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101.
M. Wilkinson B. Mehlig 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,1(4):397-398
We discuss the absorption of electromagnetic radiation in small conducting particles, in the case where the electron motion
is diffusive. We refine an earlier theory in which we calculated the absorption coefficient using an effective potential describing
the screened electric field. Our new theory incorporates the effects of non-locality in the electrical conductivity, and shows
how the two limiting behaviours of the effective potential at high and low frequencies can be derived from a unified theory.
Our results are in full agreement with our earlier calculation.
Received: 3 November 1997 / Accepted: 29 January 1998 相似文献
102.
Mixed crystals of betaine, phosphite and betaine phosphate have been investigated using broadband di-electric spectroscopy
at frequencies 10−1Hz≤ν≤109Hz and temperatures 1.5 K≤T≤300 K for several betaine phosphate concentrationsx. For 0.2≤x≤0.65 an orientational glass state is found at low temperatures. The broad susceptibility spectra were analyzed using the
concepts of distributions of relaxation times and of distributions of energy barriers. A critical comparison of the different
approaches is given. In the mixed crystals that show antiferroelectric order at low temperatures, charge transport phenomena
are studied. The static permittivity of the proton glass-forming crystals is analyzed, in terms of effectively one- and three-dimensional
Ising models that incorporate random fields and random bonds. 相似文献
103.
Received: 15 August 1997/Accepted: 13 November 1997 相似文献
104.
The reported two peaks near 65.1 keV and 66.9 keV are not only the tri-photon coincidence counts but also the single photon of K-shell x-rays. These peaks contain two major decay components, i.e. fast T0/3 decay and slow 5.8-day decay. The 5.8-day decay corresponds to the ^195m Pt transition and the T0/3 decay corresponds to the reported tri-photon effect. According to the updated report from the vendor, our rhodium sample probably contains the unlisted impurity of 7-ppm platinum. The ^195m Pt transition is generated from this extremely small amount of Pt im- purity by the bremsstrahlung irradiation. The peak at 98.8keV in Fig. 相似文献
105.
K. G. Wang 《Zeitschrift für Physik B Condensed Matter》1995,99(1):593-597
A nonequilibrium statistical mechanical theory for grain growth is presented in this paper. The fluctuation of grain growth
is determined from the self similarity of grain size distribution. The grain size distribution scaled by the averaged size
is derived under the condition that the volume of specimen is strictly conserved. The growth law of grain is also derived.
The scaled grain size distribution are compared with the associating lognormal distribution which is usually used in the analysis
of the experimental results. It has been found that the theoretical results is in good agreement with experimental results. 相似文献
106.
M. Paasch M. Winterlich R. Böhmer R. Sonntag G. J. McIntyre A. Loidl 《Zeitschrift für Physik B Condensed Matter》1995,99(1):333-338
The χ,T phase diagram of (NH4I)x(KI)1−x has been determined using neutron diffraction experiments and dielectric spectroscopy. At low temperatures and with decreasing
χ, the sequence γ, β, ε and glass phase has been detected. The critical concentration χc≈0.55 separates the glassy phase with frozen-in orientational disorder from the ε phase which reveals long-range orientational
order. Close to χc our experiments reveal evidence for two subsequent glass transitions. 相似文献
107.
Jürgen H. Werner 《Applied Physics A: Materials Science & Processing》1988,47(3):291-300
This paper proposes and examines three different plots for the determination of the saturation current, the ideality factor, and the series resistance of Schottky diodes and solar cells from the measurement of a single current (I)/voltage(V) curve. All three plots utilize the small signal conductance and avoid the traditional Norde plot completely. A test reveals that the series resistance and the barrier height of a test diode can be determined with an accuracy of better than 1%. Finally it is shown that a numerical agreement between measured and fittedI/V curves is generally insufficient to prove the physical validity of current transport models. 相似文献
108.
韩厚德 《高等学校计算数学学报(英文版)》1995,(2)
Here we derive a new representation of the derivative of the double-layer potential for harmonic elastic waves in R3.Based on this new representation,the Neumann internal problem and the Neumann external problem of harmonic elastic waves are reduced to a system of boundary integro-differential equations,which is convenient for numerical approximation. 相似文献
109.
M. Kopcewicz U. Gonser H. G. Wagner 《Applied Physics A: Materials Science & Processing》1980,23(1):1-6
The influence of radio frequency (rf) magnetic fields on the properties of amorphous Fe40Ni40B20 was studied using Mössbauer spectroscopy. The measurements were performed with frequencies of 67 and 53 MHz and rf field intensity in the range of 1 to 12 Oe. The narrowing of the hyperfine spectra due to the rf field and the formation of rf sidebands were observed. The effect of instability and crystallization of the amorphous metal enhanced by the rf field at temperatures much lower than the crystallization temperature was observed. 相似文献
110.
2 monitor designed for field applications using room-temperature diode lasers are presented. Near-infrared DFB lasers operating
at 1.57 μm and around 2.0 μm have been used for CO2 measurements. At ambient concentration levels a resolution of more than two orders of magnitude has been demonstrated at
1.57 μm, at 2 μm the precision is in the order of 0.1 ppm CO2, and for trace analysis a detection limit of 10 ppb has been obtained. The measurements demonstrate the capability of near-infrared
DFB diode lasers for the precise determination of CO2 concentrations as required for climatological, medical, or industrial applications.
Received: 24 February 1998/Revised version: 27 April 1998 相似文献