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Further Studies of BURSTS and Spallation in High-Energy Heavy Ion Reactions

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World Journal of Nuclear Science and Technology 2017年第1期7卷 35-57页

作者： reza hashemi-nezhad Reinhard Brandt Valery Ditlov Maria Haiduc Elena Firu Alina Tania Neagu Eberhard Ganssauge Wolfram Westmeier School of Physics University of Sydney Sydney Australia Kernchemie FB Chemie Philipps Universit&#228 t Marburg Marburg Germany Institute of Theoretical and Experimental Physics Moscow Russia Bucharest Institute of Space Science Bucharest Romania FB Physik Philipps Universit&#228 t Marburg Marburg Germany Dr. Westmeier GmbH Ebsdorfergrund Germany

Aspects of BURSTS and Spallation reactions induced by high-energy heavy ions in thick targets (>10 cm thick) will be investigated: BURSTS are reviewed from a historical and phenomenological point-of-view. Details of interactions in nuclear emulsions will be compared for irradiations of 72 GeV 22Ne-ions from Dubna with irradiations of 72 GeV 40Ar-ions from Berkeley. Measured correlations in individual interactions between multiplicities of “minimum ionizing particles”, ns, and “black prongs”, nb, will be shown as “ns-vs.-nb” per event for BURSTS and separately for Spallation in interactions of 72 GeV 22Ne-ions. Monte Carlo calculations, based on the MCNPX 2.7 code, have been carried out for 72 GeV 22Ne interacting in nuclear emulsions: The correlation between ns and nb in Spallation reactions could be understood. However, “ns-vs.-nb” correlations from BURST-interactions could not be reproduced with this model for events with small numbers of heavy prongs nh ≤ 10. For large numbers of heavy prongs with nh > 10 one could find some agreement between experiments and calculations, however, not in all details. Further experimental and theoretical studies are necessary before one has a complete understanding of BURST interactions in high-energy heavy ion reactions.

关键词： High-Energy HI Reaction BURST Spallation MCNPX

Two Ways of High-Energy Heavy Ion Interactions: Spallation and Burst

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World Journal of Nuclear Science and Technology 2015年第2期5卷 73-87页

作者： Reinhard Brandt Valery Ditlov Maria Haiduc Elena Firu Alina Tania Neagu Eberhard Ganssauge reza hashemi-nezhad Wolfram Westmeier Kernchemie FB Chemie Philipps-Universitat Marburg Marburg Germany Alikhanov Institute of Theoretical and Experimental Physics Moscow Russia Bucharest Institute of Space Sciences Bucharest Romania Fachbereich Physik Philipps-Universitat Marburg Marburg Germany School of Physics University of Sydney Sydney Australia Dr. Westmeier GmbH Ebsdorfergrund Germany

A new approach to solving the observation of enhanced neutron production in high-energy heavy ion induced reactions in thick targets is presented. Two different reaction mechanisms in these interactions are considered: 1) Limited fragmentation of the projectile, called SPALLATION;2) Complete nuclear fragmentation of the projectile fragment into individual relativistic hadrons only, referred to as “BURST”. The abundance of this second path increases with the charge and energy of the projectile and may be responsible for enhanced neutron production observed with radiochemical methods in 44 GeV 12C and 72 GeV 40Ar irradiations. Interactions of 72 GeV 22Ne in nuclear emulsions show that SPALLATION and BURST have strongly different interaction signatures, and also that the rate of BURSTS increases from (26 ± 3)% of all interactions in the 1st generation to (78 ± 6)% in the 2nd generation. Further experimental signatures of BURSTS will be described;however, no model based on physics concepts can be presented. This effect may have practical consequences for neutron safety considerations in the construction of advanced heavy ion accelerators.

