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101.
[reaction: see text] A series of diimide-based macrocycles have been prepared using Mitsunobu-mediated alkylation as the macrocyclization step. These macrocycles could not be incorporated into [2]catenanes using previously established building blocks and coupling methodology. However, when one of the macrocycle syntheses was conducted in the presence of a dinaphtho crown ether, catenane formation was achieved. This result is discussed in terms of the ability of the components to establish intermolecular C-H...O hydrogen-bonding contacts. 相似文献
102.
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
103.
Ohne Zusammenfassung 相似文献
104.
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
105.
Maurice C.G. Aalders Nine v.d. Vange Fiona A. Stewart Marloes G. Klein Mark J. v.d. Vijver Henricus J.C.M. Sterenborg 《Journal of photochemistry and photobiology. B, Biology》1999,50(2-3):88-93
This study has investigated damage to the intraperitoneal organs of the rat after systemic (intraperitoneal and intravenous) administration of low doses of 5-aminolevulinic acid (ALA) and illumination with a standard white-light operating-room (o.r.) lamp. The study has been done within the framework of a larger study in which the possibility of using ALA for localization of small-volume macroscopically nonvisible peritoneal metastasis of ovarian tumors is being investigated. Fluorescence diagnostics are done in addition to the standard staging and localization procedures, either through a laparoscope or during laparotomy. In these circumstances, fluorescence diagnostics involve some risk of photosensitization of critical organs since a broad-band (o.r.) light source is used during the surgical procedures for illumination of the operating area. The drug dose and the time interval between administration of ALA and illumination are varied and normal tissues are examined both macroscopically and microscopically for damage. A relationship is demonstrated between the maximum tolerable dose (MTD) of ALA (defined as the dose that does not cause any tissue damage) and the time interval between administration and illumination. The white light that is used for illumination of the operating area is sufficient to induce damage to the peritoneal organs at relatively low ALA doses. The MDTs for 2, 6 and 16 h intervals are found to be respectively 1, 10 and 100 mg kg−1. The results are similar for both intraperitoneal and intravenous administration. 相似文献
106.
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
107.
108.
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
109.
Mathematische Zeitschrift - 相似文献
110.