In this study, the corn stalk (CS) had been utilized as natural filler in low density polyethylene (LDPE). The effect of CS
loading and coconut oil coupling agent (COCA) on tensile, thermal and water absorption properties of LDPE/CS composites
were investigated. The increases of CS decreased the tensile strength and elongation at break of LDPE/CS composites, but
increased in Young’s modulus. The incorporation of CS also contributed to high water uptake of LDPE/CS composites.
However, the presence of CS has increased the crystallinity of composites and LDPE matrix due to nucleating effect. The
addition of COCA has significantly increased the tensile strength, elongation at break, water resistivity and crystallinity
of LDPE/CS composites, but slightly reduced in Young’s modulus. The scanning electron microscope (SEM) also evidence
the presence of COCA improved the adhesion between CS and LDPE matrix.
The aim of this research was to synthesize zeolite from coal fly ash by hydrothermal method. The effect of aging temperature
and time on zeolite P1 synthesis (Na-P1) from Mae Moh coal fly ash (MFA) without adding any alumina and silica sources
were examined during the synthesized process. The central composite design (CCD) was used for experimental design
to obtain the optimal process parameters of the aging temperature (105-195ºC) and time (12-84 h) where the specific
surface area was used as a response. The chemical and physical properties of Na-P1 such as specific surface area,
crystalline phase, compositions and morphology were examined. The response results showed that the specific surface
area of Na-P1 decreased with an increase of both aging temperature and time, whereas the XRD intensity of Na-P1
increased with an increase of both aging temperature and time. The composition of SiO2
in mass ratio of coal fly
ash was observed, which was suitable to Na-P1 synthesis. The maximum specific surface area of zeolite products was
found at the designed condition of aging temperature of 105ºC and time of 12 h. Thus, zeolite P1 can be prepared by
hydrothermal method without adding any alumina and silica sources.
This paper reports the preparation of the dual layer ceramic hollow fiber membrane that made of alumina and a mixed
ion electron conducting (MIEC) material for simultaneous reaction and separation applications. Alumina hollow fiber
membrane was prepared using the phase inversion process followed by a sintering technique at elevated temperature. The
alumina hollow fiber membrane was used as membrane support onto which a thin and dense layer of lanthanum strontium
cobalt ferrite (LSCF) was deposited. The main objective of this study was to investigate the LSCF coating formulations
used in the deposition of LSCF layer onto alumina substrate membrane. The sintering temperature of thin LSCF layer was
varied to investigate gas-tightness properties of LSCF membrane. A series of characterizations were conducted for both
the support and the LSCF membrane. The result showed that the thin layer membranes with thicknesses ranging from 3
to 20 µm were successfully deposited on the surface of alumina hollow fiber support. The sintering process improved the
gas-tightness properties but the sintering temperature above 1150o
C caused defects on the surface of LSCF membrane.
The increasing demands of natural gas pushes energy industries to explore the reservoirs contain high CO2 concentration
and impurities including heavy hydrocarbons. High efficiency of using membrane technology in CO2
-natural gas separation
has extended its potential application to offshore environment. Due to the limited studies related with the separation of
under offshore conditions, the present work has investigated the separation performance of a commercial membrane
in removing bulk CO2
from methane at elevated pressure condition. A wide range of offshore operating conditions
including pressure from 10 to 50 bar, CO2
concentration from 25 to 70% and temperature of 30o
C and 50o
studied. High relative CO2 permeance and relative CO2
selectivity were observed when the pressure and the CO2
concentration increased. This work, therefore substantial is to bridge the gap and facilitates the application of membrane
technology for offshore operating conditions.
The composite polymer electrolytes (CPEs) composed of polyacrylonitrile (PAN) as host polymer, lithium tetraflouroborate
) as dopant salt, dissoÅlved in the mixture of ethylene carbonate (EC) and dimethyl phthalate (DMP) as plasticizing
solvent, with the addition of silica (SiO2
) as inorganic filler were prepared by the solution casting technique. The CPE films
were prepared by varying the concentrations of SiO2
from 1 to 5 wt. %. The CPE film containing 3 wt. % of SiO2 exhibits
the highest ionic conductivity of 1.36 × 10-2 S cm-1 at room temperature while for temperature dependence studies, the
plot obtained obeyed Arrhenius rule and the calculated activation energy was 0.11 eV. The ionic conductivity of the CPEs
was found to depend on the concentration of ion pairs of dopant salt as showed by FTIR spectra. The calculated value of
lithium ions transport number, tLi+ for the highest conducting CPE film was 0.15. This result indicates that anionic species
are the main contributor to the total conductivity of the CPE. The CPE film has an electrochemical stability higher than
the non-filler film.
