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1.
G. Kh. Panova M. G. Zemlyanov P. P. Parshin A. A. Shikov R. A. Brand 《Physics of the Solid State》2010,52(4):771-775
The specific heat of decagonal Al71.3Ni24.0Fe4.7 and icosahedral Al62Cu25.5Fe12.5 quasicrystals and the Al55.0Si7.0Cu25.5Fe12.5 cubic phase approximating the structure of the icosahedral alloy has been studied in the temperature range 4.2–40.0 K. All
the three compounds exhibit low coefficients of the electronic heat capacity and pronounced deviations of the low-temperature
lattice heat capacity from a cubic temperature law in the range 5–10 K. The results obtained by the thermodynamic method and
inelastic neutron scattering have been compared and analyzed. It has been established that, at energies ɛ < 14 meV, the spectral
density of thermal vibrations in the icosahedral quasicrystal is substantially higher than those in the cubic approximant
and in decagonal quasicrystal. 相似文献
2.
N. Imanaka 《Ionics》2003,9(1-2):36-40
New types of multivalent ion conducting solid electrolytes have been extensively developed and their applications for chemical
sensors were investigated. Among the trivalent ion conductors, the highest ion conductivity was realized with the (AlxZr1−x)4/(4−x)Nb(PO4)3 solid electrolyte and the value reaches the region between yttria stabilized zirconia (YSZ) and calcia stabilized zirconia
(CSZ) of the representative oxide anion conductors. The above described Al3+ ion conducting (AlxZr1−x)4/(4−x)Nb(PO4)3 solid electrolyte was combined with YSZ, with accompanying the Y2O3-KNO2 solid solution as an auxiliary electrode for nitrogen monoxide (NO) gas sensing. The sensor response was rapid and a reproducible
output was continuously observed obeying the Nernst theoretical relationship in a typical NO gas content region in exhaust
gases.
Paper presented at the 9th EuroConference on Ionics, Ixia, Rhodes, Greece, Sept. 15 – 21, 2002. 相似文献
3.
Yu. F. Minenkov 《Il Nuovo Cimento D》1995,17(4):435-438
Summary The experimental temperature dependence of the heat capacityC
p(T) of solid tin (Sn) in its premelting region 402.07–502.22 K was investigated and two regions with different temperature
dependences ofC
p(T) were found. In the far (from the melting temperatureT
m) region 402.07–485.88 K the experimentalC
p(T) of Sn is described by the standard vacancy model. In the close region 485.88–502.22 K it is described by the formation
of complicated volumetric defects in the crystalline lattice of solid Sn near itsT
m. 相似文献
4.
Experiments are performed to determine the magnetic susceptibility of the icosahedral phase itself in the alloy Al62Cu25.5Fe12.5 in the temperature range 3.9–1100 K. A new regularity is observed — the curves of the temperature dependences of the susceptibility
and electrical conductivity are congruent.
Pis’ma Zh. éksp. Teor. Fiz. 69, No. 3, 206–210 (10 February 1999) 相似文献
5.
A study is reported of the thermoelectric and galvanomagnetic properties of n-Bi2Te3−x−y
SexSey solid solutions for 0.12⩽x⩽0.36 and 0.12⩽y⩽0.21 within the 80–300 K temperature region. The thermoelectric figure-of-merit Z has been found to correlate with the parameters of the many-valley energy-band model including anisotropic carrier scattering.
It is shown that a decrease in the constant-energy surface anisotropy and scattering anisotropy results in a growth of Z for optimum carrier concentrations in the solid solution.
Fiz. Tverd. Tela (St. Petersburg) 41, 187–192 (February 1999) 相似文献
6.
