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SILLS软件在单个萤石流体包裹体LA-ICP-MS微量元素分析数据处理中的应用 被引量:1
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作者 李阳 邹灏 +2 位作者 刘行 蒋修未 李蝶 《岩矿测试》 CAS CSCD 北大核心 2020年第2期300-310,共11页
近年来激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)应用于单个流体包裹体成分定量分析已成为研究流体包裹体的最佳手段之一。该实验过程和数据处理比较复杂,目前国内外采用的数据分析软件为一款基于MATLAB的SILLS软件,该软件主要是对矿物... 近年来激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)应用于单个流体包裹体成分定量分析已成为研究流体包裹体的最佳手段之一。该实验过程和数据处理比较复杂,目前国内外采用的数据分析软件为一款基于MATLAB的SILLS软件,该软件主要是对矿物(锆石)、流体包裹体以及熔体包裹体LA-ICP-MS分析结果进行处理。本文以萤石流体包裹体LA-ICP-MS分析为例,阐述了样品制备与流体包裹体的优选方法,对流体包裹体片厚度以及单个流体包裹体的选取要求作了详细描述,对仪器参数设置、内外标样选取和剥蚀方法等进行了说明。基于SILLS软件采用尖峰消除的方法对待处理数据进行校正,对不同种类型的波峰进行峰宽的选取。在元素比值校正和等效盐度计算过程中,由于被测样品是萤石,Ca元素具有较高的背景值,选择以Na作为流体包裹体的内标元素,以Ca作为寄主矿物的内标元素对寄主矿物浓度进行计算,同时提出以电价平衡代替质量平衡进行等效盐度计算。以上方案提高了LA-ICP-MS分析单个萤石流体包裹体的准确性,有助于解释成矿流体来源和矿床成因等问题。 展开更多
关键词 LA-ICP-MS 单个流体包裹体 sillS软件 定量分析 数据处理
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Fingered Intrusion of Shallow Saucer-shaped Igneous Sills: Insights from the Jiaojiang Sag, East China Sea 被引量:9
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作者 GUO Rui ZHANG Gongcheng +4 位作者 ZHANG Jinwei ZHAO Xingbin LIU Junbang YUAN Dawei SONG Shuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1306-1318,共13页
An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close ... An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close relationship with CO2 content in nearby gas discoveries. A new observational model, which incorporates simple upward propagation, simple horizontal propagation, and transgressive propagation, was proposed to interpret these sill intrusions. In this model, the source magma of the saucer-shaped sills was injected from their lowest points near the center. The transgressive propagation can be interpreted as a combination of the vertical and horizontal propagation. Most shallow sub-volcanic intrusions in the Jiaojiang sag exhibit fingered characteristics, both vertically and horizontally. The vertical fingered propagation produced saucer-shaped sills arranged in the flower style. Along the brims of lower sills could usually be found the upper sills, which are interpreted to have formed simultaneously with or later than the lower feeder sills. In the second type, the chilled paths of the older sills were reutilized by subsequent intrusions. The horizontal fingered propagation formed sheet intrusions that exhibit groove, lobate, tubular, and crevasse splay- like geometry in plan view. In 3D view, the sheet intrusions have still preserved the lower center and higher rim that similar with the sub-rounded saucer-shaped sills. Although fracture propagation may be important, flow inflation was the key mechanism of magma intrusion. Further consideration of the mechanisms underlying sill formation may help explain the fingered characteristics of sill propagation. 展开更多
关键词 Saucer-shaped sill fingered intrusion feeder relationship lobate sill flow inflation Jiaojiang sag
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SILL语言学习策略量表的信度研究 被引量:1
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作者 徐爽 《贵州教育学院学报》 2008年第4期68-70,共3页
SILL语言学习策略量表在语言学习策略研究中被大量的使用。针对其在中国使用的具体情况对该量袁的信度进行了探索性的研究,以期对SILL语言学习策略量表在中国大学生中的使用提供更为可靠的依据。
关键词 语言学习策略 sill量表 信度
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SILL在少数民族地区初中英语学生中的应用
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作者 孙霞 韦启卫 《英语广场(学术研究)》 2016年第11期138-140,共3页
本文综述国内外学者对学习策略的理解,以Oxford(1990)语言学习测量表(Strategy Inventory for Language Learning)为测量工具,以民族地区某中学初三年级学生为研究对象,探讨了三个问题,即该校初三年级学生使用英语学习策略特征,分析SIL... 本文综述国内外学者对学习策略的理解,以Oxford(1990)语言学习测量表(Strategy Inventory for Language Learning)为测量工具,以民族地区某中学初三年级学生为研究对象,探讨了三个问题,即该校初三年级学生使用英语学习策略特征,分析SILL信度差异及英语学习策略与初三年级英语毕业考试成绩之间的关系。笔者同时提出如何因地制宜地运用学习策略,提高少数民族地区中学英语教学质量的建设性意见。 展开更多
关键词 sill 学习策略特征 信度 关系
