and deformational features of fold-thrust belt in the north margin of Kashi, southern Tian Shan were disclosed based on various data such as two dimensional seismic profile and field geologic survey. The results show that the fold-thrust belt can be divided into several rows of anticlines, including Kalaboketuoer-Wenguer, Tuopa-Kangxiweier, Atushi and Kashi on plane, and the development of Atushi anticlines and its north side was controlled by the activity of the thrust system originated along the middle Cambrian Awatage Group from north to south. The fold-thrust belt can be divided into two different spatial levels: the shallow tectonic is a large scale imbricate thrust system, the detachment surface is uplifted from Cambrian system to Neogene system; the deep structure is a buried duplex structure system, the fault in floor and fault in roof are located at gypsic horizon in Cambrian and Neogene system respectively. Based on structural deformation analyzing and balanced section technology, the distribution of each anticlinal belt and the structure style of the low and deep thrust systems are confirmed. In this area the distance is shortened by 32.64~49.1km from north to south since Pliocene with the scalage of 40.5%~50.51%, and its average crustal shortening rate is 9.11~13.71mm/a. © (2014) Trans Tech Publications, Switzerland.

Chen X.-G.,Zhejiang University | Lv S.-S.,Zhejiang Institute of Geology and Mineral Resources | Zhang P.-P.,State Oceanic Administration | Zhang L.,Zhejiang University | Ye Y.,Zhejiang University
Journal of Thermal Analysis and Calorimetry | Year: 2011

In this study, we ashed rice hull in air and nitrogen, respectively, and systematically investigated the effects of ashing temperature and atmosphere on the structures, morphologies, and pore characteristics of rice hull ash (RHA). All RHA samples are amorphous materials with porous structures. IR spectra revealed that RHA that ashed in air (WRHA) exhibit more polar groups on the surface than that of ashed in nitrogen (BRHA). The silica and carbon contents, BET surface area, and pore volume of BRHA increase with ashing temperature. When ashed in air, however, the silica content of WRHA increases and carbon content decreases with temperature. The BET surface area and pore volume of WRHA increase with temperature firstly and decline subsequently due to the closure of pores. Compared with WRHA, BRHA shows higher surface areas, micropore volumes, carbon contents, and lower mesopore fractions and silica contents. This study provides essential information for choosing a suitable thermal treatment of rice hull for a given adsorbate. © 2010 Akadémiai Kiadó, Budapest, Hungary.

Xue H.,Chinese Academy of Geological Sciences | Ma F.,Peking University | Song Y.,Zhejiang Institute of Geology and Mineral Resources
Acta Petrologica Sinica | Year: 2011

The Suizhou-Zaoyang area (northern margin of the Yangtze craton), where is the least affected area of the whole Qinling-Tongbaishan-Dabieshan-Sulu orogen and their foreland by the deep subduction of the Yangtze Craton beneath to the North China Craton and HP-UHP metamorphism during Triassic, relative well preserved Precambrian basement of the northern Yangtze Craton. These low-rank metamorphosed Precambrian rocks not only provide an ideal opportunity to study the palaeo-tectonic setting of the northern Yangtze Craton and nature of the lithosphere, but also are rare-references for resuming protolithes of the metamorphic complex in the orogen and examining the element mobility during HP-UHP metamorphism. The Precambrian rocks exposed here include Neoproterozoic volcanic-sedimentary rock series (Suizhou Group) and voluminous Neoproterozoic ultramafic-mafic sill swarm. The Suizhou Group is composed of meta-acidic volcanic rocks, meta-basic volcanic rocks, and meta-sedimentary rocks. The ultramafic-mafic sill swarm is composed predominantly of two-pyroxene troctolites, with minor gabbronorites and pyroxenites. In this work, we used zircon SHRIMP U-Pb technique accurately dating the rhyodacitic tuff and meta-trachyandesite of the Suizhou Group, as well as two-pyroxene troctolitic sill swarm, yielding an emplacement ages of 763 ±7Ma, 741 ±7Ma and 632 ±6Ma, respectively. The two former ages are similar to the emplacement ages of protolithes of the HP-UHP metamorphic rocks outcropped in the orogen, but it is still not sure whether there are any emplacement ages of protolith of the eclogite in the orogen are similar to the emplacement ages of the troctolitic sill swarm (632 ± 6Ma). Geochemically, the acidic volcanic rocks exhibit obvious depletion in Sr and high field strong elements (HFSEs) such as Nb and Ta, enrichment in strong incompatible elements such as Rb, Ba, Th, U and K as well as light rare earth elements (LREEs). This type of rocks also show characteristics of strong enrichment in LREE over the HREE ((La/Yb) N = 10. 44), and weak negative Eu anomalies (δEu = 0. 75), similar to the biotite plagiogneisses widely distributed in the Dabie-Sulu orogen and acidic end-member of bimodal volcanic rocks developed in rift setting. The meta-trachyandesite of the Suizhou Group show no fractionation between LREE and HREE, no negative HFSEs anomalies such as Nb and Ta, similar geochemically to most eclogites in the orogen. The troctolitic sill swarm is characterized by high A12O3 and MgO contents, low TiO 2 and alkaline contents, strong enrichment of LREE over HREE ((La/Yb) N = 5. 49), particular for strong positive Ba, Sr and Eu anomalies (δEu = 1. 22), indicating plagioclase crystallization/accumulation. No HFSEs such as Nb, Ta, U, Th, Zr and Hf anomalies for the troctolitic sill swarm show little contamination of crustal material during evolution of the magmas, and that the parent magma could be derived from partial melting of an enriched subcontinental lithospheric mantle.