G. A. Petrakovskii L. I. Ryabinkina N. I. Kiselev D. A. Velikanov A. F. Bovina G. M. Abramova 《JETP Letters》1999,69(12):949-953
The magnetic, electric, magnetoresistive, and structural properties are investigated in the sulfide solid solutions FexMn1−2x
S, which are based on the antiferromagnetic semiconductor α-MnS (the fcc NaCl lattice). Colossal negative magnetoresistance
(δH∼−83% at 160 K for x ∼ 0.29), comparable to that observed in La-Ca-Mn-O polycrystals and films (δH∼−90% at 100 K and 40 kOe), is observed in compounds with intermediate concentrations 0.26<x<0.4, corresponding to the region
of incipient ferromagnetism.
Pis’ma Zh. éksp. Teor. Fiz. 69, No. 12, 895–899 (25 June 1999) 相似文献
7.
Elemental mixtures of Al, Cu, Fe powders with the nominal composition of Al70Cu20Fe10 were mechanically alloyed in a planetary ball mill for 80 h. Subsequent annealing of the as-milled powders were performed
at 600–800°C temperature range for 4 h. Structural characteristics of the mechanically alloyed Al70Cu20Fe10 powders with the milling time and the heat treatment were investigated by X-ray diffraction (XRD), differential scanning
calorimeter (DSC) and differential thermal analysis (DTA). Mechanical alloying of the Al70Cu20Fe10 did not result in the formation of icosahedral quasicrystalline phase (i-phase) and a long time milling resulted in the formation
of β-Al(Cu,Fe) solid solution phase (β-phase). The i-phase was observed only for short-time milled powders after heat treatment above 600°C. The β-phase was one of the major phases in the Al70Cu20Fe10 alloy. The w-Al7Cu2Fe1 phase (w-phase) was obtained only after heat treatment of the short-time milled and unmilled samples. The present investigation
indicated that a suitable technique to obtain a large amount of quasicrystalline powders is to use a combination of short-time
milling and subsequent annealing. 相似文献
8.
N. V. Sidorov M. N. Palatnikov N. N. Mel’nik V. T. Kalinnikov 《Journal of Applied Spectroscopy》2000,67(2):259-268
By recording the Raman spectra, concentrational restructurizations in the system of solid solutions NaTayNb1−yO3 were investigated. The regions of relatively stable existence of solid solutions (y<0.2, y>0.8) and the region of a rather
high disordering (0.2<y<0.9) with maximum deformation of the elementary cell at y=0.5 have been revealed. It is found that
at y=0.5 a concentrational phase transition is observed, and at y ∼ 0.25 and 0.8 concentrational restructurizations occur.
It is shown that the octahedral anions of BO6 are centrosymmetric when y<0.2 and y>0.9, and the system of solid solutions NaTayNb1−yO3 is antiferroelectric when y<0.2. In the range of concentrations 0.2<y< 0.9, the structure of NaTayNb1−yO3 is characterized by the presence of polar clusters.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 2, pp. 192–198, March–April, 2000. 相似文献
9.
Electron and x-ray diffraction studies on Al86Fe14, Al82Fe18 and Al75Fe25 quasicrystals 总被引:1,自引:0,他引:1
J A Sekhar T Rajasekharan P Rama Rao G Parthasarathy S Ramkumar E S R Gopal C S Lakshmi R M Mallya 《Pramana》1986,27(1-2):267-273
Electron and x-ray diffraction experiments on the metlt-spun Al100−x
Fe
x
(x=14, 18, 25) alloys are carried out. It is observed that all the melt-spun alloys possessing the quasi-crystalline phases
have icosahedral point-group symmetry.
The authors felicitate Prof. D S Kothari on his eightieth birthday and dedicate this paper to him on this occasion. 相似文献
10.
