Abstract: Theobjective of this study was to evaluate the optimal
treatment condition of Fenton oxidation process to removal
contaminant in soil slurry contaminated by petroleum hydrocarbons.
This research studied somefactors that affect the removal efficiency
of petroleum hydrocarbons in soil slurry including molar ratio of
hydrogen peroxide (H2O2) to ferrous ion(Fe2+), pH condition and
reaction time.The resultsdemonstrated that the optimum condition
was that the molar ratio of H2O2:Fe3+ was 200:1,the pHwas 4.0and
the rate of reaction was increasing rapidly from starting point to 7th
hour and destruction kinetic rate (k) was 0.24 h-1. Approximately
96% of petroleum hydrocarbon was observed(initialtotal petroleum
hydrocarbon (TPH) concentration = 70±7gkg-1)
Abstract: At present, the tendency to implement the conditionbased
maintenance (CBM), which allows the optimization of the
expenses for equipment monitoring, is more and more evident; also,
the transformer substations with remote monitoring are increasingly
used. This paper reviews all the advantages of the on-line monitoring
and presents an equipment for on-line monitoring of bushings, which
is the own contribution of specialists who are the authors of this
paper. The paper presents a study of the temperature field, using the
finite element method. For carrying out this study, the 3D modelling
of the above mentioned bushing was performed. The analysis study is
done taking into account the extreme thermal stresses, focusing at the
level of the first cooling wing section of the ceramic insulator. This
fact enables to justify the tanδ variation in time, depending on the
transformer loading and the environmental conditions. With a view
to reducing the variation of dielectric losses in bushing insulation, the
use of ferrofuids instead of mineral oils is proposed.
Abstract: Fick's second law equations for unsteady state
diffusion of salt into the potato tissues were solved numerically. The
set of equations resulted from implicit modeling were solved using
Thomas method to find the salt concentration profiles in solid phase.
The needed effective diffusivity and equilibrium distribution
coefficient were determined experimentally. Cylindrical samples of
potato were infused with aqueous NaCl solutions of 1-3%
concentrations, and variations in salt concentrations of brine were
determined over time. Solute concentrations profiles of samples were
determined by measuring salt uptake of potato slices. For the studied
conditions, equilibrium distribution coefficients were found to be
dependent on salt concentrations, whereas the effective diffusivity
was slightly affected by brine concentration.
Abstract: Adhesion strength of exterior or interior coating of
steel pipes is too important. Increasing of coating adhesion on
surfaces can increase the life time of coating, safety factor of
transmitting line pipe and decreasing the rate of corrosion and costs.
Preparation of steel pipe surfaces before doing the coating process is
done by shot and grit blasting. This is a mechanical way to do it.
Some effective parameters on that process, are particle size of
abrasives, distance to surface, rate of abrasive flow, abrasive physical
properties, shapes, selection of abrasive, kind of machine and its
power, standard of surface cleanness degree, roughness, time of
blasting and weather humidity. This search intended to find some
better conditions which improve the surface preparation, adhesion
strength and corrosion resistance of coating. So, this paper has
studied the effect of varying abrasive flow rate, changing the
abrasive particle size, time of surface blasting on steel surface
roughness and over blasting on it by using the centrifugal blasting
machine. After preparation of numbers of steel samples (according to
API 5L X52) and applying epoxy powder coating on them, to
compare strength adhesion of coating by Pull-Off test. The results
have shown that, increasing the abrasive particles size and flow rate,
can increase the steel surface roughness and coating adhesion
strength but increasing the blasting time can do surface over blasting
and increasing surface temperature and hardness too, change,
decreasing steel surface roughness and coating adhesion strength.
Abstract: This paper presents the utilizing of ferroelectric
material on antenna application. There are two different ferroelectric
had been used on the proposed antennas which include of Barium
Strontium Titanate (BST) and Bismuth Titanate (BiT), suitable for
Access Points operating in the WLAN IEEE 802.11 b/g and WiMAX
IEEE 802.16 within the range of 2.3 GHz to 2.5 GHz application.
