检索结果-南通市图书馆

Petrology of Spinel-Lherzolite Xenoliths from Mazéléand Others Northen Xenoliths Localities of Cameroon Volcanic Line: Exchange Reactions and Equilibrium State

引用

Open Journal of Geology 2024年第5期14卷 629-653页

作者： Nguihdama Dagwai Kamgang Pierre Mbowou Gbambié Isaac Bertrand Chazot Gilles Ngounouno Ismaïla Department of Life and Earth Sciences Higher Teachers&#8217 Training College University of Maroua Maroua Cameroon Department of Earth Sciences Faculty of Science University of Yaound&#233 1 Yaound&#233 Cameroon Department of Mineral Prospecting and Exploration Technologies School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Ocean Geosciences laboratory European University Institute of the Sea (IUEM) Brest France

The alkaline volcanism of the Cameroon Volcanic Line in its northern domain has raised many fresh enclaves of peridotites. The samples selected come from five (05) different localities (Liri, in the plateau of Kapsiki, Mazélé in the NE of Ngaoundéré, Tello and Ganguiré in the se of Ngaoundéré and Likok, locality located in the west of Ngaoundé). The peridotite enclaves of the above localities show restricted mineralogical variation. Most are four-phase spinel-lherzolites, indicating that this is the main lithology that forms the lithospheric mantle below the shallow zone. No traces of garnet or primary plagioclase were detected, which strongly limits the depth range from which the rock fragments were sampled. The textures and the wide equilibrium temperatures (884˚C - 1115˚C) indicate also entrainment of lherzolite xenoliths from shallow depths within the lithosphere and the presence of mantle diapirism. The exchange reactions and equilibrium state established in this work make it possible to characterize the chemical composition of the upper mantle of each region and test the equilibrium state of the phases between them. Variations of major oxides and incompatible elemental concentrations in clinopyroxene indicate a primary control by partial melting. The absence of typical “metasomatic” minerals, low equilibration temperatures and enriched LREE patterns indicate that the upper mantle below septentrional crust of Cameroun underwent an event of cryptic metasomatic enrichment prior to partial melting. The distinctive chemical features, LREE enrichment, strong U, Ce and Pr, depletion relative to Ba, Nb, la, Pb, and T, fractionation of Zr and Hf and therefore ligh high Zr/Hf ratio, low la/Yb, Nb/la and Ti/Eu are all results of interaction of refractory peridotite residues with carbonatite melts.

关键词： Xenoliths Upper Mantle Northern Region Adamawa Cameroon Volcanic Line Exchange Reaction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Local Plants Potentially Suitable for Phytoremediation of Soils Polluted by Heavy Metals: The Case of landfill Sites

引用

Journal of Geoscience and Environment Protection 2024年第7期12卷 72-88页

作者： Kpan Kpan Kouakou Gains Touré Mamadou Ouattara Nouffou Doudjo Kouassi Kouadio Claude Ehouman N’guetta Moïse Ouattara Djibril Tiho seydou UFR Sciences de la Nature Universit Nangui Abrogoua Abidjan Cte dIvoire UFR Agroforesterie Universit Jean Lorougnon Gud Daloa Cte dIvoire

landfills are contaminated sites that need to be cleaned up to prevent human and environmental exposure to pollutants. This article aims to identify local plants capable of restoring soil polluted by heavy metals. To this end, plant species at the Bonoua landfill were inventoried. X-ray fluorescence spectrometry was used to determine the heavy metal content of soil and plants from the landfill. The bioconcentration factor (BCF) of metals in plants was evaluated. The Bonoua landfill is covered with 62 plant species, comprising 28 botanical families and 50 genera. The BCF varied from 0.08 (titanium) to 2.27 (strontium) for Phyllanthus amarus;from 0.06 (titanium) to 1.83 (copper) for Alternanthera sessilis and from 0.03 (arsenic) to 2.10 (strontium) for Amaranthus spinosus. Phyllanthus amarus, Alternanthera sessilis, and Amaranthus spinosus are strontium-accumulating species (BCF > 1). Similarly, copper BCF values were above 1 for Phyllanthus amarus, and Alternanthera sessilis. These two plant species are therefore copper accumulators. In short, Phyllanthus amarus, Alternanthera sessilis, and Amaranthus spinosus are candidate species for phytoremediation of heavy metal-polluted soils, given their BCF > 1.

