The free electron laser is considered one of these important and advanced inventions because it provides a laser beam within various wavelengths of the electromagnetic spectrum. In any laser system device, several parameters must be available on which the efficiency and performance of the laser system are dependent. The Pierce parameter is one of the important parameters in measuring the performance quality of the free electron laser. In this paper, the simulation results were obtained using the MATLAB program to show the important effect of the Pierce parameter on the performance of the free electron laser system. The simulation results showed that the values of the Pierce parameter ranged between (0.01 - 0.03) for the laser beam with long wavelengths, while it ranged between (0.001-0.0001) for the short wavelengths. The results showed an increase in the efficiency values of the free electron laser system with increasing the values of the Pierce parameter, which represents the ratio between the saturation power and the power of the electron; therefore, it can be used as a specific threshold to measure the efficiency of the laser system. Additionally, the simulation of the Pierce parameter has a direct relation to the small signal gain per unit length.
The durability of asphalt concrete is highly dependent on the geometry and mineralogy of coarse aggregates, yet their combined influence on mechanical and moisture resistance properties is still not fully understood. This study evaluates the effects of coarse aggregate geometry, specifically flat and elongated particle ratios and angularity, as well as mineral composition (quartz versus calcite), on asphalt mixture durability. The durability of mixtures was evaluated through Marshall properties as well as moisture susceptibility indicators, including the tensile strength ratio (TSR) and index of retained strength (IRS). Statistical analyses (ANOVA and t-tests) were also conducted to confirm the significance of the observed effects.
... Show MoreABSTRACT: BACKGROUND: Coriandrum Sativum is a native of Mediterranean region and is grown in North Africa, central Europe, and Asia as culinary herb and medicament. In addition to the other health-supporting reputation, coriander has hypoglycemic, hypolipidemic, and aphrodisiac effects. OBJECTIVE: To study the effect of Coriandrum Sativum on process of spermatogenesis. MATERIALS AND METHODS: Coriandrum sativum was given daily to mature male rats in a dose of 50mg/ 100g body weight for 14 days. 10% formalin fixed paraffin-embedded tissue sections were performed for histological and morphometrical studies. RESULTS: Histological study showed wider seminiferous tubules & increased spermatocytes population with an increased sperm density
... Show MoreAfter the twenty – first century become necessary for us motorcade era in educational a chevements by searching for the best strategies and teaching methods and techniques artotalbagesh resorting to the strategy
Did not use in use in the teaching of the foreseeable material general by voice and teaching perspective for the student of the class fourth science
In particular ,so the researcher asking the question follows:
Can the peer education strategy to have an impact in perspective drawing skill development ?
From here it demonstrated the importance of current research know the impact of p
... Show MoreInfluence of metal nanoparticles synthesized by microorganisms upon soil-borne microscopic fungus Aspergillus terreus K-8 was studied. It was established that the metal nanoparticles synthesized by microorganisms affect the enzymatic activity of the studied culture. Silver nanoparticles lead to a decrease in cellulase activity and completely suppress the amylase activity of the fungus, while copper nanoparticles completely inhibit the activity of both the cellulase complex and amylase. The obtained results imply that the large-scale use of silver and copper nanoparticles may disrupt biological processes in the soil and cause change in the physiological and biochemical state of soil-borne microorganisms as well.
A novel encapsulated deep eutectic solvent (DES) was introduced for biodiesel production via a two-step process. The DES was encapsulated in medical capsules and were used to reduce the free fatty acid (FFA) content of acidic crude palm oil (ACPO) to the minimum acceptable level (< 1%). The DES was synthesized from methyltriphenylphosphonium bromide (MTPB) and p-toluenesulfonic acid (PTSA). The effects pertaining to different operating conditions such as capsule dosage, reaction time, molar ratio, and reaction temperature were optimized. The FFA content of ACPO was reduced from existing 9.61% to less than 1% under optimum operating conditions. This indicated that encapsulated MTPB-DES performed high catalytic activity in FFA esterificatio
... Show MoreThe aim of this investigation is to study and analysis the role of governance in the evaluation of the and social performance of the economic units to be addressed through the concept of corporate governance and then to the social performance and its relationship to corporate governance.
The most important obtained results from this research is that the corporate governance of extreme importance, and derive their importance from being an essential tool to contribute to the transparency and fair disclosure of the financial results of economic units in the fight against financial and administrative corruption in economic units, thus providing protection and confidence of all parties, and the evaluating soci
... Show MoreFirst: People’s need for advocacy:
Calling for a legal necessity for all people, regardless of their races, colours, tongues, and culture, to explain the truth, spread fear, bring benefits, ward off evil, regulate a person’s relationship with his Lord, and his relationship with creatures, so that he knows his money and what he owes.
All of creation is in dire need of the call to God’s religion with insight due to their inability to reach out to goodness, righteousness, guidance, and success on their own. Man is limited in thinking in this universe, limited in his resolve, unable to know what will improve his affairs in the two worlds. His need for religion is one of the necessities of his life, and one of the comple
... Show MoreSummary of the research : Our research tagged (Arabic language in the media between warning and development) attempts to follow the most prominent phenomena that accompanied the evolution of the use of Arabic language in the media with the development of these means and spread technically globally, and how divided researchers and linguists and intellectuals Arabs into two teams, each demanding what contradicts the other, in the matter The use of the Arabic language in the media, and the arguments of each team in the need to deal with the media as one of the pillars of the nation culturally, historically and civilized, in order to enhance its position and maintain unity, continued the research highlighted the positions of hard-lin
... Show Morethe appearance and increasing of the young immigration within 2015, the researcher intuition as a mother and part of the society, and the role of the psychological attitude in enabling the individual to make decision, in the light of all the above come up the need for studying this problem.
The study aims at finding out:
1. The mental strain of the study sample.
2. The differences in mental strain of the study sample according to the gender, specification, the university, the study (private, not private), and if they have immigrated friends or relatives out of the Iraq.
3. The study sample attitudes towards immigration.
4. The study sample levels of attitudes towards immigration.
5. The differences in the sample attitud