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基于SILL的阿拉伯留学生在华英语学习策略实证研究
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作者 刘中阳 Samar Sayed 《教育教学论坛》 2023年第44期30-35,共6页
我国高校阿拉伯留学生的数量不断增加,英语作为其日常学习交流的主要语言,重要性不言而喻。通过Oxford语言学习策略量表(SILL),对阿拉伯留学生英语学习过程中的元认知、认知、社交、补偿、情感、记忆等六个方面策略的使用频率,了解阿拉... 我国高校阿拉伯留学生的数量不断增加,英语作为其日常学习交流的主要语言,重要性不言而喻。通过Oxford语言学习策略量表(SILL),对阿拉伯留学生英语学习过程中的元认知、认知、社交、补偿、情感、记忆等六个方面策略的使用频率,了解阿拉伯留学生在我国这样的非英语国家进行专业课程学习时的英语学习策略,结果发现元认知策略是最常用的策略,而记忆策略很少被主动用到。因此,在英语课堂上,教师可以考虑充分调动学生的积极性,使其日常所用和所学相结合,进一步提升学习效果。 展开更多
关键词 阿拉伯留学生 sill 英语学习策略 中国 EFL
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Petrogenesis of the~2115 Ma Haicheng Mafic Sills in the Eastern North China Craton and Their Implications for An Intra-Continental Rifting 被引量:30
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作者 WANG Xinping PENG Peng +1 位作者 WANG Chong YANG Shuyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期128-,共1页
It is well known that there are widespread igneous events at;100 Ma in the Eastern North China Craton;however,their tectonic environments are controversial.They were thought to be either related to an intra-continenta... It is well known that there are widespread igneous events at;100 Ma in the Eastern North China Craton;however,their tectonic environments are controversial.They were thought to be either related to an intra-continental rifting or 展开更多
关键词 Ma Haicheng Mafic sills in the Eastern North China Craton and Their Implications for An Intra-Continental Rifting Petrogenesis of the
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Numerical investigation of the stresses in backfilled stopes overlying a sill mat 被引量:2
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作者 Mohamed Amine Sobhi Li Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第3期108-119,共12页
Backfill is commonly used in underground mines to help increase the ore recovery rate and reduce the ore dilution. The use of a part of mine waste as underground backfill material also helps reduce the environmental i... Backfill is commonly used in underground mines to help increase the ore recovery rate and reduce the ore dilution. The use of a part of mine waste as underground backfill material also helps reduce the environmental impact of mining operations. After all, backfill is used to provide a working platform or safer working space. Its primary and most important role is to improve the rock mass stability around mine openings. However, most available solutions to stress analyses were developed for an isolated stope, without taking into account the influence of mine depth, or of adjacent stopes. In this paper,results from a numerical study carried out to evaluate the stresses in backfilled stopes overlying a sill mat are presented. Mine depth and excavation of the underlying stope below the sill mat(horizontal pillar)are both taken into consideration. The influence of stope geometry, backfill, sill mat and rock properties on the stresses is also evaluated. Compared with the case of a single isolated backfilled stope, the numerical results show that the stress magnitudes in the overlying backfill are considerably increased due to the excavation of the underlying stope. In general, the stresses also increase with mine depth and backfill stiffness, while these tend to decrease with an increase in the surrounding rock mass stiffness.These results suggest that existing solutions for backfill design may need to be revised. 展开更多
关键词 Mine depth Backfill sill mat Stresses Numerical modeling
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Early Eocene leucocratic sill/dike swarms in the Gangdese belt, southern Tibet: Tectonic implications for Indo-Asian collision 被引量:7
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作者 Xu-xuan Ma Li-E Gao +2 位作者 Zhong-bao Zhao Xi-jie Chen Hai-bing Li 《China Geology》 2021年第1期56-66,共11页
