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61.
Orewczyk J. Jasieńska S. Iwanczenko S. 《Journal of Thermal Analysis and Calorimetry》1998,54(1):79-84
This paper presents applications of thermal analysis to observe the course of reduction of acidic pellets, metallurgical substances
whose reducibility and strength are basic parameters of use in blast furnace processes. Both parameters depend on the mineral
composition of the samples. The investigations included determination of the chemical and phase compositions of the initial
samples and reduction products.
Research was conducted on acidic pellets from Połtawa (Poland), applied in the T. Sendzimir Steelworks (Poland), in comparison
with pellets from Brazil, Canada and Lebedyn (Russia).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
62.
Grega Cigler Roman Drnovšek Damjana Kokol-Bukovšek Matja? Omladi? Thomas J. Laffey Heydar Radjavi Peter Rosenthal 《Journal of Functional Analysis》1998,160(2):245
T. Laffey showed (Linear and Multilinear Algebra6(1978), 269–305) that a semigroup of matrices is triangularizable if the ranks of all the commutators of elements of the semigroup are at most 1. Our main theorem is an extension of Hthis result to semigroups of algebraic operators on a Banach space. We also obtain a related theorem for a pair {A, B} of arbitrary bounded operators satisfying rank (AB−BA)=1 and several related conditions. In addition, it is shown that a semigroup of algebraically unipotent operators of bounded degree is triangularizable. 相似文献
63.
64.
Alexei A. Belik Andrei V. Mironov Roman V. Shpanchenko Eiji Takayama‐Muromachi 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(7):i37-i39
The crystal structure of a new high‐pressure modification of cadmium divanadium hexaoxide, CdV2O6, was refined from X‐ray single‐crystal data. It contains zigzag chains of edge‐sharing VO6 octahedra. Octahedra in adjacent chains share corners and form corrugated layers. Octahedrally coordinated Cd atoms, which lie on twofold axes, are situated between the layers. The columbite‐like structure results in a strong distortion of the CdO6 octahedra which may be stabilized only at high pressure. 相似文献
65.
Zbigniew Peradzyński Bogdan Kazmierczak 《Archive of Applied Mechanics (Ingenieur Archiv)》2005,74(11-12):827-833
The influence of mechano-chemical coupling on calcium concentration waves is considered. The propagation of calcium waves is described by a reaction–diffusion equation with the reaction term dependent on the mechanical stress responsible for the release of calcium. Similarly the balance of mechanical forces is influenced by the calcium concentration through the so-called traction force. 相似文献
66.
Dealing with infinite iterated function systems we introduce and develop the ergodic theory of Hölder systems of functions similarly as in [HU] and [HMU]. In the context of conformal infinite iterated function systems we prove the volume lemma for the Hausdorff dimension of the projection onto the limit set of a shift invariant measure. This can be considered as a Billingsley type result. Our cenral goal is to demonstrate the appearance of the "singularity-absolute continuity" dichotomy for equilibrium states of Hölder systems of functions which has been observed in [PUZ,I] and [PUZ,II] (see also [DU1] and [DU2]) in the setting of rational functions of the Riemann sphere. 相似文献
67.
X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) have been used to investigate the effect of reactive ion etching (RIE) on poly(methylhydrogensiloxane-co-dimethylsiloxane) surface in fluorine-based plasmas. Polysiloxane layers supported on the standard silicon wafers were etched using SF6 + O2 or CF4 + O2 plasmas. SEM studies show that the polysiloxane morphology depends on plasma chemical composition strongly. Presence of a columnar layer likely covered with a fluorine rich compound was found on the elastomer surface after the CF4 + O2 plasma exposure. After the SF6 + O2 or CF4 + O2 plasma treatment the polysiloxane surface enriches with fluorine or with fluorine and aluminum, respectively. Different morphologies and surface chemical compositions of the silicone elastomer etched in both plasmas indicate different etching mechanisms. 相似文献
68.
69.
The stoichiometric reactions of trimethylaluminum with 2,6‐(MeOCH2)2C6H3OH (LH) revealed compounds L3Al ( 1 ) and L2AlMe ( 2 ). On the other hand reaction of 1 equiv. of LH with trimethylaluminum did not lead to the formation of complex LAlMe2 ( 3 ), rather 2 together with Me3Al were observed as a result of a disproportionation of 3 . Compounds 1 and 2 were characterized by elemental analysis, 1H and 13C NMR spectroscopy and in the case of 1 by X‐ray diffraction. Derivative 2 underwent transmetalation with Ph3SnOH, giving LSnPh3 ( 4 ) as the result of a migration of ligand L from the aluminum to the tin atom. The identity of 4 was established by elemental analysis, 1H, 13C and 119Sn NMR spectroscopy and 1H, 119Sn HMBC experiments. The system 2 and B(C6F5)3 in a 1:1 molar ratio was shown to be active in the polymerization of propylene oxide and ε‐caprolactone. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
70.
We describe phenomena occurring just before a saddle-node bifurcation for one-parameter families of interval maps. In particular, as a parameter approaches the bifurcation value, attracting periodic orbits of periodsk, k+1,k+2,k+3,... can appear. We make a detailed study of a family of cusp-shaped maps, where this phenomenon occurs in a pure form. 相似文献