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党执政能力建设视阈下的核心意识研究
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作者 王玉堂 《湖南涉外经济学院学报》 2019年第1期46-52,共7页
增强核心意识,维护核心权威,是马克思主义政党执政能力建设的一个重要维度。增强核心意识,最根本的是做到'两个坚决维护'。共产党人的核心意识不是自发形成的,而是以坚定的理想信念作支撑,在长期的学习、实践、党性锻炼和政治... 增强核心意识,维护核心权威,是马克思主义政党执政能力建设的一个重要维度。增强核心意识,最根本的是做到'两个坚决维护'。共产党人的核心意识不是自发形成的,而是以坚定的理想信念作支撑,在长期的学习、实践、党性锻炼和政治历练中逐步形成的,有着深厚的思想、政治和道德底蕴。增强核心意识,是一个政治命题,也是一个实践命题,必须体现在具体工作中和实际行动上。 展开更多
关键词 执政能力 核心 核心意识 领导核心
Approach to 2′-(Dialkylamino)-1-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 1,3-Oxazin-4-ones via Cyclization of Vilsmeier Salts withα-Hydroxy andβ-Carbonyl Amides
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作者 DAI Jianan LIU Bengen +4 位作者 WEI Zhonglin CAO Jungang LIANG Dapeng DUAN Haifeng LIN Yingjie 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第2期216-220,共5页
A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been ... A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been developed from a-hydroxy andβ-carbonyl amides and various Vilsmeier salts.A wide range of heterocyclic compounds were obtained in excellent yields(up to 97%),which will provide promising candidates lor chemical biology and drug discovery. 展开更多
关键词 SPIROOXINDOLE unit 2-Oxazolin-4-ones CORE STRUCTURE 3-Oxazin-4-ones CORE STRUCTURE
On Characterizations of Special Elements in Rings with Involution
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作者 Sanzhang XU Jianlong CHEN Dijana MOSIC 《数学年刊:B辑英文版》 SCIE CSCD 2019年第1期65-78,共14页
Let R be a ring with involution. It is well-known that an EP element in R is a core invertible element, but the question when a core invertible element is an EP element,the authors answer in this paper. Several new ch... Let R be a ring with involution. It is well-known that an EP element in R is a core invertible element, but the question when a core invertible element is an EP element,the authors answer in this paper. Several new characterizations of star-core, normal and Hermitian elements in R are also presented. 展开更多
关键词 Moore-Penrose INVERSE Core INVERSE EP ELEMENT Star-core ELEMENT Normal ELEMENT HERMITIAN ELEMENT
辽河油田D66块火驱开发储层取心技术 预览
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作者 石林 《石油钻采工艺》 CAS 北大核心 2019年第2期143-146,共4页
为了提高火驱开发地层岩心收获率,分析了火驱对D66块地层的影响,在此基础上,有针对性地对取心工具进行了改进,对钻井参数进行了优化,并完成了3口井的取心实践。研究表明,火驱对D66块杜家台油层改造作用较大,主要表现在3个方面:一是火驱... 为了提高火驱开发地层岩心收获率,分析了火驱对D66块地层的影响,在此基础上,有针对性地对取心工具进行了改进,对钻井参数进行了优化,并完成了3口井的取心实践。研究表明,火驱对D66块杜家台油层改造作用较大,主要表现在3个方面:一是火驱导致地层温度大幅度升高;二是高温烘烤作用使蒙皂石快速脱水后,遇水快速膨胀,胶结物因此裂开失去胶结作用,导致地层变得松散;三是火驱形成的高温强碱环境,使岩石骨架颗粒石英发生溶解,导致地层变得松散甚至垮塌。针对火驱后的高温松散地层综合应用耐高温密闭液、防冲蚀钻头、复合式岩心爪、铝合金内筒和PVC内衬管等取心工具,结合“高钻压、低钻速、小排量”的钻井参数设计,岩心收获率可以达到77.96%~88.32%,比常规取心提高约44~54.36个百分点。本文旨在通过对D66块火驱后地层取心的成功经验进行总结,为其他地区火驱后地层的取心提供借鉴。 展开更多
关键词 岩心 火驱 火烧油层 取心 收获率 辽河油田
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The effect of the differential rotation of the earth inner core on the free core nutation
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作者 Mian Zhang Chengli Huang 《大地测量与地球动力学:英文版》 2019年第2期146-149,共4页
