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Journal of Rare Earths 2019年第4期37卷 416-421页

作者： A.G.el Hachimi M.L.Ould NE A.el Yousfi A.Benyoussef A.el Kenz Laboratory of condensed Matter and Interdisciplinary Sciences (LaMCScI) Associé Au CNRST (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V Hassan Ⅱ Academy of Science and Technology

By using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and Pm. In this calculation, we used Wien2 k code based on full potential linearized augmented plane waves(FP-LAPW) method with the modified Becke-Johnson(mBJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and Pm codoping leads to an increase in the band gap. electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications.

关键词： Zinc oxide Rare earth Density functional theory Modified Becke-Johnson Magnetic properties Spintronics

Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks M-MOF-74(M=co, Ni, Mg, Zn)

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Science China Chemistry 2020年第7期63卷 881-889页

作者： Yanan Si Wenjing Wang el-Sayed M.el-Sayed Daqiang Yuan State Key Laboratoty of Structural Chemistry Fujian Institute o f Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academy of Sciences Beijing 100049China Chemical Refining Laboratory Refining DepartmentEgyptian Petroleum Research InstituteNasr CityCairoEgypt

The unique adsorption performance of metal-organic frameworks(MOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy-and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechanism to solve the challenge of hydrogen isotope separation. Herein we analyze M-MOF-74(M=co, Ni, Mg, Zn), featuring a hexagonal channel about 11 ? and high density of open metal sites, for their ability to separate and purify deuterium from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders co-MOF-74 as an optimal adsorbent for the capture of deuterium from hydrogen isotope mixtures in a simulated industrial process.

关键词： hydrogen isotope separation breakthrough experiment MOF-74

Detection of oqxA and oqxB efflux pump genes among nosocomial coliform bacilli:An observational cross-sectional study

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Journal of Acute Disease 2021年第3期10卷 117-121,I0001页

作者： Basant Mostafa gabr Afaf Sayed Ahmed Zamzam Eman Ahmed Eisa Ghada Foad el-Baradey Maii Atef Shams eldeen Microbiology and Immunology Department Faculty of MedicineTanta UniversityEl-GaishTanta Qism Tanta GharbiaEgypt 2Anesthesiology and Intensive Care DepartmentFaculty of MedicineTanta UniversityEl-GaishTanta Qism 2TantaGharbiaEgypt

Objectives:To identify and test the antibiotic susceptibility of nosocomial coliform bacilli and investigate the presence of oqxA and oqxB genes among the multidrug-resistant(MDR)***:One hundred and twenty different healthcare-associated infection samples were *** bacilli were isolated,identified by conventional methods,and then antibiotic susceptibility tests were done using the VITEK2 system and disk diffusion *** operon was identified using a conventional PCR-based *** and oqxB genes were compared between MDR Klebsiella pneumonia(***)phenotypes and MDR Escherichia coli(***)***,oqxAB operons were compared between phenotypes of *** and *** ***:Seventy coliform bacilli were isolated with the predominance of *** and ***,82.1%of *** strains and 53.3%of *** isolates were MDR *** more oqxB genes alone were found in MDR *** than that in MDR *** phenotypes(χ^(2)=10.160,P=0.003).OqxAB operon was significantly more in MDR phenotypes of *** than that in the susceptible phenotypes(Pcol,most probably suggested functional ***:MDR coliform bacilli are strongly implicated in healthcare-associated *** should be paid to the presence of oqxAB pump,as an important mechanism in the development of resistance against many antimicrobials because it contributes to co-resistance with other categories;therefore,this pump could be a good target for efflux pump inhibitors.

关键词： Healthcare-associated infection coliform bacilli Multidrug-resistant efflux pump oqxA gene oqxB gene

Optical and magnetic properties of perovskite materials:Ba_(0.3)La_(0.7)Ti_(0.3)Fe_(0.7)O_(3) and Ba_(0.1)La_(0.9)Ti_(0.1)Fe_(0.9)O_(3)

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Journal of Rare Earths 2022年第4期40卷 652-659,I0005页

作者： Fatima el Bachraoui Zakaria Chchiyai Youssef Tamraoui Hassan el Moussaoui Jones Alami Bouchaib Manoun Materials Science Energy and Nano-engineering Department(MSN)University Mohammed VI Polytechnic43150BenguerirMorocco Hassan First University of Settat FSTRayonnement-Matière et InstrumentationS3M26000SettatMorocco Materials and Nanomaterials Center Moroccan Foundation for Advanced ScienceInnovation and Research10100RabatMorocco

Structural,optical and magnetic properties are reported for new synthesized perovskite ***_(0.3)La_(0.7)Ti_(0.3)Fe_(0.7)O_(3) and Ba_(0.1)La_(0.9)Ti_(0.1)Fe_(0.9)O_(3) compositions were prepared via solid state reaction.X-ray analysis confirms that both compositions show feature of perovskite *** refinement method was used to confirm the phase formation and investigate the structure and space *** study demonstrates the formation of orthorhombic structure with Pnma space group for Ba_(0.3)La_(0.7)Ti_(0.3)Fe_(0.7)O_(3) while the composition Ba_(0.1)La_(0.9)Ti_(0.1)Fe_(0.9)O_(3) structure adopts Pbnm ***–vis spectroscopy measurements show very broad and intense UV–visible light absorption,the estimated band gap ranges between 2.07 and 2.15 *** measurements were carried out for the compositions Ba_(0.3)La_(0.7)Ti_(0.3)Fe_(0.7)O_(3) and Ba_(0.1)La_(0.9)Ti_(0.1)Fe_(0.9)O_(3).The hysteresis loops of both samples at 300 and 10 K show a strong ferromagnetic *** temperature dependent magnetization at 0.05 T under field-cooled(FC)and zero field cooled(ZFC)modes shows magnetic frustration or spin glass-like behavior.

