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11.
Mechanoluminescence (ML) and thermoluminescence (TL) in barium zirconium titanate (BZT) is reported for the first time. The BZT powder sample, belonging to perovskite category is synthesized using solid state reaction technique. The sample is prepared at a temperature of 1200 °C. The obtained specimen is thoroughly characterized paying particular attention to their structure, composition, morphology and optical properties. The surface morphology and structural properties are analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD patterns confirm the formation of crystalline perovskite type cubic structure. Also, highly agglomerated, porous and regular shaped particles are seen by SEM. The optical properties of as prepared sample is presented and discussed in terms of ML and TL. The ML intensity is found to be maximum for the sample irradiated for 10 min. More than one maxima in TL glow curve reveals that the traps are distributed in separate groups at different depths and corresponding values are calculated using initial rise method. 相似文献
12.
Sandip Kumar Dash Minakshi Sharma Shashi Khare Ashok Kumar 《Applied biochemistry and biotechnology》2013,171(1):198-208
Human brain bacterial meningitis is a life-threatening disease caused mainly by Neisseria meningitidis, lead to damage of the outer membrane covering (meninges) of brain or even death. The usual methods of diagnosis are either time-consuming or have some limitations. The specific rmpM (reduction-modifiable protein M) virulent gene based genosensor is more sensitive, specific, and can detect N. meningitidis directly from the patient cerebrospinal fluid in 30 min including 1-min response time. 5′-Thiol-labeled single-stranded DNA (ssDNA) probe was immobilized onto screen-printed gold electrode (SPGE) and hybridized with denatured (95 °C) single-stranded genomic DNA (ssG-DNA) for 10 min at 25 °C. The electrochemical response was measured by cyclic voltammetry, differential pulse voltammetry (DPV) and electrochemical impedance using redox indicators. The sensitivity of the genosensor was 9.5087?(μA/cm2)/ng with DPV and limit of detection was 3 ng/6 μL ssG-DNA. The immobilization of the ssDNA probe and hybridization with ssG-DNA from N. meningitidis was characterized by atomic force microscopy and Fourier transform infrared spectroscopy. The rmpM genosensor was stable for 6 months at 4 °C with 10 % loss in initial DPV current. The advantage of rmpM genosensor is to detect bacterial meningitis simultaneously in multiple patients using SPGE array during an outbreak of the disease. 相似文献
13.
R. Khare P.K. Shukla G.K. Mishra C. Mukherjee S. Talwar V.K. Dubey P. Saxena J.K. Mittal 《Optics Communications》2009,282(19):3850-3853
We present an analytical and experimental study of a novel confocal optical pulse stretcher (COPS). The simple and passive pulse stretcher consists of two concave mirrors and a scraper beam-splitter and its optical configuration ensures a perfect spatial overlapping of laser pulses at the beam-splitter. The pulse stretcher is compact and suitable for laser pulses of large divergences. The confocal optical pulse stretcher is demonstrated on a pulsed copper vapour laser to convert a 40 ns (1/e2 % points) pulse into a 55 ns with reduction of peak power by a factor of 1.375 without loss of pulse energy. 相似文献
14.
Background
Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH. 相似文献15.
Several novel glycofuranoses disaccharides related to mycobacterial cell wall polysaccharides were synthesized regio- and stereoselectively using 2,3,5-tri-O-benzoyl-alpha-D-arabinofuranosyl trichloroacetimidate as a glycosyl donor. 相似文献
16.
Chandrashekhar Khare 《Proceedings of the American Mathematical Society》2003,131(10):3021-3023
In this note we relate the property of a semisimple -adic Galois representation being ``-split' to its having abelian image.
17.
Overtone spectrum of o, m and p-nitrobenzaldehydes and p-chlorobenzaldehyde has been studied in 2000–12000 cm−1 region. Vibrational frequencies and anharmonicity constants for aryl as well as alkyl CH stretch vibrations have been determined.
We have also determined the internuclear distances for the aryl CH bond in the different molecules. The small variation observed
in these distances is an indication of the substitution effect.
It is observed that in the case of p-disubstituted benzens, the shift in aryl CH bond is proportional to sum of the Hammet σ of the substituents. However in the
case of o-disubstituted benzenes it is only 80% of the para-substituted shift. 相似文献
18.
Mona Khare Akhilesh Kumar Singh 《Journal of Mathematical Analysis and Applications》2008,344(1):238-252
The aim of this paper is to introduce and investigate the concept of pseudo-atoms of a real-valued function m defined on an effect algebra L; a few examples of pseudo-atoms and atoms are given in the context of null-additive, null-null-additive and pseudo-null-additive functions and also, some fundamental results for pseudo-atoms under the assumption of null-null-additivity are established. The notions of total variation |m|, positive variation m+ and negative variation m− of a real-valued function m on L are studied elaborately and it is proved for a modular measure m (which is of bounded total variation) defined on a D-lattice L that, m is pseudo-atomic (or atomic) if and only if its total variation |m| is pseudo-atomic (or atomic). Finally, a Jordan type decomposition theorem for an extended real-valued function m of bounded total variation defined on an effect algebra L is proved and some properties on decomposed parts of m such as continuity from below, pseudo-atomicity (or atomicity) and being measure, are discussed. A characterization for the function m to be of bounded total variation is established here and used in proving above-mentioned Jordan type decomposition theorem. 相似文献
19.
Background
Organic light emitting devices (OLED) are becoming important and characterisation of them, in terms of structure, charge distribution, and intermolecular interactions, is important. Tris(8-hydroxyquinolinato)-aluminium(III), known as Alq3, an organomettalic complex has become a reference material of great importance in OLED. It is important to elucidate the structural details of Alq3 in its various isomeric and solvated forms. Solid-state nuclear magnetic resonance (NMR) is a useful tool for this which can also complement the information obtained with X-ray diffraction studies. 相似文献20.
Ayi A. Ayi Varsha Khare Peter Strauch Jér?me Girard Katharina M. Fromm Andreas Taubert 《Monatshefte für Chemie / Chemical Monthly》2010,41(9):1273-1278