The crystalline zeolite, namely faujasite type Y with SiO2/Al2O3 mole ratio of 5 was used as raw material for preparation of isomerization catalysts. A 0.5 wt % Pt/HY-zeolite catalyst was prepared by impregnation of the decationized HY-zeolite with chloroplatinic acid. The dectionized HY-zeolite was treated with HCl, HNO3 and HI promoters using different normalities and with different concentrations of Sn, Ni and Ti promoters by impregnation method to obtain acidic and metallic promoters' catalysts, respectively. A 0.5 wt% of Pt was added to above catalysts using impregnation method. Isomerization of n-hexane was carried out at different prepared catalysts. The isomerization temperature varied from 250–325° C over weight hourly space velocity (WHSV) 1.6 h-1. The pressure and hydrogen to feed mole ratio were kept constant at 1bar and 2 mol/mol, respectively. The comparison between the above prepared catalysts shows that the total isomer yield during the process with Sn-Pt /HY- zeolite catalyst was higher than the other catalysts and, reached to 63.95% vol. A 0.5 wt% of W and Zr was added to Sn-Pt/HY-zeolite catalyst by impregnation method to obtain W and Zr co-metal promoters catalysts. Isomerization of n-hexane was investigated using W and Zr co-metal promoters catalyst at the same operating conditions and the yield of isomers reached to 81.14% vol.and 79.07%vol.,respectively.
The photoconductivity and its dependence on light intensity have been investigated in a-Ge20Se80 thin films as a function of temperature between (293–323)K. The result showed that the photoconductivity and photosensitivity increase with increase of annealing temperature. This behavior is interpreted in terms of the dispersive diffusion –controlled recombination of localized electrons and holes.
This study has sought to explore the Yemeni online news websites’ treatment of the tropical storm “Luban” which hit the coasts of al-Mahra governorate, and other parts of the Yemeni Eastern and Southern governorates in October 2018. The study also examined how the Yemeni news websites covered the disaster on the basis of the problematic situation model. The study’s findings revealed a form of logical balance in distributing the coverage of the disaster in its different phases. The coverage was a bit more focused on the disaster phase than the pre- and post-disaster phases. Additionally, the websites paid more attention to precautionary measures and the disaster’s humanitarian and material losses. The findings reveal that the ne
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The rapid success and the field dilation of Daish organization in both Iraq and Syria make academic institutes and research centers to pay attention to its propaganda means to gain its public opinion, and to further investigation about new methods employed by this organization to disseminate its messages to the public, particularly young people in large areas of the world. This organization uses traditional propaganda techniques on psychological war and its levels, social network sites and platforms that are distributed online. This study seeks to expose more persuasive methods used by the organization to gain multiple classes of society and to disseminate its extremist ideological thoughts. It also studies the psychological operation an
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The Lamiaceae L. family grows and widely distributed in Iraq. The study aimed to enumerate the species that has been preserved in several botanical herbariums: National Herbarium of Iraq- Ministry of Agriculture (BAG), University of Baghdad Herbarium (BUH), Iraq Natural History Research Center& Museum- University of Baghdad Herbarium (BUNH), College of Agricultural Engineering- University of Baghdad Herbarium (BUG), College of Agricultural Engineering Sciences- Duhok Province University Herbarium (DPUH) and College of Science - Salahddin University Herbarium (SUH). This family has not yet been registered in the Flora of Iraq. After examining more than 1000 herbarium specimens, the study found 139 species belonging to 33 genera h
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Background: zirconium (Zr) implants are known for having an aesthetically pleasing tooth-like colour Unlike the grey cervical collar that develops over time when titanium (Ti) implants are used in thin gingival biotypes. However, the surface qualities of Zr implants can be further improved. This present study examined using thermal vapour deposition (TVD) to coat Zr implants with germanium (Ge) to improve its physical and chemical characteristics and enhance soft and hard tissue responses. Materials and methods: Zr discs were divided into two groups; the uncoated (control) group was only grit-blasted with alumina particles while the coated (experimental) group was grit-blasted then coated with Ge via TVD. Field emission scanning ele
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This Research Tries To Investigate The Problem Of Estimating The Reliability Of Two Parameter Weibull Distribution,By Using Maximum Likelihood Method, And White Method. The Comparison Is done Through Simulation Process Depending On Three Choices Of Models (?=0.8 , ß=0.9) , (?=1.2 , ß=1.5) and (?=2.5 , ß=2). And Sample Size n=10 , 70, 150 We Use the Statistical Criterion Based On the Mean Square Error (MSE) For Comparison Amongst The Methods.
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Academic Buoyancy of High School students at the Distinguished Schools
شهد العالم مع بداية القرن الحادي والعشرين تدشين مرحلة جديدة من التطور شملت مختلف الميادين لاسيما في مجال التطورات العلمية والثورة المعلوماتية.. كما إن مسار الديمقراطية في بعض دول العالم يصبح سالكا خاصة في تركيا, فمنذ اواسط الثمانينيات من القرن الماضي فتح المجال السياسي امام قوى كانت مسحوقة ومهمشة, ويكاد ان لا يكون لها وجود في الحياة السياسية للنزول الى ساحة العمل السياسي اسوة ببقية القوى ا
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One of the costliest problems facing the production of hydrocarbons in unconsolidated sandstone reservoirs is the production of sand once hydrocarbon production starts. The sanding start prediction model is very important to decide on sand control in the future, including whether or when sand control should be used. This research developed an easy-to-use Computer program to determine the beginning of sanding sites in the driven area. The model is based on estimating the critical pressure drop that occurs when sand is onset to produced. The outcomes have been drawn as a function of the free sand production with the critical flow rates for reservoir pressure decline. The results show that the pressure drawdown required to
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