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221.
Kamlesh Pandey Mrigank Mauli Dwivedi Markandey Singh S.L. Agrawal 《Phase Transitions》2013,86(4):343-356
Dispersal of nanofillers in polymer electrolytes have shown to improve the ionic properties of Polyethylene oxide (PEO)-based polymer electrolytes in recent times. The effects of different nanoferrite fillers (i.e., Al–Zn ferrite, Mg–Zn ferrite, and Zn ferrite) on the electrical transport properties have been studied here on the composite polymer electrolyte system. The interaction of salt/filler with electrolyte has been investigated by XRD studies. SEM image and infrared spectral studies give an indication of nanocomposite formation. In conductivity studies, all electrolyte systems are seen to follow universal power law. Composition dependence (with ferrite filler) gives the maximum conductivity in [93PEO–7NH4SCN]: X ferrite (where X?=?2% in Al–Zn ferrite, 1% Mg–Zn ferrite, and 1% Zn ferrite) system. 相似文献
222.
In the present work, studies have been made to analyze the sensitivity, response, recovery time and sensing mechanism of Pd-doped thick film SnO2 sensor for detection of LPG. To achieve this, thick film Pd-doped (0.25 and 1% by weight in available Indium doped SnO2 thick film paste supplied by ESL, USA) along with an undoped (Indium doped) SnO2 sensors were fabricated on a 1″ × 1″ alumina substrate. It consists of a gas sensitive layer (doped SnO2), a pair of electrodes underneath the gas sensing layer serving as a contact pad for sensor. Also, a heater element on the backside of the substrate was printed for generating appropriate operating temperature at the substrate necessary for acquiring gas sensing properties. The sensor doped with 1% palladium showed the maximum sensitivity of 72% at 350 °C for 0.5% concentration of LPG. Possible detailed sensing mechanism of Pd-doped SnO2 sensor for LPG detection has been proposed. 相似文献
223.
The performance of Pd gate MOS hydrogen sensor was studied using C–V and G–V characteristics. The device was fabricated on p-type <100> (1–6Ω cm.) silicon with thermal oxide layer of about 100 Å. The C–V and G–V responses of sensor were measured at different frequencies (1 kHz, 10 kHz, and 100 kHz) upon exposure to hydrogen (conc. 1–8%) at room temperature. It was observed that value of zero bias capacitance decreases with increase in frequency as well as hydrogen concentration. The inversion potential (Vinv.) and flat band voltage (VFB) of the device approach higher values as frequency is reduced. Interface trap density (Nit) was also determined corresponding to the peak in the conductance curve, using a bias scan conductance method at fixed frequency. Nit was found to be decreasing with increasing concentrations of hydrogen. The sensor showed better sensitivity at lower frequency. 相似文献
224.
I. G. Abdullaev J. C. Adloff I. G. Bersina B. Bisplinghoff V. Bradnova R. Brandt V. S. Butsev H. H. Cui M. Debeauvais K. K. Dwivedi E. M. Friedlander S. Gosh S. L. Guo S. Heise M. I. Krivopustov B. A. Kulakov E. J. Langrock C. Laue L. Lerman V. P. Perelygin Th. Schmidt A. N. Sosnin P. Vater S. Vonderau X. L. Wang M. Zamani 《Radiation measurements》1995,25(1-4):219-230
An extended Cu-target was irradiated with 22 and 44 GeV carbon ions. The target was in contact with a (CH2)n-block for the moderation of secondary neutrons. Small holes in the moderator were filled with either lanthanium salts or uranium oxide. The reaction 139La (n,γ) 140La
was studied via the decay of 140La (40 h), and the reaction 238U (n, γ) 239U
239Np
was studied via the decay of 239Np (2.3 d). In addition, a variety of solid state nuclear track detectors (SSNTD) were used. Results will be presented. The yields for the formation of (n, γ) products agree essentially with other experiments on extended targets carried out at the Synchrophasotron LHE, JINR (Dubna). To a first approximation, the breeding rate of (n, γ) products, as well as the specific track density, seen with several SSNTDs, doubles when the carbon energy is increased from 22 to 44 GeV. If, however, results at 44 GeV are compared in detail to those at 22 GeV, we observe an excess of (37 ± 9) % in the experimentally observed 239Np-breeding rate over theoretical estimations. Experiments using solid state nuclear track detectors are giving similar results. We also observed in the past such excess in the yield of other secondary particles in relativistic heavy ion interactions above a total energy of approximately 35–40 GeV. 相似文献
225.
We study the effect of the mass and charge dynamics on the collective behaviour of a dusty plasma. It is shown that the finite
non-zero streaming velocity of the dust grains leads to a novel coupling of the dust mass fluctuation with other dynamic variables
of the plasma and the grains. The mass fluctuations causes a collisionless dissipation and provides an alternate channel for
the beam mode instability to occur. Physically the negative energy wave associated with the beam mode couples to the mass
fluctuation induced dissipative medium to produce the instability. We conclude that the higher value of the ion mass density
to the dust mass density ratio reduces the threshold value for the onset of the instability. Its application in the astrophysical
context is discussed. 相似文献
226.
Steady state level population of 15 levels of carbon-like ions: NeV, MgVII, SiIX, and SXI have been computed as a function
of electron density and temperature taking into account collisional processes and spontaneous radiative ones. Photo-excitation
among the ground term levels has also been considered. Knowing the level density, line intensities have been computed as a
function of electron density and temperature. This study indicates that line intensity ratios for carbon-like ions can be
used as a diagnostic in the determination of these two parameters of the solar plasma. The resulting line fluxes from these
ions at earth distance are compared with observation.
Presented at the 5th Annual Radio and Space Sciences Symposium, National Physical Laboratory New Delhi, January 1979. 相似文献
227.
A formal scheme has been set up to solve the triple and quadruple integral equations of certain type which occur in diffraction theory. The operational theory has been employed in the analysis and equations have been reduced to the solution of simultaneous Fredholm equations. 相似文献
228.
Pd(0), Rh(I), Rh(II), and Ru(II) complexes of 2,4-dithiouracil have been prepared. The structures of the complexes have been postulated on the basis of chemical analyses, infrared, visible spectral and magnetic susceptibility data. 相似文献
229.
Analytical study of the stimulated Brillouin scattering in a two-ion species plasma has been done using the hydrodynamical model. When strong nonlinear effect becomes significant i.e., when the quiver velocity of the electron becomes of the order of or greater than its thermal velocity, the damping becomes intensity dependent which modifies the results over the weak nonlinearity. In this regime the plasma behaves as a collisionless medium. The inclusion of the second species of the ions modifies the instability and decreases the growth rate. Its application in fusion plasma has been discussed. 相似文献