Multicomposition of Er3+ -Y11-3+ codoped tellurite oxide, Te02-ZnO-PbO-Ti02-Na20 glass has been investigated. A detailed spectroscopic study of the Judd-Ofelt analysis has been performed from the measured absorption spectrum in order to obtain the intensity parameters S2, (t=2, 4, 6). The calculated S2, values were then utilized in the determination of transition probabilities, radiative lifetimes and branching ratios of the Er3+ transitions between the J(upper)-J'(lower) manifolds. Both visible upconversion and near-infrared spectra were characterized under the 980 nm laser diode excitation at room temperature.
CaxZn(1_x)Al204thin films (x = 0.00; 0 .05 ; 0.10; 0.15 and 0.20) were prepared by sol-gel method with the substitution of Zn2+ by Ca" in the framework of ZnAl204. The effect of Ca addition on the structure and morphology of CaZnAl204thin films was investigated by x-ray diffraction (xRD), field-emission scanning electron microscope (FESEM), energy-dispersive x-ray spectroscopy (EDx), ultra-violet visible (uv-Vis) and atomic force microscope (AFM). The xRD patterns showed the characteristic peaks of face-centred cubic (fcc)ZnAl204and CaZnAl204. The addition of Ca increased the crystallite size from 8.9 to 302 nm. The bandgap of CaxZnuld204 thin film was found in the range of 3.40 to 3.84 eV. sEm micrograph shows the morphology of all thin films is sphere-like, with the grain size increased from 33 to 123 nm. The AFM images show the roughness of surface morphology increased. The substitution of Zn2+ by Ca" increased the crystallite size, grain size and surface roughness which evidently increased the density (4.59 to 4.64 glcm3) and dielectric constant (8.48 to 9.54). The composition of CaxZn(1_x)Al204is considered as suitable material for GPS patch antennas.
The physical properties and structural stability of the Quad Flat No-Leads (QFN) package with different gamma radiation doses have been investigated. The packages were irradiated with Co-60 gamma radiation with varying doses of 5 Gy, 50 Gy, 500 Gy, 5 kGy and 50 kGy with operating dose of 2.54 kGylh at room temperature. The infinite focus microscope (IFM) was used to measure the dimensional change and slantinglwarpage behaviour, while the 3D CT Scan X-ray machine was used to determine the occurrence of deflection on a wire in package due to exposure. It is believed that radiation effect on ceramic filler in the epoxy mold compound (EMC) plays an important role to induce the defects and resulted in swelling of the package. The slantinglwarpage behaviour is believed to be caused by the swelling behaviour of ceramic filler and further induced structural stability. The induced stress on the EMC structural after the dimensional change and slantinglwarpage failure leads to the occurrence of wire sweep. The finding suggests that defect production in swelled ceramic filler leads to the occurrence of dimensional and structure instability.
Quantum dots being an interesting class of nanostructures are considered potential prototype systems for novel nano-devices such as single electron transistor (sET). Here in this research, we present an analysis of the electron trajectory in the vicinity of gallium arsenide (GaAs) quantum dot. To perform this study, DFT based methodology is employed to optimize structure of quantum dot and determining the electrostatic potential around the dot. Under the influence of obtained electrostatic potential, trajectory of the moving electron towards the dot is investigated. The results showed that GaAs quantum dot have negative and positive potential surfaces that influence the electron interaction with the dot. These results motivate the development of SET electrode channel where the electron moves towards the dot on the surface with positive potential rather than negative potential surface.
The central theme of nanotechnology to miniaturize devices has stimulated interest in diluted magnetic semiconductors (DMS). DMS that simultaneously exhibit magnetic and semiconducting behavior are capable of parting properties of two different function devices into one. In this research we present our first principles investigations related to the structural and electronic properties of, Cr doped zinc-blende (zB) ZnO, DMS. These calculations are carried out using full potential linearized augmented plane wave plus local orbital (FP-L(APW+lo)) with generalized gradient approximations approach as implemented in WIEN2k code. In this study, the effect of Cr doping on lattice parameters, spin polarized electronic band structure, density of states (Dos) of ZnO is presented and analyzed in detail.
