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Photocatalysis with ecofriendly and low cost materials is attractive for degradation of organic pollutants without aid of strong reagents. In this regard, Au nanoparticle decorated ZnO nanorods (Au–ZnO) with good crystalline quality was synthesized by cost-effective and scalable hydrothermal method followed by photo-reduction of Au salt. This study addresses variation of photocatalytic degradation kinetics of different nature of dyes with various scavengers and pH conditions. Further, the process versatility is demonstrated by selective or simultaneous degradation of binary dye mixtures with optimized parameters. From Langmuir-Hinshelwood kinetic model, dye concentration range for first order limiting case was determined, and further validated from measured surface area of photocatalyst and change in dye absorbance before irradiation. Better adsorption with faster degradation exhibited by Methylene Blue (MB) dye showed efficient mineralization, revealed from chemical oxygen demand measurements. In Au–ZnO photocatalysis, generation of hydroxyl radical and its significant role in dye degradation was demonstrated using different scavengers. Variation of dye adsorption with pH dependent surface charge characteristics of photocatalyst resulted about one order higher degradation rate constant of MB at high pH. Strong pH dependent MB degradation is shown to be useful for its selective or simultaneous degradation with other dyes. Results of this study are useful for designing photo-reactors and these nanoparticles are efficient for degradation of different dyes, their combinations and industrial effluents under low power UV lamp for treatment different organic pollutants.

Background: A series of phenylurea derivatives were designed and synthesized, The target compounds were subjected to pharmacological studies. Various other parameters such as physicochemical properties, computational studies, and % similarity were also calculated. Materials and Methods: The synthesis of the target compounds has been carried out by reaction of Phenylurea with chloroacetyl chloride to afford 1-(2-chloroacetyl)-3-phenylurea, which further reacted with substituted anilines. All the reactions were monitored by TLC. All the target compounds were purified by recrystallization and characterized by spectroscopic methods. Physicochemical parameters and Log P values of the synthesized derivatives were also calculated. It identified compounds that have the prospect to cross the blood-brain barrier (BBB) and are CNS active. Skeletal muscle relaxant activity was also carried out using the Rotarod method. Results: The data of Log P indicated that the synthesized compounds have the potential to cross the BBB, so they are CNS active. Pharmacological activities of the derivatives showed that the compounds containing chloro group have moderate skeletal muscle relaxant activity. The test compounds possess significant differences between the control group and the treated group. Conclusion: The synthesized derivatives containing chloro group were found to be more potent when compared to standard drug Diazepam. Various others parameters studied revealed that the drug has the potency to cross the blood-brain barrier.

This paper describes an experimental corrosion study performed on austenitic stainless steel deposited mild steel substrate in 0.5 M sodium chloride medium. The study was performed with an aim to improve the corrosion resistance of mild steel substrate through surface deposition of a thin film of asutenitic stainless steel. The thin SS film was deposited by pulse laser deposition technique while using 316 L grade stainless steel foil as a target. Thin film deposition of 316 L stainless steel on mild steel brought about relative improvement in its resistance against corrosion. However, with respect to 316 L stainless steel foil, the specimen exhibited poor corrosion resitance in terms of corrosion rate (corrosion current density), lack of passivity and pitting potential. The reason for the inferior corrosion behaviour of deposited specimen is attributed to defective ferritic microstructure of the thin film and lack of nickel constituent which was associated with lower resistance and higher capacitance with respect to 316 L stainless steel foil. Similarly, with respect to mild steel, deposited mild steel showed better corrosion resistance due to passive role of chromium enriched film.

