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111.
The following estimate of the pth derivative of a probability density function is examined: , where hk is the kth Hermite function and Σi = 1nhk(p)(Xi) is calculated from a sequence X1,…, Xn of independent random variables having the common unknown density. If the density has r derivatives the integrated square error converges to zero in the mean and almost completely as rapidly as O(n?α) and O(n?α log n), respectively, where . Rates for the uniform convergence both in the mean square and almost complete are also given. For any finite interval they are O(n?β) and , respectively, where . 相似文献
112.
Andrzej Maślankiewicz Mirosław Wyszomirski Tadeusz Głowiak Adolf Gogoll 《Journal of chemical crystallography》1991,21(5):559-565
The title compound (C11H11NS2) is monoclinic:P21/c,a=15.200(4),b=14.644(4),c=10.098(3),Z=8. The structure was solved by direct methods, and refined to anR value of 0.047 with 2886 independent reflections. There are two nonequivalent molecules in the unit cell. BothS-methyl groups have different spatial orientation: the-methyl group side-chain is approximately coplanar with the pyridine ring and turned to the ortho-position, but -methyl group side-chain is turned over this ring. Both1H and13C NMR spectra were assigned using 1D and 2D experiments. The NOE measurements are consistent with inter-proton distances from X-ray data.Part XV in the series of Azinyl sulfides. 相似文献
113.
Andrzej Maślankiewicz Tadeusz Głowiak Stanisław Boryczka Mirosław Wyszomirski 《Journal of chemical crystallography》1996,26(11):763-767
The title compound crystallizes in a monoclinic space groupP21/n witha=9.524(3),b=6.782(2),c=26.217(6) Å, =92.52(4)°. The values of the Cl...S and S...S distances are well below the sum of the van der Waals radii of the heteroatoms. Also, the Cl–C–C(S) and (Cl)C–C–S bond angles are below the standard 120°. This indicates a attractive interaction between both pairs ofortho-situated heteroatoms.Part XXXVIII in the Series of Azinyl Sulfides. 相似文献
114.
Dr. Mirosław Salamończyk Dr. Damian Pociecha Dr. Agnieszka Nowak‐Król Dr. Dominik Koszelewski Prof. Daniel T. Gryko Prof. Ewa Górecka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(20):7384-7388
Incorporation of four trialkoxyphenyl substituents combined with extending the π‐conjugated system has allowed porphyrins to display liquid‐crystalline columnar phases at room temperature. 2D and 3D columnar structures were observed as well as a biaxial smectic phase. 相似文献
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Roszak Kinga Katrusiak Andrzej Dega-Szafran Zofia Komasa Anna Kowalczyk Iwona Szafran Mirosław 《Structural chemistry》2017,28(3):859-865
Structural Chemistry - The cation of 3-(trimethylammonium)-benzoic acid exhibits a considerable conformational flexibility connected to the orientation of carboxyl group, coupled to the proton... 相似文献
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Jan Zawadiak Mirosław Danch Mariola Pigulla 《Monatshefte für Chemie / Chemical Monthly》2001,132(7):821-824
Summary. Syntheses of novel primary-tertiary bisperoxides were carried out under phase transfer catalysis conditions. The bisperoxides
were obtained in good yields, the reaction times not exceeding four hours.
Received January 15, 2001. Accepted (revised) February 9, 2001 相似文献
120.