An alternative robust method for testing the equality of central tendency measures was developed by integrating H Statistic with adaptive trimmed mean using hinge estimator, HQ. H Statistic is known for its ability to control Type I error rates and HQ is a robust location estimator. This robust estimator used asymmetric trimming technique, where it trims the tail of the distribution based on the characteristic of that particular distribution. To investigate on the performance (i.e. robustness) of the procedure, some variables were manipulated to create conditions which are known to highlight its strengths and weaknesses. Bootstrap method was used to test the hypothesis. The integration seemed to produce promising robust procedure that is capable of addressing the problem of violations to the assumptions. About 20% trimming is the appropriate amount of trimming for the procedure, where this amount is found to be robust in most conditions. This procedure was also proven to be robust as compared to the parametric (AN0vA) and non parametric (Kruskal-Wallis) methods.
MeSH terms: Polymethacrylic Acids; Prostheses and Implants
The extinction of Br2 molecules in gas state is measured for different wavelengths of incident light in interval of 370 - 570 nm by method of gas spectroscopy. The measurement is made on the basis of Franck-Condon's principle, under which a transition to a more excited state is done without changing the intercore distance (in further text, R). The graph of energy dependence on extinction is drawn. On the graph are recognized two Gausses slopes and their separation (deconvolution) is done. The complete Gausses functions are determined on graph. The method of mirror symmetry is applied on Gausses slopes of extinction and symmetrical extinction values (Es) are obtained. Borders of Franck-Condon's area are determined from ground state of Linear Harmonic Oscillator (LH0). Tables of dependence on R and the excitation energy are given. On the basis of these tables are drawn potential curves of electron energy E(R) in excited electronic states of Br2 molecules as functions of R in Franck-Condon's area.
This paper considers a Monte Carlo simulation based method for estimating cycle stocks (production lot-sizing stocks) in a typical batch production system, where a variety of products is scheduled for production at determined periods of time. Delivery time is defined as the maximum lead time and pre-assembly processing time of the product's raw materials in the method. The product's final assembly cycle and delivery time, which were obtained via the production schedule and supply chain simulation, respectively, were both considered to estimate the demand distribution of product based on total duration. Efficient random variates generators were applied to model the lead time of the supply chain's stages. In order to support the performance reliability of the proposed method, a real case study is conducted and numerically analyzed.
MeSH terms: Income; Monte Carlo Method; Reproducibility of Results
Catanionic system using anionic sodium bis-(2ethylhexyl)sulfosuccinate (Am) and cationic cetyltrimethylammonium bromide (cTAB) is studied. The system is prepared by addition of CTAB solution to a prepared AOT solution until slight anionic-rich catanionic phase is produced. Catanionic system consists of the mixture of different types of surfactants and counterion due to electrostatic interaction between the oppositely charged surfactant. Both of these products affect the in surface activity of the surfactant. Hydrodynamic diameters decrease and clearer solution were seen with the increase of CTAB concentration in solution mixture. As a result, mixed surfactant with larger hydrophobic region and the presence of counterion will induce smaller vesicle to form in catanionic system.
The effect of variation of FeCl2 concentration on the properties of magnetic nanoparticles produced by Massart's procedure was investigated. Samples with different FeCl2 concentration of 0.1, 0.8, 1.0, 12 and 1.5 M were produced. In this technique, an aqueous mixture of ferrous and ferric chloride was co precipitated under controlled conditions to yield magnetic iron oxide nanoparticles. Thermogravimatric analysis (up to 700°C) showed a continuous weight loss from room temperature to 200°C that was mainly due to evaporation of water from the sample. Above 230°C, no more weight loss was observed indicating the stability of the maghemite nanoparticles. The lattice parameter of the samples obtained from X-ray diffraction analysis showed that the nanoparticles formed were maghemite (y-Fe 20 ). The crystallite sizes calculated from the broadening of xRD peaks were 6.79, 6.56, 6.15 , 6.72 and 7.24 nm for FeCl2 concentration of 0.1 , 0.8, 1.0, 1.2 and 1.5 M, respectively. The magnetization curves showed no hysteresis indicating that the particles were superparamagnetic. The least upper bound of the 'magnetic' sizes calculated were 7.53, 629, 5.92, 6.41 and 8.04 nm and the physical sizes measured from TEM images were 5.97, 6.02, 4.98, 535 and 5.98 nm, respectively. The crystallite, magnetic and physical sizes were similar, indicating that the particles are monocrystals.
