An archeological study, conducted by the Archaeological Global Research Centre, Universiti Sains Malaysia shows the evidence of shock metamorphisms (suevite breccia) and crater morphology at Bukit Bunuh in Lenggong area of north Perak, Malaysia. A regional gravity survey focusing at Bukit Bunuh and its surrounding area was conducted to justify the occurrence and to determine the diameter and subsurface geological structure of the Bukit Bunuh impact crater. The gravity survey, using a Scintrex CG5 gravity meter, comprises 476 gravity stations with a 500 m spacing covering an area of approximately 160 km2. The elevation of the gravity stations were obtained by using a pair of Wellace and Tiernan altimeters. The gravity data were corrected for drift, free air, bouguer, latitude and terrain in order to produce a corrected gravity data of the study area. The data were processed and analysed using Oasis Montaj (Geosoft software) to produce bouguer, residual, Total Horizontal Derivative (THD) residual, regional and Total Horizontal Derivative (THD) regional anomaly maps for qualitative and quantitative interpretations. The bouguer gravity map shows relatively low negative anomaly with nearly circular shaped contour around the Bukit Bunuh area. This anomaly was interpreted as the remnant of meteorite impact structure with rounded shaped crater in the study area. The bouguer anomaly map shows that the Bukit Bunuh impact crater has a diameter of approximately 2.5 km. The impact structure was successfully modeled as a complex impact crater with maximum depth of about 300 m. The bouguer anomaly map also showed the possible occurences of at least two more impact craters located in the northeast and southeast areas of the Bukit Bunuh crater and these structures need further investigation for confirmation.
Magnetic surveys were carried out in Farigh area which is located in the eastern part of the Libyan Sirte basin. Interpretation of the onshore magnetic anomaly of this area, suggests that the high total magnetization may be caused by an intrusive body. Analysis of the magnetic power spectra indicates the presence of four sub-anomalies at depths of 340 m, 1400 m, and 2525 m which is probably related to the igneous rocks. The presence of igneous rock as basement at depth of 4740 m was confirmed by drilling. Assuming that all rock magnetization in the area is caused by induction in the present geomagnetic field, it strongly suggests that the causative structure has a remnant magnetization of declination (D) = −16° and inclination (I) = 23°. Based on pseudogravity data, the total horizontal derivative map shows high gradient values in NW-SW trends related to the structures in the eastern part of the Sirte basin. The 3D Euler deconvolution map derived from gravity data clearly indicates the location of igneous body in the study area as well as its tectonic trends and depth, which is estimated at 350 m to 1400 m below the surface. Depth of gravity anomalies at 1400 m to 2525 m is considered as anomalies in between shallow and deep. Anomaly at depth of approximately 4740 m below the surface is interpreted as basement rock. Geologically, the magnetic survey shows that the source of anomaly is a mafic igneous rock of Early Cretaceous age. The study also discovered a left-lateral sheared fault zone along the NW-SE of Hercynian age which was believed to be reactivated during Early Cretaceous.
The aim of researchers when comparing two independent groups is to collect large normally distributed samples unless they lack the resources to access them. In these situations, there are a myriad of non-parametric tests to select, of which the Mann Whitney U test is the most commonly used. In spite of its great advantages of usage, the U test is capable of producing inflated Type I error when applied in situation of heterogeneity or distinct variances. This current study will present a viable alternative called the refined Mann-Whitney test (RMW). A Monte Carlo evaluation test is conducted on RMW using artificial data of various combinations of extreme test conditions. This study reviews that the RMW test justified its development by enhancing the performance of the U test. The RMW test is able to control well its Type I error rates even though it has a lower power.
The deficiency in the human auditory system of individuals suffering from sensorineural hearing loss (SNHL) is known to be associated with the difficulty in detecting of various speech phonological features that are frequently related to speech perception. This study investigated the effects of speech articulation features on the amplitude and latency of cortical auditory evoked potential (CAEP) components. The speech articulation features included the placing contrast and voicing contrast. 12 Malay subjects with normal hearing and 12 Malay subjects with SNHL were recruited for the study. The CAEPs response recorded at higher amplitude with longer latency when stimulated by voicing contrast cues compared to that of the placing contrast. Subjects with SNHL elicited greater amplitude with prolonged latencies in the majority of the CAEP components in both speech stimuli. The existence of different frequency spectral and time-varying acoustic cues of the speech stimuli was reflected by the CAEPs response strength and timing. We anticipate that the CAEPs responses could equip audiologist and clinicians with useful knowledge, concerning the potential deprivation experience by hearing impaired individuals, in auditory passive perception. This would help to determine what type of speech stimuli that might be useful in measuring speech perception abilities, especially in Malay Malaysian ethic group, for choosing a better rehabilitation program, since no such study conducted for evaluating speech perception among Malaysian clinical population.
