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Modeling of soil heterogeneity and its effects on seismic response of multi-support structures

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Earthquake Engineering and Engineering Vibration 2015年第3期14卷 423-437页

作者： Laib A Laouami N slimani A National Center of Applied Research in Earthquake Engineering CGS University of Science and Technology Houari Boumediene Civil Engineering Department

This paper addresses the analytical evaluation of soil lateral heterogeneity effects,especially the random fluctuations of the soil layer’s predominant frequency,on the spatial coherency of ground motion and the seismic response of multi-support structures.A coherency probabilistic model is *** this model,the spatial variation of motion is attributed to wave passage effects,effects of loss of coherence in the bedrock motion and particularly site response effects(based on the assumption of vertically propagating shear-waves through a horizontal layer with random characteristics).The results indicate that soil lateral heterogeneity effects tend to cause diminution of the values of the total coherency *** diminution is not limited to the vicinity of the mean resonant frequency of the layer,but reaches considerably high frequencies even for relatively low values of coefficient of variation(CV of 5 to 15%).Therefore,the trend of the total coherency function(exponential decay) can be influenced significantly by site ***,the proposed coherency model is applied for two different support seismic *** results indicate that the greater the soil heterogeneity,the larger are the dynamic displacements and shear forces in the columns of the oscillator(i.e.,support structure).Furthermore,these two components of the response are influenced differently by soil heterogeneity effects.

关键词： coherency function spatial variability,soil latera

Synthesis and characterization of Co1-2xNixMnxCeyFe2-yO4 nanoparticles

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Journal of Rare Earths 2020年第2期38卷 188-194页

作者： Munirah Abdullah Almessiere Yassine slimani Abdulhadi Baykal Department of Physics College of ScienceImam Abduirahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Biophysics Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia

Spinel ferrite Co1-2 xNixMnxFe2-yCeyO4(0.0≤x=y≤0.3) nanoparticles(NPs) were prepared by sol-gel auto-combustion *** synthesized NPs were examined using several techniques such as X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM) coupled with EDX and elemental mapping,transmission electron microscopy(TEM),Fourier-transform infrared spectroscopy(FT-IR),and a vibrating sample magnetometer(VSM).The analysis of the crystal structure and the phase identification of samples indicates the formation of spinel cubic phase with the occurrence of CeO2 as secondary phase when the content of Ce substitution element *** addition,all produced samples exhibit cubic symmetry with space group *** confirms the presence of two phases,i.e.,the cubic spinel ferrite and the cubic cerium oxide(CeO2).The characteristics of hysteresis loops reveal the soft ferrimagnetic nature of the different synthesized *** saturation(Ms) and remanent(Mr) magnetizations fall on increasing the content of substituting *** with pure CoFe2O4 NPs,the value of coercive field(Hc) slightly increases for x=y=0.1 and x=y=0,2 ***,Hc reduces with further increasing the x and y *** squareness ratio is found to be in the 0.528-0.400 interval,indicating the single domain NPs with uniaxial anisotropy for the different produced *** magneto crystalline anisotropy constant(Keff),anisotropy field(Ha),magneton number(nB) and the demagnetizing field(N) were also determined and discussed.

关键词： Cobalt ferrite Spinel ferrites Rare earth substitution Magnetic properties Rare earths

Caffeic acid and quercetin exert caspases-independent apoptotic effects on Leishmania major promastigotes, and reactivate the death of infected phagocytes derived from BALB/c mice

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Asian Pacific Journal of Tropical Biomedicine 2017年第4期7卷 321-331页

作者： Radia Belkhelfa-slimani Bahia Djerdjouri Laboratory of Cellular and Molecular Biology Faculty of Biological SciencesUniversity of Sciences and Technology Houari BoumedieneAlgiersAlgeria

