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1.
The radial distribution function can be expressed in a virial expansion. Using the 6 : 12 potential the second-order density coefficient, g 2(r), is numerically calculated for a wide range of temperatures and intermolecular separations. These results are used to calculate the second-order density coefficient, c 2(r), in the expansion of the direct correlation function and to calculate the fourth virial coefficient, B 4. In addition, approximate results for g 2(r), c 2(r), and B 4 are calculated on the basis of the Percus-Yevick, hypernetted chain, and the self-consistent approximations of Hurst and Rowlinson. These approximate results are compared with the exact results. The Percus-Yevick theory is in good agreement with the exact results at high temperatures but is unsatisfactory at low temperatures. The hyper-netted-chain approximation is in fair agreement with the exact results at high temperatures, is in poor agreement at intermediate temperatures, but is in good agreement at low temperatures. The self-consistent approximations are in reasonably good agreement with the exact calculations at all temperatures.  相似文献   

2.
The preliminary results on the angular distributions of the vector A y and tensor A yy , A xx analyzing powers in dp elastic scattering at T d = 880MeV are presented. A region of center-of-mass system angles from 60° to 140° is covered. The experimental data are compared with the preliminary calculations obtained within framework of different theoretical approaches. The experiment has been performed at the Internal Target Station at Nuclotron within the framework of the program on the study of light nuclei spin structure proposed at JINR (Russia) and RIBF (Japan).  相似文献   

3.
Experimental results on intensities and band shapes of collision-induced Raman scattering at the v 2 and v 3 vibrational transitions in gaseous and liquid CO2 are reported and discussed. The CO2 results are compared with new data for v 3 in SF6.  相似文献   

4.
The exchange-correlation part (xc) to the free energy is numerical evaluated in the RPA at arbitrary degree of degeneracy. The results are compared with numerical data of easy-to-use analytic fit-formulas or Padé approximants of the xc-term. All together results show very high accuracy at extremly high densities (rs ≈ 1). The agreements disappear between the several formulas for increasing Brueckner parameter rs. Numerical results for the xc-potentials (pressure and chemical potential) at finite temperatures for an electron-ion system are given. The xc-part of the ground state energy of our electron-ion model is compared with the ground state energy for metallic hydrogen and with Monte-Carlo calculations.  相似文献   

5.
The present paper reports the reactivity between TiO2 and oxygen and the related charge transfer at 298 and 1,073 K. The studies were performed using work function measurements. It was found that oxidation of TiO2 at 1,073 K and p(O2) = 75 kPa, initially standardized at 1,173 K and p(O2) = 10 Pa, results in work function changes that are consistent with the theoretical model of the charge transfer during oxygen chemisorption and oxygen incorporation at the absence of structural transitions. However, oxidation of TiO2 at 298 K, p(O2) = 75 kPa, which has been initially standardized at 1,173 K in extremely reducing conditions at p(O2) = ∼10−10 Pa, results in work function changes that are consistent with low-dimensional structural changes of the surface layer. It is shown that oxidation of strongly reduced TiO2 at 298 K results in a decrease of work function, which cannot be explained without assuming the structural changes of the outermost surface layer.  相似文献   

6.
The influence of sulphidation on the metallic phase in a series of Fe100–x Cr x alloys (x<15) was investigated by means of57Fe Mössbauer spectroscopy. The results obtained gave evidence that the sulphidation at 1073 K is selective in the atmosphere of H2/H2S, with the partial pressure of sulphur ranging from 10–7 to 10–9 atm. Atx cr=5.0(1) at.%, a change of the sulphidation preference occurs. Forx<5.0 at.%, the sulphidation results in an enrichment of the metallic phase in chromium, while forx> 5.0 at.%, in iron.  相似文献   

7.
The tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 4.5 GeV/c on beryllium at an angle of 80 mr in the vicinity of baryonic resonances excitation have been measured. The Ayy data being in good agreement with the previous results obtained at a zero angle demonstrate an approximate t scaling up to - 0.9 (GeV/c)2. The results of the experiment are compared with the predictions of the multiple-scattering and -meson exchange models. Received: 20 April 2000 / Accepted: 29 May 2000  相似文献   

8.
The fidelities of the Kondo and the Friedel-Anderson (FA) impurities are calculated numerically. The ground states of both systems are calculated with the FAIR (Friedel artificially inserted resonance) theory. The ground state in the interacting systems is compared with a nullstate in which the interaction is zero. The different multi-electron states are expressed in terms of Wilson states. The use of N Wilson states simulates the use of a large effective number N eff of states. A plot of ln(F) versus N ∝ ln(N eff ) reveals whether one has an Anderson orthogonality catastrophe at zero energy. The results are at first glance surprising. The ln(F) – ln(N eff ) plot for the Kondo impurity diverges for large N eff . On the other hand, the corresponding plot for the symmetric FA impurity saturates for large N eff when the level spacing at the Fermi level is of the order of the singlet-triplet excitation energy. The behavior of the fidelity allows one to determine the phase shift of the electron states in this regime.  相似文献   

