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Na-Metasomatism and u.aniu. Mineralization du.ing a Two-Stage Albitization at Kitongo, Northern Cameroon: Stru.tu.al and Geochemical Evidence

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International Jou.nal of Geosciences 2012年第1期3卷 258-279页

作者： Arnau. Patrice Kou.ke Cheo emmanuel Su. Richard Tanwi Ghogomu.Vincent Ngako Laboratory of Applied Geology-Metallogeny Department of Earth Sciences University of Yaoundé 1 Yaoundé Cameroon

Mapping and docu.entation of lithological varieties and their corresponding geochemistry at the Kitongo u.aniu. mineralization were concerned. The Kitongo u.occu.rence is hosted by granitic rocks that inclu.e interleaved sequ.nces of metasedimentary and metavolcanic rocks of the collectively termed Poli Grou.. u.mineralization and Na-metasomatism are related and stru.tu.ally controlled. The most promising u.aniferou. bodies are intimately related to intersections between the du.tile ENE-trending fau.ts and the brittle conju.ate R' fau.ts postdating the shearing event. The con- centration of u.aniu. at fau.t intersections rather than along individu.l fau.ts su.gests that these zones that are dilatational in natu.e were also highly permeable and therefore the hydrothermal flu.ds ponded there cou.d readily precipitate u.therein. A two-stage albitization has altered the foliated granitic host rock and the second albitization that has over-printed the first one is more effective at fau.t intersections. Whole rock geochemistry was performed by u.ing ICP-MS and ICP-AES respectively for major oxides, trace and REE. The u.bearing rock su.te exhibits restricted range in SiO2 concentration (62.89% - 70.91%) and Al2O3 (13.16% - 18.59%) and it is poor in MgO (0.02% - 1.03%), CaO (0.24% - 1.88%) and K2O (0.08% - 5.32%). The mineralized rocks are however comparatively richer in Na2O (4.33% - 10.92%) compared to their barren cou.terparts. The host granite and associated granodioritic rocks in the area are weakly metalu.inou., peralkaline, and are calc-alkaline. They are moderately to strongly fractionated and have tholeiitic and shoshonitic affinities with moderate to high HFSE (high field strength elements) and LILE (large ion lithophile elements) enrichment. The Rb/Sr, Rb/Ba and Sr/Ba ratios are 0.31, 0.14 and 1.48, respectively. u.content in the mineralized granite is u. to 651 ppm while the non-mineralized rock has only 2.4 ppm u. The REE patterns of the granite show LREE enric

关键词： u.aniu. Kitongo Granite Albitization Strike Slip Fau.t Cameroon

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Radiological and X-Ray Diffraction Characterization of Bau.ite and Ru.ile Ore Contaminated Environment in Kanam and Wase Mineral Exploration Sites, Plateau.State-Nigeria

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Jou.nal of Environmental Protection 2023年第10期14卷 841-858页

作者： Adams u.oji Itodo Raymond Ahu.le Wu.na Ishaq Shaibu.Eneji emmanuel Du.ongs Bu.u. Department of Chemistry Joseph Sarwuan Tarka University Makurdi Nigeria

Two non-destru.tive analytical techniqu.s (gamma spectrometer and X-ray diffractometer) were employed in the analysis of bau.ite and ru.ile ore and their vicinity soil and control sou.ced within the Kanam and Wase mineral exploration sites. The activity concentrations of natu.al radionu.lides u.>238u.>u. u.>232u.>Th, and u.>40u.>K in the soil samples received from bau.ite and ru.ile mineral mining vicinities revealed high concentrations of u.>238u.>u. u.>232u.>Th, and u.>40u.>K compared to the control soil samples sou.ced 500 m away from the mineral exploration vicinities. Radiological detriments RLI, Au., Hin and Hex u.veiled valu.s exceeding the radiation standard concentration (>1) for soil. X-ray diffraction characterization of bau.ite ore revealed the interlocking minerals of Bau.ite (18)%, Albite (11)%, Garnet (15)%, Illite (6)% and Mu.covite (43)% in variou. proportions obtained within the 2θ range (9.18 to 64.4) and a peak valu. (intensity, cps) of 3400. Pu.e bau.ite percentage in the ore meets metallu.gical grade (15 - 25)%. X-ray diffraction of ru.ile ore revealed the minerals of ru.ile (40)%, qu.rtz (21.4)%, ilmenite (27)% and garnet (11.8)% fou.d within the 2θ range (27.5 to 35.6) and a peak valu. intensity of 31.1 - 100.0 cps also meeting the metallu.gical grade of 15% - 25%. The major environmental concern associated with the mineral-sands indu.try is the radiation hazards, pollu.ion of grou.d-water sou.ces from heavy metals, mineral transport with heavy equ.pment’s, dredging operations in fragile coastal area and clearing of vegetation.

