DBN Rashid, INTERNATIONAL JOURNAL OF DEVELOPMENT IN SOCIAL SCIENCE AND HUMANITIES, 2021
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
... Show MoreThe present work aimed to study the efficiency of thermal osmosis process for recovery of water from organic wastewater solution and study the factors affecting the performance of the osmosis cell. The driving force in the thermo osmosis cell is provided by a difference in temperature across the membrane sides between the draw and feed solution. In this research used a cellulose triacetate (CTA), as flat sheet membranes for treatment of organic wastewater under orientation membrane of active layer facing feed solution (FS) and draw solution (DS) is placed against the support layer. The organic materials were phenol, toluene, xylene and BTX (benzene, toluene, and xylene) used as feed solution. The osmotic agent in draw solution was
... Show MoreBackground: In the Thermafil as a root canal obturation, system little is known about the effect that varying rates of insertion have on the adaptability of thermoplasticized GP and the amount of apical extrusion. Materials and methods: thirty simulated root canals were obturated with thermafil obturators and Apexit Plus sealer at three different insertion rates. The obturated canals were sectioned at three different levels, the sealer average film thickness for each section was calculated and the amount of apical extrusion for each canal was conducted. Results: the higher adaptability was seen with the faster insertion rate while the slower insertion rate showed fewer tendencies to cause apical extrusion. Conclusions: the intermediate i
... Show MoreSome geological phenomena as landslides and the mobilization of the accumulated rocks or soil are discussed in this research by using projectiles that cause mobility and falling of these land masses which are present at the top of mountains and edges of roads and streets to avoid accidents and human disasters which will occur if they are left falling by effect of climate or vibrating factors that are produced by performing dams, bridges and reservoirs. According to the different divisions of land masses groups, primary and secondary, which depend on type of movement and material arrangement that form the mobile masses, this research had shown the effect of projectiles for every type of cannons on the mobility of every groups of these rocks
... Show MoreAbstract:
Witness the current business environment changes rapidly reflected on the performance of the facility wishing to stay , which is no longer style reaction enough to handle installations with their environment , and quickly began to lose its luster with the emergence of a message and the vision of contemporary business environment from a set of parts interacting with each other and the concept of behavioral includes all dimensions of performance, it is imperative to adopt a system installations influence variables and positive interaction through the development of strategic plans and the use of implementation and follow-up strategies to ensure the effectiveness of the method for meas
... Show MoreAbstract Background: The emptied sheep’s ovarian follicles recently used as a container for spermatozoa during cryopreservation, it was found a proper carrier to cryopreserving spermatozoa in vapor-dependent cryopreservation. The aim of this study was to evaluate the effect of two periods of exposure to liquid nitrogen (LN2)vapor on the parameter of spermatozoa during cryopreservation in this technique. Method: The study was conducted on 30 semen samples from patients with oligozoospermia diagnosed by semen analysis according to the standard criteria of World Health Orgnization (WHO) 2010. Sheep’s ovarian follicles obtained from local slaughterhouse and prepared by slicing the ovaries and evacuating the follicular fluid and oocyt
... Show MoreCriticism is inherently impolite and a face-threatening act generally leading to conflicts among interlocutors. It is equally challenging for both native and non-native speakers, and needs pre-planning before performing it. The current research examines the production of non-institutional criticism by Iraqi EFL university learners and American native speakers. More specifically, it explores to what extent Iraqi EFL learners and American native speakers vary in (i) performing criticism, (ii) mitigating criticism, and (iii) their pragmatic choices according to the contextual variables of power and distance. To collect data, a discourse-completion task was used to elicit written data from 20 Iraqi EFL learners and 20 American native speaker
... Show MoreIn this research, the possibility of using waste wooden materials (reed and sawdust) was studied to produce sustainable and thermal insulation lightweight building units , which has economic and environmental advantages. This study is intended to produce light weight building units with low thermal conductivity, so it can be used as partitions to improve the thermal insulation in buildings. Waste wooden materials were used as a partial replacement of natural sand, in different percentages (10, 20, 30, and 40) % . The mix proportions were (1:2.5) (cement: fine aggregate) with w/c of 0.4. The values of 28 days oven dry density ranged between (2060-1693) kg/m3.The thermal conductivity decreased from (0.745 to 0.2
... Show More