Abstract: The recovery of metal values and safe disposal of
spent catalyst is gaining interest due to both its hazardous nature and
increased regulation associated with disposal methods. Prior to the
recovery of the valuable metals, removal of entrained deposits limit
the diffusion of lixiviate resulting in low recovery of metals must be
taken into consideration. Therefore, petroleum refinery spent catalyst
was subjected to acetone washing and roasting at 500oC. The treated
samples were investigated for metals bioleaching using
Acidithiobacillus ferrooxidans in batch reactors and the leaching
efficiencies were compared. It was found out that acetone washed
spent catalysts results in better metal recovery compare to roasted
spent. About 83% Ni, 20% Al, 50% Mo and 73% V were leached
using the acetone washed spent catalyst. In both the cases, Ni, V and
Mo was high compared to Al.
Abstract: We focus on the excitation and propagation properties
of surface plasmon polariton (SPP). We have developed a SPP
excitation device in combination with a grating structures fabricated
by using the scanning probe lithography. Perturbation approach was
used to investigate the coupling properties of SPP with a spatial
harmonic wave supported by a metallic grating. A phase shift grating
SPP coupler has been fabricated and the optical property was
evaluated by the Fraunhofer diffraction formula. We have been
experimentally confirmed the induced stop band by diffraction
measurement. We have also observed the wavenumber shift of the
resonance condition of SPP owing to effect of a phase shift.
Abstract: During recent years, attention in 'Green Computing'
has moved research into energy-saving techniques for home
computers to enterprise systems' Client and Server machines. Saving
energy or reduction of carbon footprints is one of the aspects of
Green Computing. The research in the direction of Green Computing
is more than just saving energy and reducing carbon foot prints. This
study provides a brief account of Green Computing. The emphasis of
this study is on current trends in Green Computing; challenges in the
field of Green Computing and the future trends of Green Computing.
Abstract: There are several means to measure the oxidation of edible oils, such as the acid value, the peroxide value, and the anisidine value. However, these means require large quantities of reagents and are time-consuming tasks. Therefore, a more convenient and time-saving way to measure the oxidation of edible oils is required. In this report, an edible oil condition sensor was fabricated by using single-walled nanotubes (SWNT). In order to test the sensor, oxidized edible oils, each one at a different acid value, were prepared. The SWNT sensors were immersed into these oxidized oils and the resistance changes in the sensors were measured. It was found that the conductivity of the sensors decreased as the oxidation level of oil increased. This result suggests that a change of the oil components induced by the oxidation process in edible oils is related to the conductivity change in the SWNT sensor.
Abstract: Optimizing equipment selection in heavy earthwork
operations is a critical key in the success of any construction project.
The objective of this research incentive was geared towards
developing a computer model to assist contractors and construction
managers in estimating the cost of heavy earthwork operations.
Economical operation analysis was conducted for an equipment fleet
taking into consideration the owning and operating costs involved in
earthwork operations. The model is being developed in a Microsoft
environment and is capable of being integrated with other estimating
and optimization models. In this study, Caterpillar® Performance
Handbook [5] was the main resource used to obtain specifications of
selected equipment. The implementation of the model shall give
optimum selection of equipment fleet not only based on cost
effectiveness but also in terms of versatility. To validate the model, a
case study of an actual dam construction project was selected to
quantify its degree of accuracy.
Abstract: Bone marrow-derived stem cells have been widely
studied as an alternative source of stem cells. Mesenchymal stem
cells (MSCs) were mostly investigated and studies showed MSCs can
promote neurogenesis. Little is known about the non-mesenchymal
mononuclear cell fraction, which contains both hematopoietic and
nonhematopoietic cells, including monocytes and endothelial
progenitor cells. This study focused on unfractionated bone marrow
mononuclear cells (BMMCs), which remained 72 h after MSCs were
adhered to the culture plates. We showed that BMMC-conditioned
medium promoted morphological changes of human SH-SY5Y
neuroblastoma cells from an epithelial-like phenotype towards a
neuron-like phenotype as indicated by an increase in neurite
outgrowth, like those observed in retinoic acid (RA)-treated cells.
