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1.
Herman Winick 《Synchrotron Radiation News》2015,28(4):26-27
I am indebted to Karl Brown for suggesting that I invite Klaus, who I did not know at the time, to a workshop on wiggler magnets in March 1977. I recall Karl saying to me something like, “Herman, if you want someone who knows about magnets, you should invite Klaus Halbach.” Klaus came and even made a contribution about some aspects of the design of electromagnet wigglers, the only type of wigglers that had been considered to that time. However, it was at that workshop that Klaus got his introduction to synchrotron radiation, mostly by listening to talks by Albert Hofmann and Andy Sesler, who explained the marvelous properties of undulator magnets as radiation sources. Klaus filed this information in his long-term memory banks while working on other topics, particularly the design of permanent magnet quadrupoles for proton linacs. 相似文献
2.
O. Perru F. Ibrahim O. Bajeat C. Bourgeois F. Clapier E. Cottereau C. Donzaud M. Ducourtieux S. Galès D. Guillemaud-Mueller C. Lau H. Lefort F. Le Blanc A. C. Mueller J. Obert N. Pauwels J. C. Potier F. Pougheon J. Proust B. Roussière J. Sauvage O. Sorlin D. Verney 《Physics of Atomic Nuclei》2003,66(8):1421-1427
The PARRNe facility has been used to produce neutron-rich isotopes 83,84Gaby the ISOL method. Their decay has been studied, and β-γ coincidence and γ-γ coincidence data were collected as a function of time. The first two excited levels in 83Ge and the first excited level in 84Ge have been measured for the first time. 相似文献
3.
4.
L. Pillier C. Moreau X. Mercier J.F. Pauwels P. Desgroux 《Applied physics. B, Lasers and optics》2002,74(4-5):427-434
Cavity ring-down spectroscopy (CRDS) is used to measure the NO mole fraction formed in the burnt gases of low-pressure premixed
flames. It is shown that the line-of-sight absorption is greatly increased by the contribution of the NO molecules surrounding
the burner. This contribution has been quantified by developing a mathematical procedure taking into account the spatial and
spectral features of the CRDS measurement. Calculations have been undertaken in the general case of a stable species not consumed
in the flame. The most sensitive parameter is the temperature both in the flame and outside the flame. Simulations allow the
selection of the best spectroscopic transitions for a given flame (i.e. a given temperature profile), ensuring the weakest
influence of the inaccuracy affecting the temperature determination. High quantum states belonging to the A–X (0–1) band of
NO have been found to be the most valuable and have led to a NO mole fraction determination with an accuracy of ±13%. NO absorption
in the flame was completely masked using the A–X (0–0) band. Finally, the prompt-NO mole fraction formed in a methane/air
flame stabilized at 33 Torr is obtained by combining CRDS and laser induced fluorescence techniques.
Received: 12 October / Revised version: 1 February 2002 / Published online: 14 March 2002 相似文献
5.
We demonstrate how optimization problems arise in the field of pattern classification, in particular in using piecewise-linear classification and classification based on an optimal linear separator. We motivate the need in this area for a general purpose optimization approach. We discuss ALOPEX, a biased random search approach, from the point of view of this need. While ALOPEX itself failed to fulfil our need, a newly-introduced generalization of it (iterated ALOPEX) was found to be appropriate for the optimization problems of our particular concern. We conclude the paper with a brief critical evaluation of this approach as compared to our original aims. 相似文献
6.
Robbert Dijkgraaf Erik Verlinde Herman Verlinde 《Communications in Mathematical Physics》1988,115(4):649-690
We study the theory ofc=1 torus and 2-orbifold models on general Riemann surfaces. The operator content and occurrence of multi-critical points in this class of theories is discussed. The partition functions and correlation functions of vertex operators and twist fields are calculated using the theory of double covered Riemann surfaces. It is shown that orbifold partition functions are sensitive to the Torelli group. We give an algebraic construction of the operator formulation of these nonchiral theories on higher genus surfaces. Modular transformations are naturally incorporated as canonical transformations in the Hilbert space. 相似文献
7.
The class
of orthomodular lattices which have only finitely many commutators is investigated. The following theorems are proved:
contains the block-finite orthomodular lattices. Every irreducible element of
is simple. Every element of
is a direct product of a Boolean algebra and finitely many simple orthomodular lattices. The irreducible elements of
which are modular, or are M-symmetric with at least one atom, have height two or less. 相似文献
8.
Kommareddi Nagesh S. Tata Murthy Karayigitoglu Cigdem John Vijay T. McPherson Gary L. Herman Michael F. O'Connor Charles J. Lee Young-Sook Akkara Joseph A. Kaplan David L. 《Applied biochemistry and biotechnology》1995,51(1):241-252
Applied Biochemistry and Biotechnology - Horseradish peroxidase has been used as a biocatalyst to synthesize a polymeric material from alkyl-substituted phenols. The synthesis is carried out in a... 相似文献
9.
Electrical resistivity (4.2–800°K) and magnetic susceptibility (4.2–500°K) measurements are carried out on Cu3–xAs, Cu5–xAs2 and the recently obtained, tetragonal Cu2As. All three compounds appear to be metallic conductors, but have high residual resistances because of the large defect concentrations (resulting from non-stoichiometry and preparation method). Cu3–xAs is diamagnetic; Cu5–xAs2 is Pauli-paramagnetic; Cu2As has a very small, constant, positive susceptibility above room temperature and a more pronounced Curie-Weiss behaviour at lower temperatures. The Pauli-paramagnetic contributions have been estimated. A slight anomaly in the electric and magnetic behaviour of Cu3–xAs is observed at 220°K. To clarify the high-temperature phenomena, a series of D.T.A. and X-ray experiments has also been carried out. 相似文献
10.
A stable nitronic acid, 2-aci-nitro-1,3-propanediol, may be prepared from nitromethane and paraformaldehyde under fluoride ion catalysis. 相似文献