检索结果-南通市图书馆

SHRIMP Zircon U-Pb Age of the Piqiang Layered Intrusion in the Tarim Large Igneous Province and Subducted Slab-Plume Interaction in Its Petrogenesis

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2018年第4期92卷 1651-1652页

作者： cao jun Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology School of Earth Sciences East China University of Technology

Objective During the Permian, at least four mafic continental large igneous provinces （LIPs） were tbrmed in eastern Asia, i.e., the Siberian traps （-251 Ma）, Emeishan LIP （-260 Ma）, Tarim LIP （-290-270 Ma） and Panjal traps （-290 Ma）（Shellnutt et al., 2015）. The Emeishan and Tarim LIPs in China are both known for the presence of several magmatic Fe-Ti-V oxide deposits hosted in layered mafic- ultramafic intrusions. The origin of such magmatic Fe-Ti- V oxide deposits is enigmatic. One of the long-lasting debates is the mechanism by which large amounts of Fe-Ti oxides accumulated in the layered intrusions. Regardless of mechanism, there is still considerable debate regarding the mantle source compositions of the Fe-Ti-V oxide ore- bearing intrusions, in the Tarim LIP, a giant Fe-Ti-V oxide deposit is hosted by the Piqiang layered intrusion at the northern margin of the Tarim block. This intrusion consists mainly of gabbro and minor plagioclase-bearing clinopyroxenite and anorthosite （Fig. l a）. For this study we present new SHRIMP zircon U-Pb age and whole-rock geochemical data for the Piqiang layered gabbroic intrusion to evaluate the nature of its possible source compositions, which in turn aids in understanding the formation of the giant Fe-Ti-V oxide deposit in the plume- related LIPs.

关键词： SHRIMP Zircon U-Pb Age of the Piqiang Layered Intrusion in the Tarim Large Igneous Province and Subducted Slab-Plume Interaction In Ta Pb

Genomic Analysis of Mitochondrial Carrier Genes in the Bombyx mori

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2012年第10期11卷 1707-1713页

作者： cao jun SHI Feng Institute of Life Science Jiangsu University Shandong Lvdu Bio-Technique Industry

This study is performed to investigate the mitochondrial carrier gene family in silkworm genome. In total, 30 genes are identified and claded into eight well-conserved groups. Gene duplication contributes to the expansion and complexity of this family. Diverse expression patterns suggest their functional differentiation. Analyses of the sitespecific profiles reveal critical amino acid residues for functional divergence. This study highlights the molecular evolution of the mitochondrial carrier gene family in silkworm and may provide a starting point for further experimental verification.

关键词： mitochondrial carrier gene phylogenetic analysis evolution silkworm

Wood species identification using spectral reflectance feature and optimal illumination radian design

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2016年第1期27卷 219-224页

作者： Peng Zhao jun cao Information and Computer Engineering College Northeast Forestry University College of Mechanical and Electronic Engineering Northeast Forestry University

We developed a scheme based on wood surface novel wood recognition spectral features that aimed to solve three problems. First was elimination of noise in some bands of wood spectral reflection curves. Second was improvement of wood feature selection based on analysis of wood spectral data. The wood spectral band is 350-2500 nm, a 2150D vector with a spectral sampling interval of 1 nm. We developed a feature selection proce- dure and a filtering procedure by solving the eigenvalues of the dispersion matrix. Third, we optimized the design for the indoor radian＇s mounting height. We used a genetic algorithm to solve the optimal radian＇s height so that the spectral reflection curves had the best classification infor- mation for wood species. Experiments on fivecommon wood species in northeast China showed overall recogni- tion accuracy 〉95 % at optimal recognition velocity.

关键词： Wood species identification Featureselection Radian Genetic algorithm Spectral analysis

降雨诱发国道G326顺层滑坡破坏与运动过程研究

在线全文

学校读者我要写书评

暂无评论

三峡大学学报（自然科学版） 2025年第1期47卷 44-49页

作者：刘仕洪宋琨郭磊曹俊姜波贵州省铜仁公路管理局贵州铜仁554200 三峡大学防灾减灾湖北省重点实验室湖北宜昌443002 贵州省交通规划勘察设计研究院股份有限公司贵阳550081

贵州省国道G326松桃县甘龙镇石板村田堡组顺层滑坡是2020年强降雨诱发的滑坡灾害.在对滑坡变形破坏特征调查的基础上,分析了强降雨诱发滑坡滑动破坏的成因.采用物质点法(materialpointmethod,MPM)进行了滑坡运动过程的模拟,揭示了滑坡... 详细信息

