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61.
Delayed γ-ray spectra as well as time distributions have been measured applying the r.f.-γ method and the method of delayed γ-γ coincidences. Using the reaction 175Lu(α, 2n)177Ta, the half-lives of the levels at 70.6 and 73.6 keV in 177Ta have been determined as and , respectively. In further experiments, upper limits for the lifetimes of the and states in 171Lu and 173Lu were estimated. Comparisons of the experimental half-lives to Weisskopf and Nilsson model predictions are performed taking into account pairing correlations. For the calculations, a modified Nilsson Hamiltonian has been used. The hindrance factors obtained are summarized together with those deduced for corresponding transitions in neighbouring odd-proton nuclei. From the experimental results in 177Ta, conclusions have been drawn on the possible value of the constant k2 occurring in the magnetic dipole operator. 相似文献
62.
The NOE enhancement factor in 1H NMR spectroscopy is shown to be a function of dipole-dipole interaction of the solute. The NOE increases with increasing concentration if a monomer-dimer equilibrium exists in solution. 相似文献
63.
64.
The Kirillov–Reshetikhin modules Wr,s are finite-dimensional representations of quantum affine algebras U’q labeled by a Dynkin node r of the affine Kac–Moody algebra
and a positive integer s. In this paper we study the combinatorial structure of the crystal basis B2,s corresponding to W2,s for the algebra of type D(1)n.
2000 Mathematics Subject Classification Primary—17B37; Secondary—81R10
Supported in part by the NSF grants DMS-0135345 and DMS-0200774. 相似文献
65.
Hardy F Hillier NJ Meingast C Colson D Li Y Barišić N Yu G Zhao X Greven M Schilling JS 《Physical review letters》2010,105(16):167002
It is well known that the superconducting transition temperature (T(c)) of cuprate superconductors can be enhanced by varying certain structural and electronic parameters, such as the flatness of the CuO? planes or their doping level. We determine the uniaxial and hydrostatic pressure derivatives of T(c) in the structurally simple tetragonal compound HgBa?CuO(4+δ) near optimal doping. Our results provide experimental evidence for two further methods to enhance T(c): (i) reducing the area of the CuO? planes, and (ii) increasing the separation of the CuO? planar groups. T(c) is found to couple much more strongly to the ratio c/a of the lattice constants than to the unit cell volume. A comparison with prior results for structurally more complicated cuprates reveals a general trend of uniaxial pressure derivatives with T(c). 相似文献
66.
67.
James S. Schilling 《物理学进展》2013,62(5):657-715
A large body of data is reviewed, which illustrates how the high pressure technique can be used to gain information about the magnetic and electronic state of dilute magnetic alloys. Values for the pressure dependence of the elementary effective exchange interaction between a magnetic impurity spin and the conduction electron sea are extracted from the data and tabulated for a number of extremely dilute alloys containing both transition metal and rare earth impurities. Results of experiments on host alloy series employing ‘lattice pressure’ are compared to the present ‘external pressure’ results and critically analysed; it is shown how such a comparison can be used to give information about the extent of the electronic screening around an impurity potential. The effect of pressure on impurity-impurity interactions in spin glasses is also examined; a comparison of the pressure studies on extremely dilute alloys to those on spin glasses allows an estimate of the nature of the interaction mechanisms important in the latter case. Evidence for a pressure-induced spin glass to Kondo transition in LaCe is also presented. It is suggested that the present results fit into a larger picture that magnetism, when present, tends to be weakened when high pressure is applied. 相似文献
68.
Jongseo Park Michael R. Schilling Herant Khanjian Jiyoung Lee 《Chromatographia》2018,81(12):1685-1694
A lacquered wooden coffin decorated with gilded Sanskrit letters excavated in the Nongso ancient tomb site was constructed around the fourteenth century in Korea. Pyrolysis/gas chromatography/mass spectrometry was employed to identify the materials of the lacquered surface by analyzing the individual layers. The components of lacquer were detected in all four layers of wood substrate, black, brown, and gilded layers, indicating the coating material was Asian lacquer. The wood seems to be a kind of pine tree from the observation that pine resin-related components were detected in much of the wood substrate and decreasing in the upward direction. Markers of drying oil like azelaic acid and palmitic acid existed in large quantities in the black, brown, and gilded layers, indicating that drying oil was intentionally added to give a luster. In addition, compared with dried Asian lacquer from Korea, the lacquer used in the coffin was determined to be of the same type. 相似文献
69.
Wilson William L. Curtis K. Tackitt M. Hill A. Hale A. Schilling M. Boyd C. Campbell S. Dhar L. Harris A. 《Optical and Quantum Electronics》2000,32(3):393-404
The long held promise of using volume holography to deliver high performance optical storage is reviewed. The problems, which limited the development for many years, are accessed. Finally, we describe a series of innovations, which may make the technology viable at last. 相似文献
70.
Schilling Carolin Zähres Manfred Mayer Christian Winterer Markus 《Journal of nanoparticle research》2014,16(7):1-15
Printed electronics, as an extension to conventional electronics, has grown considerably for decades. At this moment, therefore, tracing the development of this technology up to the present will provide researchers and R&D planners with better understanding of the technology’s evolving characteristics and insights for further R&D directions. This paper carries out two bibliographic analyses to study the technology development life cycle and the technological knowledge within the area of printed electronics. First, we fit a growth curve to yearly patent registration data, thereby calculating several indicators, including the current technological maturity ratio, the number of potential future patents and the expected remaining life. Second, we identify the core and brokering technology classes within the overall technology network of printed electronics by combining patent co-classification analysis and social network analysis. As a result, we could obtain some findings from the inventional point of view; the technological development of printed electronics has entered the maturity stage, and the expected remaining life was 8.5 years as of the beginning of 2013. In addition, we identified several technology areas that have the high importance to act as both core and brokering technologies, apparatus for metal working, anti-inductive structures, and electronic circuit control systems. 相似文献