Journal of Mathematical and Fundamental Sciences
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Phase Transformation of Rice Husk Ash in the Synthesis of ZSM-5 without Organic Template
Get PDFPhase transformation of rice husk ash in the synthesis of ZSM-5 without organic template at various crystallization times has been studied. Zeolite has been synthesized using the hydrothermal method at 175 °C with molar ratio 10Na2O : 100SiO2 : 2Al2O3 : 1800H2O with addition of silicalite-1 as seed. Solids were characterized using X-ray diffraction (XRD), infrared (IR) spectroscopy and scanning electron microscopy (SEM) techniques. Analysis of the results of XRD and IR spectroscopy indicated that ZSM-5 crystalstarted to form at 12 h of crystallization time, reaching high crystallinity after 24 h. With a crystallization time of more than 48 h, the ZSM-5 crystals had completely transformed into more stable quartz phase. Results indicated that phase transformation has occurred, in which an amorphous phase of rice husk ash has been transformed to ZSM-5 crystal phase during the early crystallization stage and continued to transform to disordered α-cristobalite phase and lastly quartz phases. SEM showed that the morphology of the ZSM-5 crystal was of an irregular hexagonal shape with particle size distribution around 3-7 μm
On The Double-Vacua Duality of Multi-Scalar Higgs and NGB-Dual Higgses in Scherk-Schwarz Breaking of 5-dimensional SU(6) Symmetry
Get PDFA special condition of Scherk-Schwarz and S^1/Z2 orbifold breaking brings about both a weakly-coupled SU(6) baby Higgs and a strongly-coupled will-be simplest little Higgs scalar in the near-brane of SU(3) x SU(3)x U(1). The latter produces SU(3) VEVs and simplest little-like Higgs after triplet-triplet splitting and, under quadratic-based and non-quadratic-based Coleman-Weinberg potential, the simplest little-like Higgs yields exotic Higgses, scalar-pair and 3-scalar Higgses in the so-called one-by-one and collective breakings. A generalized non-quadratic-based Coleman-Weinberg potential utilizing a NGB-like scalar produces NGB-dual Higgses with a squared mass relevant to the components of a 3-scalar Higgs that further create a duality of 3-scalar Higgs and NGB-dual Higgses. This is due to a double-vacua property such that each vacuum responds equally to the shifts happening at either non-zero or zero-VEV vacuum
Effect of Furnish on Temperature and Vapor Pressure Behavior in the Center of Mat Panels during Hot Pressing
Get PDFParticleboard achieves its overall performance characteristics during hot pressing process. As this process is influenced by several factors, particularly temperature and pressure, it is very important to understand the behavior of both. This study investigates the effects of furnish materials on temperature and vapor pressure behavior inside particleboard mat panels during hot pressing. Strand type particles from hinoki and ring-flaker recycled wood particles were used as furnish for laboratory-scale particleboard panels with a target density of 0.76 g/cm³. Mat panels with a moisture content of about 10% were hot pressed at a platen temperature of 180°C and an initial pressure of 3 MPa until the mat center reached the same temperature as the platen. A press monitoring device (PressMAN Lite) was used for detecting the temperature and vapor pressure change in the center of the mat panels. The study showed that the furnish type affected the temperature and vapor behavior inside the mat panels. Particleboard made of hinoki strand resulted in a longer plateau time, a higher plateau temperature and a higher gas pressure generated during hot pressing than those of ring-flaker recycled wood particles. Mixed board resulted in values between those of the two other furnish materials
Bound State Solution of Dirac Equation for Generalized Pöschl-Teller plus Trigomometric Pöschl-Teller Non- Central Potential Using SUSY Quantum Mechanics
Get PDFThe bound state solution of the Dirac equation for generalized Pöschl-Teller and trigonometric Pöschl-Teller non-central potentials was obtained usingSUSY quantum mechanics and the idea of shape invariance potential. Theapproximate relativistic energy spectrum was expressed in the closed form. Theradial and polar wave functions were obtained using raising and lowering ofradial and polar operators. The orbital quantum numbers were found from thepolar Dirac equation, which was solved using SUSY quantum mechanics and theidea of shape invariance
Antibacterial Curcuma xanthorrhiza Extract and Fractions
Get PDFAn acetone extract of Curcuma xanthorrhiza rhizomes and the n-hexane and chloroform fractions obtained from it were tested on eight pathogenic bacteria. The results showed that the acetone extract and the nhexane fraction exhibited significant activities against Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus, and weak activities against Shigella dysenteriae and Vibrio cholerae. They were inactive against Escherichia coli, Enterobacter aerogenes and Salmonella thypi, while the chloroform fraction was devoid of activities. NMR analysis disclosed the presence of α-curcumene, xanthorrhizol and an unknown monoterpene in the nhexane fraction. In the chloroform fraction, curcumin was found to be the main compound, together with xanthorrhizol as a minor compound. These results suggest that the antibacterial potency of acetone extract of C. xanthorrhiza is contained in the n-hexane fraction, in which the active constituents are terpenoid compounds. This is the first report of the use of NMR analysis for compound identification contained in an extract or fractions of C. xanthorrhiza