贵州省国道G326松桃县甘龙镇石板村田堡组顺层滑坡是2020年强降雨诱发的滑坡灾害.在对滑坡变形破坏特征调查的基础上,分析了强降雨诱发滑坡滑动破坏的成因.采用物质点法(materialpointmethod,MPM)进行了滑坡运动过程的模拟,揭示了滑坡运动的速度和冲击荷载等变化规律.结果表明:国道G326滑坡是受2020年7月8日的强降雨诱发的中型顺层岩质滑坡,在8日4时的小时降雨量为96.2mm后约3h发生整体滑移破坏;物质点法能够较真实地模拟滑坡的运动、堆积过程,模拟的堆积体形态与滑坡破坏调查情况基本一致;滑坡岩土体的最大滑动速度为27m/s,最大滑动动能为1.8×109J(15s左右),最大冲击力为37.98×106kN,位于距滑坡后缘约230m处.该研究对国道G326沿线类似滑坡灾害的风险防控具有参考价值和工程借鉴意义.

关键词：降雨滑坡顺层滑动运动过程模拟物质点法冲击荷载

Petrogenesis and Metallogenesis of the Mazaertag Layered Intrusion in the Tarim Large Igneous Province,NW China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2017年第5期91卷 1653-1679页

作者： cao jun WANG Qimeng Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology Nanchang 330013 Jiangxi China School of Earth Sciences East China University of Technology Nanchang 330013 Jiangxi China NO.1 Institute of Geology and Mineral Resources Survey of Henan Luoyang 471023 Henan China

The Mazaertag layered intrusion is located in the northwestern part of the Tarim large igneous province where several early Permian layered mafic-ultramafic intrusions host important Fe-Ti oxide deposits. The intrusion covers an area of -0.13 km-2 and has a vertical stratigraphic thickness of at least300 m. It consists chiefly of olivine clinopyroxenite, and is cut through by the nearby mafic-ultramafic dykes. In this paper, we report new mineral chemistry data and whole-rock chemical and isotopic compositions for the Mazaertag intrusion along with whole-rock isotopic compositions for the nearby mafic dykes. The averaged compositions of cumulus olivine, clinopyroxene and intercumulus plagioclase within individual samples range from Fo71-73,Mg^# = 76 to 79 and An65-75 but they do not define sustained reversals. The observed mineral compositions are consistent with the differentiation of a single batch of magma in a closed system. Rocks of the Mazaertag intrusion are characterized by enrichment in light REE relative to heavy REE, positive Nb and Ta anomalies and a small range of age-corrected εNd（t）（-0.1 to ＋0.9） and initial ^87Sr/^86Sr values（0.7044 to 0.7068）. The slightly lower εNdt）, initial ^206Pb/^204Pb and higher initial ^87Sr/^86Sr values of the intrusion compared to those of the least contaminated dykes[εNdt） =＋2.8 to ＋3.4;^206Pb/^204Pb）i = 18.516-18.521;（^87Sr/^86Sr）i = 0.7038-0.7041] imply that the Mazaertag magma was subjected to small to modest degrees of contamination by the upper crust. The Sr-Nd isotopic compositions of the least contaminated dykes are consistent with derivation from a FOZO-like mantle source. The parental magma of the Mazaertag intrusion, estimated from clinopyroxene compositions using mineral-melt partition coefficients, has trace element compositions similar to some of the most primitive mafic dykes in the same area. This suggests that the Mazaertag intrusion and mafic dykes shared a similar mantle source. Therefore, the parental ma

关键词： clinopyroxene Fe-Ti oxide layered intrusion Mazaertag Tarim large igneous province

^(40)Ar/^(39)Ar Geochronology of the Late Paleozoic Woniusi Basalts from the Baoshan Terrane, SW China:Implications for the Rifting of the Northern Margin of Gondwana

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2018年第3期92卷 1276-1278页

作者： cao jun Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology School of Earth Sciences East China University of Technology

Objective Although the occurrence of Late Paleozoic rifting on the northern margin of Gondwana is widely accepted,the precise reason for the rifting is not *** Woniusi basalts in the Baoshan terrane cover an area of～... 详细信息

