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In the present research work, dissimilar metal joints of nickel-based superalloy (IN718) and low-alloy steel (EN24) round bars were carried out by using continuous drive friction welding. The joining of specimens was performed by varying friction time in the range of 2-10 s and keeping other welding parameters (friction pressure, 50 bar; upset pressure, 80 bar; upset time, 3 s; and rotational speed, 1400 rpm) constant. The main focus is to understand the characteristics of weld interface (WI), burn-off length and mechanical behavior of weld samples. It is noteworthy that significant changes in the microstructure caused variation in hardness across the weld interface. Moreover, it was observed that burn-off length increased linearly from 4.2 to 12.9% with increasing friction time. The tensile test results revealed that joint efficiency ~ 100% can be achievable by selecting the appropriate parameters. [ABSTRACT FROM AUTHOR]

A novel, convenient and economical method was developed for the anodic thiocyanation of nitrogen-containing aromatic and heteroaromatic compounds by constant potential electrolysis of potassium thiocyanate in an undivided cell under mild condition (25°C, Pt anode, CH3CN) with yields up to 91%. The products were characterized by spectroscopic methods and a mechanism was deduced from voltammetry studies. The salient features of proposed procedure ensures mild reaction conditions, shortest reaction time, accelerated rate, high yield, cost-effectiveness, selectivity, and simple work up procedure, Which provide additional advantages in the context of green chemistry. [ABSTRACT FROM AUTHOR]

Continuous-drive rotary friction welding was performed to join cylindrical specimens of carbon steel (EN24) and nickel-based superalloy (IN718), and the microstructures of three distinct weld zones—the weld interface (WI)/thermo-mechanically affected zone (TMAZ), the heat-affected zone (HAZ), and the base metal—were examined. The joint was observed to be free of defects but featured uneven flash formation. Electron backscatter diffraction (EBSD) analysis showed substantial changes in high-angle grain boundaries, low-angle grain boundaries, and twin boundaries in the TMAZ and HAZ. Moreover, significant refinement in grain size (2–5 μm) was observed at the WI/TMAZ with reference to the base metal. The possible causes of these are discussed. The microhardness profile across the welded joint shows variation in hardness. The changes in hardness are ascribed to grain refinement, phase transformation, and the dissolution of strengthening precipitates. The tensile test results reveal that a joint efficiency of 100% can be achieved using this method. [ABSTRACT FROM AUTHOR]

Clean, practical, and efficient electrochemical synthesis of pharmaceutically relevant 4H-pyran derivatives by one-pot three-component combination of an aryl aldehyde, malononitrile, and a dicarbonyl compoundis developed. The synthesis is performed in ethanol with lithium perchlorate as a supporting electrolyte in an undivided cell on a platinum electrode under constant potential electrolysis conditions. [ABSTRACT FROM AUTHOR]

A facile and Eco-compatible synthesis of benzofuran derivatives (4a-4h) has been carried out at platinum electrode by electrochemical oxidation of catechol in the presence of active methylene groups. Electro- organic synthesis has been performed in an undivided cell at ambient conditions. The products of electrolysis have been purified and characterized by FTIR, 1H NMR and 13C NMR and mechanism was deduced by voltammetric studies. [ABSTRACT FROM AUTHOR]

The genetic diversity among five populations (Bhadbada reservoir, Mohinisagar reservoir, Bansagar reservoir, Bargi reservoir and Gandhisagar reservoir) was revealed using random amplified polymorphic DNA markers. 10 random primers screened, 5 primers revealed various banding patterns and yielded 71 total loci as an average of which 39.60 (55.77%) were polymorphic between the population and 86.84% within the population of Sperata seenghala. Population wise the highest genetic polymorphism was obtained in Bhadbada reservoir as 67.61% whereas the lowest was in Gandhisagar reservoir as 49.30%. However, Analysis of Molecular Variance indicated low genetic diversity (Hpop = 0.0921 ± 0.1249; I = 0.1584 ± 0.1942) in Bansagar reservoir. Relative genetic differentiation (GST = 0.3993) and restricted gene flow (Nm = 0.7523) as an average indicated low gene diversity among the fish populations. The un-weighted pair group method with averages (UPGMA) dendrogram showed 05 major clusters, each cluster representing a population. Fish population of Mohinisagar reservoir showed high genetic distance (0.3981) with respective Bargi reservoir population and highest genetic identity (0.8846) reflected between Bansagar and Gandhisagar reservoir. Highest genetic distance between Mohinisagar and Bargi reservoir fish populations shows no significant correlation between genetic and geographical distance of the genotypes collected from different lentic and geographical isolated water bodies. This investigation indicated that lowest genetic diversity existed in different geographic populations of S. seenghala. All the five populations were found to be low in genetic variation, which is useful information for future conservation measures of S. seenghala confined in natural water bodies of Madhya Pradesh. [ABSTRACT FROM AUTHOR]

The electroorganic synthesis of 5-substituted-2-amino-1,3,4-oxadiazoIes from semicarbazone and 5-substituted-2-amino (substituted amino)- 1,3,4-oxadiazoles from acylhydrazines and isothiocyanates were carried out at platinum electrode. This is an environmentally benign method in the field of electroorganic reactions under controlled potential electrolysis at platinum electrode in an undivided cell. The use of a non-aqueous solvent and supporting electrolyte facilitate cyclization on platinum electrode in this technique. The details of this synthetic method are described in the text. [ABSTRACT FROM AUTHOR]