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111.
112.
Nils Dalarsson 《International Journal of Theoretical Physics》1996,35(4):783-805
Pion-nucleon scattering amplitudes as well as Born amplitudes are calculated in a constant-cutoff approach to the canonical
quantization of skyrmions, with the subsidiary conditions imposed on the quantum fields and their conjugate momenta such that
all infrared singularities from the zero-frequency modes are eliminated. It is shown that the Born terms with recoil corrections
are reproduced by the pion-nucleon linear and quadratic interactions. 相似文献
113.
The unsymmetrical N,N,N-trimethyl tris-indolobenzene 3 has been synthesized by several routes, including cyclotrimerization of the O-acetate of indoxyl. This condensation involves a 3→2 rearrangement of the precursor formed in situ. Similar Wagner-Meerwein rearrangements were also prevalent in LAH reductions of some 3,3-diindolyl oxindoles.Treatment of the 3,3-diindolyl indolines with strong acid resulted in a cleavage yielding 3,3'-biindolyls. 相似文献
114.
X-ray photoelectron spectroscopy (ESCA) has been used in a study of CO and O2 chemisorbed on a polycrystalline tungsten sample. Working under ultra-high vacuum conditions, the surface was cleaned and then covered with known monolayer and fractional monolayer quantities of adsorbed CO and O2. The O(ls) and C(ls) spectral features were detected, and the influence of an adsorbed layer on the tungsten spectral features was determined. A chemical shift of 3.4 eV in the O(ls) line from chemisorbed CO is related to the different modes of bonding of CO to tungsten. A model calculation of the photoelectron yields expected from an adsorbed monolayer is in good agreement with the experimental results. 相似文献
115.
The substitution pattern of the two major petroporphyrins of Marl Slate, the ETIO III and the C32 DPEP, is determined by NMR spectroscopy alone, using self-aggregation effects, nuclear Overhauser enhancements and spin-lattice relaxation times. Protoporphyrin IX dimethyl ester was used as a model compound. 相似文献
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Nils?Lid?Hjort Andrea?OngaroEmail author 《Statistical Inference for Stochastic Processes》2005,8(3):227-254
Two characterisations of a random mean from a Dirichlet process, as a limit of finite sums of a simple symmetric form and
as a solution of a certain stochastic equation, are developed and investigated. These are used to reach results on and new
insights into the distributions of such random means. In particular, identities involving functional transforms and recursive
moment formulae are established. Furthermore, characterisations for several choices of the Dirichlet process parameter (leading
to symmetric, unimodal, stable, and finite mixture distributions) are provided. Our methods lead to exact simulation recipes
for prior and posterior random means, an approximation algorithm for the exact densities of these means, and limiting normality
theorems for posterior distributions. The theory also extends to mixtures of Dirichlet processes and to the case of several
random means simultaneously. 相似文献
120.