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创新型人才素质组成结构研究
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作者 江世英 《襄樊职业技术学院学报》 2009年第2期33-35,共3页
创新型人才是推动社会进步、促进企业可持续发展的原动力。探究创新型人才素质组成对创新型人才的选拔、任用、激励和评价等均具有重要意义。创新型人才素质包括品格素质、价值观、脑力素质、能力素质、知识、态度、心理素质等因素。
关键词 创新型人才 素质组成 全面
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DRB在国际工程项目中的应用和特性研究
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作者 杨道富 《黄河水利职业技术学院学报》 2000年第4期24-26,共3页
介绍了DRB的起源与发展 ,叙述了DRB成员的组成过程 ,归纳了DRB人员的素质标准、基本职责、权利限制和不应有的利益冲突 ,研究了DRB体制的 8大特性 ,论述了DRB的工作内容、争议解决程序 。
关键词 DRB 起源与发展 素质组成 8大特性 应用研究
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Quantitative Effect of Soil Texture Composition on Retardation Factor of K^+ Transport 被引量:15
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作者 WANGYU ZHANGYIPING 《Pedosphere》 SCIE CAS CSCD 2001年第4期377-382,共6页
With six packed columns composed of < 1 μm and 5 μm~0.25 mm fractions from an Eum-Orthic An- throsol (Columns 1~6) and one column of the Eum-Orthic Anthrosol (Column 7), K~(+) transport experiments under the c... With six packed columns composed of < 1 μm and 5 μm~0.25 mm fractions from an Eum-Orthic An- throsol (Columns 1~6) and one column of the Eum-Orthic Anthrosol (Column 7), K~(+) transport experiments under the condition of saturated steady water flow were conducted to qualify the effects of soil texture com- position on the retardation factor (R) of K~(+) transport. The results showed that the retardation factor of K~ (+) transport in the tested soil columns greatly increased with increasing clay contents. In an attempt to use pedo-transfer function (PTF) approach in the solute transport study, a preliminary PTF was established through the six packed columns (Columns 1~6) with soil basic data including soil bulk density, volumet- ric water content and clay content to predict the retardation factor, and proved valid by the satisfactory prediction of R in Column 7. 展开更多
关键词 pedo-transfer function retardation factor soil basic properties soil solute transport
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An online method to determine chlorine stable isotope composition by continuous flow isotope ratio mass spectrometry (CF-IRMS) coupled with a Gasbench Ⅱ 被引量:3
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作者 刘运德 周爱国 +3 位作者 甘义群 刘存富 余婷婷 李小倩 《Journal of Central South University》 SCIE EI CAS 2013年第1期193-198,共6页
An online method using continuous flow isotope ratio mass spectrometry (CF-IRMS) interfaced with a Gasbench Ⅱ was presented to determine chlorine stable isotope composition. Silver chloride (AgCl) was quantitativ... An online method using continuous flow isotope ratio mass spectrometry (CF-IRMS) interfaced with a Gasbench Ⅱ was presented to determine chlorine stable isotope composition. Silver chloride (AgCl) was quantitatively derived from chloride by using silver nitrate (AgNO3), and then was reacted with iodomethane (CH3Ⅰ) to produce methyl chloride (CH3Cl). A GasBench Ⅱ equipped with a PoraPlot Q column was used to separate CH3Cl from any other gas species. Finally, chlorine stable isotope analysis was carried out on CH3Cl introduced to the IRMS in a helium stream via an active open split. The minimum amount of Cl used in this method is of the order of 1.4 μmol. Inter-laboratory and inter-technique comparisons show that the total uncertainty incorporating both the precision and accuracy of this method is better than 0.007%. Furthermore, ten seawaters sampled from different locations have a narrow δ37Cl value range from -0.008% to 0.010%, with a mean value of (0.000±0.006)%. This supports the assumption that any seawater can be representative of standard mean ocean chloride (SMOC) and used as an international reference material. 展开更多
关键词 chlorine stable isotope continuous flow isotope ratio mass spectrometry CF-IRMS GasBench
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Psychosocial stress and liver disease status 被引量:8
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作者 Cristin Constantin Vere Costin Teodor Streba +2 位作者 Letitia Maria Streba Alin Gabriel Ionescu Felix Sima 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第24期2980-2986,共7页
"Psychosocial stress" is an increasingly common concept in the challenging and highly-demanding modern society of today. Organic response to stress implicates two major components of the stress system, namel... "Psychosocial stress" is an increasingly common concept in the challenging and highly-demanding modern society of today. Organic response to stress implicates two major components of the stress system, namely the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Stress is anamnestically reported by patients during the course of disease, usually accompanied by a decline in their overall health status. As the mechanisms involving glucocorticoids and catecholamines have been deciphered, and their actions on immune cell function deeper understood, it has become clear that stress has an impact on hepatic inflam-matory response. An increasing number of articles have approached the link between psychosocial stress and the negative evolution of hepatic diseases. This article reviews a number of studies on both human populations and animal models performed in recent years, all linking stress, mainly of psychosocial nature, and the evolution of three important liver-related pathological entities: viral hepatitis, cirrhosis and hepatocellular carcinoma. 展开更多
关键词 STRESS Chronic viral hepatitis CIRRHOSIS CARCINOMA HEPATOCELLULAR Liver pathology
