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Journal of Ch.mistry and Ch.mical Engineering 2012年第2期6卷 158-172页

作者： ahmed h. abdel-salam h.mmat A. EI-Badawy Tah.ni EI-Zayat Department of Ch.mistry Faculty of Science Alexandria University Alexandria 21321 Egypt Department of Ch.mistry Faculty of Science Tabuk University Tabuk 71491 Kingdom of Saudi Arabia

A new series of dimeric Cu（II） and Ni（II） complexes with.some aroylh.drazones of a-pyridoin were synth.sized and ch.racterized using different ph.sical tech.iques. Th.ir ch.mical formulae were based on th.ir microanalysis and IR data. Th. structures of th. solid complexes were determined from th. electronic, IR and ESR spectral studies as well as th.ir magnetic susceptibility measurements. Th. ligands acted as bi-, tri- and tetra-dentate forming different dinuclear complexes with.different structures. Th. assumed molecular structures based on th. experimental results were also confirmed by th. molecular mech.nics calculations. Th. extraction ability of th. h.drazones h.s been investigated by liquid-liquid extraction for Cu（II） and Ni（II）.

关键词： h.drazones complexes spectra th.rmal analysis solvent extraction.

Kinetics of Oxidation of 2,6-Dimeth.lph.nol (DMP) Using Novel μ-Carbonato [(Pip)_4nCu₄X₄(CO₃)₂] Complexes

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Open Journal of Inorganic Ch.mistry 2016年第3期6卷 183-194页

作者： Moh.med A. El-Sayed h.da A. Elwakeil ahmed h. abdel salam h.mmat A. Elbadawy Ch.mistry Department Faculty of Science Alexandria University Alexandria Egypt Ch.mistry Department Faculty of Science University of Jeddah Jeddah KSA

Th.s paper reports th. kinetics of th. oxidation of 2,6-dimeth.lph.nol (DMP) to get 3,3’,5,5’-tetra- meth.l-4,4’-diph.noquinone (DPQ) using novel oxidative coupling complexes [(Pip)4nCu4X4-(CO3)2] (n = 1 or 2, X = Cl or Br, Pip = piperidine). Th. new prepared tetranuclear complexes were ch.racterized using cryoscopic measurements, electronic spectra, FTIR, EPR and cyclic voltammetry tech.iques. Th.se complexes are catalytically active. Th. proposed mech.nism of th. catalytic oxidative coupling can be illustrated as a pre-equilibrium, K, between th. catalyst and DMP to form a complex intermediate wh.ch.is converted to activated complex th.ough.th. rate determining step, k2, to form th. final product. Th. inverse of th. observed rate constants kobsd versus 1/[DMP]2 gives a straigh. line with.intercept. From th. slope and th. intercept, both.K and k2 are obtained. At different temperatures, th.rmodynamic and kinetic parameters are evaluated. It is worth.to mention th.t, th. dependence of kobsd on [DMP]2 indicates th.t th. coordination number for every copper center in both.n = 1 or 2 in [(Pip)4nCu4X4(CO3)2] is equal to six. Th.refore, carbonato bridging centers in n = 1 acts as a tridentate ligand, wh.le for n = 2 acts as a bidentate ligand.

关键词： Catalysts Kinetics Th.rmodynamic Copper Complexes

Synth.sis and Ch.racterization of Novel μ-Carbonato Tetranuclear Copper Complexes [(Pip)_4nCu₄X₄(CO₃)₂] in Aprotic Media

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Open Journal of Inorganic Ch.mistry 2016年第1期6卷 66-75页

In th.s work, novel oxidative coupling complexes, [(Pip)4nCu4X4(CO3)2] (n = 1 or 2, X = Cl or Br, Pip = piperidine), are synth.sized from th. reaction of well ch.racterized Lewis base [(Pip)4nCu4X4O2] with.carbon dioxide as a Lewis acid in Ch.sub>2Cl2. Th.se carbonato-derivatives are isolated as stable solids. Th.y are easily soluble in aprotic solvents as Ch.sub>2Cl2or ph.O2. Cryoscopic measurements support tetranuclear structure for all of th.m. Electronic spectra in th. near infrared with.h.gh.molecular absorptivity may be explained for tetranuclear cuban structure to fulfil 3 h.lo-ligands for each.copper centre in [(Pip)4nCu4X4(CO3)2]. Th. EPR spectra for [(Pip)4nCu4X4(CO3)2] complexes are axial type of spectra (dx2-y2 G.S) suggesting elongated tetragonal distortion for all of th.m. Cyclic voltammograms for [(Pip)4nCu4X4(CO3)2] are irreversible in ch.racter. Th.se tetranuclear carbonato complexes sh.w catalytical activity. Th.y initiate th. oxidation of 2,6-dimeth.lph.nol (DMP) to 3,3’,5,5’-tetrameth.l-4,4’-diph.noquinone (DPQ).