In aerospace and chemical industries, Ti–6Al–4V alloys are mostly used due to outstanding resistance to corrosion and high specific strength. Gas tungsten arc welding (GTAW) process is generally preferred to join Ti–6Al–4V alloy, but width of bead and heat-affected zone are wider in these joints. To overcome these problems, pulsed current gas tungsten arc welding (PC-GTAW), one of the variants of GTAW process, was employed to join Ti–6A–4V alloy. Recently, gas tungsten constricted arc welding (GTCAW) process, a new advanced variant of GTAW process, was developed. It creates high-frequency current level variation in the arc to produce low heat input, narrow fusion zone and heat-affected zone with deeper penetration compared to conventional GTAW and PC-GTAW processes. The present research work is focused to understand the influence of the post-weld heat treatment on tensile properties, microhardness and microstructure of Ti–6Al–4V alloy joints welded by GTAW, PC-GTAW and GTCAW processes. High frequency resulted in appreciable refinements of prior β grains prime to higher tensile properties, hardness and elongation of joints in the as-welded condition. The post-weld heat treatment (PWHT) at 910 °C resulted in enhancement in elongation and deterioration in tensile strength due to coarsening of α and disintegration of α-martensite into symmetrical α and β. However, pulsed gas tungsten constricted arc welded (P-GTCAW) joints showed greater tensile elongation even in PWHT conditions.

Background: Currently, ringworm treatment drugs include two major categories: first, propylene amine drugs, such as terbinafine, butenafine and naftifine, which exert their bactericidal effects through inhibiting squalene cyclase, causing the lack of ergosterol and accumulation of squalene. The second category of imidazole drugs includes miconazole, econazole, clotrimazole, ketoconazole and bifonazole. Mechanism: These synthetic antifungal agents exhibits their action by inhibiting the lanosterol 14α- demethylation activity of fungal cell, leading to the prevention of the ergosterol synthesis of cell membrane, changing the cell membrane permeability, and resulting in the loss of important intracellular fungal material and causing fungal death. Applications: At present, Imidazole antifungal agents are commonly used drugs in clinical treatment of ringworm with extensive clinical applications. Conclusion: The present review covers the chemistry and detailed pharmacology aspects of luliconazole.

Background: Approach for green chemistry for chemical synthesis is found to be very efficient as it makes the reaction more easily, less tedious, maximize desired products and minimize by-products. Materials & Methods: Utilizing this approach 1, 5-benzodiazepines and its derivatives have been synthesized and evaluated for skeletal muscle and antianxiety activity. 1, 5-benzodiazepine derivatives have attracted great attention due to its diversity of pharmacological activities and its application in heterocyclic synthesis and medicines. The target compounds were synthesized by first reacting o-phenylenediamine with acetophenone to yield 1, 5-benzodiazepines. In the next step the NH of 1, 5-benzodiazepines were chloroacetylated and then the chloro group was substituted with different anilines. The structures were confirmed on the basis of their TLC, IR, 1H NMR and CHN elemental studies. The physicochemical parameters were determined for BBB penetration through online software. Results: The Log P values of the compounds tested showed that compounds have the potential to be CNS active. The compounds were evaluated for the skeletal muscle relaxant activity and antianxiety activity. It was investigated that 1, 5-benzodiazepines derivatives possess significant differences between control group and treated group. Conclusion: Among these derivatives, the compound bearing chloro group possesses the highest skeletal muscle relaxant and antianxiety activity.

Ti–6Al–4V alloys are perfectly suited for fan compressor blade material in advanced aero engine components due to outstanding resistance to corrosion and specific strength was high in both room temperature and elevated temperature. For autogeneous welding of thin sheets of Ti–6Al–4V alloy, the gas tungsten constricted arc welding (GTCAW) was established to be beneficial than the gas tungsten arc welding process. The performance of welded joints depends on the fusion zone grain size (FZG) and fusion zone hardness (FZH), which need to be suitably optimized and controlled to attain advantageous mechanical characteristics of the joint. Hence, in this research study, efforts were taken to develop empirical relationships for predicting the FZH and FZG incorporating very important GTCAW parameters. Parameter optimization was performed using response surface methodology. Additionally, the influence of GTCAW parameters on FZG and FZH was analyzed. From the results, it is inferred that the inter-pulse frequency has better influence on FZG and FZH compared to other parameters.

