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21.
Thermal behaviour and biochemical activity of potassium-silicate-phosphate glasses modified by addition of Ca, Mg, acting
as ecological fertilisers of controlled release rate of the nutrients for plants were studied. It has been found that the
biochemical activity of silicate-phosphate glasses depends on the nature and the number of components forming the glassy framework
and is related to the thermal stability of glass demonstrated by the formation of new compounds during the process of crystallisation.
It is proved that these seemingly different properties are determined by the same parameters which are the strengths bonds
of glass network-formers and modifiers as well as their chemical affinity.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
22.
Jacek Doskocz Jadwiga Sołoducho Joanna Cabaj Mieczysław Łapkowski Sylwia Golba Krystyna Palewska 《Electroanalysis》2007,19(13):1394-1401
A convenient and higher yielding synthetic route to N‐alkyl‐bis(thiophene)phenothiazine derivatives is reported and their aggregation, electrochemical properties and polymerization are characterized. The key step in the synthesis of this group of compounds has been the Stille type coupling reaction between the N‐alkyldibromophenothiazine and tin derivatives of thiophene as the best way for preparation of conjugated N‐alkylphenothiazine derivatives. For this group of compounds we also present an electrochemical polymerization effect and widely adopted approach to prepare structurally ordered thin, electroconducting films by Langmuir–Blodgett technique. 相似文献
23.
David S. McGuinness Edward L. Marshall Vernon C. Gibson Jonathan W. Steed 《Journal of polymer science. Part A, Polymer chemistry》2003,41(23):3798-3803
Hetero‐bimetallic Fe(II) alkoxide/aryloxides were evaluated as initiators for the ring‐opening polymerization of rac‐lactide. [(THF)NaFe(OtBu)3]2 ( 1 ) and [(THF)4Na2Fe(2,6‐diisopropylphenolate)4] ( 2 ) (THF = tetrahydrofuran) both polymerized lactide efficiently at room temperature, with complex 1 affording better control over the molecular weight parameters of the resultant polymer. At conversions below 70%, a linear increase in molecular weight with conversion was observed, indicative of a well‐controlled polymerization process. Complex 2 is the first example of a dianionic Fe(II) alkoxide and has been structurally characterized to reveal a distorted square planar FeO4 array in which both Na counterions bridge two aryloxide ligands and are further complexed by two THF ligands. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3798–3803, 2003 相似文献
24.
We introduce here some Itô calculus for non-continuous Dirichlet processes. Such calculus extends what was known for continuous Dirichlet processes or for semimartingales. In particular we prove that non-continuous Dirichlet processes are stable under C
1 transformation. 相似文献
25.
26.
S. A. Sadovsky Yu. V. Kharlov A. L. S. Angelis E. Gładysz-Dziaduś V. L. Korotkikh G. Mavromanolakis A. D. Panagiotou 《Physics of Atomic Nuclei》2004,67(2):396-405
A phenomenological model for describing the production of Centauro events in relativistic heavy-ion collisions is discussed. The model provides quantitative predictions for kinematical variables, for the baryon number, and for the masses of a Centauro fireball and of its decay products. A Centauro fireball decays predominantly into nucleons, strange hyperons, and possibly strangelets. Centauro events in Pb + Pb collisions at the LHC energy are simulated for the CASTOR detector. The signatures of these events are discussed in detail. 相似文献
27.
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(ξ
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
28.
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
29.
P. González D. Fernández J. Pou E. García J. Serra B. León M. Pérez-Amor T. Szörényi 《Applied Physics A: Materials Science & Processing》1993,57(2):181-185
A study of the gas-phase parameters involved in ArF laser induced chemical vapour deposition of silicon-oxide thin films is presented. A complete set of experiments has been performed showing the influence of the concentration of the precursor gases, N2O and SiH4, and their influence on total and partial pressures on film growth and properties. In this paper we demonstrate the ability of this LCVD method to deposit silicon oxide films of different compositions and densities by appropriate control of gas composition and total pressure. Moreover, a material specific calibration plot comprising data obtained using different preparation techniques is presented, allowing determination of the stoichiometry of SiO
x
films by using FTIR spectroscopy independently of the deposition method. For the range of processing conditions examined, the experimental results suggest that chemical processes governing deposition take place mainly in the gas phase. 相似文献
30.
Edward Bierstone 《Inventiones Mathematicae》1997,128(2):207-302
Summary. This article contains an elementary constructive proof of resolution of singularities in characteristic zero. Our proof applies
in particular to schemes of finite type and to analytic spaces (so we recover the great theorems of Hironaka). We introduce
a discrete local invariant whose maximum locus determines a smooth centre of blowing up, leading to desingularization. To define , we need only to work with a category of local-ringed spaces satisfying certain natural conditions. If , then depends only on . More generally, is defined inductively after any sequence of blowings-up whose centres have only normal crossings with respect to the exceptional
divisors and lie in the constant loci of . The paper is self-contained and includes detailed examples. One of our goals is that the reader understand the desingularization
theorem, rather than simply “know” it is true.
Oblatum 27-VII-1995 & 30-V-1996 相似文献