In this study, graphene oxide (Go) filled epoxy nanocomposites were prepared using hot pressed method. The GO was produced using modified Hummers' method. The produced GO at different compositions (0.1, 0.3 and 0.5 wt%) were mixed with epoxy before the addition of hardener using ultra-sonication. The produced epoxy nanocomposites were characterized in terms of mechanical and thermal properties. The mechanical properties of the nanocomposites were significantly enhanced by the addition of GO. About 50% of increment in the flexural strength of the composite sample filled with 03 wt% of GO as compared to the neat epoxy sample. However, only slight improvement in the impact strength of the composite were obtained by adding 0.1 wt% of GO.
Penggunaan proses pengendapan elektroforetik (EPD) telah menunjukkan potensi yang memberangsangkan dalam pembangunan komponen katod untuk sel tunggal sel fuel oksida pepejal (soFc). Sehubungan itu, kesan saiz elektrod lawan dan masa pengendapan terhadap ketebalan dan kualiti filem komposit katod LSCF-SDC karbonat pada substrat seria terdop samarium (sDc) karbonat telah dikaji untuk membuktikan kebolehlaksanaan kaedah ini. Kesan perubahan parameter tersebut terhadap penghasilan filem LSCF-SDC karbonat dikenal pasti dengan menetapkan nilai pH ampaian dan voltan kenaan. Parameter masa pengendapan diubah suai dengan lima masa yang berbeza iaitu antara 10 - 30 min, manakala dua saiz elektrod lawan yang digunakan ialah 25 x 25 mm2 dan 50 x 50 mm2. Filem komposit katod kemudian disinter pada suhu 600°C selama 90 min. Pencirian mikrostruktur dan ketebalan filem LSCF ini diperoleh menggunakan mikroskop imbasan elektron (sEm). Penggunaan saiz elektrod lawan yang besar (50 x 50 mm2) didapati mampu menghasilkan filem komposit katod yang lebih tebal . Selain itu, kesan perubahan parameter (masa pengendapan dan saiz faring elektrod lawan) dikenal pasti melalui analisis berat dan ketebalan filem LSCF-SDC karbonat. Filem katod berketebalan 4.6 - 30.8 ,um telah berjaya diendap pada tempoh pengendapan yang digunakan. Ketebalan katod komposit LSCF-SDC karbonat yang diperoleh berada dalam julat ketebalan yang telah dihasilkan oleh pengkaji terdahulu melalui kaedah pembentukan yang sama ke atas bahan katod lain. Keputusan kajian menunjukkan bahawa kaedah pengendapan elektroforetik bagi pembentukan katod komposit amat berpotensi untuk kajian yang lebih intensif.
The electrical characteristics of a filamentary dielectric barrier discharge (DBD) are studied experimentally and numerically. The DBD system which has parallel plate electrodes geometry is powered by a 50 Hz power supply and operated at atmospheric air. A dynamic electric circuit model considering the discharge region and the non-discharge region being connected by a surface resistance is proposed. Simulation using this model is shown to fit the experimentally measured QV diagram satisfactorily. The effects of the air gap distance and the dielectric surface on the discharge behavior are then investigated. It is found that the surface resistivity of the dielectric is one of the important parameters governing the discharge behavior.
MeSH terms: Electricity; Electrodes; Government; Electric Power Supplies
Analisis terma dan prestasi modul fotovoltan semi-lutsinar yang dipasang pada tetingkap dwi kaca (TDK) telah dikaji. Di dalam TDK terjadi pemindahan haba olakan yang disebabkan oleh perbezaan suhu. Perisian COMSOL digunakan untuk menyelesaikan model matematik dengan empat jenis gas yang berlainan disimulasikan untuk mengisi ruang dalam TDK iaitu udara, argon, kripton dan xenon. Ruang dalam TDK diubah antara 5 hingga 100 mm. Keadaan cuaca di Kuala Lumpur, Malaysia telah digunakan. Modul fotovoltan yang digunakan untuk kajian simulasi ialah jenis silikon amorfus (Si-a). Kajian ini mendapati penggunaan gas xenon dalam ruang TDK memberikan prestasi maksimum dalam mengurangkan beban penyejukan. Ketebalan optimum ruang TDK bergantung kepada jenis gas yang digunakan dan secara umumnya berada dalam julat 10 hingga 20 mm.