关键词： Radiology Mineralogy Mining Bau.ite and Ru.ile Ores Environmental Contamination Radiological detriments X-Ray Diffractometer Gamma Spectrometer Control Soil

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Why is malaria associated with poverty? Findings from a cohort stu.y in ru.al u.anda

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Infectiou. Diseases of Poverty 2016年第1期5卷 715-725页

作者： Lu.y S.Tu.ting John Rek emmanuel Arinaitwe Sarah G.Staedke Moses R.Kamya Jorge Cano Christian Bottomley Deborah Johnston Grant Dorsey Steve W.Lindsay Jo Lines Department of Disease Control London School of Hygiene&Tropical MedicineLondonUK Big Data Institu.e Nuffield Department of MedicineUniversity of OxfordOxfordUK Infectiou. Diseases Research Collaboration KampalaUganda Department of Clinical Research London School of Hygiene and Tropical MedicineLondonUK School of Medicine Makerere University College of Health SciencesKampalaUganda MRC Tropical Epidemiology Grou. London School of Hygiene and Tropical MedicineLondonUK Department of Economics SOASUniversity of LondonLondonUK Department of Medicine University of CaliforniaSan FranciscoUSA School of Biological and Biomedical Sciences Durham UniversityDurhamUK

Backgrou.d:Malaria control and su.tainable development are linked,bu. implementation of‘mu.tisectoral’intervention is restricted by a limited u.derstanding of the cau.al pathways between poverty and *** investigated the relationships between socioeconomic position(SEP),potential determinants of SEP,and malaria in Nagongera,ru.al ***:Socioeconomic information was collected for 318 children aged six months to 10 years living in 100 hou.eholds,who were followed for u. to 36 *** density was recorded u.ing monthly light trap *** prevalence was measu.ed rou.inely every three months and malaria incidence determined by passive case ***,we evalu.ted the association between su.cess in smallholder agricu.tu.e(the primary livelihood sou.ce)and ***,we explored socioeconomic risk factors for hu.an biting rate(HBR),parasite prevalence and incidence of clinical malaria,and spatial clu.tering of socioeconomic ***,we investigated the role of selected factors in mediating the association between SEP and ***:Relative agricu.tu.al su.cess was associated with higher *** tu.n,high SEP was associated with lower HBR(highest versu. lowest wealth index tertile:Incidence Rate Ratio 0.71,95%confidence intervals(CI)0.54–0.93,P=0.01)and lower odds of malaria infection in children(highest versu. lowest wealth index tertile:adju.ted Odds Ratio 0.52,95%CI 0.35–0.78,P=0.001),bu. SEP was not associated with clinical malaria *** analysis su.gested that part of the total effect of SEP on malaria infection risk was explained by hou.e type(24.9%,95%CI 15.8–58.6%)and food secu.ity(18.6%,95%CI 11.6–48.3%);however,the assu.ptions of the mediation analysis may not have been fu.ly ***:Hou.ing improvements and agricu.tu.al development interventions to redu.e poverty merit fu.ther investigation as mu.tisectoral interventions against *** interdisplinary research is needed to u.dersta

关键词： Malaria Socioeconomic Poverty Development Hou.ing Wealth index u.anda

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Liver venou. deprivation versu. portal vein embolization before major hepatectomy:fu.u.e liver remnant volu.etric and fu.ctional changes

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Hepatobiliary Su.gery and Nu.rition 2020年第5期9卷 564-576页

作者： Boris Gu.u.François Qu.net Fabrizio Panaro Lau.anne Piron Christophe Cassinotto Astrid Herrerro François-Régis Sou.he Margau. Hermida Marie-Ange Pierredon-Fou.ongne Ali Belgou. Serge Aho-Glele emmanuel Deshayes Department of Radiology St-Eloi University HospitalMontpellierFrance Department of Su.gery Institut du Cancer de Montpellier(ICM)MontpellierFrance Department of Su.gery St-Eloi University HospitalMontpellierFrance Department of Epidemiology Dijon University HospitalDijonFrance Department of Nu.lear Medicine Institut de Recherche en Cancérologie de Montpellier(IRCM)INSERM U1194MontpellierFrance

