scispace - formally typeset
Search or ask a question
Author

Amitava Ghosh

Bio: Amitava Ghosh is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Grinding & Machining. The author has an hindex of 23, co-authored 87 publications receiving 1507 citations. Previous affiliations of Amitava Ghosh include Indian Institute of Technology Guwahati & Indian Institute of Technology Kharagpur.
Topics: Grinding, Machining, Diamond, Lubrication, Alloy


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, an investigation has been undertaken to study the compatibility of cutting materials in dry machining of aluminium and Al-Si alloys, and the results of turning test, SEM pictures and chip morphology investigation of the cutting tool after machining clearly reveal the inefficiency of TiC, TiN, TiB2, Al2O3, and AlON.
Abstract: An investigation has been undertaken to study the compatibility of cutting materials in dry machining of aluminium and Al–Si alloys. Mono or multilayer coated carbide tools with a top coating of TiC, TiN, TiAlN, Al2O3, TiB2, MoS2 etc. on WC–Co inserts already made a major breakthrough in dry machining of ferrous materials. But in contrast dry machining of aluminium and Al-alloys is a great challenge. But wide application of aluminium different parts has increased the need to find out the correct cutting tool. Experimental results of turning test, SEM pictures and chip morphology investigation of the cutting tool after machining clearly reveals the inefficiency of TiC, TiN, TiB2, Al2O3, and AlON in dry machining of aluminium. This is because of the formation of very large amount of metal built-up in both rake and flank surface leading to high magnitude of cutting forces and high roughness of the work-piece during machining. The natural diamond and polycrystalline diamond (PCD) can be used as a cutting tool, when the required shape is attached on the edge/tip for machining non-ferrous materials. But both of them are limited for finishing cut because of high cost. So CVD diamond coated tool is a better option to machine these materials. CVD diamond coated tool was free from built-up edge formation leading to clean cut, low magnitude of cutting forces and improved surface finish of the work-piece. However, performances of the diamond tool depend mainly on adhesion of the diamond coating with the carbide substrate.

110 citations

Journal ArticleDOI
TL;DR: The aim of the present study is to improve the solubility and dissolution rate and in turn the hepatoprotective activity of the drug, by formulating its inclusion complex with beta (β)-cyclodextrin, using different methods.

96 citations

01 Jan 2011
TL;DR: The new generation of orally disintegrating tablet (ODT) technologies is no longer limited by dosage strength, bitter active pharmaceutical ingredients (APIs), and narrow therapeutic applications.
Abstract: Advancements in oral delivery of active ingredients include a number of technologies, many of which may be classified as oral disintegrating tablets (ODTs). A number of companies have marketed products using various nomenclatures including ODT as well as their own trademarked names. The new generation of orally disintegrating tablet (ODT) technologies is no longer limited by dosage strength, bitter active pharmaceutical ingredients (APIs), and narrow therapeutic applications. Today’s emerging technologies can produce robust, versatile tablets with exceptional taste masking and controlled release, broadening the applications of this dosage form. Over the last decade, ODTs have grown steadily in demand and importance as a convenient, potentially safer alternative to conventional tablets and capsules. ODTs are solid dosage forms that disintegrate in the mouth in less than 60 seconds, and are thus swallowed without the need for water. Since their introduction to the market in the 1980s, ODTs have become one of the fastest‐growing segments of the oral drug delivery industry, and their product pipeline is rapidly expanding. They are particularly beneficial to people who have difficulty taking conventional solid dosage forms, including children, the elderly, patients who have swallowing difficulties, the mentally ill, and the disabled. This review depicts the various formulation techniques, ingredients used, and overview of patented formulations.

84 citations

Journal ArticleDOI
TL;DR: In this paper, an investigation of the grindability of Titanium alloy Ti-6Al-4V with monolayered brazed type superabrasive grinding wheels is presented.
Abstract: This paper deals with an investigation of the grindability of Titanium alloy Ti–6Al–4V with monolayered brazed type superabrasive grinding wheels. The experiments, conducted under different grinding environments, showed the performance of the grinding fluids based on an evaluation of grinding forces, chip formation and tool condition. It could be found that conventional grinding fluids like oil or alkaline soap are preferable compared to dry or cryogenic conditions or with MoS 2 coated wheels.

81 citations

Journal ArticleDOI
TL;DR: This review will provide an insight into previous studies on microemulsions for ocular delivery of drugs using various nonionic surfactants, cosurfactants, and associated irritation potential on the ocular surface.
Abstract: Delivery of drugs into eyes using conventional drug delivery systems, such as solutions, is a considerable challenge to the treatment of ocular diseases. Drug loss from the ocular surface by lachrymal fluid secretion, lachrymal fluid-eye barriers, and blood-ocular barriers are main obstacles. A number of ophthalmic drug delivery carriers have been made to improve the bioavailability and to prolong the residence time of drugs applied topically onto the eye. The potential use of microemulsions as an ocular drug delivery carrier offers several favorable pharmaceutical and biopharmaceutical properties such as their excellent thermodynamic stability, phase transition to liquid-crystal state, very low surface tension, and small droplet size, which may result in improved ocular drug retention, extended duration of action, high ocular absorption, and permeation of loaded drugs. Further, both lipophilic and hydrophilic characteristics are present in microemulsions, so that the loaded drugs can diffuse passively as well get significantly partitioned in the variable lipophilic-hydrophilic corneal barrier. This review will provide an insight into previous studies on microemulsions for ocular delivery of drugs using various nonionic surfactants, cosurfactants, and associated irritation potential on the ocular surface. The reported in vivo experiments have shown a delayed effect of drug incorporated in microemulsion and an increase in the corneal permeation of the drug.

67 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: The description of energy transfer, in particular multichromophoric antenna structures, is shown to vary depending on the spatial and energetic landscape, which dictates the relative coupling strength between constituent pigment molecules.
Abstract: The process of photosynthesis is initiated by the capture of sunlight by a network of light-absorbing molecules (chromophores), which are also responsible for the subsequent funneling of the excitation energy to the reaction centers. Through evolution, genetic drift, and speciation, photosynthetic organisms have discovered many solutions for light harvesting. In this review, we describe the underlying photophysical principles by which this energy is absorbed, as well as the mechanisms of electronic excitation energy transfer (EET). First, optical properties of the individual pigment chromophores present in light-harvesting antenna complexes are introduced, and then we examine the collective behavior of pigment−pigment and pigment−protein interactions. The description of energy transfer, in particular multichromophoric antenna structures, is shown to vary depending on the spatial and energetic landscape, which dictates the relative coupling strength between constituent pigment molecules. In the latter half...

714 citations

Journal ArticleDOI
TL;DR: The biopolymer aerogel field today is driven forward by empirical materials discovery at the laboratory scale, but requires a firmer theoretical basis and pilot studies to close the gap to market.
Abstract: Biopolymer aerogels were among the first aerogels produced, but only in the last decade has research on biopolymer and biopolymer-composite aerogels become popular, motivated by sustainability arguments, their unique and tunable properties, and ease of functionalization. Biopolymer aerogels and open-cell foams have great potential for classical aerogel applications such as thermal insulation, as well as emerging applications in filtration, oil-water separation, CO2 capture, catalysis, and medicine. The biopolymer aerogel field today is driven forward by empirical materials discovery at the laboratory scale, but requires a firmer theoretical basis and pilot studies to close the gap to market. This Review includes a database with over 3800 biopolymer aerogel properties, evaluates the state of the biopolymer aerogel field, and critically discusses the scientific, technological, and commercial barriers to the commercialization of these exciting materials.

397 citations