BST, which had been tested to own a dielectric constant of εr = 15
while BiT has a dielectric constant that higher than BST which is εr =
21 and both materials are in rectangular shaped. The influence of
various parameters on antenna characteristics were investigated
extensively using commercial electromagnetic simulations software
by Communication Simulation Technology (CST). From theoretical
analysis and simulation results, it was demonstrated that ferroelectric
material used have not only improved the directive emission but also
enhanced the radiation efficiency.
Abstract: Nurses in an Armed Force Hospital (AFH) expose to stronger stress than those in a civil hospital, especially in an emergency department (ED). Ironically, stresses of these nurses received few if any attention in academic research in the past. This study collects 227 samples from the emergency departments of four armed force hospitals in central and southern Taiwan. The research indicates that the top five stressors are a massive casualty event, delayed physician support, overloads of routine work, overloads of assignments, and annoying paper work. Excessive work loading was found to be the primary source of stress. Nurses who were perceived to have greater stress levels were more inclined to deploy emotion-oriented approaches and more likely to seek job rotations. Professional stressors and problem-oriented approaches were positively correlated. Unlike other local studies, this study concludes that the excessive work-loading is more stressful in an AFH.
Abstract: Extracellular ubiquitin in vivo effect on regenerative liver cells and liver histoarchitectonics has been studied. Experiments were performed on mature female white rats. Partial hepatectomy was made using the modified method of Higgins and Anderson. Standard histopathological assessment of liver tissue was used. Proliferative activity of hepatocytes was analyzed by colchicine mitotic index and immunohistochemical staining on ki67. We have found that regardless of number of injections and dose of extracellular ubiquitin liver histology has not been changed, so at tissue level no effect was observed. In vivo double injection of ubiquitin significantly decreases the mitotic activity at 32 hour point after partial hepatectomy. Thus, we can conclude that in vivo injected extracellular ubiquitin inhibits proliferative activity of hepatocytes in partially hepatectomyzed rats.
Abstract: Effect of high temperature exposure on properties of cement mortar containing municipal solid waste incineration (MSWI) bottom ash as partial natural aggregate replacement is analyzed in the paper. The measurements of mechanical properties, bulk density, matrix density, total open porosity, sorption and desorption isotherms are done on samples exposed to the temperatures of 20°C to 1000°C. TGA analysis is performed as well. Finally, the studied samples are analyzed by IR spectroscopy in order to evaluate TGA data.
Abstract: A high performance thin layer chromatography
system (HPTLC) for the separation of vitamin B2 and B12 has been
developed. The separation was successfully using a solvent system of
methanol, water, ammonia 7.3.1 (V/V) as mobile phase on HPTLC
plates impregnated with boric acid. The effect of other mobile phases
on the separation of vitamins was also examined. The method is
based on different behavior of investigated compounds in
impregnated TLC plates with different amount of boric acid. The Rf
values of vitamin B2 and B12 are considered on non impregnated
and impregnated silica gel HPTLC plate with boric acid. The effect
of boric acid in the mobile phase and on HPTLC plates on the RF
values of the vitamins has also been studied.
Abstract: In designing river intakes and diversion structures, it is paramount that the sediments entering the intake are minimized or, if possible, completely separated. Due to high water velocity, sediments can significantly damage hydraulic structures especially when mechanical equipment like pumps and turbines are used. This subsequently results in wasting water, electricity and further costs. Therefore, it is prudent to investigate and analyze the performance of lateral intakes affected by sediment control structures. Laboratory experiments, despite their vast potential and benefits, can face certain limitations and challenges. Some of these include: limitations in equipment and facilities, space constraints, equipment errors including lack of adequate precision or mal-operation, and finally, human error. Research has shown that in order to achieve the ultimate goal of intake structure design – which is to design longlasting and proficient structures – the best combination of sediment control structures (such as sill and submerged vanes) along with parameters that increase their performance (such as diversion angle and location) should be determined. Cost, difficulty of execution and environmental impacts should also be included in evaluating the optimal design. This solution can then be applied to similar problems in the future. Subsequently, the model used to arrive at the optimal design requires high level of accuracy and precision in order to avoid improper design and execution of projects. Process of creating and executing the design should be as comprehensive and applicable as possible. Therefore, it is important that influential parameters and vital criteria is fully understood and applied at all stages of choosing the optimal design. In this article, influential parameters on optimal performance of the intake, advantages and disadvantages, and efficiency of a given design are studied. Then, a multi-criterion decision matrix is utilized to choose the optimal model that can be used to determine the proper parameters in constructing the intake.
