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81.
A. Michalowicz R. Clement 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(3):265-271
Intercalation of various cations into layered MnPS3 induces some disorder in the local structure of Mn(II) cations, observable by EXAFS at the manganese K edge. The amplitude of this disorder effect is correlated with the amplitude of the weak ferromagnetism also observed at low temperature in the intercalates. 相似文献
82.
One‐Step Synthetic Access to Isosteric and Potent Anticancer Nitrogen Heterocycles with the Benzo[c]phenanthridine Scaffold 下载免费PDF全文
Tamara N. Steinhauer Dr. Ulrich Girreser Dr. Christopher Meier Prof. Dr. Mark Cushman Prof. Dr. Bernd Clement 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8301-8308
A versatile one‐step two‐component cyclization to build new tetracyclic nitrogen heterocycles is described. Ortho‐methylhetarenecarbonitrile components were condensed with aldehydes to access a large library of differently substituted ring systems. The heterocyclic core can be easily modified by variation of the position of the endocyclic nitrogen atom in the o‐methylhetarenecarbonitrile substrate. The manner of the nucleophilic attack that leads to the condensation can be triggered by different electron‐density distribution in the molecule induced by the position of the nitrogen atom. Taking this into account, there is an electronic preference that leads to either pyridophenanthrolines or the corresponding pyridoazacarbazoles as the main products. We demonstrate the high antitumor potential of some of our synthesized heterocycles, which is strongly dependent on the substitution pattern introduced through the aldehyde component. The position and number of endocyclic nitrogen atoms play an important role regarding cytotoxicity of the studied compounds. 相似文献
83.
Noah Kyame Asare-Donkor Patrick Adu Poku Eric Clement Desmond Kotei Addison David Dotse Wemengah Anthony Apeke Adimado 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):675-683
Radon in groundwater and their annual effective dose in the Ashanti region of Ghana have been determined using the continuous grab sampling technique and an AB-5 detector. Mean levels of radon were in the range of 0.51–46.16 Bq L?1. Effective annual doses ranged from 0.18–16.16, 0.13–12.08 and 0.09–8.31 μSv y?1 for infants, children and adults, respectively. These values are significantly lower than the reference level of 0.1 mSv y?1 recommended by the WHO and United Nations Scientific Committee on the Effects of Atomic Radiation for members of the public. 相似文献
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Emmanuelle Clement 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(1-2):109-127
We consider the problem of the non-sequential detection of a change in the drift coefficient of a stochastic differential equation, when a misspecified model is used. We formulate the generalized likelihood ratio (GLR) test for this problem, and we study the behaviour of the associated error probabilities (false alarm and nodetection) in the small noise asymptotics. We obtain the following robustness result: even though a wrong model is used, the error probabilities go to zero with exponential rate, and the maximum likelihood estimator (MLE) of the change time is consistent, provided the change to be detected is larger (in some sense) than the misspecification error. We give also computable bounds for selecting the threshold of the test so as to achieve these exponential rates. 相似文献
86.
The strong Chebyshev distribution and the Chebyshev orthogonal Laurent polynomials are examined in detail. Explicit formulas are derived for the orthogonal Laurent polynomials, uniform convergence of the associated continued fraction is established, and the zeros of the Chebyshev L-polynomials are given. This provides another well-developed example of a sequence of orthogonal L-polynomials 相似文献
87.
Frequency-resolved optical gating is used to characterize the propagation of intense femtosecond pulses in a nonlinear, dispersive medium. The combined effects of diffraction, normal dispersion, and cubic nonlinearity lead to pulse splitting. The role of the phase of the input pulse is studied. The results are compared with the predictions of a three-dimensional nonlinear Schr?dinger equation. 相似文献
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