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Source and composition of sedimentary organic matter in the head of Three Gorges Reservoir: a multiproxy approach using δ^(13)C,lignin phenols, and lipid biomarker analyses 被引量:4
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作者 He Ding Changfeng Zhu +3 位作者 Kai Zhang Shangbin Xiao Xingqian Cui Yongge Sun 《Acta Geochimica》 EI CAS CSCD 2017年第3期452-455,共4页
A multiproxy approach including bulk organic carbon, δ^(13) C, lignin phenols, and lipid biomarker analyses were applied to characterize the source and composition of sedimentary organic matter in the head part of Th... A multiproxy approach including bulk organic carbon, δ^(13) C, lignin phenols, and lipid biomarker analyses were applied to characterize the source and composition of sedimentary organic matter in the head part of Three Gorges Reservoir. OM consisted of both natural(autochthonous and allochthonous) and anthropogenic inputs.The natural OM included input from vascular plants,especially non-woody angiosperms. The allochthonous input included plankton and microbial production, likely due to localized eutrophication. Anthropogenic inputs likely derived from petroleum input and/or urban activities.Other anthropogenic inputs were untreated sewage waste.These influences were concluded to be regionally specific point sources of pollution based on relative distributions and on the fact that molecular characteristics of sedimentary OM were not distributed smoothly along a gradient. 展开更多
关键词 Three Gorges reservior Sedimentary organic matter Δ^13C Lignin phenols Lipid biomarkers
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Study of the Psychological Problems of College Students
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作者 Li Li 《International English Education Research》 2014年第3期126-128,共3页
Good psychological quality is an integral part of the overall quality of the contemporary college students, which is also an important foundation for their healthy growth and success. However, according to the investi... Good psychological quality is an integral part of the overall quality of the contemporary college students, which is also an important foundation for their healthy growth and success. However, according to the investigation, in reality, many college students have various degrees of psychological problems, seriously affecting their normal learning and living. This article makes an in-depth discussion based on the analysis of contemporary college students' psychological quality system; in order to strengthen the mental health education and improve the students' adaptability. 展开更多
关键词 College Students Mental Health PROBLEM RESEARCH
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The Study on Improving the Health Condition through Sports
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作者 Senlin LU Yi HUAI 《International Journal of Technology Management》 2015年第6期113-115,共3页
In the 1990s, China began to develop mass sports, it is committed to improving the health condition, and it will improve the sport as an important form of universal health. While national sports development, China' s... In the 1990s, China began to develop mass sports, it is committed to improving the health condition, and it will improve the sport as an important form of universal health. While national sports development, China' s sports begin to flourish and have achieved remarkable record. For example, in the just-concluded 2014, in the Incheon Asian Games, China has made a total score first. This shows that sports have become an important part of national development to be reckoned with. With economic development, the accelerated pace of life is by the people neglect their own physical exercise, so that declining physical fitness, health groups continues to grow. So how in the development of sports at the same time, ensure the health sciences to improve the health condition. This paper discusses this correlation. 展开更多
关键词 SPORTS FITNESS Research
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Thinkings on Narrowing the Music Education Gap Between Urban and Rural Areas--On the Case of the Urban and Rural Music Education in Gaocheng, Hebei Province
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作者 Huifen Zhao Lei Zhang 《International Journal of Technology Management》 2013年第4期76-78,共3页
Nowadays, the development of quality education has always been attached great importance in China, of which the music education has been an important part. However, serious polarization of the urban and rural basic mu... Nowadays, the development of quality education has always been attached great importance in China, of which the music education has been an important part. However, serious polarization of the urban and rural basic music education leads to all sorts of differences, thus seriously affecting the overall improvement of quality of all people. To find out the problems and the reasons of the backward in rural basic music education, this paper makes an analysis of the differences between urban and rural basic education development through a survey and a study of basic situation in music education of urban and rural elementary school in Gaocheng, Hebei province, and then puts forward thinkings and suggestions about narrowing the urban-rural music education gap on the basis of the analysis of internal and extemal problems. 展开更多
关键词 music education the gap between urban and rural areas LITERACY reasons and suggestions.
