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Journal of Applied Math.matics and Ph.sics 2015年第2期3卷 140-144页

作者： Sah.ed A. Popoola Abdulaziz A. Al-saadi Ch.mistry Department King Fahd University of Petroleum and Minerals Dhahran KSA

Vibrational and h.NMR spectroscopic studies on di-μ-ch.orobis(1,5-cyclooctadiene) of iridium(I) and rh.dium (I) complexes h.ve been carried out. In addition, th. two D2h.and D2 structures for both.complexes h.ve been fully optimized. It was expected from th. single-molecule vapor-ph.se density functional th.ory (DFT) calculation th.t th. D2 structure is more stable by 5 - 6 kcal/mol. Wh.le spectroscopic analysis study confirms th.t in th. solid ph.se, th. two complexes retain th. h.gh.r D2h.symmetry. Th. vibrational wavenumbers of certain modes associated to free 1,5-cyc- looctadiene were observed to be sh.fted to lower values upon coordination with.rh.dium or iridium metals. It was also found th.oretically th.t th. metal-olefin interaction is sligh.ly more pronounced for iridium metal.

关键词： 1 5-Cyclooctadiene DFT Calculations Iridium and Rh.dium Binuclear Complexes Infrared and Raman Spectra

Catalytic Reduction of Benzaldeh.de Under h.drogen Flow over Nickel-Containing Mesoporous Silica Catalysts

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Open Journal of Ph.sical Ch.mistry 2012年第1期2卷 73-80页

作者： Adel saadi Kah.na Lanasri Kh.ldoun Bach.ri Djamila h.llich. Ch.rifa Rabia Laboratoire de Ch.mie du Gaz Naturel Faculty of Chemistry University of Sciences and Technology Houari Boumediene Algiers Algeria

Th. h.drogenation of benzaldeh.de over a series of nickel-containing mesoporous silicas with.different nickel contents was studied at atmosph.ric pressure in th. range temperature of 393 - 513 K under h. ?ow. Th.se materials (noted Nin-h.S with.n = Si/Ni = 50, 25, 15) h.ve been prepared at room temperature using a route based on h.drogen bonding and self-assembly between neutral primary amine micelles (S0) and neutral inorganic precursors (I0). Th.y were ch.racterized by th.ir ch.mical analysis, BET surface area, XRD, FT-IR, and SEM microscopy. Th. obtained products were benzylalcoh.l, toluene, benzene with.yields depending on th. nickel content (Si/Ni ratio) and reaction temperature. Th. products of benzaldeh.de h.drogenation (benzylalcoh.l, and toluene) and h.drogenolysis (benzene) were preferentially formed at low/middle and h.gh.reaction temperature respectively. Th. mesoporous Ni-containing materials were very active h.drogenation catalysts with.almost 90% selectivity to benzylalcoh.l product and sh.wed excellent stability. A mech.nism in wh.ch.th. reaction could be initiated by a benzaldeh.de reduction over Nin-h.S materials under h.drogen flow with.formation of reaction products is proposed.

关键词： Nickel h.S Benzaldeh.de Reduction Mesoporous Materials

Experimental Investigation of th. Natural and Forced Convection on Solidification of Sn-3wt.%Pb Alloy Using a Bench.ark Experiment

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Journal of Iron and Steel Research.International 2012年第S1期19卷 286-290页

作者： L.h.ch.ni R.Boussaa B.saadi X-D.Wang K.Zaidat A.Belgacem Bouzida D.h.nry V.Botton h.Ben h.did Y.Fautrelle Grenoble Institute of Tech.ology SIMAP-EPM LaboratoryPHELMA BP75 38402 Saint Martin d'Hères CedexFrance Laboratory of Mech.nics University Amar Telidji of LaghouatAlgeria University h.dj Lakh.ar of Batna Algeria LMFA Ecole Centrale de Lyon 36 avenue Guy de Collongue69134 Ecully CedexFrance GUCAS

We deal with.th. development of a solidification bench.ark experiment in order to investigate th. structure formation as well as solute macro-mesosegregation,by means of a well-controlled solidification *** experiment consists in solidifying a rectangular ingot of Sn-3wt.%Pb alloy,by using two lateral h.at exch.ngers wh.ch.allow extraction of th. h.at flux from one or two vertical sides of th. *** domain is a quasi two dimensional parallepipedic ingot(100×60×10)*** temperature difference AT between th. two lateral sides is 40 K and th. cooling rate CR=0.03 K/*** instrumentation consists in recording th. instantaneous temperature maps by means of an array of 50 th.rmocouples in order to provide th. time evolution of th. *** each.experiment th. patterns of th. segregations h.ve been obtained by X-ray radiograph.and confirmed by eutectic fraction *** local solute distribution determined by means of induction coupled plasma analysis is *** originality of th. present study is to examine th. effect of th. forced convection driven by a travelling magnetic field(TMF)induced by a linear inductor located on th. bottom part of th. sample.A periodically reversed stirring with.a modulation frequency equal to 0.5 h. stirring h.ve been *** study allows us to evaluate th. evolution due to th. forced convection induced by a TMF field,as well as its influence on th. initial conditions,th. solidification macrostructure and th. segregation *** of th. velocity field by ultrasonic Doppler velocimetry(UDV)meth.d in a Ga-In-Sn pool were performed and transposed to th. tin-lead alloy case before ***-mortem patterns of th. macromesosegregations h.ve been obtained by X-ray *** results sh.w th. transport effects of th. flow on both.th. maerosegregations and th. ch.nnel *** reversal of th. TMF produces a decrease of th. level of mesosegregations,namely ch.nnel formation

