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ANALYSIS AND OPTIMIZATION OF FRICTION WELDING PARAMETERS FOR AA6061-AA2014 DISSIMILAR JOINTS
Get PDFFriction welding is a solid state welding used owing to its properties such as low heat input, high production efficiency and environment friendliness. Materials which aredifficult towelded by fusion welding processes can be successfully done friction welding. In this work, an effort was made to predict the maximum tensile strength of friction welded AA 6061 and AA 2014 aluminium alloy dissimilar joints incorporating the process parameters such as rotational speed, friction pressure and forging pressures which have immense on the strength of joints. The friction welding process parameters were optimized to achieve maximum tensile strength of the joint. The maximum tensile strength of 210MPa  for the joints fabricated under the welding conditions ofrotational speed 1508 rpm, friction pressure of 8.16 MPa/secand forging pressure of 6.79 MPa/sec using the optimization techniques
Design and Development of Network Reliability based Secure Multicast Routing Protocol for MANET
Get PDFIn Mobile Ad hoc network (MANET), link quality and stability of links as well as nodes play a major role. In ad hoc network, links are often changing which could affect the node mobility and integrity of data packets. In this research work, Network Reliability based Secure Multicast Routing Protocol (NRSMRP) is proposed to achieve network reliability by means of creation of reliable multicast tree. This multicast tree is constructed based on link quality and reliability trust metric. In first phase, node categorization and reliability metric calculation are implemented with the help of link quality. In second phase, reliable multicast tree is formed based on parent node and child node. Parent node must have god capacity and signal strength to communicate with child node. In last phase, authentication based multicast routes are established based on the calculation of direct reputation of mobile nodes. From the results, proposed protocol achieves better performance than existing schemes
DIMINUTION OF HEAVY METALS IN INDUSTRIAL SOLID WASTE BY AN AMALGAMATION OF MYCO AND VERMI REMEDIATION
Get PDFDue to the development of Industrialization and urbanization, a wide variety of industrial and consumer products, by products and solid waste has been produced. The solid waste generated constitutes the hazardous substance which possesses certain impacts on humans and their environment. In that heavy metal pollution from industries are the serious environmental problems. Rapid development in industries in the last few decades resulted in the strenuous task for finding to manage the waste generated. These hazardous solid wastes have been formulated into reusable end product by the process of bioremediation. Bioremediation is a natural process, which involves the use of organism to remove or neutralize the toxic pollutant from the contamination site. This review focus on the toxic effects of heavy metals on the environment and on the human health as well as the possible bioremediation method of these metals using fungus and earthworm. In order to conserve the environment and resources, the biological remediation by both fungus and earthworm for heavy metals and their efficiency have been summarised in detail
A Study on Surface Roughness and Cutting Width for Circular Contour Machining of Stir Cast AA6063/SiC Composites in WEDM
Get PDFWire electrical discharge machining is used in machining electric conductive materials with intricate shapes and profiles. This paper presents an experimental investigation on the influence of cutting conditions of WEDM on surface roughness and cutting width of machining of AA6063/SiC composites. Here a semi cylindrical piece is removed from a rectangular plate of AA6063/SiC composites plate fabricated with reinforcing SiC in 0%, 5%, 10% and 15% weight fractions through stir casting. The effect of WEDM parameters such as pulse on time, pulse off time and peak current on surface roughness and cutting width on different composition of AA6063/SiC were analyzed for circular contour machining. The experimental results show that increase in percentage of SiC has high influence in mechanical behavior of AA6063/SiC composites and the effect of pulse on time is very significant in reducing the surface roughness and pulse off time plays an important role in producing minimum cutting width.