9.
Detailed magnetization measurements up toH=6T have been performed on a powdered specimen of the weak ferromagnet NiCO3 in the temperature rangeT c <T<4T c . Starting atT=1.15T c , an excellent agreement is found at all temperatures between the experimental values of the magnetization and those calculated up toH 3 terms in an extension ofDzyaloshinsky's theory of weak ferromagnetism. Both isotropic and antisymmetrical exchange constants are determined and found in good agreement with previous low temperature magnetization results. These results indicate that at allT>1.15T c , the molecular field approximation satisfactorily describes the magnetic properties of NiCO3.  相似文献   

10.
The space-time structure at hadronization was studied within new EPOS model using femtoscopical methods. The results of the study was compared with the STAR HBT data for AuAu collision and first ALICE HBT data for pp collisions. The model predicted mT and centrality dependence of R out, R side and R long femtoscopy parameters were found to be in accordance with the STAR data.  相似文献   

11.

We report the results of the measurement of T-violating transverse muon polarization in the decays K +μ + ν μ π 0 (K μ3) and K +μ + ν μ γ(K μ2γ) performed in experiment E246 at KEK. The preliminary results obtained for the entire data set taken in the period 1996–2000 are consistent with no T violation in both decays.

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12.
The analysing power AN is examined in the range of the Coulomb-hadron interference on the basis of the experimental data from pL = 6 GeV/c up to 200 GeV/c taking account of a phenomenological analysis at pL = 6 GeV/c and a dynamic high-energy spin model. The results are compared with the new RHIC data at pL = 100 GeV/c. The new experimental data obtained at RHIC indicate small contributions of the hadron spin-flip amplitude.  相似文献   

13.
Ball  J.  Chesny  Ph.  Combet  M.  Fontaine  J. M.  Kunne  R.  Lemaire  M. C.  Sans  J. L.  Bystricky  J.  Lac  C. D.  Lehar  F.  de Lesquen  A.  de Mali  M.  Perrot-Kunne  F.  van Rossum  L.  Bach  P.  Demierre  Ph.  Gaillard  G.  Hess  R.  Rapin  D.  Sormani  Ph.  Goudour  J. P.  Binz  R.  Klett  A.  Peschina-Klett  R.  Rössle  E.  Schmitt  H.  Barabash  L. S.  Janout  Z.  Khachaturov  B. A.  Usov  Yu. A.  Lopiano  D.  Spinka  H. 《Zeitschrift fur Physik C Particles and Fields》1994,61(4):579-585

We present data of several rescattering observables measured inn p elastic scattering between 0.80 and 1.10 GeV. The SATURNE II polarized beam of free neutrons obtained from the break-up of polarized deuterons was scattered on the Saclay polarized frozen-spin proton target. Three different configurations of beam and target polarization directions were used: the observablesD onon andK onno were measured with the normal-normal spin configuration at eight energies;N onkk ,D os″ok andK os″ko were determined with the longitudinal-longitudinal configuration at six energies;N onsk ,D os″ok andK os″so with the sideway-longitudinal configuration at six energies. Part of the data was obtained with an unpolarized CH2 target where only the two spin-index polarization transfer parametersK os″ko andK os″so were determined. Data are compared with phase shift analyses predictions and with the LAMPF results at 0.788 GeV. Present results are the first measurements of rescattering observables above 0.80 GeV. They provide an important contribution to any future theoretical or phenomenological analysis.

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14.
The border luminance of the test stimulus between the natural and unnatural object color, yynBu was obtained for different spatial sizes of the immediate surround to prove that nBu can be determined based on a new recognized visual space of illumination (RVSI) that is assumed to be constructed for the immediate surround separately from the RVSI for the subjects room itself. The nBu of five test stimuli were determined for six different sizes covering from zero to 1866 cm2 with four different lightnesses, N4, N6 and N8, while keeping the room illuminance constant at 100 or 600 lx. The results showed that luminance of the border nBu gradually decreased as the size of the immediate surround was increased and that the decrease was larger for immediate surround with lower lightness. The results were interpreted as showing a new RVSI constructed for the spatial extent of the immediate surround of the test stimulus, and the RVSI was more completely constructed for larger spatial size of the immediate surround. © 2005 The Optical Society of Japan  相似文献   

