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41.
We examine the role of the non-locality of the potential in the two-body scattering by taking the nucleon-Σ system as an example. We employ a non-local potential for the nucleon-Σ channel which has the characteristic features of the quark model and reproduces the phase shifts of widely used local potentials. We use inverse scattering methods to obtain the equivalent local potential from the non-local potential, and show that the obtained local potential has a strong short range repulsion.  相似文献   
42.
Nanoparticles in Emissions and Atmospheric Environment: Now and Future   总被引:5,自引:0,他引:5  
Journal of Nanoparticle Research -  相似文献   
43.
44.
We consider a hyperbolic–parabolic singular perturbation problem for a quasilinear hyperbolic equation of Kirchhoff type with dissipation weak in time. The purpose of this paper is to give time‐decay convergence estimates of the difference between the solutions of the hyperbolic equation above and those of the corresponding parabolic equation, together with the unique existence of the global solutions of the hyperbolic equation above. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
45.
Bremsstrahlung photons associated with the α-decay of210Po were measured in α-γ coincidence measurements with Si and Ge detectors. Emission probabilities of the bremsstrahlung deduced for210Po were 10−11∼10−12/keV/sr/decay for 100≤E γ≤600 keV. It was found that the bremsstrahlung yields are much smaller than those predicted by a Coulomb acceleration model. This suggests that α-particles also emit photons inside the barrier. The bremsstrahlung spectrum was compared with a quasi-classical calculation in which the bremsstrahlung emission in tunneling motion of α-particles is taken into account. It is shown that the data can be interpreted as a consequence of destructive interference of radiative amplitudes outside the Coulomb barrier with those in tunneling.  相似文献   
46.
Many reports on the mass spectra of organotransition-metal complexes have appeared in recent years,1 whilst there have only been a few reports on the mass spectra of transition metal olefin complexes, some metal carbonyl olefin complexes234 and π-cyclooctenyl-π-cyclooctadienyl cobalt.5 Recently fragmentation paths of π-cyclopentadienyl-cyclooctadiene rhodium were elucidated by King.6 The present authors found metastable ions in the mass spectra of π-cyclopentadienyl-diene cobalt complexes as well as in the mass spectra of π-cyclopentadienyl-diene rhodium complexes.7. In the present paper the authors wish to report the mass spectra of several π-cyclopentadienyl diene cobalt complexes.  相似文献   
47.
In order to know the distribution of plutonium derived from the Nagasaki atomic bomb, soil samples were measured to determine the 240Pu/239Pu isotope ratio of and concentrations of 239+240Pu and 137Cs. The 239+240Pu concentrations in soils, except for Nishiyama area, were close to the average concentration of soil collected in Japan. In soils collected at the Nishiyama area and at the eastern area of Nagasaki Prefecture and at part of northern area in Kumamoto Prefecture, the 240Pu/239Pu ratios were lower than the global fallout values. This suggests that plutonium from the atomic bomb was deposited in the eastern area from the hypocenter reaching up to 100 km eastwards.  相似文献   
48.
49.

Circularly polarized luminescence (CPL) organic dyes are currently receiving a great interest, but there are still not many reported observations of CPL spectra of hydrophobic dyes from aqueous solution. We have prepared hydrophobic pyrene derivatives and dissolved them into aqueous solutions with γ-cyclodextrin (γ-CD) by using grinding technique. Among these derivatives, (pyrene-1-carbonyl)serine (PySer) forms a spatially restricted dimer in the hydrophobic chiral cavity of γ-CD and exhibits excimer emission with a high quantum yield of Φf?=?0.68. In addition, circular dichroism and CPL signals were induced for the complex. The strong gCPL value of gCPL?=?+?2.2?×?10?3 was obtained, which may be attributed to the interaction between the hydroxyl groups in the side chain of PySer with those of γ-CD and it strengthens the chiral dimeric structure.

Graphic abstract
  相似文献   
50.
Anemia is a major complication of chronic renal failure. To treat this anemia, prolylhydroxylase domain enzyme (PHD) inhibitors as well as erythropoiesis-stimulating agents (ESAs) have been used. Although PHD inhibitors rapidly stimulate erythropoietin (Epo) production, the precise sites of Epo production following the administration of these drugs have not been identified. We developed a novel method for the detection of the Epo protein that employs deglycosylation-coupled Western blotting. With protein deglycosylation, tissue Epo contents can be quantified over an extremely wide range. Using this method, we examined the effects of the PHD inhibitor, Roxadustat (ROX), and severe hypoxia on Epo production in various tissues in rats. We observed that ROX increased Epo mRNA expression in both the kidneys and liver. However, Epo protein was detected in the kidneys but not in the liver. Epo protein was also detected in the salivary glands, spleen, epididymis and ovaries. However, both PHD inhibitors (ROX) and severe hypoxia increased the Epo protein abundance only in the kidneys. These data show that, while Epo is produced in many tissues, PHD inhibitors as well as severe hypoxia regulate Epo production only in the kidneys.  相似文献   
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