 
Low Error Rate Data Transmission in Cognitive Radio Networks
Get PDFCognitive Radio (CR) has become a hopeful technology to enhance the spectrum utilization through spectrum sharing between licensed user (primary user) and unlicensed user (secondary user). An vital rule mandated for the development of such frameworks are to develop solutions that don’t require any changes to the existing primary user (PU) infrastructure. An Orthogonal Frequency Division Multiplexing (OFDM) is typically worn advancements in present wireless communication systems which has the possibility of fulfilling the demand for cognitive radios intrinsically or with slight changes. In this paper, Space time block codes is used. The various antennas used on both ends for trustworthy data broadcast and interference nulling schemes. These codes can accomplish full broadcast diversification determined via the number of broadcast antennas. The MIMO is worn for enhancing the power of a wireless link, to determine the issue for lower BER and achieve a superior performance
Soft Computing Based Cavity Temperature Control of Plastic Injection Molding system
Get PDFThe plastic parts having complex three dimensional structures are produced by Plastic injection molding system. Thequality of the product is determined by controlling the temperature of the mold cavity. The mold cavity temperature controlwith the conventional ON/OFF, PI, and PID controllers have several disadvantages. This paper proposes the method toreduce settling time and undershoot in cavity temperature control with selected evolutionary algorithms. The controllerparameters are optimized with Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) Algorithm for PID and I-PDcontrollers by considering Mean Square Error (MSE) as fitness function. Compared to conventional methods theparameter optimization using soft computing methods such as GA and PSO improves the performance indices of PID andI-PD controllers
DESIGN, SYNTHESIS AND COX1/2 INHIBITORY ACTIVITY OF NEW QUINAZOLINE-5-ONE DERIVATIVES
Get PDFA new series of 1-(4-Acetylphenyl)-7,7-dimethyl-3-(substitutedphenyl)-1,2,3,4,7,8-octahydroquinazolin-5(6H)-ones (6-15) were synthesized and tested against COX-1 and COX-2 enzymes. Those compounds exhibited strong interaction at the COX-2 binding site and poor interaction at the COX-1 active site. Subjected to in vitro cyclooxygenase COX-1/COX-2 inhibition assay; most of the compounds especially compounds 6, 7, 12, 13, and 16 exhibited potent anti-inflammatory effects, selective COX-2 inhibition, with half-maximal inhibitor concentration (IC50) values of 0.22–1.42 μM and selectivity index (SI) values of 6.16–14.18 compared with celecoxib (IC50 = 0.05 μM and COX-2 SI: 296), diclofenac (IC50 = 0.8 μM and COX-2 SI: 4.87), and indomethacin (IC50 = 0.49 μM and COX-2 SI: 0.08) as reference drugs. Docking study has been carried out to confirm the binding affinity and selectivity of the most active compound (compound 6) to COX-2 enzyme
Design, Molecular Modeling and Synthesis of Some New Purine-diones and Pyridopyrimidine-diones with Anticancer Activity
Get PDFAn olomoucine analogues of 2-[(1-substituted)-2,6-dioxo-2,3,6,7–tetrahydro-1H-purin-8-ylsulfanyl]-N-substituted acetamide 6a-g and 7a-g, 1-substituted-8-[2-(4-substituted phenyl)-2-oxoethylsulphanyl]-3,7-dihydro-1H-purine-2,6-diones 9a-g and 10a-g, 3-(2-substituted benzyl)-6-(4-substituted phenyl)-1H-thiazolo[2,3-f]purine-2,4-dione 11a-g and 12a-g and their isosteres 3-substituted benzyl-5-methyl-7-substituted-1H-pyrido[2,3-d]pyrimidine-2,4-dione 13a-c and 14a-c were designed and synthesized. The target compounds 11a-g and 12a-g were prepared by cyclodehydration of 9a-g and 10a-g in PPA, while 13a-c and 14a-c were synthesized by condensation of 6-amino-3-(2-substituted benzyl)-1H-pyrimidine-2,4-dione 1a or 1b and the appropriate acylacetone in glacial acetic acid. Structures of the new compounds were verified on the basis of their IR, 1H NMR, MS, HRMS and elemental analyses. The newly synthesized compounds were tested for their anticancer activity and most of the tested compounds showed good to excellent inhibition activity against the tested human breast cancer cell line MCF-7 in comparison to doxorubicin as a reference drug.
KEYWORDS: olomoucine; cyclin-depenent kinase; synthesis; anticancer
 
Kinetic Study of the Dissolution of Tunisian Natural Phosphate or Francolite in Industrial Phosphoric Acid
Get PDFA kinetic study of dissolution of Tunisian natural phosphate or francolite whose particles have a mesoporous texture inindustrial phosphoric acid is carried out. Therefore, We focused on the study of the influence of certain parameters thatare close to those used in plants producing phosphoric acid which are the stirring speed (300, 500 and 700 rounds perminute), concentration of phosphoric anhydride (25, 30 and 35 percent of P2O5), and the temperature (60, 70 and 80degrees Celsius); we note that the rate of dissolution of this phosphate rises by increasing the precedent parameters.Because of the complexity of the study of the dissolution of phosphate in mineral acids. Several different published kineticmodels giving different expressions of speed versus time. The shrinking core model is the appropriate model used in ourwork in a solution where there is no calcium sulfate to calculate the rate constant k and the activation energy Ea = 3.3946Kcal/mol of this phosphate
THE INHIBITION AND ADSORPTION PROPERTIES OF DTPMP TSC ON STAINLESS STEEL IN ACIDIC MEDIUM
Get PDFThe inhibition effect of diethylenetriamine penta(methylene phosphonic acid) (DTPMP) and Trisodium Citrate (TSC) on thecorrosion behavior of stainless steel in 0.5 M H2SO4 solution was investigated by using weight loss method. The combinedcorrosion inhibition efficiency offered 200 ppm of DTPMP and 150 ppm of TSC was 95%. Polarization study showed thatthe inhibitors inhibit stainless steel corrosion through mixed mode and electrochemical impedance spectroscopy (EIS)results confirm the adsorption of the inhibitors at stainless steel/acid interface. The adsorption of DTPMP and TSC ontothe stainless steel surface was found to follow Langmuir adsorption isotherm modes. Negative values of (ΔGads) in theacid media ensured the spontaneity of the adsorption process. The nature of the protective film formed on the metalsurface has been analyzed by FTIR spectra, SEM and AFM analysis. The activation energy (Ea), free energy change(ΔGads), enthalpy change (ΔHads) and entropy change (ΔSads) were calculated to understand the corrosion inhibitionmechanism