Seismic observations shows that the inner core rotates faster than the mantle and the rotation axis of the inner core may not align with the rotation axis of the mantle. Free core nutation reflects core’s information... Seismic observations shows that the inner core rotates faster than the mantle and the rotation axis of the inner core may not align with the rotation axis of the mantle. Free core nutation reflects core’s information. We discuss the effect of the inner core’s differential rotation on free core nutation from two aspects: rotation speed and deflection angle. Our result shows it is in accordance with the observations when the inner core’s rotation speed doesn’t exceed 10° faster than mantle’s per year, and the deflection angle is less than 1°,if the rotation speed and the deflection angle are respectively considered separately. 展开更多
关键词 INNER CORE DIFFERENTIAL ROTATION Free CORE NUTATION
Hepatitis C virus antigens enzyme immunoassay for one-step diagnosis of hepatitis C virus coinfection in human immunodeficiency virus infected individuals 预览
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作者 Ke-Qin Hu Wei Cui +1 位作者 Susan D Rouster Kenneth E Sherman 《世界肝病学杂志:英文版(电子版)》 2019年第5期442-449,共8页
BACKGROUND Current diagnosis of hepatitis C virus(HCV)infection requires two sequential steps:testing for anti-HCV followed by HCV RNA PCR to confirm viremia.We have developed a highly sensitive and specific HCV-antig... BACKGROUND Current diagnosis of hepatitis C virus(HCV)infection requires two sequential steps:testing for anti-HCV followed by HCV RNA PCR to confirm viremia.We have developed a highly sensitive and specific HCV-antigens enzyme immunoassay(HCV-Ags EIA)for one-step diagnosis of viremic HCV infection.AIM To assess the clinical application of the HCV-Ags EIA in one-step diagnosis of viremic HCV infection in human immunodeficiency virus(HIV)-coinfected individuals.METHODS The study blindly tested HCV-Ags EIA for its performance in one-step diagnosing viremic HCV infection in 147 sera:10 without HCV or HIV infection;54 with viremic HCV monoinfection;38 with viremic HCV/HIV coinfection;and 45 with viremic HCV and non-viremic HIV coinfection.RESULTS Upon decoding,it was 100%accordance of HCV-Ags EIA to HCV infection status by HCV RNA PCR test.In five sera with HCV infection,HCV RNA was as low as 50-59 IU/mL,and four out of five tested positive for HCV-Ags EIA.Likewise,it was also 100%accordance of HCV-Ags EIA to HCV infection status by HCV RNA PCR in 83 sera with HCV and HIV coinfection,regardless if HIV infection was active or not.CONCLUSION The modified HCV-Ags EIA has a lower detection limit equivalent to serum HCV RNA levels of approximately 100 IU/mL.It is highly sensitive and specific in the setting of HIV coinfection,regardless of HIV infection status and CD4 count.These data support the clinical application of the HCV-Ags EIA in one-step diagnosis of HCV infection in HIV-infected individuals. 展开更多
关键词 HEPATITIS C VIRUS HEPATITIS C VIRUS ANTIGENS HEPATITIS C VIRUS core antigen HEPATITIS C VIRUS DIAGNOSTIC test DIAGNOSTIC assay Enzyme immunoassay
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Analysis of drying and saturating natural gypsum samples for mechanical testing 预览
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作者 Mohammadhossein Sadeghiamirshahidi Stanley J.Vitton 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第2期219-227,共9页
