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71.
Journal of Fluorescence - We constructed a novel-binding site for metal ion detection using a fused tetrazole ring conjugated with aminopyrene (R). The designed structure of the molecule was...  相似文献   
72.
For NiO nanorods of 5 nm diameter prepared by sol-gel technique, variations of the magnetization M with temperature T (5-370 K) and magnetic field H up to 55 kOe are reported. Also, temperature variations of the EMR (electron magnetic resonance) parameters (intensity I0, linewidth ΔH and resonance field Hr) of an observed line due to uncompensated spins are followed for The M vs. H and T variations yield a blocking above which the data fits modified Langevin function with magnetic moment μp?1240 μB/particle. For the EMR line, I0 decreases rapidly for T<TB, and the line broadens and shifts to lower H with lowering T, following the lineshift δHr=(ΔH)n with n?2.8. This is close to the value of n=3 expected for randomly oriented particles.  相似文献   
73.
Research on Chemical Intermediates - Herbacetin (HBN) is an antiviral agent of H1N1 influenza virus which was reported to inhibit H1N1 neuraminidase (NA) enzyme with IC50 value of...  相似文献   
74.
Synthesis and structural characterization of distorted pentagonal bipyramidal Co(II), pseudo-octahedral Ni(II) and Cu(II) complexes of the type [ML(NO3)2], {L = N-(2-pyridylethyl)pyridine-2-methylketimine} are reported. Characterization includes elemental analysis, spectral, magnetism, and X-ray crystallographic studies. In case of cobalt (1) both the nitrates coordinate in bidentate fashion resulting overall distorted pentagonal bipyramidal geometry. In nickel (2) and copper (3) complexes, bivalent metal ion is coordinated by the three nitrogen atoms of the tridentate L with two pyridine-N occupying trans positions and amongst the two nitrates one coordinates in a bidentate fashion while other adopts a monodentate fashion. All the complexes exhibit d–d transitions in the visible region. Complex 1 is high-spin in nature and the X-band EPR spectra of 1, and 3 at room temperature and 77 K are reported.  相似文献   
75.
Changes in antioxidant potentials and indole alkaloid, ajmalicine, production were studied in Catharanthus roseus (L.) G. Don. plants under treatment with gibberellic acid (GA(3)). The GA(3) treatments were given in two ways, foliar spray and soil drenching methods on 30, 45, 60 and 75 days after planting (DAP). The plants were uprooted randomly on 90 DAP and separated into root, stem and leaves and used for analyses. The antioxidant potential was studied in terms of non-enzymatc antioxidant molecules like ascorbic acid (AA), alpha-tocopherol (alpha-toc) and reduced glutathione (GSH) and activities of antioxidant enzyme, viz., superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT). The alkaloid ajmalicine was extracted and estimated from roots of both control and treated plants. It was found that, GA(3) has a profound effect upon the antioxidant potentials and it caused a significant enhancement in the production of ajmalicine when compared to untreated control as well as foliar-sprayed plants. There was no significant enhancement in GSH and ajmalicine content under GA(3) foliar spray in C. roseus. These preliminary results suggest that, the application of GA(3) may be a useful tool to increase the antioxidant potential and alkaloid production in medicinal plants like C. roseus.  相似文献   
76.
The effect of plant growth promoting rhizobacteria (PGPR) like Pseudomonas fluorescens on growth parameters and the production of ajmalicine were investigated in Catharanthus roseus under drought stress. The plants under pot culture were subjected to 10, 15 and 20 days interval drought (DID) stress and drought stress with Pseudomonas fluorescens at 1mgl(-1) and 1mgl(-1)Pseudomonas fluorescens alone from 30 days after planting (DAP) and regular irrigation was kept as control. The plants were uprooted on 41 DAS (10 DID), 46 DAS (15 DID) and 51 DAS (20 DID). Drought stress decreased the growth parameters and increased the ajmalicine content. But the treatment with Pseudomonas fluorescens enhanced the growth parameters under drought stress and partially ameliorated the drought induced growth inhibition by increasing the fresh and dry weights significantly. The ajmalicine content was again increased due to Pseudomonas fluorescens treatment to the drought stressed plants. From the results of this investigation, it can be concluded that, the seedling treatments of native PGPRs can be used as a good tool in the enhancement of biomass yield and alkaloid contents in medicinal plants, as it provides an eco-friendly approach and can be used as an agent in water deficit stress amelioration.  相似文献   
77.
Even though literature available on EPDM is abundant, the data on physical, mechanical, thermal, interface properties and ablative performance as specifically required for the design and acceptance of internal insulation of large Composite Rocket Motor Casing is scant in the plethora of literature available in the subject of EPDM insulation. This gave the impetus to take up this experimental work wherein most promising formulation of EPDM with Kevlar and silica as reinforcing fillers and with only silica as reinforcing filler were thoroughly characterized for the insulation requirements of large Composite Rocket Motor Casing and compared with the performance of proven Nitrile rubber based insulation. The significant findings which are unique, are discussed in this paper.  相似文献   
78.
Journal of Thermal Analysis and Calorimetry - The oxidation behavior of U-6&nbsp;mass% Zr alloy was studied by using thermogravimetric technique. Oxidation reaction was carried out by heating...  相似文献   
79.

Sinefungin (SFN) is an antiviral agent of dengue (DENV) and Zika (ZIKV) viruses with IC50 values of 0.63 and 1.18 µM, respectively. The ADMET properties of SFN revealed that the SFN molecule can be used as an oral drug due to its good solubility nature. The molecular docking analysis of SFN molecule with RNA capping site of DENV and ZIKV NS5 MTase was performed. From this, the SFN-DENV MTase was found to be the best, based on binding energy (??7.56 kcal/mol) and intermolecular interactions. The geometrical parameters of the optimized conformation and docked conformations of SFN molecule are compared which indicated that the intermolecular interactions lead to the modifications of SFN conformation in active site. The molecular electrostatic potential map of SFN depicts the possible nucleophilic and electrophilic locations present in the molecule. The HOMO–LUMO based electronic properties such as electron affinity (A), electrophilicity (ω), electronegativity (χ) and global hardness (η) were calculated to determine the stability and toxicity of SFN molecule. Fukui function and NBO analysis of SFN were also computed.

  相似文献   
80.
The fluorescence quenching of 9-aminoacridine by certain biologically important catechols and rutin was investigated using absorption, steady state and time resolved fluorescence measurements. The in vitro-antioxidant activities of the above compounds were studied using deoxyribose degradation assay and nitric oxide scavenging assay. The experimental results showed that the fluorescence of 9-aminoacridine was quenched by quencher molecules via forming ground state complex. The bimolecular quenching rate constant k(q), binding constant (K) and number of binding sites (n) were calculated at different temperatures from relevant fluorescence data. Static quenching mechanism was supported by lifetime measurement. The free energy change (ΔG(et)) for electron transfer process was calculated by Rehm-Weller equation. The binding distance of 4-nitrocatechol with 9-aminoacridine was obtained according to Forster's non-radiative energy transfer theory. Nature of binding forces and their interactions was probed based on thermodynamic parameters.  相似文献   
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