Design and characterization of randomly speckled spheres

We use the "particle lithography" technique to fabricate randomly speckled spheres. Parts of positively charged 3.3 microm polystyrene microspheres were masked off with negatively charged 0.9 microm silica particles, and the remaining portion was covered with negatively charged 60 nm polystyrene nanoparticles. The masking particles were then removed to leave speckles on the larger core particle. Images from electron microscope and confocal microscope show that the diameter of the circular speckles is predictable and reliable, following an estimate from simple geometry, and that the number of speckles formed on a particle can be altered by changing the concentration of silica particle masks. The process described in this paper can be adapted to a wide variety of materials, opening the door for applications where size-controlled patches of one chemistry can appear on core particles of another chemistry and where the precise placement of patches is of little importance.     

An efficient, one-pot synthesis of trithiocarbonates from alcoholic tosylates using the Cs2CO3/CS2 system

A single-step novel protocol for the preparation of symmetrical trithiocarbonates from a corresponding variety of primary, secondary, and tertiary alcoholic tosylates using the Cs₂CO₃/CS₂ system, was developed. This protocol is mild and more efficient than the reported methods.     

Triton-B catalyzed,efficient one-pot synthesis of dithiocarbazates

A quick and efficient, one-pot synthesis of dithiocarbazates was accomplished in high yields by the reaction of various primary, secondary, and tert. alkyl halides with a variety of substituted hydrazines using the benzyl-trimethylammonium hydroxide (Triton-B)/CS₂ system. The reaction conditions are mild with simpler work-up procedures than the reported methods. Correspondence: Devdutt Chaturvedi, Medicinal and Process Chemistry Division, Central Drug Research Institute, Lucknow-226001, U.P., India.     

Synthesis and characterization of oxygen depleted tert-amine calix[4]arene ligands and study the effect on sigma non-opioid intracellular protein receptor

Structural Chemistry - This study focuses on the biological prospects of oxygen-depleted calix[4]arene ligands on a protein target. Because of their extensive medical relevance, the oxygen-depleted...     

Applications of nano-catalyst in new era

In the era of nanoscience where all the devices and technologies are going to smaller and smaller in size with improved properties; catalysis is an important field of application. In this review article we are trying to summarize data reported in literature for application of nano sized catalyst in our daily life which are useful for human beings. Improvement in catalytic properties due size of catalyst reduced to nano scale is discussed here. Introductive points regarding nanoscience; their functional approaches; current research are also here.Main applications of nanocatalysts in water purification; fuel cell; energy storage; in composite solid rocket propellants; bio diesel production; in medicine; in dye; application of carbon nano tubes and several other point of application are discussed here in detail.     

Volume-of-fluid algorithm with different modified dynamic material ordering methods and their comparisons

Volume-of-fluid (VOF) interface reconstruction methods are used to define material interfaces to separate different materials in a mixed cell. These material interfaces are then used to evaluate transport flux at each cell edges in multi-material hydrodynamic calculations. Most of the VOF interface reconstruction methods and volume transport schemes rely on an accurate material order unique to each computational cell. Similarly, to achieve overshoot-free volume fractions, a non-intersecting interface reconstruction procedure has to be performed with the help of a ‘material-order list’ determined prior to interface reconstruction. It is, however, the least explored area of VOF technique especially for ‘onion-skin’ or ‘layered’ model. Also, important technical details how to prevent intersection among different material interfaces are missing in many literature. Here, we present an efficient VOF interface tracking algorithm along with modified ‘material order’ methods and different interface reconstruction methods. The relative accuracy of different methods are evaluated for sample problems. Finally, a convergence study with respect to mesh-size is performed.     

An efficient,one-pot synthesis of trithiocarbonates from alcoholic tosylates using the Cs<Subscript>2</Subscript>CO<Subscript>3</Subscript>/CS<Subscript>2</Subscript> system

A single-step novel protocol for the preparation of symmetrical trithiocarbonates from a corresponding variety of primary, secondary, and tertiary alcoholic tosylates using the Cs₂CO₃/CS₂ system, was developed. This protocol is mild and more efficient than the reported methods. Correspondence: Devdutt Chaturvedi, Bio-Organic Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu-Tawi-18000, J&K, India.     

Triton-B catalyzed, efficient one-pot synthesis of carbazates

A quick and efficient, one-pot synthesis of carbazates was accomplished in high yields by the reaction of various primary, secondary, and tertiary alkyl halides with a variety of substituted hydrazines using the benzyltrimethylammonium hydroxide (Triton-B)/CO₂ system. The reaction conditions are mild with simpler work-up procedures than the reported methods. Correspondence: Devdutt Chaturvedi, Bio-Organic Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu-Tawi 18000, J&K, India.