Government College

About: Government College is a based out in . It is known for research contribution in the topics: Population & Ring (chemistry). The organization has 4481 authors who have published 5986 publications receiving 57398 citations.

Shape memory properties of epoxy/PPO-PEO-PPO triblock copolymer blends with tunable thermal transitions and mechanical characteristics

Abstract: In this paper, we report a simple method to prepare novel, transparent, hard-tough and hard-flexible shape memory and soft-flexible epoxy polymers based on poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) (PPO-PEO-PPO) triblock copolymer (TBCP) and diglycidyl ether of bisphenol-A (DGEBA)/4,4'-diaminodiphenylmethane (DDM) system. The PPO-PEO-PPO triblock copolymer was used to tailor crosslink density and flexibility in epoxy thermosets and thereby their glass transition temperature (Tg). The formed blends exhibit a phase separated morphology. The phase separation was initiated by immiscible PPO blocks via self-assembly. Three types of shape memory polymers, viz. stiff, intermediate and soft-flexible epoxy systems, with entirely different physical and mechanical properties were prepared only by adjusting the blend composition. All the blends were UV resistant, thermally and dimensionally stable and could be used for various outdoor applications. To the best of our knowledge, n...

A fruitful decade from 2005 to 2014 for anthraquinone patents

Abstract: Introduction: Anthraquinones are aromatic compounds whose structures are related to anthracene (parent structure: 9,10-dioxoanthracene) for which various methods for their synthesis have been developed. In the past decade (2005 – 2014), much work has been done regarding anthraquinone chemistry in order to discover new compounds related to this scaffold as anticancer, antibacterial, antidiabetic, antiviral, anti-HCV, antifibrotic, fungicidal and anti-inflammatory agents.Areas covered: This review covers the patents on therapeutic activities of anthraquinones and their derivatives in the years between 2005 and 2014. A large portion of the therapeutic applications that were reported in international patents will be presented and discussed. Although a large number of patents have been registered over the last decade, this review is focused on important patents related to cancer, inflammation, infectious diseases, diabetic conditions and hepatitis C.Expert opinion: The tricyclic planar ring system of anthraqui...

Nanoscale petrographic and geochemical insights on the origin of the Palaeoproterozoic stromatolitic phosphorites from Aravalli Supergroup, India

Abstract: Stromatolites composed of apatite occur in post-Lomagundi-Jatuli successions (late Palaeoproterozoic) and suggest the emergence of novel types of biomineralization at that time. The microscopic and nanoscopic petrology of organic matter in stromatolitic phosphorites might provide insights into the suite of diagenetic processes that formed these types of stromatolites. Correlated geochemical micro-analyses of the organic matter could also yield molecular, elemental and isotopic compositions and thus insights into the role of specific micro-organisms among these communities. Here, we report on the occurrence of nanoscopic disseminated organic matter in the Palaeoproterozoic stromatolitic phosphorite from the Aravalli Supergroup of north-west India. Organic petrography by micro-Raman and Transmission Electron Microscopy demonstrates syngeneity of the organic matter. Total organic carbon contents of these stromatolitic phosphorite columns are between 0.05 and 3.0 wt% and have a large range of δ(13) Corg values with an average of -18.5‰ (1σ = 4.5‰). δ(15) N values of decarbonated rock powders are between -1.2 and +2.7‰. These isotopic compositions point to the important role of biological N2 -fixation and CO2 -fixation by the pentose phosphate pathway consistent with a population of cyanobacteria. Microscopic spheroidal grains of apatite (MSGA) occur in association with calcite microspar in microbial mats from stromatolite columns and with chert in the core of diagenetic apatite rosettes. Organic matter extracted from the stromatolitic phosphorites contains a range of molecular functional group (e.g. carboxylic acid, alcohol, and aliphatic hydrocarbons) as well as nitrile and nitro groups as determined from C- and N-XANES spectra. The presence of organic nitrogen was independently confirmed by a CN(-) peak detected by ToF-SIMS. Nanoscale petrography and geochemistry allow for a refinement of the formation model for the accretion and phototrophic growth of stromatolites. The original microbial biomass is inferred to have been dominated by cyanobacteria, which might be an important contributor of organic matter in shallow-marine phosphorites.