Objective: To investigate the leishmanicidal effects of two antioxidants, caffeic acid and quercetin on Leishmania major(***) promastigotes in vitro, and their immunomodulatory effects on infected phagocytes derived from susceptible BALB/c ***: Caffeic acid and quercetin-induced cell death was examined by Pi-Hoechst double staining of *** promastigotes and MTT assay, in the presence or absence of protease inhibitors in *** acid or quercetin were administered subcutaneously to BALB/c mice infected with *** promastigotes through a dorsal air *** oxide and superoxide anion production by phagocytes infiltrating the air pouch and the expression of inducible nitric oxide synthase(i NOS), tumor necrosis factor alpha(TNF-a) and nuclear factor kappa B in the air pouch membrane were therefore evaluated using appropriate ***: Caffeic acid and quercetin displayed a dose-dependent cytotoxic effect against *** promastigotes, and induced cell death via caspases-independent *** vivo, *** promastigotes inoculation into air pouch cavity of BALB/c mice leads to a sequential influx of neutrophils(hours), followed by macrophages(days).Results showed that *** delayed apoptosis of infected neutrophils and macrophages by the cleavage of the nuclear factor kappa B p65^(RelA) subunit, and persisted by inhibiting TNF-a and i NOS expression and reactive oxygen species *** acid or quercetin restored reactive oxygen species production and TNF-a-induced i NOS activity, and abrogate apoptosis delay of infected ***: The leishmanicidal effect of caffeic acid and quercetin on promastigotes and amastigotes, as well as reactivation of infected phagocytes apoptosis, suggested a potential therapeutic role against cutaneous leishmaniasis.

关键词： Apoptosis Leishmania major Phagocytes iNOS NF-kB TNF-a

Expressions of Collagen I and III in Mesenchymal Stem Cells Co-cultured with Ligament Fibroblasts

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生物医学工程学杂志 2005年第S1期22卷 75-76页

作者： Said slimani LEMTA-UMR 7563 CNRS/INPL/UHP 54500 Vandoeuvre-lès-Nancy France

Comparison of rare earths doping(neodymium and samarium) on structural and magnetic properties of Ni-Zn-Bi nanoferrites

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Journal of Rare Earths 2024年第3期42卷 534-542,I0004页

作者： Shilpa Taneja Preeti Thakur Dinesh Kumar Yassine slimani Atul Thakur NanoLatticeX Amity University HaryanaGururam122413HaryanaIndia Nanotechnology Wing Innovative Science Research SocietyShimla177002India Centre for Nanotechnology Amity University HaryanaGururam122413HaryanaIndia Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia School of Electronics and Information Engineering Nanjing University of Information Science&TechnologyNanjing210044China

Excellent magnetic properties in ferrites are required for high-frequency applications and for wastewater treatment. Thus, the present study shows the comparison of magnetic and structural properties of Nd and Sm substituted Ni-Zn-Bi ferrites with the series Ni_(0.5)Zn_(0.5)Bi_(0.04)Nd_(x)Fe_(1.96-x)O_4(with step size 0.002)and Ni_(0.5)Zn_(0.5)Bi_(0.04)Sm_(x)Fe_(1.96-x)O_4(with step size 0.02) prepared using citrate precursor method. The impact of the substitution of rare earth ions(Nd and Sm) on magnetic properties of the synthesized samples is observed using a vibrating sample magnetometer(VSM). The saturation magnetization values enhance considerably from 52 to 58 emu/g for Nd^(3+)ions and 39 to 57 emu/g for Sm^(3+) ions, thus, making these materials magnetically hard. Further, the higher value of coercivity is also observed ranging from133 to 167 Oe for Nd^(3+)ions and 81 to 155 Oe for Sm^(3+) ions. The shape of hysteresis loops indicates a super paramagnetic and ferromagnetic behavior in the obtained samples. The squareness ratio value is<0.5, suggesting the uniaxial anisotropy of particles and hence, these ferrites are suitable for microwaveabsorbing and in permanent magnetic materials. The X-ray diffraction(XRD) pattern shows the formation of pure cubic crystallites, where, lattice parameters range from 0.840 to 0.839 nm and from 0.838to 0.839 nm for Nd^(3+)and Sm^(3+) ions substitution, respectively. The crystallite size ranges between 28.63to 29.89 nm and 18.33 to 26.23 nm, for substitution of Nd^(3+)and Sm^(3+) ions, respectively. Field emission scanning electron microscopy(FESEM) shows the formation of homogeneous grains, whereas, energy dispersive spectrometer(EDS) counts describe the purity of the samples. The Sm concentration x = 0.10has the maximum surface area with value of 42.6 m^(2)/g which proves to be having good data storage application due to high surface area. The zero-field cooled(ZFC) and field cooled(FC) data show that Nddoped Ni-Zn-Bi nano

关键词： Citrate precursor X-ray diffraction Vibrating sample magnetometer Coercivity Field emission scanning electron microscopy Rare earths

Co-substitution of zirconium and neodymium on hyperfine interactions and AC susceptibility of SrFe12O19 nanohexaferrites

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Journal of Rare Earths 2020年第3期38卷 265-273页

