In this study, plain concrete simply supported beams subjected to two points loading were analyzed for the flexure. The numerical model of the beam was constructed in the meso-scale representation of concrete as a two phasic material (aggregate, and mortar). The fracture process of the concrete beams under loading was investigated in the laboratory as well as by the numerical models. The Extended Finite Element Method (XFEM) was employed for the treatment of the discontinuities that appeared during the fracture process in concrete. Finite element method with the feature standard/explicitlywas utilized for the numerical analysis. Aggregate particles were assumedof elliptic shape. Other properties such as grading and sizes of the aggregate particles were taken from standard laboratory tests that conducted on aggregate samples.Two different concrete beamswere experimentally and numerically investigated. The difference between beams was concentrated in the maximum size of aggregate particles. The comparison between experimental and numerical results showed that themeso-scale model gives a good interface for the representing the concrete models in numerical approach. It was concluded that the XFEM is a powerful technique to use for the analysis of the fracture process and crack propagation in concrete.
Rapid, reproducible and accurate method has been developed for the assay for of mebendazol (MBZ) residual assay. The method is based on alkaline hydrolysis of MBZ with sodium hydroxide then oxidation with N-bromosuccinimide (NBS) followed by coupling with 4-Bromoaniline (4-BA) to yield a highly colored product absorbed at maximum 434 nm. Regression analysis of linearity range was found (0.6-2.8) µg.ml-1. The optimum conditions that affect the oxidation were studied. The developed method was found to be precise with mean value of relative standard deviation (1.153- 1.303) and accurate with relative error (-0.5940-1.7821) .The calculated molar absorptivity and sandal sensitivity values of (29825 L.mol-1.cm-1), 0.0099 µg.cm-2 respe
... Show MoreSo far synthesis of Gonadotropin Releasing Hormone (GnRH) analogues reported in the literature has clarified some aspects of structural activity of the naturally released GnRH. As a part of continuing efforts for further understanding of this relationship, the present investigation was undertaken which involved synthesis and biological evaluation of two GnRH analogues, firstly, by replacement of the amino acid L-Argenine in the 8th position at the backbone structure of the natural hormone by the amino acid D-Alanine; and secondly, by replacement of the amino acid L-Glycine in the 10th position by D-Alanine also at the backbone structure of the nature hormone, to obtain the following analogues respectively:
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... Show MoreThin films of ZnSe arc deposited on glass substrates by thermal evaporation in vacuum with different thickness (1000, 2700, 4000) A° temperature (293-373) °K are studies the electrical properties before and after annealing. The result show decrease D.0 conductivity and increasing the activation energy Eat.
In this study, a proposed process for the utilization of hydrogen sulphide separated with other gases from omani natural gas for the production of sulphuric acid by wet sulphuric acid process (WSA) was studied. The processwas simulated at an acid gas feed flow of 5000 m3/hr using Aspen ONE- V7.1-HYSYS software. A sensitivity analysis was conducted to determine the optimum conditions for the operation of plant. This included primarily the threepacked bed reactors connected in series for the production of sulphur trioxidewhich represented the bottleneck of the process. The optimum feed temperature and catalyst bed volume for each reactor were estimated and then used in the simulation of the whole process for tw
... Show MoreRepresent the current study and tagged (the credibility of digital image and its reflection on the process of cognitive picture releases) scientific effort is designed to detect realizing press releases and the extent affected the credibility of the digital image by selecting the relationship between digital photo and the extent of their credibility on the one hand and between the process of cognition and Press Photo of the hand Other than the consequent establishment researcher collects materials to serve the scientific research topic in three chaptersCombine the first one methodological framework for the search of the research problem and its significance and the desired objective be achieved together with the definition of the most im
... Show MoreThe objective of this article is to study the impact of environmental pollution on air, water, and soil quality with a focus on the role of environmental bacteria in bioremediation of pollutants. The research also addresses the ability of some strains of bacteria to remove heavy metals and petroleum hydrocarbons and degrade toxic substances, resulting in improved environmental quality. Outcomes: Empirical studies reveal that environmental pollution leads to significant health and environmental problems, such as a rise in respiratory disease as a result of air pollution, water pollution that affects aquatic life, and soil pollution that decreases crop output. Other bacterial strains such as Pseudomonas, Bacillus, and Streptomyces have also b
... Show MoreThis work deals with the production of light fuel cuts of (gasoline, kerosene and gas oil) by catalytic cracking treatment of secondary product mater (heavy vacuum gas oil) which was produced from the vacuum distillation unit in any petroleum refinery. The objective of this research was to study the effect of the catalyst -to- oil ratio parameter on catalytic cracking process of heavy vacuum gas oil feed at constant temperature (450 °C). The first step of this treatment was, catalytic cracking of this material by constructed batch reactor occupied with auxiliary control devices, at selective range of the catalyst –to- oil ratio parameter ( 2, 2.5, 3 and 3.5) respectively. The conversion of heavy vacuum gas
... Show MoreThe research aimed to explore the recall habits and developing the right recall habits at middle school students. A sample of (40) students were chosen intentionally from middle school students in two schools (almntzr- zany aleabdyn) with an average of (20) students from each school. They were evenly distributed in two experimental and control groups. To achieve the aims of the research, a scale was designed to measure the recall habits, and a preparation of an educational program to develop recall habits.
To process data statistically, the researcher used several statistical methods such as Pearson correlation coefficient, chi-square, T-test for one sample, T-test for two independent samples, Wilcoxon test, Mann-Whitney test, ET
... Show MoreThe present work involves studying the effect of electrolyte composition [@1= 0.5 wt.% NH4F / 5% H2O / 5% Glycerol (GLY)/ 90% Ethylene Glycol (EG)] and [ @2= 0.5 wt. % NH4F / 5% H2O / 95% Ethylene Glycol (EG)] on the structural and photoelectrochemical properties of titania nanotubes arrays (TNTAs). TNTAs substrates were successfully carried out via anodization technique and were carried out in 40 V for one hour in different electrolytes (@1, and @2). The properties of physicochemical of TNTAs were distinguished via an X-ray Diffractometer (XRD), Field Emission Scanning Electron Microscope (FESEM), an Energy Dispersive X-ray (EDX), and UV–visible diffuse reflectance. The photoelectrochemical response of TNTAs was evaluated
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