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251.
In an attempt to study the scope of a theorem due to Pati, the authors have established that φ(t) logK|t∈B
u
V in (0,π)⟹ΣA
n
(x) is |C, 0,β| forβ>1, at the pointt = x. 相似文献
252.
Md. Aquil Akhter Panchanan Pramanik Mukul Biswas 《Journal of Polymer Science.Polymer Physics》1987,25(2):339-352
Poly[(N-benzyldiphenylamino)methane] was synthesized by the condensation polymerization of benzyldiphenylamine and formalin (30% HCOH in water) and examined for electrical and optoelectronic properties. Dark conductivity and photoconductivity of the polymer film were investigated by steady-state measurements. Current-voltage characteristics and intrinsic photoconduction of the polymer in the visible wavelength range were studied. A superlinear current increase is tentatively explained in the light of the Poole-Frenkel effect. Dielectric constant and dielectric loss parameters of the polymer are independent of frequency (50 Hz–10 kHz) and temperature (273–323 K), respectively. The growth and decay rates of the photocurrent depend on the applied voltage, and the photocurrent varies directly with the light intensity. The activation energies for dark conductivity and photoconductivity are 1.16 eV and 1.05 eV, respectively, and the optical energy band gap as evaluated from absorption coefficient spectra is 2.86 eV. 相似文献
253.
Essaid Zerrad Richard Triplett Anjan Biswas 《International Journal of Theoretical Physics》2009,48(6):1583-1588
A new numerical method of solving integro-differential equations appearing in the theory of atomic and nuclear scattering
systems has been devised. It is termed Singular Value Decomposition Method (SVD). It consists in expanding the exchange kernel
into a number of separable terms by means of the Singular Value Decomposition and then iterating over the remainder. In this
paper, we extend our SVD method to the scattering of low energy electron-helium which has been the subject of interest, both
theoretically and experimentally. We compare our results with the Moments Method which is widely used. The Moments Method
consists of making an expansion of the solution into an especially favorable basis that takes care of the non-exchange part
of the Hamiltonian. 相似文献
254.
255.
256.
M. Chandra Sekhar P. Kondaiah S.V. Jagadeesh Chandra G. Mohan Rao S. Uthanna 《Applied Surface Science》2011,258(5):1789
Titanium dioxide (TiO2) films have been deposited on glass and p-silicon (1 0 0) substrates by DC magnetron sputtering technique to investigate their structural, electrical and optical properties. The surface composition of the TiO2 films has been analyzed by X-ray photoelectron spectroscopy. The TiO2 films formed on unbiased substrates were amorphous. Application of negative bias voltage to the substrate transformed the amorphous TiO2 into polycrystalline as confirmed by Raman spectroscopic studies. Thin film capacitors with configuration of Al/TiO2/p-Si have been fabricated. The leakage current density of unbiased films was 1 × 10−6 A/cm2 at a gate bias voltage of 1.5 V and it was decreased to 1.41 × 10−7 A/cm2 with the increase of substrate bias voltage to −150 V owing to the increase in thickness of interfacial layer of SiO2. Dielectric properties and AC electrical conductivity of the films were studied at various frequencies for unbiased and biased at −150 V. The capacitance at 1 MHz for unbiased films was 2.42 × 10−10 F and it increased to 5.8 × 10−10 F in the films formed at substrate bias voltage of −150 V. Dielectric constant of TiO2 films were calculated from capacitance–voltage measurements at 1 MHz frequency. The dielectric constant of unbiased films was 6.2 while those formed at −150 V it increased to 19. The optical band gap of the films decreased from 3.50 to 3.42 eV with the increase of substrate bias voltage from 0 to −150 V. 相似文献
257.
The measurement of very weak overtone spectroscopic line shape of water molecule is performed using wavelength modulation
spectroscopy (WMS). In this work a high resolution near infrared diode laser spectrometer is used to record first derivative
(1f) signal of buffer gas Helium and Carbon dioxide broadened water vapour transitions around 820 nm wavelength region. The
effect of collision due to perturber pressure on signal to noise ratio (SNR) is discussed. The Lorentzian HWHM of observed
1f signal is calculated. The comparison is made between collisional broadening of water vapour transition broadened by inert
gas Helium and high quadrupole moment active gas Carbon dioxide. 相似文献
258.
The electronic charge distribution in tetragonal closed packed (tcp) metal is approximated by a collection of spherical charge
clouds situated midway between the ions. The anisotropy of the charge distribution is parameterized in terms of a charge shift
δ derivable from the lattice parameters and the elastic coefficients of the metal. The electric field gradient (EFG) in the
metal can be obtained through lattice summations over the charges. Numerical calculations are made to obtain the EFG in pure
indium and indium-based dilute impurity alloys. Fairly good agreement with the experiments is achieved. 相似文献
259.
Summary Polar heteroatomic concentrates were separated from deasphalted oils and asphalts of indigenous crudes by various separation techniques. Conditions have been standardized for its separation using Fuller's earth as adsorbent, and data is compared with those obtained by the techniques reported in the literature. Semiquantitative estimates of phenols, pyrrols, carboxylic acids and amides in the concentrates were also made by IR spectrometry. 相似文献
260.
Amorphous metal Fe10Ni70Si8B12 has been studied by Mössbauer spectroscopy without and with an weak applied field in the plane of ribbons. Reentrant properties have been confirmed with the existence of a canted state at low temperature. Studies with different values of the applied field have shown that a field near 50 0e is sufficient to saturate the average direction of the ferromagnetism. 相似文献