The development of a non-thermal plasma jet with a capillary configuration working at atmospheric pressure is reported
in this paper. The plasma jet is powered by a power source with frequency of several kilohertz. The working gas is
argon. The plasma obtained has been characterized by optical emission spectroscopic measurements and electrical
measurements of the discharge using voltage and current probes. The electron temperature has been estimated by using
the modified Boltzmann plot method utilizing the Ar 4p-4s transition. The electron temperatures at various positions
along the plasma jet length have been obtained and it is found that the electron temperature decreases at position further
from orifice. The electron density has been estimated from current and voltage measurements using the power balance
method. The effects of gas flow rate, applied voltage and frequency on the characteristics of the plasma jet have also been
investigated. The applications of the atmospheric pressure plasma jet (APPJ) developed to modify the surface properties
of Polyethyleneterephthalate (PET) and polycarbonate (PC) have been tested. Our results showed that the atmospheric
pressure non-thermal plasma jet can be effectively used to enhance the surface wettability and surface energy of the
PET and PC. The plasma jet has also been tested for inactivation of prokaryotic cells (Escherichia coli, Staphylococcus
aureus). In the case of E. coli, better than 4 log10 reduction can be achieved. The effect of plasma jet on the pH of cell
culture medium has suggested that the plasma species, particularly the electrons, are solely responsible for the effect
of inactivation of living cells.
Titanium dioxide (TiO2
) nanorods and nanoparticles had been successfully done by hydrothermal method and spray
pyrolysis deposition technique, respectively. Form XRD results, crystallite structure for TiO2
nanorods is rutile phase
at 2θ degree 27.5° which corresponded to  orientation. Whereas, TiO2
nanoparticles produced anatase phase at
2θ degree 25.3° which corresponded to  plane. The structure of nanorods and nanoparticles were characterized
using FESEM. The size of nanorods was in the range of 80 to 100 nm. While, the nanoparticles size was ranging from
25 to 35 nm. The HeLa cells were grown on those TiO2
and were observed under fluorescence microscope. The cells
showed healthy sign of growth on TiO2
nanorods and nanoparticles substrates. Thus, TiO2
nanorods and nanoparticles
are biocompatible to HeLa cells.
Titanium dioxide (TiO2
) with various morphologies has been successfully synthesized by a simple hydrothermal method
C for 10 h using titanium butoxide (TBOT) as a precursor, deionized (DI) water and hydrochloric acid (HCl) on
a fluorine-doped tin oxide (FTO) substrate. The influences of HCl volume on structural and morphological properties
have been studied using x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM),
respectively. The result showed that several morphologies such as microsphere, microrods, nanorods and nanoflowers
were obtained by varying the volume of hydrochloric acid. The crystallinity of titanium dioxide enhanced with the
increasing of hydrochloric acid volume.
Incorporation of silver nanomaterial into polymer matrix can further accomplished their potential usage in real life
applications. In our previous study, silver nanoparticles (AgNPs) and silver-graphene oxide nanocomposites (AgGO)
were prepared via a rapid microwave-assisted method. Hereby, the as-synthesized AgNPs or AgGO was dispersed in a
chitosan solution. Subsequently, the resultant mixture solution was further coagulated in a coagulation bath containing
sodium hydroxide via a neutralization process. This resulted in the formation of spherical-shaped chitosan beads.
The structure of the beads showed that the chitosan beads embedded with AgGO exhibited a more porous structure as
compared to the plain chitosan beads. Furthermore, the chitosan beads containing AgNPs or AgGO were tested for
their antibacterial activity against Escherichia coli and Staphylococcus aureus. The antibacterial results indicated that
the silver nanomaterial contained chitosan beads could effectively inhibit the growth of both E. coli and S. aureus as
compared to the bare chitosan beads. The produced chitosan nanocomposite envisioned that can be potentially employed
for water disinfection purpose.