Abstract: In the present paper; an experimental and numerical
investigations of drag reduction on a grooved circular cylinder have
been performed. The experiments were carried out in closed circuit
subsonic wind tunnel (TE44); the pressure distribution on the
cylinder was conducted using a TE44DPS differential pressure
scanner and the drag forces were measured using the TE81 balance.
The display unit is linked to a computer, loaded with DATASLIM
software for data analysis and logging of result. The numerical study
was performed using the code ANSYS FLUENT solving the
Reynolds Averaged Navier-Stokes (RANS) equations. The k-ε and k-
ω SST models were tested. The results obtained from the
experimental and numerical investigations have showed a reduction
in the drag when using longitudinal grooves namely 2 and 6 on the
cylinder.
Abstract: Borate minerals have attracted considerable attention in the past years due to their structural chemistry and mechanical properties in several industries. Recently, increasing attention has been paid to the use of; synthetically produced magnesium borates as catalysts reinforcing material for plastics, the conversion of hydrocarbons, electro-conductive treating agent, anti-wear and anti-corrosion materials. Magnesium borates can be synthesized by several methods such as; hydrothermal and solid-state (thermal) processes. In this study the hydrothermal production method was applied at the modest temperature of 80C along with convenient crystal growth. Using MgCl2.6H2O, H3BO3, and NaOH as starting materials, 30, 60, 120, 240 minutes of reaction times were studied. After all, the crystal structure and the morphology of the products were examined by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). As a result the forms of Admontite and Mcallisterite minerals were synthesized.
Abstract: Stress analysis of functionally graded composite plates
composed of ceramic, functionally graded material and metal layers is
investigated using 3-D finite element method. In FGM layer, material
properties are assumed to be varied continuously in the thickness
direction according to a simple power law distribution in terms of the
volume fraction of a ceramic and metal. The 3-D finite element model
is adopted by using an 18-node solid element to analyze more
accurately the variation of material properties in the thickness
direction. Numerical results are compared for three types of materials.
In the analysis, the tensile and the compressive stresses are
summarized for various FGM thickness ratios, volume fraction
distributions, geometric parameters and mechanical loads.
Abstract: This paper presents the results of an experimental study on the performance of a triboelectric separator of plastic mixtures used for recycling. The separator consists of four cylindrical electrodes. The principle behind the separation technique is based on the difference in the Coulomb force acting on the plastic particles after triboelectric charging. The separation of mixtures of acrylonitrile butadiene styrene (ABS) and polystyrene (PS) using this method was studied. The effects of the triboelectric charging time and applied voltage on the separation efficiency were investigated. The experimental results confirm that it is possible to obtain a high purity and recovery rate for the initial compositions considered in this study.
Abstract: The aim of this work is to study the elastic transfer
phenomenon which takes place in the elastic scattering of 16O on 12C
at energies near the Coulomb barrier. Where, the angular distribution
decrease steadily with increasing the scattering angle, then the cross
section will increase at backward angles due to the α-transfer process.
This reaction was also studied at different energies for tracking the
nuclear rainbow phenomenon. The experimental data of the angular
distribution at these energies were compared to the calculation
predictions. The optical potential codes such as SPIVAL and
Distorted Wave Born Approximation (DWUCK5) were used in
analysis.
Abstract: Utilization of bagasse ash for silica sources is one of
the most common application for agricultural wastes and valuable
biomass byproducts in sugar milling. The high percentage silica
content from bagasse ash was used as silica source for sodium
silicate solution. Different heating temperature, time and acid
treatment were studies for silica extraction. The silica was
characterized using various techniques including X-ray fluorescence,
X-ray diffraction, Scanning electron microscopy, and Fourier
Transform Infrared Spectroscopy method,. The synthesis conditions
were optimized to obtain the bagasse ash with the maximum silica
content. The silica content of 91.57 percent was achieved from
heating of bagasse ash at 600°C for 3 hours under oxygen feeding
and HCl treatment. The result can be used as value added for bagasse
ash utilization and minimize the environmental impact of disposal
problems.
