The purpose of this research is to develop and use two generalized Rational Models (GRM I,
GRM II), each of which is a realizable mathematical model, not available with other models, and
we will demonstrate its utility and applicability on a large
scale, compared to other ( -shaped)
models, and converging well.
In this study, we have investigated the water absorption behavior of unsaturated
polyester /wood flour wastes composites materials. To achieve that, specimens were
prepared by using compressing method with different ratio of polymer matrix with org
anic
wastes produced from carpentry workshop (wood flour).Density of produced panels has
been measured and the obtained results showed that there is an ability to produce
hardindustrial wood panels. Practical experiments had been achieved to determine the
percentages of water absorption. Absorption test was achieved on the cut specimens by
immersing them in natural water (un-distilled) and measuring the gained weight of
specimens and the resulted swelling to determine the final changes in the product. Through
this study, we find that the absorbability has increased with the increment of organic filler
ratio and the practices sizes increment. In addition, we also find that the absorption
behavior follow Fickian law of diffusion in most specimens. We calculated the diffusion
coefficient D and other parameters of diffusion process and we also plotted the associated
plotsof the absorbability results. The obtained results showed that there is an ability to
produce planes of industrial wood without any pretreatment of wood flour.
In this article, we propose a powerful method called
homotopy perturbation method (HPM) for obtaining the
analytical solutions for an non-linear system of partial
differential equations. We begin this article by apply HPM
method for an important models of linear and non-linear
partial differential equations.
This study was conducted on domestic pigeons populations in
the provinces of Hama, Idlib and Latakia using several
conventional diagnostic techniques , including pathological
examination tests and agar gel immune diffusion test and isolation
on c
hicken embryo. The number of suspected birds to be
infected by pigeon pox through clinical symptoms and macroscopic
lesions were about 37 birds. we noticed the presence of lesions
in warts and scars on the nonfeather parts of the face and on the
corner of the mouth and eyelids and other areas of the body. the
most of these accompanied by the presence of the of defteric
lesions on the mucous membrane of the oral cavity.
The results showed that all birds suffered from the presence of
infection fowlpox through histological examination of skin and
difteric lesions. the results has been confirmation by agar gel
immune diffusion test. And we successfully isolated the virus that
caused the disease by injection on the Chorioallantoic membrane
of a chicken's egg fertilized SAN.
In this article, powerful approximate analytical
methods, called Adomian decomposition method and
variational iteration method are introduced and applied to
obtaining the approximate analytical solutions for an
important models of linear and non-
linear partial differential
equations such as ( nonlinear Klein Gordon equation -
nonlinear wave equation - linear telegraph equation -
nonlinear diffusion convection equation ) .
The studied examples are used to reveal that those methods are
very effective and convenient for solving linear and nonlinear
partial differential equations .
Numerical results and comparisons with the exact solution are
included to show validity, ability, accuracy, strength and
effectiveness of those techniques.
معادلة الموجة
wave equation
طريقة تفريق أدوميان
طريقة التكرار التغايري
حدودية أدوميان
معادلة كلاين غوردن
معادلة التلغراف
معادلة الانتشار الحراري
Adomian Decomposition Method
Variational Iteration Method
Adomian Polynomial
Klien Gordon equation
Telegraph equation
Diffusion Convection equation
المزيد..
The free iodine (I2) in povidone-iodine (PVP-I) solutions is responsible for its
bactericidal activity, the bactericidal effect is steadily increased with the free iodine
concentration. This study aims to compare some of povidone-iodine solutions c
ommon at
the local market with one solution produced by Mundipharma company (Betadine®) which
used as a reference. Commercial samples (PVP-I 10%) were obtained from three local
companies (A, B, C), with one batch from each company. The research included
controlling free iodine concentration, pH and evaluation of bactericidal activity by using
disc diffusion method and rapidity of the bactericidal activity on both Staphylococcus
aureus and Escherichia coli. The local samples solutions showed low pH values compared
with Betadine®, furthermore, all the solutions extracted by heptane showed high levels of
free iodine with a preference for one local company. The high level of free iodine was
accompanied with an increase of inhibition diameter and rapidity of bactericidal effect.
In This research a surface hardening process by Ni coating and
subsequent diffusion heat treatments was studied at Al7075 alloy.
Nickel coatings with different thickness were obtained.
In this work, the processing of aluminum alloys - copper, which
added amounts of copper to aluminum in different parentages (2.5-
4-4.5%) so as not to exceed the limit of saturation Aluminum 6 %(
copper).
This paper aims to study the distribution of free nitrogen atoms through surface of α – Fe sample using the numerical solution for linear differential equation by means of Crank – Nicolson method at a temperature range ( 550 to 950 0C) and time inter
val (0 – 8)h where the nitrogen diffusion constant is at 850 0C and 8h.
Under the supposed condition this study has illustrated that the diffusion depth of nitrogen atoms from surface towards inners reaches to ̴ 1.2mm, i.e., determining the layer thickness of the formed nitride compounds which gives the surface layer of α – Fe high resistance against corrosion processes resulting from surrounded environment.
In this research, has been studied the spread of chromium atoms mechanism, and mechanical and chemical and properties of the diffusion chrome coating layer in low carbon steel, which is considered one of the surface treatment techniques. Where many p
ractical experiences were carried out in the powdery saturation milieu to form a diffusion coating layer containing atomic chromium who will spread inside the painted
surface, and has studied some mechanical and chemical properties after doing diffusion chrome coating.
The tests results showed that the tensile strength and micro hardness and chemical corrosion resistance improved after the diffusion chrome coating, also increased the depth of coating layer By increasing the retention time in the oven and temperature, where this relationship is reflected with curve of the second degree. Conversely ductility decreased.
Search results confirm the possibility of using diffusion chrome coating as a promising treatment in raising the efficiency of machinery elements that prone to oxidation or chemical corrosion in different temperatures.