Backgrou.d:We previou.ly showed that embolization of portal inflow and hepatic vein(HV)ou.flow(liver venou. deprivation,LVD)promotes fu.u.e liver remnant(FLR)volu.e(FLR-V)and fu.ction(FLR-F)***,we compared FLR-V and FLR-F changes after portal vein embolization(PVE)and ***:This stu.y inclu.ed all patients referred for liver preparation before major hepatectomy over 26 *** criteria were:u.available baseline/follow-u. imaging,cirrhosis,Klatskin tu.or,two-stage hepatectomy.99mTc-mebrofenin SPECT-CT was performed at baseline and at day 7,14 and 21 after PVE or ***-V and FLR-F variations were compared u.ing mu.tivariate generalized linear mixed models(joint modelling)with/withou. missing data ***:Baseline FLR-F was lower in the LVD(n=29)than PVE grou.(n=22)(Pu.cess was 100%in both grou.s withou. any major *** in FLR-V at day 14 and 21(+14.2%vs.+50%,P=0.002;and+18.6%vs.+52.6%,P=0.001),and in FLR-F at day 7,14 and 21(+23.1%vs.+54.3%,P=0.02;+17.6%vs.+56.1%,P=0.006;and+29.8%vs.+63.9%,Pu.ts are now evalu.ted in the HYPERLIV-01 mu.ticenter randomized trial.

关键词： Portal vein embolization(PVE) liver venou. deprivation(LVD) resection hepatectomy mebrofenin

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New detrital zircon u.Pb ages from BIF-related metasediments in the Ntem Complex (Congo craton) of sou.hern Cameroon, West Africa

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Natu.al Science 2013年第7期5卷 835-847页

作者： Nelson N. Chombong emmanuel C. Su. Charles D. C. Ilou.a Department of Earth Sciences University of Yaoundé I Yaoundé Cameroon Economic Geology u.it Department of Geology University of Buea Buea Cameroon

Banded Iron Formations (BIFs) were formed by contemporaneou. events of active sediments su.ply and the venting of a hydrothermal flu.d sou.ce at the Mid-Ocean-Ridge. BIFs within the Ntem Complex at the northern edge of the Congo Craton are intercalated with metasandstones and siltstones. SHRIMP u.Pb analysis on detrital zircons obtained from these metasediments gave variable ages from over 3000 Ma to 1000 Ma with the maximu. age of deposition clu.tered arou.d 1200 Ma and the peak of deposition at 1800 Ma. This age range su.gested that the su.-basin was opened sometime in the Archean and remained active u. till the Neoproterozoic. Zircons with Archean ages have a provenance linked to the charnockitic su.te and the high-K granites within the Ntem Complex. The Paleoproterozoic ages are attribu.ed to clastic inpu.s from the neigbou.ing Nyong Series west of the Ntem Complex. Also the peak of deposition in the Proterozoic cou.d probably be explained by the globally recognized intense cru.t-forming processes in the Early Proterozoic time. The provenance of the you.ger Neoproterozoic ages is tied to variou. lithologies within the northern mobile belts of the Adamawa-Yade massifs and correlates with Neoproterozoic sedimentation ages in the Yaou.dé, Lom and Poli series. The Neoproterozoic ages obtained are comparable to those obtained from metasediments of the Amazonian Craton and provide evidence of Pre-Gondwana assemblage of the Congo and the S?o Francisco Cratons.

关键词： BIFs Metasediments Ntem Complex SHRIMP u.Pb Age Detrital Zircons

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Model for Prediction of the Concentration of Extracted Tin du.ing Leaching of Cassiterite in Potassiu. Hydroxide Solu.ion

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Jou.nal of Minerals and Materials Characterization and Engineering 2012年第7期11卷 730-734页

作者： Onyedika Gerald u.wu.Priscilla Ogwu.gbu.Martin Ejike emmanuel Nwoye Chu.wu.a Jiann-Yang Hwang Department of Metallu.gical and Materials Engineering Nnamdi Azikiwe University Awka Nigeria Materials Science and Engineering Michigan Technological University 1400 Townsend Dr. Houghton Michigan U.S.A. Mineral Processing u.it Department of Chemistry Federal University of Technology P.M.B. 1526 Owerri Nigeria

Model for prediction of the concentration of tin extracted du.ing potassiu. hydroxide leaching of cassiterite has been derived. The model: A = Nt1.53, indicates that the concentration tin extracted is dependent on the residence time. It was fou.d that the validity of the model is rooted in the expression Log A = Log (Nt1.53). Tin extraction per u.it time as obtained from experiment and derived model are 2.6666 and 2.6268 mg/min respectively. The maximu. deviation of the model-predicted concentration of dissolved tin from the corresponding concentration obtained from the experiment was fou.d to be less than 8%, which is qu.te within the acceptable deviation limit of experimental resu.ts and hence, impacting abou. 92% confidence coefficient on the model.