Optimization Models for the Control of Saltwater Intrusion
Get PDFA general optimal control model was developed for the control of saltwater intrusion in coastal aquifer systems. The underlying sharp-interface and density-dependent hydraulic and water quality response equations are presented. Different solution algorithms are described for the control problem, including the imbedding method, Box's algorithms, and the linked simulation-optimization methodology (LSO). Several field applications are presented. The optimization approach, despite requiring significant computation resources, is superior to conventional simulation methods. Optimization produces not only locally optimal planning, design, and operational policies, but also tradeoffs associated with environmental and hydraulic objectives
Promoting Dolichoderus thoracicus as an Agent to Disperse Trichoderma sp., a Fungus that Controls the Black Pod Disease, Central Sulawesi, Indonesia
Get PDFIn this study, we propose to use Dolichoderus thoracicus to act as a double agent; not only as an agent to control cocoa plant pests, but also as an agent for distributing Trichoderma sp., a fungus that suppresses the development of the black pod disease caused by Phytophthora palmivora. In the experiments, D. thoracicus was more attracted to honey-soil media (M5) and coconut waste pulp-soil media (M6). However, 10% sucrose-potato-soil media (M3) was the best media for growing Trichoderma sp. Morphological study showed that spores attached to many parts of D. thoracicus. The efficiency of D. thoracicus in distributing the spores compared to the conventional method of using a sprayer was measured. The results showed that the growth of P. palmivora was suppressed by 83.33%, which is not significantly different from when Trichoderma was dispersed through spraying (87% suppressed). It was concluded that D. thoracicus can act as a double agent and can be used to disperse Trichoderma sp
Numerical Analytic Solution of SIR Model of Dengue Fever Disease in South Sulawesi using Homotopy Perturbation Method and Variational Iteration Method
Get PDFIn this research, the susceptible"“infected"“recovered (SIR) model of dengue fever is considered. We have implemented two analytical techniques, namely the variational iteration method (VIM) and the homotopy perturbation method (HPM) for solving the SIR model. The Lagrange multiplier was investigated for the VIM and He's polynomial approach for the HPM was used. In these schemes, the solution takes the form of a convergent series with easily computable components. The resultsshow thatthe VIM solution is more accurate than the HPM solution for short time intervals, whereasthe HPM is more accurate than the VIM for long time intervalswhencompared with the fourth-orderRunge-Kutta method (RK4).We found that the HPM and the RK4 were in excellent conformance
Constrained Two-Dimensional Inversion of Gravity Data
Get PDFThe non-uniqueness in the solution of gravity inversion poses a major problem in the interpretation of gravity data. To overcome this ambiguity, "a priori" information is introduced by minimizing a functional that describes the geometrical or physical properties of the solution. This paper presents a 2D gravity inversion technique incorporating axes of anomalous mass concentration as constraints. The inverse problem is formulated as a minimization of the moment of inertia of the causative body with respect to the axes of the mass concentration. The proposed method is particularly applicable to homogeneous, linear mass distributions, such as mineralization along faults and intruded sills or dikes. Inversions of synthetic and field data illustrate the versatility of the implemented algorithm
Modeling Haze Problems in the North of Thailand using Logistic Regression
Get PDFAt present, air pollution is a major problem in the upper northern region of Thailand. Air pollutants have an effect on human health, the economy and the traveling industry. The severity of this problem clearly appears every year during the dry season, from February to April. In particular it becomes very serious in March, especially in Chiang Mai province where smoke haze is a major issue. This study looked into related data from 2005-2010 covering eight principal parameters: PM10 (particulate matter with a diameter smaller than 10 micrometer), CO (carbon monoxide), NO2 (nitrogen dioxide), SO2 (sulphur dioxide), RH (relative humidity), NO (nitrogen oxide), pressure, and rainfall. Overall haze problem occurrence was calculated from a logistic regression model. Its dependence on the eight parameters stated above was determined for design conditions using the correlation coefficients with PM10. The proposed overall haze problem modeling can be used as a quantitative assessment criterion for supporting decision making to protect human health. This study proposed to predict haze problem occurrence in 2011. The agreement of the results from the mathematical model with actual measured PM10 concentration data from the Pollution Control Department was quite satisfactory