The timing of the initial Indo-Asian collision is a subject of debate for a long time.Besides,the magmatic trace of the collisional process is also unclear.In the present study,the authors report Early Eocene leucocra... The timing of the initial Indo-Asian collision is a subject of debate for a long time.Besides,the magmatic trace of the collisional process is also unclear.In the present study,the authors report Early Eocene leucocratic sill/dike swarms in the northern edge of the Nymo intrusive complex of the Gangdese belt,southern Tibet.The Nymo intrusive complex was emplaced at ca.50–47 Ma and surrounded by the metamorphosed Jurassic-aged Bima Formation volcano-sedimentary sequence along its northern side.At outcrops,the leucocratic sills/dikes intruded along or truncated the deformed foliations of the host Bima Formation,which has been subject to high-temperature amphibolite-facies metamorphism at ca.50–47 Ma.Detailed cathodoluminescence image analyses reveal that the zircon grains of the leucocratic sills/dikes have core-mantle textures.The cores yield the Jurassic ages comparable to the protolith ages of the Bima Formation.In contrast,the mantles of zircon grains yield weighted mean ages of ca.49–47 Ma,representing the crystallization timing of these leucocratic sills/dikes.The coeval ages for the Nymo intrusive complex,the high-temperature metamorphism,and the leucocratic sills/dikes indicate that a close relationship exists among them.The authors tentatively suggest that these leucocratic sills/dikes were generated from partial melting of the Jurassic-aged Bima Formation volcanic rocks,triggered by the high heat from the magma chamber of the Nymo intrusive complex.This Early Eocene tectono-thermal event of coeval magmatism,metamorphism and partial melting was most likely formed during the Indo-Asian collisional setting. 展开更多
关键词 Leucocratic sill/dike swarm Early Eocene Indo-Asian collision GANGDESE Tibet China
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Strategic sill pillar design for reduced hanging wall overbreak in longhole mining 被引量:2
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作者 Tuo Chen Hani S.Mitri 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期975-982,共8页
Steeply dipping,vein and tabular orebodies are traditionally extracted with longitudinal retreat mining methods such as Eureka and Avoca in a bottom-up sequence with delayed backfill.To increase productivity,sill pill... Steeply dipping,vein and tabular orebodies are traditionally extracted with longitudinal retreat mining methods such as Eureka and Avoca in a bottom-up sequence with delayed backfill.To increase productivity,sill pillars in the orebody are used to separate mining zones thus allowing production to take place simultaneously in two or more zones.While such mining methods are productive,they may be accompanied with high volumes of hanging wall overbreak causing significant unplanned ore dilution.In this work,it is shown through a mine design case study of a narrow vein deposit that a sill pillar could also play a significant role in limiting hanging wall overbreak.To demonstrate the role of sill pillar,a novel numerical modelling scheme is proposed to account for progressive stope wall overbreak.A numerical modelling approach of element death and rebirth is developed to allow for the detected stope overbreak to be immediately removed and replaced with backfill material before upper-level stope extraction.It is further shown that the average overbreak volume could be reduced by as much as 33%when the sill pillar is strategically placed in the lower half of a mine plan. 展开更多
关键词 Underground mine design Longitudinal mining sill pillar design Unplanned ore dilution Numerical modelling
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Geochemistry and petrology of rift-related mafic sills and arc-related Gabbro–Diorite bodies, Northern Bafq District,Central Iran 被引量:1
