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81.
Local physical quantities for spin based on the relativistic quantum field theory in molecular systems
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Masahiro Fukuda Kota Soga Masato Senami Akitomo Tachibana 《International journal of quantum chemistry》2016,116(12):920-931
Local physical quantities for spin are investigated on the basis of the four‐ and two‐component relativistic quantum theory. In the quantum field theory, local physical quantities for spin such as the spin angular momentum density, spin torque density, zeta force density, and zeta potential play important roles in spin dynamics. We discuss how to calculate these local physical quantities based on the two‐component relativistic quantum theory. Some different types of relativistic numerical calculations of local physical quantities in Li atom and C6H6 are demonstrated and compared. Local physical quantities for each orbital are also discussed, and it is seen that a total local zeta potential is given as a result of some cancellation of large contributions from each orbital. © 2016 Wiley Periodicals, Inc. 相似文献
82.
Fujihara A Miyata C Maekawa A Fuke K Daigoku K Murata N Hashimoto K 《The journal of physical chemistry. A》2007,111(31):7364-7373
Photoelectron spectroscopy (PES) of Na2- (H2O)n (n < or = 6) was investigated to examine the solvation of sodium aggregates in small water clusters. The PES bands for the transitions from the anion to the neutral ground and first excited states derived from Na2 (1(1)Sigmag+) and Na2 (1(3)Sigmau+) shifted gradually to the blue, and those to the higher-excited states correlated to the 3(2)S + 3(2)P asymptote dropped down rapidly to the red and almost degenerated on the 1(3)Sigmau+-type band at n = 4. Quantum chemical calculations for n up to 3 showed that the spectra can be ascribed to structures where one of the Na atoms is selectively hydrated. From the electron distributions, it is found that the Na- -Na+(H2O)n- -type electronic state grows with increasing cluster size, which can be regarded as a sign of the solvation of Na2- with ionization of the hydrated Na. 相似文献
83.
Sumalatha Eda Baby Jyothsna Kota Prathap Kumar Thella Satyavathi Bankupalli Suresh K. Bhargava Rajarathinam Parthasarathy 《Chemical Papers》2017,71(10):1939-1951
Regeneration of carboxylic acids from the loaded-organic phase is an essential step to complete the reactive extraction process. A study on the regeneration of levulinic acid from loaded-organic phase (methyl isobutyl ketone + tri-n-octylamine + acid) was carried out using various techniques including NaOH, temperature swing, diluent swing, and tri-methylamine methods. Equilibrium data obtained show that among all the methods, the recovery of acid is the highest for the tri-methylamine method when the molar ratio of tri-methylamine to levulinic acid concentrations is greater than 1. Kinetic studies performed for the tri-methylamine method showed that there are no changes in the specific rate of extraction with changes in stirrer speed rate and phase volume ratio (V aq/V org), and the overall order of reaction is 1.5. Based on the effects of stirrer speed and phase volume ratio on the specific rate of extraction, the reaction was concluded to occur in the fast regime. Also, about 80% of acid was recovered by the evaporation of tri-methylamine phase at 104–140 °C. A detailed economic evaluation for the recovery of levulinic acid using reactive extraction for a feed rate of 2 m3 h?1 shows that the payback period for recovering capital investment is 0.49 years. 相似文献
84.
Mitsuru Kitamura Kota Otsuka Shuhei Takahashi Tatsuo Okauchi 《Tetrahedron letters》2017,58(36):3508-3511
Rh(II)-catalyzed OH insertion reaction of diazonaphthoquinones with water or alocohols proceeded to yield 1,2-naphthalenediol derivatives. 相似文献
85.