The investigation was performed on rolled sheets (2 mm thick) of titanium alloy Ti6Al4V joints which are diffusion bonded. The objective of this investigation is to study and analyse the effect of holding time on the diffusion bond characteristics. The time for bonding was kept between 15 and 60 min. The pressure and bonding temperature were maintained constantly at 8 MPa and 900 °C, respectively. Metallurgical characteristics were analysed by optical and scanning electron microscopy. The mechanical properties of the Ti6Al4V alloy joints were evaluated. The strength of the bonds was correlated with the microstructures to study the effect of holding time. The microstructure reveals that the defect-free bond can be produced when holding time is increased to a certain limit. The maximum bonding strength and tensile shear fracture load (TSFL) were attained for a holding time of 60 min yields 138 MPa and 40 kN, respectively.

Titanium and its alloys have been considered as one of the best engineering materials for industrial applications. Excellent combination of properties such as high strength to weight ratio, excellent resistance to corrosion makes them attractive materials for many industrial applications. Recently, considerable research has been performed on Gas Tungsten Constricted Arc welding (GTCAW) process and reported advantages include, lower heat input, reduced residual stresses and distortion. In this investigation, tensile properties of GTCA welded Ti-6Al-4V alloy joints were evaluated. Single pass, autogeneous welds free from volumetric defects were fabricated using optimized GTCAW parameters. The joints were characterized using optical microscopy, scanning electron microscopy and microhardness, survey. Tensile properties of the joints were overmatching with the base metal. The alpha and granular beta grains in the base metal were changed into short acicular alpha martensitic structure in the fusion zone as a result of GTCAW

BACKGROUND A series of new N-(2-benzoyl-4-chlorophenyl)-2-(4-(substituted phenyl) piperazin-1-yl) acetamides (3a-j) have been synthesized by the chloroacetylation of 2-amino-5- chlorbenzophenone which was further reacted with substituted phenylpiperazine. MATERIAL The chemical structures of the compounds were confirmed on the basis of their TLC, IR, 1HNMR, 13CNMR and by elemental analysis. The physicochemical similarity of the target compounds with respect to standard drug diazepam was assessed by calculating from a set of physicochemical properties using software programs. CONCLUSION Molecular docking studies revealed that the target compounds correctly dock into the binding pocket of the GABAA receptor, while their bioavailability/drug-likeness was predicted to be acceptable but requires future optimization. The anxiolytic and skeletal muscle relaxant activity of the target compounds (3a-j) were evaluated in albino mice. Among them, compound 3h showed potent anxiolytic and skeletal muscle relaxant activity.

A series of Schiff bases of diphenylamine derivatives have been synthesized and evaluated in vitro for their antibacterial activity against pathogenic both Gram-positive bacteria B. subtilis and Gram-negative bacteria E. coli using ciprofloxacin as standard drug at conc. of 50 µg/ml and 100 µg/ml. The structures of these compounds were established on the basis of IR and 1H-NMR spectral analysis. The compound (3d) displayed potent antibacterial activity against Bacillus subtilis (17 and 15mm) and Escherichia coli (19 and 17mm) by disc diffusion method.

In modernization nitrogen containing heterocyclic compounds and their derivatives has attracted great interest due to their efficacious biological and pharmacological properties. The moiety of piperazines and substituted aryl piperazines were found to present in compounds aim at evaluating new entities that possess anti-microbial, anti-tubercular, anticonvulsant, anti-depressant, anti-malarial and anti-inflammatory activities. Piperazines show a broad range of activities and are found in many potent biologically active compounds such as thiothixene and pimozide (anti-psychotics), Loxapine (schizophrenia), Clozapine (Atypical anti-psychotics). The modifications in the moiety of piperazine ring shows high efficacy with better potency and lesser toxicity. This review focused on multifarious biological activities related to piperazines and its derivatives.

