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81.
Ohne Zusammenfassung 相似文献
82.
R. Havermann G. Groscurth L. Seekles X. Thiesse M. Verain A. Ziegler und J. A. Pierce 《Fresenius' Journal of Analytical Chemistry》1937,111(2-4):159-160
Ohne Zusammenfassung 相似文献
83.
Pingsheng Zhang Miall Cedilote Thomas P. Cleary Michael E. Pierce 《Tetrahedron letters》2007,48(49):8659-8664
Aromatic compounds bearing a basic nitrogen atom can be converted to the corresponding nitric acid salts. Mono-nitration of the compounds can be carried out by adding a dichloromethane solution of the salts to sulfuric acid, or by adding acetyl chloride (or trifluoroacetic anhydride) to a dichloromethane solution of the salts. This protocol provides, among other benefits, the most convenient and reliable way for the prevention of over-/under-nitration and is especially suitable for scale-up. 相似文献
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Assignment of oxime and hydrazone configuration using 1H‐15N and 13C‐15N coupling measurements at natural abundance
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Measurement of 1H‐15N and 13C‐15N coupling constants at natural abundance is demonstrated to be a reliable and generic method to determine the configuration of oximes, hydrazines, and related systems. Data on 1H‐15N and 13C‐15N coupling constants on a variety of systems obtained at natural abundance confirm the geometric dependence of the measured 1H‐15N and 13C‐15N coupling constants. In addition, we summarize a simple “decision‐tree” for determining configuration based on practical considerations of sample quantity, solubility, and complexity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
86.
An Introduction to the Adjoint Approach to Design 总被引:1,自引:0,他引:1
Optimal design methods involving the solution of an adjoint system of equations are an active area of research in computational
fluid dynamics, particularly for aeronautical applications. This paper presents an introduction to the subject, emphasising
the simplicity of the ideas when viewed in the context of linear algebra. Detailed discussions also include the extension
to p.d.e.'s, the construction of the adjoint p.d.e. and its boundary conditions, and the physical significance of the adjoint
solution. The paper concludes with examples of the use of adjoint methods for optimising the design of business jets.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
John W. Davenport Margaret Anne Pierce 《International Journal of Mathematical Education in Science & Technology》2013,44(6):971-976
The rules of algebra are rules about classes of objects. In many cases, algebra can be viewed as algorithmic in nature. By specifically defining the class for which a rule applies and then the general outline of the rule, the guesswork can be removed from the process. Thus the student has a clearer understanding of when and how a particular rule applies. The paper describes this approach to the solution of algebraic expressions and the simplification of rational expressions. 相似文献
88.
[Structure: see text] Key reactions in a concise synthesis of an alpha-C-galactosylceramide analogue of KRN7000 include a diastereoselective alkenylalane addition to an N-tert-butanesulfinyl imine and the use of an epoxidation/carbamate ring opening sequence to install the aminodiol stereotriad. 相似文献
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