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1.
I. Antoniou M. Gadella J. Mateo G.P. Pronko 《International Journal of Theoretical Physics》2003,42(10):2389-2402
Through two examples: the Friedrichs model and a particular case of central potential scattering, we illustrate the way of constructing Gamow vectors. 相似文献
2.
Applied Biochemistry and Biotechnology - 相似文献
3.
The question about the definition of the “internal pressure” concept is being discussed. It is shown that the previously found differential relation between the cohesion energy density and the internal pressure is one of the examples of an absolutely general interrelation between definitely connected differential functions. It is ascertained that the ratio (the internal pressure divided by the cohesion energy density) is a structuresensitive parameter inherent to the calorific (thermal) equation of a liquid state. 相似文献
4.
M. Stenger S. Baumhoff J.-Y. Prieur J. Joffrin J.-P. Contour 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,2(2):177-182
We present measurements of the attenuation and phase velocity of surface acoustic waves in thin YBa2Cu3O films as a function of temperature, in magnetic fields up to 3.6 T applied parallel to the c-axis of the films. We have observed anomalies in both, the attenuation and the phase velocity in the vicinity of the superconducting
critical temperature which do not depend on the magnetic field. Possible origins of these anomalies, observed, to our knowledge,
for the first time in YBa2Cu3O thin films, are discussed and compared to bulk acoustic wave experiments. We present a kind of feedback technique for surface
acoustic waves which improves the sensitivity of this type of measurement. The actual sensitivity limits are mentioned.
Received: 7 August 1997 / Revised: 7 November 1997 / Accepted: 17 November 1997 相似文献
5.
The influence of internal excitation on the reactions of O
2
+
+ CH4 and of CO
2
+
+ NO has been investigated using a slow flow drift tube. The rate coefficients for these reactions obtained as a function of relative kinetic energy in various buffer gases like He, Ne, Ar, and Kr showed higher values under conditions where the internal excitation of the reactant ions was enhanced. For both reactions the lowest reactivity at all kinetic energies was observed to occur in He, indicating that He is the least effective buffer for collisionally inducing internal excitation of molecular ions. 相似文献
6.
The molecular and electronic structure of the ground state of peroxyacetyl nitrate (PAN) was calculated by the unrestricted
Hartree-Fock-Roothaan method with the use of the standard 3–21G and 6–31G basis set. The potential curve of the internal rotation
about the peroxide bond of PAN was calculated with the 6–31G basis set. The curve contains two maxima. The ground state of
PAN is characterized by a structure in which groups of atoms adjacent to the peroxide bond lie in planes that are perpendicular
to each other (the dihedral angle ϱ(COON) is 89.9°). The calculated barriers to rotation are 19.6 and 66.8 kJ mol−1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 600–604, April, 1998. 相似文献
7.
UV absorption spectra of acetyl fluoride-h3 and -d3 (CH3COF and CD3COF) molecules in the region of S1S0 electronic transitions are investigated. The origins (00
0 or 140±
0) of these transitions are observed at 39912 and 39904 cm–1, respectively, and some of the fundamental frequencies of these molecules in the s0 and S1 states are determined. In particular, the systems of torsion and inversion (out-of-plane C=O vibrations) energy levels are studied. The geometric parameters of an acetyl fluoride-h3 molecule in the S1 state are estimated by the theoretical simulation of the rotational contours of the 00
0 (140±
0) band. These data are used to evaluate the potential barriers to internal rotation in the S0 and S1 states, which were found to be 360 and 560 cm–1 for acetyl fluoride-h3 and 380 and 770 cm–1 for acetyl fluoride-d3, respectively, as well as the potential barriers to inversion in the S1 states, which were found to be 2090 and 2370 cm–1 for acetyl fluoride-h3 and acetyl fluoride-d3, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1957–1964, November, 1994.In conclusion, the authors would like to acknowledge T. S. Kuznetsova for the synthesis and purification of the AF samples.The research presented here was supported in part by the International Science Foundation under grant No. MJ 1000. 相似文献
8.
《Arabian Journal of Chemistry》2020,13(12):8848-8887
Phthalocyanine (Pc) complexes are an important class of dyes with numerous (e.g., biological, photophysical, and analytical) applications. Among the methods used to improve the properties of these complexes, one should mention the introduction of different substituents, variation of the central metal ion, ligand exchange, and conjugation to nanomaterials (e.g., carbon-based nanomaterials and metal nanoparticles (NPs)). This work briefly reviews Pc complex conjugation to Ag and Au NPs, highlights the different NP shapes, and discusses the diversity of conjugation approaches. Moreover, the use of UV–Vis spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, atomic force microscopy, dynamic light scattering and Fourier transform infrared spectroscopy to characterize Pc-NP hybrids is summarized. The effect of conjugation on Pc photo-physicochemical properties (fluorescence, singlet oxygen generation, triplet state formation, and optical limiting behavior) is discussed, and future perspectives for the synthesis and applications of new hybrids are provided. 相似文献
9.
In this paper, calculating the molecular internal rotating steric factor of polymers by the radiation crosslinking method is studied and a relationship between the molecular internal rotating steric factor (σ) and crosslinking parameter βis established~([1]) by taking account of the effect of polymer chain flexibility on βvalue, σvalue of polymer obtained by this method is in agreement with that given with other method. 相似文献
10.
化学镀广泛应用于非金属的电镀、电铸前的施加导电层。化学镀沉积层质量与其在零件上的附着力有着密切的关系 ,重视对化学镀沉积层内应力的研究 ,开发一个低温、低内应力的化学镀镍工艺 ,对于化学镀沉积层的推广应用有着十分重要的意义。本文采用正交实验方法对低温、低内应力化学镀镍工艺进行了系统研究 ,开发出了一个低温、低内应力的化学镀镍工艺。在实验过程中发现沉积层内应力同其在零件上的结合力具有密切关系并对其进行了初步探讨。1 实验方法1 1 正交实验根据探索性实验结果分析 ,影响化学镀镍层内应力σ和沉积层速率r的主要因… 相似文献