Modification of gas chromatographic technique for the separation and determination of methyl ethoy silane compounds which were synthesized by the addition of absolute ethanol to methyl chlorosilane compounds have been elaborated experimentally. The addition of absolute dry ethanol to methyl chlorosilane compounds in the presence of a dry stream of nitrogen gas led to sweep out the liberated HCl gas. This method was found to be the suitable method for the preparation of methyl ethoxy silane compounds. The optimum parameter selected after careful and precise studies was between 20 – 30 ml \ min to carrieir gas flow rate, while applied temperatures of detector and injection part were 250 °C and 225 °C respectively. The results showed that suitable chromatographic column for the separation of methyl chloro silane compounds is 50% [5% dioctyl phthalate ] + 50% [10% OV- 101 ] .While 10 % OV – 101 column was found to be the best for the separation of methyl ethoxysilane compounds . Accordingly , a linear relationship for the calibration curve between concentration and peak area is achieved for methyl chlorosilane and methyl ethoxysilane . Correlation coefficients here ranged between 1 – 0.9991. The results of percentage RSD alotarned for the methyl chlorosilane and methyl ethoxysilane were 0.512.08 and 0.053-1.37 respectively.
This study offers numerical simulation results using the ABAQUS/CAE version 2019 finite element computer application to examine the performance, and residual strength of eight recycle aggregate RC one-way slabs. Six strengthened by NSM CFRP plates were presented to study the impact of several parameters on their structural behavior. The experimental results of four selected slabs under monotonic load, plus one slab under repeated load, were validated numerically. Then the numerical analysis was extended to different parameters investigation, such as the impact of added CFRP length on ultimate load capacity and load-deflection response and the impact of concrete compressive strength value on the structural performance of
... Show MoreThree hundred and sixty different samples were collected from different sources, including wound, burn, nasal, and oral swabs from several hospitals in Baghdad. A number of 150 (53%) Staphylococcus aureus samples were isolated and identified among a total of 283 samples. Then, the spread of the Toxic Shock Syndrome Toxin-1 gene (tsst-1) was investigated in β-lactamase resistant S. aureus. According to the source of samples, the distribution of S. aureus isolates was found to be significantly higher (p < 0.01) in wound samples as compared to other sources. According to the age, a highly significant distribution (p < 0.01) was recorded in the age group of 15-30 years,
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Background: Osteoporosis is a systemic skeletal disorder that has an impact on general health, dental health and salivary composition. The mineralization of teeth happens simultaneously with that of the skeleton, but if mineral metabolism is disrupted, tooth failures will resemble those that affect bone tissue. Vitamin D plays a key role in bone and tooth mineralization.
Objective: to evaluate the impact of osteoporosis on teeth decay in relation to salivary vitamin D among menopause in Baghdad city.
Subjects and Methods: This study was cross sectional study. The study group consists of
... Show MoreBackground: During pregnancy many physiological, anatomical and biochemical changes take place that affect almost all body systems. In the oral pregnant women have serious changes such as more sever dental caries. This study was conducted to measure dental caries severity and selected salivary variables (salivary flow rate, PH and viscosity)and to find the relation of dental caries with these salivary variables. Subjects, materials and methods: The study group consisted of 60 pregnant women that were divided into three equal groups according to trimester (20 pregnant women in each trimester).They were selected randomly from the Maternal and Child Health Care Centers in Baghdad city, the age range was 20-25 years. In addition to 20 unmarried
... Show MoreThe research aims to measure the relationship and the impact of knowledge management processes to achieve the performance of insurance service, as well as analysis of the reality of the National Insurance Company to identify the level of overall performance, and to achieve this goal, it has been the selection of knowledge management processes according to the survey prepared a supplement to the study (Qubaisi, 2002), and of the four operations (knowledge generation, and storage of knowledge, and the distribution of knowledge, and application of knowledge), which represented the independent variable, and the performance has been the use of quantitative and qualitative measures, (sales growth, customer satisfaction), which represented the
... Show MoreBackground: This in vitro study evaluated the fracture resistance of weakened endodontically treated premolars with class II MOD cavities restored with different composite restorations (Low-shrinkage Filtek P90, nanohybrid Filtek Z250 XT and SDR bulk fill). The type and mode of fracture were also assessed for all the experimental groups. Materials and Method: Fifty human adult maxillary premolar teeth were selected for this study. Standardized extensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved as intact control. The teeth were divided into five groups of ten teeth each (n=10): (Group 1) intact control group, (Group 2) unrestored teeth with endodontic treatment, (Group 3) resto
... Show MoreThe study aims at investigating the effectiveness of the Virtual Library Technology, in developing the achievement of the English Language Skills in the Center of Development and Continuous Education, in comparison with the individual learning via personal computer to investigate the students' attitude towards the use of both approaches. The population of the study includes the participants in the English Language course arranged in the Center. The sample includes 60 students who were randomly chosen from the whole population (participants in English Courses for the year 2009-2010). The sample is randomly chosen and divided into two experimental groups. The first group has learned through classroom technology; while the other group has l
... Show MoreBackground: Neural tube defects (NTDs) are said to be inherited in a multifactorial fashion, i.e. genetic-environmental interaction. Maternal nutritional deficiencies had long been reported to cause NTDs, especially folate deficiency during early pregnancy. More attention had been paid to the exact mechanism by which this deficiency state causes these defects in the developing embryo. The most significant of all researches was that connecting reduced folate and increased homocysteine level in maternal serum on one hand and the risk of developing a NTD baby on the other hand.
Objectives : to determine the significance of homocysteine level in Iraqi mothers who gave birth to babies with NTDs as compare
Renal transplantation is a principal treatment option for end-stage kidney failure. Bone loss and fracture are serious complication of kidney transplantation, associated with morbidity and mortality. The pathogenesis of post transplantation bone loss is multifactorial and complex
Background: Marginal adaptation is critical for long – term success of crown and bridge restoration. Computer aided design / computer aided manufacture (CAD/ CAM) system is gaining more importance in the fabrication of dental restoration. Objective: The aim of this study is to evaluate the effect of crystallization firing on the vertical marginal gap of IPS. emax CAD crowns which fabricated with two different CAD/CAM systems .Materials and Methods: Twenty IPS e.max CAD crowns were fabricated. We had two major groups (A, B) (10 crowns for each group) according to the CAD/CAM system being used: Group A: fabricated with Imes - Icore CAD/CAM system; Group B: fabricated with In Lab Sirona CAD/CAM system. Each group was subdivided into two s
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