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Experimental Study on Deoxidization of Bariumand Barium Alloy

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Journal of Materials Science & Technology 1999年第5期15卷 400-404页

作者： Shi, YF Chen, BP Fu, J el gammal, T Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China Rhein Westfal TH Aachen Inst Eisenhuttenkunde Aachen Germany

Based on the review of latest papers related to the application of barium alloy, the deoxidization effects of barium and barium alloy, and the dynamic characteristics of molten bath have been systematically studied by means of the convection free bath, natural convection bath, air and vacuum induction melting experiments. It was found that both the total oxygen content and soluble oxygen content in molten bath decreased rapidly. The results obtained provided practical and theoretical basis for further synthetic applications of barium alloy in metallurgical industry.

关键词： Barium

Effect of sintering temperature on microstructure and electrical properties of Sr_(1-x)(Na_(0.5)Bi_(0.5))_(x)Bi_(2)Nb_(2)O_(9) solid solutions

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Journal of Advanced Ceramics 2014年第1期3卷 17-30页

作者： Hana NACEUR adel MEGRICHE Mohamed el MAAOUI Laboratory of Applied Mineral Chemistry Department of ChemistryFaculty of SciencesUniversity Tunis ElManarCampus 2092TunisTunisia

In this study,we investigated the effect of sintering temperature on densification,grain size,conductivity and dielectric properties of Sr_(1-x)(Na_(0.5)Bi_(0.5))_(x)Bi_(2)Nb_(2)O_(9) ceramics,prepared by hydrothermal *** were sintered at different *** increased with sintering temperature,reaching up to 96%at 800℃.A grain growth was observed with increasing sintering *** spectroscopy analyses of the sintered samples at various temperatures were *** in dielectric constant and in Curie temperature with sintering was *** conductivity and activation energy were calculated and attributed to the microstructural factors.

关键词： ceramics sintering light scattering dielectric properties

The Rain on Underground Porous Media Part Ⅰ:Analysis of a Richards Model

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Chinese Annals of Mathematics,Series B 2013年第2期34卷 193-212页

作者： Christine BERNARDI adel BLOUZA Linda el ALAOUI Laboratoire Jacques-Louis Lions CNRS & Université Pierre et Marie CurieBC 1874 Place Jussieu75252 Paris Cedex 05France Laboratoire de Mathématiques Raphaёl Salem(UMR 6085 CNRS) Université de RouenAvenue de l'UniversitéBP 1276801 Saint-tienne-du-RouvrayFrance Universit Paris 13 Sorbonne Paris CitLAGACNRS(UMR 7539)F-93430VilletaneuseFrance

The Richards equation models the water flow in a partially saturated underground porous medium under the *** it rains on the surface,boundary conditions of Signorini type must be considered on this part of the *** authors first study this problem which results into a variational inequality and then propose a discretization by an implicit Euler's scheme in time and finite elements in *** convergence of this discretization leads to the well-posedness of the problem.

关键词： Richards equation, Porous media, Euler's implicit scheme, Finite element discretization Parabolic variational inequality

Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

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Acta Geochimica 2024年第1期43卷 150-173页

作者： adel A.Surour Ahmed A.Madani Mohamed A.el-Sobky Faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

In the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal el Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the Alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)O_(2),Al_(2)O_(3),alkalis,lithosphile elements(LILEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range elieved that the Gabal Batuga felsic intrusion started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal el Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

Dynamics of CO_2 Emission and Biochemical Properties of a Sandy Calcareous Soil Amended with Conocarpus Waste and Biochar

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Pedosphere 2015年第1期25卷 46-56页

作者： Mohamed el-MAHROUKY Ahmed Hamdy el-NAGGAR adel Rabie USMAN Mohammad Al-WABel Soil Science Department College of Food & Agriculture Sciences King Saud University Department of Soil Science Faculty of Agriculture Ain Shams University Department of Soils and Water Faculty of Agriculture Assiut University

Biochar is a carbon-rich product obtained by biomass pyrolysis and considered a mean of carbon sequestration. In this research, a sandy calcareous soil from the Farm of the College of Food & Agriculture Sciences, King Saud University, Saudi Arabia, was amended with either woody waste of Conocarpus erectus L.(CW) or the biochar(BC) produced from CW at rates of 0(control), 10, 30 and 50 g kg-1. The effects of the amendments on soil p H, dissolved organic carbon(DOC), microbial biomass carbon(MBC), CO2 emission and metabolic quotient(q CO2) of the sandy calcareous soil were studied in a 60-d incubation experiment. The results showed that the addition of CW led to a significant decrease in soil p H compared to the control and the addition of BC. The CO2-C emission rate was higher in the first few days of incubation than when the incubation time progressed. The cumulative CO2-C emission from the soil amended with CW, especially at higher rates, was higher(approximately 3- to 6-fold) than that from the control and the soil amended with BC. The BC-amended soil showed significant increases in CO2-C emission rate during the first days of incubation as compared to the non-amended soil, but the increase in cumulative CO2-C emission was not significant after 60 d of incubation. On the other hand, CW applications resulted in considerably higher cumulative CO2-C emission, MBC and DOC than the control and BC applications. With the exception of 0 day(after 1 h of incubation), both CW and BC applications led to lower values of q CO2 as compared to the control. The power function kinetic model satisfactorily described the cumulative CO2-C emission. Generally, the lowest values of CO2 emission were observed in the soil with BC, suggesting that the contribution of BC to CO2 emission was very small as compared to that of CW.