The stability of underground abandoned gypsum mines is dependent on the gypsum pillar’s strength,and most abandoned mines are in a fully saturated condition.Moisture affects the strength of gypsum and is therefore co... The stability of underground abandoned gypsum mines is dependent on the gypsum pillar’s strength,and most abandoned mines are in a fully saturated condition.Moisture affects the strength of gypsum and is therefore commonly measured when testing rock strength.For most rocks,this is a simple task of weighing the rock’s mass before and after oven-heating at a specified temperature and duration.For natural gypsum,however,this is not a straightforward process.Heating natural gypsum can result in dehydration and transformation of gypsum to hemihydrate and anhydrite,thus changing the physical characteristics of the gypsum such as its particle density which in turn affects the moisture content and strength measurements.To prevent transformation when determining the moisture content of gypsum,the American Society for Testing Materials(ASTM)recommends lowering the drying temperature from 110℃to 60℃.To investigate the temperature at which gypsum transforms to hemihydrate,we used a helium pycnometer to measure the particle densities of gypsum,hemihydrate and anhydrite.In this research,we suggest that a higher drying temperature of 80℃can be used for drying gypsum without transforming gypsum to hemihydrate.Further,preparing saturated samples for mechanical testing,which is required in stability analyses of abandoned mines,is challenging due to the dissolution of gypsum when placed in water.To address this problem,we investigated the following methods to saturate gypsum cores taking into account the solubility of gypsum:(1)water immersion,(2)vacuum saturation,and(3)improved vacuum saturation.The research indicates that all the three methods are acceptable but they should be conducted using a saturated gypsum-water solution to minimize dissolution.Further,the research found that the improved vacuum saturation method saturated the test samples within 24 h,while duration of 30 h was required for the other two methods. 展开更多
关键词 Gypsum-hemihydrate-anhydrite transformation DEHYDRATION Rock core SATURATION Moisture content HELIUM PYCNOMETER
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BS22号科钻井提高岩芯基线长度技术 预览
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作者 肖长城 贾中芳 《西部探矿工程》 CAS 2019年第1期77-79,86共4页
算井子地段花岗岩深部环境钻探工程属于国家科研项目,项目要求钻孔所取岩芯必须严丝合缝可拼合,并在岩芯上画基线,目的层孔段单条岩芯基线长度不能低于50m,岩芯在任何位置有磨损导致岩芯无法拼合则基线断。传统地质岩芯钻探对岩芯采取... 算井子地段花岗岩深部环境钻探工程属于国家科研项目,项目要求钻孔所取岩芯必须严丝合缝可拼合,并在岩芯上画基线,目的层孔段单条岩芯基线长度不能低于50m,岩芯在任何位置有磨损导致岩芯无法拼合则基线断。传统地质岩芯钻探对岩芯采取率有相应要求,对岩芯有几处磨损并无严格要求,因此传统钻探施工技术不适用于该项目。必须在传统地质岩芯钻探施工技术的基础上,对钻探施工工艺进行改进,以满足该科研项目对岩芯基线长度的要求。通过对近年来施工该项目的经验总结,从设备、操作技术等方面着手进行了技术改进,现场总结出了一套适用的技术方案。BS22号井目的层404.340~606.755m孔段岩芯的平均基线长度为67.472m,最长基线长度达到了111.505m,解决了施工该项目的钻探技术难题。 展开更多
关键词 花岗岩 岩芯 拼合性 基线长度 清水介质 岩粉
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Chip Flood (vs) Core Flood——Assessment of Flowback and Oil Productivity in Oil-Wet Hydraulic Fractured Rocks 预览
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作者 Srikanth Tangirala James J. Sheng Jiawei Tu 《长江油气(英文版)》 2019年第1期59-78,共20页
