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Physical Adsorption, Chemical Adsorption, Surface Area, Pore Size distribution, HDS catalyst
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Physical and chemical adsorption analyses were carried out by nitrogen gas using ASTM apparatus at 77 K and hydrogen gas using volumetric apparatus at room temperature respectively. These analyses were used for determination the effect of coke deposition and poisoning metal on surface area, pore size distribution and metal surface area of fresh and spent hydrodesulphurization catalyst Co-MoAl2O3 .Samples of catalyst (fresh and spent) used in this study are taken from AL-Dura refinery. The results of physical adsorption shows that surface area of spent catalyst reduced to third compare with fresh catalyst and these catalysts exhibit behavior of type four according to BET classification ,so, the pores of these samples are cylindrical, and the pores of fresh catalyst suffers during the hydrodesulphurization .The result of chemical adsorption shows that the metal surface area of fresh catalyst is 50.72 m2/g while it reduced to 39.04 m2/g for spent catalyst.

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Publication Date
Sun Jun 30 2013
Journal Name
Al-khwarizmi Engineering Journal
Effect the Grain Size on the Polymer Matrix Composites Reinforced by Reenia Particles
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 Synthetic polymers such as polyurethane are used widely in the field of biomedical applications such as implants or part of implant systems.

This paper focuses on the preparation of base polymer matrix composite materials by (Hand Lay-Up) method, and studying the effect of selected grain size (32, 53, 63, 75, and 90) µm of (Reenia) particles on some properties of the prepared composite.

Mechanical tests were used to evaluate the prepared system (Tensile, Compression, Impact, and Hardness) tests, and a physical test of (Water absorption %), and all tests were accomplished at room temperature.

Where results showed tensile test (maximum tensile strength and modulus of elasticity) high at small grain size while

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Publication Date
Tue Jan 18 2022
Journal Name
Materials Science Forum
The Crystallite Size Dependence of the Transmittance Property of Vanadium Dioxide Nano Films
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Bruggeman's symmetric effective-medium model of vanadium oxide is introduced, in which the transmittance was studied because of its importance in the subject of smart windows, it was studied from ( 5 nm-1000 nm) for each of the regions of the electromagnetic spectrum, the ultraviolet and visible region, and the near and medium sub-regions of the infrared and the results showed that the importance of studying the transmittance of vanadium oxide as a good candidate For this kind of industries. Our results showed that the small sizes of the material guarantee an almost constant and high transmittance to the visible region; this is due to the agreement of the direction of the dipoles in the material with the direction of the internal el

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Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Investigation of Size-dependent Nonlinearity of Ag Nano-Fluids using Self-defocusing Technique
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In this work, the effect of different particle size on the nonlinear optical properties of silver nanoparticles in de-ionized water was studied. The experimental observation of the far field diffraction patterns by CCD camera in two and three dimensions. The maximum change of nonlinear refractive index and the relative phase shift were calculated. The self-defocusing technique was used with a continuous-wave radiation from DPSS Blue laser .The wavelength is 473 nm with an output power of 270 mW. All the Ag colloids samples containing the sizes 15, 30, 50, and 70 nm of silver nanoparticles used in the study were chemically prepared. It was found that the nonlinear refractive index is a particle size dependent and of the order of 10-7 cm2/

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Publication Date
Sun Feb 25 2024
Journal Name
Iraqi Journal Of Agricultural Sciences
ESTIMATING OFF –FARM LABOR SUPPLY AND ANALYSING RELATIONSHIP BETWEEN RISK AND FARM SIZE
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This study was aimed to estimate  off-farm labor supply model.  Data were collected randomly from 267 wheat producers in Salah El-Din province for the year 2020, 67.4% of them are produced using pivot sprinklers for irrigation and with three tenure categories (60,80,12) dunums. Furthermore. The KS coefficient was used to analyze the producers' risk-taking behavior after estimating the production function and determining the area variable that has the most influence on the production process. If it increased by 1%, production would increase by 0.802%. The farmer's decision to adopt the technology was based on economic, social, and institutional factors. It turns out that 40% of farmers make their decision based on financing. When a

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Publication Date
Wed Jun 28 2023
Journal Name
The Iraqi Journal Of Veterinary Medicine
Hematological Parameters as Indicators for Litter size and Pregnancy Stage in Awassi ‎Ewes
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Physiological status and litter size can indeed have a significant impact on ewes' ‎hematological parameters, which are essential indicators of their health. Therefore, this study ‎examined the hematological profiles of ewes during pregnancy with single and twins in the ‎Awassi ewes. The present study involved 232 ewes in good health and at sexual maturity. ‎Among them, 123 ewes had single pregnancies, while 109 ewes had twin pregnancies. The age ‎range of the ewes included in the study was between 3.5 and 4.5 years. Hematological tests ‎were conducted on the sheep's blood samples promptly following collection. The findings ‎demonstrated variations in hematological parameters among pregnant

