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101.
Two novel polymerizable dyes with anthraquinone residue have been prepared, and their structures were characterized by FTIR, ^1HNMR and EA.  相似文献   
102.
103.
The exponential functional of simple, symmetric random walks with negative drift is an infinite polynomial Y = 1 + ξ1 + ξ1ξ2 + ξ1ξ2ξ3 + ⋯ of independent and identically distributed non-negative random variables. It has moments that are rational functions of the variables μ k = E k ) < 1 with universal coefficients. It turns out that such a coefficient is equal to the number of permutations with descent set defined by the multiindex of the coefficient. A recursion enumerates all numbers of permutations with given descent sets in the form of a Pascal-type triangle. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
104.
Periodica Mathematica Hungarica - In our paper we study the usage of partially defined Boolean functions (PDBFs) for generating cryptographically strong Boolean functions. A PDBF can be considered...  相似文献   
105.
A note on a generalized Douglas space   总被引:1,自引:0,他引:1  
Periodica Mathematica Hungarica -  相似文献   
106.
Paramagnetic pyrroline and 1,2,3,6-tetrahydropyridine derivatives of BODIPY and their diamagnetic analogs have been synthesized and characterized as novel redox double sensor and cation sensitive reagents.  相似文献   
107.
Bed&#x  ich Ko&#x  ata  V  clav Kozmik  Ji&#x  í  Svoboda  Vladimí  ra Novotn    P&#x  emysl Van   k  Milada Glogarov 《Liquid crystals》2003,30(5):603-610
Four series of new [1]benzothieno[3,2- b ][1]benzothiophene derivatives have been synthesized. In the non-chiral series a SmA phase occurs, while the chiral series exhibits a rather wide antiferroelectric SmC * A phase just below the SmA phase. The SmA-SmC * A phase transition has been studied using DSC and dielectric spectroscopy. In the SmC * A phase the spontaneous quantities have been measured. The tilt angle shows a typical temperature dependence and the values of spontaneous polarization are rather moderate. The length of the helical pitch increases on increasing the length of the non-chiral alkyl chain.  相似文献   
108.
The influence of the sample orientation on the effective value of the hydrostatic piezoelectric coefficients d h (i) of Sn2P2S6 crystals has been studied. The hydrostatic piezoelectric coefficients d h (1) and d′ h (3) , were measured, d h (1) =(244±3) pC/N and d′ h (3) =(92±1) pC/N. The hydrostatic piezoelectric coefficient d h (3) for orthogonal axis system was calculated to be d h (3) =(87±2) pC/N. The, optimal orientation of the sample has been found as (Xy l)−20°-cut. Maximal value of the effective hydrostatic piezoelectric coefficient d h (1) equals 260 pC/N. Double rotated samples were also studied. The orientation of the samples insensitive to the pressure has been found. The theoretical mean value of hydrostatic piezoelectric coefficient (d h ) mean corresponding to randomly oriented Sn2P2S6 grains in a poled composite has been calculated to be (d h ) mean =136 pC/N.  相似文献   
109.
110.
The function lattice, or generalized Boolean algebra, is the set of ℓ-tuples with the ith coordinate an integer between 0 and a bound ni. Two ℓ-tuples t-intersect if they have at least t common nonzero coordinates. We prove a Hilton–Milner type theorem for systems of t-intersecting ℓ-tuples.Received September 29, 2004  相似文献   
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