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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
Sun Mar 01 2015
Journal Name
Baghdad Science Journal
The Effect of Age and Gender on Fetuin-A and Some Biochemical parameters in Blood Sera of Iraqi patients with T2DM: A comparative study
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The serum protein test includes measurement of the level of total protein(albumin, globulin). Fetuin-A is a blood protein made in liver. It can inhibit insulin receptor, enhance insulin sensitivity and make the individuals more likely to develop type 2 diabetes, then disorder in lipid profile (Total cholesterol(TC), low density lipoprotein cholesterol (LDL-c), high density lipoprotein cholesterol (HDL-c), Triglyceride(TG) and very low density lipoprotein cholesterol (VLDL-c) . To evaluate Fetuin-A, total protein, albumin, globulin, HbAlc and lipid profile in 200 adult and elderly Iraqi patients with type 2 Diabetes Mellitus were taken and compare them with 200 subjects as a healthy control. The laboratory analysis(for patients and

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Publication Date
Wed Dec 01 2010
Journal Name
Iraqi Journal Of Physics
Study of electron energy distribution function and transport parameters for CF4 and Ar gases discharge by using the solution of Boltzmann equation-Part I
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The Boltzmann transport equation is solved by using two- terms approximation for pure gases . This method of solution is used to calculate the electron energy distribution function and electric transport parameters were evaluated in the range of E/N varying from . 172152110./510.VcmENVcm
From the results we can conclude that the electron energy distribution function of CF4 gas is nearly Maxwellian at (1,2)Td, and when E/N increase the distribution function is non Maxwellian. Behavior of electrons transport parameters is nearly from the experimental results in references. The drift velocity of electron in carbon tetraflouride is large compared with other gases

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Publication Date
Tue Mar 03 2020
Journal Name
Aip Conference Proceedings
Correlation study of (IL-17, IL-17RA) and some biochemical parameters with patients of Iraq colorectal cancer after and before taking a dose of chemotherapy
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Colorectal cancer CRC is the third most commonly diagnosed cancer in males and the second in female, so it is a common and life-threatening disease serum of 48 males and 40 females suffering from CRC disease as group one (G1) without taking a chemotherapy dose, the same patients group tow (G2) after taking the first chemotherapy dose, while group three (G3) whose patients in (G1) and (G2) after second taking a chemotherapy dose. and group four (G4) consist of (30 males and 30 females) healthy Iraqi control. Results showed a significant increase in IL-17, IL-17RA and CEA in G1, while there was a significant decrease in vitamin D concentration in G1 than other groups, also there was positive (+ ve) significant correlation between IL-17 and CE

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Publication Date
Sun Jan 14 2018
Journal Name
Journal Of Engineering
The effect of Laser Shock Peening on Fatigue Life Using Pure Water and Hydrofluoric Acid As a Confining Layer of Al – Alloy 7075-T6
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Laser shock peening (LSP) is deemed as a deep-rooted technology for stimulating compressive residual stresses below the surface of metallic elements. As a result, fatigue lifespan is improved, and the substance properties become further resistant to wear and corrosion. The LSP provides more unfailing surface treatment and a potential decrease in microstructural damage. Laser shock peening is a well-organized method measured up to the mechanical shoot peening. This kind of surface handling can be fulfilled via an intense laser pulse focused on a substantial surface in extremely shorter intervals. In this work, Hydrofluoric Acid (HF) and pure water as a coating layer were utilized as a new technique to improve the properti

