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.
This research was designed to study the effect of water and alcoholic crude extracts of Calvatia craniiformis in vitro and in vivo On the other hand this study tested the toxic effect of both extracts in normal laboratory mice. The results showed that water and alcoholic extracts relatively have an acute toxic effect in mice in respect to LD50 (85 mg/kg, and 177mg/kg respectively). However the chronic toxicity of water extract at three different concentration (50, 75, 100 mg/kg) and alcoholic extract at concentrations of (100, 150, 200 mg/kg) was investigated in normal mice by (I.P) administration for 30 days alternatively and one drag in 48 hours . The results indicated significant effect (P ? 0.01) increasing in (MI) and (BI) of bone mar
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Abstract has many advantages as has historically been one of the regions leading cultural centers . for centuries , it has been a center of commertial and financial operations in Iraq. it is also rich in archeological sites and natural resources, but because of its wars and implementation of urban development strategies are effective and sustainable , so contracted the secretariat of Baghdad with the company (khatib and scirntiffic) for the preparation of the comprehensive development plan for the city of Baghdad in 2030 and funded by the world bank and the fact that the plan was approved ( three stages of it ) and only one phase remains the fourth stage, which is under discussion the aim of the
... Show MoreSpiritual is one of modern subjects gained importance of their role in the meaning imparted to work and to promote a sense of belonging to the group and the community, including support personnel positive attitudes towards their work. The research aims to highlight the impact of the relationship between workplace spiritual and variable working attitudes to sample variant of the hospitals, health department BAGHDAD / Rusafa, and in order to achieve this, the researcher is based on the descriptive and analytical approach adopted for the analysis of the questionnaire and to test relations research and its variables. The research community (4) of hospitals in Sadr City, included've targeted 106 doctors and 222 nurses formed a whole (
... Show MoreBackground Many antidiabetic medications with distinct modes of action are available, The sodium glucose cotransporter-2 (SGLT-2) inhibitors are among the most recent oral antihyperglycemic medications. The American Diabetes Association recommends metformin, a biguanide medication, as the first option for oral control of type 2 diabetes because it has demonstrated promise in this regard. Aim of the study To evaluate and compare the effects of metformin and SGLT-2 inhibitors on general urine parameters in T2DM patients from Iraq. Method a prospective cohort study where 101 adult patients of both sexes aged under 70 years and newly diagnosed with T2DM, patients were divided into two groups, Metformin group (n=52), where metformin was p
... Show MoreA reinforced concrete frame is referred as "RIGID FRAMES". However, researches indicate that the Beam-Column joint (BCJ) is definitely not rigid. In addition, extensive research shows that failure may occur at the joint instead of in the beam or the column. Joint failure is known to be a catastrophic type which is difficult to repair.
This study was carried out to investigate the effect of hoops and column axial load on the shear strength of high-strength fiber reinforced Beam-Column Joints by using a numerical model based on finite element method using computer program ANSYS (Version 11.0). The variables are: diameter of hoops and magnitude of column axial load.
The theoretical results obtained from ANSYS program are in a good a
The utilization of recycled brick tile powder as a replacement for conventional filler in the asphalt concrete mix has been studied in this research. This research evaluates the effectiveness of recycled brick tile powder and determines its optimum replacement level. Using recycled brick tile powder is significant from an environmental standpoint as it is a waste product from construction activities. Sixteen asphalt concrete samples were produced, and eight were soaked for a day. Samples contained 5% Bitumen, 2% to 5% brick tile powder, and conventional stone dust filler. The properties of samples were evaluated using the Marshall test. It was observed that the resistance to stiffness and deformation of asphalt concrete
... Show MoreAs a consequence of a terrorist attack, people may experience posttraumatic stress disorder (PTSD) and lack of feeling secure in relationships. This longitudinal study aimed to examine the prevalence of PTSD symptoms over time, the relationship between adult attachment styles and PTSD, as well as their association with degree of exposure, and finally to consider the distribution and the trajectory of attachment styles. The sample consisted of 235 students (M=125, F=110) who were exposed to different levels of trauma intensity in response to a bombing attack. Participants were recruited and assessed approximately 1 month and 5 months after the attack using a battery of questionnaires. Findings revealed, as expected, that 79.5% of the part
... Show MoreA theoretical and protection study was conducted of the corrosion behavior of carbon steel surface with different concentrations of the derivative (Quinolin-2-one), namly (1-Amino-4,7-dimethyl-6-nitro-1H-quinolin-2-one (ADNQ2O)). Theoretically, Density Functional Theory (DFT) of B3LYP/ 6-311++G (2d, 2p) level was used to calculate the optimized geometry, physical properties and chemical inhibition parameters, with the local reactivity to predict both the reactive centers and to locate the possible sites of nucleophilic and electrophilic attacks, in vacuum, and in two solvents (DMSO and H2O), all at the equilibrium geometry. Experimentally, the inhibition efficiencies (%IE) in the saline solution (of 3.5%) NaCl were studied using potentiomet
... Show MoreSurrealism is a twentieth-century literary and artistic movement oriented toward the liberation of the mind. Surrealism is a reaction to the philosophy of rationalism which was believed to be the cause of the disaster of World War I. It emphasizes the expression of the imagination as revealed in dreams and presented without conscious control, the unexpected juxtapositions of objects, the withdrawal of the self, and the exploitation of chance effects.
Surrealism began in Paris in the early 1920s, as Europe emerged from the devastation of World War I. A group of writers, artists, and filmmakers, led by the poet André Breton, adopted the word surréaliste (meaning, roughly, "super-real") as a label for their artistic activities. Influen
The current research aims to identify the " impact of strategic warheads numbered ( NHT) in the collection average second grade students in the article of history). " To achieve this, I assumed the researcher that there is no different between the statistically significant the average score for the collection of experimental group who teaches the Arab Islamic history on and a strategic warheads numbered and the average score for the collection of the control group who were studying the same article according to the classic method ( traditional) . The study sample consisted of 64 students from the second grade average in the secondary warka bin nawfal in the general Directorate for education first karkh in Baghdad for the annual cources 2
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