15.
In connection with the problem of identifying magnetic states in the vicinity of x 0 (the multicritical point of the x-T diagrams of spin-glass systems) a study has been made of properties that can be exploited to determine the presence of a thermodynamic phase transition at the Curie point T C and the distinctive features of the transition, specifically, the temperature dependence of the magnetic part of the specific heat C m(T), the temperature dependence of the low-field magnetization σ H(T), and (with a view toward examining critical behavior in a magnetic field) the magnetization isotherms σ H(T). The investigated object is the system of dilute ferrimagnetic spinels Li0.5Fe2.5−x GaxO4, in which every type of magnetic state has spatially inhomogeneous cluster structures. The results obtained for a sample with x=1.45 indicate that the classical criteria of a ferrimagnetic second-order phase transition at T C=(97±2) K occur for xx 0. The results of similar investigations for a sample with x=1.6, which exists in the cluster spin-glass state for T<T f=22 K and in an uncorrelated cluster state of the superparamagnetic type for T>T f, are also given for comparison with the preceding case. Zh. éksp. Teor. Fiz. 114, 2065–2077 (December 1998)  相似文献   

16.
The interaction of an amino-functionalized ionic liquid, 1-(2-aminoethyl)-3-butylimidazolium bromide ([NH2C2C4im]Br), with cytochrome c (cyt c) at pH 7.4 was investigated using fluorescence and UV-Vis absorption spectroscopic techniques. From the experimental results, it is found that cyt c has a strong ability to quench the intrinsic fluorescence of [NH2C2C4im]Br and the quenching mechanism is considered as a static quenching process. The binding constants and the number of binding sites (n) were calculated at different temperatures. The thermodynamic parameters such as free energy change (ΔG), enthalpy change (ΔH), and entropy change (ΔS) were calculated by thermodynamic equations. According to the results, the values of ΔG, ΔH, and ΔS are all negative, suggesting that interaction between [NH2C2C4im]Br and cyt c is spontaneous and mainly driven by hydrogen bonding and van der Waals forces.  相似文献   

17.
采用PR650光谱光度计对高速沉积微晶硅薄膜的生长过程进行了在线监测研究,并对所对应的材料进行了Raman谱和红外吸收谱(FTIR)的测试.结果表明:能反映材料晶化程度的I[SiH*/I[Hβ*比值在沉积时间为100 s之内有下降的趋势,且反应气体总流量Tfl越小下降趋势越明显,这与拉曼散射光谱对材料的结构测试结果一致;沉积5 min时I 关键词: 高速沉积 微晶硅薄膜 电子温度  相似文献   

18.
K D Abhyankar 《Pramana》1974,2(6):336-340
From the radial velocity data for O-B5 stars within 3 kpc of the Sun the variation of the semi-axesΣ 1 andΣ 2 of the velocity ellipsoid in the solar region is estimated. It is found that both the semi-axes as well as their ratioΣ 2/Σ 1 decrease away from the galactic centre. The value ofΣ 2/Σ 1 changes from 1.17 atR=9 kpc to 0.48 atR=11 kpc passing through a value of 0.86 at the solar distance ofR 0=10 kpc. These results are consistent with the usually assumed inverse square law of force in the outer regions of the galaxy.  相似文献   

19.
In this paper, we extended our work (Abu-Shady, Int. J. Theory Phys. 49:2425, 2010) to include nucleon properties. The field equations have been solved in the mean-field approximation using the effective mesonic potential at finite temperature. We found that the nucleon first mass increases up to \frac45 Tc\frac{4}{5} T_{c} MeV (where T c is the critical point temperature) then decreases at higher values of temperature which approach the critical temperature (T c ). In addition, we found that the magnetic moments of the proton and neutron can be increased by increasing the temperature up to the critical temperature. Moreover, we examined the axial coupling constant g A (0), and the pion-nucleon coupling constant g πNN (0) as functions of temperature. The obtained results are compared with previous works. From the results, we conclude that finite temperature plays a significant role in the change of behavior of nucleon properties.  相似文献   

20.
在室温下,采用射频磁控溅射法制备了Cu/TiOx纳米晶复合薄膜.利用X射线粉末衍射(XRD)、X射线光电子能谱(XPS)对其结构进行表征,并研究了Cu/TiOx复合薄膜的UV-vis吸收谱和亲水性.结果表明,退火前后薄膜中钛元素皆以Ti3+形式存在.薄膜在可见区有吸收,吸收限为600 nm左右.Cu/TiOx复合薄膜具有良好的亲水性.这主要是由于Cu的掺杂,使得薄膜的性能的亲水性变好. 关键词x复合薄膜')" href="#">Cu/TiOx复合薄膜 射频磁控溅射 XPS 亲水性  相似文献   

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