New developments in lab technologies help us to explore problems that were less understood in the past due to the limitations and technological constraints. One such problem of assessing the formation damage created b... New developments in lab technologies help us to explore problems that were less understood in the past due to the limitations and technological constraints. One such problem of assessing the formation damage created by the invasion of fracture fluid into the matrix at lab scale is the visualization of fluid saturation distributions inside the matrix. According to the current understanding, the high capillarity contrast between the fracture and the matrix creates a non-uniform saturation distribution of invaded fluid phase during flowback, with the saturations mostly concentrated at the fracture face. With the advent of microfluidics, their application has become more feasible to visually analyze the effectiveness of surfactants to mitigate the invasion-created formation damage and understand the impact of depth of invasion on the characteristics of flowback and oil productivity. Through our previous work, we have successfully demonstrated the capability of this new visualization tool in studying the factors of the presence of surfactant in the fracture fluid and its depth of invasion, to understand the flowback efficiencies and later oil productivities in oil-wet fractured formations. Since the substrate for flooding was a proxy model of an actual rock, the chip flooding results need to be validated with conventional core flooding experiments. In contemporary times, when the new advancements in technology are driving the research progress in all industries, it is mandatory to take a well informed decision by imposing a comparative check on the results with accessible conventional means, wherever possible. The success of validation of chip flooding approach with the core flooding approach in this work instates a strong belief over the application of microfluidics to pursue more research in related fields of oil recovery. 展开更多
关键词 CHIP FLOODING CORE FLOODING Flowback Fracture SURFACTANT
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水溶蜡型芯在精密铸造中的应用
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作者 谭培松 《特种铸造及有色合金》 CAS 北大核心 2019年第1期57-59,共3页
针对内腔结构比较复杂、模具无法抽芯的产品,采用水溶蜡代替尿素制作可溶性型芯进行蜡模制作。水溶蜡可溶性型芯具有外表光滑、强度高,收缩小,尺寸稳定、无气味、环保等特点,能够满足内腔结构复杂产品的制作要求。
关键词 水溶蜡 型芯 精密铸造
Stabilizing silica nan oparticles in high saline water by using polyvinylpyrrolidone for reduction of asphaltene precipitation damage under dynamic condition
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作者 Mohammad Reza Aghajanzadeh Mohammad Sharifi 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1021-1029,共9页
In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this ... In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nan oparticles in differe nt range of water salinity (0-100000 mg-L_1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared w让h the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved. 展开更多
关键词 Formation DAMAGE Enhanced oil recovery SALINITY ASPHALTENE Core FLOODING Nano particles
Genetic diversity and population structure analysis of Capsicum germplasm accessions 预览
