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1.
We give a noncommutative version of the complex projective space 2 and show that scalar QFT on this space is free of UV divergencies. The tools necessary to investigate quantum fields on this fuzzy 2 are developed and several possibilities to introduce spinors and Dirac operators are discussed.  相似文献   

2.
A misunderstanding persists between Stuart and me, which I do my best to clarify. Bayesian inverse subjectivities versus relativistic covariance and physical intersubjectivity are discussed. A joint number of chances formalism taking care of the propagation of the probability of causes is proposed.  相似文献   

3.
From analysis of anisotropical lattice bands properties of 50 reflection spectra both of the CO stretching and bending bands measured from some pearl (Ca++CO 3 –– or Ca++HCO 3 –– layer) we discussed following subjects.i) Quantized properties present both in reflectivity and in energy. ii) classifications of the Optical Activity. iii) Polar distributions of the CO3 oscillators in Ca++CO 3 –– surface mono-layer. iv) Force constants of these oscillators. v) Step variation of the dipolemoment and their influences to the degree of Optical Activity. vi) Two types of hysteresis loops of the values of YN (M2Jbend ()/M1Jstret. ()) derived from the oscillators which are at innert-state, at weak active-state and at active-state.  相似文献   

4.
For the first time, the antiStokes luminescence in colloidal solutions of CdTe nanocrystals on excitation below the absorption edge has been discovered. The maximum spectral shift to the shortwave region relative to the excitation energy E con max = 319 meV is obtained for meansized nanocrystals (2.5 nm). The conversion efficiency of the absorbed radiant energy is 1.3·10–2%. The rise in the antiStokes photoluminescence intensity with increasing temperature and the linear dependence on the exciting radiation intensity have been established. It is shown that the effect observed cannot be caused by twophoton excitation or by Auger recombination. It is assumed that the basic mechanism of the luminescence observed is the radiative recombination through the energy levels of the states attributable to the disturbance of the crystal structure in the nanocrystals.  相似文献   

5.
Using methods of emission spectroscopy, we have determined the gaskinetic temperature fields of planar highfrequency capacitive discharge plasma in N2/CO2/He gas mixtures depending on the excitation frequency, discharge current, pressure, and chemical composition of the mixture. It is shown that the dominant contribution to the neutral component heating in the center of the discharge chamber is made by the processes of VT relaxation of vibrationally excited molecules N2(X 1, V) and CO2(X 1, V), whereas in the zones near the electrodes an important role in the heating is played, along with the VT relaxation of the N2(X 1, V) and CO2(X 1, V) molecules, by the processes of deactivation of the metastable states A 3 of the N2 molecule.  相似文献   

6.
7.
A method is suggested for the derivation of finite-size corrections in the thermodynamic functions of systems with pair interaction potential decaying at large distancesr asr d , whered is the space dimensionality and>0. It allows for a unified treatment of short-range (=2) and long-range (<2) interaction. The asymptotic analysis is illustrated by the mean spherical model of general geometryL d–d× d subject to periodic boundary conditions. The Fisher-Privman equation of state is generalized to arbitrary real values ofd, 0d. It is shown that the-expansion may be used to study the breakdown of standard finite-size scaling at the borderline dimensionalities.  相似文献   

8.
The high resolution Stark spectra of the singly deuterated methanol isotope, CH3OD, have been studied using the HCN laser with Stark fields up to approximately 60 000 V/cm. Numerous families of absorption lines have been observed in both parallel and perpendicular polarizations, resulting in the following assignments: with the 311 m line – J K = 181 180 E 2, t = 1; and with the 337 m line – J k = 64 53 E 2, t = 0 and J K = 146 135 A, t = 1. Zero-field frequencies for the assigned transitions are in agreement with Fourier transform measurements and those calculated from the available molecular constants.  相似文献   

