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241.
The present study was carried out to establish the hypolipidemic effect of a phyto-steroid compound isolated from the chloroform: methanol extract of fresh mature leaves of the plant Cestrum diurnum (Solanaceae: Solanales). Change in the haematological parameters was studied in normocholesterolemic albino rats after oral administration of single dose of isolated phytosteroid (2 mg/ day) up to 15 days and compared with control rats. Application of phytosteroid fraction resulted in a significant reduction in total plasma cholesterol and free cholesterol levels. The plasma triglyceride levels also decreased significantly. A sharp increase in the HDL cholesterol level and a significant decrease in the LDL and VLDL amount were also documented. Free fatty acid level was significantly low in treated rats. 相似文献
242.
Annals of Operations Research - Police patrol is an effective crime prevention tool and boosts public confidence in urban security. Many interesting decision making problems appear in route design,... 相似文献
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Gupta Goutam Kishore Mondal Monoj Kumar 《Journal of Thermal Analysis and Calorimetry》2019,137(4):1431-1441
Journal of Thermal Analysis and Calorimetry - The purpose of the study was to inspect the thermal degradation behavior of maize cob to find out its pyrolytic behavior for bioenergy generation.... 相似文献
244.
Mitrali Biswas Sanchaita Dey Abhishek Das Prof. Dr. Tapan Kanti Paine Dr. Sanjib Panda Prof. Dr. Goutam Kumar Lahiri 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(63):e202202088
The unexplored ‘actor’ behavior of redox-active bis(aldimine) congener, p-phenylene-bis(picoline)aldimine (L1), towards dioxygen activation and subsequent functionalization of its backbone was demonstrated on coordination with {Ru(acac)2} (acac= acetylacetonate). Reaction under aerobic condition led to the one-pot generation of dinuclear complexes with unperturbed L1, imino-carboxamido (L2−), and bis(carboxamido) (L32−)-bridged isovalent {RuII(μ-L1)RuII}, 1/ {RuIII(μ-L32−)RuIII}, 3 and mixed-valent {RuII(μ-L2−)RuIII}, 2 . Authentication of the complexes along with the redox non-innocence behavior of their bridge have been validated through structure, spectroelectrochemistry and DFT calculations. Kinetic and isotope labelling experiments together with DFT analyzed transition states justified the consideration of redox shuttling at metal/L1 interface for 3O2 activation despite of the closed shell configuration of 1 (S=0) to give carboxamido derived 2 / 3 . 相似文献
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Goutam Manna Riya Bose Dr. Narayan Pradhan 《Angewandte Chemie (International ed. in English)》2014,53(26):6743-6746
Au–Bi2S3 heteronanostructure photocatalysts were designed in which the coupling of a metal plasmon and a semiconductor exciton aids the absorption of solar light, enhances charge separation, and results in improved catalytic activity. Furthermore, these nanostructures show a unique pattern of structural combination, with Au nanoparticles positioned at the center of Bi2S3 nanorods. The chemistry of formation of these nanostructures, their epitaxy at the junction, and their photoconductance were studied, as well as their photoresponse properties. 相似文献
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Goutam Ghosh Huimin Yin Susan M.A. Monro Tariq Sainuddin Lloyd Lapoot Alexander Greer Sherri A. McFarland 《Photochemistry and photobiology》2020,96(2):349-357
Ru(II) complexes were synthesized with π-expanding (phenyl, fluorenyl, phenanthrenyl, naphthalen-1-yl, naphthalene-2-yl, anthryl and pyrenyl groups) attached at a 1H-imidazo[4,5-f][1,10]phenanthroline ligand and 4,4′-dimethyl-2,2′-bipyridine (4,4′-dmb) coligands. These Ru(II) complexes were characterized by 1D and 2D NMR, and mass spectroscopy, and studied for visible light and dark toxicity to human malignant melanoma SK-MEL-28 cells. In the SK-MEL-28 cells, the Ru(II) complexes are highly phototoxic (EC50 = 0.2–0.5 µm ) and have low dark toxicity (EC50 = 58–230 µm ). The highest phototherapeutic index (PI) of the series was found with the Ru(II) complex bearing the 2-(pyren-1-yl)-1H-imidazo[4,5-f][1,10]phenanthroline ligand. This high PI is in part attributed to the π-rich character added by the pyrenyl group, and a possible low-lying and longer-lived 3IL state due to equilibration with the 3MLCT state. While this pyrenyl Ru(II) complex possessed a relatively high quantum yield for singlet oxygen formation (Φ∆ = 0.84), contributions from type-I processes (oxygen radicals and radical ions) are competitive with the type-II (1O2) process based on effects of added sodium azide and solvent deuteration. 相似文献
250.
Isomeric Diruthenium Complexes Bridged by Deprotonated Indigo in cis and trans Configuration
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Madhumita Chatterjee Prabir Ghosh Katharina Beyer Dr. Alexa Paretzki Dr. Jan Fiedler Prof. Dr. Wolfgang Kaim Prof. Dr. Goutam Kumar Lahiri 《化学:亚洲杂志》2018,13(1):118-125
The doubly deprotonated form L2? of indigo=H2L can bind two [Ru(acac)2] complex fragments in the cis ( 1 ) and trans configuration ( 2 ), as evidenced from crystal structure analysis. While the latter type of N,O; N ’ ,O ’ coordination has been observed earlier, for example, with [Ru(bpy)2]2+, leading to two equivalent six‐membered ring chelates, the cis arrangement in 1 is observed here for the first time in a dinuclear complex, producing one five‐membered ring chelate with N,N ’ coordination and one seven‐membered chelate with O,O ’ coordination. The different structures of the isomers result in differing electrochemical and spectroelectrochemical (EPR, UV‐Vis‐NIR) responses for various accessible charge states 1 n and 2 n, n=–, 0, +, 2+. The associated electronic structures were analyzed by DFT (structures, spin density) and TD‐DFT calculations (electronic transitions), revealing mainly metal‐based reduction but largely indigo ligand‐based oxidation of both neutral precursors. 相似文献