Mixed Li-Ni oxides, LixNi1-xO, are prepared by solid state reaction in the range 0.2≤x≤0.46 by annealing around 1000 K for various times. As reported
in literature, above x=0.31 an ordered solid solution (OSS) is formed in which planes of pure Ni alternate with Li-Ni planes,
whereas below x=0.2 only a fully disordered solid state solution (SSS) exists. We analyze the intermediate composition region
0.22≤x≤0.31 by fitting the X-ray patterns with a two-phases model using the Rietveld method: a SSS phase and an OSS phase
where partial occupancy of the Ni-planes by lithium is allowed. The two phases coexist in the intermediate region, and no
lithium is allowed in the Ni planes of the OSS phase; furthermore, the lithium contents of the OSS and SSS phases are approximately
x ∼ 0.4 and x ∼ 0.2, respectively, and loss of lithium is associated with transformation of the OSS phase into SSS.7Li NMR data find evidence of a common magnetic behaviour of the samples containing the OSS phase which agrees with the X-ray
findings.
Paper presented at the 2nd Euroconference on Solid State Ionics, Funchal, Madeira, Portugal, Sept. 10–16, 1995 相似文献
11.
Chun-Ming Wu Chi-Yen Li Yen-Ting Kuo Chin-Wei Wang Sheng-Yun Wu Wen-Hsien Li 《Journal of nanoparticle research》2010,12(1):177-185
We report on the direct observation of the intrinsic magnetization behavior of Mackay icosahedral Au nanoparticles. The spin
arrangements in 3.5-nm icosahedral Au particles are found to be ferrimagnetic-like, where the core and surface moments point
in opposite directions, with a net spontaneous magnetic moment of 16 μB per particle. The unpaired spins behave as J = 1/2 quantum spins. The average level separation is found to be a factor of ~1.53 larger than that estimated according to
the Kubo formula for spherical Au particles. This reflects the fact that there are considerably fewer atoms packed in a particle
with an icosahedral geometry than with a spherical one. 相似文献
12.
M. M. Markina K. V. Zakharov A. N. Vasil’ev I. Balasz I. Deac E. Burzo 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(2):190-192
The thermodynamic and magnetic properties of the La1 − x
Pb
x
MnO3 (0.24 ≤ x ≤ 0.40) solid solution system were investigated in the temperature range of 4.2–340 K. All objects were ferromagnetics with
Curie temperature T
C
≈ 320–340 K, which slowly increased with x. The M(T) behavior in the magnetic ordering region indicated a nonuniform ground state, due possibly to the competition of ferromagnetic
and antiferromagnetic interactions. The increase in the saturation magnetic moment with x can be described by a simple model of the binary bonds in La1 − x
Pb
x
MnO3. 相似文献
13.
D. V. Olenev É. I. Isaev Yu. Kh. Vekilov 《Journal of Experimental and Theoretical Physics》1998,86(3):550-558
Electron spectra and wave functions of icosahedral quasicrystals have been investigated in the tight-binding approximation
using the two-fragment structural model (the Amman-MacKay network) with “central” decoration. A quasicrystal has been considered
as a limiting structure in a set of optimal cubic approximants with increasing lattice constants. The method of level statistics
indicates that the energy spectrum of an icosahedral quasicrystal contains a singular (nonsmooth) component. The density of
electron states has been calculated for the first four optimal cubic approximants of the icosahedral quasicrystal, and the
respective Lebesgue measures of energy spectra of these approximants have been obtained. Unlike the case of a one-dimensional
quasiperiodic structure, the energy spectrum of an icosahedral quasicrystal does not contain a hierarchical gap structure
typical of the Cantor set of measure zero in a one-dimensional quasicrystal. Localization of wave functions in an icosahedral
quasicrystal has been studied, and their “critical” behavior has been detected. The effect of disorder due to substitutional
impurities on electron properties of icosahedral quasicrystals has been investigated. This disorder makes the electron spectrum
“smoother” and leads to a tendency to localization of wave functions.
Zh. éksp. Teor. Fiz. 113, 1009–1025 (March 1998) 相似文献
14.
