Wetting and phase separation at surfaces

We study the problem ofsurfacedirected spinodal decomposition, viz., the dynamical interplay of wetting and phase separation at surfaces. In particular, we focus on the kinetics of wetting-layer growth in a semi-infinite geometry for arbitrary surface potentials and mixture compositions. We also present representative results for phase separation in confined geometries, e.g., cylindrical pores, thin films, etc.     

An experimental investigation on pool boiling heat transfer enhancement using Cu-Al2O3 nano-composite coating

Pool boiling heat transfer performances of Cu-Al₂O₃-coated copper surfaces have been studied experimentally for its potential use in heat transfer applications. In the present study, a two-step electrochemical deposition method is examined. This method provides an easy control on surface properties such as porosity and coating thickness. The deposition method is studied carefully and responsible surface morphology parameters are reported. After performing the pool boiling experiments on coated surfaces with DI water, the maximum critical heat flux of 1800 kW/m² and heat transfer coefficient of 193 kW/m² K, which are 68% and 260% higher than that of bare surface, respectively.     

Periodic orbits around the collinear libration points in the restricted three body problem when the smaller primary is a triaxial rigid body and bigger primary is a source of radiation pressure

Periodic orbits belonging to the stromgren families A, B and C around the collinear libration points in the restricted three body problem have been studied when the smaller primary is a triaxial rigid body and more massive body is a source of radiation pressure. These families are determined in three different cases: (i) classical case, (ii) when bigger primary is a source of radiation pressure, (iii) when smaller primary is a triaxial rigid body and bigger primary is a source of radiation pressure. The Liapunov stability of each periodic solution has also been examined.      

An efficient, rapid, and regioselective bromination of anilines and phenols with 1-butyl-3-methylpyridinium tribromide as a new reagent/solvent under mild conditions

1-Butyl-3-methylpyridinium tribromide, [BMPy]Br₃ proves to be a highly efficient, regioselective reagent/solvent for nuclear bromination of various anilines and phenols. The synthesis and characterization of the room temperature ionic liquid [BMPy]Br₃ (2) is described. The bromination was carried out in the absence of organic solvents and in most cases the only extraction solvent needed was water. The spent 1-butyl-3-methylpyridinium bromide (1) was easily recycled.     

Direct synthesis of esters and amides from unprotected hydroxyaromatic and -aliphatic carboxylic acids

A facile method for the activation of hydroxy-substituted carboxylic acids using benzotriazole chemistry without prior protection of the hydroxy substituents is presented. The N-acylbenzotriazole intermediates 2a-g, 6a-d, and 9a-c have been used for high-yielding synthesis of both aliphatic (3a-l) and aromatic (7a-h, 10a-f) hydroxy carboxamides. High yields of aromatic hydroxy esters 12a-h and 13a-i were obtained using either neat alcohols in neutral microwave conditions or nucleophilic alkoxides and the intermediate N-(arylacyl)benzotriazoles. Moderate yields were obtained in the case of aliphatic hydroxy esters 11a,b and thiolesters 11e-g from the intermediates 2a-c.     

Dysobinin,a tetranortriterpenoid

The planar furan ring in the title compound (6β‐acetoxy­aza­dirone, C₃₀H₃₈O₆) is twisted with respect to the steroid D ring. The crystal structure is stabilized by C—H?O hydrogen bonds and van der Waals interactions.     

A new form of discotic metallomesogens: the synthesis of metal-bridged triphenylene discotic dimers

Discotic metallomesogens are becoming increasingly important due to their electronic and optoelectronic properties. Preliminary results on the synthesis and characterization of a new form of discotic metallomesogens in which a Hg atom is covalently linked with two substituted triphenylene moieties are presented.     

Effect of two-step electrodeposited Cu–TiO2 nanocomposite coating on pool boiling heat transfer performance

Journal of Thermal Analysis and Calorimetry - In order to decrease the energy consumptions in energy conversion devices, boiling heat transfer augmentation is one of the important research...     

Stability-Indicating HPTLC Method for the Determination of Atorvastatin and Ezetimibe: Application to Pharmaceutical Dosage Forms

JPC – Journal of Planar Chromatography – Modern TLC -     

An efficient green protocol for the synthesis of coumarin fused highly decorated indenodihydropyridyl and dihydropyridyl derivatives

A simple, convenient, environmentally benign, and mild synthetic method has been established to afford highly decorated indenodihydropyridine and dihydropyridine derivatives employing a green solvent ethyl-l-lactate and an organo-catalyst (±)lactic acid. A wide range of functional groups were tolerated in the developed protocol. The target molecules were obtained in moderate to good yields applying the current method.