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Conduction properties of condensed lanthanum phosphates:La(PO_3)_3 and LaP_5O_(14)

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Journal of Rare Earths 2010年第3期28卷 321-328页

作者： Ines Hammas karima Horchani-Naifer Mokhtar Férid Research Unit of Rare Earth Materials National Research Center in Sciences of MaterialsB.P.95 Hammam-Lif2050Tunisia

Single crystals of LaP3O9·3H2O were prepared using a classical method of aqueous chemistry whereas those of the ultraphosphate LaP5O14 were obtained by flux *** treatment of LaP3O9·3H2O up to 700 °C allowed us to obtain the lanthanum polyphosphate La(PO3)*** conductivity as well as the vibrational study of the lanthanum ultraphosphate and polyphosphate were analysed in order to explain the mechanism of *** energies of 0.45 and 0.84 eV,deduced from the Arrhenius relation,were r...

关键词： condensed lanthanum phosphates electrical conductivity Grotthuss mechanism rare earths

Complex dynamics and bifurcation analysis for a Beverton-Holt population model with Allee effect

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International Journal of Biomathematics 2023年第7期16卷 165-196页

作者： karima Mokni Mohamed Ch-Chaoui MRI Laboratory FacultéPolydisciplinaire Khouribga Sultan Moulay Slimane University BP:145 Khouribga Principale25000Kingdom of Morocco

In this paper,we have derived a discrete evolutionary Beverton-Holt population *** model is built using evolutionary game theory methodology and takes into consideration the strong Allee effect related to predation *** have discussed the existence of the positive fixed point and examined its asymptotic ***,we demonstrated that the derived model exhibits Neimark-Sacker bifurcation when the maximal predator intensity is at lower *** chaotic behaviors are justified ***,to avoid these chaotic features and achieve asymptotic stability,we implement two chaos control methods.

关键词： Evolutionary game theory asymptotic stability Neimark-Sacker bifurcation chaos control

Combustion synthesis and luminescence properties of LaPO4： Eu （5%）

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Journal of Rare Earths 2009年第2期27卷 182-186页

作者： Mounir Ferhi karima Horchani-Naifer Mokhtar Férid Research Unit of Rare Earth Materials National Research Center in Sciences of Materials B.P. 95 Hammam-Lif 2050 Tunisia

Rare earth doped materials are an important type of phosphors due to their excellent performance such as stability at high temperature and light emission covering the entire visible domain. The combustion synthesis at acid pH of the monoclinic LaPO4： Eu（5%） powders was described. A mixture of La（NO3）3·6H2O, EuCly6H2O and （NH4）2HPO4 was used as anion precursor and glycin as fuel. The synthesis was followed by structure, morphology characterisation and luminescent properties of the obtained compound. The room temperature emission measurements under ultraviolet excitation at 254 nm were made for the emission transition ^5D0→^7FJ of this phosphor. The CIE （Commission Intemationale de L＇Eclairage） chromatic coordinates, dominant wavelength and colour purity were determined and compared to other luminescent materials obtained by other methods.

关键词： rare earth phosphates combustion optical materials luminescence chromaticity

Crystal structure and infrared spectrum of thallium holmium polyphosphate, TlHo(PO_3)_4

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Journal of Rare Earths 2008年第6期26卷 765-769页

作者： karima Horchani-Naifer Jaouher Amami Mokhtar Férid Unité de Recherches de Matériaux de Terres Rares Centre National de Recherches en Sciences des Matériaux

Crystals of thallium-holmium polyphosphate T1Ho（PO3）4 were grown by flux method technique and characterized by single crystal X-ray diffraction. Structure of T1Ho（PO3）4 was solved for the first time, and it crystallized in the monoclinic P21/n space group with the following unit-cell dimensions： a=1.02225（3） nm, b=0.88536（2） nm, c=1.09541（4） nm, β=105.888（1）°, V=0.95354（5） nm^3 and Z=4. The crystal structure was solved from 2174 independent reflections with final R1（F^2）=0.0442 and Rw（F^2）=0.0861 refined with 164 parameters. The atomic arrangement could be described as a long chain polyphosphate organization. Holmium atoms had eightfold coordination. The structure of T1Ho（PO3）4 consisted of HoO8 polyhedra sharing oxygen atoms with phosphoric group PO4. Infrared spectrum was investigated at room temperature in the frequencies range, 350--4000 cm^-1, showing some characteristic vibration bands of infinite chain structure of PO4 tetrahedra linked by bridging oxygen.

关键词： polyphosphate holmium crystal structure infrared spectroscopy rare earths

Benefits of Gum Arabic, for a Solitary Kidney Under Adverse Conditions:A Case Study

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Chinese Medicine and Culture 2018年第2期1卷 88-96页

作者： Mehrab Dashtdar karima Kardi Department of Integrative Medicine Dubai Specialized Medical Center and Medical Research LabAffiliated with Dubai Medical College and Dubai Pharmacy CollegeDubaiUnited Arab Emirates

Gum Arabic(GA,called E-414 in the EU food industry),a natural biopolymer resin is a dried exudation obtained from the stems and branches of natural strains of Acacia Senegal(L)*** consists mainly of high molecular weight polysaccharides and their calcium,potassium,and magnesium,which on hydrolysis yield arabinose,galactose,rhamnose,and glucuronic *** natural fiber of gum Arabic act as probiotics improves the absorption of minerals,especially calcium and helps to maintain a healthy balance of bacteria in the gastrointestinal(GI)***,transformation,or reprocessing of nitrogenous wastes(ammonia,urea,and uric acid)by the GI tract is a potentially low-cost means of switching for missing renal *** of nitrogen compounds to be inert orally by administration of gum Arabic is the safe solution either in normal renal function or renal *** this study,clinically,we observed a case of solitary kidney under adverse condition long‑term treating with gum Arabic the vast potential of bioactive phytochemicals as a nontoxic,efficient with uric acid and bilirubin lowering agent and anti‑inflammatory effects,considering the gum Arabic as a potential therapeutic supplement,beneficial in chronic renal failure,cardiovascular disease,pain management,and dental *** the nonexistent background concerning the benefits of gum Arabic,for a solitary kidney under adverse conditions,our study has confirmed that long‑term consumption of gum Arabic not only has no side effect but also protects multi-organs damage from drug adverse reactions and consequences of baseline disease,including renal,vascular,dental and inflammatory diseases.