Nanozarah Co-Ni-Cu telah disediakan dengan kaedah elektropengendapan pada keupayaan pengendapan -925 mV (SCE) menggunakan larutan sulfat (0.018M Co2++ 0.180M Ni2+ + 0.002M Cu2+) yang mengandungi surfaktan Glukopon 215 CSUP dan juga tanpa surfaktan. Kesan kepekatan surfaktan terhadap saiz dan sifat magnet nanozarah Co-Ni-Cu yang terhasil telah dikaji. Analisis morfologi permukaan endapan yang diperoleh dilakukan dengan menggunakan mikroskop elektron imbasan pancaran medan (FESEM) manakala sifat magnetnya diselidiki dengan menggunakan magnetometer getaran sampel (VSM). Nanozarah Co-Ni-Cu yang disediakan daripada larutan yang mengandungi Glukopon 215 CSUP didapati berbentuk sfera dengan saiz berskala nanometer. Saiz zarah paling kecil ialah lebih kurang 50 nm, diperoleh pada kepekatan surfaktan 5 %v, iaitu kepekatan paling tinggi yang dikaji dalam kajian ini. Kepaksaan (Hc) didapati lebih tinggi pada sampel yang disediakan daripada elektrolit yang mengandungi surfaktan berbanding tanpa surfaktan.
A single wall single image x-ray radiographic technique was adopted to investigate thickness variation of steel specimens caused by uniform corrosion. The ability of the 100 kV-160 kV x-rays to produce a meaningful film density for steel was also investigated. The thickness contour maps of corroded steel plates were found matching with the x-ray film density contour maps of the plates. The results confirm that x-ray radiography can be used to detect the thickness reduction of steel caused by uniform corrosion.
Bagi mengesan perubahan ketebalan keluli akibat kakisan seragam maka radiografi sinar-x teknik imej tunggal dinding tunggal telah digunakan. Kemampuan sinar-x 100 kV-160 kV menghasilkan ketumpatan filem yang sesuai untuk keluli telah juga dikaji. Peta kontur ketebalan bagi spesimen kepingan keluli yang telah mengalami kakisan seragam didapati sepadan dengan peta kontur ketumpatan filem radiografi sinar-x bagi spesimen tersebut. Kajian ini menunjukkan radiografi sinar-x boleh digunakan bagi mengesan penipisan keluli akibat kakisan seragam.
Kajian telah dijalankan ke atas kualiti bebola ayam dengan penambahan ekstrak daun selom (Oenanthe javanica) dan mengkudu (Morinda citrifolia) serta lemak sawit merah (Carotino®). Selom dan mengkudu telah ditentukan kandungan polifenol jumlah (TPC), kuasa penurunan ferum dan aktiviti antioksida masing-masing. Kaedah pengekstrakan air menunjukkan hasil yang baik dan stabil berbanding pengekstrakan metanol dan diaplikasikan ke dalam pemprosesan bebola ayam. Terdapat 5 pelakuan bebola ayam iaitu bebola ayam kawalan (C), bebola ayam ditambah ekstrak selom (T1), bebola ayam ditambah ekstrak selom dan lemak Carotino® (T2), bebola ayam ditambah ekstrak mengkudu (T3) dan berbola ayam ditambah lemak Carotino® (T4). Bebola ayam telah disimpan pada suhu 4°C selama 12 hari. Analisis dilakukan selang 4 hari untuk memerhatikan perubahan nilai asid tiobarbiturik (TBA) dan nilai peroksida (PV) pada bebola ayam. Didapati sampel T4 memberikan nilai keseluruhan TBA paling rendah diikuti dengan sampel T2, sampel T1, sampel kawalan (C) dan sampel T3. Manakala sampel T2 memberikan nilai peroksida keseluruhan paling rendah diikuti dengan sampel T4, sampel T1, sampel kawalan (C) dan akhir sekali sampel T3. Keberkesanan antioksidan menurun daripada: T2 > T4 > T1 > C > T3. Didapati ekstrak selom dan lemak Carotino® mampu bertindak sebagai antioksidan dalam merencatkan pengoksidaan lipid di dalam bebola ayam.
