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271.
Sarika Bhide V. M. Datar Satyajit Jena S. D. Kalmani N. K. Mondal G. K. Padmashree B. Satyanarayana R. R. Shinde P. Verma 《Pramana》2007,69(6):1015-1023
We are currently developing and studying the performance of glass RPC prototypes, under the INO detector R&D programme. While
we were successful in building and characterising a large number of chambers using local glass, these have met with severe
aging problems after a few months of continuous operation. We have then built a couple of RPCs using a Japanese glass. We
report in this paper on our long term stability tests of these RPCs. We also present some of our recent results on tracking
of cosmic ray muons in a stack of glass RPCs.
India-based Neutrino Observatory Collaboration 相似文献
272.
273.
B. Ramachandra Rao J. Satyanarayana Murty 《Zeitschrift für Physik A Hadrons and Nuclei》1958,152(4):440-447
Assuming the validity ofRaman andNath's simplified theory for small widths of weak sound fields, an elegant and simple method is presented to derive an expression for the intensity of the first order in the case of weak sound fields. Expressions obtained are found to be identical with those ofDavid, andBhatia andNoble. Extending this treatment to the case of diffraction by stationary waves it is shown that the intensity of a first order in this case is half that of the corresponding order for progressive waves and this result has also been verified experimentally. 相似文献
274.
275.
R.S. Ward A. Pelter I.R. Jack P. Satyanarayana B.V.Gopala Rao P. Subrahmanyam 《Tetrahedron letters》1981,22(41):4111-4114
Paulownin and gmelinol react with DDQ to give 4-pyrone derivatives. Gummadiol reacts under the same conditions to give a pyrone aldehyde and an unsaturated γ-lactone. 相似文献
276.
277.
Pressure induced phase transition in mercurous chloride has been studied by high pressure x-ray diamond anvil cell. The change in diffraction pattern started and ended at a pressure of about 5 kbar and 20 kbar respectively. The patterns recorded at 20 kbar could be indexed basing on an orthorhombic lattice, with lattice parametersa=4.23 Å,b=4.54 Å andc=10.44 Å. 相似文献
278.
279.
280.
Temperature and frequency dependence of dielectric constant and conductivity properties of Pb0.77K0.26Li0.2Ti0.25Nb1.8O6 (PKLTN) ceramics are modelled through the universal dielectric response (UDR). Partial substitution of Ti4+ for Nb5+ was compensated by charge and the creation of oxygen vacancies according to the Kroger-Vink notation. The electrons released by this reaction are captured by Nb5+ and Ti4+ to generate Nb3+ and/or Ti3+. The hopping of electrons between Nb5+–Nb3+ and Ti4+–Ti3+ are believed to participate in conductivity. Characterization of the dielectric constant has been performed from room temperature to 590°C in the frequency range from 45 Hz to 5 MHz. The measured dielectric constant obeyed Jonscher's dielectric dispersion relations: ε l = ε ∞ + sin(n(T)π/2)(a(T)/ε 0)(ωn ( T )?1) and ε ll = σ/iε 0 ω + cos(n(T)π/2)(a(T)/ε 0)(ωn ( T )?1). Cole-Cole plots inclined at an angle (1 ? n(T))π/2 and followed the trend of universal material behavior ε ∞ + A(T)(ωn ( T )?1). The exponent n(T) and coefficient A(T) = (a(T)S/L) exhibited a minimum and maximum at T c = 425°C, respectively. The conductivity studies show the contribution of the hopping of bound charge carriers to conduction in PKLTN. 相似文献