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Geochemistry and Geochronology of Peraluminous High-K Granitic Leucosomes of YaoundéSeries (Cameroon): Evidence for a Unique Pan-African Magmatism and Melting Event in North Equatorial fold Belt

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International Journal of Geosciences 2012年第3期3卷 525-548页

作者： Ngnotue Timoleon Ganno Sylvestre Nzenti Jean Paul Schulz bernhard Tchaptchet Tchato Depesquidoux I Suh Cheo Emmanuel Department of Earth Sciences University of Yaoundé I P.O. Box. 3412 Messa-Yaoundé Department of Geology University of Buea P.O. Box. 63 Buea-Cameroon Department of Geology University of Dschang P.O. Box. 67 Dschang-Cameroon Institut für Mineralogie TU Bergakademie Brennhausgasse 14 09596 Freiberg/Sachsen Germany

Geochemical and geochronological studies have been carry out on the leucosomes of Yaoundé series with the aims to identify the magma sources and to indicate their production periods and emplacement within the formations of the Pan-African North-Equatorial fold Belt (PANEfB) in Cameroon. The Yaoundé series belongs to the Southern domain of the PANEfB and it is composed of migmatites in which two types of granitic leucosomes (in situ leucosomes and injected leucosomes) have been distinguished. These rocks display characteristic of calc-alkaline (in situ leucosomes) and high-K calc-alkaline to shoshonitic series (injected leucosomes). All the rocks are peraluminous with in situ leucosomes conform to S-type and injected leucosomes conform to I- and S-type granitoids. Major and trace elements composition reveal that in situ leucosomes derived from the partial melting of the host metapelite whereas injected leucosomes derived from the melting of metagreywacke. These sources are similar to those of granitoids from central and northern domains of the PANEfB. Th-U-Pb dating by electron microprobe (EMP) and LA-ICP-MS U-Pb dating on zircon have been used to constraints the melting event and emplacement of leucosomes in Yaoundé series. Th-U-Pb monazite dating, undertaken in two samples of leucosomes, gives two groups of monazite ages. The older group gives an age of 658 Ma whereas the age of younger group is 592 Ma. U-Pb dating of zircons from the leucosomes reveals a Pan-African age ranging from 626 to 654 Ma whereas zircons from metapelitic host rock reveal the overprinting of an early Pan-African event 911 - 1127 Ma on Palaeoproterozoic (2127 Ma) inheritance. These data clearly indicate that the host rocks of leucosomes of Yaoundé series have been firstly metamorphosed during Tonien-Stenien period (911 - 1127 Ma) and reveal the existence of extended unique melting event (592 and 658 Ma) in the Yaoundé series which is contemporaneous with the magmatism responsible for the emp

关键词： Pan-African North-Equatorial fold Belt Yaoundé Series EMP Monazite Dating LA-ICP-MS U-Pb Dating Leucosomes Peraluminous Melting Event Magmatism

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Thermodynamic Aspects of Nanostructured CoAl Intermetallic Compound during Mechanical Alloying

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Journal of Materials Science & Technology 2011年第7期27卷 601-606页

作者： S.N. Hosseini T. Mousavi f. Karimzadeh M.H. Enayati Department of Materials Engineering Nanotechnology and Advanced Materials Institute Isfahan University of Technology84156-83111 Iran

The nanostructured CoAl intermetallic compound was produced by mechanical alloying （MA） of the Co50Al50 elemental powder mixture in a planetary high energy ball mill. The ordered B2-CoAl structure with the grain size of about 6 nm was formed via a gradual reaction after 10 h of MA. A thermodynamic analysis of the process was also done. The results showed that the intermetallic compound of CoAl had the minimum gibbs free energy compared to solid solution and amorphous states indicating the initial MA product was the most stable phase in the Co-Al system which was changed to a partially disordered structure with a steady long-range order of 0.82 at further milling. This amount of disordering caused the enthalpy of final product to show an increase of about 5.1 kJ·mol-1. Calculation of enthalpy related to the triple defect formation revealed that the enthalpy required for Al anti-sites formation was about 3 times greater than that for Co anti-sites formation.

