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31.
Luminescence properties of green‐emitting Ca2MgSi2O7:Eu2+ phosphor by a solid‐state reaction method
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A europium (Eu)‐doped di‐calcium magnesium di‐silicate phosphor, Ca2MgSi2O7:Eu2+, was prepared using a solid‐state reaction method. The phase structure, particle size, surface morphology, elemental analysis, different stretching mode and luminescence properties were analyzed by X‐ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) with energy dispersive X‐ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL) and mechanoluminescence (ML). The phase structure of Ca2MgSi2O7:Eu2+ was an akermanite‐type structure, which belongs to the tetragonal crystallography with space group P4?21m; this structure is a member of the melilite group and forms a layered compound. The surface of the prepared phosphor was not found to be uniform and particle distribution was in the nanometer range. EDX and FTIR confirm the components of Eu2+‐doped Ca2MgSi2O7 phosphor. Under UV excitation, the main emission peak appeared at 530 nm, belonging to the broad emission ascribed to the 4f65d1→4f7 transition of Eu2+. The ML intensity of the prepared phosphor increased linearly with increasing impact velocity. A CIE color chromaticity diagram and ML spectrum confirmed that the prepared Ca2MgSi2O7:Eu2+ phosphor would emit green color and the ML spectrum was similar to that of PL, which indicated that ML is emitted from the same center of Eu2+ ions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
32.
Rajesh Kumar G Mrudula Spurthi K Kishore Kumar G Mohanalatha Kurapati Saraswati M Mohini Aiyengar T Chiranjeevi P Srilatha Reddy G Nivas S Kaushik P Sanjib Sahu K Surekha Rani H 《PloS one》2015,10(3)
Background
Coronary Artery Disease (CAD) is clearly a multifactorial disease that develops from childhood and ultimately leads to death. Several reports revealed having a First Degree Relatives (FDRS) with premature CAD is a significant autonomous risk factor for CAD development. C - reactive protein (CRP) is a member of the pentraxin family and is the most widely studied proinflammatory biomarker. IL-18 is a pleiotrophic and proinflammatory cytokine which is produced mainly by macrophages and plays an important role in the inflammatory cascade.Methods and Results
Hs-CRP levels were estimated by ELISA and Genotyping of IL-18 gene variant located on promoter -137 (G/C) by Allele specific PCR in blood samples of 300 CAD patients and 300 controls and 100 FDRS. Promoter Binding sites and Protein interacting partners were identified by Alibaba 2.1 and Genemania online tools respectively. Hs-CRP levels were significantly high in CAD patients followed by FDRS when compared to controls. In IL-18 -137 (G/C) polymorphism homozygous GG is significantly associated with occurrence of CAD and Hs-CRP levels were significantly higher in GG genotype subjects when compared to GC and CC. IL-18 was found to be interacting with 100 protein interactants.Conclusion
Our results indicate that Hs-CRP levels and IL-18-137(G/C) polymorphism may help to identify risk of future events of CAD in asymptomatic healthy FDRS. 相似文献33.
34.
S. K. Sahoo S. S. Giri S. Chandra A. K. Sahu 《Zeitschrift fur angewandte Ichthyologie》2010,26(4):609-611
The aim of the experiment was to evaluate the growth and survival of Horabagrus brachysoma larvae at different stocking densities (3, 7, 13, 20, 27 and 33 larvae L?1) during their hatchery phase. Total length and wet weight of the larvae consistently decreased (P < 0.05) at the end of 14 and 28 days of rearing as the density increased. The specific growth rate was significantly (P < 0.05) highest at three larvae L?1 compared to the other five densities. The percent weight gain and survival of larvae was also highest at lowest density. The observation corroborates that catfish larvae can be reared at low densities in stagnant water conditions. Considering the value of larval growth, survival and overall weight gain, the stocking density of seven larvae L?1 has been identified as the maximum for larval rearing of H. brachysoma under hatchery conditions. 相似文献
35.