N. Shramchenko F. Dénoyer 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(1):51-59
A detailed investigation of the Fourier space of several Al-Pd-Mn samples with composition Al-72.6 at. %, Pd-22.9 at. %, Mn-4.5
at. % is reported. In the phase diagram of the Al-Pd-Mn ternary alloy, this composition corresponds to the so-called ξ' phase which was described as an icosahedral quasicrystalline approximant. By re-examining the Fourier space by means of
X-ray diffraction (powder patterns and single crystal precession patterns), complex structures in close relation with the
ξ'-phase have been observed. These long-range order complex structures are described as resulting from a periodic perturbation
of the ξ' structure along the c direction. Two states with periodicities c
(3 + τ) and c
(5 + τ) have been observed in this study (τ: golden mean). Structural models based on periodic arrangements of “defects” layers separating layers of phase are proposed. These two states are certainly intermediate states between the phase and the metastable decagonal quasicrystalline phase.
Received 11 April 2002 / Received in final form 24 June 2002 Published online 17 September 2002 相似文献
15.
The infrared absorption spectra of 2,3- and 3,5-dichloroanilines have been recorded in the region 250–4000 cm−1. The spectra of the latter are recorded in solid phase (KBr and Nujol mull) and in CS2/CCl4 and CHCl3 solutions while that of the former in thin film only. The spectra have been analysed assuming C
3
and C2v
point group symmetry respectively and a tentative assignment of the observed bands to different fundamental modes has been
made. 相似文献
16.
This paper reports on the first results obtained from the investigation of the effect of IR radiation on the low-temperature
(1.8 ≤ T ≤ 4.2 K) plasticity of solid hydrogen. It has been found that, when the samples are exposed to IR radiation, a drastic increment
ΔɛIR of the elongation per unit length ɛ (which was preliminarily achieved under a continuously applied mechanical stress σ =
const) occurs without an increase in the temperature of the samples. It has been revealed that the effect observed both in
the case of normal hydrogen (n-H2, 75% o-H2) and in the case of parahydrogen (p-H2, ∼0.2% o-H2) only for a sufficiently high power of the IR radiation source has a threshold character. The reverse deformation of solid
hydrogen is observed after the irradiation with a flux of IR photons is completed: the quantity ɛ rapidly decreases to values
provided only by the applied load. The appearance of jumps in the increment of deformation ΔɛIR
i
is interpreted as a consequence of the existence of the fundamental IR absorption band for solid hydrogens. It has been established
that, depending on the time t of exposure of the samples to IR radiation, the change in the quantity ΔɛIR
i
(t) obeys the logarithmic law, which is characteristic of the dislocation creep and observed in the case of unirradiated hydrogen.
It has also been found that, under multiple relatively long-term exposure to IR radiation, the constant α of the logarithmic
creep of n-H2 abruptly decreases, whereas the strength of both the n-H2 and p-H2 samples increases significantly, which indicates their explicit hardening (instead of the expected “superplastic” behavior
due to the exposure to IR irradiation). 相似文献
17.
G. M. Abramova G. A. Petrakovskii D. A. Velikanov A. M. Vorotynov M. S. Molokeev Y. Mita V. V. Sokolov G. S. Patrin 《Physics of the Solid State》2012,54(2):293-297
The Cr
x
Mn1 − x
S single crystals have been synthesized based on manganese monosulfide as a result of cation substitution, and their magnetic
properties have been studied. It has been established that the Cr
x
Mn1 − x
S solid solutions with a face-centered cubic NaCl structure are formed in the concentration region 0 ≤ x < 0.3. The unit cell parameter of the solid solution decreases as the degree of substitution increases due to the variation
in the ionic radius of cations. These substances are antiferromagnets. An increase in the degree of cation substitution in
the Cr
x
Mn1 − x
S solid solutions is accompanied by a decrease in the number of 3d electrons in the d shell of manganese monosulfide and causes a decrease in the magnetic transition temperature from 149 K (x = 0) to 96 K (x = 0.29), which differs from previously known results. 相似文献
18.
