This research aims to improve the radiation shielding properties of polymer-based materials by mixing PVC with locally available building materials. Specifically, two key parameters of fast neutron attenuation (removal cross-section and half-value layer) were studied for composite materials comprising PVC reinforced with common building materials (cement, sand, gypsum and marble) in different proportions (10%, 30% and 50% by weight). To assess their effectiveness as protection against fast neutrons, the macroscopic neutron cross-section was calculated for each composite. Results show that neutron cross-section values are significantly affected by the reinforcement ratios, and that the composite material PVC + 50% gypsum is an effective shield against fast neutrons.
Objectives: Two derivatives of cephalexin were synthesized by reaction with isatin-glycine Schiff base and bromoisatin-glycine Schiff base separately. Methods: Cephalexin was linked through the amine group to isatin glycine and bromoisatin glycine Schiff bases by amide bond formation. Results: These derivatives were characterized by FT-IR, H-NMR, elemental CHN analysis and then tested for their antimicrobial activity compared to cephalexin against gram-positive, gram-negative bacteria and Candida albicans fungi. Conclusion: The two compounds showed better activity against Staphylococcus aureus, compound 3b is more active against Escherichia coli, and compound 3a is more active against Klebsiella pneumonia.
Two grades of paving asphalt with penetration of 46 and 65 are studied for determining changes in their physical and chemical properties caused by ageing.
The ageing process has been conducted on two petroleum paving asphalt cement using thin film oven test at 150, 163 and 175 C, and ageing time 5, 10,15, 20, 25 and 30 hours. The effect of ageing time and temperature on penetration, kinematic viscosity, softening point, solubility in trichloroethylene, heat loss and changes in chemical composition are investigated. The results of thin film oven test process indicte that the asphaltenes concentration of all aged asphalt increases with increasing ageing time, while the opposite was observed for polar-aromatic and naphthene-aromatic. The
The quality of the financial reports depends on set of accounting standards ,most of wich have been studied for the purpose of ascertaining the relationship between the standard used and the quality of the financial reports that contribute significantly to improving the financial performance of the institution, Research aims to detect the relationship between forensic accounting and the quality of financial reports, The research included a key hypothesis that forensic accountability could be applied to improve the quality of financial reporting, A sample of gentlemen (external auditors, tax assessors, judges, university professors, shareholders) (45
... Show MoreIn this study, thirty-two adult male mice were divided into four groups control and experimental treatment groups received crocin at 4, 20, and 100 mg/kg daily for six weeks. In results, testosterone level was increased significantly from 18.5 ng/dl in the control to 49.3 ng/dl in group received crocin at 20 mg/kg. The regular features of seminiferous tubules with increased Sertoli cells have been observed in the 20mg/kg crocin group. In the group received crocin at 100 mg/kg, many of the seminiferous tubules were atrophic, spermatogenic cells were discontinuous in the same areas while the space among them has been increased, and fewer interstitial tissue between seminiferous tubules were observed. The changes were markedly
... Show MoreSheets of Epoxy (EP) resin with addition of TiO2 of grain size (1.5μm, and 50nm) and weight percentage (1%, 3%, and 5%) were prepared. Discs of 20mm diameter and 3mm thickness were cut for dielectric measurements. Dielectric properties (dielectric constant, dispassion factor and electrical conductivity) over the frequency range 102 -106 Hz were measured.
Comparison was made between the effect of micro and nano particles of TiO2 on the dielectric properties of EP composites with different weight percentage. Epoxy composites with micro sized particles of TiO2 were observed to have the better values of dielectric properties.
This study aims to model the flank wear prediction equation in metal cutting, depending on the workpiece material properties and almost cutting conditions. A new method of energy transferred solution between the cutting tool and workpiece was introduced through the flow stress of chip formation by using the Johnson-Cook model. To investigate this model, an orthogonal cutting test coupled with finite element analysis was carried out to solve this model and finding a wear coefficient of cutting 6061-T6 aluminum and the given carbide tool.
In a world where tourism has become the leading industry on the market, sustainable tourism has found its place and is becoming a major player in the network of traveling Internet users. Hospitality, solidarity and conviviality are essential are giving meaning to sharing. This “extra soul” has the capacity to enrich moments, places, attractions and heritage. Archaeological heritage sites constitute an important factor for the economic and social life of a large number of countries, the development policy came to emphasize the safeguard and the preservation of landscapes and natural or man-made sites, against the attacks which have impoverished the cultural heritage, this heritage
The current research aims to identify the level of digital skills of kindergarten teachers, identify the level of professional competence of kindergarten teachers, as well as to identify the relationship between digital skills and the professional competence of kindergarten teachers. The current research was determined by kindergarten teachers in the second Baghdad / Karkh Education Directorate for the academic year (2021-2022). The research sample consisted of (100) teachers chosen in a simple random way. To achieve the objectives of the research, the researcher developed a digital skills scale of (20) items and a scale of professional competence consisting of (22) items. The results revealed that kindergarten teachers have a high level
... Show More1267 Objectives Aim to evaluate 198Au nanoparticles (AuNP) biodistribution and uptake in a human prostate model for treatment. Many phytochemicals are known to have anti-tumor properties but have short half-lives in vivo. We hypothesized that using these phytochemicals to formulate and coat AuNP would inhibit enzyme cleavage and enhance their anti-tumor properties. Initial evaluations were performed in SCID mice bearing PC3 tumors. Methods : 198AuNP were formulated with the following gum Arabic, epigalocatechin gallate (EGCg) pomegranate extract and mangiferin extract. The resultant nanoparticles were evaluated in normal mice and in human prostate bearing SCID mice. The tumor bearing mice were injected intratumorally with 3-5 uCi of 198A
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