This paper demonstrates the performance experiment and numerical prediction of the copper based hair cell for
underwater sensing. Generally, the hair cell consists of the single cantilever that attached perpendicular to the substrate
and integrated with strain gage (Kyowa type: KFG-1N-120-C1-11). The hair cell sensor was simulated using different
flow rates to study the pressure and the strain distribution acting on the sensor by using computational fluid dynamic
and finite element analysis approach. High performance sensor can be achieved by increasing the length of the hair cell
and also using low Young Modulus material. The hair cell has been fabricated for dimension of 8000 μm length, 2000
μm width and 100 μm thickness, where the copper was chosen due to its mechanical properties. The response time for
a sensor to respond completely to a change in input is about 50 m/s and the sensitivity in terms of output voltage and
input flow rate is 0.2 mV/ms-1. Also, the result obtained in the simulation is aligned with the experimental result. The
experiment for moving object detection proved that this sensor is able to detect the moving object and it is necessary for
underwater applications, especially for monitoring and surveillance.
Chemical and thermal properties of pure lignin are depending on the plant origin, extraction method and type of
lignocellulosic. In this study, lignin from oil palm empty fruit bunch (EFB) and kenaf core were recovered from soda black
liquor by two steps of acid precipitation with hydrochloric acid and followed by soxhlet with n-hexane. The XRD analysis
of purified EFB lignin (EAL) and purified kenaf core lignin (KAL) exhibited amorphous properties, similar to the standard
alkali lignin (SAL). The FTIR and Raman spectra showed that all samples consist of HGS unit. In FTIR, the syringyl unit is
assigned at (1125 cm-1), (1327 and 1121 cm-1) and (1326and 1117 cm-1) meanwhile the guaicyl unit is assigned at (1263,
1212 and 1028 cm-1), (1271, 1217 and 1028 cm-1) and (1270, 1211 and 1030 cm-1) for SAL, EAL and KAL, respectively.
The peak around 1160 cm-1 represents C-O stretching of conjugated ester group present in HGS lignin. As for Raman, the
HGS unit exists in the range of 1100-1400 cm-1. Among the purified samples, the TGA result showed that KAL has a better
thermal stability with the residue of 36.49% and higher Tg value which is 152.69°C.
Motor vehicle accidents are the most common cause of injuries involving avulsion of the brachial plexus in humans,
resulting in debilitating motor dysfunction. Lack of an established animal model to test drug treatments hinders
the introduction of new pharmacological agents. Avulsion injury of cervical ventral roots can be replicated in rats,
resulting in a progressive loss of the motoneurons and increase in neurotoxic expression of microglia. This is a report
on the effect of prompt nerve implantation and minocycline treatment on the suppression of microglia activation and
survival of motoneurons. 20 adult female Sprague-Dawley rats were used for this study, which was approved by the
Animal Ethical Committee, USM (approval number /2011/(73)(346)). The animals underwent surgical avulsion of the
C6 nerve root, followed by reimplantation with peripheral nerve graft and treatment with intraperitoneal minocycline.
At 6 weeks postoperatively, immunohistochemistry using primary antibody Iba1 (microglia) and nicotinamide adenine
dinucleotide phosphate diaphorase (NADPh) with neutral-red staining (motoneuron) under flourescence microscopy
was performed at the C6 spinal cord segment and then quantified. This study showed significant reduction of microglia
expression in the study group; mean ranks of control and study group were 15.2 and 11.6, respectively; U=9.5, Z=3.02,
p<0.05. However, this did not translate into a significant increase of motoneuron survival in the combined group;
the mean ranks of control and study group were 40.6 and 41.6, respectively; U=44.5, Z=-.0378, p>0.05. This may
be due to the effect of the surgery; the surgery has the potential to cause additional trauma to the cord parenchyma,
leading to further motoneuron loss and an increase in scarring around the avulsed region, thus impeding regeneration
of the motoneuron.
