1,676 research outputs found

    Alkoxyallene‐Based LANCA Three‐Component Synthesis of 1,2‐Diketones, Quinoxalines, and Unique Isoindenone Dimers and a Computational Study of the Isoindenone Dimerization

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    A series of β‐alkoxy‐β‐ketoenamides was prepared by the well‐established LANCA three‐component reaction of lithiated 1‐(2‐trimethylsilylethoxy)‐substituted allenes, nitriles, and α,β‐unsaturated carboxylic acids. The α‐tert‐butyl‐substituted compounds were smoothly converted into the expected 1,2‐diketones by treatment with trifluoroacetic acid. A subsequent condensation of the 1,2‐diketones with o‐phenylenediamine provided the desired highly substituted quinoxalines in good overall yield. Surprisingly, the α‐phenyl‐substituted β‐alkoxy‐β‐ketoenamides investigated afford not only the expected 1,2‐diketones, but also pentacyclic compounds with an anti‐tricyclo[4.2.1.12,5]deca‐3,7‐diene‐9,10‐dione core. These interesting products are very likely the result of an isoindenone dimerization which was mechanistically studied with the support of DFT calculations. Under the strongly acidic reaction conditions, a stepwise reaction is likely leading to a protonated isoindenone as reactive intermediate. It may first form a van der Waals complex with a neutral isoindenone before the two regio‐ and diastereoselective ring forming steps occur. Interestingly, two neutral or two protonated isoindenones are also predicted to dimerize giving the observed pentacyclic product

    Millimeterwave CW Doppler Radar for Vibration Remote Sensing

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    Development of a Collision Avoidance System at Infrared Wavelength

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    Productivity, Energy Use Efficiency and Economics of Organic Scented Rice Cultivation in Sub-Humid Agroecosystem

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    The increasing demand for organic cereals especially indigenous scented rice varieties in the recent years has peaked farmers’ interest towards its organic production. However, the threat of crop loss under organic cultivation has been holding back large scale initiatives. Inhana Rational Farming (IRF) Technology has come up as a promising organic package of practice towards mitigating this drawback of organic production that too at an affordable economics. The present study was conducted to generate scientific information regarding organic scented rice cultivation (Oryza sativa var. ‘Gobindobhog’) utilizing this organic POP in terms of productivity, energy use efficiency and economics. The yield of scented rice cultivated using organic POP was found to be 18% higher than the conventionally grown ones. In terms of energy use efficiency as well, organic POP was calculated to be more efficient signifying the role of organic practice in sustainable agriculture. Net profitability of organic paddy increased up to 17% with a minimum premium price of 25%. This increased higher income opportunity from same unit of land was an added benefit apart from improved soil quality in general; under organic management

    An Innovative Approach towards Organic Management of Late Blight in Potato under Inhana Rational Farming Technology

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    Successful disease combat of crop can ensure healthy return for the farmers. However, limitation in the conventional disease management approach, especially in case of late blight of potato was the background for the present study that aimed at bringing forth an alternative pathway for effective disease management. Integrated farming under Inhana rational farming technology (IRF) was adopted as an alternate protocol. The approach works on the philosophy of the Trophobiosis theory that advocates pest/disease management through plant physiology management. The study was done in two major potato growing zones of West Bengal taking two major potato varieties i.e., Kufri Jyoti and Kufri Chandramukhi. Late blight incidence varied from 2.82 to 7.91% in the IRF integrated farming plots whereas it was relatively higher varying between 49.44 and 66.67% in case of plots receiving conventional treatment. The finding remained consistent irrespective of the study area and potato variety. Ineffective disease management influenced the net loss of 2400 kg potato ha-1 under conventional farming. Percent disease index (PDI) was significantly high in case of conventional farmers’ practice (11.37 to 32.81). However, lower values (PDI varies 1.45 to 2.59) under IRF integrated farming showed the effectiveness of its disease management schedule. Efficient disease management under IRF technology might have been brought about through a focused approach towards activation of plant physiology in order to re-instate plants’ structural and biochemical defense mechanisms. The findings encourage the possibility of economically sustainable potato production under the changing climatic patterns

    Phase evolution of EBPVD coated ceria-zirconia nanostructure and its impact on high temperature oxidation of AISI 304.

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    The present work focusses on the effect of nanocrystalline xCeO2 – (1-x)ZrO2 (x = 1, 0.75, 0.5, 0.25 and 0 in wt% abbreviated as C100, C75Z25, C50Z50, C25Z75 and Z100) coated by electron beam physical vapour deposition (EBPVD) on AISI 304 and its implication on the high-temperature oxidation protection. The oxidation kinetics indicate that the samples C100, C75Z25 and C50Z50 show 3–4 orders better oxidation protection than uncoated AISI 304. Coating morphology and composition play an important role in developing superior nanostructures against high temperature oxidation. The development of ceria-zirconia coating helps in the realization of structural materials for elevated temperature application
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