Chen X.-G.,Zhejiang University | Cheng J.-P.,Zhejiang University | Lv S.-S.,Zhejiang Institute of Geology and Mineral Resources | Zhang P.-P.,State Oceanic Administration | And 2 more authors.
Composites Science and Technology | Year: 2012

Strong absorption, low density, and thin matching thickness are important parameters for electromagnetic (EM) wave absorbers. In this study, we prepared novel porous magnetic nanocomposites using corncob powders as template. The presence of corncob will significantly decrease the bulk density of samples from more than 4.0 to about 0.55gcm -3. The porous structures remarkably decreased the permittivity (ε) and permeability (μ) and enhanced the impendence matching between the absorber and air. The porous magnetic nanocomposites exhibit enhanced absorption for EM waves at thin matching thickness. The optimum thickness is only 1.0-1.4mm, with bandwidth of RL<-5dB of about 8GHz, covering the half X-band and the whole K u-band. The areal density of magnetic absorbers at this study is only about 0.7-1.0kgm -2 at thickness of 1.0-1.4mm, much lower than the reported values of other magnetic absorbers. Due to the strong absorption at low density and thin matching thickness, the porous magnetic nanocomposites prepared using corncob powders as template are promising light-weight EM wave absorbers. © 2012 Elsevier Ltd.

Zhu Z.,Zhejiang University | Wu H.,Xinxiang Medical University | Wu S.,Zhejiang Institute of Geology and Mineral Resources | Huang Z.,Zhejiang University | And 2 more authors.
Journal of Chromatography A | Year: 2013

A simple and sensitive method was developed for simultaneous determination of methotrexate (MTX) and folic acid (FA) by ion chromatography with electrochemical detection (IC-ECD). Quaternary amine functionalized multi-wall carbon nanotubes (q-MWNTs) modified glassy carbon electrode (GCE) was used as an amperometric sensor to determine MTX and FA. The electrochemical behaviors of MTX and FA at the q-MWNTs/GCE were studied by cyclic voltammetry (CV). Results indicated that this modified electrode exhibited electrocatalytic oxidation toward MTX and FA with high sensitivity, stability and long life. Good separation of MTX and FA was demonstrated by IC on an anion-exchange column with phosphate buffer solution (PBS) as eluent. Under the optimal conditions, the linear ranges were from 0.01 to 20. mg/L for both MTX and FA with correlation coefficients r≥. 0.9994. The obtained detection limits (LODs) for MTX and FA were 0.2 and 0.4 μg/L (S/. N=. 3), respectively. The method has been successfully applied to the determination of MTX and FA in plasma and urine of patients of rheumatoid arthritis. © 2013 Elsevier B.V.

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