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Accurate and precise determination of lead isotope composition in selected geochemical reference materials 被引量:2
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作者 Guangliang Wu Jian-Ming Zhu +3 位作者 Decan Tan Guilin Han Lixing Zhang Kun Ren 《Acta Geochimica》 EI CAS CSCD 2017年第3期421-425,共5页
Lead(Pb)isotopes have been extensively employed in tracing sources of Pb and its transport pathways through the environment.However,Pb isotopic ratios in related geochemical reference materials are scarce.Here,we repo... Lead(Pb)isotopes have been extensively employed in tracing sources of Pb and its transport pathways through the environment.However,Pb isotopic ratios in related geochemical reference materials are scarce.Here,we report high-precision Pb isotopic ratios measured by Nu Plasma II MC-ICP-MS using calibrated ^(205)Tl/^(203)Tl=2.38865(NIST SRM 997)for mass discrimination correction.The long-term external precision(2SD)for NISTSRM 981 of Pb,BCR-2,and BHVO-2 are 0.31‰(n=105),0.42‰(n=11),and 0.25‰(n=5)for ^(208)Pb/ ^(206)Pb and 0.16‰,0.53‰,and 0.07‰for ^(206)Pb/ ^(207)Pb,both respectively,and their Pb isotopic ratios are in excellent agreement with the recommended values.Using this method,we report for the first time Pb isotopic compositions in shale SGR-1b(USGS);coal CLB-1(USGS);stream sediments GSD-17,-21,and-23(IGGE);soils GSS-12,-13,-14,-15,and-16(IGGE);plants GSV-1,-2,and-3(IGGE);and human hair GSH-1(IGGE). 展开更多
关键词 Lead isotopes Geochemical reference materials MC-ICP-MS
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Problems and Countermeasures of Art Education in Medical Universities under the Background of Education Reform
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作者 Zhou ziwei Peng Lei 《International English Education Research》 2015年第5期92-94,共3页
Art education is an important part of the comprehensive implementation of quality-oriented education, and it is an important method for medical students to recognize perceptual world, to enrich their thoughts and feel... Art education is an important part of the comprehensive implementation of quality-oriented education, and it is an important method for medical students to recognize perceptual world, to enrich their thoughts and feelings, and to regulate their physical and mental health, so it is very important for the growth of medical students under the background of education reform. Based on the analysis of the existing problems of art education in medical universities, this paper points out the importance of art education for medical students in medical universities, and tries to make some countermeasures and suggestions to strengthen the art education for medical students. 展开更多
关键词 Medical University Art Education Education Reform
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Construction and Implementation of Practice Teaching System of English Major in Local Normal Universities 被引量:1
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作者 Nannan Sun 《International Journal of Technology Management》 2013年第7期13-14,共2页
English practice teaching has outstanding superiority over the extension and supplementation of English classroom teaching, and practice teaching is an indispensably important part of college English teaching. To stud... English practice teaching has outstanding superiority over the extension and supplementation of English classroom teaching, and practice teaching is an indispensably important part of college English teaching. To students, cultivation of the ability of practice is vital, affecting students' employment and future. To universities, teaching quality has a direct impact on the development prospect of schools and decides the future of schools. Moreover, local normal universities also undertake a more important task to cultivate local high-quality talents teaching primary and junior high schools. These teaching talents undertake the great task of English teaching over primary and junior high school students, and thus the construction and implementation of practice teaching system of English major in normal universities are urgent. 展开更多
关键词 LOCAL Normal universities ENGLISH PRACTICE Teaching system.