There are very few prognostic studies that combine both clinicopathologic and genomic data. Most of the studies use only clinicopathologic factors without taking into consideration the tumour biology and molecular information, while some studies use genomic markers or microarray information only without the clinicopathologic parameters. Thus, these studies may not be able to prognoses a patient effectively. Previous studies have shown that prognosis results are more accurate when using both clinicopathologic and genomic data. The objectives of this research were to apply hybrid artificial intelligent techniques in the prognosis of oral cancer based on the correlation of clinicopathologic and genomic markers and to prove that the prognosis is better with both markers. The proposed hybrid model consisting of two stages, where stage one with ReliefF-GA feature selection method to find an optimal feature of subset and stage two with ANFIS classification to classify either the patients alive or dead after certain years of diagnosis. The proposed prognostic model was experimented on two groups of oral cancer dataset collected locally here in Malaysia, Group 1 with clinicopathologic markers only and Group 2 with both clinicopathologic and genomic markers. The results proved that the proposed model with optimum features selected is more accurate with the use of both clinicopathologic and genomic markers and outperformed the other methods of artificial neural network, support vector machine and logistic regression. This prognostic model is feasible to aid the clinicians in the decision support stage and to identify the high risk markers to better predict the survival rate for each oral cancer patient.
Fermentation of legumes is a well-recognised preserving method that not only diversifies the sensory attributes of the legume-based foods but also enhances its nutritional value. This study aimed to evaluate the changes in amino acids content of soybean, garbanzo bean and groundnut upon pre-treatments (soaking and steaming) and fermentation times ( 18, 24 and 30 h). The amino acids analysis was performed with a HPLC system using AccQTag method. The results obtained showed that raw soybean contain the highest amount of essential and non-essential amino acids followed by raw garbanzo bean and groundnut. After the soaking process, the amount of amino acids obtained was significantly increased in all three legumes. However, the steaming process was found to cause significant decrease in the amino acids content. After the steaming process, the legumes were inoculated with Rhizopus oligosporus and incubated at 30°C and 65% RH. At 18 h of fermentation time, the amount of total amino acids were found to increase by 26% in fermented groundnut and 16% in both soybean and garbanzo bean compared to after steaming. Further fermentation time of 24 h shows further enhancement in the amino acids content in all three legumes. Groundnut shows the highest increased of 71% in total amino acids content followed by 63% increased in garbanzo bean and 53% increase in soybean. However, prolong fermentation time of 30 h shows a decrease in total amino acids content in all three legumes which indicates the slow process of mould degradation have occurred. Therefore, fermented legumes must be consumed at the appropriate time of fermentation in order to get the benefit from the highest accumulation of amino acids content.
This study was carried out to know the bacteria population density in the blood cockle (Anadara granosa) and green lipped mussel (Perna viridis), to analyse the bacteria resistance towards antibiotics and antimicrobial activity of isolates against selected pathogen. Samples of blood cockle and green lipped mussel were obtained from five areas in Kedah and Negeri Sembilan. Bacterial population densities in mussels and cockles were 3 x 102 - 8 x 108 cFulmL and 5 x 102 - 5 x 108 cFulmL, respectively. A total of 162 isolates were obtained, of which 131 isolates were from mussels and 31 isolates were from cockles. Vibrio sp. was the most dominant genus in both types of samples. Antibiotic testing of all isolates showed most were resistant to Penicillin (10 U) and most were sensitive to Ciprofloxacin (5 Jig). Most isolates (160/162) showed resistance to at least two antibiotics and 10 isolates were resistant to more than five antibiotics. Multiple antibiotic resistance indices (MAR) were calculated based on the antibiotic resistance results. Most isolates had a MAR index value of 02 which indicated the isolates were not contaminated with antibiotic residues. The highest index value was 0 .7 . Fifteen out of 39 isolates which produced beta-lactamase enzyme were tested for antimicrobial activity against selected pathogen. Results indicated that antimicrobial activity were varies among the isolates. Isolate smii-Ip produced antimicrobial activity against six out of the nine tested pathogen and none of the isolates active against Pseudomonas mirabilis.