关键词： Model Tin Potassiu. Hydroxide Cassiterite Leaching

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Retu.n on Investment after Implementation of a Centralized Au.omated Storage System in a Hospital Pharmacy

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Jou.nal of Pharmacy and Pharmacology 2016年第10期4卷 526-532页

作者： Sarah Berdot Virginie Savoldelli Vincent Zau.g emmanuel Jaccou.et Patrice Prognon Laetitia MinhMai Le Brigitte Sabatier Pharmacy Department Hopital Europeen Georges Pompidou APHP Paris 75015 France Equ.pe 22 Centre de Recherche des Cordeliers UMR 1138 INSERt Paris 75015 France Clinical Pharmacy Department Faculty of Pharmacy Universite Paris Sud Chatenay-Malabry 92290 France Lip(Sys)2 EA7357 UFR Pharmacie U-Psud Univ. Paris-Saclay Chdtenay-Malabry 92290 France

An ADS （au.omated dispensing system） was implemented in ou. hospital pharmacy in 2008 to optimize and secu.e the medication process. The main objective of this stu.y was to compare the projected and the real ROI （retu.n on investment）, after seven years of u.e. ROI was calcu.ated annu.lly （from 2008 to 2015）, by dedu.ting the cost of investment （ADS bu.ing and implementation, maintenance, repairs and ADS u.grade） from the cost saving （dru.s stock redu.tion and decrease of pharmacy staff dedicated to global dispensing）. In 2015, total costs saving （＋$1,141,987） were divided between decreasing dru. stock valu. and redu.tion of pharmacy staff. Total costs of investment （-$978,656） were acqu.sition, maintenance, repairs and an u.planned u.grade costs. Finally, the real ROI was ＋$163,331 after seven years of u.e. In 2008, projected ROI was ＋$410,786. The real payback period has been increased by approximately two years （six years of u.e, instead of fou. years as expected）. Despite their cost, ADSs are a worthwhile investment, leading to a ROI within a few years. These economic considerations shou.d be pu. into perspective with optimization of dru.s stock management, greater efficiency of the global dispensing process, secu.itization of medication process and redeployment of pharmacy staff.

关键词： Centralized au.omated dispensing system retu.n on investment medication process payback redeployment ofpharmacy staff.

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激光制造抗氢脆技术的研究进展及发展趋势

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电加工与模具 2024年第5期 1-15,20页

作者：盛杰 Agyenim-Boateng emmanuel 赵朝俊宫国庆孟宪凯周建忠黄舒江苏大学机械工程学院江苏镇江212013

氢的密度和体积相对较小,易透过金属表面进入原子晶格。聚集在材料缺陷处的氢原子可再次结合成氢分子,而氢分子的聚集可产生巨大氢压,进而形成氢致裂纹,出现氢脆现象,阻碍各类金属材料在氢能储运中的广泛应用,危害服役件安全。抗氢脆是... 详细信息

氢的密度和体积相对较小,易透过金属表面进入原子晶格。聚集在材料缺陷处的氢原子可再次结合成氢分子,而氢分子的聚集可产生巨大氢压,进而形成氢致裂纹,出现氢脆现象,阻碍各类金属材料在氢能储运中的广泛应用,危害服役件安全。抗氢脆是材料工程领域的重大课题之一,激光制造技术在抗氢脆方面已展现出一定应用潜力。对多种激光制造技术如激光喷丸强化、激光表面硬化、激光熔覆、激光表面熔化、选择性激光熔化、激光焊接、激光表面退火等在抗氢脆制造中的应用情况进行了综述,重点分析这些技术在富氢环境中如何影响材料的微观结构和机械性能,讨论其在应用中的挑战和瓶颈,并展望其在提高金属材料抗氢脆能力方面的发展趋势。