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作者 S.M.Niktabar N.Rashidnejad Omran 《Acta Geochimica》 EI CAS CSCD 2018年第2期180-192,共13页
Two types of mafic intrusions have been recognized in the north of the Bafq district, Central Iran. A number of olivine-gabbroic to gabbroic sills intruded the Rizu Formation, comprised of alternating carbonate and vo... Two types of mafic intrusions have been recognized in the north of the Bafq district, Central Iran. A number of olivine-gabbroic to gabbroic sills intruded the Rizu Formation, comprised of alternating carbonate and volcanic rocks. Mineralogical data show that olivine + pyroxene +brown amphibole(kaersutite) + calcic plagioclase +opaque comprise the olivine-gabbroic rocks, and intermediate(or sodic) plagioclase + altered pyroxene and altered amphibole to biotite + opaque minerals the gabbroic rocks.Both rock types have shown within-plate and alkaline characters and have been presumed to be related to rift formation. The mafic-alkaline magma source of the sills is proposed to have been derived from enriched mantle.Regionally, two Gabbro–Diorite intrusions have been identified in the metamorphic complexes. Mineralogical data suggest that the pyroxene + amphibole(hornblende) +plagioclase + biotite + opaque minerals formed the gabbro to diorite intrusions. These rocks have shown characteristics of calc-alkaline and volcanic arc magmatism. 展开更多
关键词 sillS Rizu formation RIFT Volcanic arc
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Characteristics of a Drainage Channel with Staggered Indented Sills for Controlling Debris Flows 被引量:4
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作者 CHEN Xiao-qing YOU Yong +2 位作者 CHEN Jian-gang HUANG Kai LI De-ji 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1242-1252,共11页
The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, wherea... The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, whereas the fluid near the sidewall had a stop-start movement pattern; the viscous debris flow exhibited a stable structure between the indented sills. The experimental results indicate that the mean velocity of the debris flow increased with increasing channel gradients, and the debris flow velocity was slightly affected by the angle of the sills. The average velocity of the non-viscous debris flow increased in the range of(0.5–1.5) interval between the indented sills, whereas the average velocity of the viscous debris flow increased initially and then decreased in the range of(0.75–1.25) interval between the indented sills. The depth of the non-viscous debris flow tended to gradually increase as the channel gradients increased, whereas the depth of the viscous debris flow gradually decreased as the channel gradients increased. When the discharge of the debris flow was constant, the angle and the interval between the indented sills had a slight effect on the depth of the viscous debris flow, whereas the depth of the non-viscous debris flow exhibited a different trend, as the sill angles and intervals were varied. 展开更多
关键词 Debris flow Drainage channel Staggered indented sill Wenchuan earthquake
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Bar in SILL Questionnaire for Multiple Results Processing: Users' Frequency and Confidence 被引量:1
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作者 Penelope Kambakis-Vougiouklis 《Sino-US English Teaching》 2013年第3期184-199,共16页