The result could be explained by the effects of trophic factors
released from BMMCs, as shown in the RT-PCR results that
BMMCs expressed nerve growth factor (NGF), brain-derived
neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF).
Similar results on the cell proliferation rate were also observed
between RA-treated cells and cells cultured in BMMC-conditioned
medium, suggesting that cells creased proliferating and differentiated
into a neuronal phenotype. Using real-time RT-PCR, a significantly
increased expression of tyrosine hydroxylase (TH) mRNA in SHSY5Y
cells indicated that BMMC-conditioned medium induced
catecholaminergic identities in differentiated SH-SY5Y cells.
Abstract: This paper tests the level of market integration between Malaysia and Singapore stock markets with the world market. Kalman Filter (KF) methodology is used on the International Capital Asset Pricing Model (ICAPM) and the pricing errors estimated within the framework of ICAPM are used as a measure of market integration or segmentation. The advantage of the KF technique is that it allows for time-varying coefficients in estimating ICAPM and hence able to capture the varying degree of market integration. Empirical results show clear evidence of varying degree of market integration for both case of Malaysia and Singapore. Furthermore, the results show that the changes in the level of market integration are found to coincide with certain economic events that have taken placed. The findings certainly provide evidence on the practicability of the KF technique to estimate stock markets integration. In the comparison between Malaysia and Singapore stock market, the result shows that the trends of the market integration indices for Malaysia and Singapore look similar through time but the magnitude is notably different with the Malaysia stock market showing greater degree of market integration. Finally, significant evidence of varying degree of market integration shows the inappropriate use of OLS in estimating the level of market integration.
Abstract: The effects of dynamic subgrid scale (SGS) models are
investigated in variational multiscale (VMS) LES simulations of bluff
body flows. The spatial discretization is based on a mixed finite
element/finite volume formulation on unstructured grids. In the VMS
approach used in this work, the separation between the largest and the
smallest resolved scales is obtained through a variational projection
operator and a finite volume cell agglomeration. The dynamic version
of Smagorinsky and WALE SGS models are used to account for
the effects of the unresolved scales. In the VMS approach, these
effects are only modeled in the smallest resolved scales. The dynamic
VMS-LES approach is applied to the simulation of the flow around a
circular cylinder at Reynolds numbers 3900 and 20000 and to the flow
around a square cylinder at Reynolds numbers 22000 and 175000. It
is observed as in previous studies that the dynamic SGS procedure
has a smaller impact on the results within the VMS approach than in
LES. But improvements are demonstrated for important feature like
recirculating part of the flow. The global prediction is improved for
a small computational extra cost.
Abstract: This paper presents the development of low cost Nano membrane fabrication system. The system is specially designed for anodic aluminum oxide membrane. This system is capable to perform the processes such as anodization and electro-polishing. The designed machine was successfully tested for 'mild anodization' (MA) for 48 hours and 'hard anodization' (HA) for 3 hours at constant 0oC. The system is digitally controlled and guided for temperature maintenance during anodization and electro-polishing. The total cost of the developed machine is 20 times less than the multi-cooling systems available in the market which are generally used for this purpose.
Abstract: This research study the application of the immobilized
TiO2 layer and Cu-TiO2 layer on graphite substrate as a negative
electrode or anode for Li-ion battery. The titania layer was produced
through chemical bath deposition method, meanwhile Cu particles
were deposited electrochemically. A material can be used as an
electrode as it has capability to intercalates Li ions into its crystal
structure. The Li intercalation into TiO2/Graphite and Cu-
TiO2/Graphite were analyzed from the changes of its XRD pattern
after it was used as electrode during discharging process. The XRD
patterns were refined by Le Bail method in order to determine the
crystal structure of the prepared materials. A specific capacity and the
cycle ability measurement were carried out to study the performance
of the prepared materials as negative electrode of the Li-ion battery.
The specific capacity was measured during discharging process from
fully charged until the cut off voltage. A 300 was used as a load.
