In the present work usedNd:YAG laser systems of different output characteristic were employed to study the drilling process of material used in scientific and industrial fields. This material include Manganese hard steel. Our study went into the affecting parameters in drilling of Manganese hard steel by laser. Drilling process is achieved through material absorption of part of the incident laser beam. It is the resultant of interfering both, laser beam and material properties and the focusing conditions of the beam. The results as shown that the increase in the laser pulse energy over the used level has raised the hole diameter, depth and increased the hole taper. In addition to that a hole taper was affected by the laser energy, the focusing position and focal length of the lens used.
This research aims to identify the impact of Daniel's model on the development of critical thinking. In order to achieve this objective, the following hypotheses are formulated: 1. There is no statistically significant difference at the significance level (0.05) between the average differences in the posttest scores of the experimental group taught according to Daniel's model and the control group taught according to the traditional method in the measure of critical thinking. 2. There is no statistically significant difference at the significance level (0.05) between the average differences in the preand post-tests scores of the experimental group taught according to Daniel's model in the measure of critical thinking. The current research i
... Show MoreThis experiment examined the effects of adding sodium alginate and KOJIC acid as substitutes of Conventional antibiotics to soybean lecithin extender on the characteristics of cryopreserved and frozen buffalo bull semen, as well as evaluation of their additions as antibiotics that to help lowering the microbial load. Following the collection and dilution of in the soybean lecithin extender, the experimental treatments were separated into five groups, as follows: T1: (control-) without adding any antibiotics; T2: (control+) adding the conventional antibiotics Gentamicin 0.4 IU and Tylosin 0.08 IU per 100 ml; T3: adding Kojic acid at (0.06 g/L) T4: adding sodium alginate at (0.6 mg/mL)T
This research aims to modify the components of stainless steel alloy by the method of surface engineering through the single diffusion coating technique in order to obtain new alloys with high efficiency in resisting harsh environmental conditions. Steam a mixture of sodium chloride ( ) and sodium sulfate ( ) at a temperature of 900 and then compare it with the base alloy. The results showed that the alloys produced in this way are very efficient. The results showed that the aluminum coating showed high efficiency in resisting oxidation and provided better protection for a longer time compared to the uncoated alloy due to the oxide crust layer formed with high adhesion as well as the aluminum-rich phases, whether the phase
... Show More1-Objective:- Polyphenols are biochemical compounds with antioxidant activity against differences diseases related to Lipid peroxidation such as diabetes mellitus. Polyphenols distributed widely in medical plants, the aim of the study is to extract and analyze some polyphenolic compounds from grape seeds and examine their effects on (STZ) induced diabetic mice. 2-Methods:- In the present study , a group of polyphenols has been extracted from Iraq
... Show MoreThe experiment was conducted in two stages: first stage: determination of the most effective dose of Cyperus rotundus tubers aquatic extract in male rats for 5 days, which was concentrated as (200 mg/kg body weight). The second stage was designed to observe and test the protective effects of C. rotundus tubers aquatic extract in the liver and kidney functions of male rats exposed to cadmium chloride poisoning (5 mg/kg bw) for 30 days. The animals were divided into (4) groups within each group (5) animals weighted (200-220g). The results of oral dose of cadmium chloride showed a significant increase of (P˂0.05) in the activity of both enzymes Alanine aminotransferas
... Show MoreThis study illustrates the impact of non-thermal plasma (Cold Atmospheric Plasma CAP) on the lipids blood, the study in vivo. The lipids are (cholesterol, HDL-Cholesterol, LDL-Cholesterol and triglyceride) are tested. (FE-DBD) scheme of probe diameter 4cm is used for this purpose, and the output voltage ranged from (0-20) kV with variable frequency (0-30) kHz. The effect of non-thermal atmospheric plasma on lipids were studied with different exposure durations (20,30) sec. As a result, the longer plasma exposure duration decreases more lipids in blood.