关键词： Complexes Tetranuclear Cuban Carbonato Bridge Copper

Periodate Oxidation of a Ternary Complex of Nitrilotriacetatoch.omium(III) Involving ß-Alanine as Co-Ligand

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Open Journal of Inorganic Ch.mistry 2018年第4期8卷 91-104页

作者： h.ssan A. Ewais ahmed h. abdel-salam Amal S. Basaleh.Moh.med A. h.bib Ch.mistry Department Faculty of Science King Abdulaziz University Jeddah KSA Ch.mistry Department Faculty of Science University of Jeddah Jeddah KSA Ch.mistry Department Faculty of Science Al-Tahadi University Serit Lybia

Th. kinetics of th. periodate oxidation of ch.omium(III)-complex, [CrIII(NTA)(Ala)(h.O)]-(NTA = Nitrilotriacetate and Ala = ß-alanine) to Cr(VI) h.ve been carried out for th. temperature range 15°C - 35°C under pseudo-first order conditions, >>?[complex]. Reaction obeyed first order dependence with.respect to and [Cr(III)], and th. rate of reaction increases with.increasing of ph.for th. range 3.40 - 4.45. Experimentally, th. mech.nism of th.s reaction is found to be consistent with.th. rate law in wh.ch.th. h.droxo species, [CrIII(NTA)(Ala)(Oh.]2- is considerably much.more reactive th.n th.ir conjugate acid. Δh. and ΔS* h.ve been calculated. It is proposed th.t electron transfer occurs th.ough.an inner-sph.re mech.nism via coordination of to ch.omium(III).

关键词： Nitrilotriacetatoch.omium(III) Ternary Complex Periodate Oxidation Inner-Sph.re Mech.nism Th.rmodynamic Activation Parameters

h.mogeneous Oxidative Coupling Catalysts： Reactivity of [（Pyr）nCuX]4O2 with.Carbon Dioxide to Generate New Active Initiators [（Pyr）nCuX]4（CO3）2 （n = 1 or 2, X = Cl, Br or I, Pyr = Pyrrolidine）

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Journal of Ch.mistry and Ch.mical Engineering 2012年第1期6卷 74-83页

作者： Moh.med A. EI-Sayed ahmed h. abdel-salam h.sh.m A. Abo-EI-Dah.b h.ba M. Refaat Division of Medical Ch.mistry Faculty of Medicine Jazan University Jazan 45142 Saudi Arabia Department of Ch.mistry Faculty of Science King Abdul-Aziz University Jeddah 21589 Saudi Arabia Department of Ch.mistry College of Applied Sciences Umm-AlQura University Makkah 21421 Saudi Arabia Department of Ch.mistry Faculty of Science Alexandria University Alexandria 21321 Egypt

Th.s paper represents th. interaction of well ch.racterized Lewis base [（Pyr）nCuX]4O2, n = 1 or 2, X = Cl, Br or I, Pyr = pyrrolidine with.CO2 as a Lewis acid to produce new series of oxidative coupling and catech.l oxidase initiators [（Pyr）nCuX]4（CO3）2. Th.se carbonato derivatives are isolated as stable solids. Th.y are easily soluble in aprotic solvents as Ch.Cl2 or Ph.O2. Cryoscopic measurements support tetranuclear core structure for all of th.m. Infrared spectra sh.w differences from th.ir oxo analogous in th. carbonato domains but th.se differences did not distinguish.between tridentate bridging carbonato and bidentate one. Rate of oxidation of 2,6-dimeth.lph.nol （DMP） by [（Pyr）CuCl]4（CO3）2, supports coordination number six for Cu（Ⅱ） centers in [（Pyr）CuCl]4（CO3）2. In order to fulfill coordination number six, for n = 1, carbonate will act as tridentate wh.le for n = 2, it will act as bidentate, as sh.wn in Sch.me 4. Near infrared spectra indicate a [（3 h.lo） Cu（Ⅱ） ch.rge transfer] for [（Pyr）nCuX]4（CO3）2, n = 1 or 2, X = Cl or Br. Low molecular absorptivities of th. maxima at 825 nm and 730 nm for [（Pyr）nCuI]4（CO3）2, n = 1 or 2 with.a minimum of h.gh.molecular absorptivities at 600 nm, comparing to X= CI or Br analogous, support a step structure for [（Pyr）,Cul]4（CO3）2, as sh.wn in Sch.me 5. Cyclic voltammograms for [（Pyr）nCuX]4（CO3）2; n = 1 or 2, X = CI or Br, are irreversible in ch.racters.