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Compatibility of the Support System Consisting of Yielding Elements and Shotcrete Lining in Highly Faulted Grounds
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作者 Tina Marolt Cebasek Jakob Likar 《Journal of Civil Engineering and Architecture》 2014年第11期1457-1466,共10页
The design procedure is made for a mine shaft where permanent underground facilities are interconnected. The highly faulted grounds were identified using empirical and semi-empirical theories. Furthermore, the behavio... The design procedure is made for a mine shaft where permanent underground facilities are interconnected. The highly faulted grounds were identified using empirical and semi-empirical theories. Furthermore, the behavior types are presented. This paper presents excavation and support methods in such ground conditions and the calculations results show that the installation of the yielding elements have an effect on support elements and prevent shotcrete damage during the curing stage. Different numerical analyses carried out showed that, with the yielding elements installed, the total displacements increase but the final axial force reduces, and therefore, the characteristic compressive strength of shotcrete is not exceeded. The calculation results of ground loads and displacements on the designed support system are presented with a 3D numerical geo-mechanical model adopted for highly faulted ground surrounding deeper complex underground structures. 展开更多
关键词 Faulted ground yielding elements mine shaft 3D numerical model ground reaction curve.
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On the status and role of social sports in urban development
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作者 Zhihong Zheng 《International Journal of Technology Management》 2015年第7期46-48,共3页
The importance of social sports in urban development show that it makes the quality of urban residents greatly improved and becomes a strong surge of power to promote the development of economy; it makes the cultural ... The importance of social sports in urban development show that it makes the quality of urban residents greatly improved and becomes a strong surge of power to promote the development of economy; it makes the cultural connotations of the city more abundant and becomes the propeller of urban cultural development. And the specific roles show that it forms the group of physical and mental health in the city; it makes sports become an important part of people' s lives; it cultivates and enhances the citizens' sense of honor; it improves the urban management and enhances the image of the city. 展开更多
关键词 urban development social sports STATUS ROLE
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Study on teaching quality of music teachers in colleges under quality education background
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作者 Na Wang 《International English Education Research》 2014年第9期13-16,共4页
Aesthetic education is the important component of the character building education, but music education is an important means to implement character building education, train more university students with quality of a... Aesthetic education is the important component of the character building education, but music education is an important means to implement character building education, train more university students with quality of aesthetic education today when could be recommending character building education in a more cost-effective manner, the music teacher's quality is the key point. The main visual angle of this text is in term of training university student's character building education, canvass the teaching quality which the music teacher of the university should possess under the character building education background. 展开更多
关键词 Aesthetic education Teaching quality ABILITY
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Volatile and C-H-O isotopic compositions of giant Fe-Ti-V oxide deposits in the Panxi region and their implications for the sources of volatiles and the origin of Fe-Ti oxide ores 被引量:15
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作者 WANG Christina Yan 《Science China Earth Sciences》 SCIE EI CAS 2012年第11期1782-1795,共14页