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作者 GU Xiao-zhen CAO Ya-cong +6 位作者 ZHANG Zheng-hai ZHANG Bao-xi ZHAO Hong ZHANG Xiao-min WANG Hai-ping LI Xi-xiang WANG Li-hao 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1312-1320,共9页
Genetic diversity plays an essential role in plant breeding and utilization.Pepper is an important vegetable and spice crop worldwide.The genetic diversity of 1 904 accessions of pepper conserved at the National Mid-t... Genetic diversity plays an essential role in plant breeding and utilization.Pepper is an important vegetable and spice crop worldwide.The genetic diversity of 1 904 accessions of pepper conserved at the National Mid-term Genebank for Vegetables,Beijing,China was analyzed based on 29 simple sequence repeat(SSR)markers,which were evenly distributed over 12 pepper chromosomes.The pepper accessions were divided into two groups in a genetic structure analysis,and the two groups showed obvious differences in fruit type and geographical distribution.We finally selected 248 accessions capturing 75.6%of the SSR alleles as the core collection for further research.Insights into the genetic structure of pepper provide the basis for population-level gene mining and genetic improvement. 展开更多
关键词 CAPSICUM GERMPLASM SSR GENETIC DIVERSITY core collection
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论把握高校思想政治理论课“有力支撑”的三个维度
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作者 陈锡喜 刘伟 《马克思主义理论学科研究》 CSSCI 2019年第2期23-33,共11页
把握好习近平提出的中国特色社会主义理论和实践发展新境界的开辟,为思想政治理论课建设提供了"有力支撑"的论断,需要有前提、核心和路径三个维度。前提是认识思想政治理论课的本质和功能,即其本质属性是意识形态课,其功能是... 把握好习近平提出的中国特色社会主义理论和实践发展新境界的开辟,为思想政治理论课建设提供了"有力支撑"的论断,需要有前提、核心和路径三个维度。前提是认识思想政治理论课的本质和功能,即其本质属性是意识形态课,其功能是通过理论教育而达到政治认同。核心是突出中国特色社会主义理论和实践发展的新境界,即要彰显科学社会主义理论逻辑和中国社会发展历史逻辑的统一,凸显中国特色社会主义的历史坐标和世界坐标的交叉,展现对民族复兴和世界文明发展价值的意义。路径是强化科学的理论思维能力和正确的价值判断能力的培养,以使学生把"四个自信"奠定在自觉的基础上。 展开更多
关键词 思想政治理论课 有力支撑 前提 核心 路径
坚持和加强党的全面领导:习近平关于党的建设重要论述的核心内涵 预览
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作者 张志明 《治理现代化研究》 2019年第1期11-14,共4页
习近平关于坚持和加强党的全面领导的重要论述,将党的领导地位提到前所未有高度,内涵极其丰富、思想极为深刻,代表着当代政党领导的最高境界,是习近平关于党的建设重要论述的核心内涵,是中国化马克思主义党建学说发展的最新成果,是习近... 习近平关于坚持和加强党的全面领导的重要论述,将党的领导地位提到前所未有高度,内涵极其丰富、思想极为深刻,代表着当代政党领导的最高境界,是习近平关于党的建设重要论述的核心内涵,是中国化马克思主义党建学说发展的最新成果,是习近平新时代中国特色社会主义思想的重要组成部分。坚持和加强党的全面领导,就要从过去不够全面、不够集中统一、不够有力的领导,走向全面的、高度集中统一的、坚强有力的领导;就要善于在宪法和法律的范围内,运用一切制度安排和领导资源去实现党对国家和社会的高效控制和强力影响;就要厚植党执政的政治基础,不断增强党的政治领导力、思想引领力、群众组织力、社会号召力,确保我们党永葆旺盛生命力和强大战斗力。 展开更多
关键词 习近平 党的建设 全面领导 核心 内涵
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课堂教学民主的内核、结构及其实践张力 预览
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作者 姜丽华 《现代教育科学》 2019年第3期96-99,105共5页
课堂教学民主是教育民主在实践中的一种具体体现,也是当前教育教学改革所推崇的重要价值主张。然而,在力图体现多样的民主的中小学教学实践中,却或多或少地存在着对课堂教学民主误读、误用的现象,从而导致教学民主实践流于形式或走向放... 课堂教学民主是教育民主在实践中的一种具体体现,也是当前教育教学改革所推崇的重要价值主张。然而,在力图体现多样的民主的中小学教学实践中,却或多或少地存在着对课堂教学民主误读、误用的现象,从而导致教学民主实践流于形式或走向放任。基于此,有必要澄清课堂教学民主的合理内核及其特殊性,并对教学民主在实践中如何保持有效的张力进行剖析。 展开更多
关键词 课堂教学民主 内核 结构 张力
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低熔点合金在微波器件电铸中的应用
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作者 李武科 叶贤强 阎宏涛 《模具工业》 2019年第4期59-61,共3页
介绍了低熔点合金在微波器件电铸中的应用,论述了其成型原理与制造方法,给出了该技术的应用实例,低熔点合金型芯克服了铝合金型芯制作周期长、经济成本高等缺点,此方法应用于实际生产取得了良好效果,可以供同行参考。
关键词 电铸 低熔点合金 微波器件 型芯 工艺
活性污泥深部调剖技术的研究与应用 预览