Atomic force microscopy (AFM) has a wide range of applications and is rapidly growing in research and development. This powerful technique has been used to visualize surfaces both in liquid or gas media. It has been considered as an effective tool to investigate the surface structure for its ability to generate high-resolution 3D images at a subnanometer range without sample pretreatment. In this paper, the use of AFM to characterize the membrane roughness is presented for commercial and self-prepared membranes for specific applications. Surface roughness has been regarded as one of the most important surface properties, and has significant effect in membrane permeability and fouling behaviour. Several scan areas were used to compare surface roughness for different membrane samples. Characterization of the surfaces was achieved by measuring the average roughness (Ra) and root mean square roughness (Rrms) of the membrane. AFM image shows that the membrane surface was composed entirely of peaks and valleys. Surface roughness is substantially greater for commercial available hydrophobic membranes, in contrast to self-prepared membranes. This study also shows that foulants deposited on membrane surface would increase the membrane roughness.
Membrane fouling caused by the adsorption of fatty acids limits the application of membrane technology in oleochemical industry especially for the pretreatment of glycerin-rich solution. The aim of the work presented in this paper was to understand the adsorptive fouling of palm oil based fatty acid on ultrafiltration membranes. The influence of solution pH, molecular weight cut-off (MWCO) and hydrophobicity of the membrane were studied. Oleic acid was used as a foulant, representing the long chain palm oil based fatty acid in glycerol−water solution. The outer membrane exposed to the mixtures for 6 h without pressure. The stirring speed was set at 300 rpm and polyethersulfone (PES) membranes with MWCO of 5, 20 and 25 kDa were used. The adsorptive fouling was determined using the relative flux reduction (RFR) method. It is demonstrated in this study that PES membranes are susceptible to the deposition of fatty acids on the membrane surface and pores. The fouling phenomenon at low pH is more severe than that of high pH due to the attractive force between solutes and the membrane. The PES membranes after adsorption were characterized by contact angle and Fourier transform infrared (FTIR), while the surface was visualized with scanning electron microscopy (SEM).
Palm oil mill effluent (POME) treatment has developed in the last decade. Due to the characteristic and volume of POME,
it needed a complete treatment to reduce the pollutant content. Three pre-treatments method, ultrafiltration, adsorption
and decantation were applied prior to nanofiltration (NF) membrane. The polyethersulphone membrane, montmorillonite
as the adsorbent and modern decanter was investigated in this research. Two types of NF membrane, named NF-1 and
NF-ASP30 were used after pre-treatment. The removal of four important parameters were determined i.e. COD, TSS, colour
and turbidity. The results showed that the adsorption and UF is better than decantation pre-treatment. The ultrafiltration
and adsorption can reduce POME content more than 80% for all parameter while decantation varied between 40 and 80%.
The combination of ultrafiltration and adsorption with both of NF membrane can removed almost all the parameter. But
the decantation can only remove the turbidity but not for the rest of the parameters. Besides the POME content, the flux
decline for both of NF membrane was also investigated. The flux of NF-1 membrane was higher than NF-ASP30 membrane
but NF-ASP was more relative stable for the flux decline. Overall, NF-1 has better performance in flux decline.
In this paper, systems of second-order boundary value problems (BVPs) are considered. The applicability of the homotopy-perturbation method (HPM) was extended to obtain exact solutions of the BVPs directly.
A nitrate-based nickel salt was used to prepare NiO-BaCe0.54Zr0.36Y0.1O2.95 (NiO-BCZY) composite powders by an evaporation
and decomposition of solution and suspension (EDSS) method. The prepared powders with different weight ratios of NiO to
BCZY (NiO:BCZY) were denoted as S1 (50:50) and S2 (60:40). The powders were characterized using Thermogravimertic
analyzer (TGA), X-ray diffractometer (XRD) and scanning electron microscope (SEM) equipped with energy dispersive
X-ray (EDX) spectrometer. TGA results showed that the thermal decomposition of intermediate compounds in the dried
powder (T = 150°C) completed at ~700°C. XRD analysis confirmed that the calcined powder (T = 1100°C) of S1 and
S2 did not show any crystalline peaks related to BCZY compound as the peaks associated to impurity phases of BaCeO3
and BaZrO3
were appeared in their XRD patterns. The impurity phases along with NiO still remained in the S1 sample
after it was calcined at 1400°C. As the calcination temperature increased, the particles size of S1 also increased and Zr
elemental composition deviates from the nominal stoichiometric of the NiO-BCZY as proven by SEM/EDX analysis. The
results indicate that the formation of homogenize NiO-BCZY composite prepared using EDSS method was not favored even
after calcined at high temperature (T = 1400°C).