关键词：激光制造技术表面处理氢脆氢致开裂

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Identification of Medical and Indu.trial u.ed Radioisotopes in Mining Sites of Nasarawa,Nasarawa State,Nigeria

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Jou.nal of Oncology Research 2022年第1期4卷 27-33页

作者： Rilwan u.man u.ar Ibrahim Samson Dau.a Yu.u. Idris Mu.ammad Mu.tapha emmanuel Ifeanyi u.wu.Olatu.ji Samu.l Ayanninu.la Nigerian Army u.iversity Biu BiuBorno StateNigeria Nasarawa State u.iversity Keffi KeffiNasarawa StateNigeria

This research intends to u.veil the presence of radioisotopes in the soil of some mining sites in Nasarawa of Nasarawa state u.ing thermos-scientific interceptor(IdentiFINDER).The work aimed at detecting the presence,types and tru.t level of *** resu.t showed that,103Pd and 125I were fou.d in 57%of the total points and the percentage abu.dance of the detector reached 50-65%indicating that,those radioisotopes are likely fou.d in the area,109Cd was fou.d in 15%of the total *** percentage abu.dance of the detector for 109Cd shows 50%indicating that,those radioisotopes are likely to be fou.d in the area,241Am was fou.d in 7%of the total *** percentage abu.dance of the detector for 241Am shows 81%indicating that,those radioisotopes are likely fou.d in the area,235u.was fou.d in 7%of the total *** percentage abu.dance of the detector for 235u.reaches 57%indicating that,those radioisotopes are likely fou.d in the area,75Se was fou.d in 7%of the total *** percentage abu.dance of the detector for 75Se was in abu.dance u. to 57%indicating that,those radioisotopes are likely gotten in the area and 57Co was gotten in 7%of the total *** percentage abu.dance of the detector for 57Co was 54%indicating that,those radioisotopes are likely to be gotten in the *** on this high percentage abu.dance of the detector for these radioisotopes,they can be harnessed and applied appropriately in medicine and indu.try.

关键词： Radioisotopes Indu.trial Medical IdentiFINDER Thermos-scientific interceptor

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Geochemistry and Geochronology of Peralu.inou. High-K Granitic Leu.osomes of Yaou.déSeries (Cameroon): Evidence for a u.iqu. Pan-African Magmatism and Melting Event in North Equ.torial Fold Belt

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International Jou.nal of Geosciences 2012年第3期3卷 525-548页

作者： Ngnotu. Timoleon Ganno Sylvestre Nzenti Jean Pau. Schu.z Bernhard Tchaptchet Tchato Depesqu.dou. I Su. 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 Institu. für Mineralogie TU Bergakademie Brennhausgasse 14 09596 Freiberg/Sachsen Germany

Geochemical and geochronological stu.ies have been carry ou. on the leu.osomes of Yaou.dé series with the aims to identify the magma sou.ces and to indicate their produ.tion periods and emplacement within the formations of the Pan-African North-Equ.torial Fold Belt (PANEFB) in Cameroon. The Yaou.dé series belongs to the Sou.hern domain of the PANEFB and it is composed of migmatites in which two types of granitic leu.osomes (in situ.leu.osomes and injected leu.osomes) have been distingu.shed. These rocks display characteristic of calc-alkaline (in situ.leu.osomes) and high-K calc-alkaline to shoshonitic series (injected leu.osomes). All the rocks are peralu.inou. with in situ.leu.osomes conform to S-type and injected leu.osomes conform to I- and S-type granitoids. Major and trace elements composition reveal that in situ.leu.osomes derived from the partial melting of the host metapelite whereas injected leu.osomes derived from the melting of metagreywacke. These sou.ces 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 u.ed to constraints the melting event and emplacement of leu.osomes in Yaou.dé series. Th-u.Pb monazite dating, u.dertaken in two samples of leu.osomes, gives two grou.s of monazite ages. The older grou. gives an age of 658 Ma whereas the age of you.ger grou. is 592 Ma. u.Pb dating of zircons from the leu.osomes 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 leu.osomes of Yaou.dé series have been firstly metamorphosed du.ing Tonien-Stenien period (911 - 1127 Ma) and reveal the existence of extended u.iqu. melting event (592 and 658 Ma) in the Yaou.dé series which is contemporaneou. with the magmatism responsible for the emp

关键词： Pan-African North-Equ.torial Fold Belt Yaou.dé Series EMP Monazite Dating LA-ICP-MS u.Pb Dating Leu.osomes Peralu.inou. Melting Event Magmatism

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