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Publication Date
Fri Mar 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Study the Catalytic Activity of CeO2 Catalyst for the Oxidative Degradation of Orange G Dye in Aqueous Solution
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The oxidative degradation of Orange G dye by nanosized CeO2 catalyst has been performed in this study. The catalyst was prepared by precipitation method. Various characterization techniques were carried out to study the physical and chemical properties of the synthesized catalyst. The XRD result confirms well the formation of CeO2 cubic phase.  The FTIR result showed the effect of calcination temperature for CeO2 was clearly observed due to reduction in band intensity compared to uncalcined Ce nitrate sample. Meanwhile, the diffused reflection spectra recorded reflection spectra at 414 nm with an energy gap of 3.2 ev. The decolorization of Orange G dye by oxidation process were carried out  unde

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Publication Date
Fri Mar 31 2017
Journal Name
Journal Of Information And Communication Convergence Engineering
Survey on Physical Layer Security in Downlink Networks
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In this paper, we discuss physical layer security techniques in downlink networks, including eavesdroppers. The main objective of using physical layer security is delivering a perfectly secure message from a transmitter to an intended receiver in the presence of passive or active eavesdroppers who are trying to wiretap the information or disturb the network stability. In downlink networks, based on the random feature of channels to terminals, opportunistic user scheduling can be exploited as an additional tool for enhancing physical layer security. We introduce user scheduling strategies and discuss the corresponding performances according to different levels of channel state information (CSI) at the base station (BS). We show that the avai

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Publication Date
Thu Mar 02 2023
Journal Name
8th Engineering And 2nd International Conference For College Of Engineering – University Of Baghdad: Coec8-2021 Proceedings
Using WO3/AlPO4 as a solid catalyst for the transesterification of waste edible oils
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AlPO4 catalysts supported with WO3 were prepared by impregnating the catalysts with ammonium metatungstate. The catalysts were checked by X-ray Diffraction (XRD), AFM, and SEM; also, the catalysts analysis was done by X-Ray (EDX). Finally, the N2 adsorption-desorption was used to measure the pore volume and surface area of the catalyst. The prepared catalyst has a surface area of 185.83 m2/g, pore volume of 0.645 cm3/g at a calcination temperature of 500°C for 3 hrs, and particle size of AlPO4 with an average of 35.36 nm. Transesterification of edible oil using WO3/AlPO4 was performed, it was observed that WO3/AlPO4 catalysts give high conversion of edible oil, and this is attributed to the high surface area, smaller particle size, and the

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Publication Date
Mon Dec 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Biodiesel production from used vegetable oil (sunflower cooking oil) using eggshell as bio catalyst
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Bio-diesel is an attractive fuel fordiesel engines. The feedstock for bio-diesel production is usually vegetable oil, waste cooking oil, or animal fats. This work provides an overview concerning bio-diesel production. Also, this work focuses on the commercial production of biodiesel. The objective is to study the influence of these parameters on the yield of produced. The biodiesel production affecting by many parameters such s alcohol ratio (5%, 10%,15 %, 20%,25%,30%35% vol.), catalyst loading (5,10,15,20,25) g,temperature (45,50,55,60,65,70,75)°C,reaction time (0-6) h, mixing rate (400-1000) rpm. the maximum bio-diesel production yield (95%) was obtained using 20% methanol ratio and 15g biocatalyst at 60°C.

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Publication Date
Wed Jun 01 2022
Journal Name
Canadian Journal Of Chemistry
Hydrogenation of pyridine and hydrogenolysis of piperidine over $γ$-Mo2N catalyst: a DFT study
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Increasing demands on producing environmentally friendly products are becoming a driving force for designing highly active catalysts. Thus, surfaces that efficiently catalyse the nitrogen reduction reactions are greatly sought in moderating air-pollutant emissions. This contribution aims to computationally investigate the hydrodenitrogenation (HDN) networks of pyridine over the γ-Mo2N(111) surface using a density functional theory (DFT) approach. Various adsorption configurations have been considered for the molecularly adsorbed pyridine. Findings indicate that pyridine can be adsorbed via side-on and end-on modes in six geometries in which one adsorption site is revealed to have the lowest adsorption energy (–45.3 kcal/mol). Over a nitr

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