The aim of the study was to determine the frequency, size and location of apical and lateral foramina on anterior teeth. A total of 100 anterior teeth consisting of maxillary and mandibular incisors and canines were fixed in 10% formalin. Periodontal tissue remnants were mechanically removed and teeth were stained in 2% aqueous silver nitrate. The teeth were dried and examined using a Leica MZ 7.5 zoom stereomicroscope. The size of apical and lateral foramina and their distance from the anatomical apex of the tooth were measured directly using a calibrated eyepiece scale. Accessory foramina more than 1.8 mm from the apex were regarded as lateral foramina. Eighteen percent of teeth possessed more than one apical foramen. Seven teeth (three maxillary centrals, three maxillary canines, one mandibular lateral) had 11 lateral foramina each. The mean diameter of the lateral foramina was 0.14 mm (SD = 0.08) and their mean distance from the apex was 4.49 mm (SD = 2.63, range 1.9-10.5 mm). Multiple foramina were most common on maxillary canines and least common on maxillary laterals. The mean diameter of apical foramina for all teeth possessing a single foramen was 0.35 mm (SD = 0.10) and the mean apical foramen diameter for all teeth with multiple apical foramina was 0.22 mm (SD = 0.08). Most anterior teeth possess one apical foramen and no lateral foramina; about 20% possessed more than one apical foramen and about 10% possessed one or more lateral foramina. These findings should be considered when root-treating anterior teeth.
In this paper, we examined a model of cell invasion focusing on the wavefront of the neural crest (NC) cells in the case of Hirschsprung’s disease (HSCR). Hirschsprung’s disease (HSCR) is a congenital defect of intestinal ganglion cells and causes patients to have disorders in peristalsis. This simulation model was performed using the fractional differential equations (FDEs) based upon two basic cell functions. Here, we simulated the mathematical model in a one-dimensional setting, based on the fractional trapezoidal numerical scheme and the results showed an interesting outcome for the mobility of the cellular processes under crowded environments.
Sn doped zinc oxide polycrystalline thin films were prepared by sol-gel process. The sol was prepared from zinc acetate dehydrate and tin chloride were used. 2-methoxyethanol and monoethanolamine were used as the solvent and stabilizer, respectively. The quantity of tin in the sol was 0, 15, and 25 at.% Sn with annealing temperature 400, 500 and 600°C. Structural investigation including surface morphology and microstructure was carried out by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The films give a hexagonal wurtzite structure with diffraction peaks at (100), (002) and (101). Changes in particle size with an increase in annealing temperature were observed in the SEM micrograph. The optical properties were determined by photoluminescence (PL) and UV-Visible (UV-VIS-NIR) spectrometer. The band gaps increased (2.78 eV to 4.10 eV) as the concentration of Sn was increased and the increasing of annealing temperature. Annealing temperature plays a key role in the formation of defects which is strongly related to the nonradiative recombination centers. The increment of the band gap is acceptable as a requirement for good anti-reflecting coating element. Therefore, these films can be applied on silicon solar cells.
Polycrystalline samples of (Pr1-xNdx)0.67Ba0.33MnO3 with x = 0.0, 0.167, 0.33, 0.5, 0.67, 0.833, and 1.0 have been prepared using the solid state reaction. The samples were calcined at 900oC for 12 hours, pelletized and sintered at 1300oC for 24 hours. The structures were investigated via X-ray diffraction (XRD) method. XRD patterns showed orthorhombic distorted perovskite structures. The scanning electron microscopy (SEM) micrographs showed the disorder of the structure in all substitutions. This influenced the value of the magnetoresistance (MR). The MR effects are measured using the four point probe technique with a magnetic field of B ≤ 1T at temperatures of 90, 100, 150, 200, 250, 270 and 300 K. Overall, the MR increased as the temperature decreased. All doping concentrations gave a small variation range (~10% to ~56%). The highest MR value of 56.5 % is observed at 100 K for a sample with x = 1.0. The influence of disorder on the magnetoresistance in (Pr1-xNdx)0.67Ba0.33MnO3 manganites at low temperatures was also discussed in this paper.
