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91.
Adam Bartoszek Paweł G. Walczak Szymon M. Walczak 《Bulletin of the Brazilian Mathematical Society》2014,45(1):179-195
We study the order of tangency of surfaces and Dupin cyclides. We show that generically the maximal tangency order equals 4 and provide a number of examples. 相似文献
92.
White Light Emissive DyIII Single‐Molecule Magnets Sensitized by Diamagnetic [CoIII(CN)6]3− Linkers
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Dr. Szymon Chorazy Dr. Michał Rams Dr. Koji Nakabayashi Prof. Dr. Barbara Sieklucka Prof. Dr. Shin‐ichi Ohkoshi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(22):7371-7375
The self‐assembly of DyIII–3‐hydroxypyridine (3‐OHpy) complexes with hexacyanidocobaltate(III) anions in water produces cyanido‐bridged {[DyIII(3‐OHpy)2(H2O)4] [CoIII(CN)6]}?H2O ( 1 ) chains. They reveal a single‐molecule magnet (SMM) behavior with a large zero direct current (dc) field energy barrier, ΔE=266(12) cm?1 (≈385 K), originating from the single‐ion property of eight‐coordinated DyIII of an elongated dodecahedral geometry, which are embedded with diamagnetic [CoIII(CN)6]3? ions into zig‐zag coordination chains. The SMM character is enhanced by the external dc magnetic field, which results in the ΔE of 320(23) cm?1 (≈460 K) at Hdc=1 kOe, and the opening of a butterfly hysteresis loop below 6 K. Complex 1 exhibits white DyIII‐based emission realized by energy transfer from CoIII and 3‐OHpy to DyIII. Low temperature emission spectra were correlated with SMM property giving the estimation of the zero field ΔE. 1 is a unique example of bifunctional magneto‐luminescent material combining white emission and slow magnetic relaxation with a large energy barrier, both controlled by rich structural and electronic interplay between DyIII, 3‐OHpy, and [CoIII(CN)6]3?. 相似文献
93.
Utko J Przybylak S Jerzykiewicz LB Szafert S Sobota P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(1):181-190
Reactions of [Mg(thffo)(2)] (1) or [Ca(thffo)(2)] (2) with ZrCl(4) or HfCl(4) in a CH(2)Cl(2)/THF/CH(3)CN mixture give thermally stable neutral heterobimetallic tetranuclear complexes [M(3)M'(mu(x)-O)(mu,eta(2)-thffo)(6)(Cl)(6)] (thffo=tetrahydrofurfuroxide; M/M'/x: 3, Zr/Mg/3; 4, Hf/Mg/3; 5, Zr/Ca/4; 6, Hf/Ca/4) as colorless crystals in 75-82 % yield. X-ray diffraction studies show complexes 3-5 to contain oxo-bridged M(3) triangles that are capped by an alkaline earth metal-containing moiety to form species of C(3) symmetry. Reactions of ZrCl(4) and HfCl(4) with pure tetrahydrofurfuryl alcohol in EtOH and MeOH provide ionic complexes [M(3)(mu(3)-O)(mu,eta(2)-thffo)(3)(L)(3)(Cl)(6)]Cl (M/L: 8, Zr/EtOH; 9, Hf/EtOH; 10, Zr/MeOH) in 66-79 % yield. Complexes 8-10 consist of M(3) triangles that are analogous to those in 3-6 and possess similar overall symmetry, as shown by X-ray crystallography. Changes in the reaction conditions afforded the asymmetric neutral dimer [Zr(2)(mu-thffo)(2)(thffoH)(Cl)(6)] (7) and the homometallic [Zr(3)(mu(3)-O)(mu,eta(2)-thp)(3)(thf)(2)(Cl)(7)] (11). 相似文献
94.
Szymon Pliś 《Journal of Geometric Analysis》2016,26(4):2503-2518
We define the Monge–Ampère operator \({(i\partial {\bar{\partial }}u)^{2}}\) for continuous J-plurisubharmonic functions on four dimensional almost complex manifolds. 相似文献
95.
Przybylak SW Tuna F Teat SJ Winpenny RE 《Chemical communications (Cambridge, England)》2008,(17):1983-1985
Synthetic, structural and magnetic studies of a new Fe(II) single chain magnet are reported. 相似文献
96.
Szymon G?a?b 《Journal of Mathematical Analysis and Applications》2008,343(2):835-841
Let H⊂C[0,1] stand for the Polish space of all increasing autohomeomorphisms of [0,1]. We show that the family of all strictly singular autohomeomorphisms is -complete. This confirms a suggestion of Graf, Mauldin and Williams. Some related results are also included. 相似文献
97.
Szymon Plis 《Proceedings of the American Mathematical Society》2008,136(12):4355-4364
We prove the regularity for some complex Monge-Ampère equations with boundary data equal to .
98.
Szymon Dolecki Alojzy Lechicki 《Journal of Mathematical Analysis and Applications》1982,88(2):547-554
The refinement of a Choquet theorem on (strong) upper semi-continuity and its relation to the Vainstein lemma are dealt with here. Relevance of subcontinuity is discussed. Consequently, an improvement of a characterization theorem of Dolecki and Rolewicz is achieved. 相似文献
99.
100.
Stanisław Leśniak Michał Rachwalski Szymon Jarzyński Emilia Obijalska 《Tetrahedron: Asymmetry》2013,24(20):1336-1340
A straightforward synthetic route to a series of new catalysts bearing secondary hydroxyl and aziridine moieties as nucleophilic centers built on the chiral skeleton of (S)-(+)-lactic acid is described. All of the new compounds have been tested in the enantioselective addition of diethyl- and phenylethynylzinc to aryl and alkyl aldehydes, yielding the corresponding chiral alcohols in high chemical yields (up to 85%) and good ee’s of approximately 85%. The influence of the stereogenic center located at the aziridine subunit on the stereochemical outcome is also discussed. 相似文献