关键词： Heavy Metals Phytoremediation Phyllanthus amarus Alternanthera sessilis Amaranthus spinosus

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

1976-2016年普若岗日冰川和流域湖泊变化及其对气候变化的响应

引用

气象与环境科学 2024年第2期47卷 54-61页

作者：拉巴拉巴卓玛边多拉珍西藏高原大气环境科学研究所拉萨850001 西藏自治区气候中心拉萨850001

基于藏北地区普若岗日冰川1976-2016年多时相landsat系列卫星影像数据,以及气温、降水量数据,采用ARCGIS空间分析、线性趋势分析、相关分析等方法,研究了普若岗日冰川和流域湖泊面积变化及其对气候变化的响应。结果表明:近41年普若岗日... 详细信息

基于藏北地区普若岗日冰川1976-2016年多时相landsat系列卫星影像数据,以及气温、降水量数据,采用ARCGIS空间分析、线性趋势分析、相关分析等方法,研究了普若岗日冰川和流域湖泊面积变化及其对气候变化的响应。结果表明:近41年普若岗日冰川面积呈显著退缩趋势,41年内冰川面积减少了52.32 km^(2),减小率为12.01%;冰川西北部退缩最为严重,冰川面积减少了12.29 km^(2),减小率为15.77%;且冰川西北部、北部、东部和东南部末端消融显著;其他区域也有不同程度的退缩。流域湖泊面积呈显著增长趋势,共增长了27.17 km^(2),增长率为22.22%;流域气温总体上呈显著增加趋势,平均每10年增加0.48℃;降水量呈不显著上升趋势,平均每10年增加15 mm。降水对冰川和流域湖泊面积影响较小,温度的持续升高是冰川和流域湖泊变化的主要因素。

关键词：普若岗日冰川湖泊面积气候变化

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

STUDOJ PRI KlaSIFIKADO DE CINAJ MEKOPTEROJ

引用

Entomotaxonomia 1981年第1期 19-22页

作者： Chou io Ran Ruibi Wang Sumei (la Nordokcidenta Kolegio de Agrikulturo)

la tutaj specioj de mekopteroj estas karnoman(?)aj, ili kaptas (?)iam tentredojn, tineojn, cikadelojn, miridojn ktp. Je natura balancado en arbara regiono ili estas pli gravaj ol mantoj, libeloj kaj reduvioj. En (?)inio trovi(?)as du familioj de mekopteroj: 1. Panorpidae, plejparto el la specioj vivas en arbaroj, kaj ili flugas ne malproksime tamen vigle aktivas en multatavole kovritaj miksitaj arbaroj. Ili restas kaj ser(?)as man(?)a(?)ojn sur folioj de arbedoj a(?) arbustoj kaj sin ka(?)as nur dum pluvado. Nur malmultaj specioj sin trovas en pli vastaj herbejoj. 2. Bittacidae, la specioj vivas krom en arbaroj anka(?) en herbaroj apud kampoj.

关键词： Wang STUDOJ PRI KlaSIFIKADO DE CINAJ MEKOPTEROJ PRI la DE

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Unexpected complication during extracorporeal membrane oxygenation support: Ventilator associated systemic air embolism

引用

World Journal of Clinical Cases 2018年第9期6卷 274-278页

作者： se-Min Ryu Sung-Min Park Department of Thoracic and Cardiovascular Surgery Kangwon National University Hospital School of Medicine Kangwon National Univerity

Systemic air embolism through a bronchovenous fistu-la(BVF) has been described in patients undergoing positive-pressure ventilation. However, no report has mentioned the potential risks of systemic air embolism through a BVF in patients undergoing extracorporeal membrane oxygenation(ECMO). Positive-pressure ventilation and ECMO support in patients with lung injury can increase the risk of systemic air embolism through a BVF. Increased alveolar pressure, decreased pulmonary venous pressure, and anticoagulation are thought to be the factors that contribute to this complication. Here, we present a case of systemic air embolism in a patient with ECMO and mechanical ventilator support.

关键词： Air embolism Extracorporeal membrane oxygenation Cerebral embolism Positive-pressure ventilation Cardio-pulmonary resuscitation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

POLYMERIZATioN AND CHARACTERIZATioN OF HIGH CONDUCTIVITY AND GOOD ADHENSioN POLYPYRROLE FILMS FOR ELECTROMAGNETIC INTERFERENCE SHIELDING

引用

Chinese Journal of Polymer Science 2010年第6期28卷 923-930页

作者： Yong-sheng Qiao la-zhen Shen Tao Dou Ming Hu Institute of Special Chemicals Taiyuan University of Technology Taiyuan 030024 China School of Chemistry and Chemical Engineering Shanxi Datong University Datong 037009 China School of Electronic Information Engineering Tianjin University Tianjin 300072 China

Polypyrrole（PPy） shows a favorable application in the electromagnetic interference（EMI） shielding due to its good electrical conductivity and outstanding air *** PPy films with high conductivity and good adhesion were successfully polymerized on the surface of insulating epoxy resin substrates using chemical *** factors affecting the properties of PPy films,such as the surface morphology,adhesion between PPy film and substrate,electrical conductivity,EMI shielding effectiveness（se）,were *** adhesion was improved significantly through a three-step surface pretreatment of epoxy resin substrates including removing impurities,roughening,and surface modification with silane coupling *** enhancement in the conductivity of PPy films of about one order of magnitude was achieved by adding dopant in FeCl_3 *** higher the conductivity,the better the shielding *** sodium p-toluenesulfonate doped PPy film as example,EMI se was in the practically useful range of about 30 dB over a wide frequency range from 30 MHz to 1500 *** PPy film samples were characterized by scanning electron microscopy （seM）,infrared spectra（IR）,X-ray photoelectron spectroscopy（XPS） and the flange coaxial transmission *** fourpoint probe method was used to measure conductivity of PPy films.