The study was aimed to analyze the physicochemical properties and antioxidant activities in five batches of seeds and oils of Nigella sativa, obtained from Malaysia, Iran and Yemen. Proximate analysis showed that the seeds contained 20.63-28.71% crude fat, 11.35-14.04% crude protein, 5 .37-7 .93% total moisture, 4.15-4.51% total ash contents and 48.69-57.18% total carbohydrate contents. Physicochemical analysis showed a refractive index of 1.4697-1.4730, specific gravity of 1.369-1376 g/cm3, peroxide value of 3.33-21.33 meq 02/kg, 184-220 mg/g in saponification number and unsaponifiable matter of 1.1-1.8% in the oil samples. The seeds showed high mineral content such as Ca (2242 mg/kg), K (6393 mg/kg) and Mg (2234 mg/kg). The oil sample from Kelantan, Malaysia contained the lowest saturated fatty acid (sFA) (1.42±029%) while Sudan, Yemen contained the highest content of polyunsaturated fatty acid (PUFA) (65 .13 ±5 .45%). Monounsaturated fatty acid (MUFA) were found the highest (20 .45 ±2 .61%) in the seed samples originated from Iran. Seeds from Iran showed the highest antioxidant activity (IC50 = 1.49 mg/mL) and total phenolic content (30.84 mg GAE/g) while oil sample from Sudan, Yemen has the highest antioxidant activity (IC50 = 4.48 mg/mL). Seeds from Iran have the highest quality among the seed samples while oil samples from Kelantan, Malaysia was the best among the oil samples in terms of low SFA, high PUFA, MUFA and antioxidant activities.
The selected trace metals in the soft tissue of Thais clavigera from 11 sampling sites along the coastal waters of the east coast of Peninsular Malaysia were studied. Significant inter-spatial variations in trace metals were recorded. Sites with relatively high concentrations of the contaminant metals Hg, Cd, Pb and Zn are correlated to their close proximity to industrial and urban sites or to boating and aquaculture activities. This could possibly be contributed by the high growth of industrial activities like port and sewage release. Interspatial comparison with previous studies indicated lower measurement. Meanwhile, comparison with other studies around the world also designated lower values except for Zn. The metal accumulation patterns indicated an enrichment of essential metals over non-essential metals. Comparison of metal concentration with maximum permissible limits of toxic metals in food established in different countries, as well as Malaysian Food Act 1983 and Food Regulations 1985 Fourteen Schedule, indicated the values were well within safety levels.
This study aimed to measure and compares the concentration of metals accumulated in various parts (grains, stems and roots) of paddy (Oryza sativa). Thirty samples were collected from selected paddy field in Alor Setar, Kedah, Malaysia. Metals (mils ,9Be,1141'a7,59Co,52Cr and 208Pb) concentration in various parts of the paddy and soil were analysed by using the sensitive Inductively Coupled Plasma-Mass Spectrometry (icP-Ms). Bioconcentration factor (BCF) and translocation ratio were calculated based on the concentration of metals obtained. The mean concentration (mg/kg) of metals in grain samples were 0 .06±0 .12 for mils , 0 .0038±0 .0037 for9Be , 0 .01±0 .01 for 114Cd, 0.14±0.19 for "Co and 0 2 1±0 .15 for 208Pb while 52Cr concentration in all samples were below the ICP-MS detection limit. From the calculated translocation ratio, absorption of paddy had relation: root > stem >> grain. This study showed that measured concentration of metals in grain samples were all below the maximum permitted proportion (mg/kg) of Fourteenth Schedule (Regulation 38) of the Malaysian Food Regulation 1985.