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21.
22.
Tim Bedford 《Constructive Approximation》1989,5(1):33-48
We consider some self-affine fractal functions previously studied by Barnsleyet al. The graphs of these functions are invariant under certain affine scalings, and we extend their definition to allow the use of nonlinear scalings. The Hölder exponent,h, for these fractal functions is calculated and we show that there is a larger Hölder exponent,h
, defined at almost every point (with respect to Lebesgue measure). For a class of such functions defined using linear affinities these exponents are related to the box dimensionD
B of the graph byh2–D
Bh
.Communicated by Michael F. Barnsley. 相似文献
23.
24.
Charles Brown R. Harry Cragg Tim J. Miller David O''N. Smith 《Journal of organometallic chemistry》1981,220(3):C25-C26
The application of variable temperature 13C NMR to the study of a series of chlorodialkylaminophenylboranes has enabled G values for the rotational barrier, about the boron---nitrogen bond, to be determined. 相似文献
25.
M. Weber N. Trautmann H. Menke G. Herrmann und N. Kaffrell 《Fresenius' Journal of Analytical Chemistry》1973,267(3):192
Ohne ZusammenfassungDie ausführliche Veröffentlichung erfolgt in Radiochimica Acta [3]. 相似文献
26.
Ronny Kleinhempel Gunar Kaune Matthias Herrmann Hartmut Kupfer Walter Hoyer Frank Richter 《Mikrochimica acta》2006,156(1-2):61-67
Indium tin oxide (ITO) thin films were deposited by mid frequency pulsed dual magnetron sputtering using a metallic alloy
target with 10 wt.% tin in an atmosphere of argon and oxygen. The aim of the work was to study the interdependence of structural,
electrical and optical properties of ITO films deposited in the reactive and transition target mode, respectively. The deposition
rate in the transition mode exceeds the deposition rate in the reactive mode by a factor of six, a maximum value of 100 nm·m min−1 could be achieved. This corresponds to a static deposition rate of 200 nm min−1. The lowest electrical resistivity of 1.1·10−3 Ω cm was measured at samples deposited in the high oxygen flow range in the transition mode. The samples show a good transparency
in the visible range corresponding to extinction coefficients being below 10−2. X-ray diffraction was used to characterise crystalline structure as well as film stress. ITO films prepared in the transition
mode show a slightly preferred orientation in (211) direction, whereas films deposited in the reactive mode are strongly (222)
oriented. Compared to undoped In2O3 all samples have an enlarged lattice. The lattice strain perpendicular to the surface is about 0.8% and 2.0% for films grown
in the transition and the reactive mode, respectively. Deposition in the transition mode introduces a biaxial film stress
in the range of −300 MPa, while stress in reactive mode samples is −1500 MPa. 相似文献
27.
M. Jonathan Fray Paul Allen Paul R. Bradley Clare E. Challenger Michael Closier Tim J. Evans Mark L. Lewis John P. Mathias Carly L. Nichols Yvonne M. Po-Ba Hayley Snow Mark H. Stefaniak Hannah V. Vuong 《Tetrahedron》2006,62(29):6869-6875
The synthesis of ten substituted aminomethylene tetrahydro-isoquinolines is described, proceeding in eight steps from 5-hydroxyisoquinoline via reductive amination of N-Boc tetrahydro-isoquinoline 5-carboxaldehyde. Likewise, reductive amination was used to prepare four substituted dihydro-isoindoles from the corresponding aldehyde. The dihydro-isoindole ring system was conveniently accessed via a 2+2+2 cycloaddition reaction. 相似文献
28.
Wolfgang A. Herrmann Gerhard M. Lobmaier Martina Elison 《Journal of organometallic chemistry》1996,520(1-2):231-234
Oxometal complexes of molybdenum and tungsten in high oxidation states from stable adducts with 1,3-dimethylimidazoline-2-ylidene (L) 1. The first ‘carbene’ complexes of molybdenum(VI) [MoO2Cl(L)3]Cl (3a) and tungsten(VI) WO2Cl2(L)2 (4b) are reported. 相似文献
29.
30.
Tim D. Cochran 《Inventiones Mathematicae》1987,90(3):635-645
Summary We show that each of a sequence of concordance invariants for codimension-two links of spheres inS
n+2
, defined by Kent Orr, is identically zero forn>1. For classical links (n=1), the same proof shows that these invariants vanish if and only if Milnor's
vanish (a result obtained independently and earlier by Orr himself). We offer sufficient conditions for the vanishing of Orr's -invariant (not covered by the above). We discuss how this relates to positive results.Supported by a National Science Foundation Postdoctoral Fellowship and the hospitality of Univ. Calif. San Diego Math. Dept. 相似文献