Issue 11
Aluminum Concentrations in Baghdad Water Supplies During 2004
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1301-1315
Alum represents the most coagulant used for water treatment .It is used due to
its low cost and efficiency. However, there are many disadvantages, mainly some
effects due to aluminum accumulation with time in human mind causing
Alzheimer,s disease.
In this work, Samples of water were collected and tested for residual aluminum
concentration as a fieldwork investigation in the distribution system of Baghdad
City. Samples of raw water were also taken from the intake of water treatment
plants located along Tigris River in Baghdad (Al-Karkh, East Tigris, Al-Karama,
Al-Wathba, Al-Dora, Al-Wahda and Al-Rasheed ), then samples of tap water were
taken from some regions which the project supply and comparing it with the Iraqi
standards. Samples collection were continued for four months (February, April,
May, July) –2004 . The results indicated that aluminum concentrations decreased
with increasing distance from water treatment plants due to the precipitation of
aluminum hydroxides on pipes wall, results had showed that most samples were
within standards except Al-Rasheed water treatment plant which showed that 70%
of samples exceeded the health limit (0.1 mg/L) and 30% of samples exceeded the
aesthetic limits (0.2 mg/L) at the beginning of the water treatment plant .While in
other water treatment plants percents were as follows: 35% of the samples exceeded
health limits and did not exceeded the aesthetic limit in Al-Karkh water treatment
plant ,45% of samples exceeded the health limit and 10% of samples exceeded the
aesthetic limit in East Tigris water treatment plant, 33% of samples exceeded the
health limit and in other points there were no samples exceeded the aesthetic limit
in Al-Karama water treatment plant .Percent of samples which exceeded the health
limit was 35% and there were no samples exceeded aesthetic limit in Al-Wathba
water treatment plant .While that in Al-Dora and Al-Wahda water treatment plants
shows that no samples out of the range for both health and aesthetic limits
Adaptation of BPSK/TH/UWB Parameters Using RAKE Receiver with IPI in WPAN Indoor Multipath Fading Channels
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1316-1325
In this paper, the performance of a PRAKE receiver for a pulse based ultra-wideband
(UWB) communications system is studied in a realistic channel model that is based on an
extensive set of indoor channel measurements. The adaptation of parameters of Binary Phase
shift Keying/Time Hopping/Ultra Wideband (BPSK/TH/UWB) using PRAKE receiver is
shown to contribute to a mitigation of the Inter-pulse interference (IPI). This work is based
on the adaptation of multiple access parameters to mitigate the effect of IPI in a certain level.
This study is done on the Wireless Personal Area Network (WPAN) IEEE802.15.3a, CM3
channel which is used for indoor network applications. Simulated results show the
performance improvement in terms of BER. The results show improvements in the BER due
to the adaptation of the values of number of pulses Ns and the number of chips per frame Nh.
This is done simply by adjusting the bit rate Rb to a certain value and varies the value of Ns
and Nh such that their product has a similar value. In this way the IPI is reduced because it is
hardly depends on Ns and Nh
RECLAMATION OF PCB WASTEWATER
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1326-1340
Wastewater from electronic printed circuit board (PCB) factories was subjected
to lab-scale ion exchangers of two types: strong acid cation followed by weak base
anion exchanger. The experimental investigation was directed to study the ion
exchanger performance in terms of three different parameters namely (TDS, feed
rate and bed depth). Box-Wilson composite rotatable design was adopted in
designing the experiments. Breakthrough times of (PCB) wastewater were studied
through TDS ranged between 317 to 1193 ppm, feed rate ranged between 0.712 to
4.980 l/h, and bed depth of cation exchanger ranged between 9.4 to 60.6 cm and
anion exchanger ranged between 14.3 to 91.0 cm.
Simulation the effect of the studied variables through their pre-designed ranges
in terms of breakthrough time by 2nd order polynomial equation was obtained. In
general, the performance and characteristics of adopting two bed deionizers (cation
and anion beds) was proved efficient for the removal of the ionic contaminants and
not less than 95 % of wastewater is recycled. In addition, the research considers the
treatment of highly metals content regenerant solution out coming from
reclamation system to minimize its metal content. The reclamation of wastewater
was studied in terms of breakthrough time (i.e., the leakage of the cations).
The Determination of Optimum Conditions for Anodizing Aluminum Alloy (6063)
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1341-1354
Aluminum alloy (6063) has been anodized using sulfuric acid as an
electrolyte. To study the characteristic of the anodic film, four variables, were
considered as the most dominant variables. These variables are: current density in the
range of 1- 4 A/dm2, electrolyte concentration in the range of 6 - 20 vol.%, electrolyte
temperature in the range of 10- 30oC and anodizing time between 12- 60 min.
