Yanbu Journal of Engineering and Science (YJES)
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SYNTHESIS AND ANTIMICROBIAL ACTIVITIES OF SOME 4-(6-METHYL-2- NAPHTHYL)-5,6-DIHYDRO-6-(SUBSTITUTED PHENYL)-4H-1,3-OXAZINE-2-AMINES
No full textSome 4-(6-methyl-2-naphthyl)-5,6-dihydro-6-(substituted phenyl)-4H-1,3-oxazine-2- amines have been synthesised by hydroxyapatite catalyzed solvent-free cyclization of 6- methyl-2-naphthyl chalcones and urea under microwave irradiation. The yields of the oxazine were more than 85%. The synthesised oxazine amines have been characterized by their physical constants, analytical and spectroscopic data. The antimicrobial activities of all prepared 4-(6-methyl-2-naphthyl)-5, 6-dihydro-6-(substituted phenyl)-4H-1,3- oxazine-2-amines have been evaluated using Bauer-Kirby disc diffusion method with a variety of bacterial and fungal strains
SYNTHESIS, SPECTRAL, THERMAL DECOMPOSITION, KINETIC AND ANTIMICROBIAL STUDIES OF AZO-SCHIFF BASES
No full textIn this work we focused on the synthesis of new Azo-Schiff bases which were prepared by condensation of 3-formyl-4-hydroxy phenylazo benzene with both 1,4-Bis (3- aminopropyl) piprazine, thiocarbohydazide respectively. The Schiff bases were analyzed by different spectral techniques (LC-MS, GC-MS, 1H-NMR, IR). The new Azo-Schiff Bases were studied for antibacterial activities against gram positive (Bacillus subtilis and Staphylococcus aureus) and gram negative (Salmonella typhi and Escherichia coli) agents. The azo compound ligand exhibited a variable activity of inhibition on the growth of the bacteria. The compounds were subjected to simultaneous thermogravimetric analysis to study their decomposition mechanism and thermal stability
SYNTHESIS AND ANTIMICROBAIAL EVALUTION OF 3-ISOBUTYL-2,6-DI(THIOPHENYL-3) PIPERIDIN-4-ONE DERIVATIVES
No full textIn awide a program of extensive search for new and efficient antimicrobial agents,3- isobutyl -2,6-di(thiophenyl-3)piperidin-4-one(1) and its derivatives (2-4) were synthesized and characterized by IR,LC-MS,\u27H-NMR, C-NMR.The synthesized compounds 1-5 were tested for their antibacterial activity in vitro against streptococcus bacillus subtilis, Esherichia coli, pseudomonas, and Klebsiella peumoniae. as the standard drug streptomycin was used
A NEW APPROACH OF SYRUP MANUFACTURING USING FUZZY TIME CONTROL DISCRETE EVENT SYSTEM
No full textPharmaceutical industries of the world are manufacturing their most of the goods in syrup form. The proposed study relates with the designing of medicated syrup manufacturing, using the fuzzy time control discrete event system. The system is designed with three inputs; viscosity, specific gravity, and chemical selection. And eight outputs temperature, temperature time, mixing speed, mixing time, valve, valve opening time, PH at current liquid temperature, and PH time. System is controlled by controlling the four parameters; valve selection, temperature monitoring unit, mixing motor, and PH control unit. System takes feed back from four sensors and time control rules are formulated and simulated using MATLAB tool box.