Abstract: Pentachlorophenol (PCP) is a polychlorinated
aromatic compound that is widespread in industrial effluents and is
considered to be a serious pollutant. Among the variety of industrial
effluents encountered, effluents from tanning industry are very
important and have a serious pollution potential. PCP is also formed
unintentionally in effluents of paper and pulp industries. It is highly
persistent in soils and is lethal to a wide variety of beneficial
microorganisms and insects, human beings and animals. The natural
processes that breakdown toxic chemicals in the environment have
become the focus of much attention to develop safe and environmentfriendly
deactivation technologies. Microbes and plants are among
the most important biological agents that remove and degrade waste
materials to enable their recycling in the environment. The present
investigation was carried out with the aim of developing a microbial
system for bioremediation of PCP polluted soils. A number of plant
species were evaluated for their ability to tolerate different
concentrations of pentachlorophenol (PCP) in the soil. The
experiment was conducted for 30 days under pot culture conditions.
The toxic effect of PCP on plants was studied by monitoring seed
germination, plant growth and biomass. As the concentration of PCP
was increased to 50 ppm, the inhibition of seed germination, plant
growth and biomass was also increased. Although PCP had a
negative effect on all plant species tested, maize and groundnut
showed the maximum tolerance to PCP. Other tolerating crops
included wheat, safflower, sunflower, and soybean. From the
rhizosphere soil of the tolerant seedlings, as many as twenty seven
PCP tolerant bacteria were isolated. From soybean, 8; sunflower, 3;
safflower 8; maize 2; groundnut and wheat, 3 each isolates were
made. They were screened for their PCP degradation potentials.
HPLC analyses of PCP degradation revealed that the isolate MAZ-2
degraded PCP completely. The isolate MAZ-1 was the next best
isolate with 90 per cent PCP degradation. These strains hold promise
to be used in the bioremediation of PCP polluted soils.
Abstract: For gamma radiation detection, assemblies having
scintillation crystals and a photomultiplier tube, also there is a
preamplifier connected to the detector because the signals from
photomultiplier tube are of small amplitude. After pre-amplification
the signals are sent to the amplifier and then to the multichannel
analyser. The multichannel analyser sorts all incoming electrical
signals according to their amplitudes and sorts the detected photons
in channels covering small energy intervals. The energy range of
each channel depends on the gain settings of the multichannel
analyser and the high voltage across the photomultiplier tube. The
exit spectrum data of the two main isotopes studied ,putting data in
biomass program ,process it by Matlab program to get the solid
holdup image (solid spherical nuclear fuel)
Abstract: The objective of global optimization is to find the
globally best solution of a model. Nonlinear models are ubiquitous
in many applications and their solution often requires a global
search approach; i.e. for a function f from a set A ⊂ Rn to
the real numbers, an element x0 ∈ A is sought-after, such that
∀ x ∈ A : f(x0) ≤ f(x). Depending on the field of application,
the question whether a found solution x0 is not only a local minimum
but a global one is very important.
This article presents a probabilistic approach to determine the
probability of a solution being a global minimum. The approach is
independent of the used global search method and only requires a
limited, convex parameter domain A as well as a Lipschitz continuous
function f whose Lipschitz constant is not needed to be known.
Abstract: Chicken feathers were used as biosorbent for Pb
removal from aqueous solution. In this paper, the kinetics and
equilibrium studies at several pH, temperature, and metal
concentration values are reported. For tested conditions, the Pb
sorption capacity of this poultry waste ranged from 0.8 to 8.3 mg/g.
Optimal conditions for Pb removal by chicken feathers have been
identified. Pseudo-first order and pseudo-second order equations
were used to analyze the experimental data. In addition, the sorption
isotherms were fitted to classical Langmuir and Freundlich models.
Finally, thermodynamic parameters for the sorption process have
been determined. In summary, the results showed that chicken
feathers are an alternative and promising sorbent for the treatment of
effluents polluted by Pb ions.