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Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
Effect of Red Laser Irradiation on The Optical Properties of Cobalt oxide (CoO<sub>2</sub>) Thin Films deposited via Semi-Computerized Spraying Technique
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Abstract<p>The existing investigation explains the consequence of irradiation of red laser on the optic properties of (CoO<sub>2</sub>) films. The film was equipped by the utilization of semi-computerized spray pyrolysis technique (SCSPT), it is the first time that this technique is used in the preparation and irradiation using a laser in this technique. From the XRD analysis, the crystalline existence with trigonal crystal system was when the received films were processed by continuous red laser (700 nm) with power (>1000mW)for different laser irradiation time using different number of times a laser scan (0, 6, 9, 12, 15 and 18 times) with total irradiation time(0,30,45,60,75,90 mi</p> ... Show More
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Publication Date
Tue Oct 01 2024
Journal Name
Journal Of Alloys And Compounds
Conversion of preferred crystalline orientation by annealing and its impacts on the structural, electronic, and optical properties of pulsed laser-deposited CdO thin films
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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Between Ordinary Methods (LS,IV) and Robust Methods (2SWLS,LTS,RA) to estimate the Parameters of ARX(1,1,1) Model for Electric Loads
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Abstract:

The models of time series often suffer from the problem of the existence of outliers ​​that accompany the data collection process for many reasons, their existence may have a significant impact on the estimation of the parameters of the studied model. Access to highly efficient estimators  is one of the most important stages of statistical analysis, And it is therefore important to choose the appropriate methods to obtain good  estimators. The aim of this research is to compare the ordinary estimators and the robust estimators of the estimation of the parameters of

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Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Kinetics and Energetic Parameters Study of Phenol Removal from Aqueous Solution by Electro-Fenton Advanced Oxidation Using Modified Electrodes with PbO2 and Graphene
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The Electro-Fenton oxidation process is one of the essential advanced electrochemical oxidation processes used to treat Phenol and its derivatives in wastewater. The Electro-Fenton oxidation process was carried out at an ambient temperature at different current density (2, 4, 6, 8 mA/cm2) for up to 6 h. Sodium Sulfate at a concentration of 0.05M was used as a supporting electrolyte, and 0.4 mM of Ferrous ion concentration (Fe2+) was used as a catalyst. The electrolyte cell consists of graphite modified by an electrodepositing layer of PbO2 on its surface as anode and carbon fiber modified with Graphene as a cathode. The results indicated that Phenol concentration decreases with an increase in current dens

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Publication Date
Thu Apr 01 2021
Journal Name
Biochem. Cell. Arch.
AGE AND GENDER IMPACT ON GLYCAEMIC CONTROL, RENAL FUNCTION AND OXIDATIVE STRESS PARAMETERS IN IRAQI PATIENTS TYPE 2 DIABETES MELLITUS
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Type 2 daibetes mellitus (T2DM) is a global concern boosted by both population growth and ageing, the majority of affected people are aged between (40- 59 year). The objective of this research was to estimate the impact of age and gender on glycaemic control parameters: Fasting blood glucose (FBC), glycated hemoglobin (HbA1C), insulin, insulin resistance (IR) and insulin sensitivity (IS), renal function parameters: urea, creatinine and oxidative stress parameters: total antioxidant capacity (TAC) and reactive oxygen species (ROS). Eighty-one random samples of T2DM patients (35 men and 46 women) were included in this study, their average age was 52.75±9.63 year. Current study found that FBG, HbA1C and IR were highly significant (P<0.01) inc

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Publication Date
Sun Jun 29 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Salivary microRNAs (hsa-miR-200a, hsa-miR-125a and hsa- miR-93) in relation to age, gender and histopathological parameters.
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Background: MicroRNAs (miRNAs) are small noncoding RNAs that post‐transcriptionally regulate gene expression by targeting specific mRNAs. The main objective of this study was measure the level of salivary (hsa-miR-200a, hsa-miR-125a and hsa- miR-93) in both oral squamous cell carcinoma and healthy controls to asses the association of them with age, gender and tumor grade materials and methods The level of three salivary microRNAs namely hsa-miR-200a, hsa-miR-125a and hsa- miR-93 were measured in saliva of patients with oral squamous cell carcinoma and healthy controls by using reveres transcription, preamplification and quantitative PCR also the general information from each patient including the age, sex and tumor grade were record

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