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Structural integrity evaluation of irradiated LEU targets for the production of molybdenum‑99 using thermo‑mechanical behavior simulation coupled with pressure of fission gas release calculation

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Nuclear Science and Techniques 2022年第12期33卷 12-23页

作者： N.mellel B.mohammedi m.salhi m.Dougdag S.missaoui S.Hanini Birine Nuclear Research Center PB 18017200 Ain OusseraDjelfaAlgeria LBmPT UniversitéDr Yahia Farès 26000 MédéaAlgeria

Irradiated low-enriched uranium as target plates is used to produce,via neutron radiation and from the molybdenum-99 fission product,technetium-99m,which is a radio-element widely used for diagnosis in the field of nuclear *** behavior of this type of target must be known to prevent eventual failures during *** present study aims to assess,via prediction,the thermal–mechanical behavior,physical integrity,and geometric stability of targets under neutron radiation in a nuclear *** this purpose,a numerical simulation using a three-dimensional finite element analysis model was performed to determine the thermal expansion and stress distribution in the target *** neutronic calculation results,target material properties,and cooling parameters of the KAERI research group were used as inputs in our developed *** induced stress and deflection on the target were calculated using Ansys-Fluent codes,and the temperature profiles,as inputs of this calculation,were obtained from a CFD thermal–hydraulic *** stress generated,induced by the pressure of fission gas release at the interface of the cladding target,was also estimated using the Redlich–Kwong equation of *** results obtained using the bonded and unbonded target models considering the effect of the radiation heat combined with a fission gas release rate of approximately 3%show that the predicted thermal stress and deflection values satisfy the structural performance requirement and safety *** can be presumed that the integrity of the target cladding is maintained under these conditions.

关键词： Irradiated LEU target mo-99 production Integrity evaluation Thermo-mechanical analyses Fission gas pressure

Conceptual design of irradiation device for silicon neutron transmutation doping around Es-Salam research reactor

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Nuclear Science and Techniques 2020年第4期31卷 69-78页

作者： m.salhi B.mohammedi S.Laouar m.Dougdag m.Touiza m.Abbaci m.moughari Centre de Recherche Nucle′aire de Birine 17200 Ain OusseraAlgeria Institut Alge′rien de formation en Ge′nie Nucle′aire 16050 DrariaAlgerAlge′rie

Silicon neutron transmutation doping remains one of the most viable nuclear applications for research *** this kind of product involves an irradiation method capable of fulfilling the quality requirements of doping and alleviating the challenges related to the design and safety of the irradiation *** this paper,we propose an irradiation device prototype for neutron transmutation doping of silicon ingots with diameters of 2 to 3 *** on the Es-Salam research *** thermal hydraulic analysis of the proposed irradiation device was performed to determine the optimum conditions for *** effect of the mechanical vibrations induced by the circulation of coolant in the device was quantified via experimental measurements under different flow *** results show that the maximum temperature reached by the silicon ingots is below the temperature limit,effectively validating the design of the irradiation *** investigations are prospected to further optimize the design and the irradiation *** irradiation of silicon ingots with a large diameter will be considered.

关键词： Irradiation device prototype Es-Salam research reactor NTD-Si Irradiation temperature CFD method

Cooling enhancement of planar-balanced magnetron cathode

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Nuclear Science and Techniques 2017年第8期28卷 69-74页

作者： m'hamed salhi Seddik El Hak Abaidia Brahim mohamedi Sofiane Laouar Centre de Recherche Nucleaire de Birine B.P. 18017200 Ain-Oussera Algeria Unite de Recherche mPE Faculte des Sciences de l'Ingenieur Universite M'hamed Bougarra de Boumerdes 35000 Boumerdes Algeria

In physical vapor deposition on a magnetron cathode, temperature of sensitive components must be kept under threshold limit, so as to ensure the cathode reliability,the process reproducibility, and the best quality of thin *** can be achieved by an adequate design to enhance the dissipation of heat generated at the cathode. In this paper,temperature distribution and streamlines velocity of the cathode coolant inside a cathode magnetron are analyzed by using CFD solver ANSYS FLUENT in the single-phase method in combination with k–e standards turbulent *** results show that the design is appropriate under the calculation parameters, and for high heat densities some improvements are necessary to enhance heat dissipation and keep temperature under the threshold limit.

关键词：阴极冷却强化磁控平衡平面物理气相沉积 FLUENT 温度分布

Oxidation of propane over substituted Keggin phosphomolybdate salts

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Journal of Natural Gas Chemistry 2009年第3期18卷 319-324页

作者： T.mazari C.Roch.marchal S.Hocine N.salhi C.Rabia Laboratoire de Chimie du Gaz Naturel Faculté de ChimieUniversité des Sciences et de la Technologie Houari Boumediéne ILV-UmR 8180 CNRS-Université de Versailles-St Quentin-en-Yvelines Batiment Lavoisier45 avenue des Etats-Unis78035 Versailles CedexFrance

Ammonium salts, （NH4）6HPmo11mO40 （m = Ni, Co, Fe）, have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9 ℃/min. They were characterized by BET method, XRD, 31p NmR, UV-Vis and IR techniques. The catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 ℃/min.