Nutritive value and persistence of different alfalfa cultivars, but very little information is available in the literature on
mineral concentrations, especially on microelements. This study was carried out to determine crude protein and mineral
contents in alfalfa cultivars from two different locations, Ankara and Konya provinces, in Central Anatolia during 2005
and 2007. The experiment was conducted using a randomized complete block design with three replications. Significant
differences in many investigated traits were found between cultivars, years, locations and location x year, location x
cultivar, year x cultivar, and location x year x cultivar interactions. A crude protein ratio and micro and macro element
contents (K, P, Mg, Ca, Mn, Fe, Zn, B, Mo, Cu, Cr, Se and Al) were analyzed in alfalfa on a dry weight basis. The results
showed that the protein content ranged 17.23 to 20.71%. The macro element contents ranged 2.06 to 3.95 g kg–1 for
K, 13.65 to 23.25 g kg–1 for P, 1.31 to 2.53 g kg–1 for Mg, 6.71 to 22.81 g kg–1 for Ca, and 44.3 to 92.7 mg kg–1 for Fe,
whereas the microelement contents ranged 15.4 to 54.3 mg kg–1 for Mn, 24.6 to 121.9 mg kg–1 for Zn, 46.4 to 85.4 mg
kg–1 for B, 0.50 to 6.13 mg kg–1 for Mo, 3.13 to 4.17 mg kg–1 for Cu, 0.93 to 2.40 mg kg–1 for Cr, 0.77 to 1.03 mg kg–1
for Se and 31.2 to 57.8 mg kg–1 for Al. Significant differences at the p<0.01 or p<0.05 level in many investigated traits
were found between cultivars, years, locations and location × year, location × cultivar, year × cultivar, and location
× year × cultivar interactions. In conclusion, due to the fact that the location × year × cultivar interaction was found
statistically significant, we suggest that appropriate cultivars are selected for each region.
A suitable and cost-effective microfabrication technique for processing aluminum micropart is required, as the choice
of aluminum microparts for aerospace, electronics and automobile components is preferred over other metals due to its
excellent properties. Meanwhile, powder injection molding (PIM) is identified as an economical manufacturing technique
for processing ceramic and micro-metal powders into microparts and or components. Therefore, this study investigates
formulation and processing of aluminum PIM feedstock using a custom-made machine. The investigation is focused on
the effect of mixing process parameters (powder loading, rotor speed and mixing temperature) and the suitability of
the backbone polymer. The formulated PIM feedstock constituents are paraffin wax (PW), stearic acid (SA), high-density
polyethylene (HDPE)/ medium-density polyethylene (MDPE) alternatively and aluminum micro-metal powder. Taguchi
method is used for the design of experiments (DOEs) and analysis. In addition, response surface methodology (RSM) is
employed to develop empirical viscosity models. The optimum powder-binder mixing ratio of 58:42 vol. % with rotor
speed of 43 rpm were determined for preparing aluminum PIM feedstock using mini-lab mixer developed. The empirical
model developed for aluminum PIM feedstock viscosity shows a good fit with R2
values of 0.84 using HDPE and 0.96 for
MDPE binder system. This investigation demonstrates preparation and suitability of aluminum PIM feedstock using waxbased
binder system.
In this study, group acceptance sampling plan (GASP) proposed by Aslam et al. (2011) is redesigned where the lifetime of
test items are following Pareto distribution of 2nd kind. The optimal plan parameters are found by considering various
pre-determined designed parameters. The plan parameters were obtained using the optimization solution and it also
concludes that the proposed plan is more efficient than the existing plan as it requires minimum sample size.
Corrosion is one of the major problems in petroleum mining and processing industry. The pipelines used to transport crude oil from reservoir to the processing installation were made from carbon steel that is susceptible towards corrosion. One of the best methods to prevent corrosion that occurred at the inner parts of carbon steel pipelines is to use organic corrosion inhibitor. One of the potent organic corrosion inhibitors is amino acids derivatives. In this study, dipeptide compound namely benzoylalanylglycine methyl ester and benzoylalanylglycine have been synthesized. The structure elucidation of the products was performed by IR, MS and NMR spectroscopy. The determination of corrosion inhibition activity utilized the Tafel method. The corrosion inhibition efficiency of glycine methyl ester, benzoylalanine, dipeptide benzoylalanylglycine methyl ester and dipeptide benzoylalanylglycine were 63.34%, 35.86%, 68.40% and 27.72%, respectively. These results showed that the formation of dipeptide benzoylalanylglycine methyl ester, derived from carboxylic protected glycine and amine protected alanine, increased the corrosion inhibition activity due to the loss of acidity center in the structure of glicine and L-alanine that would induce the corrosive environment towards carbon steel.