PREPARATION AND CHARACTERIZATION OF MICA-REINFORCED POLYPROPYLENE COMPOSITES
No full textThis paper reports the preparation of mica-reinforced polypropylene composites by twin- screw extrusion and characterization of various properties. The composites were prepared by the varying weight percentages of the filler up to 40%. Structural identification was carried out by Fourier Transform Infra-red spectroscopy and shifting of few functional groups was noted. Mechanical properties such as stress-strain measurements and impact properties showed minimal interaction between the filler and matrix owing to the difference in morphology of the components. Differential Scanning Calorimetry results showed nucleation by the filler in the composites
UNIFIED POWER FLOW CONTROLLER CONTROL STRATEGIES for POWER FLOW
No full textIn order to address power flow control issues, this study introduces the use of Unified Power Flow Controller (UPFC) models. These models are based on regulating the variables influencing the transmission line’s power flow, and they are capable of controlling the bus voltage, the line’s actual and reactive power, all at once and independently. The idea behind the UPFC technique proposed in this paper is to provide the unique functional capability of independently controlling both the real and reactive power flow in the line. The in-phase component of the series injected voltage dominates the reactive power while the quadrature component affects the real power. A conventional controlling steady-state analysis and dynamic stability analysis of the power system is developed based on the UPFC model. UPFC provides real-time controlling of all or any combination of the power system parameters which determine the transmittable power. UPFC can force and maintain strategically chosen values of the active power and the reactive power at a given point of the line by PI control
SYNTHESIS AND ANTIOXIDANT ACTIVITIES OF SOME 1N-ACETYL-3-(3- HYDROXYPHENYL)-5-(SUBSTITUTED PHENYL)-4, 5-DIHYDRO1H-PYRAZOLINES
No full textA series containing sixteen titled pyrazoline derivatives have been synthesized by perchloric acid catalyzed cyclization cum acetylation of 3-hydroxyphenyl chalcones, hydrazine hydrate and acetic anhydride by refluxing condition. The yields of the synthesized N-acetylpyrazolines were found to be more than 90%. These 1-acetylpyrazolines were characterized by their physical constants and spectral data. The antioxidant activities of these pyrazolines derivatives have been evaluated by 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity
OPTIMIZATION AND SIZING OF AN ISLAND MICROGRID BASED ON PHOTOVOLTAIC/FUEL CELL (PV/FC) IN KSA
No full textThe major goal of this research manuscript is to conduct economical and feasibility studies of an island photovoltaic/fuel cell (PV/FC) hybrid system. It has been designed to feed electricity to a remote area positioned in albaha zone in Kingdom of Saudi Arabia. To achieve this mission, all system devices are modelled and simulated via optimization mechanisms. An objective function is formulated relied on the total annual cost (TAC). An optimization mechanism, the Flower Pollination Algorithm (FPA) has been applied to obtain the optimum number of the photovoltaic (PV) panels, the electrolyzers; the H₂ storage tanks the fuel cells (FCs) and the number of batteries for the proposed system with the least total net present value (TNPV) of the hybrid system. The loss of power supply probability (LPSP) has been utilized to improve the performance of the proposed system. The premier estimation fluctuation effect of the FC, the electrolyzer and the H2 storage tanks on the levelized cost of energy (LCOE) has been applied in the sensitivity test
TECHNO-ECONOMIC FEASIBILITY OF A HYBRID SOLAR PV AND WIND POWER SYSTEM FOR YANBU, SAUDI ARABIA
No full textEnergy from renewable sources is being increasingly exploited for meeting the power demands and reducing the harmful impact of burning the fossil fuels on the environment. Solar photovoltaic and wind turbine are being incorporated with the conventional diesel generator to reduce the fuel consumption. Saudi Arabia, being a country with high intensity of solar radiation, has good potential of using solar PV system. In this study, a solar wind hybrid system is modeled using HOMER to find an optimum system to meet the load requirement of a community at Yanbu city. The primary load of the community of 500 people is 556 kWh/day with 68 kW peak. The analysis showed that 200 kW PV system is the most economically feasible to meet the proposed demand and the minimum cost of energy for this system is 0.617 $/kWh. Sensitivity analysis was carried out by varying average wind speed and solar radiation and is presented in this study
PRELIMINARY EVALUATION OF EGNOS PERFORMANCE FOR GIS APPLICATIONS
No full textEuropean Geostationary Navigation Overlay Service (EGNOS) is a Satellite Based Augmentation System (SBAS) being developed by European Space Agency (ESA) to make GPS and GLONASS suitable for civil aviation and other applications. It improves the accuracy of the GPS and GLONASS signals to about 1 to 2 meters. Though corrected signals from EGNOS are receivable in Saudi Arabia, the accuracy of the signals might be degraded due to the far distance between Saudi Arabia and the ground monitoring stations. The precision and availability of the signals are also expected to be reduced. This paper assessed the EGNOS signal receivable in Saudi Arabia by using handheld GPS (Trimble GeoXH 2005) with GPS software (Trimble GPS Controller 2.3 and ArcPad 7). The GPS data was collected in selected Saudi cities that included Jeddah, Khobar, Madinah and Yanbu. This study also examined the possibility of using EGNOS signals for GIS applications. The results indicate that EGNOS correction improved the accuracy of the signals to about 1.5m and lowest precision of about 5m (mean distance). The results show variations from one city to the other. The drawbacks were availability and precision. So, it cannot be used for time-critical projects unless the availability and precision are improved