9.
The --decay of 147Cs to 147Ba has been studied by means of - and X-ray spectroscopy. A new level scheme of 147Ba is significantly modified and extended in comparison to the one previously reported. The Advanced Time-Delayed (t) method has been applied to measure half-lives of the 46.2 and 85.4 keV levels in 147Ba yielding T1/2 of 510(80) ps and 370(100) ps, respectively. The lifetime results combined with the deduced internal conversion coefficients allowed to assign M1 multipolarity to three transitions. The B(M1) values obtained for the 39.2, 46.2 and 85.4 keV transitions range from 0.017 to 0.043 W.u. and represent typical B(M1) strength in the Ba-Er region. Model calculations using a shell correction approach with the axially deformed Woods-Saxon potential predict for 147Ba an octupole deformed ground state with 3 = 0.11.  相似文献   

10.
The multiplicities a of simple modules L in the composition series of Kac modules V lambda for the Lie superalgebra (m/n ) were described by Serganova, leading to her solution of the character problem for (m/n ). In Serganova's algorithm all with nonzero a are determined for a given this algorithm, turns out to be rather complicated. In this Letter, a simple rule is conjectured to find all nonzero a for any given weight . In particular, we claim that for an r-fold atypical weight there are 2r distinct weights such that a = 1, and a = 0 for all other weights . Some related properties on the multiplicities a are proved, and arguments in favour of our main conjecture are given. Finally, an extension of the conjecture describing the inverse of the matrix of Kazhdan–Lusztig polynomials is discussed.  相似文献   

11.
Einstein's field equations with variablegravitational coupling G = G(t) and decaying vacuumenergy density = (t) are considered asdescribing matter creation in a cosmological framework.The particle creation rate is determined by thevariation rate of both G and . By consideringsimple phenomenological evolution laws for G and Lambda,an exact solution of the gravitational field equationsfor a flat Friedmann-Robertson-Walker (FRW)space-time is obtained leading to a self-consistentcosmological model describing matter and entropygeneration in the very early Universe.  相似文献   

12.
IR integrated photonic amplifiers at 1.55m operation will have good foreground in optical phasedarray radars for splitters and signal processing. The saturation gain characteristics of IR integrated photonic waveguide amplifiers (taken Er3+Yb3+ co-doped phosphate glass waveguide amplifiers as an example) are studied theoretically. For the homemade laser glass materials the calculated saturation intensities are 2.22kw /cm2 for signal and 10.15kw/cm2 for pump. The effects of absorption saturation of signal and pump lights on the gain of amplifiers are discussed.  相似文献   

13.
Finite squareL×L Ising lattices with ferromagnetic nearest neighbor interaction are simulated using the Swendsen-Wang cluster algorithm. Both thermal properties (internal energyU, specific heatC, magnetization |M|, susceptibility) and percolation cluster properties relating to the physical clusters, namely the Fortuin-Kasteleyn clusters (percolation probability P , percolation susceptibility p, cluster size distributionn l) are evaluated, paying particular attention to finite-size effects. It is shown that thermal properties can be expressed entirely in terms of cluster properties, P being identical to |M| in the thermodynamic limit, while finite-size corrections differ. In contrast, p differs from even in the thermodynamic limit, since a fluctuation in the size of the percolating net contributes to, but not to p. NearT c the cluster size distribution has the scaling properties as hypothesized by earlier phenomenological theories. We also present a generalization of the Swendsen-Wang algorithm allowing one to cross over continuously to the Glauber dynamics.  相似文献   

14.
In order to indentity the corrosion products formed on steel surfaces from 57Fe Mössbauer spectroscopy, detailed Mössbauer parameters have been determined for various kinds of iron-oxyhydroxides: -FeOOH, -FeOOH, -FeOOH and -FeOOH. 57Fe Mössbauer measurements of the iron oxyhydroxides indicate the following results. Fe occupies a single site in -FeOOH, but below the Néel temperature as at e.g., 300 K the Mössbauer spectrum is always broad, showing a distribution of the strength of the magnetic exchange interactions. Its shape depends on the grain-size and synthetic methods of the specimen. Fe occupies 3 sites in -FeOOH. High-purity reagents of -FeOOH always contain small amounts of -FeOOH and their Néel temperatures depend on the synthetic methods of the specimen. Mössbauer spectroscopy of the synthetic -FeOOH shows very broad distribution of the hyperfine magnetic fields.  相似文献   