关键词： Perovskites co-substitution effect Phase transition Band gap Ferromagnetic Visible light absorption

co oxidation and 4-nitrophenol reduction over ceria-promoted platinum nanoparticles impregnated with ZSM-5 zeolite

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Journal of Rare Earths 2022年第8期40卷 1247-1254页

作者： Zeinhom M.el-Bahy Mohammed T.Alotaibi Salah M.el-Bahy Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

Active new ceria-promoted platinum supported on ZSM-5 catalysts were prepared and characterized by X-ray diffraction(XRD),Fourier transform infrared spectra(FTIR),transform electron microscopy(TEM),temperature programmed desorption(TPD),and FTIR of co *** samples were prepared by the incipient wetness impregnation method and calcined at 500℃.The XRD patterns and FTIR spectra prove that the zeolite framework is kept unaltered after metal *** images prove the presence of Pt nanoparticles with particle size starting from 14 to 27 *** FTIR data suggest the formation of Pt-O-Ce ***-situ FTIR of co adsorption over reduced samples proves the presence of Pt~0 only,and no Pt^(n+)-co species are *** prepared catalysts were tested in both oxidation reaction(co oxidation) in the gas phase and in reduction reaction(4-nitrophenol reduction) in the aqueous ***,co oxidation by O_(2) results in the formation of a co_(2) peak at 2347 cm^(-1) as the only co oxidation product in the studied frequency *** intensity of the co_(2) peak increases after the addition of Ce,and it is 4 times higher in Pt_(1) Ce_(0.5)ZSM-5 than that in the Ce-free *** to the FTIR data and previous reports,the increase in the catalytic activity may be due to the formation of Pt-O-Ce ***,Ce-promoted Pt_(1) ZSM5 also exhibits enhanced catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol by NaBH_(4) in the aqueous *** first-order rate constant of the reduction increases ≈13 times after incorporating equal ratios of Pt and Ce(Pt_(1) Ce_(1)ZSM-5),and the activation energy(E_(a)) decreases to 40% of that in the reaction over Pt_(1) ZSM-5.

关键词： 4-Nitrophenol co oxidation TPD-co Platinum-cerium ZSM-5 Rare earths

Diffusion coefficient of vacancies and jump length of electrons in co_(1-x)Zn_(x)Fe_(2)O_(4)ferrites

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Journal of Advanced Ceramics 2012年第2期1卷 144-149页

作者： M.el-SAADAWY Physics Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh CityEgypt

A series of polycrystalline samples of co_(1-x)Zn_(x)Fe_(2)O_(4)where(x=0.1,0.2,0.3,0.4,0.5 and 0.6)were prepared by the usual ceramic technique.X-ray diffraction patterns confirmed the spinel cubic *** diffusion coefficients of oxygen vacancies were estimated from dc conductivity *** was noticed that the diffusion coefficient decreases with increasing Zn^(2+)*** increase of temperature increases the diffusion of lattice *** Curie temperature,lattice parameter and jump length of electrons were studied as a function of Zn^(2+)*** the correlation between the ionic radius and the radii of octahedral and tetrahedral sites,the theoretical lattice parameters were calculated and suggested cation distribution for the given ferrites was determined.

关键词： diffusion coefficient lattice parameter jump length and jump rate of vacancies Curie temperature cation distribution

Major and trace elemental analysis in milk powder by inductively coupled plasma-optical emission spectrometry(ICP-OES) and instrumental neutron activation analysis(INAA)

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Journal of Environmental Sciences 2003年第4期15卷 570-576页

作者： A.Sroor N.Walley el-Dine A.el-Shershaby A.S.Abdel-Haleem NuclearPhysicsLaboratory NuclearPhysicsLaboratoryNuclearPhysicsLaboratoryHotLaboratories FacultyofGirlsAinShamsUniversityCairoEgyptFacultyofGirlsAinShamsUniversityCairoEgyptFacultyofGirlsAinShamsUniversityCairoEgyptAtomicEnergyAuthorityCairoEgypt

Major and trace element in seven different kinds of milk powder were studied. The concentration of 24 elements were determined by ICP OES method, from these elements 9 elements determined by INAA. The determination of trace element contents of foodstuffs, especially milk as daily drink for all peoples age which being a complex food has great importance. The elemental analysis of milk is important both as an indicator of environmental contamination and because milk is a significant pathway for toxic metal intake and a source of essential nutrients for humans. The major elements are Ca, K, Mg, Na, P and S. While trace element are B, Ba, co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sb, Se, Sn, Sr, V, W and Zn. ICP OES technique is shown to be a powerful tool for trace determinations in powder samples. This is shown by its use for analysis of a series of the milk powders mentioned and comparative results of other direct technique such as instrumental neutron activation analysis. Analysis of both standard reference material A 11 milk powder and NBS Orchard leaves for quality accurance had been completed, and used for a relative method calculate. The importance of the major and trace elements to human health was discussed.