Fluids with different properties would exhibit different flow behaviour in any multiphase flow system at a given operating
condition. Therefore, an in-depth knowledge of the operational and flow behaviour of any known fluid properties in a
multiphase flow system of either liquid-liquid two-phase flow (oil and water) or gas-liquid-liquid three-phase flow (gas,
oil and water) would be helpful in designing of pipelines and optimization of the production, separation, transportation
and distribution systems, as may be found in oil and gas and allied petro-chemical industries. This paper presents the
experimental observation of the flow patterns and water holdup for a two-phase low viscosity oil-water flow in horizontal
pipes. The test fluids comprised of tap water and 2D-diesel which has a density of 832 kg/m3
, viscosity of 3.24 mPa.s,
surface tension of 0.030 N/m and flash point of 79°C. A total of 30 runs has been accomplished and the experimental
results showed three different flow patterns identified as stratified flow (ST), stratified flow with mixing interface (ST&MI)
and water-in-oil dispersed flow (), with superficial velocities of oil and water in the ranges of 0.32 - 0.87 m/s (Vos) and
0.20 - 0.90 m/s (Vws), respectively. However, analysis of water holdup in the commingled flows of the test fluids showed
its dependency on the fluid flow patterns and superficial velocity of water.
The air pollution index (API) has been recognized as one of the important air quality indicators used to record the
correlation between air pollution and human health. The API information can help government agencies, policy makers
and individuals to prepare precautionary measures in order to eliminate the impact of air pollution episodes. This study
aimed to verify the monthly API trends at three different stations in Malaysia; industrial, residential and sub-urban areas.
The data collected between the year 2000 and 2009 was analyzed based on time series forecasting. Both classical and
modern methods namely seasonal autoregressive integrated moving average (SARIMA) and fuzzy time series (FTS) were
employed. The model developed was scrutinized by means of statistical performance of root mean square error (RMSE).
The results showed a good performance of SARIMA in two urban stations with 16% and 19.6% which was more satisfactory
compared to FTS; however, FTS performed better in suburban station with 25.9% which was more pleasing compared
to SARIMA methods. This result proved that classical method is compatible with the advanced forecasting techniques in
providing better forecasting accuracy. Both classical and modern methods have the ability to investigate and forecast
the API trends in which can be considered as an effective decision-making process in air quality policy.
MeSH terms: Administrative Personnel; Air Pollutants; Air Pollution; Government Agencies; Humans; Industry; Malaysia; Seasons
In recent decades, minimizing the frequency of nutrient deficiency and malnutrition in rural areas of developing
countries becomes an alarming issue. Oyster mushrooms are rich source of both macro and micro nutrients. The
objective of this paper was to evaluate the yield of newly introduced oyster mushroom strains viz. Pleurotus sajorcaju
(PSC), Pleurotus flabellatus (FLB), Pleurotus florida (FLO), Pleurotus ostreatus (PO2
), Pleurotus ostreatus
(HK-51) and Pleurotus geesteranus (PG1
) and to justify their nutritional values when grown in the climatic
condition of Bangladesh. Strain HK-51 produced the highest amount of fresh sporophore (197.80 g). In contrast, the
highest number of fruiting body was obtained from the strain FLO (82 g) followed by strain PSC (69 g). Strain PG1 has
recorded the highest biological yield (278 g), productivity (55%) and biological efficiency (96%). Nutrient and mineral
analysis of sporophore of strain PG1 showed protein (31.80%), lipid (3.6%), potassium (1.3 mg/100 g), phosphorus
(0.8 mg/100 g), calcium (32 mg/100 g), iron (43 mg/100 g), magnesium (12 mg/100 g), copper (3.5 mcg/100 g), zinc
(12.5 mcg/100 g) and manganese (2.3 mcg/100 g). This study showed that the strain PG1
performed well with regard to
quality and productivity as compared to other strains. Hence, oyster mushroom strain PG1
is a potential cheap source
of nutrients and minerals to combat socioeconomic problems including malnutrition, diseases linked to malnutrition,
poverty reduction and agricultural diversity.
The ultimate bearing capacity is an essential requirement in design quantification for shallow foundations especially
for structures built on large rock masses. In many engineering projects, structures built on foundation of heavily jointed
rock masses may face issues such as instability and sudden catastrophic rock slope failure. Determination of the ultimate
bearing capacity (Qult) of foundations resting on rock mass has traditionally been determined by employing several
strength criterions. One of the accepted and widely implemented methods is to use the Hoek-Brown failure criterion 2002,
where the required parameters are determined from a rock mass classification system, Geological Strength Index (GSI).