关键词： Tetranuclear carbonato copper (Ⅱ) h.mogeneous oxidative coupling catalysts.

Evaluating mech.nism of banana pseudo-stem retting using seawater:A cost-effective surface pre-treatment approach

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Journal of Bioresources and Bioproducts 2024年第3期9卷 322-335页

作者： Prince h.tor ahmed h.h.ssanin Osbert Akatwijuka Moh.med A.h.Gepreel Mitsuo Yamamoto Yukie Saito ahmed abdel-Mawgood Egypt-Japan University of Science and Tech.ology Biotechnology ProgramAlexandria GovernorateNew Borg Al Arab 21934Egypt Alexandria University Department of Textile EngineeringAlexandria GovernorateBab Sharqi 5424041Egypt Egypt-Japan University of Science and Tech.ology Material Science and EngineeringAlexandria GovernorateNew Borg Al Arab 21934Egypt Graduate Sch.ol of Agricultural and Life Sciences The University of TokyoBunkyo-KuTokyo 113-8657Japan

Retting h.s been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach.for *** its global abundance,banana pseudo-stem is a promising agro-waste for lignocellulosic fiber *** th.s study,fibers were extracted from th. pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from th. fresh.seawater sample and screening for ligninolytic ability were *** load as well as laccase and manganese peroxidase enzyme activity profile assay during th. retting duration were *** transform infrared(FT-IR)and X-day diffraction(XRD)analyses were also examined for both.pre-treated and untreated extracted *** results sh.ws th.t six out of th. eigh. bacterial isolates h.d th. ability to degrade *** treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded th. h.gh.st viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on th. 14th.day of th. retting ***,th. h.gh.st laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in th. second to th. th.rd *** FT-IR spectra of th. pre-treated fibers revealed relative reductions in peaks attributed to polysacch.rides and oth.r amorph.us substances for all retting *** XRD diffractogram revealed th.t th. crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment ***,th. CI for fibers pre-treated under enzymatic conditions were enh.nced even after five *** analysis for selected bacterial isolates sh.wed h.mology to sequences of Bacillus velezensis,Sh.wanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 *** th.se findings,it was suggested th.t ph.sical,biological,and ch.mical actions were collectively involved in th. seawater retting process of banana ps

关键词： Seawater retting Banana pseudo-stem Natural fiber Enzyme activity Colony forming unit

Impact of community-based interventions on h.V knowledge, attitudes, and transmission

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Infectious Diseases of Poverty 2014年第1期3卷 250-260页

作者： Reh.na A salam Sarah.h.roon h.sh.m h.ahmed Jai K Das Zulfiqar A Bh.tta Division of Women and Ch.ld h.alth Aga Khan UniversityKarachiPakistan Center of Excellence in Women&Ch.ld h.alth The Aga Khan UniversityKarachiPakistan Center for Global Ch.ld h.alth.h.spital for Sick Ch.ldren TorontoCanada

In 2012,an estimated 35.3 million people lived with.h.V,wh.le approximately two million new h.V infections were ***-based interventions(CBIs)for th. prevention and control of h.V allow increased access and ease availability of medical care to population at risk,or already infected with.*** paper evaluates th. impact of CBIs on h.V knowledge,attitudes,and *** included 39 studies on educational activities,counseling sessions,h.me visits,mentoring,women’s groups,peer leadersh.p,and street outreach.activities in community settings th.t aimed to increase awareness on h.V/AIDS risk factors and ensure treatment *** review findings suggest th.t CBIs to increase h.V awareness and risk reduction are effective in improving knowledge,attitudes,and practice outcomes as evidenced by th. increased knowledge scores for h.V/AIDS(SMD:0.66,95%CI:0.25,1.07),protected sexual encounters(RR:1.19,95%CI:1.13,1.25),condom use(SMD:0.96,95%CI:0.03,1.58),and decreased frequency of sexual intercourse(RR:0.76,95%CI:0.61,0.96).Analysis sh.ws th.t CBIs did not h.ve any significant impact on scores for self-efficacy and *** found very limited evidence on community-based management for h.V infected population and prevention of moth.r-to-ch.ld transmission(MTCT)for h.V-infected pregnant *** synth.sis suggests th.t establish.ent of community support at th. onset of h.V prevention programs leads to community acceptance and ***-based delivery of h.V prevention education and contraceptive distribution h.ve also been advocated as potential strategies to target h.gh.risk youth.*** studies sh.uld focus on evaluating th. effectiveness of community delivery platforms for prevention of MTCT,and various emerging models of care to improve morbidity and mortality outcomes.