V. M. Bystritsky A. Adamczak G. A. Beer M. Filipowicz M. C. Fujiwara T. M. Huber R. Jacot-Guillarmod P. Kammel S. K. Kim P. Knowles A. R. Kunselman M. Maier V. E. Markushin G. M. Marshall F. Mulhauser A. Olin C. Petitjean T. A. Porcelli V. A. Stolupin J. Woźniak J. Zmeskal 《Hyperfine Interactions》2001,138(1-4):47-53
We present the study of μp atom scattering in solid hydrogen. Anomalously large emission of E
pμ≤1.9 meV μp's from a solid H2 layer was observed for the first time. This three times greater μp atom yield is due to non-elastic phonon scattering. As a result, it becomes possible to generate an ultracold flux of μp atoms. The recent calculations of the total and differential cross sections agree with all experimental results of μp atom scattering in solid H2.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
N. M. Olekhnovich Yu. V. Radyush N. P. Vyshatko I. I. Moroz A. V. Pushkarev M. N. Palatnikov 《Physics of the Solid State》2005,47(4):703-709
The structural characteristics and dielectric properties (ε′, tanδ) of Li0.12Na0.88TayNb1−y
O3 solid solutions (y ≥ 0.7) synthesized under high or normal pressure (HP and NP ceramics, respectively) were studied. It was established that
these solid solutions have an orthorhombic perovskite structure (space group Pnma) in the paraelectric state. The temperature and frequency dependences of the dielectric properties of the solid solutions
are described in terms of microinhomogeneity of a system containing ferroelectric clusters with an enhanced Nb content as
compared to that in the matrix. The characteristics of the cluster system depend on the method by which the ceramics were
prepared. The HP ceramic is more homogeneous on the microscale. The permittivity ε′ was found to undergo thermal hysteresis
in the region from 200 to 400 K, the parameters of which strongly differ for the HP and NP ceramics. The temperature of the
maximum ε′ obtained in cooling runs for the NP and HP ceramics is 50–60 and 110 K lower, respectively, than that on the heating
branch. The hysteresis may originate from interaction of the antipolar mode condensing under cooling with nonpolar ordered
distortions, which drives the system to the state of global minimum. When the system residing in this state is heated, this
mode undergoes decondensation at a higher temperature.
__________
Translated from Fizika Tverdogo Tela, Vol. 47, No. 4, 2005, pp. 679–685.
Original Russian Text Copyright ? 2005 by Olekhnovich, Radyush, Vyshatko, Moroz, Pushkarev, Palatnikov. 相似文献
20.
D. V. Shamshur S. A. Nemov R. V. Parfenev M. S. Kononchuk V. I. Nizhankovskii 《Physics of the Solid State》2008,50(11):2028-2032
The temperature dependences of the conductivity and the Hall effect in heavily doped polycrystalline samples of the (Pb
z
Sn1 − z
)0.84In0.16Te solid solutions with lead content varied within the 0 ≤ z ≤ 0.9 interval have been studied. For x ≤ 0.65, the material undergoes a superconducting transition at a critical temperature T
c
≤ 4.2 K in a magnetic field H
c2(0 K) ∼ 50 kOe. As the lead concentration is increased to z ≤ 0.9, a clearly pronounced trend to transfer of the material to the dielectric state is observed at helium temperatures.
The observed behavior is related to the variation in the band structure of the solid solutions with variations in the material
composition, doping level, and position of the indium impurity band. The dependences of the resistivity, Hall effect, and
superconducting characteristics of (Pb
z
Sn1 − z
)0.84In0.16Te on the temperature and the composition of the solid solutions is observed to be related to the variation in its band structure
as tin atoms are replaced with lead in the metallic sublattice of the compound.
Original Russian Text ? D.V. Shamshur, S.A. Nemov, R.V. Parfen’ev, M.S. Kononchuk, V.I. Nizhankovskii, 2008, published in
Fizika Tverdogo Tela, 2008, Vol. 50, No. 11, pp. 1948–1952. 相似文献