关键词： propane oxidation propene acrolein polyoxometalates phosphomolybdate

Precipitation in Ni-35 at. pct Cr Alloy

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Journal of materials Science & Technology 2002年第1期18卷 77-79页

作者： A.A.Al-Aql, m.S.Al-salhi and m.I.AnsariPhysics Department, Faculty of Science, King Saud University, Riyadh 11451, Saudi Arabia [ manuscript received February 7, 2001, in revised form may 10, 2001] Dept. of Phys. Faculty of Sci. King Saud Univ. Riyadh 11451 Saudi Arabia

Precipitation study was carried out in Ni-35 at. pct Cr alloy by measuring electrical resistivity at different ageing temperatures and long ageing times. During ageing, it was observed that electrical resistivity initially rose with ageing time and then fell after very long ageing at a constant temperature. The initial increase in resistivity during ageing may be attributed to the formation of GP zones/Cr-rich precipitates at early stages by nucleation process and decrease in resistivity, and after attaining a maximum, is due to the growth of precipitate particles and subsequently by coarsening of these precipitates. The results of electrical resistivity measurements during ageing were confirmed by X-ray diffraction analysis indicating the formation of a Cr-rich phase and a Cr3Ni2 phase in the Ni matrix.

关键词： Precipitation Electrical resistivity Ageing Coarsening X-ray diffraction

Oxidation of propane over ammonium-transition metal mixed keggin phosphomolybdate salts

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Journal of Natural Gas Chemistry 2010年第1期19卷 54-60页

作者： T. mazari C. Roch. marchal S. Hocine N. salhi C. Rabia Laboratoire de Chimie du Gaz Naturel Faculte' de Chimie Universite' des Sciences et de la Technologie Houari Boumedie`ne USTHB BP32 El-Alia Bab-Ezzouar Alger Alge'rie ILV-UmR 8180 CNRS Universite' de Versailles -St Quentin-en-Yvelines Ba?timent Lavoisier 45 avenue des Etats-Unis 78035 Versailles Cedex France

mixed ammonium-transition metal salts with formula of （NH4）xmyHzPmo12O40 （m = Ni^2＋, Co^2＋ or Fe ^3＋） denoted as mPmo12 have been investigated for the oxidation of propane, with molecular oxygen, at temperature range between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9℃/min. They were characterized by BET method, XRD, UV-Vis and IR techniques. The catalysts were found to be active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9℃/min. FePmo12 was found to be a more active catalyst for propene （17.2% yield） with minimal over deep oxidation （0.3% yield in COx）.

关键词： phosphomolybdate ammonium keggin propane oxidation propene acrolein

The Allelochemicals Effect of Zygophyllum album on Control of Bromus tectorum

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Journal of Life Sciences 2012年第2期6卷 182-186页

作者： salhi Nesrine Salama m. El-Darier Halilat m. Taher Laboratory for Bioressources Saharan Preservation and Enhancement University ofKasdi Merbah Ouargla 30000 Algeria Departments of Botany Faculty of Science University of Alexandria Alexandria 21545 Egypt

The aim of the present study was to investigate the potential allelopathic effects of different concentrations of Zygophyllum album （donor species） aqueous extract （2.5, 5, 7.5 and 10%） on germination percentage, plumule and radicle length ofBromus tectorum （weed） and Triticum aestivum （crop species） under laboratory conditions to have the greatest inhibitory allelopathic effect on the recipient species in mixed culture compared to that pure culture. The germination percentage, plumule and radicle length ofB. tectorum in mixed culture was completely inhibited at the highest concentration of aqueous extracts of the donor species level the exerted weak measures as affected by the highest concentration level of donor in pure culture. This inhibition was markedly in obvious B. tectorum that is more sensitive to tested donor. The domineering effect of aqueous extract of the donor was more prominent on weeds than crop species. The variant response to the allelopathic substance could be related to the species specific growth regulatory effect of allelochemicals and concentration dependent. There is possibility of using these allelochemicals directly or as structural leads for the discovery and development of environment friendly herbicides to control weeds.

关键词： Allelopathy germination Zygophyllum album Bromus tectorum Triticum aestivum.

Waveguide Design Optimization for Long Wavelength Semiconductor Lasers with Low Threshold Current and Small Beam Divergence

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Journal of modern Physics 2011年第4期2卷 225-230页

作者： Abdulrahman Al-muhanna Abdullah Alharbi Abdelmajid salhi 不详

Long wavelength GaSb-based quantum well lasers have been optimized for high coupling efficiency into an optical system. Two approaches were used to reduce the vertical far-field. In the first approach we showed the use of V-shaped Weaker Waveguide in the n-cladding layer dramatically reduces vertical beam divergence without any performance degradation compared to a conventional broad-waveguide laser structure. Starting from a broad waveguide laser structure design which gives low threshold current and a large vertical far-field (VFF), the structure was modified to decrease the VFF while maintaining a low threshold-current density. In a first step the combination of a narrow optical waveguide and reduced refractive index step between the waveguide and the cladding layers reduce the VFF from 67? to 42?. The threshold current density was kept low to a value of ~190 A/cm2 for 1000 × 100 μm2 devices by careful adjustment of the doping profile in the p-type cladding layer. The insertion of a V-Shaped Weaker Waveguide in the n-cladding layer is shown to allow for further reduction of the VFF to a value as low as 35? for better light-coupling efficiency into an optical system without any degradation of the device performance. In the second approach, we showed that the use of a depressed cladding structure design also allows for the reduction of the VFF while maintaining low the threshold current density (210 A/cm2), slightly higher value compare to the first design.

关键词： Semiconductor Laser Far-Field Simulation

magnetic Studies of Spin Wave Excitations in Ni/Cu multilayers

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Journal of modern Physics 2011年第11期2卷 1285-1289页

作者： Abdeslam Tizliouine Hayat salhi Hassan Lassri Naima Addou 不详

The magnetic properties of Ni/Cu multilayers, prepared by the electron beam evaporation method under ultra high vacuum conditions, have been systematically studied by magnetic measurements. The temperature dependence of the spontaneous magnetization m (T) is well described by a T3/2 law. A spin wave theory has been used to explain the magnetization versus temperature. Based on this theory, the approximate values for the exchange interactions have been obtained.

关键词： Ni/Cu multilayer magnetization Spin Wave Excitations Exchange Interactions