The Panzhihua,Hongge,and Baima Fe-Ti-V oxide deposits in the Panzhihua-Xichang(Panxi) region are hosted in large layered mafic-ultramafic intrusions.The layered intrusions intrude either the Neoproterozoic Dengying Fo... The Panzhihua,Hongge,and Baima Fe-Ti-V oxide deposits in the Panzhihua-Xichang(Panxi) region are hosted in large layered mafic-ultramafic intrusions.The layered intrusions intrude either the Neoproterozoic Dengying Formation,composed mainly of limestone,or the Paleoproterozoic Hekou Formation,composed of meta-sedimentary-volcanic rocks.It remains unclear if the wall rocks have been involved during the fractionation of magmas and have affected the sequence of crystallization of Fe-Ti oxide.Volatiles and their C-H-O isotopic compositions of magnetite,apatite,clinopyroxene,and plagioclase of different types of ores from the three intrusions are analyzed using a technique of stepwise heating mass spectrometer to evaluate the role of wall rocks in the formation of Fe-Ti oxide ores.Volatiles released from magnetite are composed mainly of H 2 O and CO 2,whereas the other minerals are composed mainly of H 2 O,CO 2 and H 2.At 800-1200°C temperature interval,the average 13 C values of CO 2 of all the minerals from the three intrusions range from 7.7‰ to 13.5‰ and the average 18 O CO 2 values from 19.1‰ to 19.5‰,which are scattered in a mixed field with basalt and the two types of wall rocks as end-members,indicating that CO 2 from the wall rocks may have been involved in the magmas from which the three intrusions formed.At 400-800 C temperature interval,both 13 C values(13.7‰ to 17.9‰ on the average) and 18 O values(16.2‰ to 19.2‰ on the average) of CO 2 of all the minerals are lower than those for 800-1200 C temperature interval,and much closer to the values of the wall rocks.Abundant H 2 O released at the 400-800 C temperature interval has relatively low D values ranging from 90‰ to 115‰,also indicating the involvement of fluids from the wall rocks.The average bulk contents of volatiles released from magnetite of the Hongge,Baima,and Panzhihua intrusions are 4891,2996,and 1568 mm 3 STP/g,respectively,much higher than those released from other minerals in total,which are 382,600,and 379 mm 3 STP/g,respectively,indicating that magnetite crystallized from magmas with much more volatiles than other minerals.This can be interpreted as that crystallization of clinopyroxene and plagioclase in the early fractionation of magmas resulted in volatiles such as H 2 O that were eventually enriched in the residual magmas and,at the same time,fluids from the wall rocks may have been involved in the magmas and were trapped in magnetite,which crystallized later than clinopyroxene and plagioclase. 展开更多
关键词 magnetite VOLATILES C-H-O isotope Fe-Ti-V oxide ore Panxi region
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High precision in-situ Pb isotopic analysis of sulfide minerals by femtosecond laser ablation multi-collector inductively coupled plasma mass spectrometry 被引量:16
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作者 YUAN HongLin YIN Cong +7 位作者 LIU Xu CHEN KaiYun BAO ZhiAn ZONG ChunLei DAI MenNing LAI ShaoCong WANG Rong JIANG ShaoYong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第10期1713-1721,共9页
An in-situ microanalysis of Pb isotopic compositions in sulfide minerals is carried out by using femtosecond laser-ablation multi-collector inductively coupled plasma mass spectrometry (fsLA-MC-ICP-MS). High-tempera... An in-situ microanalysis of Pb isotopic compositions in sulfide minerals is carried out by using femtosecond laser-ablation multi-collector inductively coupled plasma mass spectrometry (fsLA-MC-ICP-MS). High-temperature-activated carbon was used to filter Hg contained in the carrier gas, which reduced the Hg background signal by 48% and also lowered the detection limit of the analysis. Fractionation and mass discrimination effects existing in the ICP-MS analytical processes were corrected using an internal reference T1 in conjunction with an external reference NIST SRM 610. The proposed method was used to an- alyze the Pb isotopic compositions of chalcopyrite, pyrite, and sphalerite from the Dulong Sn-Zn-In polymetallic ore district. The results showed that in this ore district, the sulfide minerals and different grains of the same sulfide mineral show a large variation in Pb content up to 1000-fold. The studied pyrites show relatively higher Pb contents and homogeneous Pb isotopic compositions, whereas the sphalerites have low Pb contents but most variable Pb isotopic compositions. It is suggested that the large variation of Pb isotopic composition may reflect a late hydrothermal superimposition on the primary sulfide formation. In addition, radiogenic Pb accumulated