关键词： Implications for the Rifting the Northern Margin of Gondwana

在线全文

学校读者我要写书评

暂无评论

太湖底泥磷释放量及释放规律的研究综述

湖泊科学 2025年第1期37卷 14-35页

作者：朱伟侯豪刘环许小格朱瑜星陈诺曹俊林乃喜河海大学环境学院南京210098 河海大学土木与交通学院南京210098 河海大学水科学研究院南京210098

太湖是我国最为重要的湖泊之一,是国家湖泊治理的重点。自2007年水危机以来,太湖治理累计投入超2620亿元,是世界上治理力度最大的湖泊。2016年以来太湖出现磷反弹,2020年开始显著好转,2023年水华减少。太湖蓝藻水华与磷的响应相对显著,... 详细信息

太湖是我国最为重要的湖泊之一,是国家湖泊治理的重点。自2007年水危机以来,太湖治理累计投入超2620亿元,是世界上治理力度最大的湖泊。2016年以来太湖出现磷反弹,2020年开始显著好转,2023年水华减少。太湖蓝藻水华与磷的响应相对显著,回顾太湖磷十余年来的研究,关于底泥内源释放对水体总磷贡献的说法不一,这对于太湖整体磷负荷的认识及内源治理措施的制定产生了重要影响。针对太湖底泥磷的源汇、释放量以及释放规律,本文对国内外关于湖泊底泥磷释放的监测、实验、计算等研究进行系统回顾,对关于太湖底泥释放方面的研究进行梳理。通过比较和分析,尝试形成对太湖底泥磷释放规律和范围的一些基本认识。通过综述总结提出了“总源”“总汇”“净源”“净汇”的概念,并对可能成为“净源”的5个过程的发生条件和释放强度进行分析。认为Fick扩散释放是可以恒常性发生的过程,而在具备条件才发生的过程中,DO<2 mg/L后出现的磷还原释放是比较主要的过程,需要重点关注。“净源”是否发生应该依据实际湖泊的环境条件开展动态释放实验来判断。太湖目前虽然处于“总汇”状态,但“净源”是显著存在的,明确“净源”存在的位置和发生的时段对于太湖内源治理非常重要。

关键词：太湖底泥磷释放源汇质量平衡释放实验

Effect of water injection on hydrogen generation during severe accident in PWR

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2009年第5期20卷 312-316页

作者： TAO jun cao Xuewu School of Mechanical and Power Engineering Shanghai Jiao Tong University Shanghai 200240 China

Effect of water injection on hydrogen generation during severe accident in a 1000 MWe pressurized water reactor was studied. The analyses were carried out with different water injection rates at different core damage stages. The core can be quenched and accident progression can be terminated by water injection at the time before cohesive core debris is formed at lower core region. Hydrogen generation rate decreases with water injection into the core at the peak core temperature of 1700 K, because the core is quenched and reflooded quickly. The water injection at the peak core temperature of 1900 K, the hydrogen generation rate increases at low injection rates of the water, as the core is quenched slowly and the core remains in uncovered condition at high temperatures for a longer time than the situation of high injection rate. At peak core temperature of 2100–2300 K, the Hydrogen generation rate increases by water injection because of the steam serving to the high temperature steam-starved core. Hydrogen generation rate increases significantly after water injection into the core at peak core temperature of 2500 K because of the steam serving to the relocating Zr-U-O mixture. Almost no hydrogen generation can be seen in base case after formation of the molten pool at the lower core region. However, hydrogen is generated if water is injected into the molten pool, because steam serves to the crust supporting the molten pool. Reactor coolant system (RCS) depressurization by opening power operated relief valves has important effect on hydrogen generation. Special attention should be paid to hydrogen generation enhancement caused by RCS depressurization.

关键词： PWR 核技术研究发展 RCS

Neutrino oscillation： discovery and perspectives

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2016年第1期61卷 48-51页

作者： jun cao Miao He Institute of High Energy Physics Beijing 100049 China

Takaaki Kajita from Japan and Arthur *** Donald from Canada shared the 2015 Nobel Prize in Physics,‘‘for the discovery of neutrino oscillations,which shows that neutrinos have mass’’.Neutrinos are elementary particles with zero mass in the Standard Model of particle ***1998,Takaaki Kajita,on behalf of the Super-Kamiokande collaboration,showed a smoking gun evidence of

关键词：中微子振荡诺贝尔物理学奖基本粒子物理学展望大气中微子零质量圆锥花序标准模型