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991.
Summary The limiting behavior of one-dimensional diffusion process in an asymptotically self-similar random environment is investigated through the extension of Brox's method. Similar problems are then discussed for a random walk in a random environment with the aid of optional sampling from a diffusion model; an extension of the result of Sinai is given in the case of asymptotically self-similar random environments.  相似文献   
992.
Beta-BaGeO3, being high-temperature form, are formed metastably at 630-660 °C from an amorphous material prepared by the simultaneous hydrolysis of barium and germanium alkoxides. The transformation of BaGeO3 can be summarized as follows; amorphous BaGeO3
melt. On cooling from the melt, β- BaGeO3 can be retained at room temperature.  相似文献   
993.
994.
Arenediazonium tetrafluoroborates (ArN2BF4 where Ar=Ph, 4-MeC6H4, 4-BrC6H4, 4-IC6H4 and 4-NO2C6H4) reacted easily with CH2=CHSiMe3 at 25 δC to give ArCH=CH2, (E-ArCH=CHSiMe3 and Ar(Me3Si)C=CH2 in excellent yields under palladium(O) catalysis. (E)-ArCH=CHSiMe3 compounds were obtained predominantly and isolated in good yields by using an excess of CH2=CHSiMe3 over ArN2BF4. Protodesilylation of the reaction mixture afforded styrene derivatives.  相似文献   
995.
Thin iron oxides deposited on semi-conductive glass by a spray pyrolysis technique were analysed by Conversion Electron Mössbauer Spectrometry (CEMS). Iron oxide deposited on SnO2 coated glass was composed of a large grained particles of crystalline α?Fe2O3, which showed sextet. The doublet and sextet appeared in CEM spectra of iron oxides deposited on In2O3 and WO3 coated glasses. The sextet was due to α?Fe2O3 and the doublet was attributted to the superparamagnetic microcrystalline α?Fe2O3 (≈15nm) rather than to spinel compounds of iron. The iron oxide deposited on ZnO coated glass gave a doublet in CEM spectra. It was supporsed to be due to very fine particle of α?Fe2O3 (<100nm). It was found that iron oxide films obtained by spray pyrolysis were dependent on the kinds and the temperature of the semi-conductive materials coated on glass.  相似文献   
996.
997.
Let X be a nonsingular conservative one-dimensional periodic diffusion process, λ0 its principal eigenvalue and X a binary splitting branching diffusion process with nonbranching part X. For each α > λ0 we have two positive martingales Wit(α), i = 1, 2, of X attached to the two positive α-harmonic functions of X. The main purpose of this paper is to show that their limit random variables are positive for all α? (λ0, αi), where αi are some constants greater than λ0.  相似文献   
998.
1,4,8,11,15,18,22,25-Octaalkoxy-2,3,9,10,16,17,23,24-octakis(phenylthio)phthalocyaninato copper(II) was synthesized. They were easily soluble in organic solvents and their Q-bands showed bathochromic shifts about 100 nm compared with unsubstituted phthalocyaninato copper(II). Their properties were examined.  相似文献   
999.
1000.
A graph G is said to be decomposable if G can be decomposed into a cartesian product of two nontrivial graphs. G is bidecomposable if not only G but also its complement G is decomposable. We prove that there are only six bidecomposable graphs; 2K(2), C4, Q 3, K(2) ×(K(2) + K(2)) , K(3) × K(3).  相似文献   
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