PVC/Kaolinite composites were prepared by the melt intercalation method. Mechanical properties, thermal properties, flammability and water absorption percentage of prepared samples were tested. Mechanical characteristic such as tensile strength, elongation at break; hardness and impact strength (charpy type) were measured for all samples. It was found that the tensile strength and elongation at break of PVC composites decreased with increasing kaolinite loading. Also, the hardness of the composites increases with increase in filler content .The impact strength of the composites at the beginning increases at lower kaolinite loadings is due to the lack of kaolin adhesion to the matrix. However, at higher kaolin loadings. This severe agglomeration of the filler due to its high surface energy creates many crack-initiation and stress-concentration sites, which are sensitive to impact stresses and cause detrimental effects on the impact properties of the composite. There is a general increase in absorption rate with increase in kaolin content. Thermal properties of PVC /kaolinite composites were characterized using Differential Scanning Calorimetry (DSC) and thermal conductivity analyzer. The results showed Tg shifted toward higher temperature for kaolinite composites compared to neat PVC .Also, thermal conductivity measurement value and effusivity increased with increasing filler loading .Heat capacity decreased with increasing filler content. The higher the filler content the higher burning time, the lower rate of burning and the lower height of the flame which are evident at 12wt. % for kaolinite.
A particulate composite material was prepared by adding the Titanium dioxide (TiO2) with a particle size of (75-150) µm to Epoxy resin at weight percentage of (10%,20%,30%,40%,50%).The following some mechanical properties were studied,fracture toughness, hardness.casting preparation methods were used in this study includes preparing plate of matrix and composites. specimens were prepared according to ASTM for the Mechanical properties tests. After that Another samples were heat treated for three and six hour at 65C?. Fracture toughness (Kic) represent for stress intensity factor results were showed that the curve of three hours aging increases in fracture toughness (Kic) for composites but for six hours aging increases fracture tough
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The experiment was carried out to study the effect of NPK and Inicium using two concentration for each of them 1 and 2 gm/L for NPK and 5 and 10 ml/L for Inicium on some physiological characters of Lycopersicon esculentum and mitotic division index of seedling radical apex. The results showed that all the characters increased plant height, stem diameter, leaves number, length of leaf, lobs number in one leaf, length of root and root diameter. The data showed that the percentage of cell division, mitotic division and Telophase stage increased in seedling radical apex comparison with control plants.
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Polyacrylamide Solutions of different concentrations (0.2, 0.4, 0.6, 0.8, 1.0 %) of Ag nanoparticles and ZnO nanoparticles were prepared, the viscosities and surface tension were measured for all solutions, where measurements indicated an increase in these properties with increased concentration, where the relative viscosity of polyacrylamide/zinc nanoparticles increased from 1.275 to 2.243, and the relative viscosity of polyacrylamide/silver nanoparticles increased from 1.178 to 1.934. Viscosity is significant parameters during electrospinning process. While the surface tension of the polyacrylamide/zinc nanoparticles has changed from 0.0343 Nm-1 to .0.0.0 Nm-1 and changed from .0.000Nm-1 to.0.0.0 Nm-1. Also the constants KH and KK were
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This study is designed to highlight some of the physiological disorders taken place in the renal function, immunological response as well as the ability of the redox system represented by total antioxidant capacity and malondialdehyde levels to combat the toxic exposure of mercuric chloride (HgCl2) with or without collaboration of resveratrol (RES) supplement. Forty-five adult Sprague Dawley, 8-10 weeks old female rats weighing 170-220 g were randomly grouped as following; control group (C) kept without any medication. Dimethyl sulfoxide (DMSO) used as vehicle to prepare RES treatment was given to D-group. RES administered to R-group. Challenge group of rats (HD) was administered HgCl2. The last group of rats (HR) was given HgCl2 with RES i
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ABSTRACT Background: According to Branemark’s protocol, the waiting period between tooth extraction and implant placement is 6–8 months; this is the late placement technique. Achieving and maintaining implant stability are prerequisites for a dental implant to be successful. Resonance Frequency Analysis (RFA) is a noninvasive diagnostic method that measures implant stability. The aim of this study was to investigate the influence of treatment protocol and implant dimensions on primary implant stability utilizing RFA. Materials and methods: This study included 63 Iraqi patients (37 male, 26 female; ranging 22-66 years). According to treatment protocol, the sample was divided into 2 groups; A (delayed) & B (immediate). Dental im
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Methotrexate (MTX) was used for treatment of malignancies and now is widely used in treatment of rheumatoid arthritis. In this research the evaluation of the effects of MTX on some liver enzymes and lipid profile was studied. Twenty four adult female mice divided into three groups (8 mice each). The first two groups were treated with MTX while the third group was used as a control. MTX was intraperitoneally given at 50 µg/ml and 75 µg/ml to the first and second groups respectively for 35 days ,whereas the control group was intraperitoneally injected with normal saline. The results showed a significant (p<0.05) increase in serum levels of glutamic oxaloacetate transaminase (GOT) , glutamic pyruric transaminase (GPT), Alkaline pho
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Background: Obesity increases the host’s susceptibility by modulating the immune and inflammatory systems in a manner that predisposes to inflammatory tissue destruction and leaves an individual at greater risk of periodontitis. Melatonin is a pineal secretory product involved in numerous actions, such as regulation of internal biological clocks and energy metabolism, and it functions as an antioxidant and anti-inflammatory agent. There exists a substantial amount of evidence supporting the beneficial effect of melatonin supplementation on obesity and its complications. Aim of the study: To investigate the effects of systemic melatonin intake on periodontal health status and lipid profiles in obese periodontitis patients. Subjects and met
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