Al-Nahrain Journal for Engineering Sciences

The critical heat flux (CHF) in forced
convective up flow has been investigated in a
uniformly heated vertical steel tube of 18 mm
internal diameter and 3.66 m length, with water as
the working fluid. The CHF was determined by the
sudden rise in the wall temperature of the
electrically heated tube. Experiments were
performed at nominal pressure 50 bar over three
mass flux values 0.11kg/s, 0.055kg/s and 0.027
kg/s, and heat flux with up to 400 kW maximum
power. The CHF results in the present experimental
ranges rise linearly as the mass flux increases.
Finally, a comparison of the experimental data with
available fluid correlations has been performed. The
present results of CHF are found to be an acceptable
agreement with those predicted by using (Bowring
Correlation) and are slightly higher when compared
with those predicted by Katto and Ohne Correlation

The study in present paper deals with find the
analytical and experimental for optimum of thick
composite plate made of nylon weave woven
fabrics with polyester (ply angle and stacking
sequences) with two optimization strategy (linear
programming LP and genetic algorithm GA) for
simply supported thick plate with central point
load condition tacking in consideration the price
and weight of materials in used. A simulation
program build with MATLAB to find out the
optimum design and finally compare the results
using ANSYS then for check the manufacturing
quality of plates, the first natural frequencies of
prepared plates and ANSYS model is compared.
From this paper results, the maximum difference
between the LP and GA optimization with
displacement ANSYS results are 5% and 7%
respectively, and the maximum difference between
the experimental and ANSYS of the first natural
frequency results are 18% and 19% LP and GA
results respectively.

The effect of welding parameters on mechanical
properties of aluminum alloy 3003 H14 Friction
stir-welded (FSW) joints were investigated in the
present study. Different welded specimens were
produced by employing variable rotating speeds
(1000, 1250, 1500, 2000 r.p.m.), and welding
speeds (20, 40, 60, 80 mm/min). Microhardness
measurements and tensile strength of the
produced joints were tested. The experimental
results indicated that the process parameters have
a significant effect on mechanical properties of
joints. The optimum results of the weld gained at
the parameter 80mm/min weld speed and 1500
rpm rotation speed where the efficiency reaches
to 89% of the ultimate tensile strength of the
parent metal

:
The goal of the present research was to
study the effect of curing time on the mechanical
properties of particular composite. Of critical
importance was the capability to predict resin flow
and compaction during cure. Such a model could be
used to determine optimum cure cycles without a
need for experimental trial and error.
The experimental work includes steps .The
first step is mixing the polyester with the Alumina
powder with particular size ranged from 25 to 36
m with different weight ratios (0, 10, 20, and
30%) and the second steps is putting it in the heater
furnace at 70oC at different curing time (1, 2 and 3
hours) to known the properties acquired and the
third step is tested in the tensile test for all
specimens. The conclusion of this test is
summarized that the curing time of the presented
composite is about 2 hour with 70oC.

Isothermal vapor-liquid equilibrium
data of five groups, which are polar-polar at
low and high pressure, polar-non polar at low
and high pressure, and non polar-non polar at
high pressure were investigated. Each group of
these contains four binary mixtures with 334
overall data points. By using PRSV-EOS with
WS and HVOS mixing rules at infinite
pressure where
GE

obtained by adopting
UNIQUAC and Wilson models. These mixing
rules have many advantages and can handle all the
systems with good accuracy. Noting that WS mixing
rules have one adjustable parameter and HVOS
mixing rules without adjustable parameter. Many
efforts to modify the results were made. The best
modification which gives the more accurate results
for all groups is the introduction of a new constant
value „C‟ which is specified for each system in
HVOS mixing rules with quadratic mixing rules
with one adjustable parameter hij.

for the determination of tetracycline (TC),
and tetracycline’s derivatives; doxycycline
(doxysam), chlortetracycline (chlor-TC), and
oxytetracycline (oxy-TC), in Nineveh Drug
Factory (NDF) antibiotic industrial water course
effluent, using solid-phase extraction followed by
liquid chromatography separation. The
identification of the target antibiotics in
environmental samples was based on comparison
of their HPLC peaks with those of the
corresponding reference standard solutions. It
was found that compromisingly satisfactory
separation of the investigated antibiotics and
stable base line could be achieved by using
acetonitrile–formic acid solution as a binary
mobile phase system. Still the compounds were
separated on a Sep-Pak C18 cartridge with a
resolve CN guard column using gradient elution
and UV wavelength of 280 nm. The reported data
indicated that tetracycline is the most frequently
detected antibiotic in the samples. It was detected
in five out of eight effluent water samples, with
the maximum concentration of 0.412 µg/l.
Doxycycline were detected in four with a
maximum of 0.349 µg/l, chlortetracycline was
found in only one sample (0.358 µg/l), while
oxytetracycline was not detected.

The use of fingerprint in biometric identification
has been the most widely used authentication
system. The uniqueness of the fingerprint for every
human provides us with all we need for faultless
identification. However, during the fingerprint
scanning process, the image generated by the
scanner may be slightly different during each scan.
This paper puts the implementation of Artificial
Neural Networks to provide an efficient matching
algorithm for fingerprint authentication. Using the
Back-Propagation technique, the algorithm works
to match twelve fingerprint parameters and relate
them to a unique number provided for each
authorized user. Upon matching, the algorithm
returns the best match for the given fingerprint
parameters.

The sunlight is suggested to be used in solar
surgery as an alternative to the laser surgery. The
rays of powerful sunlight are collected,
concentrated and transported to the operating
theatre from outside through a system of optical
fibers in order to use this solar energy in tumor
and cancer cell evaporation instead of lasers. The
idea of solar surgery is still new and need more
practical and design enhancements. This study is
a step on this way. A Schmidt Cassegrainien
arrangement is suggested for this optical solar
system design calculations. It consists of a
parabolic dish to concentrate the solar radiation
on a secondary flat mirror which directs the light
into a fused silica optical fiber cable used to carry
the concentrated solar beam from the
concentrating system to the operation room.The
parabolic reflector dish rim half angle was chosen
to be 45o
to realize high flux and high efficiency.
MATLAB program (version 7.00) has been used
to calculate the diameter of the primary parabolic
dish, the diameter of the secondary flat mirror and
its recession from the fiber tips by two design
procedures. The first procedure of these
calculations is based on starting with the choice of
the optical fiber diameter, while the second design
procedure is based on the choosing first the distal
end diameter of the optical fiber.The calculations
of the second procedure showed more practical
results. As the most often used fiber distal
diameter in surgery is 0.6mm, then according to
calculations the diameter of the primary parabolic
dish reflector will be 180mm with a focal length
of 108.64mm. The small secondary mirror is
perfectly flat of 10.5mm in diameter and its
recession from the fiber tip is 5.27mm.
Another MATLAB program has been written to
find the suitable numerical aperture for the optical
fiber of the concentrator system to reach
maximum efficiency of the system. It was found
to be 0.7 theoretically. The nearest available value
of NA for fused silica fiber was 0.66. Fused silica
optical fiber of 1mm for core diameter was
chosen because of its ability to withstand the high
degree of temperature. It is found that this optical
system could deliver a flux density as high as
73Wmm-2
for contact surgery and 32Wmm-2
for
noncontact surgery.