关键词： Polypyrrole film EMI Conductivity Adhesion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Identifying the ground state structures of point defects in solids

引用

npj Computational Materials 2023年第1期9卷 2095-2105页

作者： Irea Mosquera-Lois seán R.Kavanagh Aron Walsh David O.Scanlon Thomas Young Centre and Department of Chemistry University College London20 Gordon StreetLondon WC1H 0AJUK Thomas Young Centre and Department of Materials Imperial College LondonExhibition RoadLondon SW72AZUK

Point defects are a universal feature of *** identification is addressed by combining experimental measurements with theoretical *** standard modelling approach is,however,prone to missing the ground state atomic configurations associated with energy-lowering reconstructions from the idealised crystallographic *** ground states compromise the accuracy of calculated *** address this issue,we report an approach to navigate the defect configurational landscape using targeted bond distortions and *** of our workflow to eight materials(CdTe,GaAs,Sb_(2)S_(3),Sb_(2)se_(3),CeO_(2),In_(2)O_(3),ZnO,anatase-Tio_(2))reveals symmetry breaking in each host crystal that is not found via conventional local minimisation *** point defect distortions are classified by the associated physico-chemical *** demonstrate the impact of these defect distortions on derived properties,including formation energies,concentrations and charge transition *** work presents a step forward for quantitative modelling of imperfect solids.

关键词： ground distortion solids

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

VORTOJ POR la ELDONO DE la BULTENO

引用

昆虫分类学报 1979年第1期 3-4页

作者： Chou io Lu Chia-sheng (Cefredaktoro) (Vicredaktoro)

'se oni volas entrepreni esploradon de naturo, oni devas etrepreni unue gianklasifikadon kaj scii la diferencajn nomojn.'Ekde la komenco de la nova longa marso por efektivigi la kvar modernigojnen nia lando, la esploraj laboroj de faunaj studoj de insektoj, biologia kontrolo kajinsekta ekologio jam vaste disvolvigas tra la tuta lando. la enketo de biologiaj

关键词： POR VORTOJ POR la ELDONO DE la BULTENO DE

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

STUDO DE JAPIGEDOJ (Ⅴ)(Dipluroj: Japigedoj)

引用

Entomotaxonomia 1983年第4期 339-341页

作者： Chou io Chen Tong(Nordokcidenta Kolegio de Agrikulturo)

En 1966, unu el la a?toroj publikis la artikolojn "Studies on Japydae (Insecta: Diplura)Ⅰ-Ⅲ" kaj "Stidies on Japygidae(Insecta: Diplura) IV" en la Revuo "ACTA ZOOTAXONOMICA SINICA" Vol. Ⅲ, No. 1:51-64 kaj No. 2:115-119 (kun pl. Ⅰ-Ⅳ). En tiuj artikoloj la a?toro resumis la mondan situacion de studoj pri Japigedoj, pridiskutis pri la metodoj de klasifikado kaj priskribis 4 ?inajn speciojn de Parajapigenoj studinte la morfologion de Occasjapyx japonicus (Enderlein). En tiu ?i artikolo la a?toroj priskribis 8 ?inajn genrojn kaj 14 speciojn de subfamilio Japigenoj, el kiuj 2 genroj kaj 6 specioj estas novaj por scienco, kaj 2 genroj kaj 1

关键词： STUDO DE JAPIGEDOJ la Dipluroj DE

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

la SISTEM ATIKO KAJ FILOGENio DE la GENRO SINOPHORA MELICHAR (Homopteroj:Afroforedoj)

引用

Entomotaxonomia 1986年第Z1期 116-119页

作者： Chou io Yuan Feng Liang Aiping(Nordokcidenta Agrikultura Universitato)

5 specioj apartenantaj al 2 subgenroj t. e. Sinophora s. str. kaj Sinaphrade la genro Sinophora estis priskribitaj antaue (L. Malichar 1902, Z. *** kaj G. Horton 1934, S. Matsmura 1942, G. A. Anufriev 1972), elkiuj 4 estis raportitaj et Cinio. En tiu ci artikolo la autoroj pliigas 8 speciojnel Cinio novajn por scienco (Sichuan, Yunnan, Xizang, Shaanxi, Hubei). lacefaj temoj diskutital en detalo en la cina teksto en tiu ci artikolo estas resu-mataj jene.

关键词： la Homopteroj la SISTEM ATIKO KAJ FILOGENio DE la GENRO SINOPHORA MELICHAR DE

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：