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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 02 2023
Journal Name
Journal Of Polymer Research
Morphological study of porous aromatic schiff bases as a highly effective carbon dioxide storages
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Carbon dioxide (CO2) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO2 capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO2 storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO2 sorption properties. We find that Schiff base complexes exhibit high CO2 adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressu

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Publication Date
Mon Dec 20 2021
Journal Name
Baghdad Science Journal
Effective Solution of University Course Timetabling using Particle Swarm Optimizer based Hyper Heuristic approach
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The university course timetable problem (UCTP) is typically a combinatorial optimization problem. Manually achieving a useful timetable requires many days of effort, and the results are still unsatisfactory. unsatisfactory. Various states of art methods (heuristic, meta-heuristic) are used to satisfactorily solve UCTP. However, these approaches typically represent the instance-specific solutions. The hyper-heuristic framework adequately addresses this complex problem. This research proposed Particle Swarm Optimizer-based Hyper Heuristic (HH PSO) to solve UCTP efficiently. PSO is used as a higher-level method that selects low-level heuristics (LLH) sequence which further generates an optimal solution. The proposed a

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Publication Date
Wed Dec 14 2022
Journal Name
Journal Of The College Of Languages (jcl)
Effective Metadiscourse Strategies in Texts of English and Arabic Trade Agreements to attain persuasion
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Persuasion is a process studied by many scholars from the Greek time until the present. One persuasion strategy is metadiscourse, which refers to the writers' awareness of their text, the way they present themselves to the readers. The writers use metadiscourse markers to help the readers understand the real meaning of the text (Hyland 2005).  The paper carries out a qualitative and quantitative analysis of the employment of persuasive metadiscourse markers in two English trade agreements and two Arabic agreements has provided in terms of Hyland's (2005) model of interactive and interactional markers. The aim is to find out whether all types of metadiscourse markers are used or not, and also to see whether English or Arabic employs

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Publication Date
Thu Dec 01 2022
Journal Name
Baghdad Science Journal
The Effective M3Y Residual Interaction In 41Ca As a Nuclear Diffraction Grating of Electrons
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The total and individual multipole moments of  magnetic electron scattering form factors in 41Ca  have been investigated using a widely successful model which is the nuclear shell model configurations keeping in mind of 1f7/2 subshell as an L-S shell and Millinar, Baymann, Zamick as L-S shell (F7MBZ) to give the model space  wave vector. Also, harmonic oscillator wave functions have been used as wave function of a single particle in 1f7/2  shell. Nucleus 40Ca as core closed and Core polarization effects have been used as a corrective with first order correction concept to basic computation of L-S shell and the excitement energy has been implemented with 2ћω. The

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Publication Date
Thu Jun 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
Mechanical evaluation of nano hydroxyapatite, chitosan and collagen composite coating compared with nano hydroxyapatite coating on commercially pure titanium dental implant
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Background: Dental implants act as infrastructure for fixed restoration to look like as a natural tooth. Osseointegration is a biological events and considered as a base for success of dental implant. The aim of this study is to evaluate the bond strength between bone and Ti implant coated with mixture of nano hydroxyapatite-chitosan-collagen compared with Ti implants coated with nano hydroxyapatite implanted in rabbit tibia, after different period of implantation time (two and six weeks) by torque removal test. Material and methods: 36 screws of commercially pure titanium; 8mm in length and 3mm diameter , 18 screws coated with mixture of nano hydroxyapatite-chitosan-collagen and18 screws coated with nano hydroxyapatite by dip coating. St

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Publication Date
Tue Jan 01 2019
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees19gr
The effective of partial replacement of barium by yttrium on HgBa2-xYxCa2Cu3O8+δ superconducting compound
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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Study of some effective factors on the production of garamicidin from locally isolated Bacillus brevis
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The optimum cultural conditions for garamicidin production by local isolate B.brevis were studied.Best result was obtained when the isolate B.brevis was grown on media composed of 1%glucose as carbon source,1% ammonium chloride as a nitrogen source ,0.5% Dipotassium hydrogen orthophosphate as a phosphate source and after 48 hours of incubation at 30C .Garamicidin has been extracted and purified through acid precipition and then extracted by organic solvent (ether& acetone ).Using HPLC the garamicidin antibiotic showed three types A,B and C garamicidin .

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Crisis management effective of business organizations in the era of managerial technique: a philosophical study
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At a time of increasing human potential in the face of crises and risks through the use of technology on a large scale and steadily in various fields of life, and the vulnerability of business organizations as a result of mistakes. The failure of a sudden these errors or omissions or symptoms. Also, some crises occur outside the control of management, others caused by leakage of important information and sometimes secret may be a strategy or a new plan or new project occurs outside the organization to the opposite of what is planned. Therefore, the crisis management are critical to all organizations, because the active management of the crisis helps to ensure the continued prosperity of the organization. Here comes from the resea

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Publication Date
Sun Jun 11 2017
Journal Name
Al-academy
Shape of Round house as an Effective Strategy in the Collection of Art Education Students
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The two researchers selected the problem of research which represented with the following asking: Does the use of the shape of Round house strategy have effectiveness in the collection of students of the Department of Art Education of the subjectof teaching methods?
The research aims to "measure the effectiveness of Strategy shape of Round house in the collection of students of the Department of Art Education for the material teaching methods" and to verify the aim of the research two zeroassumptions was identified to measure the level of achievement in the subject of teaching methods of third stage students in the Department of Art Education –College of Fine Arts.
The research community included the students of Art Education Dep

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Publication Date
Wed Jul 14 2021
Journal Name
The Open Civil Engineering Journal
Producing Sustainable Concrete using Nano Recycled Glass
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Background:

Many tools and techniques have been recently adopted to develop construction materials that are less harmful and friendlier to the environment. New products can be achieved through the recycling of waste material. Thus, this study aims to use recycled glass bottles as sustainable materials.

Objective:

Our challenge is to use nano glass powder by the addition or replacement of the weight of the cement for producing concrete with enhanced strength.

Methods:

A nano recycled glass p

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