The result shows that the specific capacity of Li-ion battery with
TiO2/Graphite as negative electrode is 230.87 ± 1.70mAh.g-1 which is
higher than the specific capacity of Li-ion battery with pure graphite
as negative electrode, i.e 140.75 ±0.46mAh.g-1. Meanwhile
deposition of Cu onto TiO2 layer does not increase the specific
capacity, and the value even lower than the battery with
TiO2/Graphite as electrode. The cycle ability of the prepared battery
is only two cycles, due to the Li ribbon which was used as cathode
became fragile and easily broken.
Abstract: The complexity of lignocellulosic biomass requires
a pretreatment step to improve the yield of fermentable sugars. The
efficient pretreatment of corn cobs using microwave and potassium
hydroxide and enzymatic hydrolysis was investigated. The
objective of this work was to characterize the optimal condition of
pretreatment of corn cobs using microwave and potassium
hydroxide enhance enzymatic hydrolysis. Corn cobs were
submerged in different potassium hydroxide concentration at varies
temperature and resident time. The pretreated corn cobs were
hydrolyzed to produce the reducing sugar for analysis. The
morphology and microstructure of samples were investigated by
Thermal gravimetric analysis (TGA, scanning electron microscope
(SEM), X-ray diffraction (XRD). The results showed that lignin
and hemicellulose were removed by microwave/potassium
hydroxide pretreatment. The crystallinity of the pretreated corn
cobs was higher than the untreated. This method was compared
with autoclave and conventional heating method. The results
indicated that microwave-alkali treatment was an efficient way to
improve the enzymatic hydrolysis rate by increasing its
accessibility hydrolysis enzymes.
Abstract: Mercury is a natural occurring element and present in
various concentrations in the environment. Due to its toxic effects, it
is desirable to research mercury sensitive materials to adsorb
mercury. This paper describes the preparation of Au nanoparticles for
mercury adsorption by using a microwave (MW)-polyol method in
the presence of three different Sodium Chloride (NaCl)
concentrations (10, 20 and 30 mM). Mixtures of spherical, triangular,
octahedral, decahedral particles and 1-D product were obtained using
this rapid method. Sizes and shapes was found strongly depend on the
concentrations of NaCl. Without NaCl concentration, spherical,
triangular plates, octahedral, decahedral nanoparticles and 1D
product were produced. At the lower NaCl concentration (10 mM),
spherical, octahedral and decahedral nanoparticles were present,
while spherical and decahedral nanoparticles were preferentially form
by using 20 mM of NaCl concentration. Spherical, triangular plates,
octahedral and decahedral nanoparticles were obtained at the highest
NaCl concentration (30 mM). The amount of mercury adsorbed using
20 ppm mercury solution is the highest (67.5 %) for NaCl
concentration of 30 mM. The high yield of polygonal particles will
increase the mercury adsorption. In addition, the adsorption of
mercury is also due to the sizes of the particles. The sizes of particles
become smaller with increasing NaCl concentrations (size ranges, 5-
16 nm) than those synthesized without addition of NaCl (size ranges
11-32 nm). It is concluded that NaCl concentrations affects the
formation of sizes and shapes of Au nanoparticles thus affects the
mercury adsorption.
Abstract: School homework has been synonymous with students- life in Chinese national type primary schools in Malaysia. Although many reports in the press claimed that students were burdened with too much of it, homework continues to be a common practice in national type schools that is believed to contribute to academic achievement. This study is conducted to identify the relationship between the burden of school homework and academic achievement among pupils in Chinese National Type Primary School in the state of Perak, Malaysia. A total of 284 students (142 from urban and 142 from rural) respectively were chosen as participants in this study. Variables of gender and location (urban/rural areas) has shown significant difference in student academic achievement. Female Chinese student from rural areas showed a higher mean score than males from urban area. Therefore, the Chinese language teachers should give appropriate and relevant homework to primary school students to achieve good academic performance.
Abstract: New nondestructive technique, namely an inverse technique based on vibration tests, to characterize nonlinear mechanical properties of adhesive layers in sandwich composites is developed. An adhesive layer is described as a viscoelastic isotropic material with storage and loss moduli which are both frequency dependent values in wide frequency range. An optimization based on the planning of experiments and response surface technique to minimize the error functional is applied to decrease considerably the computational expenses. The developed identification technique has been tested on aluminum panels and successfully applied to characterize viscoelastic material properties of 3M damping polymer ISD-112 used as a core material in sandwich panels.
