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1.
L. I. Ryabinkina O. B. Romanova S. S. Aplesnin 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(8):1050-1052
Electronic transitions of the metal-insulator type and magnetic transitions of the antiferromagnetic semiconductor-ferromagnetic
metal type are established in cation-substituted manganese sulfides Me
x
Mn1 − x
S (Me = Cr, Fe, V, Co), synthesized on the basis of MnS. The effect of negative colossal magnetoresistance is found and the regularities
of change in the conductivity type and magnetic order are analyzed.
Original Russian Text ? L.I. Ryabinkina, O.B. Romanova, S.S. Aplesnin, 2008, published in Izvestiya Rossiiskoi Akademii Nauk.
Seriya Fizicheskaya, 2008, Vol. 72, No. 8, pp. 1115–1117. 相似文献
2.
Zhi-Gang Luo Xiao-Lin Chen Xiang Liu Shi-Lin Zhu 《The European Physical Journal C - Particles and Fields》2009,60(3):403-411
Stimulated by recent observations of the excited bottom–strange mesons B
s1 and B
s2*, we calculate the semileptonic decays
, which is relevant for the exploration of the potential of searching these semileptonic decays in experiment. 相似文献
3.
The results of phenomenological partial-wave analysis of angular distributions for the process γp → νp measured at the Tohoku University (Japan) and model-independent estimates of Breit-Wigner parameters of S
11(1535) and S
11(1650) nucleon resonances obtained based on these data are presented.
Original Russian Text ? E.V. Balandina, E.M. Leikin, N.P. Yudin, 2009, published in Vestnik Moskovskogo Universiteta. Fizika,
2009, No. 1, pp. 87–89. 相似文献
4.
5.
We present a set of formulas using the solution of the QCD Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equation
to extract of the exponents of the gluon distribution, λ
g
, and structure function, λ
S
, from the Regge-like behavior at low x. The exponents are found to be independent of x and to increase linearly with lnQ
2 and are compared with the most data from the H1 Collaboration. We also calculated the structure function F
2(x,Q
2) and the gluon distribution G(x,Q
2) at low x assuming the Regge-like behavior of the gluon distribution function at this limit and compared them with an NLO-QCD fit to
theH1 data, two-Pomeron fit, multipole Pomeron exchange fit, and MRST (A.D. Martin, R.G. Roberts, W.J. Stirling, and R.S.
Thorne), DL (A. Donnachie and P.V. Landshoff), and NLO GRV (M. Glük, E. Reya, and A. Vogt) fit results.
The text was submitted by the authors in English. 相似文献
6.
V. N. Bocharov A. P. Burtsev E. V. Dubrovskaya T. D. Kolomiitsova D. N. Shchepkin 《Optics and Spectroscopy》2010,108(4):533-543
IR spectra of the solution of SF6 molecules in liquid NF3 at 84 K have been recorded. In a solvent transmission window of 1500–1750 cm−1, two wide absorption bands with pronounced peaks in the high-frequency part are observed. The profile of these bands is explained
by the influence of the resonance dipole-dipole (RDD) interaction of the states of the simultaneous transition ν1(SF6) + ν3(NF3) and ν2(SF6) + ν3(NF3) with the states (ν1 + ν3) and (ν2 + ν3) of the SF6 molecules, respectively. The use of three isotopic modifications 32SF6, 33SF6, and 34SF6 has allowed us to vary the resonance detuning and thus to change the strength of the RDD interaction. With the liquid near
the melting point being represented as a close-packed cubic crystal, the profile was calculated and its spectral characteristics
were determined. The frequencies of the main peaks coincide with the experimental values accurate to the error. 相似文献
7.
L.H. CoudertP. Çarçabal M. ChevalierM. Broquier M. HeppM. Herman 《Journal of Molecular Spectroscopy》2002,212(2):203-207
The ν6, ν17, and ν21 fundamental bands of dimethyl ether have been assigned and rotationally analyzed. The spectra used were recorded at 0.005 cm−1 spectral resolution with a Fourier-transform spectrometer coupled to a supersonic molecular beam leading to a rotational temperature of about 70 K. The ν6 and ν21 bands do not seem to be perturbed and the analysis of the rotational structure leads to band centers located at 933.906 6(9) and 1 103.951(1) cm−1, respectively, and to accurate rotational and centrifugal distortion constants. For the ν17 band at 2817.385(2) cm−1, only the P and R branches could be assigned. 相似文献
8.