K. Sivakumar Maloy Kumar Sahu T. Thangaradjou L. Kannan 《Indian journal of microbiology》2007,47(3):186-196
Marine actinobacteriology is one of the major emerging areas of research in tropics. Marine actinobacteria occur on the sediments
and in water and also other biomass (mangrove) and substrates (animal). These organisms are gaining importance not only for
their taxonomic and ecological perspectives, but also for their unique metabolites and enzymes. Many earlier studies on these
organisms were confined only to the temperate regions. In tropical environment, investigations on them have gained importance
only in the last two decades. So far, from the Indian peninsula, 41 species of actinobacteria belonging to 8 genera have been
recorded. The genus, Streptomyces of marine origin has been more frequently recorded. Of 9 maritime states of India, only 4 have been extensively covered for
the study of marine actinobacteria. Most of the studies conducted pertain to isolation, identification and maintenance of
these organisms in different culture media. Further, attention has been focused on studying their antagonistic properties
against different pathogens. Their biotechnological potentials are yet to be fully explored. 相似文献
36.
N. K. Ramaswamy N. S. Nathawat J. S. Nair H. R. Sharma S. M. Kumawat Govind Singh M. P. Sahu S. F. D’souza 《Photosynthetica》2007,45(3):477-480
Pearl millet (Pennisetum glaucum L. cv. HHB-67) seeds were pre-soaked in sulphydryl compounds (dithiothreitol, thioglycollic acid, thiourea, and cysteine).
In plants at 59 and 67 d after sowing (DAS), activities of photosystem (PS) 2 (ferricyanide site) and PS1, both chloroplastic
and total superoxide dismutase, glutathione reductase, and glutathione-S-transferase increased after all sulphydryl pre-treatments
at both stages of plant development. Also dry matter of plant parts sampled at 55 DAS was higher after thiol-treatments in
comparison with control. 相似文献
37.
Glia maturation factor (GMF), a highly conserved brain-specific protein, isolated, sequenced and cloned in our laboratory.
Overexpression of GMF in astrocytes induces the production and secretion of granulocyte-macrophage-colony stimulating factor
(GM-CSF), and subsequent immune activation of microglia, expression of several proinflammatory genes including major histocompatibility
complex proteins, IL-1β, and MIP-1β, all associated with the development of experimental autoimmune encephalomyelitis (EAE),
the animal model for multiple sclerosis. Based on GMF’s ability to activate microglia and induce well-established proinflammatory
mediators, including GM-CSF, we hypothesize that GMF is involved in the pathogenesis of inflammatory disease EAE. In this
present investigation, using GMF-deficient mice, we study the role of GMF and how the lack of GMF affects the EAE disease.
Our results show a significant decrease in incidence, delay in onset, and reduced severity of EAE in GMF-deficient mice, and
support the hypothesis that GMF plays a major role in the pathogenesis of disease. 相似文献
38.
Paul Prajita Patel Paritosh Verma Suresh K. Mishra Pragyan Sahu Bikash R. Panda Pritam Kumar Kushwaha Gajraj Singh Senapati Shantibhusan Misra Namrata Suar Mrutyunjay 《Cell biology and toxicology》2022,38(1):111-127
Cell Biology and Toxicology - The key to bacterial virulence relies on an exquisite balance of signals between microbe and hosts. Bacterial toxin–antitoxin (TA) system is known to play a... 相似文献
39.
40.
False smut is a disease of rice inflorescence. The existing systems of disease severity assessment for rice false smut disease are not very sensitive as the ball quality and also the impact of false smut on filled grain number and grain‐filling were not under consideration. Here, a precise assessment method to evaluate the severity of the disease was developed. The ‘yield representative’ (YR) based on ‘mean floret wt.’ and ‘filled grain %’ was simulated for the precise disease severity assessment of rice false smut disease. The single floret weight envisages major yield components irrespective of the type of panicle. Correlation between YR and major yield attributes was studied, and it was observed that YR had significant correlation with ‘filled grain %’ (0.77–0.95) and ‘single spikelet weight’ (0.88–0.98). Significant negative correlation of YR was observed with the chaff percentage, false smut ball number and ball weight. This YR‐based methodology was utilized to assess the disease severity in nine rice cultivars. The disease severity in those nine cultivars was evaluated by the already existing methodologies also. The disease severity measured by the present technique was compared with the disease severity assessed by the old methodologies. The procedure adapted here for disease severity measurement was found to be more informative and useful. It was observed that in case of mild infection, the false smut was enhancing yield attributes. The high‐yielding rice varieties Savitri and Gayatri were found to be tolerant to false smut and may be used as resistant donors. 相似文献