关键词： Acacia Senegal chronic renal failure emulsifier gum Arabic natural fiber probiotics solitary kidney

Assessment of ship manoeuvrability by using a coupling between a nonlinear transient manoeuvring model and mathematical programming techniques

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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINE Abdellatif NACEUR Hakim EL WASSIFI karima Laboratoire Roberval Université de Technologie de Compiègne Laboratoire LAMIH Université de Valenciennes Université Cadi Ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

Hourly and monthly variations in the surface activity patterns of Hemilepistus reaumurii in arid environments of Tunisia

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Journal of Arid Land 2018年第3期10卷 470-481页

作者： Anas AYARI Moez TOUIHRI Chedlia GHEMARI karima NASRI-AMMAR Research Unit of Bio-Ecology and Evolutive Systematics Faculty of Sciences of Tunis University of Tunis El Manar

Life in desert ecosystems drives animals to adapt their surface locomotor activity according to environmental conditions. In this study, the hourly and monthly variations in the surface activity patterns of the terrestrial crustacean Hemilepistus reaumurii were investigated. The surface activity of H. reaumurii at the population scale was observed by collecting the hourly active individuals from the sunrise to the sunset of the studied day in each month of 2013 in the Bchachma locality, Tunisia. The collected active individuals were put in perspex boxes（on which we labeled the hourly time interval in which the individuals were collected） in the field and then transported to the laboratory for analysis. Individuals were counted, sexed, and measured in the laboratory. Despite desert conditions in the studied site, H. reaumurii was characterized by a diurnal surface activity, showing a bimodal pattern during the warm months（i.e., May to October）. However, it exhibited a unimodal surface activity pattern in the cold months（i.e., February, March, and November）. The surface activity was significantly correlated with sunrise and sunset. Moreover, a significant quadratic effect of temperature on the surface activity of H. reaumurii was observed. Furthermore, the study showed that the most important surface activity was recorded in March. The daily exploitation of the temporal niches was significantly different as a function of months. The body size of males was larger than that of females, and the body size of active individuals changed with months. All these behavioural changes in the surface activity represent an adaptive strategy of life in the arid environment.

关键词： diurnal activity variation pattern aboveground activity desert isopod temporal niche Hemilepistus reaumurii Tunisia

Immunobiodiversity:Conserved and specific immunity across land plants and beyond

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Molecular Plant 2024年第1期17卷 92-111页

作者： Baptiste Castel karima El Mahboubi Christophe Jacquet Pierre-Marc Delaux Laboratoire de Recherche en Sciences Végétales(LRSV) Universitéde ToulouseCNRSUPSToulouse INPCastanet-TolosanFrance

Angiosperms represent most plants that humans cultivate,grow,and ***,angiosperms are only one of five major land plant *** a whole lineage,plants also include algal *** these clades represent a tremendous genetic diversity that can be investigated to reveal the evolutionary history of any given *** this review,we describe the current model of the plant immune system,discuss its evolution based on the recent literature,and propose future directions for the *** angiosperms,plant–microbe interactions have been intensively studied,revealing essential cell surface and intracellular immune receptors,as well as metabolic and hormonal defense *** diversity at the genomic and functional levels demonstrates the conservation of these pathways across land plants,some of which are beyond *** basis of the conserved mechanisms,lineage-specific variations have occurred,leading to diversified reservoirs of immune *** rare cases,this diversity has been harnessed and successfully transferred to other species by integration of wild immune receptors or engineering of novel forms of receptors for improved resistance to *** propose that exploring further the diversity of immune mechanisms in the whole plant lineage will reveal completely novel sources of resistance to be deployed in crops.

关键词： evolution MPMI immunity plant evoMPMI symbiosis

Effects of process parameters on nonaqueous gelcasting for copper powder

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 542-547页

作者： karima Bekouche Zhao-li Wang Cheng-Chang Jia Bo-wen Liu Yi Tang Institute of Advanced Materials and Technology University of Science and Technology Beijing

An approach to fabricate sintered copper with high green strength and high sintered density using nonaqueous gelcasting technol- ogy is presented in this study. The effects of various gelcasting processing parameters such as monomer content, monomer/crosslinker ratio, initiator content, dispersant dosage, and temperature on the flexural strength of dried green bodies and the relative density of sintered bodies were studied to obtain better microstructures and properties. The appropriate process parameters obtained for copper gelcasting are as follows monomer content, 20vol%-30vol% （based on the total volume of reagents）; monomer/crosslinker ratio, 10：1 to 20：1; initiator content, 3vol%-4vol% （based on the volume of the monomer）; dispersant dosage, 1.5wt%-2.5wt% （based on the mass of the copper powder）; and reaction temperature, 65-75℃.

关键词： copper powder gelcasting monomer process parameters flexural strength density