This research introduces a developed analytical method to determine the nominal and maximum tensile stress and investigate the stress concentration factor. The required tooth fillets parametric equations and gears dimensions have been reformulated to take into account the asymmetric fillets radiuses, asymmetric pressure angle, and profile shifting non-standard modifications. An analytical technique has been developed for the determination of tooth weakest section location for standard, asymmetric fillet radiuses, asymmetric pressure angle and profile shifted involute helical and spur gears. Moreover, an analytical equation to evaluate gear tooth-loading angle at any radial distance on the involute profile of spur and helical gears, (taking into account the effect of profile shift factor) has been derived. In addition, numerical solution for the evaluation of the maximum fillet tensile stress and the combined tensile stress concentration factor for the verification of the analytical method using computer-aided engineering software (ANSYS Version 18.1). The analytical and FE result have been compared and found to be very close. The most effective method for reducing the stress concentration factor have been found by applying negative profile shifting on asymmetric tooth with lower unloaded pressure angle and high loaded pressure angle and fillet radius, which can lead to an enhancement percentage of (20%) when using a (35o/20o) asymmetric spur gear of a (24) teeth number with a shift factor of (-0.3mo) compared with standard (20o) one.
In this study the Fourier Transform Infrared Spectrophotometry (FTIR) provides a quick, efficient and relatively inexpensive method for identifying and quantifying gypsum concentrations in the samples taken from different sites from different localities from Alexandria district southwest Baghdad. A comprehensive spectroscopic study of gypsum-calcite system was reported to give good results for the first time by using IR for analytical grades of gypsum (CaSO4.2H2O) and calcite (CaCO3) pure crystals. The spectral results were used to create a calibration curve relates the two minerals concentrations to the intensity (peaks) of FTIR absorbance and applies this calibration to specify gypsum and calcite concentrations in Iraqi gypsife
... Show MoreIn this study the Fourier Transform Infrared Spectrophotometry (FTIR) provides a quick, efficient and relatively inexpensive method for identifying and quantifying gypsum concentrations in the samples taken from different sites from different localities from Alexandria district southwest Baghdad. A comprehensive spectroscopic study of gypsum-calcite system was reported to give good results for the first time by using IR for analytical grades of gypsum (CaSO4.2H2O) and calcite (CaCO3) pure crystals. The spectral results were used to create a calibration curve relates the two minerals concentrations to the intensity (peaks) of FTIR absorbance and applies this calibration to specify gypsum and calcite concentrations in Iraqi gypsiferous soi
... Show MoreThe aim of this paper is to investigate the effects of Nd:YAG laser shock processing (LSP) on micro-hardness and surface roughness of 86400Cu-Zn alloy. X-ray fluorescence technique was used to analyze the chemical composition of this alloy. LSP treatment was performed with a Q-switched Nd: YAG laser with a wavelength of 1064 nm. The results show that laser shock processing can significantly increase. The micro-hardness and surface roughness of the LSP-treated sample. Vickers diamond indenter was used to measure the micro-hardness of all samples with different laser pulse energy and the different number of laser pulses. It is found that the metal hardness can be significantly increased to more than 80% by increasing the laser energy and t
... Show MoreThe aim of current study is estimate the ability of low cost adsorbents, which consist of extracted silica from rice husk ash in treatment of Industrial waste water that contains heavy metals (Cd, Co and Pb) with other pollutants by fixed filters technique with determine the best method for that, and study the effect of a number of variables and parameters. This study involved one waste water samples were collected from. State battery manufacturing company (SBMC) (before treatment unit) at 5th and 22th, of the January 2015. Adsorption tests showed that all tested adsorbent materials had a significant heavy metal removal efficiency. pH values showed a significant impact on adsorption process, but best removal efficiency occurred at pH 4.5
... Show MoreThis research display a selected sample of Regelson's texts, there were interrelations and interactions unfolded so as to show his creativity in the employment of religious texts. In the story "In the Youth of Moses", he inter-texted the episode of the Prophet Moses from the Torah, the Source of legislation, to signify a legislative issue needed by the community. As for the story of "Samson, One of the Falling", he originated the character of The Judge Samson by alluding to the Book of the Judges, which is the Book which reminded of the defeat and slavery of the Palestinians by a Jewish leader, as is related in Jewish religious texts. Further, and the story of "And Haman Said", he chose the story of the Queen Esther from the Book of Esth
... Show MoreThis study examined the effects of a few biochemical variables on obese Iraqi males and females with a 30.5 body mass index (BMI) when they were fed a ketogenic diet. The present study demonstrates how an individual who follows a ketogenic diet has an increase in low-density lipoprotein (LDL-cholesterol). This research's objective was to assess the levels of some biochemical variables in obese people who were eating a ketogenic diet. Following 35 days on a ketogenic diet, the results show a significantly higher P ≤ 0.05 level of low-density lipoprotein (LDL) and total cholesterol (TC). Additionally, insulin, fasting blood sugar (FBS), cortisol, HOMA-IR, urea, BMI, and creatinine all show a considerable reduction, P ≤
... Show MoreAsprosin was a novel adipokine that was released by white adipose tissue. It was activated by fasting and attracted to the liver, which allowed the liver to rapidly release glucose into the bloodstream. White adipose tissue was the source of asprosin. When people go on a fast, their blood sugar levels drop, which causes levels of the hormone asprosin to rise. It does this by binding to a G-protein-coupled receptor in the liver known as OR4M1, which in turn activates a cascade that involves the G -protein-cAMP-PKA pathway. Because of this, the glucose that is stored in the liver is released. We anticipate that by investigating the changes that occur in asprosin levels in hypothyroidism patients, we will be able to make a significant
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This study “discusses the benefit of “addition waste paper as a “new cellulose material “in mortar mixes. A partial addition of waste paper by cement weight was achieved to produce cement composite mortar. Pulp and paper is the third major industrial dumper of air, soil and water. In recent year, paper and paperboard constitute a greater portion of many countries’ urban solid discarded generation. Beside, it increases characteristic “strength due to existence “of hydrogen links “in the microstructure of “paper. Furthermore, it consume “better thermal protection. The addition percentages “of waste paper used “in this work were (5%, 10%, 15% and 20%) by “mass of cement to measure and evaluat
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