These four variables are manipulated through the experimental work using Box –
Wilson experimental design where second order polynomial model was proposed to
correlate the studied variables with the thickness of anodic film of aluminum alloy
(6063) to estimate the coefficients of the proposed polynomial adopted via statistica
software.
The predicated models are found after statistically analyzing the significance as
follows:
Y= 27.7800 + 8.0737X1 - 0.8037X3 + 8.2078X4 - 0.6994X2
1 - 0.8882X2
2
- 1.5582X2
3 - 1.1231X1X2 + 2.6225X1X4 - 1.7931X2X3 - 1.6956X2X4
- 1.0581X3X4
where Y is the objective function (thickness of anodic film), X1 is the current density;
X2 is the electrolyte concentration; X3 is the temperature of electrolyte and X4 is the
anodizing time.
The study shows that the anodizing time and current density had shown positive
dependence of great significance on the anodic film thickness while the other two
studied variables (i.e. concentration and temperature of electrolyte) had shown small
dependence on the film thickness of aluminum alloy (6063).
Optimum conditions for achieving the maximum film thickness are obtained from
optimizing the above correlation and are found as follow: 4 A /dm2 Current
density, 6 vol. % Acid concentration, 19.5 oC Electrolyte temperature and 60 min.
time of anodizing.
Design Voltage Regulator for Synchronous Generator
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1355-1368
As the loud on an alternator is varied, its terminal voltage is also found to
vary. This variation terminal voltage is due to voltage drop in armature
(resistance, leakage reactance) and armature reaction, therefore this
research aim to design voltage regulator to maintain the terminal voltage of
alternator at constant value at load condition. By making the compensation
time of voltage drop approach to zero at load condition.
Oxidation and Corrosion Mechanism of Steel Alloys and Inconel 600 Alloy in Liquid–Lead-Bismuth Eutectic
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1369-1383
The alloys used in this study were two types pf stainless steels (304SS and
316 SS) , low alloy steel (Type T22-ASTM) and Inconel 600 alloy `(nickelbase
superalloy). The oxidation mechanism were studied for three steel
alloys and for inconel 600 in liquid Pb-Bi eutectic (LBE) in the temperature
range 450- 550 oC using stagnant test . A model based on the experiments
of Cr oxidation at high temperature with scale vaporization was applied to
the present oxidation process by replacing the vaporization rate with the
mass-transfer-corrosion rate. The results indicate that all steel alloys
showed an oxidation/corrosion behavior. The oxidation kinetics is parabolic
and the corrosion kinetics is linear. The parabolic oxidation rate constant
are of the following order (Kp) 304SS (Kp) 316SS > (Kp) low alloy steel .
The scale-removal-rate constants Kr by mass transfer corrosion are of the
following order (Kr) inconel > (Kr) 316SS > (Kr) 304SS . The weight loss
increases with increasing Ni content in the steel alloys.
3D Surface Generation Algorithm Using Lagrange Basis Functions in CAD/CAM Application
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1384-1395
The objective of this paper is to create an efficient and accurate 3D surface
interior data depending on primary initial data based on Lagrangian interpolation
concept. The presented algorithm of 3D surface generation is an extended of the
conventional Lagrangian interpolation (1D). The interior data of the designed
surface have been transformed automatically to a vertical CNC milling machine
(Bridge-port) through the serial port (RS232) to machine the designed 3D surfaces,
where the toolpath have been generated based on linear interpolation techniques.
The result of the proposed algorithm have been compared with the well know
"Hermit, Bezier and B-Spline" 3D surface generation methods.
Removal Of Chromium From Electroplating Wastewater By Simple Chemical Treatment And Ion Exchange
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1396-1404
Wastewater from metal plating works was treated with lime - water
suspensions at relatively small concentrations with continuous stirring.
Experiments were designed to allow a direct contact of lime suspension
with the wastewater constituents for a period of time followed by settling
and filtration through a sand filter. The heavy metal content could be
precipitated efficiently from the mother liquor by two mechanisms: reaction
with calcium ions to yield calcium chromate and the precipitation of the
chromium hydroxides in the alkaline medium. Various parameters were
studied to reach the optimum conditions for the removal of chromium from
the wastewater. It appeared that reasonable removal of chromium (80 –
85%) could be achieved with lime: wastewater ratio of 40 mg/ L and 50 min
contact time. After the removal of most of the chromium from wastewater,
the level of the pollutant needed to be reduced to the acceptable limit by
passing water through ion exchange column. This final treatment gave
treated water samples with chromium levels as low as 0.6 - 1.3 mg/L.