Yoshiki K. Tanaka Stefan Friedrich Hiroyuki Fujioka Hans Geissel Ryugo S. Hayano Satoru Hirenzaki Kenta Itahashi Satoshi Itoh Daisuke Jido Volker Metag Hideko Nagahiro Mariana Nanova Takahiro Nishi Kota Okochi Haruhiko Outa Ken Suzuki Takatoshi Suzuki Helmut Weick 《Few-Body Systems》2013,54(7-10):1263-1266
We are going to perform an inclusive spectroscopy experiment of η′ mesic nuclei with the 12C(p,d) reaction to study in-medium properties of the η′ meson. In nuclear medium, the η′ meson mass may be reduced due to partial restoration of chiral symmetry. In case of sufficiently large mass reduction and small absorption width of η′ at normal nuclear density, peak structures of η′ mesic states in 11C will be observed near the η′ emission threshold even in an inclusive spectrum. The experiment will be carried out at GSI with proton beam supplied by SIS using FRS as a spectrometer. The detail of the experiment is described. 相似文献
86.
Employing one- plus two-body random matrix ensembles for bosons, temperature and entropy are calculated, using different definitions, as a function of the two-body interaction strength λ for a system with 10 bosons (m=10) in five single-particle levels (N=5). It is found that in a region λ∼λt, different definitions give essentially the same values for temperature and entropy, thus defining a thermalization region. Also, (m,N) dependence of λt has been derived. It is seen that λt is much larger than the λ values where level fluctuations change from Poisson to GOE and strength functions change from Breit–Wigner to Gaussian. 相似文献
87.
Complex bands k(⊥)(E) in a semiconductor crystal, along a general direction n, can be computed by casting Schr?dinger's equation as a generalized polynomial eigenvalue problem. When working with primitive lattice vectors, the order of this eigenvalue problem can grow large for arbitrary n. It is, however, possible to always choose a set of non-primitive lattice vectors such that the eigenvalue problem is restricted to be quadratic. The complex bands so obtained need to be unfolded onto the primitive Brillouin zone. In this paper, we present a unified method to unfold real and complex bands. Our method ensures that the measure associated with the projections of the non-primary wavefunction onto all candidate primary wavefunctions is invariant with respect to the energy E. 相似文献
88.
Rathinaswamy B. Govindan Srinivas Kota Tareq Al-Shargabi Christopher B. Swisher Adre du Plessis 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(10):191
Characterization of heart rate using detrended fluctuation analysis (DFA) is impeded by respiratory oscillations. In particular, the short-term exponent measured from 15 to 30 beats is compromised in the DFA. We reconstruct respiratory signal from electrocardiograms and attenuate the respiratory oscillation in the heart rate using a frequency-dependent subtraction approach. We validate this method by applying it to an electrocardiogram signal simulated using a coupled differential equation with the respiratory oscillation modelled using a sine function. The exponent estimated using the proposed approach agreed with the exponent incorporated in the model within a narrow range. In contrast, the exponent obtained from the raw data deviated from the expected value. Furthermore, the exponents obtained for the raw heart rate are smaller than the exponents obtained for the respiration oscillation attenuated heart rate. We apply this approach to heart rate measured from 12 preterm infants that were being treated for prematurity related complications. As observed in the simulated data, we show that compared to the raw heart rate, the respiratory oscillation attenuated heart rate shows higher short-term exponent (p < 0.001). 相似文献
89.
90.
Observation of Diastereomeric Interconversions of β‐Sulfinylsubporphyrins as Evidence for Bowl Inversion
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Kota Yoshida Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11727-11734
B‐Methoxy β‐(4‐methoxyphenylsulfinyl)subporphyrin and B‐phenyl β‐(4‐methoxyphenylsulfinyl)subporphyrin were synthesized by oxidation of the corresponding β‐sulfanylsubporphyrins with m‐chloroperbenzoic acid and were separated into diastereomers, respectively. B‐Methoxy subporphyrin diastereomers were interconverted to each other in methanol or ethanol, whereas such interconversion was not observed for B‐phenyl subporphyrin diastereomers even at high temperature. Diastereomeric interconversions of B‐methoxy subporphyrins were dramatically accelerated by addition of trifluoroacetic acid. These results suggest that the diastereomeric interconversions of B‐methoxy subporphyrins, namely, their bowl inversions, proceed via a mechanism involving protonation‐induced generation of subporphyrin borenium cations followed by nucleophilic attacks by alcohols. 相似文献