Concentration dependent interaction between negatively charged citrate capped gold nanoparticles (GNP) and cationic Rhodamine 6G dye was studied from the change in localized surface plasmon resonance (LSPR) absorption due to dye induced nanoparticles aggregation, fluorescence quenching and surface enhanced Raman scattering (SERS) of the dye. The optical properties resulting from their interaction were found to be highly dependent on dilution of the GNP and concentration of the dye. Composites of up to 1 μM dye concentration, relatively low for monolayer coverage on nanoparticles surface, did not result any noticeable change in LSPR wavelength and bandwidth with respect to the pure GNP solution whereas significantly high quenching of the dye fluorescence was observed. In contrast the composites with higher dye concentration were found to exhibit an additional inter-particle coupled LSPR excitation band at higher wavelengths and the characteristics of this absorption band were found to be highly influenced by the dilution of the GNP. The fluorescence quenching efficiency was found to decrease with either increasing the dye concentration or diluting the GNP. Stern–Volmer plots were found to be non-linear at low dye concentrations and almost linear at higher concentrations. The observed fluorescence quenching was attributed to the resonance energy transfer process substantiated by significant change in the excited state lifetime of the dye in the presence of the GNP. Also dye interacting nanoparticles clusters formed on a substrate via solvent evaporation were found to be highly effective for the SERS based detection of very low concentrations of the dye.

Au-ZnO core-shell nanoparticles with cubic Au core were synthesized using ascorbic acid assisted hydrothermal growth method. Variation in optical response, surface plasmon resonance of Au nanocubes during shell layer growth was studied and explained with numerical calculations. Annealing induced changes in optical absorption, crystalline quality and morphology of these nanoparticles was addressed. Annealing at high temperatures (≥ 400 °C) was found to be important for significant improvement of photocatalytic activity of these nanoparticles. Photocatalytic response of the nanoparticles was studied through degradation of methylene blue (MB) and methyl orange (MO) dyes. Role of different process parameters mainly dye concentration, type of UV lamp, nanoparticle loading, presence of different scavengers at varied concentrations and solution pH on dye degradation was addressed. The results reveal that hydroxyl radical plays vital role in the degradation process. The effect of scavengers and their concentration is almost similar for both these dyes degradation. High pH was found to enhance the degradation process and its rate constant increased by 15 and 8 times at pH 12 for MB and MO respectively. These nanoparticles of 1 g/L loading were efficient to degrade the dyes with concentration of about 15 mg/L, within an hour (three hrs.) in high pH (neutral) solutions. The growth process was optimized for easy collection of the nanoparticles for large quantity handling. The core-shell nanoparticles used in the study are environmental friendly and their synthesis along with dye degradation in low power light is cost effective for treatment of industrial wastewater containing different dyes.

An attempt has been made to study the potential of mutagenic effects of gamma rays and sodium azide (NaN3) on the meiotic cells of Vigna unguiculata (cowpea). Cowpea being a self-pollinated vegetable crop has very limited genetic variability therefore induced mutation can provide additional source of mutation in recent plant breeding programmes. Chromosomal aberrations like unorientation, multivalents, laggards, bridges, micronuclei, stickiness and precocious movement etc. were noticed in mutagen treated populations. Chromosomal aberrations were found to be correlated with the concentrations of physical and chemical mutagens individually as well as in combination. On the basis of our experimental results it can be concluded that the combined treatment proved to be more effective in inducing abnormalities and pollen sterility as compared to individual treatment sets.

A tetradentate nitrogen donor [N4] macrocyclic ligand, 1,3,7,9-tetraaza-2,8-dithia-4,10-dimethyl-6,12-diphenylcyclododeca-4,6,10,12-tetraene has been synthesized by using thiourea and benzoylacetone. Complexes of Mn(II), Co(II), Ni(II), and Cu(II) have been synthesized with this ligand and characterized by element chemical analysis, molar conductance, magnetic susceptibility, mass, 1H nuclear magnetic resonance, Fourier transform–infrared, electronic, and electron paramagnetic resonance spectral studies. The molar conductance measurements of Mn(II), Co(II), and Cu(II) complexes in dimethyformamide correspond to nonelectrolytes, whereas Ni(II) complex is a 1: 2 electrolyte. The complexes are high-spin except for Ni(II) which is diamagnetic. Octahedral geometry has been assigned for Mn(II) and Co(II) complexes, square planar for Ni(II) and tetragonal geometry for Cu(II). The ligand and its complexes were screened in vitro against two pathogenic fungi (Fusarium moniliformae and Rhizoctonia solani) and bacter...

