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801.
Naresh Degda Nimesh Patel Vishwnath Verma Mangalampalli Srinivas Kota Venkata Ramana Murthy Divi Haranath 《Luminescence》2023,38(2):176-187
A luminescent double perovskite phosphor Sr2YNbO6 doped with Eu3+ crystallized to the monoclinic phase and was synthesized successfully via a conventional high-temperature combustion method. The formation of the crystal structure, phase purity, and surface morphology were studied using X-ray diffraction patterns and scanning electron microscopy. The characteristic vibrations between the atoms of the functional groups present in phosphor were studied using Fourier transform infrared spectra analysis. The luminescence properties of the prepared phosphors were investigated in terms of photoluminescence (PL) and thermoluminescence (TL). PL excitation spectra exhibited charge transfer bands and the characteristic 4f6 transitions of Eu3+. A prominent PL emission was obtained for the phosphor doped with 4 mol% Eu3+ under the 396 nm excitation wavelength. PL emission quenching was observed for the higher doping concentrations due to a multipole–multipole interaction. A highly intense PL emission arose due to the hypersensitive 5D0–7F2 electric dipole transition of Eu3+ that dominated the emission spectra. The thermal stability of the phosphor was examined through temperature-dependent PL. The TL properties of the Sr2YNbO6 double perovskites irradiated with a 90Sr beta source at different doses were measured. The double perovskite phosphors under study showed a linear dose–response with increasing beta dose, ranging from 1 Gy to 10 Gy. Trapping parameters of the TL glow curves were determined using Chen's peak shape method and computerized glow curve deconvolution (CGCD). CGCD fitting of the TL glow curves revealed that it was consisted of three major peaks and followed second-order kinetics. The estimated activation energies were determined using different methods and were comparable and significant. 相似文献
802.
803.
Tammineni Venkata Surendra Selvaraj Mohana Roopan Maksudur R. Khan 《Biotechnology progress》2019,35(4):e2823
The rare earth metal oxide nanoparticles such as gadolinium oxide nanoparticles (Gd2O3 NPs) have been synthesized by green synthesis process using methanolic extract of Moringa oleifera (M oleifera) peel. In this process, the Gd2O3 NPs formation was observed at 280–300 nm in UV–Vis spectroscopy. The XRD pattern of the synthesized Gd2O3 NPs was exactly matched with JCPDS No 3-065-3181which confirms the crystalline nature of Gd2O3 NPs. In addition, Energy-dispersive X-ray spectroscopy (EDX) analysis was stated that Gd and O elements were present as 70.31 and 29.69%, respectively in Gd2O3 NPs. The SEM and TEM analysis were said Gd2O3 NPs are in rod shape and 26 ± 2 nm in size. Further the synthesized Gd2O3 NPs were confirmed by X-ray photoemission spectroscopy (XPS). The synthesized Gd2O3 NPs were further examined for anti-fungal activity against Alternaria saloni (A saloni) and Sclerrotium rolfsii (S rolfsii) and it showed moderate activity. Also, Gd2O3 NPs evaluated as good antibacterial agent against different Gram +ve and Gram −ve bacteria. Moreover, the toxicity of the Gd2O3 NPs on red blood cells (RBCs) of the human blood was determined using hemolytic assay, the obtained results were stated the synthesized Gd2O3 NPs are nontoxic to the human erythrocytes. The photocatalytic activity against malachite green (MG) dye was tested and confirmed as 92% of dye was degraded within 2 hr by Gd2O3 NPs. The results were stated the green synthesized Gd2O3 NPs are good anti-fungal agents, nontoxic and we can use as a photocatalyst. Copyright © 2019 John Wiley & Sons, Ltd. 相似文献
804.
Yutaro Mori Amrendra K. Ajay Jae-Hyung Chang Shan Mou Huiping Zhao Seiji Kishi Jiahua Li Craig R. Brooks Sheng Xiao Heung-Myong Woo Venkata S. Sabbisetti Suetonia C. Palmer Pierre Galichon Li Li Joel M. Henderson Vijay K. Kuchroo Julie Hawkins Takaharu Ichimura Joseph V. Bonventre 《Cell metabolism》2021,33(5):1042-1061.e7
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805.
This report records the results of a pilot study on the usefulness of free amino acids in the taxonomy of the tribe Arundinelleae (Gramineae). The work, carried out on a Beckman Model 120C Amino Acid Analyzer and using 70% ethanolic extracts, indicated patterns of variation unrelated to those found in traditional classifications. The amino acid variation encountered should be considered taxonomic noise; this example supports the view that free amino acids may not be of general value in higher plant systematics. 相似文献
806.
Kanagaraj Muthu-Pandian Chanthini Ramaiah Soranam Annamalai Thanigaivel Sengodan Karthi Chinnadurai Sreenath Kumar 《Archives Of Phytopathology And Plant Protection》2013,46(13-14):729-753
AbstractTomato, the important vegetable crop faces yield loses by foliar disease, Early Blight caused by Alternaria solani and infestation by tobacco cut worm, Spodoptera litura. Synthetic pesticides used for disease and pest control resulted in environmental pollution as well as development of resistance. By way of a need to develop a new biopesticide, bacteria were tested for their anti-fungal and insecticidal activity. Volatile compounds and peptides from the bacteria, Bacillus subtilis, Staphylococcus aureus and Pseudomonas aeruginosa were able to inhibit the hyphal growth and melanin production of A. solani. S. aureus showed the highest inhibitory effect as well as reduced the disease severity. B. subtilis exhibited the highest mortality rate of 87% and 83% against I and II instar of S. litura, respectively. The bacteria offered effective biocontrol at 35?°C. Bioactive substances from the bacteria can be used as potential biocontrol agents against the pest and disease of tomato. 相似文献
807.
808.
Comprehensive Analysis of Varicella-Zoster Virus Proteins Using a New Monoclonal Antibody Collection
Tihana Lenac Rovi? Susanne M. Bailer Venkata R. Pothineni Werner J. D. Ouwendijk Hrvoje ?imi? Marina Babi? Karmela Mikli? Suzana Mali? Marieke C. Verweij Armin Baiker Orland Gonzalez Albrecht von Brunn Ralf Zimmer Klaus Früh Georges M. G. M. Verjans Stipan Jonji? Jürgen Haas 《Journal of virology》2013,87(12):6943-6954
Varicella-zoster virus (VZV) is the etiological agent of chickenpox and shingles. Due to the virus''s restricted host and cell type tropism and the lack of tools for VZV proteomics, it is one of the least-characterized human herpesviruses. We generated 251 monoclonal antibodies (MAbs) against 59 of the 71 (83%) currently known unique VZV proteins to characterize VZV protein expression in vitro and in situ. Using this new set of MAbs, 44 viral proteins were detected by Western blotting (WB) and indirect immunofluorescence (IF); 13 were detected by WB only, and 2 were detected by IF only. A large proportion of viral proteins was analyzed for the first time in the context of virus infection. Our study revealed the subcellular localization of 46 proteins, 14 of which were analyzed in detail by confocal microscopy. Seven viral proteins were analyzed in time course experiments and showed a cascade-like temporal gene expression pattern similar to those of other herpesviruses. Furthermore, selected MAbs tested positive on human skin lesions by using immunohistochemistry, demonstrating the wide applicability of the MAb collection. Finally, a significant portion of the VZV-specific antibodies reacted with orthologs of simian varicella virus (SVV), thus enabling the systematic analysis of varicella in a nonhuman primate model system. In summary, this study provides insight into the potential function of numerous VZV proteins and novel tools to systematically study VZV and SVV pathogenesis. 相似文献
809.