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141.
Zöller T Iovkova-Berends L Berends T Dietz C Bradtmöller G Jurkschat K 《Inorganic chemistry》2011,50(17):8645-8653
The syntheses and molecular structures of the intramolecularly coordinated tin(II) compounds {CH(2)N(Me)CH(Me)CH(Ph)O}(2)SnL (2, L = lone pair; 4, L = W(CO)(5); 5, L = Cr(CO)(5)) and of the related hydroxido-substituted tin(IV) compound [{CH(2)N(Me)CH(Me)CH(Ph)O}(2)Sn(OH)](2)O, 6a, are reported. Also reported are the molecular structures of the enantiopure N,N'-ethylenebis-(1R,2S)-ephedrine, {CH(2)N(Me)CH(Me)CH(Ph)OH}(2) (1), and its hydrobromide {CH(2)N(Me)CH(Me)CH(Ph)OH}(2)·HBr (1a). 相似文献
142.
Sweeney CM Nehl CL Hasan W Liang T Eckermann A Meade TJ Odom TW 《The journal of physical chemistry. C, Nanomaterials and interfaces》2011,115(32):15933-15937
A three-channel spectrometer (3CS) based on a commercial digital camera was developed to distinguish among tens of large (>100 nm), anisotropic plasmonic particles with various shapes, orientations, and compositions on a surface simultaneously. Using band pass filters and polarizers, the contrast of 3CS images could be enhanced to identify specific orientation and composition characteristics of gold and gold-silver nanopyramids and as well as the direction of the longest arm of gold nanostars. 相似文献
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144.
Robert Vestberg Christina Nilsson Cesar Lopes Per Lind Bertil Eliasson Eva Malmstrm 《Journal of polymer science. Part A, Polymer chemistry》2005,43(6):1177-1187
The synthesis and characterization of dendron‐coated 2,5‐bis(phenylethynyl)thiophene chromophores are described. The dendrimers were grown divergently on the arylthiophene core with the versatile anhydride of 2,2‐bis(methylol)propionic acid. The arylthiophene core was synthesized with Sonogashira coupling reactions. Structurally well‐defined dendrimers up to the fourth generation were grown, as confirmed by size exclusion chromatography, NMR, and matrix‐assisted laser desorption/ionization time‐of‐flight analysis. The different dendritic substitution did not influence the absorption spectra of the compounds in or near the visible region. Solutions of arylthiophenes had good transparency at wavelengths greater than 400 nm. The dendritic thiophenes exhibited an optical‐power limit at the laser wavelength of 532 nm. However, the magnitude of the optical‐power limit of these compounds was slightly lower than that of a nondendritic arylthiophene with n‐pentyl substituents. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1177–1187, 2005 相似文献
145.
Shing Horng Lee Christina F. Jou Chien Ping Lee Cheng Chi Hu 《International Journal of Infrared and Millimeter Waves》1997,18(10):2001-2017
A simple varactor tuned X-band Gunn diode VCO antenna array which is strongly coupled has been demonstrated. These arrays
have the advantages of simple biasing circuit, no resistors required to eliminate multimode problem and suitable for monolithic
integration circuit. Preliminary results show a maximum tuning range of 47MHz for 1×1 array and 170MHz for 2×2 array. In order
to solve power combining heating problem, we move the backside metal forward and it becomes a microstrip form. The measured
frequency and radiation patterns of these grid arrays agree very well with theoretical calculations. 相似文献
146.
Wilfried Imrich J.M.S Simões-Pereira Christina M Zamfirescu 《Journal of Combinatorial Theory, Series B》1984,36(1):1-15
This paper extends previous results of the authors. In particular, non-treerealizable metrics are investigated and it is shown that every finite metric has an optimal realization by a graph. 相似文献
147.
Christina Bauer 《Geometriae Dedicata》1996,62(2):179-192
We give a new proof for the existence and uniqueness (up to translation) of plane minimal pairs of convex bodies in a given equivalence class of the Hörmander-R»dström lattice, as well as a complete characterization of plane minimal pairs using surface area measures. Moreover, we introduce the so-called reduced pairs, which are special minimal pairs. For the plane case, we characterize reduced pairs as those pairs of convex bodies whose surface area measures are mutually singular. For higher dimensions, we give two sufficient conditions for the minimality of a pair of convex polytopes, as well as a necessary and sufficient criterion for a pair of convex polytopes to be reduced. We conclude by showing that a typical pair of convex bodies, in the sense of Baire category, is reduced, and hence the unique minimal pair in its equivalence class. 相似文献
148.
W.Russell Bowman David S. Brown Christina T.W. Leung Andrew P. Stutchbury 《Tetrahedron letters》1985,26(4):539-540
X-Ray crystallography has been used to determine the unusual cyclopropyl structure for the product of the SRNl reaction between the anion of 2-nitropropane and 3-bromo-1-nitrocyclohex-1-ene. 相似文献
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