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101.
The synthesis of both enantiomers of TEI-9826 has been accomplished in seven steps with an overall yield of 44% starting from diastereomeric camphor protected 3-[(dimethoxyphosphoryl)methyl]-4,5-dihydroxycyclopent-2-enones. The key steps include a fully diastereoselective hydrogenation of the endocyclic carbon–carbon double bond in the cyclopentenone ring controlled with a chiral diol moiety and the conversion of the latter into a new transposed olefinic bond. 相似文献
102.
103.
An asymptotic formula is given for the number of integers n ≤ x which do not have divisors in a fixed arithmetical progression. This extends a previous result of Banks et al. (Forum Math
20:1005–1037, 2008) who considered the case of progressions with prime difference. 相似文献
104.
105.
106.
Summary A notion of an optimal partition of a measurable space into countably many sets according to given nonatomic probability measures is defined. It is shown that the set of optimal partitions is nonempty. Bounds for the optimal value are given and the set of optimal partitions is characterized. Finally, an example related to statistical decision theory is presented. 相似文献
107.
Inventiones mathematicae - 相似文献
108.
Given a complete manifold with a particular structure at infinity, we give the dimension of the space of harmonic functions with prescribed polynomial growth. 相似文献
109.
Maciej Wawrzyniak 《Czechoslovak Journal of Physics》2006,56(1):93-98
A new method of fabricating nanowires for electric conductance quantization studies is proposed as an alternative to the method
based on converse piezoelectric effect. Commonly used for nanowire fabrication, piezoelectric actuators are expensive and
require high-level voltage control signal. The method presented in this paper is based on the use of magnetostrictive actuator.
Both the actuator structure and the method of the conversion factor measurement are discussed. The results of the tests of
the magnetostrictive actuator are also reported. The parameters of the proposed actuator are compared with those of its piezoelectric
counterpart used to date. The results of measurement confirm that the proposed actuator can be used for studying electric
conductance quantization in nanowires.
Presented at the X-th Symposium on Surface Physics, Prague, Czech Republic, July 11–15, 2005 相似文献
110.
Maciej Sewerynski 《Rendiconti del Circolo Matematico di Palermo》1991,40(3):342-346
The generalized Bell function is introduced and an ordinary differential equation which it obeys is derived. 相似文献