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作者 孙倩茹 《环保科技》 2019年第1期20-23,共4页
针对油田含油污泥日益增多,外排造成环境污染的问题,研制出以污泥、悬浮剂、改性剂为主剂的活性污泥调剖剂。室内实验表明当污泥固相颗粒含量在10%左右时,岩心封堵率可达94%。现场进行8口井试验,平均注水压力提高3.5MPa,累计增油4757吨... 针对油田含油污泥日益增多,外排造成环境污染的问题,研制出以污泥、悬浮剂、改性剂为主剂的活性污泥调剖剂。室内实验表明当污泥固相颗粒含量在10%左右时,岩心封堵率可达94%。现场进行8口井试验,平均注水压力提高3.5MPa,累计增油4757吨。活性污泥深部调剖技术为含油污泥的资源化利用提供了有效途径。 展开更多
关键词 活性污泥 调剖剂 封堵 岩芯
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双轮铣核心液压系统研究 预览
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作者 李青寅 《液压气动与密封》 2019年第7期30-32,共3页
以双轮铣核心液压系统为基础,分析了设备液压系统的原理设计,基本组成部件,以及在设计过程中的创新。
关键词 双轮铣 液压系统 研究 核心
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相山铀矿田西部深钻岩心成像光谱编录及蚀变分带特征 预览
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作者 张川 叶发旺 +1 位作者 徐清俊 邱骏挺 《国土资源遥感》 CSCD 北大核心 2019年第2期231-239,共9页
相山盆地西部是目前相山铀矿田攻深找盲的重要潜力区域,其深部具体的蚀变分带仍有待进一步的研究。成像光谱岩心扫描技术为揭示深部蚀变信息提供了一种新的手段。通过对相山西部牛头山地区的科学深钻进行岩心成像光谱扫描和数据处理,完... 相山盆地西部是目前相山铀矿田攻深找盲的重要潜力区域,其深部具体的蚀变分带仍有待进一步的研究。成像光谱岩心扫描技术为揭示深部蚀变信息提供了一种新的手段。通过对相山西部牛头山地区的科学深钻进行岩心成像光谱扫描和数据处理,完成了5类蚀变矿物的岩心填图,采用像元分类统计算法获得了整个钻孔的蚀变矿物相对含量编录曲线。通过与地质岩性编录和物探测井曲线的对比,印证了岩心成像光谱编录蚀变信息的可靠性。根据深钻岩心成像光谱编录结果,基底以上可划分为3个蚀变带:上--绿泥石化为主,中--高岭石+地开石化和伊利石(主要是短波伊利石)化为主,下--伊利石(长波伊利石多、短波伊利石少)化为主。钻孔上、下2段铀矿化具有明显不同的蚀变矿物组合特征,反映不同波长伊利石的形成环境具有相对差异性。短波伊利石形成于相对偏酸性的流体环境,与酸性蚀变主导的铀成矿密切相关,长波伊利石形成于相对偏碱性的流体环境,与铀成矿的相关性不高。深钻蚀变分带特征反映了偏酸性的流体活动晚于偏碱性的流体活动,并作用于后者之上,铀伴随着后期的钾交代和偏酸性的流体活动逐渐富集;深部碱交代作用的演化具有钠交代→钾交代→酸交代的总体演化规律。 展开更多
关键词 相山 深钻 岩心 成像光谱 蚀变矿物 铀矿化
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Structural Insights into Substrate Selectivity, Catalytic Mechanism,and Redox Regulation of Rice Photosystem Ⅱ Core Phosphatase
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作者 Xiuying Liu Jingchao Chai +2 位作者 Xiaomin Ou Mei Li Zhenfeng Liu 《分子植物:英文版》 SCIE CAS CSCD 2019年第1期86-98,共13页
Photosystem Ⅱ (PSII)core phosphatase (PBCP)selectively dephosphorylates PSII core proteins including D1,D2,CP43,and PsbH.PBCP function is required for efficient degradation of the D1 protein in the repair cycle of PS... Photosystem Ⅱ (PSII)core phosphatase (PBCP)selectively dephosphorylates PSII core proteins including D1,D2,CP43,and PsbH.PBCP function is required for efficient degradation of the D1 protein in the repair cycle of PSII,a supramolecular machinery highly susceptible to photodamage during oxygenic photosynthesis.Here we present structural and functional studies of PBCP from Oryza sativa (OsPBCP).In a symmetrical homodimer of OsPBCP,each monomer contains a PP2C-type phosphatase core domain,a large motif characteristic of PBCPs,and two Small motifs around the active site.The large motif contributes to the formation of a substrate-binding surface groove,and is crucial for the selectivity of PBCP toward PSII core proteins and against the light-harvesting proteins.Remarkably,the phosphatase activity of OsPBCP is strongly inhibited by glutathione and H202.S-Glutathionylation of cysteine residues may introduce steric hindrance and allosteric effects to the active site.Collectively,these results provide detailed mechanistic insights into the substrate selectivity,redox regulation,and catalytic mechanism of PBCP. 展开更多
关键词 PSII CORE PHOSPHATASE structure SUBSTRATE SELECTIVITY redox regulation PSII repair cycle
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