One hundred and fifteen first-year students of Greek took the SILL (Strategy Inventory for Language Learning) questionnaire in an attempt to reveal and activate potential a successful and widely used questionnaire l... One hundred and fifteen first-year students of Greek took the SILL (Strategy Inventory for Language Learning) questionnaire in an attempt to reveal and activate potential a successful and widely used questionnaire like SILL might have but not identified and investigated so far. The first original point to be investigated, tackled in a previous experiment (Kambakis-Vougiouklis, 2012), concerns users' confidence whether their choice of a specific strategy is effective while the second point concerns the use of the bar as an alternative statistical tool. More specifically, in this particular experiment the bar is not divided only into five equal length spaces as in the first experiment but also into five equal area spaces according to Gauss distribution, giving the researcher the chance to investigate possible differences between two ways of data processing--an advantage only the use of the bar could provide in the analysis stage. Additionally, there are advantages concerning results collection, as subjects and researcher will have a completely free choice among infinite points on a line rather than a limited 3, 4, 5, and 6 of a Likert scale, avoiding at the same time fine verbal differences between different subdivisions. Although the two different methods of processing performed homogeneous behaviour with not statistically considerable differences, it needs further applications in order to reach safe conclusions 展开更多
关键词 sill (Strategy Inventory for Language Learning) BAR CONFIDENCE Gauss distribution
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Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout Sill(Zenaga inlier,Anti-Atlas,Morocco)
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作者 Abdelhak AIT LAHNA Colombo Celso Gaeta TASSINARI +9 位作者 Nasrrddine YOUBI Hassan ADMOU Joao MATA El Hafid BOUOUGRI Latifa CHAIB Richard E.ERNST Ulf SODERLUND Moulay Ahmed BOUMEHDI Mohamed Khalil BENSALAH El Mostapha AARAB 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期1-,共1页
The Anti-Atlas belt of southern Morocco is situated on the northern edge of the West African craton(WAC).It corresponds to a broad anticlinorium some 800 km long and 200 km wide,trending ENE-WSW,parallel to the
关键词 Pb Zenaga inlier Morocco Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout sill ANTI-ATLAS
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Controlling entry in soft rock with natural support strength,strikesill,etc.
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作者 王有俊 赵庆彪 孙利中 《Journal of Coal Science & Engineering(China)》 2008年第2期186-189,共4页
Presented the concept of the natural support strength.The natural support strength,the strike sill,the multifunction retractors (developed by the author) and etc.were used with the technical measures to change the pas... Presented the concept of the natural support strength.The natural support strength,the strike sill,the multifunction retractors (developed by the author) and etc.were used with the technical measures to change the passive support to the initiative support, and the soft rock entry was supported.And its process is simple and less equipment is needed,and the cost is low and the advance rate is high,which can meet the require- ments of actual mining.It solves many support difficult problems. 展开更多
关键词 natural support strength strike sill multifunction retractor soft rock entry
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The Timing of the Palaeoproterozoic Great Oxidation Event using Dykes,Sills and Bolcanics of the Ongeluk Large Igneous Province,Kaapvaal Craton
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作者 Ashley P.GUMSLEY Kevin R.CHAMBERLAIN +5 位作者 Wouter BLEEKER Ulf SODERLUND Michiel O.DE KOCK Tobias C.KAMPMANN Emilie R.LARSSON Andrey BEKKER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期67-68,共2页
The Neoarchaean to Palaeoproterozoic Transvaal Supergroup of the Kaapvaal Craton,southern Africa,is one of the best-preserved and most complete stratigraphic records across a critical in juncture in the Earth’s history.
