Spectrophotometric determination of palladium using 2-hydraziniopyridine

Rapid, simple, sensitive and validated spectrophotometric method has been described for the determination of palladium (II) using 2-hydrazinopyridine. The complex product was quantitatively measured at 510 nm and the reaction conditions were studied and optimized. The stoichiometry and the stability constant of the purple colored complex has been determined spectrophotometrically in aqueous solution at 25 oC using Job’s continuous variation and the molar ratio methods. The complex has 1:1 (M:L) molar ratio and Beer’s plot was linear in the concentration ranges 1.06-9.00 μg/mL with corresponding molar absorptivity 2.978×103 L/mol.cm. The limits of detection and Sandell’s sensitivity were also evaluated. The accuracy was evaluated as the % recovery (96.61-102.58) and precision was evaluated as RSD% (0.04-0.41) using inter-day and intraday analyses of multiple samples. The effect of various diverse ions on the determination of Pd(II) has been investigated

Anti-Alzheimer and Anti-cox2 Activities of the Newly Synthesized 2,3’-Bipyridine Derivatives (I)

3-Aryl-1-pyridin-3-ylprop-2-en-1-ones 1a,b reacted with2-cyanoethanethioamide (2) to afford the corresponding4-aryl-6-thioxo-1,6-dihydro-2,3’-bipyridine-5-carbonitriles6a,b. The synthetic potentiality of compounds 6a,b wasinvestigated in the present study via their reactions withseveral active-hydrogen containing compounds 8a-g aimingto synthesize 4-aryl-6-pyridin-3-ylthieno[2,3-b]pyridin-3-amines 10a-n via 6-(alkylthio)-4-aryl-2,3’-bipyridine-5-carbonitriles 9a-n. The structures of all newly synthesizedheterocyclic compounds were elucidated by considering the data of IR, 1H NMR, mass spectra as well as that of elementalanalyses. Anti-Alzheimer and anti-cox2 activities for all newly synthesized heterocyclic compounds were investigated

Synthesis, reactions and characterization of 2-methylthionicotino-nitrile, pyrazolopyridine and pyridopyrazolotriazine derivatives

4,6-Diaryl-1H-pyrazolo[3,4-b]pyridin-3-amines 4a-c wereobtained in very pure state and used as the good startingmaterials for the present study. Compound 4a diazotized to give the corresponding diazonium salt 11 and also, reacted with 2-bromo-1-phenylethanone to give the corresponding pyrazolo[3,4-b]pyridin-2-yl)-1-phenylethanone derivative 7 which in turn, used for the preparation of the hydrazone and formamide derivatives 8 and 10 respectively through its reaction with hydrazine hydrate and formic acid respectively. Compound 11 was used for the preparation of pyridopyrazolotriazine derivatives via its coupling with several active –CH2- containing compounds.Considering the data from IR, 1H NMR, the mass spectra and elemental analyses the chemical structures of the newly synthesized heterocyclic compounds were elucidated

The Effect of Tool Path Strategy on Twist Behavior In Single Point Incremental Sheet Metal Forming

In Incremental sheet metal forming process, one important step is to produce tool path, an accurate tool path is one of the main challenge of incremental sheet metal forming process. Various factors should be considered prior to generation of the tool path i.e. mechanical properties of sheet metal, the holding mechanism, tool speed, feed rate and tool size. In this work investigation studies have been carried out to find the different tool path strategies to control the twist effect in the final product manufactured by single point incremental sheet metal forming (SPIF), an adaptive tool path strategy was proposed and examined for several Aluminum conical models. The comparison of the proposed tool path with the conventional iso planar and helical tool paths shows that there is no effect of twisting in the final model when using adaptive tool path, while the twisting effect are clearly observed and measured in the final product when using both iso planar and helical tool path When forming 80 and 110mm depth conical cup. The time of forming has been measured and its observed that in adaptive tool path the time of forming is less than 8.7 %from the helical tool path when forming conical cup with 50mm depth and less than of 8.91% when forming conical cup with 110mm dept

The Effect of Tool Path Strategy on Mechanical Properties of Brass (65-35) in Single Point Incremental Sheet Metal Forming (SPIF)

In this paper, three tool paths strategies; iso-planar, helical and adaptive have been implemented to investigates their effect on the mechanical properties of Brass 65-35 formed by single point incremental sheet metal forming process. To response this task, a fully digital integrated system from CAD modeling to finished part (CAD/CAM) for SPIF process has been developed in this paper. The photo-micrographs shows an identical grain formation due to the plastic deformation of the incremental forming process, change in the grain shape and size was observed. It's found that the adaptive tool path play a significant role to increase the hardness of the formed specimen from (48 to 90 HV) and the grain texture of the formed specimen found as round shape, while the hardness is increased in little amount from (48 to 74 HV) in the specimen formed using helical and it’s grain texture was found as needle shape

Improvement of Resistance Spot Welding by Surfaces Treatment of AA1050 Sheets

Resistance spot welding (RSW) aluminum alloys has a major problem of inconsistent quality from weld to weld, because of the problems of the non-uniform oxide layer. The high resistivity of the oxide causes strong heat released which influence significantly on the electrode lifetime and the weld quality. Much effort has been devoted experimentally to the study of the sheet surface characteristics for as-received sheet and surface pretreatment sheet by pickling in NaOH and glassblasted with three thicknesses (0.6, 1.0, and 1.5 mm) of AA1050. Three different welding process parameters energy setup as a low, medium, and high were carried. Tensile-shear strength tests were performed to indicate the weld quality. Moreover, microhardness tests, macro/micrographs, and SEM/EDS examinations were carried out to analyze, compare, and evaluate the effect of surface conditions on the weldability. The as received sheet showed a higher electrical contact resistance because of its thicker and non-uniform oxide layer. In contrast, the glass-blasted sheet showed lower value, since it has a roughest surface, which leads to easy breakdown the oxide layer. The highest average values and least scattering of the maximum load fracture are with treated sheet by pickling in NaOH, these values are 760, 1193, and 2283 N for 0.6, 1.0, and 1.5 mm sheet thickness respectively for medium input energy. In contrast, the minimum values with glass-blasted sheet are 616, 1008, and 2020 N for 0.6, 1.0, and 1.5 mm sheet. The microhardness profiles of the fusion zone and HAZ is the lower than the base metal for all cases. Numerical simulation with SORPAS® was used to simulate and optimize the process parameters, and it has given good results in prediction when they compared with experiments