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Effective working parameters of laser micro-/nano-machining
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Modern emerged technologies impose development and fabrication of miniatur-ized parts and devices in the micro- and nano-scale. Producing micro- and nano-featured structures requires nonconventional machining processes where con-ventional machining processes such as grinding, milling and eroding have failed. New emerging processes, such laser machining processes, are still fraught with almost invincible processes. Micro-/nano-machining are the pro-cesses of producing parts, microsystems or features at a scale of a few microm-eters and less than one hundred nanometers, respectively. Precise cutting and clean material removal accompanied with a negligible heat affected zone (HAZ), which are usually the characteristics of laser ablation, have opened a wide door for the evolution of remarkable technologies. This has been demonstrated by applications in different fields such as medicine, biotechnology, materials pro-cessing, microelectromechanical systems, electronics and communications. The continuous development in laser technology in terms of ultra-short pulse width, short wavelength and optics technologies has reduced the drawbacks of diffrac-tion-limited processing accuracies. Laser micro-/nano-machining requires the attainment of high fluence and short interaction time to achieve ablation pro-cesses in nanofabrication and structuring of different materials. To conduct the optimum desired machining process, it is important to integrally consider a number of laser beam and working parameters. Laser wavelength, beam mode, minimum attainable spot size, peak power, pulse duration, pulse repetition rate and scanning speed are some of the important considerations. Manipulating those parameters is crucial for ideal laser ablation represented by yielding the highest resolution of machining with the least lateral dimensions, acceptable depth and minimal or no melt at the edges. The assembly of laser beam delivery and focusing system with an automation system are the essential factors for workpiece positioning and obtaining the desired dimensions. The objective of this chapter is to review the effective parameters associated with laser machin-ing processes that affect the dimensions and quality of laser machining at the micro-/nano-scales in a simple presentation. The review is supported by demonstrating laser processing techniques applied in the field of micro-/nano-machining such as mask, interferometric and scribing techniques.

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Publication Date
Mon Oct 22 2018
Journal Name
Journal Of Economics And Administrative Sciences
The role of organizational learning ability to improve the performance of hospital organizations under the accumulation of intellectual capital Study hospital enterprise sector in Algeria
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        This study aims to identify the amount of the effect of the ability to learn the individuals within the organization on the accumulation of intellectual capital and the role it plays in improving the performance of the organization, and to achieve that, the researcher designed a questionnaire to collect data and information from the surveyed respondents and analyzed using SPSS software, the study concluded after testing hypotheses to have a direct impact between the capacity for organizational learning and the accumulation of intellectual capital, which in turn affects the accumulation of intellectual capital as a positive and direct impact on the performance of the organization, al

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Business incubators the entrance of organizations to shift towards pioneering performance a study by a number of employees of the technical education organizations in mosul
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     The importance of this research is due to its importance goals, Which are about the attempt of researchers to investigate the probability of depending on businesses, environments to transform organizations, performance in away that enhance the leading  role of organizations  in their environments , and through views of a number of the staff working in the foundation of technical institutes in Mosul.  .

     After deciding the methodology of the study that ,in one hand ,performs the goals of the study , and achieving a suitable theoretical framework to present the concepts of businesses, environments and the leadin

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Publication Date
Sun Jan 01 2023
Journal Name
Dental Hypotheses
Assessment of the Impact of Adhesive and Wires Types on the Tensile Bond Strength of Fixed Lingual Retainers Used in Orthodontics: An In Vitro Study
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Introduction: We aimed to assess the impact of adhesive and wires types on the tensile bond strength of fixed lingual retainers. Methods: A total of 160 intact bovine teeth were collected, cleaned, stored in 25% sodium hypochlorite, and randomly assigned to two groups based on the adhesive type: a two-step adhesive and a one-step adhesive. Each group was further divided into four subgroups based on the type of lingual retainer wire, which included (A) 8-strand braided stainless steel wire, (B) three-strand titanium retainer wire, (C) stainless steel chain, and (D) fiber-reinforced retainer. A tensile bond strength test was conducted using a universal testing machine at a controlled speed of 10 mm/min. Result: The 8-strand braided stainles

