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971.
Scott Brownridge Jack Passmore Gabriele Schatte 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):483-484
Abstract I4 2+ is the only known cyclic homopolyatomic cation or anion of iodine. It has a rectangular planar structure which may be thought of as containing two I2 + units joined by a weak π?-π? 4 centre 2 electron bond.1 In this paper we report our FT-Raman spectra of I4 2+, which conflict with those published by Gillespie et al. 1 and present evidence that the peaks attributed to a species containing iodine in the +1 oxidation state are in fact due to I4 2+. 相似文献
972.
Mariella Cecchi Mauro Marini Gabriele Villari 《NoDEA : Nonlinear Differential Equations and Applications》2009,6(2):173-190
((without abstract.)) 相似文献
973.
Uri Admon David Donohue Helmut Aigner Gabriele Tamborini Olivier Bildstein Maria Betti 《Microscopy and microanalysis》2005,11(4):354-362
Physical, chemical, and isotopic analyses of individual radioactive and other particles in the micron-size range, key tools in environmental research and in nuclear forensics, require the ability to precisely relocate particles of interest (POIs) in the secondary ion mass spectrometer (SIMS) or in another instrument, after having been located, identified, and characterized in the scanning electron microscope (SEM). This article describes the implementation, testing, and evaluation of the triangulation POIs re-location method, based on microscopic reference marks imprinted on or attached to the sample holder, serving as an inherent coordinate system. In SEM-to-SEM and SEM-to-SIMS experiments re-location precision better than 10 microm and 20 microm, respectively, is readily attainable for instruments using standard specimen stages. The method is fast, easy to apply, and facilitates repeated analyses of individual particles in different instruments and laboratories. 相似文献
974.
Bartolo Gabriele Giuseppe Salerno Gian Paolo Chiusoli 《Journal of organometallic chemistry》2003,687(2):219-228
A simple catalytic system, consisting of PdI2 in conjunction with an excess of KI, has proven to be very valuable for the direct one-step synthesis of a variety of heterocyclic derivatives by oxidative carbonylation of suitably functionalized alkynes. The same catalyst also promoted the oxidative carbonylation of β-amino alcohols to oxazolidin-2-ones with unprecedented catalytic efficiencies for this kind of reaction. 相似文献
975.
976.
Richard K. Haynes Burkhard Fugmann Jrg Stetter Karl Rieckmann Hans‐Dietrich Heilmann Ho‐Wai Chan Man‐Ki Cheung Wai‐Lun Lam Ho‐Ning Wong Simon L. Croft Livia Vivas Lauren Rattray Lindsay Stewart Wallace Peters Brian L. Robinson Michael D. Edstein Barbara Kotecka Dennis E. Kyle Bernhard Beckermann Michael Gerisch Martin Radtke Gabriele Schmuck Wolfram Steinke Ute Wollborn Karl Schmeer Axel Rmer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2006,118(13):2136-2142
977.
In this paper we prove a result on the existence of periodic motions for the periodically forced Liénard differential equation
x
″+f(x)x
′+g(x)=e(t) in a situation where the phase portrait of the associated autonomous equation is similar to that of a centre limited by
an unbounded separatrix. The existence result, which is based on a degree theoretic continuation theorem, enables us to treat
some interesting cases not previously considered in the literature.
Received: April 27, 2000 Published online: December 19, 2001 相似文献
978.
Staubmann Ruth Foidl Gabriele Foidl Nikolaus Gübitz Georg M. Lafferty Robert M. Valencia Arbizu Victoria M. Steiner Walter 《Applied biochemistry and biotechnology》1997,63(1):457-467
Applied Biochemistry and Biotechnology - Seeds of the tropical plantJatropha curcas (purge nut, physic nut) are used for the production of oil. Several methods for oil extraction have been... 相似文献
979.
Yuri V. Rogovchenko Gabriele Villari 《NoDEA : Nonlinear Differential Equations and Applications》1997,4(2):271-282
For a class of second order nonlinear autonomous differential equations asymptotic properties of the solutions as are studied. The investigation is done in the phase plane and the phase portrait of the equivalent system is obtained by
using the zero-isocline function. Some suffcient conditions are presented which for the case of Liénard equation become also
necessary.
Received December 21, 1995 相似文献
980.