Hyosmin (1) a new lignan has been isolated from the seeds of Hyoscyamus niger L. (Solanaceae), and its structure shown to be the 3-{[(2 R)-2-carbomethoxy-2-hydroxy]ethyl}benzoate ester of {(2 R,3 S,4 S)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-4-[(4-hydroxy-3-methoxyphenyl)methyl]tetrahydrofuran

1H, 13C NMR and X-ray crystallography have demonstrated the azomethine structure of the addition product obtained from N-amino-2,3-(9,10-dihydro-9,10-anthracenediyl)succinimide and diethyl acetylenedicarboxylate. The exo cyclic nitrogen exists in sp2-state and its lone pair lies in anti orientation while the diethyl succinate moiety has been demonstrated to be syn to the cage and orthogonal to the succinimide plane. On acetylation the product is transformed into N-acetyl derivative which exhibits restricted rotation about N–N bond and a preferred conformation with N-acetyl in syn-orientation.

1H, 13C NMR and X-ray crystallography have demonstrated the azomethine structure of the addition product obtained from N-amino-2,3-(9,10-dihydro-9,10-anthracenediyl)succinimide and diethyl acetylenedicarboxylate. The exo cyclic nitrogen exists in sp2-state and its lone pair lies in anti orientation while the diethyl succinate moiety has been demonstrated to be syn to the cage and orthogonal to the succinimide plane. On acetylation the product is transformed into N-acetyl derivative which exhibits restricted rotation about N–N bond and a preferred conformation with N-acetyl in syn-orientation.

In addition to the isolation and complete characterisation of a new lignan, hyoscyamal, three other compounds, balanophonin, pongamoside C and pongamoside D have been isolated from the seeds of Hyoscyamus niger. The structures of the compounds were settled on the basis of spectroscopic analysis. This is the first report on the isolation of these compounds from a solanaceous plant.

Chromium(III), manganese(II), iron(III), cobalt(II), nickel(II), copper(II), ruthenium(III), iridium(III), palladium(II) and platinum(II) complexes were synthesized with a 12-membered 1,4,7,10-tetraazadodeca-5,6,11,12-tetraene macrocylic ligand (L) and characterized by elemental analysis, molar conductance, magnetic susceptibility, IR, electronic, EPR and Mossbauer [Fe(III)] spectral studies. The molar conductance measurements of all the complexes in DMF solution correspond to non-electrolytic nature for M(L)Cl2 complexes [where M=Mn(II), Co(II), Ni(II), Cu(II)], 1:1 electrolytes for M'(L)Cl3 complexes [where M'=Cr(III), Fe(III), Ru(III) and Ir(III)] and 1:2 electrolytes for M''(L)Cl2 complexes [where M''=Pd(II) and Pt(II)]. Thus, the complexes may be formulated as [M(L)C1(2)], [M'(L)C1(2)]C1 and [M''(L)]C1(2), respectively [where L=ligand]. All complexes were of the high-spin type and found to have six-coordinate octahedral geometry except the Pd(II) and Pt(II) complexes which were four coordinate, square planar and diamagnetic.

Hyosmin (1) a new lignan has been isolated from the seeds of Hyoscyamus niger L. (Solanaceae), and its structure shown to be the 3-{[(2R)-2-carbomethoxy-2-hydroxy]ethyl}benzoate ester of {(2R,3S,4S)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-4-[(4-hydroxy-3-methoxyphenyl)methyl]tetrahydrofuran.