Laser spectroscopy of the thallium atom based on transitions 6 p 1/2 → 6 D 3/2 → nF 5/2 ( n = 13–24)
The energies and quantum defects of Rydberg states nF
5/2 (n = 13–24) of the thallium atom have been studied experimentally. The Rydberg states were excited from the ground state 62
P
1/2 by the two-stage scheme through the intermediate state 62
D
3/2. By using a collimated atomic beam and monochromatic radiation of two narrow-band tunable lasers, we have succeeded in resolving
the hyperfine and isotopic structures of the ground state of the thallium atom and in determining the energy positions of
the states nF
5/2 accurate to 0.03 cm−1, which exceeds the accuracy achieved in the previous works by more than an order of magnitude. The quantum defect of nF
5/2 states is independent of n within the measurement accuracy and is equal to Δ = 1.0344 ± 0.0008. The ionization potential I
p
= 49266.55 ± 0.03 cm−1 has been found for the 205Tl isotope from the level 62
P
1/2 (F = 0). The energy of the 62
D
3/2 level measured experimentally relative to the state F = 0 of the 205 isotope amounted to 36118.56 ± 0.02 cm−1.
Original Russian Text ? P.A. Bokhan, Dm.E. Zakrevskii, V.A. Kim, N.V. Fateev, 2008, published in Optika i Spektroskopiya,
2008, Vol. 104, No. 5, pp. 771–776. 相似文献
9.
α-Y(IO3)3 and β-Y(IO3)3 are transparent until 12.8 and 13.4 μm, respectively; thus they are interesting as a potential laser matrix in the mid- and beginning of the far-infrared. So, in order to investigate the properties of lanthanides- doped anhydrous yttrium iodate, polycrystalline samples of α-Y1−xNdx(IO3)3 (0.01?x?0.05), β-Y1−xNdx(IO3)3 (0.001?x?0.1), α-Y1−xYbx(IO3)3 (0.01?x?0.33) and β-Y1−xYbx(IO3)3 (0.01?x?0.25) were synthesized. For Nd3+ ions, fluorescent emissions from the 4F3/2 multiplet were observed at 300 K under pulsed laser excitations at 750 nm and for Yb3+, fluorescent emissions from the 2F5/2 multiplet were observed at 300 K under pulsed laser excitations at 980 nm. The decays of all these emissions were measured. They are exponential and the fluorescence lifetimes are in the range 0.093-0.193 ms for Nd3+ and 0.370-0.541 ms for Yb3+, depending on the nature of the host and the concentration of doping. 相似文献
10.
Junfeng Sun Dongsheng Du Yueling Yang 《The European Physical Journal C - Particles and Fields》2009,60(1):107-117
The B
c
→J/ψ
π, η
c
π decays are studied with the perturbative QCD approach. It is found that the form factors
and
for the B
c
→J/ψ, η
c
transitions and the branching ratios are sensitive to the parameters ω, v, f
J/ψ
and
, where ω and v are the parameters of the charmonium wave functions for a Coulomb potential and the harmonic-oscillator potential, respectively,
and f
J/ψ
and
are the decay constants of the J/ψ and η
c
mesons, respectively. The large branching ratios and the clear signals of the final states make the B
c
→J/ψ
π, η
c
π decays the prospective channels for measurements at the hadron colliders. 相似文献
11.
R.Wugt LarsenF. Hegelund J. CeponkusB. Nelander 《Journal of Molecular Spectroscopy》2002,211(1):127-134
The high-resolution Fourier transform infrared spectrum of trans-glyoxal in the gas phase has been recorded in the spectral regions 700-900 cm−1, 1200-1400 cm−1, and 1600-1800 cm−1 with a resolution ranging from 0.0020 to 0.0025 cm−1. The spectrum displays extensive rotational structures which are assigned to the three fundamental bands ν6 (Au, 801.5 cm−1), ν10 (Bu, 1732.1 cm−1), and ν11 (Bu, 1312.5 cm−1). A total of ca. 5000 absorption lines have been assigned to these three bands. A simultaneous ground state combination difference analysis of all three bands yields improved ground state spectroscopic constants for trans-glyoxal. Furthermore, a number of spectroscopic constants for the ν6 and ν11 levels have been determined for the first time. 相似文献
12.
A. Chatterji 《Journal of Physics and Chemistry of Solids》2007,68(8):1603-1609
A crystal field (CF) investigation of the magnetic properties of [TbCu6(μ3-OH)3(HL)2(L)4](ClO4)2·25H2O (H2L=imino-diacetic acid) has been carried out. An enhancement of the average magnetic susceptibility (defined by =(χ||+2χ⊥)/3, where χ|| and χ⊥ are the magnetic susceptibilities parallel and perpendicular to the symmetrical axis of the cluster) with respect to the Tb3+ free ion value has been noticed and is attributed to the Tb-Cu interaction. The CF parameters obtained for the system for the first time have been exploited to find the Stark splitting of the 7F manifold of Tb3+, paramagnetic resonance g-values, and the heat capacity. Two anomalies are obtained in the heat capacity at 40 and 5 K; the peak values are 3.1 and 5.98 J mol−1 K−1, respectively. 相似文献
13.