by radioactive decay of trace amounts of U over time in the host minerals may also be one of the causes for the large variation range of Pb content and Pb isotopic composition of those low-Pb sphalerites. Chalcopyrite and sphalerite grains with Pb content greater than 10 ppm presented a consistent Pb isotopic distribution, whereas all the sulfide grains with Pb content greater than 100 ppm had consistent Pb isotopic composition within 2s measurement uncertainties. The in-situ analysis of Pb isotopic composition agreed well with the results obtained by conventional chemical methods within 2s measurement uncertainties, indicating that the data obtained by fsLA-MC-ICP-MS are reliable. Additionally, this study indicates that the Pb isotopic composition could truthfully record the source of ore-forming minerals only for sulfide minerals with high Pb content. On the contrary, the Pb isotopic composition of low-Pb sulfide minerals may be affected by trace amounts of U in the host minerals that may lead to a highly radiogenic Pb isotope ratio. Alternatively, it is also possible that late fluid metasomatic overprinting may alter the Pb isotopic compositions. 展开更多
关键词 femtosecond laser ablation MC-ICP-MS lead isotopes lead concentration SULFIDE
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Petrogenesis of the concealed Daqiling intrusion in Guangxi and its tectonic significance: Constraints from geochemistry, zircon U-Pb dating and Nd-Hf isotopic compositions 被引量:8
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作者 ZHANG HuaiFeng LU JianJun +3 位作者 WANG RuCheng MA DongSheng ZHU JinChu ZHANG RongQing 《Science China Earth Sciences》 SCIE EI CAS 2014年第8期1723-1740,共18页
The samples from the hidden Daqiling muscovite monzonite granite, which has recently been recognized within the Limu Sn-polymetallic ore field, have been analyzed for zircon U-Pb ages and whole rock geochemical and Nd... The samples from the hidden Daqiling muscovite monzonite granite, which has recently been recognized within the Limu Sn-polymetallic ore field, have been analyzed for zircon U-Pb ages and whole rock geochemical and Nd-Hf isotopic compositions to discuss its genesis, source, and tectonic setting. LA-ICP-MS zircon U-Pb dating indicates that the granite crystallized in the late Indosinian(224.8±1.6 Ma). The granite is enriched in SiO2 and K2 O and low in CaO and Na2 O. It is strongly peraluminous with the A/CNK values of 1.09–1.20 and 1.4 vol%–2.7 vol% normal corundum. Chondrite-normalized REE patterns show slightly right-dipping shape with strongly negative Eu anomalies(δEu =0.08–0.17). All samples show enrichment of LILEs(Cs, Rb and K) and HFSEs(U, Pb, Ce and Hf), but have relatively low contents of Ba, Sr and Ti. The zircon saturation temperatures(Tzr) are from 711 to 740°C, which are slightly lower than the average value of typical S-type granite(764°C). The granite has negative εNd(t) and εHf(t) values, which change from ?9.1 to ?10.1 with the peak values of ?9.2 to ?9.0 and from ?3.7 to ?12.6 with the peak values of ?6 to ?5, respectively. The C DMT(Nd) and C DMT(Hf) values are 1.74–1.82 Ga with the peak values of 1.73–1.75 Ga and 1.49–2.04 Ga with the peak values of 1.5–1.6 Ga, respectively. These characteristics reveal that the source region of the granite is dominantly late Paleoproterozoic to early Mesoproterozoic crustal materials. Seven inherited magmatic zircons are dated at the age of 248.6±4.3 Ma, which suggests the existence of the early Indosinian granite in Limu area. These zircons have the εHf(t) values of ?6.7– ?2.3, similar to those of the Daqiling granite, implying the involvement of the early Indosinian granite during the formation of the Daqiling granite. Inherited zircon of 945±11 Ma has the εHf(t) and TDM(Hf) values of 8.7 and 1.14 Ga, respectively, compatible with those of the Neoproterozoic arc magmatic rocks in the eastern Jiangnan orogenic belt. Therefore we inferred that Neoproterozoic arc magma might have been involved in the formation of the Daqiling granite, and that the Neoproterozoic arc magma belt and continent-arc collision belt between the Yangtze and Cathaysia Blocks might have extended westsouthward to Limu region. It is proposed that the underplating of mantle materials triggered by crustal extension and thinning resulted in partial melting of crustal materials to form the Daqiling granite in the late Indosinian under post-collisional tectonic setting. 展开更多
关键词 Daqiling concealed granite zircon U-Pb dating Nd-Hf isotopic compositions petrology and geochemistry POST-COLLISION