Abstract: Before performing polymerase chain reactions (PCR), a feasible primer set is required. Many primer design methods have been proposed for design a feasible primer set. However, the majority of these methods require a relatively long time to obtain an optimal solution since large quantities of template DNA need to be analyzed. Furthermore, the designed primer sets usually do not provide a specific PCR product. In recent years, evolutionary computation has been applied to PCR primer design and yielded promising results. In this paper, a particle swarm optimization (PSO) algorithm is proposed to solve primer design problems associated with providing a specific product for PCR experiments. A test set of the gene CYP1A1, associated with a heightened lung cancer risk was analyzed and the comparison of accuracy and running time with the genetic algorithm (GA) and memetic algorithm (MA) was performed. A comparison of results indicated that the proposed PSO method for primer design finds optimal or near-optimal primer sets and effective PCR products in a relatively short time.
Abstract: The mathematical modeling of storm surge in sea and
coastal regions such as the South China Sea (SCS) and the Gulf of
Thailand (GoT) are important to study the typhoon characteristics.
The storm surge causes an inundation at a lateral boundary exhibiting
in the coastal zones particularly in the GoT and some part of the SCS.
The model simulations in the three dimensional primitive equations
with a high resolution model are important to protect local properties
and human life from the typhoon surges. In the present study, the
mathematical modeling is used to simulate the typhoon–induced
surges in three case studies of Typhoon Linda 1997. The results
of model simulations at the tide gauge stations can describe the
characteristics of storm surges at the coastal zones.
Abstract: An experiment was conducted to determine the effect
of the rearing system on growth performance, carcass yield,
hematological parameters, and feather pecking damage of Thai
indigenous chickens. Three hundred and sixty 1-d-old chicks were
randomly assigned to 2 treatments: indoor treatment and outdoor
access treatment. In the indoor treatment, the chickens were housed
in floor pens (5 birds/m2). In the outdoor access treatment, the
chickens were housed in a similar indoor house; in addition, they also
had an outdoor grass paddock (1 bird/m2). All birds were provided
with same diet and were raised for 16 wk of age. The results showed
that growth performance and carcass yield were not different among
treatment (P>0.05). Outdoor access had no effect on hematological
parameters (P>0.05). However, the feather pecking damage of the
chickens in the outdoor access treatment was lower than that of the
chickens in the indoor treatment (P
Abstract: This paper presents a new ultra-wideband (UWB) bandpass filter (BPF) with sharp roll-off and dual-notched bands. The filter consists of a triangle ring multi-mode resonator (MMR) with the stub-loaded resonator (SLR) for controlling the two transmission zeros at 2.8 / 11 GHz, the embedded open-circuited stub and the asymmetric tight coupled input/output (I/O) lines for introducing the dual notched bands at 5.2 / 6.8 GHz. The attenuation slope in the lower and higher passband edges of the proposed filter show 160- and 153-dB/GHz, respectively. This study mainly provides a simple method to design a UWB bandpass filter with high passband selectivity and dual-notched bands for satisfying the Federal Communications Commission (FCC-defined) indoor UWB specification
Abstract: This paper deals with a delayed single population model on time scales. With the assistance of coincidence degree theory, sufficient conditions for existence of periodic solutions are obtained. Furthermore, the better estimations for bounds of periodic solutions are established.
Abstract: Theory of Constraints has been emerging as an
important tool for optimization of manufacturing/service systems.
Goldratt in his first book “ The Goal " gave the introduction on
Theory of Constraints and its applications in a factory scenario. A
large number of production managers around the globe read this book
but only a few could implement it in their plants because the book did
not explain the steps to implement TOC in the factory. To overcome
these limitations, Goldratt wrote this book to explain TOC, DBR and
the method to implement it. In this paper, an attempt has been made
to summarize the salient features of TOC and DBR listed in the book
and the correct approach to implement TOC in a factory setting. The
simulator available along with the book was actually used by the
authors and the claim of Goldratt regarding the use of DBR and
Buffer management to ease the work of production managers was
tested and was found to be correct.