The Determination Of Desertification Phenomena Using Remote Sensing Techniques
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1405-1410
In this present work, the digital image analysis is used as a
developed remote sensing technique to study the effects of desertification
phenomena in Karbala South west of Iraq. Two satellite images used in this
study with coverage area of 80 km2. The first was SPOT panchromatic
image, 10 m resolution taken in 1999. The second was Landsat (TM) visible
image, 30m resolution taken in 1987.
An area of 1 km2 was selected from each image to be the site of the
field experiment. The experiment period was six months from. Nine points
were selected within the selected area to be the measuring points. The
measurements were done every two months for both the vertical and
horizontal accumulated sand in the nine points. These field measurements
led to an average of 1.5 cm/day of sand creeping within the measuring
period.
Prediction of Cutting Forces by using Machine Parameters in end Milling Process
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1423-1428
Cutting forces produce deformations along cutting tool which is one of
the mechanical machining errors, so that cutting force during a milling
operation can be simulated in tool geometry during cutting condition
and workpiece, then studying this forces to estimate by using a values
which is produce from longitudinal component of the cutting force, then
the results accuracy between experiment and predict cutting force is
92%.
Role of Conjugative Plasmids in Antibiotic Resistance between Two Strains of E. coli
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 1429-1437
Two isolated bacterial strains (E. coli 64, E. coli MM294), were purified,
they are: gram-negative bacteria, circular, regular edged, thick somewhat
glitter, viscous, and lactose fermenter. They belong to the family of
Enterobacteriaceae E. coli 64 showed the resistant to all used antibiotics
except Rifampicin (RA), Cephotaxime (CTX), Nitrofurantion (FT),
Tabramycin (TM), and Cephalexin (RX) (Sensitive to). While E. coli
MM294 showed the sensitivity to all used antibiotics except: Rifampicin
(RA), Lincomycin (L), Clindamycin (CM), and Erythromycin (E),
(resistantt to) Conjugative experiments showed that E. coli strain 64
harbored a self transmissible plasmid carrying resistant genes for:
Tetracycline (TE), Amoxicillin (AMX), Neomycin (N), Chloramphenicol
(C), Ampicillin (AM), and Trimethoprime + Sulfamethorazole (SXT) It
seems that all these resistant genes may be carried on one self transmissible
plasmid, or they may be carried on one self transmissible plasmid (except
Neomycin, resistant gene may carry on other self transmissible plasmid)..
A Study Into Some Thermal Properties of Novolak and its Composites
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 438-449
The research involves using phenol-formaldehyde (novolak) resin as a
matrix for making composite material, while glass fiber type (E) and asbestos fiber
type chrysolite were used as reinforcing materials. The specimens of composite
materials were prepared from each type of all the fibers mentioned above with
weight fraction of (60%) of their weight. After that the hybrid composite material
was made by the addition of different types of these fibers in the same weight
fraction, these specimens were made in different ratios of hexamethylenetetramine
content including (10%) and (14%). Then the study on some thermal properties
was carried out on all composites which were prepared and the results were
compared with those of novolak resin alone. The effect of reinforcement with
fibers on the properties of resin was studied, too. Thermal properties were studied
including heat distortion temperature (HDT), thermal gravimetric analysis (TGA),
erosion resistance by use of oxyacetylene burner and thermal conductivity. In
general, the results have shown that after the reinforcement with different
fibers and types of improvement factors improve the thermal properties. The
positive effect of increasing the hexamethylenetetramine is to increase most
properties of resin and its composites have shown a new case, which combines
between the other reinforcement cases i.e. the possibility of combining properties
in one material in a balanced form.
Sustainability for Tradition Cities in The Past And The Contemporary Today
Engineering and Technology Journal,
2008, Volume 26, Issue 11, Pages 450-465
This research is for general sustainable contemporary Architecture
originated from the Islamic thought and from creates a sustainable urban
environment through studding the concept of sustainability in general and
that for local one in special. Achieving dependency of traditional cities on
the comprehensive ecological approach , as all of our traditional old cities
have the advantage of sustainability, preceding modern theories in achieving
environmental and psychological integration, through meeting general
human requirements with considering convenient between physical and
spiritual sides, the most of our contemporary cities suffering lack in giving
effect to this approach .
The research depart from the comprehensive ecological approach
through attempting to explain town space system over its graduate levels,
this to indicate the differences in space systems and its influence in forming
the contemporary Urban environment structure and the losing of its permit
graduates in the comprehensive and local level, from which some
conclusions and recommendations were obtained in order to include the
sustainable concept in the design and planning processes in Architectural and
Planning work obtained from traditional Islamic Architecture .