关键词： Intermetallics CoAl Nanostructured materials Mechanical alloying Thermodynamics

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THE CALCULATION Of BaO ACTIVITIES IN BaO-Baf_2-Cr_2O_3 SYSTEM fLUXES USING SCHUHMANN METHOD

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 911-916页

作者： L.f. Li Z.P. Chen, M.f. Jiang and W.Z. Wang(Department of ferrous Metallurgy, School of Materials and Motallurgy, Northeastern University Shenyang 110006, China)(The Technology Center, Baoshan Iron & Steel Complex, Shanghai 201900, China) Northeastern Univ Shenyang China

The principle and steps for the calculation of component activities in fluxes using Schuhmann method are described. On the foris of gibbs-Duhem equation and using Cr2O3 activities in BaO-Baf2-Cr2O3 system fiuxes, BaO activities at 1523 and 1673K are calculated, respectivelg,and the isoactivity diagrums of BaO are also obtained. The calculation results indicate that BaO activity increases with increasing its content in fiuxes, and decreaaes with the increase of Cr2O3 content at a given XBaO/XBaf2 ratio.

关键词： Shuhmann method fluxes activity gibbs-Duhem equation

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Changes in nectar supply： A possible cause of widespread butterfly decline

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Current Zoology 2012年第3期58卷 384-391页

作者： Michiel f. WALLISDEVRIES Chris A.M. Van SWAAY Calijn L. PLATE De Vlinderstichting / Dutch Butterfly Conservation EO. Box 506 6700 AM Wageningen The Netherlands Wageningen University Lab of Entomology EO. Box 8031 6700 EH Wageningen The Netherlands Statistics Netherlands （CBS） P.O. Box 24500 2490 HA The Hague The Netherlands

Recent studies have documented declining trends of various groups of flower-visiting insects, even common butterfly species. Causes of these declines are still unclear but the loss of habitat quality across the wider countryside is thought to be a major factor. Nectar supply constitutes one of the main resources determining habitat quality. Yet, data on changes in nectar abundance are lacking. In this study, we provide the first analysis of changes in floral nectar abundance on a national scale and link these data to trends in butterfly species richness and abundance. We used transect data from the Dutch Butterfly Monitoring Scheme to compare two time periods: 1994-1995 and 2007-2008. The results show that butterfly decline can indeed be linked to a substantial decline in overall flower abundance and specific nectar plants, such as thistles. The decline is as severe in reported flower generalists as in flower specialists. We suggest that eutrophication is a main cause of the decline of nectar sources.

关键词：蝴蝶花蜜原因供应栖息地质量水体富营养化蜜源植物物种丰富度

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面对向可持续发展挑战的广告业

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产业与环境 2003年第3期25卷 88-91页

作者： bernhard Adriaensens 刘云清 Professeur de Marketing Université de Bruxelles et Administrateur-Délégué de la Fédération Mondiale des Annonceurs1120 Avenue Louise 1050 Bruxelles Belgique

某些公司使用基于消费者现有和潜在需求的市场开发和公关战略.另外一些公司则希望制造一个新的世界,提前应对这些趋势并启动新的举措.选择最有勇气路径的企业形成了汇总在下面的几条规则,这反映了他们对可持续发展标准的赞同.

关键词：可持续发展广告业企业市场开发消费

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New Semiconductor Thin-film Microcavity Surface Emiters

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电子显微学报 1997年第4期 11-14页

作者： R.X.Jin 1\ D.Boggayarapu 2\ M.S.Tobin 1\ R.P.Leavitt 1 H.M.gibbs 3\ G.Khitrova 3\ f.Jahnke 4\ S.W.Koch 4 ( 1 Photonics Branch,Physics Division,AMSRL PS PB,Army Research Laboratory,2800 Powder Mill Road,Adelphi,MD 20783,USA) ( 2 Depar

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ＮｅｗＳｅｍｉｃｏｎｄｕｃｔｏｒＴｈｉｎＦｉｌｍＭｉｃｒｏｃａｖｉｔｙＳｕｒｆａｃｅＥｍｉｔｅｒｓＲ．Ｘ．Ｊｉｎ１Ｄ．Ｂｏｇｇａｙａｒａｐｕ２Ｍ．Ｓ．Ｔｏｂｉｎ１Ｒ．Ｐ．Ｌｅａｖｉｔ１Ｈ．Ｍ．Ｇｉｂｂｓ３Ｇ．Ｋｈｉｔｒｏｖａ３Ｆ．Ｊａｈｎｋｅ４Ｓ．...

