When employing shorter (sub picosecond) laser pulses, in ablation kinetics the features appear which can no longer be described in the context of the conventional thermal model. Meanwhile, the ablation of materials with the aid of ultra-short (sub picosecond) laser pulses is applied for micromechanical processing. Physical mechanisms and theoretical models of laser ablation are discussed. Typical associated phenomena are qualitatively regarded and methods for studying them quantitatively are considered. Calculated results relevant to ablation kinetics for a number of substances are presented and compared with experimental data. Ultra-short laser ablation with two-temperature model was quantitatively investigated. A two-temperature model for the description of transition phenomena in a non-equilibrium electron gas and a lattice under picosecond laser irradiation is proposed. Some characteristics are hard to measure directly at all. That is why the analysis of physical mechanisms involved in the ablation process by ultra-short laser pulses has to be performed on the basis of a theoretical consideration of `indirect' experimental data. For Copper and Nickel metal targets, the two-temperature model calculations explain that the temperature of the electron subsystem increased suddenly and approached a peak value at the end of laser pulse. In addition, the temperature profile of lattice temperature subsystem evolution slowly, and still increasing after the end of laser pulse. A good agreement prevails when a comparison between the present results and published results.
It is necessary to use the means of recovery and other means that help to get rid of the effects of fatigue, as the game of badminton and the effectiveness of running 800 meters fall within the mixed system with the superiority of the anaerobic system by more than the air system, so requires the development of energy systems In proportion to the time of the match for badminton players and their travels and high performance and ability to tolerate the high level of lactic acid in the muscles and blood and increase the pain associated with the fatigue that occurs during the performance. In light of the physical and physiological processes of these actions N it should seek through training programs to develop your endurance and wind energy sys
... Show MoreIn this paper we study the selection of cognitive elements and criteria of the inflectional structure of the Russian and Arabic languages in the process of speech communication. Phonetic-physiological principle is the main parameter by which the elements and criteria of cognitive activity in the presented study are distinguished. On the basis of the above mentioned parameter, we select the investigated criteria and elements. The first criterion is semantic, reflects the accordance of the elements of thinking to sound combinations in the studied languages, and allows us to distinguish the second criterion – morphonological. The second criterion depends on the phonetic changes of these combinations occurring in the process of speech activit
... Show MoreA simulation study is used to examine the robustness of some estimators on a multiple linear regression model with problems of multicollinearity and non-normal errors, the Ordinary least Squares (LS) ,Ridge Regression, Ridge Least Absolute Value (RLAV), Weighted Ridge (WRID), MM and a robust ridge regression estimator MM estimator, which denoted as RMM this is the modification of the Ridge regression by incorporating robust MM estimator . finialy, we show that RMM is the best among the other estimators
The purpose of this paper is to identifying the level of skill self-esteem of the young tennis players in the Governorate of Baghdad, identifying some aspects of attention (acuteness, concentration, and diversion of attention) among the young tennis players of the Baghdad governorate, and identify the skills of serve and serve spiking in tennis by young tennis players in Baghdad governorate. The researchers used the descriptive approach in the correlative relations style for its suitability and the research problem. the research sample was chosen in a deliberate way from the youth team players in tennis for the Governorate of Baghdad and the participants in the 2021-2022 sports season, whose number is (20) male players and (4) young playe
... Show MoreIn this paper, an experimental analysis of conventional air-cooled and microchannel condensers in automotive vapor compression refrigeration cycle concerning heat transfer coefficient and energy using R134a as a refrigerant was presented. The performance of two condensers and cycles tested regarding ambient temperature which it was varied from 40oC to 65oC, while the indoor temperature and load have been set to be 23oC and 2200 W respectively. Results showed that the microchannel condenser has 224 % and 77 % higher refrigerant side and air side heat transfer coefficient respectively than the coefficients of the conventional condenser. Thus, the COP, in case of using the microchannel
... Show MoreBackground: Soft Laser has been advantageous in medical applications and is widely used in clinical practice. It is applied because it doesn’t cause the significant thermal effects or tissue hurt when irradiated. The blood response to low power laser radiation provides information about processes of laser radiation interaction with live creatures. Objective: The aim of the current work was to evaluate the laser-induced changes of in vitro erythrocyte sedimentation rate (ESR), mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentration (MCHC) in patients with breast cancer by irradiating a human blood sample using a green laser and comparing its effects before and after irradiation with the same power density (100mW/c
... Show MoreProvisions and controls on the disposal of public funds between Sharia and law
Research Summary
That money is the foundation of life and one of the most important reasons for the reconstruction of the land, and God is the owner
The real value of this money, God has borrowed some individuals on public money, and people
They are charged with preserving it, since it is beneficial to them all, without anyone taking it
To himself, and the guardian is charged by God to protect this money and aggression
Because of its power, authority, various organs and public servants of the province
Upon him; Because the assault on public money by employees and others in the organs of the state
And exploitation of their jobs and this
Background : The dermatophytesare taxonomically related fungi causing different skin infections referred to as tineas in man or ringworm in man and animals . Objective:This study was established to investigate theof effect of yellow sap and gel of Aloe vera on skin of the rabbits which infected with T.verrucosum. Methods : Twelveskin biopsy were taken from rabbits for histopathological study to know the the effects of the T.verrucosumand treated with yellow sap and gel. Results : the results of histopathological study of effect of yellow sap and gel of Aloe vera on skin of the rabbits which infected with T.verrucosum showed the concentration of the gel of aloe vera at 75% was more effected to treat the infective area of skin with T.verrucos
... Show MoreThe research aims to understand the psychological status of and the feeling of loneliness of the trainees (recently released detainees) participating in the training and rehabilitation courses held in the Technical College - Baghdad. The study was conducted on a specimen of (23) trainees. An open questionnaire was adopted which included one question that was ( What was your feeling psychologically and socially before taking part in the training course?) , also the feeling of loneliness Scale , designed by ( Russel,Peplau, Cutrona /University of California Los Angeles ) was implemented after the courses .
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... Show MoreAn advertisement is a human activity as old as human societies. As it was practiced by each society in accordance with the circumstances of the times and the means of communication available. The evolution of advertisement in the modern era reflected many factors to become an essential part of the lives of individuals in the world. Interesting in television advertising has increased in particular because it is the first and most influential mass media in the minds of people.
Advertisements play a big role in our lives as individuals. As advertisements surround us where we have been found; and bring us many benefits; as well as their contribution to accelerate the process of economic development a
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