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Determination of Radionuclides and Heavy Elements in the Rising Dust in the Small Side of Diwaniyah City due to the Movement of Wheels and Cars
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Abstract<p>This research aims to determine the concentration of radionuclides in dust samples on the public streets of the small side of Diwaniyah city in Iraq as a result of movements of wheels and cars using the gamma spectra and high purity germanium detector (HPGe) with resolution of (2.3 keV) for energy (1.332 MeV) of cobalt <sup>60</sup>Co. Dust samples were collected from the streets Diwaniyah city with (26) samples prepared for measurement. The results of the specific activity concentration of Uranium-238, Thorium-232, Potassium-40 and Cesium-137 were (14.66 ± 0.950, 26.29 ± 2.431, 219.04 ± 15.150 and 11.49 ± 0.876) Bq/kg respectively. The radiation parameters Ra<sub>e</sub></p> ... Show More
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Publication Date
Tue Apr 01 2014
Journal Name
Structural Science, Crystal Engineering And Materials
Comparison of the structural motifs and packing arrangements of six novel derivatives and one polymorph of 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine
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The crystal structures of a new polymorph and seven new derivatives of 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine have been characterized and examined along with three structures from the literature to identify trends in their intermolecular contact patterns and packing arrangements in order to develop an insight into the crystallization behaviour of this class of compound. Seven unique C-H...X contacts were identified in the structures and three of these are present in four or more structures, indicating that these are reliable supramolecular synthons. Analysis of the packing arrangements of the molecules using XPac identified two closely related supramolecular constructs that are present in eight of the 11 structures; in all cases, the st

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Publication Date
Mon Jan 01 2024
Journal Name
Journal Of Stomatology
The effect of Winter’s red line, angle of impaction, and radio-morphometric indices on surgical difficulty of impacted mandibular third molar: a prospective observational study
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Publication Date
Sun Sep 26 2021
Journal Name
Modern Sport
The effect of physical exertion exercises using electrical muscle stimulation on the development of some physical and functional characteristics of women aged (40-45) years
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The researchers have recently noticed the interest in the problem of overweight and how to find solutions to it until it is now at the forefront in terms of innovating various and different methods and treatment methods, and the interest in developing health fitness is one of the most important requirements of physical activity for the trainees, which led to the multiplicity of sports activities that promote the health aspect For the individual, in addition to the aesthetic aspect, the problem lies in not adopting training programs according to codified scientific foundations aiming, in addition to reducing weight, to raise the general health level of the trainee participating in fitness institutes, as the trainers do not follow the

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Publication Date
Thu Jun 29 2017
Journal Name
College Of Islamic Sciences
Opinions of Abu Bakr Muhammad bin Al-Fadl Al-Bukhari Al-Hanafi (d. 381 AH): In acts of worship: the books of fasting and Hajj
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In The Name of Allah Most Gracious Most Merciful

Scholars, past and present, have paid attention to the books of Fasting and Hajj, and they have compiled literature on that, and they have written treatises and researches. The best days, and as for the pilgrimage, it is one of the great pillars of Islam, which God Almighty has distinguished by making its rituals in the best of places, which is the Sacred House of God.

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Publication Date
Thu Mar 31 2022
Journal Name
Journal Of The College Of Education For Women
Evaluating Teacher Preparation Programs in Scientific Disciplines at the Faculty of Education in Al-Aqsa University in Light of the Requirements of the Labor Market
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The current study seeks to evaluate teacher preparation programs in the scientific disciplines at the College of Education in Al-Aqsa University in the light of the requirements of the labor market. It further aims to reveal the significance of the differences in the sample members’ response averages of to the availability of labor market requirements in the program that prepares the teacher of scientific disciplines at the Faculty of Education in Al-Aqsa University taking into account the (gender, program) variables. The study followed the descriptive analytical approach, and so a questionnaire was distributed to a sample of scientific discipline students in the teacher preparation program adopted in Al-Aqsa University, (200) male and

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Organizational Red Tapes and their Reflections on Entrepreneurial Orientation: an Exploratory Study of a Sample of Employees in Some Organizations in the Province of Ninewah
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Organizations adopt a number of procedures and instructions in their field of activities in order to aid their resources development   and energies to serve their entrepreneurial orientations. This calls for preparing a range of mechanisms to mitigate the strictness and complexity of procedures. The ambiguity and severe  complexity  of procedures means acknowledging the loss in energy and this in turn  impedes the hopes while in the same time weakens the  enthusiasm in these organizations and an impedes the possibility to achieve continues innovation, thereby losing opportunities to the level of surrender to the risks and  assuming them to be unconquered obstacles.

There

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