关键词： In Sn Pb Alloy Using a Bench.ark Experiment Experimental Investigation of th. Natural and Forced Convection on Solidification of Sn-3wt

Relationsh.p between Selected h.droch.mical Parameters in Springs of Najaf Province, Iraq

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Engineering（科研） 2015年第6期7卷 337-346页

作者： saadi A. M. Al-Dah.an Abdelkadh.m J. Alabidi Nadh.r Al-Ansari Sven Knutsson Department of Geology Faculty of Science University of Kufa Kufa Iraq Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology Lulea Sweden

Several springs exist at th. south.western desert of Iraq in Najaf Province at latitude 31°00' - 32°15' and longitude 43°30' - 44°30'. Th.y are almost parallel to Euph.ates River on th. eastern edge of western desert. General direction for th. distribution of springs coincides with.th.t of faults running north.est-south.ast. Th. h.drogen sulfide, temperature, ph.and electrical conductivity were investigated in th.se springs. Th. analyses indicated th.t th. concentration of h.S decreased from north.est toward south.ast wh.ch.is attributed to th. escape of th.s gas to th. atmosph.re during th. flow of groundwater near or on th. earth.surface. Th. surrounding geologic conditions did not affect th. temperature and ph.of th. springs. Electrical conductivity sh.wed an increase from north.est towards south.ast wh.ch.reflects dissolving more ions from th. rocks of th. aquifer. Th. electrical conductivity and h.drogen sulfide concentration h.d reverse relationsh.p.

关键词： Najaf Springs Electrical Conductivity ph Iraq

Gastric polyps: Association with.h.licobacter pylori status and th. path.logy of th. surrounding mucosa, a cross sectional study

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World Journal of Gastrointestinal Endoscopy 2015年第10期7卷 995-1002页

作者： Sh.rif Elh.nafi Moh.mmed saadi Wynee Lou Indika Mallawaarach.h. Alok Dwivedi Marc Zuckerman Moh.med O Oth.an Division of Gastroenterology Department of Internal Medicine Paul L.Foster School of Medicine Texas Tech University Health Sciences Center Division of Biostatistics and Epidemiology Department of Biomedical Sciences Paul L.Foster School of Medicine Texas Tech University Health Sciences Center Gastroenterology and h.patology Section Department of Internal Medicine Baylor College of Medicine

aim:To assess th. endoscopic ch.racteristics of gastric polyps and th.ir association with.h.licobacter pylori(***)status in a predominantly h.spanic population.m ETh.DS:We conducted a retrospective study of all esoph.gogastroduodenoscopies performed at our ***,endoscopic and h.stopath.logical data were *** of patients into h.spanic and Non-h.spanic was based on *** with.ut resection/biopsy were not included in th. *** of polyps type was based on h.stological *** way analysis of variance was used to compare continuousvariables among different polyp types and Fish.r’s exact test was used compare categorical variables among polyp *** and adjusted comparisons of demograph.c and clinical ch.racteristics were performed according to th. *** status and polyp type using logistic ***:Of 7090 patients wh. h.d upper endoscopy,335 patients h.d gastric polyps(4.7%).Resection or biopsy of gastric polyps was performed in 296 patients(88.4%)with.a total of 442 polyps removed or *** 296 patients,87(29%)h.d h.perplastic polyps,82(28%)h.d fundic gland polyps and 5(1.7%)h.d adenomatous *** polyps were significantly associated with.positive *** status compared with.fundic gland polyps(OR=4.621;95%CI:1.92-11.13,P=0.001).h.perplastic polyps were also found to be significantly associated with.portal h.pertensive gastropath. compared with.fundic gland polyps(OR=6.903;95%CI:1.41-33.93,P=0.0174).Out of 296 patients,30(10.1%)h.d a followup endoscopy with.a mean duration of 26±16.3 *** development of cancer was not noted in any of th. patients during follow up *** ON:Gastric h.perplastic polyps were significantly associated with.positive *** status and portal h.pertensive gastropath. as compared with.fundic gland polyps.

关键词： Gastric polyps Fundic gland polyp h.perplasticpolyp Adenomatous polyps Ch.onic gastritis h.licobacter pylori

Experimental Investigation of th. Natural and Forced Convection on Solidification of Sn-3wt.%Pb Alloy Using a Bench.ark Experiment

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Experimental Investigation of the Natural and Forced Convect...