关键词： Thick Target High Energy Projectile Unresolved Problems BURST

Comment on the Recent Start of a New “IUPAC-Project”

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World Journal of Nuclear Science and Technology 2018年第3期8卷 121-127页

作者： Reinhard Brandt Valery Ditlov Elena Firu Eberhard Ganssauge Maria Haiduc reza hashemi-nezhad Alina Tania Neagu Wolfram Westmeier Kernchemie FB Chemie Philipps-Universit&auml t Marburg Marburg Germany Institute of Theoretical and Experimental Physics Moscow Russia Bucharest Institute of Space Science Bucharest Romania FB Physik Philipps-Universit&auml t Marburg Marburg Germany School of Physics The University of Sydney Sydney Australia Dr. Westmeier GmbH Ebsdorfergrund Germany

The opening of a new IUPAC-project is highly appreciated. In the year 2009, the IUPAC had published an article “Discovery of the element with atomic number 112 (IUPAC Technical Report)” [1]* which contains a section on the work of the Marinov collaboration. It appears that this section is not always in agreement with conventional standards for scientific publications. This present comment focuses on these formal questions.

关键词： IUPAC Project 2017-014-2-200 eka-Hg Unresolved Problems

Recent advances using equal-channel angular pressing to improve the properties of biodegradable Mg-Zn alloys

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Journal of Magnesium and Alloys 2023年第7期11卷 2260-2284页

作者： Mohammad hashemi reza Alizadeh Terence G.Langdon Department of Materials Science and Engineering Sharif University of TechnologyTehranIran Materials Research Group Department of Mechanical EngineeringUniversity of SouthamptonSouthampton SO171BJUnited Kingdom

Magnesium alloys are of considerable current interest for use as degradable implants due to their unique properties including biodegrad-ability,biocompatibility,low density and adequate mechanical ***,there is a need to further improve these properties either by alloying or through the use of appropriate *** the different biodegradable Mg alloys now in use,the Mg-Zn series are of special interest and have been the subject of many research *** is primarily because Zn is an essential element for the human body in addition to its positive effects in improving the mechanical strength and lowering the degradation rate of the *** properties of Mg-Zn alloys may be further improved both through the addition of third and fourth alloying elements such as Ca,Ag,Sn or Sr and/or by thermo-mechanical processing where the latter is more environmentally and economically *** practice,procedures based on the application of severe plastic deformation(SPD)are especially suited to produce fine-grained microstructures with improved mechanical,degradation and cell ***-channel angular pressing(ECAP)is a popular SPD technique that has the capability of pro-ducing bulk materials that are sufficiently large for use as typical ***,this review is designed to provide a comprehensive summary of the research that has been undertaken on ECAP-processed biodegradable Mg-Zn alloys.

关键词： Bio-degradation ECAP Fine-grained microstructure Mg–Zn alloys Severe plastic deformation

A GIS-based time-dependent seismic source modeling of Northern Iran

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 33-45页

作者： Mahdi hashemi Ali Asghar Alesheikh Mohammad reza Zolfaghari School of Information Seiences University of Pittsburgh Pittsburgh Pennsylvania 15260 USA Department of Geospatial Information Systems K.N. Toosi University of Technology Tehran 19697 Iran Civil Engineering Department K.N. Toosi Universiry of Technology Tehran 19697 Iran

： The first step in any seismic hazard study is the definition of seismogenic sources and the estimation of magnitude-frequency relationships for each source. There is as yet no standard methodology for source modeling and many researchers have worked on this topic. This study is an effort to define linear and area seismic sources for Northern Iran. The linear or fault sources are developed based on tectonic features and characteristic earthquakes while the area sources are developed based on spatial distribution of small to moderate earthquakes. Time-dependent recurrence relationships are developed for fault sources using renewal approach while time-independent frequency-magnitude relationships are proposed for area sources based on Poisson process. GIS functionalities are used in this study to introduce and incorporate spatial- temporal and geostatistical indices in delineating area seismic sources. The proposed methodology is used to model seismic sources for an area of about 500 by 400 square kilometers around Tehran. Previous researches and reports are studied to compile an earthquake/fault catalog that is as complete as possible. All events are transformed to uniform magnitude scale; duplicate events and dependent shocks are removed. Completeness and time distribution of the compiled catalog is taken into account. The proposed area and linear seismic sources in conjunction with defined recurrence relationships can be used to develop time-dependent probabilistic seismic hazard analysis of Northern Iran.