N. Boulaftali N. Ben Sari-Zizi H. Najib G. GranerH. Bürger E.B. MkadmiP. Pracna 《Journal of Molecular Spectroscopy》2002,214(1):35-51
The ν1 (A1, 1578.31 cm−1)/ν4(E, 1615.17 cm−1) Si-D stretching dyad of D3SiF has been studied by FTIR spectroscopy with a resolution of 2.4×10−3 cm−1. Only weak interactions of Coriolis (ΔK=±1, Δ?=±1) and α resonance (ΔK=±2, Δ?=?1) type between ν1 and ν4, and of ? (2,−4) type within ν4, were revealed. However, the v1=1 and v4=1 levels were found to be severely perturbed by the v3=v5=1 (E, 1590.37 cm−1) and v2=v3=1 (A1, 1604.25 cm−1) states. These perturbations are observable only near level crossings involving strong Coriolis and α interactions. The energy structure within these perturbers is severely complicated by strong Coriolis and α resonances and by ? (2, 2), ? (2,−1), and ? (2,−4) interactions as already revealed by the ν2(A1, 710.16 cm−1) and ν5 (E, 701.72 cm−1) fundamentals. Interactions of the perturbing states with the ν1/ν4 dyad are particularly evident in local crossings. In total, 12 transitions belonging to the dark states and 68 perturbation-allowed transitions within the ν1/ν4 dyad have been detected among the more than 5000 transitions that have been assigned for the ν1/ν4 dyad, with Jmax and Kmax of 50 and 30, respectively. Altogether about 85% of the assigned transitions were fitted with a standard deviation of 0.221×10−3 cm−1, leading to 61 parameters of the interacting polyad. 相似文献
14.
O.N Ulenikov E.S Bekhtereva V.A Kozinskaia Jing-Jing ZhengSheng-Gui He Shui-Ming HuQing-Shi Zhu C LeroyL Pluchart 《Journal of Molecular Spectroscopy》2002,215(2):295-308
The high-resolution (0.005 cm−1) Fourier transform infrared spectrum of PH3 is recorded and analyzed in the region of the fundamental stretching bands, ν1 and ν3. The ν2+ν4 and 2ν4 bands are taken into account also. Experimental transitions are assigned to the ν1, ν3, ν2+ν4, and 2ν4 bands with the maximum value of quantum number J equal to 15, 15, 13, and 15, respectively. a1-a2 splittings are observed and described up to the value of quantum number K equal to 10. The analysis of a1/a2 splittings is fulfilled with a Hamiltonian model which takes into account numerous resonance interactions among all the upper vibrational states. 相似文献
15.
S. R. Palvanov Zh. Rakhmonov M. Kajumov M. I. Mamayusupova O. Zhuraev 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(2):222-225
The isomeric yield ratios of the (γ, n) and (n,2n) reactions on nuclei of 110Pd, 142Nd, and 144Sm are measured by the induced radioactivity method. The energy dependence of the isomeric yield ratios of the photonuclear
reactions 110Pd(γ, n)109m, g
Pd, and 142Nd(γ, n)141m, g
Nd, and 144Sm(γ, n)143m, g
Sm is investigated in the energy range 14–35 MeV. The results are compared to other published experimental data. 相似文献
16.
Yu-Ming Wang M. Jamil Aslam Cai-Dian Lü 《The European Physical Journal C - Particles and Fields》2009,59(4):847-860
The exclusive weak decay of Λ
b
→Λ
γ and Λ
b
→Λ
l
+
l
− are investigated in the Appelquist–Cheng–Dobrescu model, which is an extension of the standard model in the presence of universal
extra dimensions. Employing the transition form factors obtained in the light-cone sum rules, we analyze how the invariant-mass
distribution, the forward–backward asymmetry and the polarization asymmetry of the Λ baryon of these decay modes can be used to constrain the only additional free parameter with respect to the standard model,
namely, the radius, R, of the extra dimension. Our results indicate that the Kaluza–Klein modes can lead to approximately 25% suppression of the
branching ratio of Λ
b
→Λ
γ; however, their contributions can bring about 10% enhancement to the decay rate of Λ
b
→Λ
l
+
l
−. It is shown that in the present scenario the zero position of the forward–backward asymmetry of Λ
b
→Λ
μ
+
μ
− is sensitive to the compactification parameter R, while the measurement of polarizations of Λ baryon in the Λ
b
decays are not a useful tool to provide any valuable information for the universal extra-dimension model. 相似文献
17.
M. Carlotti G. di Lonardo G. Galloni A. Trombetti 《Journal of Molecular Spectroscopy》1976,62(2):192-200
The infrared absorption of HNCO has been measured in the region of the NH stretching fundamental and in that of the second overtone. The results for the excited states are (in cm?1):
Band | B | C | ||
3533.1 | 27.0 | — | — | |
10145.79 | 22.6713 | 0.368426 | 0.361722 |