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81.
A mild and high-yielding cyanating reaction of amine, sulfur, and carbanion nucleophiles is reported here using 1-cyanoimidazole as an electrophilic cyanating agent. 相似文献
82.
Ohne Zusammenfassung 相似文献
83.
Trembling-hand arguments, introduced by Selten, where players make errors in implementing a strategy, are a successful and
intuitively plausible approach to eliminating some equilibria. Typically, these errors are independent of the strategy the
player aims to implement. In many contexts, however, when a player aims at one strategy, some errors are more likely than
if a different strategy is the target. We introduce the notion of strategy-dependent trembles where each strategy intended by a player implies a different probability vector of errors over other strategies.
This seemingly minor but plausible change makes a major difference. The focus becomes a player's own errors rather than the
errors of others. A weakly dominated strategy is not necessarily eliminated if less costly errors arise when aiming at it
than at the dominating strategy. Almost every Nash equilibrium in pure strategies is a strategy-dependent trembling-hand perfect
equilibrium.
We thank the associate editor, two referees, James Friedman, and audiences at the Public Choice Society Meetings and Southeastern
Economic Theory Meetings for comments and the Public Utility Research Center and the College of Business Administration at
the University of Florida for financial support. 相似文献
84.
T. F. Hamilton W. L. Robison S. Kehl A. C. Stoker C. L. Conrado 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(2):415-422
The Lawrence Livermore National Laboratory has developed an extensive quality assurance program to provide high quality data and assessments in support of the Marshall Islands Dose Assessment and Radioecology Program. Our quality assurance objectives begin with the premise of providing integrated and cost-effective program support (to meet wide-ranging programmatic needs, scientific peer review, and build public confidence) and continue through from design and implementation of large-scale field programs, sampling and sample preparation, radiometric and chemical analyses, documentation of quality assurance/quality control practices, exposure assessments, and dose/risk assessments until publication. The basic structure of our radioassay quality assurance/quality control program can be divided into four essential elements: (1) sample and data integrity control, (2) instrument validation and calibration, (3) method performance testing, validation, development and documentation, and (4) periodic peer review and on-site assessments. While our quality assurance objectives are tailored towards a single research program and the evaluation of major exposure pathways/critical radionuclides pertinent to the Marshall Islands, we have attempted to develop quality assurance practices that are consistent with proposed criteria designed for laboratory accreditation. 相似文献
85.
86.
D. N. Poenaru W. Greiner J. H. Hamilton A. V. Ramayya 《Acta Physica Hungarica A》2001,14(1-4):285-295
Experimental results on particle accompanied cold fission of 252Cf suggest the existence of a short-lived quasi-molecular state. Within our three-center phenomenological model, described in this paper, we found a possible explanation based on a new minimum in the deformation energy at a separation distance very close to the touching point. Half-lives of some quasimolecular states which could be formed in 10Be accompanied fission of 236U, 236Pu, 246Cm, 252Cf, 252,256Fm, 256,260No, and 262Rf are roughly estimated. 相似文献
87.
Mathematische Zeitschrift - 相似文献
88.
89.
Nathan Ravi Arpita Mitra Paul Hamilton Ferenc Horkay 《Journal of Polymer Science.Polymer Physics》2002,40(23):2677-2684
The characteristics of poly(ethylene glycol) (PEG)–acrylate hydrogel networks were investigated as a function of the ethanol–water solvent composition during free‐radical crosslinking copolymerization. Macromonomer (88% ω‐methoxy‐PEG–acrylate and 10% ω‐phenoxy‐PEG–acrylate) and crosslinker (2% PEG–diacrylate) concentrations were kept constant. As the copolymerization progressed, the polymer solution in 100% ethanol became increasingly turbid, indicating the development of a heterogeneous network structure. In 100% water, however, the initially turbid polymer solution became increasingly transparent as the crosslinking copolymerization progressed. All the gels were optically clear upon equilibration in water. Kinetic studies, with attenuated total reflectance‐infrared, showed a long induction period, along with a lowered reaction rate, in 100% ethanol, and a decrease in conversion with an increase in ethanol content. These results agree with the UV analysis of the sol fractions, which indicated an increase in the amounts of unreacted PEG–acrylates with an increase in the ethanol content. The gels which were formed with a high ethanol concentration exhibited lower Young's modulus and higher swelling ability, suggesting that the network structure was significantly affected by the solvent composition during free‐radical crosslinking copolymerization. From the stress–strain and swelling experiments, the Flory–Huggins interaction parameter was evaluated. The creep characteristics of the hydrogels were modeled with two Kelvin elements. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2677–2684, 2002 相似文献
90.