حسابات حمل التبريد، العوامل المؤثرة على اكتساب الحرارة، الحرارة المكتسبة, الحرارة المنتقلة خلال المبنى, الحرارة المكتسبة من الشمس, حرارة الإضاءة, حرارة المعدات والموتورات، الحرارة المكتسبة من الأشخاص, حرارة التهوية, الحرارة المكتسبة خلال المسالك الهوائية والمزيد.
In this paper, we studied the static and dynamic behavior of the
silicon carbide Schottky diodes and junction barrier Schottky diodes. The
objective of this study is to understand the performance and
characteristics of these devices in multiple working situations and in high
temperature conditions, as well as to clarify the distinction between these
two types of diodes.
This paper presents a study to reduction of heavy crude oil viscosity by
heating, where we select the best of temperature for all types instead of
constant temperature, whatever composition and viscosity of crude oil.
This work presents the details of the construction of the temperature
control system in the center. We used the Atmega8 microcontroller
which has high performance speed and suitable memory.
This study investigated the effect of adding different
percentages of sand to several types of clay soils, Which used as
liners at solid waste landfill sites in order to find the best mixing
ratio (sand - clay).
The importance of diagram system MnO2─NaVO3 is in obtaining a crystal phase
(chemical compounds or solid solutions). Acknowledging the fact that these compounds
have grade properties in the field of technology, it was important to study the possibi
lity of
obtaining new phases with different mole ratios, and to draw phase diagram for it,
especially the used compounds in this study have different crystal structures.
The samples were made beginning from powders of reagent grade MnO2 and NaVO3 of
5gr for each of them at following percentage mole ratios of MnO2: (10, 20, 25, 30, 33.33,
50, 66.66, 70, 71, 75, 80, 90). The mixing and grinding process was made for these
samples. Then, it made pills ellipsoidal using manually hydraulic press, and it burned into
oven at different degrees. The study was made using powder X─Rays diffraction PXRD
and different thermal analysis TG─ DTA. The results are compared with X─rays
spectrums of grade compounds and parameters of it. Then, the formation phase changes
degrees were determined. New compound was formed at ratio (MnO2)10(NaVO3)90
mole%, and crystal solid solution was formed to ratio (MnO2)25(NaVO3)75 mole%. As well
solid solution (amorphous+ new compound) was formed until mole ratio
(MnO2)75(NaVO3)25 mole%, and amorphous solid solution was formed beginning mole
ratio (MnO2)80(NaVO3)20 mole%, then the phase diagram for the studied system was
drawing.
In this study, the effect of temperature on volume strains in three
types of local clay soils was studied after adding different percentages of
sand for each soil (10%-20%-30%40%-50%) when temperatures change
from (20-60)° C to be used as liners i
n solid waste landfill sites . The
results of the study showed that the mixing of sand with the clay played a
key role in reducing the magnitude of volume strains between (24-27%)
of the value of strains.
تعد الإطارات المستعملة واحدة من أخطر النفايات الصلبة الموجودة في البيئة المحيطة و لاسيما
أنها في ازدياد دائم بسبب ازدياد النشاط البشري في مجال النقل.
و نتيجة التدهور البيئي الناتج عن تراكم هذه النفايات بسبب آثارها البيئية الكبيرة و احتياجها إلى
مس
احة واسعة من مكبات النفايات، إضافة إلى احتمال حدوث حرائق تصعب السيطرة عليها بسبب
قابليتها العالية للاشتعال، كان لابد من إيجاد طريقة للتعامل مع هذه النفايات.
حيث أصبح من الضروري الاستفادة من التقنيات المناسبة لإعادة تدوير هذه النفايات و الاستفادة
منها في الحصول على مصادر أخرى للطاقة.
This research includes the study of energy emulsions used as an alternative fuel
in thermal power stations or in internal combustion engines, and the
mechanism of the formation of emulsions energy, and where the process of
cavitations bubbles form
ed in the fluid as a result of a high-speed spin rotation,
has been studied for the first time in Syria, a detailed study of the terms of the
stability of this type of energy emulsions (Fuel- water).
This article describes physical peculiarities of competitive phase that emerges
when drops of water-fuel emulsion are heated. It is shown that the process of
micro explosion indrops is determined by the amount of water contained in the
fuel and by disparity of emulsion.
In the frame of expanding the concept of optical design to include the designing and manufacturing of opt-mechanical systems, and the effect of static stresses on optical elements due to fastening of metal retainers and the resulting optical performa
nce, a literature review was carried out to show the effect of static stresses on optical elements due to metallic contacts, temperature and adhesives. Numerical method of finite elements to predict the visual performance of optical systems had been performed.