关键词： milk powder ICP OES INAA

Responses of co_2 in surface water in subtropical West Pacific to el Nio event

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Acta Oceanologica Sinica 2001年第1期20卷 39-50页

作者： Xing Runan 1, Ma Liming 2, Qiao Ran 2,Wang Zhanggui 21 .TrainingCenterofChineseMeteorologicalAdministration ,Beijing 10 0 0 81,China2 .NationalResearchCenterforMarineEnvironmentalForecasts ,StateOceanicAdministration ,Beijing 10 0 0 81,China

In order to investigate the relationships between the change of T co 2 , Δ P co 2 and SST, current, upwelling and biological activities during el Nio event in the subtropical Pacific, the responses of T co 2 and Δ P co 2 in surface water in the subtropical Pacific during el Nio and La Nina have been simulated using a three dimension carbon cycle model with biota pump. The results of numerical simulations show that T co 2 in sea water increases with reducing of SST during mature phase of el Nio in the subtropical West Pacific . At the same period ,the Kuroshio in this region was weakened ,the zonal currents were divergence , the upwelling carried the water with high concentrations of co 2 to the sea surface , so both of T co 2 and Δ P co 2 in surface water were increased . But T co 2 and Δ P co 2 were decreased during La Nina period. These simulated results confirmed the observations in 1982/1983 , 1986/1987 , 1991/1995 and 1997/1998 el Nio events .

关键词： co 2 el Nio the subtropical West Pacific

The comparison of the Wnt signaling pathway inhibitor delivered electrospun nanoyarn fabricated with two methods for the application of urethroplasty

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Frontiers of Materials Science 2016年第4期10卷 346-357页

作者： Xuran GUO Kaile ZHANG Mohamed el-AASSAR Nanping WANG Hany el-HAMSHARY Mohamed el-NEWEHY Qiang FU Xiumei MO State Key Lab for Modification of Chemical Fibers & Polymer Materials College of Chemistry & Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China Department of Urology Affiliated Sixth People's Hospital Shanghai Jiaotong University Shanghai 200030 China Polymer Materials Research Department Advanced Technology and New Material Institute City of Scientific Research and Technological Applications (SRTA-City) New Borg El-Arab City Alexandria 21934 Egypt Shanghai Aquatic Product Research Institute Shanghai 200030 China Department of Chemistry College of Science King Saud University Riyadh i 1451 Saudi Arabia Department of Chemistry Faculty of Science Tanta University Tanta 31527 Egypt Shandong International Biotechnology Park Development co. Ltd. Shanghai 200030 China

Urethral strictures were common disease caused by over-expression of extracellular matrix from fibroblast. In this study, we compare two nanoyarn scaffolds for improving fibroblasts infiltration without inhibition the over-expression of extracellular matrix. collagenlpoly（L-lactide-co-caprolactone）（colIP（LLA-CL）） nanoyarn scaffolds were prepared by conjugated electrospinning and dynamic liquid electrospinning, respectively, in addition, co-axial electrospinning technique was combined with the nanoyarn fabrication process to produce nanoyarn scaffolds loading Wntsignaling pathway inhibitor. The mechanical properties of the scaffolds were examined and morphology was observed by SEM. Cell morphology, proliferation and infiltration on the scaffolds were investigated by SEM, MTT assay and H＆E staining, respectively. The release profiles of different scaffolds were determined using HPLC. The results indicated that cells showed an organized morphology along the nanoyarns and considerable infiltration into the nanoyarn scaffolds prepared by dynamic liquid electrospinning （DLY）. It was also observed that the DLY significantly facilitate cell proliferation. The D-DLY could facilitate the infiltration of the fibroblasts and could be a promising scaffold for the treatment of urethra stricture while it may inhibit the collagen production.

关键词： biomaterials nanoyarn electrospinning inhibitor

Aspects of forest restoration and hydrology:the hydrological function of litter

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Journal of Forestry Research 2022年第2期33卷 543-552页

作者： Luara Castilho Pereira Leonardo Balbinot Marcelle Teodoro lima Julieta Bramorski Kelly Cristina Tonello Hydrology in Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of São Carlos(UFSCar)SorocabaSão PauloBrazil Hydrology in Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of Amapá(UNIFAP)MacapáAmapáBrazil

Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado *** study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the *** retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly *** litter accumulation at 46 years was significantly higher than that of the other succession *** litter mass was significantly higher than that of leaves and *** 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and *** the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field *** process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 ***,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado *** and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.

关键词： Forest hydrology Litter interception Stemflow Cerrado Águas Perenes Forest Water holding capacity