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71.
Astakhov GV Dzhioev RI Kavokin KV Korenev VL Lazarev MV Tkachuk MN Kusrayev YG Kiessling T Ossau W Molenkamp LW 《Physical review letters》2008,101(7):076602
We report a surprisingly long spin relaxation time of electrons in Mn-doped p-GaAs. The spin relaxation time scales with the optical pumping and increases from 12 ns in the dark to 160 ns upon saturation. This behavior is associated with the difference in spin relaxation rates of electrons precessing in the fluctuating fields of ionized or neutral Mn acceptors, respectively. For the latter, the antiferromagnetic exchange interaction between a Mn ion and a bound hole results in a partial compensation of these fluctuating fields, leading to the enhanced spin memory. 相似文献
72.
G. P. Mikhailov V. V. Lazarev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(7):1367-1373
The effect the number of chitosan monomer units CTSn (n = 1–5), the protonation of chitosan dimers, and the interaction between CTSn (n = 1–3) and acetate ions have on the energy of intramolecular hydrogen bonds is investigated by means of QTAIM analysis and solving the vibrational problem within the cluster-continuum model. It is established that the number of H-bonds in CTSn is 2n ? 1 and the total energy of H-bonds grows by ~20 kJ/mol. It is concluded that the hydrogen bonds between CTS and acetate ions play a major role in the stabilization of polyelectrolyte complexes in dilute acetic acid solutions of CTS. 相似文献
73.
74.
Evgeny R. Gafarov Alexander A. Lazarev Frank Werner 《Annals of Operations Research》2012,196(1):247-261
We consider the problem of maximizing total tardiness on a single machine, where the first job starts at time zero and idle times between the processing of jobs are not allowed. We present a modification of an exact pseudo-polynomial algorithm based on a graphical approach, which has a polynomial running time. This result settles the complexity status of the problem under consideration which was open. 相似文献
75.
Yu. A. Draginda S. G. Yudin V. V. Lazarev S. V. Yablonskii S. P. Palto 《Crystallography Reports》2012,57(3):421-425
The potential of the vacuum method for preparing ferroelectric films and photonic heterostructures from organic materials is studied. Vacuum-evaporated films of fluoropolymers and heterostructures on their basis are obtained and their ferroelectric and spectral properties are studied. In particular, homogeneous films of the well-known piezoelectric polymer polyvinylidene fluoride and ferroelectric material vinylidene fluoride/trifluoroethylene copolymer (P(VDF/TFE)) are produced. Experimental studies of vacuum-evaporated P(VDF/TFE) films confirmed their ferroelectric properties. The heterostructures composed of alternating layers of P(VDF/TFE) copolymer molecules and azodye molecules are fabricated by vacuum evaporation. Owing to the controlled layer thickness and a significant difference in the refractive indices of the P(VDF/TFE) copolymer and azodyes, these heterostructures exhibit properties of photonic crystals. This finding is confirmed by the occurrence of a photonic band in the absorption spectra of the heterostructures. 相似文献
76.
V. V. Lazarev M. T. Khatmullina L. V. Rabchuk A. S. Krauze 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(1):63-68
The results from investigating interactions between tetramethylurea (TMU) and water molecules by means of Raman light scattering
spectroscopy (RS) are presented. It is established that spectroscopic manifestations of association of TMU and H2O molecules are observed for the TMU molecule valence vibration band ν(CO) 1638 cm−1. By means of quantum-chemical calculations, it is shown that the band sensitivity to molecular environment is defined by
the number of 5–6 H2O molecules. It is found that in a pure TMU medium, chain dimers are formed due to the interactions of molecular dipoles arranged
in parallel and hydrogen bonds of the C-H…O type. Ground state geometries of TMU, TMU-TMU, H2O molecules and TMU · (H2O)
n
complexes (n = 1−14) are optimized by the density functional B3LYP procedure, using the 6–31++G(d, p) basis set. The main vibration frequencies are calculated in the harmonic approximation. Associate formation energies are
calculated with allowance for the basis set superposition error (BSSE). 相似文献
77.
Various types of resonant elements that can be used for increasing the transmission loss of panels in narrow frequency bands are analyzed. The main physical phenomena determining the transmission loss of sound waves in panels with resonant elements are studied. Three main principles of increasing the transmission loss realized in panels with resonant elements are described: the principle of soft reflection, the principle of hard reflection, and the principle of compensation. The relations for estimating the transmission loss of panels with resonant elements, which model the main physical phenomena governing the propagation of sound waves, are presented. 相似文献
78.
Rumyantcev R. V. Zolotareva N. V. Novikova O. V. Petrov B. I. Lazarev N. M. Semenov V. V. 《Crystallography Reports》2021,66(3):441-447
Crystallography Reports - Reactions of nitrilotriacetic acid with 2-aminoethanol, 2-amino-2-(hydroxymethyl)propane-1,3-diol, and 2,2'-(ethylenedioxy)bis(ethylamine) afford the following salts... 相似文献
79.
V. G. Grebinnik V. N. Duginov V. A. Zhukov S. Kapusta A. B. Lazarev V. G. Olshevsky V. Yu. Pomjakushin S. N. Shilov I. I. Gurevich B. F. Kirillov E. P. Krasnoperov B. A. Nikolsky A. V. Pirogov A. N. Ponomarev V. A. Suetin A. I. Morozov 《Hyperfine Interactions》1991,63(1-4):241-247
High temperature superconductors HoBa2Cu3O7−δ (T
c
≅93 K), Ho0.5Y0.5Ba2Cu3O7−δ (T
c
≅93 K) and ErBa2Cu3O7−δ (T
c
≅95 K) were investigated by the zero-field μSR-technique. The muon spin depolarisation rate connected with the fluctuation
frequency of rare-earth ion magnetic moments was measured. It was found that the samples with holmium show a fast increase
of the muon spin depolarisation rate at temperatures below 20 K, while in ErBa2Cu3O7−δ the depolarisation rate remains low in the whole temperature region studied (4.2 K-270 K). The sharp difference between the
behaviours of the muon spin depolarisation rate may be explained by the difference between the ground state of Ho3+ and Er3+ ions in the crystalline field of the lattice. 相似文献
80.
S. G. Barsov A. L. Getalov G. Grebinnik I. I. Gurevich B. F. Kirillov A. I. Klimov S. P. Kruglov L. A. Kuzmin A. B. Lazarev S. M. Mikirtychyants N. I. Moreva B. A. Nikolsky A. V. Pirogov A. N. Ponomarev V. I. Selivanov G. V. Shcherbakov S. N. Shilov V. A. Suetin V. A. Zhukov 《Hyperfine Interactions》1986,31(1-4):339-343
It is shown that the temperature dependence Λ (T) of the muon spin relaxation rate in the paramagnetic state of dysprosium
and holmium does not reveal any singularity at T−>TN′ where TN is the Neel temperature. This result contradicts the assumption of the second-order antiferromagnetic phase-transition in
these metals and is in good agreement with computations within the renormalization group method. 相似文献