In this work, the finite element analysis of moving coordinates has been used to study the thermal behavior of the tissue subjected to both continuous wave and pulsed CO2 laser. The results are compared with previously published data, and a good agreement has been found, which verifies the implemented theory. Some conclusions are obtained; As pulse width decreases, or repetition rate increases, or fluence increases then the char depth is decreased which can be explained by an increase in induced energy or its rate, which increases the ablation rate, leading to a decrease in char depth. Thus: An increase in the fluence or decreasing pulse width or increasing repetition rate will increase ablation rate, which will increase the depth of cutting. The selection of a proper laser parameters may be helpful for doctors in obtaining optimum advantages in such treatment.
Cutting forces are important factors for determining machine serviceability and product quality. Factors such as speed feed, depth of cut and tool noise radius affect on surface roughness and cutting forces in turning operation. The artificial neural network model was used to predict cutting forces with related to inputs including cutting speed (m/min), feed rate (mm/rev), depth of cut (mm) and work piece hardness (Map). The outputs of the ANN model are the machined cutting force parameters, the neural network showed that all (outputs) of all components of the processing force cutting force FT (N), feed force FA (N) and radial force FR (N) perfect accordance with the experimental data. Twenty-five samp
... Show MoreAbstract: Background: Optical biosensors offer excellent properties and methods for detecting bacteria when compared to traditional analytical techniques. It allows direct detection of many biological and chemical materials. Bacteria are found in the human body naturally non-pathogenic and pathologically, as they are found in other living organisms. One of these bacteria is Escherichia coli (E. coli) which are found in the human body in its natural and pathogenic form. E.coli bacteria cause many diseases, including Stomach, intestines, urinary system infections, and others. The aim of this study: is sensing and differentiation between normal flora and pathogenic E.coli. Material and method:
... Show Morethe study aimed to identify the impact of the types of cooking utensils in transition metal elements to food and the effect of acid and storage in the concentration of these elements. used five types of cooking utensils including aluminum. tefal, astainls steel, glass. (pyrex), and ceramic prepared in it the food meal. the same meals were repeated add to them acid. the estimate of mineral elements in the meal prepared before storage and after storage in refrigerator temperature degree. the result shows the increase of aluminum concentration in the meals that prepared in aluminum pot reaching 2.913 pmm while reached less concentration in the meal prepared in astainls pot reaching 0.325 pmm. the highest concentration of iron reached 25.2 p
... Show MoreFar infrared photoconductive detectors based on multi-wall carbon nanotubes (MWCNTs) were fabricated and their characteristics were tested. MWCNTs films deposited on porous silicon (PSi) nanosurface by dip and drop coating techniques. Two types of deposited methods were used; dip coating sand drop –by-drop methods. As well as two types of detector were fabricated one with aluminum mask and the other without, and their figures of merits were studied. The detectors were illuminated by 2.2 and 2.5 Watt from CO2 of 10.6 m and tested. The surface morphology for the films is studied using AFM and SEM micrographs. The films show homogeneous distributed for CNTs on the PSi layer. The root mean square (r.m.s.) of the films surface roughness in
... Show MoreThe symbolic image refers to the thing which symbolizes it and embodies
the meaning in the recipient's conscience taking into consideration the
general context. The thesis of Al-Nibahi is based on a simple tale stating that
the palm, which had a venerable status among the Arabs because of its good
origin, ingrained springing and its delicious fruit, lost its status; however, it
continued standing in veneration and silence near the wall of Alhambra. This
palm has complained from harm and negligence, as it has warned of the
waste, and awakened the people to present the defect of its harm. This
research finds through these ideas that the palm was a symbol of the remains of the Arabic sovereignty which restricted
The objective of this study is to determine the efficacy of class V Er:YAG laser (2940 nm) cavity preparation and conventional bur cavity preparation regarding Intrapulpal temperature rise during cavity preparation in extracted human premolar teeth. Twenty non carious premolar teeth extracted for orthodontic purposes were used and class V cavity preparation was applied both buccal and lingual sides for each tooth .Samples were equally grouped into two major groups according to cavity depth (1mm and 2mm). Each major group was further subdivided into two subgroupsof ten teeth for each (twenty cavities for each subgroup). TwinlightEr:YAG laser (2940 nm) with 500mJ pulse energy, P.R.R of 10 Hz and 63.69 J/cm2 energy density was used. The ana
... Show MoreAbstract
The population is sets of vocabulary common in character or characters and it’s study subject or research . statistically , this sets is called study population (or abridgement population ) such as set of person or trees of special kind of fruits or animals or product any country for any commodity through infinite temporal period term ... etc.
The population maybe finite if we can enclose the number of its members such as the students of finite school grade . and maybe infinite if we can not enclose the number of it is members such as stars or aquatic creatures in the sea . when we study any character for population the statistical data is concentrate by two metho
... Show MoreThe current research aims to provide a philosophical and knowledge framework to explain the issue of organizations dealing with Paradox phenomena by focusing on five main aspects. The first deals with the concept of paradox, and the second aspect deals with the types of forces paradox. While the third aspect regards subject of the philosophy of paradox in organization theory and the fourth side deals with methods of solving the paradox. Finally, the last side is exposed to the subject of the paradoxes of the three provided by the study (L
... Show MoreThis work describes an experimental setup to evaluate the photodynamictoxicity of 650 nm diode laser and 532 nm Frequency-doubled Q-Switched Nd:YAG laser on the growth of Candida albicans as well as the potential fungicidal effect when combining the laser irradiation with specific photosensitizers namely methylene blue, toluidine blue, acridine orange and safranin O. In this study the findings showed that the number of colony-forming units per millilitre (CFU/ml) of C. albicans decreased with increasing exposure time. In particular in the case of the frequency doubled Nd:YAG laser combined with safranin O, the best lethal effect occurred at 11 minutes exposure time with 2.26 J/cm² energy density (89.18% reduction) in comparison with the
... Show More