作者： M.A.Almessere Y.slimani H.Güngünes A.Baykal Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Biophysics Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Physics Hitit University19030Cevre Yolu Bulvan-CorumTurkey Department of Nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia

This study presents the influence of Zn and Nd co-substitution on structure,morphology,AC susceptibility and ZFC-FC magnetizations of Sr nanohexaferrites(NHFs),SrFe12-x(Zn,Nd)xO19(0.0≤x≤1.0),which was produced by sol-gel *** powder patterns,scanning electron microscopy(SEM) and high-resolution transmission electron spectroscopy(HR-TEM) approve the synthesis of Sr M-type *** spectra show that Zn^2+ions occupy 2 b and 4f1 sites while Nd3+ions locate at 2 a,4f2 and 12 k *** magnetic properties of the produced Sr-NHFs were investigated also by ZFC-FC magnetizations and AC *** to the MFC-MZFC results(between 2 and 400 K),no blocking temperature was detected which indicates the ferromagnetic(FM) behavior of *** lower temperatures,a super-spin glass like behavior is *** AC susceptibility indicates that the magnetic interactions are improved due to the inclusion of low content(x=0.1) of Nd^3+and Zn^2+ions into the ***,with further increasing the Nd^3+and Zn^2+contents(x=0.9),the magnetic interactions are weakened.

关键词： Sr hexaferrites Rare earths Mossbauer spectroscopy AC susceptibility ZFC-FC

Modeling Water Adsorption and Retention of Building Materials From Pore Size Distribution

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Journal of Renewable Materials 2019年第6期7卷 547-556页

作者： Abdelkrim Trabelsi Zakaria slimani Akli Younsi Joseph Virgone Rafik Belarbi Univ Lyon CNRSINSA-LyonUniversitéClaude Bernard Lyon 1CETHIL UMR5008F-69621VilleurbanneFrance University of La Rochelle CNRSLaSIEUMR-7356Avenue Michel Crépeau17042 La Rochelle Cedex 1France

Water adsorption and capillarity are key phenomena involved during heat and moisture transfer in porous building *** account for interaction between solid matrix,liquid water and moist *** are considered through Water Vapor Adsorption Isotherm(WVAI)and Retention Curve(RC)functions which are constitutive laws characterizing water activity within a porous *** objective of this paper is to present a water vapor adsorption and retention models built from multimodal Pore Size Distribution Function(PSDF)and to see how its parameters modify moisture storage for hygroscopic and near saturation *** microstructure of the porous medium is represented statistically by a bundle of tortuous parallel pores through its ***,the influence of contact angle and temperature on storage properties were ***,a parametric study was performed to see the influence of the PSDF shape on storage *** cases were studied considering the number of modalities,the weight of each modality and the dispersion around mean ***,as a validation,the proposed model for WVAI were compared to existing model from literature showing a good *** study showed that the proposed models are capable to reproduce various shapes of storage *** also highlighted the link between microstructure and adsorption-retention phenomena.

关键词： Water vapor adsorption capillarity pore size distribution WVAI and RC modeling porous building materials

Morphology and magnetic traits of strontium nanohexaferrites:Effects of manganese/yttrium co-substitution

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Journal of Rare Earths 2019年第7期37卷 732-740页

作者： M.A.Almessiere Y.slimani H.S.El Sayed A.Baykal Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Biophysics Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia

Doped strontium(Sr) hexaferrites appeared potential candidates for microwave absorber *** by this idea, we examined the influence of manganese(Mn) and yttrium(Y) co-substitution on the microstructures,morphology and magnetic properties of Sr nanohexaferrites(Sr1-xMnxFe12-yYyO19,where 0.0 ≤ x = y ≤ 0.5) synthesized via citrate sol-gel auto-combustion technique. As-prepared samples were thoroughly characterized using diverse analytical tools. X-ray diffraction pattern reveals a single Mhexagonal crystalline phase. FE-SEM, TEM, HR-TEM show a hexagonal platelet-like structure. The magnetic hysteresis loops(measured at room and low temperature) of the as-prepared nanohexaferrites exhibit ferromagnetic(FM) behavior. Magnetic parameters including the saturation magnetization,remanence, coercive and magneto-crystalline anisotropy field are found to decrease with the increase in Mn2+ and Y3+ contents. Zero-and normal-field cooled magnetization measurements in the range of 2-400 K display the complete absence of blocking temperature, confirming the characteristic ferromagnetic behavior of the proposed composition.

关键词： Strontium hexaferrite Sol-gel auto-combustion Microstructure Morphology Magnetic properties Rare earths