关键词： Thin-film Semiconductor Surface New Emiters Microcavity

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Positive predictors for gastroesophageal reflux disease and the therapeutic response to proton-pump inhibitors

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World Journal of Gastroenterology 2014年第14期20卷 4017-4024页

作者： Valentin Becker Stefan Grotz Christoph Schlag Simon Nennstiel Analena Beitz bernhard Haller Roland M Schmid Alexander Meining Monther Bajbouj Ⅱ. Medizinische Klinik und Poliklinik Technische Universit?t München Institut für Medizinische Statistik und Epidemiologie Technische Universit?t München

AIM:To identify objective and subjective predictors for the reliable diagnosis of gastroesophageal reflux disease(GERD)and the response to proton pump inhibitor(PPI)***:Retrospectively,683 consecutive patients suspected for GERD who underwent pH-metry/impedance measurement(pH/MII)were *** patients had previously undergone standard PPI treatment(e.g.,pantoprazole 40 mg/d or comparable).four hundred sixty patients were at least 10 d off PPIs(group A),whereas 223 patients were analyzed during their ongoing PPI therapy(group B).In addition,all patients completed a standardized symptom-and lifestyle-based questionnaire,including the therapeutic response to previous PPI trials on a 10-point *** multivariance analyses were performed to identify criteria associated with positive therapeutic response to ***:In group A,positive predictors(PPs)for response in empirical PPI trials were typical GERD symptoms(heartburn and regurgitation),a positive symptom index(SI)and pathological results in pH/MII,along with atypical symptoms,including hoarseness and *** group B,regular alcohol consumption was associated with the therapeutic *** PPs for pathological results in pH/MII in group A included positive SI,male gender,obesity,heartburn and *** group B,the PPs were positive SI and *** for positive SI,the PPs were pathological pH and/or MII,heartburn regurgitation,fullness,nausea and vomiting in group A and pathological pH and/or MII in group ***:Anamnestic parameters(gender,obesity,alcohol)can predict PPI *** non-obese,female patients with non-typical reflux symptoms,pH/MII should be considered instead of empirical PPIs.

关键词： Gastroesophageal reflux Gastroesophageal reflux di

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低功率染料热光学双稳性

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中国激光 1983年第Z1期 464-465页

作者：李淳飞张雷 M.C.Roshford H.M.gibbs 哈尔滨工业大学物理系哈尔滨工业大学物理系美国亚利桑那大学光学科学中心美国亚利桑那大学光学科学中心

将若丹明或隐花菁染料置于法布里-珀罗干涉仪中,并以激光入射获得了光学双稳性。不同的溶剂、浓度和腔长具有不同的阈值功率和开关时间,还观察了反射光双稳性、连续功率运转、热漂移现象、不稳定输出效应、交扰效应(crosstalk)和光学多... 详细信息

将若丹明或隐花菁染料置于法布里-珀罗干涉仪中,并以激光入射获得了光学双稳性。不同的溶剂、浓度和腔长具有不同的阈值功率和开关时间,还观察了反射光双稳性、连续功率运转、热漂移现象、不稳定输出效应、交扰效应(crosstalk)和光学多稳态现象。作者认为此种光学双稳性起因于激光的热效应。激光加热介质和光腔,使折射率和腔长发生变化从而导致相移变化 (1)式中α为反射膜层的线膨胀系数。设干涉仪的精细度为f,实现双稳运转的相移变化至少为Δφ=2π/f,则由(1)式可求出相应的温升ΔT。而产生此温升的单位面积热能密度为

关键词：激光功率密度双稳开关时间腔长染料染剂干涉仪测量仪器

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速败制胜

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作者： (美)伯恩哈德·施罗德(bernhard Schroeder)

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世界上最伟大的销售员

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作者： (美)乔·吉拉德(Joe Girard) (美)托尼·吉布斯(Tony gibbs)

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