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81.
Singha Mousumi Pal Sangita Chowdhury Sujit Hareendran K. N. Sahu M. L. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):795-803
Journal of Radioanalytical and Nuclear Chemistry - The sorption capacity of an in–house synthesized novel resin Polyhydraxamic acid(PHA) towards Cu(II), Sr(II), Gd(III), U(VI) ions was... 相似文献
82.
Narayan D. Chaurasiya Jacob Midiwo Pankaj Pandey Regina N. Bwire Robert J. Doerksen Ilias Muhammad Babu L. Tekwani 《Molecules (Basel, Switzerland)》2020,25(22)
A set of structurally related O-methylated flavonoid natural products isolated from Senecio roseiflorus (1), Polygonum senegalense (2 and 3), Bhaphia macrocalyx (4), Gardenia ternifolia (5), and Psiadia punctulata (6) plant species were characterized for their interaction with human monoamine oxidases (MAO-A and -B) in vitro. Compounds 1, 2, and 5 showed selective inhibition of MAO-A, while 4 and 6 showed selective inhibition of MAO-B. Compound 3 showed ~2-fold selectivity towards inhibition of MAO-A. Binding of compounds 1–3 and 5 with MAO-A, and compounds 3 and 6 with MAO-B was reversible and not time-independent. The analysis of enzyme-inhibition kinetics suggested a reversible-competitive mechanism for inhibition of MAO-A by 1 and 3, while a partially-reversible mixed-type inhibition by 5. Similarly, enzyme inhibition-kinetics analysis with compounds 3, 4, and 6, suggested a competitive reversible inhibition of MAO-B. The molecular docking study suggested that 1 selectively interacts with the active-site of human MAO-A near N5 of FAD. The calculated binding free energies of the O-methylated flavonoids (1 and 4–6) and chalcones (2 and 3) to MAO-A matched closely with the trend in the experimental IC50′s. Analysis of the binding free-energies suggested better interaction of 4 and 6 with MAO-B than with MAO-A. The natural O-methylated flavonoid (1) with highly potent inhibition (IC50 33 nM; Ki 37.9 nM) and >292 fold selectivity against human MAO-A (vs. MAO-B) provides a new drug lead for the treatment of neurological disorders. 相似文献
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84.
Laxman Singh Ravikant Sharma Narayan Singh Atendra Kumar Dev K Mahato Youngil Lee Mikhael Bechelany KD Mandal 《Progress in Crystal Growth and Characterization of Materials》2021,67(4):100542
This review paper covers the low temperature wet growth of nano-engineered particles of ZnO-based mixed metal oxides, their growth mechanism, and characterization using X-ray diffraction, SEM, TEM and IR, UV–visible, and XPS spectral techniques. Main focus of this article is centered on low temperature semi-wet methods of synthesis that are suitable for large scale production of zinc oxide-based systems mixed with iron oxide, copper oxide, nickel oxide and cobalt oxide. These mixed metal oxides have broad industrial applications as catalyst, semiconductors, adsorbents, superconductors, electro-ceramics, and antifungal agents in addition to extensive applications in medicines. This paper discusses the low-cost and environment friendly synthesis of these mixed metal oxides, measurement of properties and applicability of these materials systems. 相似文献
85.
N-Benzyl-2-naphthohydroxamic acid extracts vanadium(V) selectively and quantitatively into chloroform from 2-8.5M hydrochloric acid in the presence of Mo(VI), Zr(IV) and Ce(IV). The extraction takes place quickly and gives a stable reddish-violet extract which shows an absorption maximum at 505 nm with molar absorptivity of (5.34 +/- 0.05) x 10(3) 1.mole(-1).cm(-1). The optimum range for the determination is 2.2-7.4 ppm of vanadium(V) in the final solution. The method has been used for the determination of vanadium in steels. 相似文献
86.
The basic principle for the production of polarised thermal neutrons is discussed and the choice of various crystal monochromators
surveyed. Brief mention of broad-spectrum polarisers is made. The application of polarised neutrons to the study of magnetisation
density distributions in magnetic crystals, the dynamic concept of polarisation, principle and use of polarisation analysis,
the neutron spin-echo technique are discussed. 相似文献
87.
Har Mohindra Chawla Satya Narayan Sahu Rahul Shrivastava Satish Kumar 《Tetrahedron letters》2012,53(17):2244-2247
A series of calix[4]arene based ditopic receptors possessing bipyridyl and hydrazone units have been synthesized and evaluated for ionic recognition. It has been observed that the synthesized derivatives function as allosteric receptors for simultaneous recognition of Co2+and F? ions through non-covalent interactions. Significant bathochromic shifts in the UV–visible spectrum with a profound colour change promise their use to engineer novel applications. 相似文献
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90.
Harihara Padhy Jen‐Hsien Huang Duryodhan Sahu Dhananjaya Patra Dhananjay Kekuda Chih‐Wei Chu Hong‐Cheu Lin 《Journal of polymer science. Part A, Polymer chemistry》2010,48(21):4823-4834
A series of soluble donor‐acceptor conjugated polymers comprising of phenothiazine donor and various benzodiazole acceptors (i.e., benzothiadiazole, benzoselenodiazole, and benzoxadiazole) sandwiched between hexyl‐thiophene linkers were designed, synthesized, and used for the fabrication of polymer solar cells (PSC). The effects of the benzodiazole acceptors on the thermal, optical, electrochemical, and photovoltaic properties of these low‐bandgap (LBG) polymers were investigated. These LBG polymers possessed large molecular weight (Mn) in the range of 3.85?5.13 × 104 with high thermal decomposition temperatures, which demonstrated broad absorption in the region of 300?750 nm with optical bandgaps of 1.80?1.93 eV. Both the HOMO energy level (?5.38 to ?5.47 eV) and LUMO energy level (?3.47 to ?3.60 eV) of the LBG polymers were within the desirable range of ideal energy level. Under 100 mW/cm2 of AM 1.5 white‐light illumination, bulk heterojunction PSC devices containing an active layer of electron donor polymers mixed with electron acceptor [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) or [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) in different weight ratios were investigated. The best performance of the PSC device was obtained by using polymer PP6DHTBT as an electron donor and PC71BM as an acceptor in the weight ratio of 1:4, and a power conversion efficiency value of 1.20%, an open‐circuit voltage (Voc) value of 0.75 V, a short‐circuit current (Jsc) value of 4.60 mA/cm2, and a fill factor (FF) value of 35.0% were achieved. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献