This paper defines an assessment for ultimate bearing capacity (Qult) based on the Hoek-Brown failure criterion 2002
for a granitic rock slope beneath a 20 m diameter concrete water tank at Bandar Mahkota Cheras, Kajang, Selangor.
Based on the Hoek-Brown failure criterion 2002, the ultimate bearing capacity (Qult) of rock mass was 7.91 MPa. The
actual stress acting on the rock mass was 0.32 MPa. The assessment showed that the rock mass is safe since the ultimate
bearing capacity (Qult) is 24.7 times higher than the actual stress acting on the rock mass.
MeSH terms: Engineering; Foundations; Geology; Silicon Dioxide; Water
The present study was conducted to determine the prevalence and antibiotic resistance of Salmonella sp. isolated from
African catfish (Clarias gariepinus). A total of 30 catfish were harvested from four different farms and four different
wet markets. A total of 60 samples (30 catfish skins and 30 catfish intestines) were used for Salmonella sp. isolation
(pellet-method), its biochemical and serological test. Confirmation of Salmonella sp. were determined by polyvalent
O antisera and polymerase chain reaction (PCR) using genus specific primers for invA genes (DNA amplification
showed one distinct band with molecular weight of 389 bp) and the species of isolated Salmonella sp. were identified
by serotyping. The result showed 6/30 (20%) of fish or 6/60 (10%) of organ samples were positive for Salmonella sp.
Among those positive for Salmonella sp., 4/6 were from intestine samples and 2/6 were from skin samples. No significant
difference was found in the prevalence of Salmonella sp. isolates between fish harvested from farms and wet markets
(p-value= 0.406). The Salmonella serovars identified were Salmonella corvallis (n=3), Salmonella mbandaka (n=2)
and Salmonella typhmurium (n=1). Salmonella sp. isolates were resistance to Penicillin (P 10, 100%), Clindamycin
(DA 2, 100%), Tetracycline (TE 30, 100%) and Rifampicin (RD 5, 100%) and all of the isolates were susceptible or
intermediate resistance to Ceftazidime (CAZ 30) and Trimethopin (W 5). Multiple antibiotic resistance (MAR) index of
all Salmonella sp. isolates in current study was 0.67 indicating that fish sampled in the present study was under high
risk of been exposed to the tested antibiotics.
Rafflesia tuanku-halimii, a new species from Peninsular Malaysia, is herewith described and illustrated. It is related to
R. azlanii and R. sharifah-hapsahiae by coalesced warts on it lobes. Rafflesia tuanku-halimii is different from them in
having window covered by almost united rings and these rings almost wholly covering the window.
Based on the hydraulic fracture width gradually narrows along the fracture length, with consideration of the mutual influences of fracture, non-uniform inflow of fractures segments and variable mass flow in the fracture comprehensively, a spatial separation method and time separation method were used to establish fracture horizontal well’s dynamic coupling model of reservoir seepage and fracture flow. The results showed that the calculation productivity of variable width model is higher than that of the fixed width model, while the difference becomes smaller as time increase. Due to mutual interference of the fractures, the production of outer fracture is higher than that of the inner fracture. When the dimensionless fracture conductivity is 0.1, the middle segment of the fracture dominates the productivity and local peak emerges near the horizontal well. The flow in the fracture is with the ‘double U’ type distribution. As the dimensionless fracture conductivity increase, the fractures productivity mainly through the tips and the flow in the fractures with the ‘U’ type distribution. Using the established fracture width variable productivity prediction model, one can achieve the quantitative optimization of fracture shape.
In incomplete contingency tables, some cells may contain structural zeros. The quasi-independence model, which is a generalization of the independence model, is most commonly model used to analyze incomplete contingency tables. Goodness of fit tests of the quasi-independence model are usually based on Pearson chi square test statistic and likelihood ratio test statistic. In power divergence statistics family, the selection of power divergence parameter is of interest in multivariate discrete data. In this study, a simulation study is conducted to evaluate the performance of the power divergence statistics under quasi independence model for particular power divergence parameters in terms of power values.
MeSH terms: Cell Count; Interior Design and Furnishings; Models, Statistical; Chi-Square Distribution