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Tyagi, Ajay Kumar
- Viable Feedstock Options and Technological Challenges for Ethanol Production in India
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PDF Views:82
Authors
Affiliations
1 Shriram Institute for Industrial Research, 19, University Road, Delhi 110 007, IN
1 Shriram Institute for Industrial Research, 19, University Road, Delhi 110 007, IN
Source
Current Science, Vol 111, No 5 (2016), Pagination: 815-822Abstract
Though improvements in processing and technology are important, the fluctuating price of inputs such as molasses, corn, sugar beet, sugarcane, sweet sorghum, starch, etc. and their seasonal availability play an important role in ethanol industry. As a matter of fact, the ethanol industry based on conventional resources has reached its saturation point. Technologies for ethanol production from lignocellulosics are being developed by scientists world over with the objective of exploiting the potential of a resource, which is otherwise considered a waste, to generate energy. The focus has been to produce ethanol in a cost-effective manner, besides aiming to find use of its by-products as food supplements for cattles, etc. Recent developments like adoption of technologies such as dry grind fractionation, which is now commercially viable, would reduce the cost of milling; wet milling being cost-intensive and dry milling requiring smaller plants.Keywords
Ethanol, Feedstock, Lignocellulosics, Molasses, Sugarcane.Full Text
- Controlled Hydrolytic Degradation of Polyglycolide–Caprolactone-Based Bioabsorbable Copolymer
Abstract Views :229 |
PDF Views:75
Authors
Affiliations
1 Material Science Division, Shriram Institute for Industrial Research, 19-University Road, Delhi 110 007, IN
1 Material Science Division, Shriram Institute for Industrial Research, 19-University Road, Delhi 110 007, IN
Source
Current Science, Vol 113, No 07 (2017), Pagination: 1354-1360Abstract
Polyglycolide–caprolactone (PGCL)-based copolymer was synthesized from glycolide and caprolactone by ring opening polymerization in the presence of stannous octoate catalyst and diethylene glycol initiator. The effects of prepolymerization time, monomer ratio, monomer-to-catalyst and monomer-to-initiator ratios on per cent weight conversion were optimized. The end-capped copolymer was synthesized to make absorbable sutures having controlled bioabsorbability at different pH levels. It was observed that endcapped absorbable copolymer was more stable at pH 10.0 compared to uncapped absorbable material. End-capped copolymer also retained higher tensile strength compared to uncapped copolymer after 21 days. This phenomenon of controlled hydrolytic degradation of PGCL-based bioabsorbable polymer having terminal group end-capping can be attributed to less availability of hydrophilic end groups facilitating hydrolytic degradation of polymers.Keywords
Biocompatibility, Bioabsorbable Copolymer, Hydrolytic Degradation, Polyglycolide–Caprolactone, Suture.Full Text
References
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- Fourth-Generation Refrigerant:HFO 1234yf
Abstract Views :227 |
PDF Views:73
Authors
Affiliations
1 Material Science Division, Shriram Institute for Industrial Research, 19, University Road, Delhi 110 007, IN
1 Material Science Division, Shriram Institute for Industrial Research, 19, University Road, Delhi 110 007, IN
Source
Current Science, Vol 115, No 8 (2018), Pagination: 1497-1503Abstract
Refrigeration is a process to transfer heat from the objects for cooling and freezing for maintaining the temperature of surroundings for preservation purposes and comfort. Refrigerants are the materials to use in air-conditioning and refrigeration system. This article describes the developments and history of the first-, second-, third- and fourth-generation refrigerants. Moreover, the focus is on a fourth-generation refrigerant, viz. HFO-1234yf having zero ozone depletion potential and very low global warming potential. Synthesis procedure, chemistry, applications and consumption norms of HFO-1234yf are explained.Keywords
Air-Conditioning and Refrigeration, Fourth-Generation Refrigerants, Global Warming Potential, Ozone Depleting Potential.Full Text
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