关键词 sills and Bolcanics of the Ongeluk Large Igneous Province The Timing of the Palaeoproterozoic Great Oxidation Event using Dykes GOE
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Petrography and Mineral Chemistry of Metamorphogenic Magnetite in the Layered Sill of the JC Pura Schist Belt, Karnataka, India
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作者 B. G. Dayanand S. Santhosh B. C. Prabhakar 《International Journal of Geosciences》 2024年第12期1020-1037,共18页
JC Pura schist belt has gained scope recently with reports of nickel, magnetite, PGEs, and traces of gold. The layered sill in the schist belt is a linear patch of ultramafic sequences (peridotite and pyroxenite) with... JC Pura schist belt has gained scope recently with reports of nickel, magnetite, PGEs, and traces of gold. The layered sill in the schist belt is a linear patch of ultramafic sequences (peridotite and pyroxenite) with metamorphogenic magnetite mineralization. The metamorphogenic magnetite appears as interbands in layered sequences and as veins in serpentinite. The present study focuses on understanding the characteristics of metamorphogenic magnetite by petrographic and EPMA analysis. The study found that the precursor chromite grains are transformed into Cr-magnetite and magnetite in the spinel transformation system due to metamorphism and hydrothermal alteration. The Cr, Mg, Al, and Ni are depleted during transformation, and Fe is enriched. The Cr-magnetite appears homogenous in the vein due to serpentinization, indicating prograde greenschist to amphibolite facies metamorphism, and the area has suffered an episodic metamorphic process. The results of Cr-magnetite cation proportions of Cr fall within ishkulite variety data range of 0.10 - 0.50 apfu (atoms per formula unit). Cr-magnetite variety Ishkulite represents an additional miscibility gap in the Cr-Fe3+ transformation series other than ferrite chromite and chrome magnetite. The transformation process primarily involves the oxidation of chromium and the reduction of iron. The oxidation of chromite by highly oxidizing fluids with increasing pressure and temperature alters to Cr-magnetite, where chromium in the +3 state oxidizes to the +6 state, forming soluble chromate ions and diffusing with Fe3+. Then, it transforms into magnetite due to reducing conditions. Cr-magnetite vein indicates the potential for chromite deposits in the area, and hydrothermal altered magnetites could be a source for hosting valuable precious metals like gold and PGEs. Further investigations are needed to assess the mineralization potential and its extent. 展开更多
关键词 JC Pura Layered sill Metamorphogenic Magnetite Cr-Magnetite Ishkulite
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基于SILL的国内大学生学习策略与英语成绩相关的元分析 被引量:11
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作者 李文 张军 《外语教学理论与实践》 CSSCI 北大核心 2018年第4期39-47,共9页
本研究旨在探讨基于Oxford's (1990) Strategy Inventory for Language Learning (SILL)的国内大学生学习策略与英语成绩的相关,并探讨影响二者关系的研究特征的调节作用。通过文献检索,纳入文献41篇,产生48个独立研究样本,总样本量... 本研究旨在探讨基于Oxford's (1990) Strategy Inventory for Language Learning (SILL)的国内大学生学习策略与英语成绩的相关,并探讨影响二者关系的研究特征的调节作用。通过文献检索,纳入文献41篇,产生48个独立研究样本,总样本量为8689。结果表明,大学生学习策略与英语成绩呈从小到中等程度的显著正相关。记忆策略、情感策略与英语成绩的相关受被试类型、考核方式的调节作用;学习策略与英语成绩的相关不受出版类型的影响。 展开更多
关键词 英语学习策略 英语成绩 sill 元分析
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Diabase Sills in the Outer Zone of the Emeishan Large Igneous Province, Southwest China: Petrogenesis and Tectonic Implications 被引量:2
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作者 Yong Huang Chuan He +1 位作者 Neng-Song Chen Bin Xia 《Journal of Earth Science》 SCIE CAS CSCD 2019年第4期739-753,共15页
Compositionally and texturally zoned diabase dykes and sills occur in the outer zone of the Emeishan large igneous province(ELIP) in the southern Guizhou Province,Southwest China. Based on the detailed petrology,whole... Compositionally and texturally zoned diabase dykes and sills occur in the outer zone of the Emeishan large igneous province(ELIP) in the southern Guizhou Province,Southwest China. Based on the detailed petrology,whole rock geochemistry,zircon U-Pb geochronology and Hf isotopes and clinopyroxene mineral compositions studies,we investigate a representative diabase sill in the Luodian region with a view to understanding its petrogenesis and tectonic implications. Formed as composite zoned sub-volcanic intrusion,the diabase sill is characterized by gabbros and diabases in the inner zone and amygdaloidal diabases sporadically in the chilled zone within the upper sill margin. The diabasic and gabbroic rocks are composed of quartz-free and quartz-bearing groups. The quartz-free group rocks have low Si O2(45.7 wt.