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51.
A photo-induced radical pair of FADH· and Y8· and in BLUF protein SyPixD was studied by pulsed electron paramagnetic resonance (EPR) spectroscopy. Blue light illumination at 150 K for 30 min followed by cooling to 50 K during illumination induced the stable radical pair. The EPR signal has been characterized by a Pake doublet signal with complete S = 1 spin state. The radical pair was utilized as a probe to analyze the oligomer of SyPixD. The relative arrangement of PixD proteins in the complex was investigated by pulsed electron–electron double resonance (PELDOR) with the orientation selection. Based on the decameric structure in the crystal, the possible structure for the PELDOR results was discussed.  相似文献   
52.
We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2=0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51+/-0.57 (stat)+/-0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions.  相似文献   
53.
We have investigated the nucleation and evolution of germanium (Ge) nanodot (ND)s taking place while depositing Ge onto the silicon (Si) (1 1 1) surfaces with ultra-thin Si oxide films by using ultra-high vacuum in situ high-resolution transmission electron microscopy in the profile-imaging geometry. Various types of growth phenomena such as nucleation, growth and coalescence of Ge NDs have successfully been observed. The results show that the growth phenomena of the Ge NDs are dramatically rapid after their size reaches the size of the critical nucleus. The critical nucleus size estimated from a model using the cohesive energy of the Ge NDs has been consistent with observed one.  相似文献   
54.
We have performed zero-field muon-spin-relaxation measurements on single crystals of La(2-x)SrxCuO4 to search for spontaneous currents in the pseudogap state. By comparing measurements on materials across the phase diagram, we put strict upper limits on any possible time-reversal symmetry breaking fields that could be associated with the pseudogap. Comparison between experimental limits and the proposed circulating current states effectively eliminates the possibility that such states exist in this family of materials.  相似文献   
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T. Ito  W.M. Gibson 《Surface science》1985,161(1):115-128
Monte Carlo calculations have been performed to evaluate the surface peak from 1 MeV He ions incident on Si(001) and Si(111) crystal surfaces. Detailed angular dependences of the surface peaks were obtained for tilt angles of ?2° and azimuthal angles of ?45° in the vicinity of axial channeling directions. The validity of the triangular background subtraction is discussed for cases of tilted incidence from axial channeling directions. The multiple scattering effect in thin adlayers on the crystal, which is important in application of MeV ion scattering to interfaces studies, is simulated and correlated with evaluation of the interface peak value of the substrate atoms.  相似文献   
58.
An average energy of a high temperature part of ions in turbulently heated plasmas was measured by use of a secondary emission detector, and availability of this simple method for a determination of an average ion energy was discussed.  相似文献   
59.
We investigate the relation between the Lee-Yang circle theorem and the correlation inequalities. These results are general and independent of models. General properties of the partition functions which belong to the Lee-Yang class are given.  相似文献   
60.
We first construct a Fock space with an indefinite metric ,=( , ), where is a unitary and Hermitian operator. We define a -selfadjoint (Segal's) field (f) which obeys the canonical commutation relations (CCR) with an indefinite metric. We consider a transformation 349-2 (T = real linear) which leaves the CCR invariant. We investigate the implementability of T by an operator on the Fock space.  相似文献   
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