15.
The correlation function and the correlation length are discussed in the theoretical framework of the Wilson-Feynman diagram expansion for small =4–d. It is shown explicitly that to order 2 the scaling relation = (2–) is satisfied and that the correlation function is a homogeneous function ofk and . The explicit form of the scaled correlation function is exhibited.  相似文献   

16.
Zusammenfassung Der Einflu\ von Mikrosegregations-Substrukturen auf das plastische Verhalten von Zinkeinkristallen entspricht den allgemeinen Erwartungen in der Weise, da\ die kritische Schubspannung mit wachsender Substrukturendichte zunimmt. Der Verfestigungskoeffizient A nimmt hingegen mit wachsender Substrukturendichte ab. Dabei wird der Verfestigungskoeffizient vom Charakter der Substruktur viel empfindlicher beeinflu\t als die kritische Schubspannung. Es wird angenommen, da\ dieser Einflu\ durch unterschiedlichen Fremdstoffgehalt zustande kommt.
, . , A . , . , .


Die Autoren danken Herrn Prof. M. Valouch, der die Durchführung dieser Arbeit ermöglicht hat. Herrn P. Kratochvíl sei an dieser Stelle für zahlreiche Diskussionen aufs herzlichste gedankt.  相似文献   

17.
The low-lying levels in 127La have been studied through the -decay of 127Ce ( T1/2 = 29s) produced by bombarding a natMo target with a 185-MeV 35Cl beam. Reaction products were on-line mass-separated, and -ray singles and - coincidence measurements were performed. Conversion electrons were also measured and multipolarities of transitions have been derived. The half-life of the 210.9-keV level was determined to be (1.9±0.3)ns by the - delayed coincidence technique. The level scheme obtained has been compared with calculations based on the Nilsson model.  相似文献   

18.
The spectroscopic properties of Cr2+ ions in Cr:Cd1–x Mn x Te (CMT) crystals are studied, and the possibility of using these impurity crystals as active media and saturable absorbers of solidstate lasers of medium IR range is demonstrated. The bands of absorption with a maximum at 1.9 m and of luminescence with a maximum at 2.6 m correspond to the transitions between the levels 5 T 2 and 5 E of the tetracoordinated Cr2+ ions with more than 1·10–18cm2 cross sections. The pulsed and continuous lasing modes of a Cr:CMT laser are realized in the 2.6m region. The Cr:CMT crystals are characterized by effective saturation of impurity absorption. The cross sections of absorption from the ground and excited states of the Cr2+ ions at = 2.09 m are determined: gsa = 1.1·10–18 cm2; esa/gsa < 0.1. With the use of the Cr:CMT crystals as a passive gate the regime of Qswitching of the Cr,Tm,Ho:YAG laser emitting at = 2.09 m is obtained.  相似文献   

19.
CdSb single crystals were prepared by zone melting in a boat both with and without a seed crystal in a stream of pure hydrogen or in a sealed and evacuated tube. The zone moved with a velocity of 1–20 cm/hour. Zone melting in an evacuated tube was used to prepare CdSb single crystals of high purity containing 1015 acceptors/cm3 at room temperature. During zone refining the stoichiometry is damaged; the front part of the ingot is enriched by cadmium and the end of the ingot by antimony; the enrichment is of an order of several percent after 10 passages of the zone. In the middle part of the ingot the stoichiometric compound remains unchanged. CdSb single crystals grow even by directional cooling of the melt of the stoichiometric compound without a seed crystal.
CdSb CdSb
CdSb 1–20 cm/, . CdSb CdSb , 1015 cm3 . ; , . . . CdSb .


The author died 28. 5. 1961.  相似文献   

20.
It is established that a fairly intense luminescence of thulium can be observed in solutions (suspensions of residues) of different-ligand complexes that include -diketone and an organic base. The luminescence characteristics of Tm compounds are determined in the series of acetyl acetone derivatives with different substituents, including fluorinated ones, of different length and structure. A relationship is found between I, , and of the Tm complexes and the character of the substituents in a -diketone molecule.  相似文献   

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