%–49.5 wt.%),moderate Mg O(5.66 wt.%–7.88 wt.%),high Ti O2(2.54 wt.%–3.65 wt.%),and Ti/Y values(536–747),corresponding to high-Ti type rocks. The quartz-bearing group rocks have higher Si O2(49.8 wt.%–51.7 wt.%) and lower Mg O(4.23 wt.%–4.74 wt.%),higher Ti O2(3.16 wt.%–3.63 wt.%),but lower Ti/Y values(399–419) than the quartz-free group ones,and thus belong to the low-Ti type. Both groups of rocks are enriched in LREE and LILE with negative Nb-Ta anomalies,and show broad tholeiitic affinity. The precursor magma of the high-Ti rocks might have originated from a source composed of mantle plume and subcontinental lithosphere mantle components,with minor crustal contamination during ascending. The magma of the low-Ti rocks was produced by mingling of the high-Ti diabasic rocks with minor injected intermediate-acidic magma plugs or blebs,suggesting magma mingling as one of the effective ways to change the high-Ti to low-Ti rocks of the ELIP. The diabasic sill underwent a rapid cooling event probably in response to a rapid tectonic uplift event,which probably occurred in the waning stage of ELIP during transition between the Middle and Late Permian after the domal uplift induced by the mantle-plume or in the Late Jurassic. 展开更多
关键词 DIABASE sill high-Ti and low-Ti rocks PETROGENESIS tectonic evolution EMEISHAN large IGNEOUS province(ELIP) Guizhou
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REDUCTION OF STILLING BASIN LENGTH WITH TALL END SILL 被引量:2
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作者 FATHI-MOGHADAM Manoochehr HAGHIGHIPOUR Sadegh +1 位作者 LASHKAR-ARA Babak AGHTOUMAN Peyman 《Journal of Hydrodynamics》 SCIE EI CSCD 2011年第4期498-502,共5页
Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction. The case with a single tall sill was simulated ... Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction. The case with a single tall sill was simulated in a horizontal flume downstream of a sluice gate. Results of experiments are compared with the classical hydraulic jump, and significant effect of tall sill on dissipation of energy in shorter distance was confirmed. Furthermore, the generated jumps were classified based on the ratio of sill height to basin length, and a simple design criterion was proposed to estimate the basin length for a desired jump and particular inflow. 展开更多
关键词 forced hydraulic jump energy dissipater sill stilling basin length
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The hydraulic characteristics of end-dump closure with the assistance of backwater-sill in diversion channel 被引量:1
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作者 陆贺 胡志根 +3 位作者 刘全 吕国轩 叶建群 任金明 《Journal of Hydrodynamics》 SCIE EI CSCD 2016年第5期886-896,共11页
The river closure is a key step in the water dam construction, and the end-dump closure is a general way to cut offthe river flow. The hydraulic characteristics at the closure gap are the main factors which affect the... The river closure is a key step in the water dam construction, and the end-dump closure is a general way to cut offthe river flow. The hydraulic characteristics at the closure gap are the main factors which affect the extent of closure difficulty. A method is proposed to reduce the difficulty of diversion channel closure by pre-building a closure structure called the backwater-sill at the downstream toe of the closure gap to change the flow pattern at the closure gap. The results of the physical model test and the three- dimensional numerical simulation indicate that the backwater-sill has the effects of raising the water level at the downstream toe of the closure gap, decreasing the water surface gradient, and reducing the closure drop and the flow velocity at the closure gap. The schemes with different dike widths, different closure gap widths, and different backwater-sill widths and heights are simulated. The results show that the height of the backwater-sill is the key factor affecting the hydro-indicators at the closure gap, while the influe- nce of the dike width, the closure gap width or the backwater-sill width can be ignored. The higher the backwater-sill is, the lower the hydro-indicators will be. Based on the numerical simulations and the physical model tests on the hydraulic characteristics at the closure gap of the backwater-sill assisted closure, the hydro-indicators and its calculation method are proposed to provide a theoreti- cal support for the river closure. 展开更多
关键词 diversion channel closure closure structure end-dump closure backwater-sill hydraulic characteristics
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