关键词： dissolved organic carbon metabolic quotient microbial biomass carbon power function kinetic model soil pH

Mineralogical and geochemical characterization of the Wadi Natash volcanic field(WNVF),Egypt:Alkaline magmatism in a Late Cretaceous continental rift system

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Acta Geochimica 2024年第6期43卷 1169-1191页

作者： adel A.Surour Ahmed A.Madani Mohamed A.el-Sharkawi Department of Geological Sciences Faculty of ScienceGalala UniversityNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

The Wadi Natash volcanic field(WNVF)in the south of the Eastern Desert of Egypt is a typical example of well-preserved intraplate alkaline magmatism during the Late Cretaceous,i.e.,prior to the Oligo-Miocene Red Sea *** compiled stratigraphic sections at two sectors;namely East Gabal Nuqra and West Khashm Natash(WKN)where the volcanic flows are intercalated with the Turonian Abu Agag sandstone with occasional paleosols when volcanic activity is *** mantle xenoliths are encountered in the first sector whereas flows in the second sector are interrupted by trachyte plugs and ring *** a geochemical basis,the maifc melt originating from the lithospheric mantle beneath the WNVF practiced~5%partial melting of phlogopite-bearing garnet *** dominate in the two sectors and highly evolved(silicic)rocks are confined to the WKN *** of ancient Precambrian fractures following the NW-SE and ENE-WSW trends facilitated the ascend of Late Cretaceous mantle-derived alkaline ***,the WNVF developed at the eastern shoulder of the so-called"Kom Ombo-Nuqra-Kharit rift system"that represents a well-defined NW-trending intracontinental rift basin in the southern Eastern *** such a structural setup,the Natash volcanic are confined to half-grabens at the East Gabal Nuqra sector whereas the West Khashm Natash sector is subjected to extensional stresses that propagated *** WNVF is a typical example of fluvial clastics(Turonian)intercalation with rift-related alkaline volcanic rocks in northeast Africa.

关键词： Wadi Natash volcanic field Late Cretaceous Lithostratigraphy Intraplate rift Abu Agag sandstone Clastic facies

Hidden attractors in a new fractional-order discrete system: Chaos, complexity, entropy, and control

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Chinese Physics B 2020年第5期29卷 174-181页

作者： adel Ouannas Amina Aicha Khennaoui Shaher Momani Viet-Thanh Pham Reyad el-Khazali Laboratory of Mathematics Informatics and Systems(LAMIS)University of Laarbi TebessiTebessa12002Algeria College of Humanities and Sciences Ajman UniversityAjmanUAE Laboratory of Dynamical Systems and Control University of Larbi Ben M’hidiOum El BouaghiAlgeria Department of Mathematics Faculty of ScienceUniversity of JordanAmman 11942Jordan Nonlinear Systems and Applications Faculty of Electrical and Electronics EngineeringTon Duc Thang UniversityHo Chi Minh CityVietnam ECCE Department Khalifa UniversityAbu-Dhabi 127788United Arab Emirates

This paper studies the dynamics of a new fractional-order discrete system based on the Caputo-like difference *** is the first study to explore a three-dimensional fractional-order discrete chaotic system without *** phase portrait,bifurcation diagrams,and largest Lyapunov exponents,it is shown that the proposed fractional-order discrete system exhibits a range of different dynamical ***,different tests are used to confirm the existence of chaos,such as 0-1 test and C0 *** addition,the quantification of the level of chaos in the new fractional-order discrete system is measured by the approximate entropy ***,based on the fractional linearization method,a one-dimensional controller to stabilize the new system is *** results are presented to validate the findings of the paper.

关键词： discrete chaos discrete fractional calculus hidden attractor

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用等离子旋转电极工艺生产高氮钢

钢铁研究学报 2004年第1期16卷 15-20页

作者：陶宇 Tarek el gammal 钢铁研究总院高温材料研究所北京100081 亚琛工业大学钢铁冶金研究所德国亚琛52072

为了寻求高效、经济的高氮钢生产工艺,用等离子旋转电极工艺(PREP)生产高氮钢并测试了所生产的几种典型高氮钢的性能。结果表明,氮可显著地提高奥氏体不锈钢1 4301的室温及高温强度;氮可以提高马氏体不锈钢的强度。为保证高氮马氏体不... 详细信息

为了寻求高效、经济的高氮钢生产工艺,用等离子旋转电极工艺(PREP)生产高氮钢并测试了所生产的几种典型高氮钢的性能。结果表明,氮可显著地提高奥氏体不锈钢1 4301的室温及高温强度;氮可以提高马氏体不锈钢的强度。为保证高氮马氏体不锈钢的淬透性,应根据氮含量适当降低其碳含量或提高铬含量。对于铬含量为17%的马氏体不锈钢1 4122,其碳和氮的总含量不应超过0 65%;当氮含量达到0 24%时,铁素体不锈钢1 4016转变成为马氏体钢,其强度高于碳和氮的总含量与其相当的普通马氏体不锈钢1 4122。

关键词：等离子旋转电极工艺高氮钢粉末冶金生产工艺

Laboratory Investigation of Zinc Recovery fromEAF Dust by Bath Smelting Reduction

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 18-23页

作者： Weiqing Chen Tarek el gammal Metallurgy School, University of Science & Technology Beijing, Beijing 100083, China Institute for Ferrous Metallurgy, Aachen University of Technology, Germany Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China Aachen Univ Technol Inst Ferrous Met Aachen Germany

Bath smelting reduction for recovering zinc from EAF (electric Arc Furnace) dust has been investigated in the laboratory. A degree of zinc volatilization of more than 99% was obtained from the process. Temperature has a clear influence on the reduction rate of ZnO in slag. The reduction rate of (ZnO) by [C] is the first order with respect to the content of ZnO in the slag. The apparent activation energy of the (ZnO) reduction reaction is 312 kJ/mol at 1300-1500℃.

关键词： EAF dust ZnO smelting reduction reduction rate