关键词： seismic source modeling geostatistical index seismic hazard GIS

Enhanced oil recovery from carbonate reservoirs by spontaneous imbibition of low salinity water

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Petroleum Science 2018年第3期15卷 564-576页

作者： Mohammad reza Zaeri Rohallah hashemi Hamidreza Shahverdi Mehdi Sadeghi Department of Chemical Engineering Isfahan University of Technology

An experimental study was performed to investigate the impact of low salinity water on wettability alteration in carbonate core samples from southern Iranian reservoirs by spontaneous imbibition. In this paper, the effect of temperature, salinity,permeability and connate water were investigated by comparing the produced hydrocarbon curves. Contact angle measurements were taken to confirm the alteration of surface wettability of porous media. Oil recovery was enhanced by increasing the dilution ratio of sea water, and there existed an optimum dilution ratio at which the highest oil recovery was achieved. In addition, temperature had a very significant impact on oil recovery from carbonate rocks. Furthermore, oil recovery from a spontaneous imbibition process was directly proportional to the permeability of the core samples. The presence of connate water saturation inside the porous media facilitated oil production significantly. Also, the oil recovery from porous media was highly dependent on ion repulsion/attraction activity of the rock surface which directly impacts on the wettability conditions. Finally, the highest ion attraction percentage was measured for sodium while there was no significant change in pH for all experiments.

关键词： Enhanced oil recovery Spontaneous imbibition Low salinity water Wettability alteration Carbonate rocks

A green and efficient oxidation of benzylic alcohols using H_2O_2 catalyzed by montmorillonite K-10 supported CoCl_2

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Chinese Chemical Letters 2008年第11期19卷 1277-1280页

作者： Ali Ezabadi Ghloam reza Najafi Mohammad M.hashemi Department of Chemistry Central Tehran BranchAzad UniversityTehranIran Department of Chemistry Science & Research BranchAzad UniversityTehranIran

Primary and secondary benzylic alcohols were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H2O2 catalyzed by montmorillonite K-10 supported cob... 详细信息

关键词： Grecn oxidation Hydrogcn peroxide Montmorillonite K-10 Cobalt(Ⅱ) chloride

A green and efficient deoximation using H_2O_2 catalyzed by montmorillonite-K10 supported CoCl_2

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Chinese Chemical Letters 2007年第12期18卷 1451-1454页

作者： Ali Ezabadi Gholam reza Najafi Mohammed M.hashemi Department of Chemistry Central Tehran Branch Department of Chemistry Science and Research BranchIslamic Azad UniversityTehranIran Department of Chemistry Sharif University of TechnologyP.O.Box 11365-9516TehranIran

Oximes were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H202 catalyzed by montmorillonite K-10 supported cobalt（Ⅱ） chloride.

关键词： Green deoximation system Hydrogen peroxide Montmorillonite K-IO Cobalt(II) chloride

MgO Nanoparticles as a Recyclable Heterogeneous Catalyst for the Synthesis of Polyhydroquinoline Derivatives under Solvent Free Conditions

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Chinese Journal of Chemistry 2011年第8期29卷 1624-1628页

作者： Ranjbar-Karimi, reza hashemi-Uderji, Somayeh Bazmandegan-Shamili, Alireza Department of Chemistry Faculty of Science Vali-E-Asr University Rafsanjan Islamic Republic of lran PO BOX 77176 lran

Magnesium oxide nanopartticels in average size between 35--120 nm were prepared by sonochemistry method. Synthesis of polyhydroquinoline derivatives using MgO nanoparticles from the reaction of dimedone, benzaldehyde ethyl acetoacetate and ammonium acetate under solvent-free conditions is reported. Easy handling, reusability, thermal stability and non-toxicity of the catalyst make the present protocol as an eco-friendly and economically acceptable method for synthesis of these heterocycles.

关键词： multicomponent reaction cyclization nanoparticle magnesium oxide polyhydroquinoline dihydropyridines aldehyde