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Zircon U-Pb geochronology, Hf isotopic composition, and geological implications of the Neoproterozoic meta-sedimentary rocks in Suizhou-Zaoyang area, the northern Yangtze Block 被引量:3
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作者 YANG ZhenNing YANG KunGuang +3 位作者 XU Yang DENG Xin CHENG WanQiang LONG ZhaoYue 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第11期1910-1923,1-4,共14页
Suizhou-Zaoyang area is located in the southern Qinling-Tongbai-Dabie Orogen, China. A combined research on U-Pb ages and Lu-Hf isotopes for detrital zircons from three meta-sedimentary rocks in the Wudang Group is re... Suizhou-Zaoyang area is located in the southern Qinling-Tongbai-Dabie Orogen, China. A combined research on U-Pb ages and Lu-Hf isotopes for detrital zircons from three meta-sedimentary rocks in the Wudang Group is reported. The upper Wudang Group has a major age population of ca. 750 Ma and a sub-major of ca. 860 Ma. But the lower part only yields one age peak at ca. 2.03 Ga. In situ Lu-Hf analyses of the young age group of ca. 750 Ma for zircons from the upper Wudang Group yield an average εHt(t) value of -8.6 and two-stage Hf model ages (TDM2) from 1837 to 2230 Ma, respectively. However, zircons from the lower Wudang Group give an average εHf(t) value of 4.5 and TDM1 of 2220±22 Ma, close to the timing of zircon crystallization. Thus, it is suggested that, in the study area, the continental crust grew during the middle Paleoproterozoic and reworked during the middle Neoproterozoic, which shows the affinity to the Dabie Orogen. In addition, in the lower Wudang Group, two metamorphic zircon ages of 1992±91 and 1999±61 Ma are consistent with that of the middle Paleoproterozoic metamorphism event in the northern Yangtze Block, which may represent the assemblage of the Columbia Supercontinent. On the basis of the U-Pb ages and Hf isotopes, it is proposed that Suizhou-Zaoyang area was involved in the subduction-collision event in the middle Paleoproterozoic and the Yangtze Block was one of the components of the Paleo-Mesoproterozoic supercontinent. 展开更多
关键词 detrital zircon growth and reworking of continental crust middle Paleoproterozoic northern Yangtze Block Columbia Supercontinent
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Stability of proteins with multi-state unfolding behavior 被引量:5
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作者 YANG BinSheng SONG Zhen +1 位作者 ZHENG XiaoYan ZHAO YaQin 《Science China Chemistry》 SCIE EI CAS 2012年第7期1351-1357,共7页
A new model used to calculate the free energy change of protein unfolding is presented. In this model, proteins are considered to be composed of structural elements. The unfolding of a structural element obeys a two-s... A new model used to calculate the free energy change of protein unfolding is presented. In this model, proteins are considered to be composed of structural elements. The unfolding of a structural element obeys a two-state mechanism and the free energy change of the element can be obtained by a linear extrapolation method. If a protein consists of the same structural elements, its unfolding will displays a two-state process, and only the average structural element free energy change 〈△G0 element(H2O)〉 can be measured. If protein consists of completely different structural elements, its unfolding will show a multi-state behavior. When a protein consists of n structural elements its unfolding will shows a (n+1)-state behavior. A least-squares fitting can be used to analyze the contribution of each structural element to the protein and the free energy change of each structural element can be obtained by using linear extrapolation to zero denaturant concentration, not to the start of each transition. The measured △Gn protein(H2O) is the sum of the free energy change for each structural element. Using this new model, we can not only analyze the stability of various proteins with similar structure and similar molecular weight, which undergo multi-state unfolding processes, but also compare the stability of proteins with different structures and molecular weights using the average structural element free energy change 〈△G0 element(H2O)〉. Although this method cannot completely provide the exact free energy of proteins, it is better than current methods. 展开更多
关键词 new model protein stability multi-state unfolding CopC
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