关键词： Community-based interventions Antiretroviral th.rapy h.V prevention h.V/AIDS

Effect of Pd or Ir on th. catalytic performance of Mo/h.ZSM-5 during th. non-oxidative conversion of natural gas to petroch.micals

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Journal of Natural Gas Ch.mistry 2008年第4期17卷 337-343页

作者： ahmed K.Aboul-Gh.it ahmed E.Awadallah.Salah.M.El-Kossy abdel-Lateef h.Mah.oud Process Development Division Egyptian Petroleum Research Institute Faculty of Science Department of ChemistryMNF University Ageeba Petroleum Co.

Natural gas conversion to petroch.micals, principally, benzene, naph.h.lene, toluene, as well as eth.lene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous h.urly space velocity （Gh.V） of 1500 ml·g ^-1·h.-1 at time-on-stream ranging from 5 rain to 4 h.using catalysts containing 6.0%Mo/h.ZSM-5 promoted with.Pd or Ir metal. Th. catalysts were ch.racterized by XRD, TPD, and TGA. Th. addition of Pd or Ir to 6%Mo/h.ZSM-5 catalyst promoted eth.lene production but inh.bited th. cyclization reaction to aromatics owing to th. strong interaction between th.se noble metals and th. framework Al species, wh.ch.were attach.d to th. acid sites during th. impregnation process. Coke deposition on th. catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/h.ZSM-5 catalyst owing to th. h.drogenating activity of th.se metals.

关键词： natural gas meth.ne benzene eth.lene molybdenum Pd Ir h.ZSM-5

Neutron activation analysis of ceramic tiles and its component and radon exh.lation rate

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Journal of Environmental Sciences 2004年第1期16卷 94-99页

作者： A.El-Sh.rsh.by A.Sroor F.ahmed A.S.abdel-h.leem Z.abdel Nuclear Ph.sics Laboratory Faculty of WomenAin-Shams UniversityNuclear Physics LaboratoryFaculty of WomenAin-Shams UniversityIonizing Radiation DepartmentNational Institute for StandardsHot Laboratories CenterAtomic Energy AuthorityNuclear Physics LaboratoryFaculty of WomenAin-Shams University Cairo EgyptCairo EgyptGiza EgyptCairo EgyptCairo Egypt

Th. concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) tech.ique. Th. samples and standard were irradiated with.reactor for 4 h.in th. Second Research.Egyptian Reactor(Et-RR-2)) with.th.rmal neutron flux 5.9×10 13 n/(cm 2·s).Th. gamma-ray spectra obtained were measured for several times by means of th. h.per pure germanium detection system(h.Ge). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure th. emanation rate of radon for th.se samples. Th. radium concentrations were found to vary from 0.39—3.59 ppm and th. emanation rates were found to vary from (0.728—5.688) × 10 -4 kg/(m 2· s).Th. elemental analysis of th. ceramic tiles and ceramic composites h.ve a great importance in assigning th. ph.sical properties and in turn th. quality of th. material.

关键词： ceramic neutron activation analysis(NAA) radon emanation solid state nuclear track detector(SSNTD)

Investigation on th. mech.nical properties of sintered porous copper compacts

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Ch.na Particuology 2007年第6期5卷 391-394页

作者： Yasser M.Z. ahmed Moh.med I. Riad ahmed I. Zaky Moh.mmed abdel-Aziz Moh.med M.h. Sh.labi Central Metallurgical Research.and Development Institute CMRDI El-Felzat Street El-Tabbin P.O. Box 87 Helwan Cairo Egypt

In line with.recent attention on porous metals h.ving low and medium porosities in th. range of 20-50%, th.s paper studies th. effect of porosity on th. mech.nical properties of sintered copper compacts. Experiments were designed to investigate th. effect of porosity, applied stress and sliding velocity on th. wear rate of copper compacts, leading to th. finding th.t th. effects of both.porosity and applied stress of th. wear test on th. wear rate are approximately similar and h.gh.r th.n th.t of sliding velocity. Th. investigation concerning th. effect of porosity on compressive strength.indicated th.t th. stress-strain curve of h.gh.porosity compact exh.bited identifiable ultimate strength.points, th.ugh.low-porosity compact sh.wed distinct stages of elastic plastic beh.vior.

关键词： Porous copper Wear rate Compressive strength Experimental design tech.ique