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41.
42.
Forrer J Schmutz H Tschaggelar R Schweiger A 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,166(2):220-251
Direct detection of free induction decays and electron spin echoes, and the recording of echo-detected EPR spectra and electron spin echo envelope modulation patterns at a microwave frequency of 2.5 GHz is demonstrated. This corresponds to the measurement of the transverse magnetization in the laboratory frame, rather than in the rotating frame as usually done by down-converting the signal (homodyne detection). An oscilloscope with a 6-GHz analog bandwidth, a sampling rate of 20 GigaSamples per second, and a trigger frequency of 5 GHz for the edge trigger and 750 MHz for the advanced trigger, is used in these experiments. For signal averaging a 3-GHz microwave clock divider has been developed to synchronize the oscilloscope with the frequency of the EPR signal. Moreover, direct detection of continuous wave EPR signals at 2.5 GHz is described. 相似文献
43.
Rene L. Schilling 《Integral Equations and Operator Theory》2001,41(1):74-92
Let (A, D(A)) denote the infinitesimal generator of some strongly continuous sub-Markovian contraction semigroup onL
p
(m), p1 andm not necessarily -finite. We show under mild regularity conditions thatA is a Dirichlet operator in all spacesL
q
(m), qp. It turns out that, in the limitq,A satisfies the positive maximum principle. If the test functionsC
c
D(A), then the positive maximum principle implies thatA is a pseudo-differential operator associated with a negative definite symbol, i.e., a Lévy-type operator. Conversely, we provide sufficient criteria for an operator (A, D(A)) onL
p(m) satisfying the positive maximum principle to be a Dirichlet operator. If, in particular,A onL
2
(m) is a symmetric integro-differential operator associated with a negative definite symbol, thenA extends to a generator of a regular (symmetric) Dirichlet form onL
2
(m) with explicitly given Beurling-Deny formula. 相似文献
44.
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46.
A Riesz space E is said to have the b-property if each subset that is order bounded in the bidual remains to be order bounded in E. Properties of a Riesz space with the b-property, the relationship between the b-property and various classes of operators are studied. 相似文献
47.
The structural and magnetic evolution in magnesium ferrite (MgFe2O4) caused by high-energy milling is investigated by Mössbauer spectroscopy. 相似文献
48.
H. Alt 《Fresenius' Journal of Analytical Chemistry》1892,31(1):349-350
Ohne Zusammenfassung 相似文献
49.
Rene Y. Darmon 《The Journal of the Operational Research Society》1987,38(12):1121-1132
This paper describes an IBM-PC menu-driven and user-friendly procedure which can help sales management in setting up optimal quota-bonus plans. For a given sales force, the resulting quotabonus plan maximizes the firm's current profits subject to (1) keeping every individual sales-force member at least at his/her current level of satisfaction (or eventually, increasing this level), and (2) being consistent and harmonious across sales representatives. The QUOPLAN system is composed of two submodels. The first submodel is used by salespersons for eliciting their own utility functions, and is essentially based upon the principles of conjoint analysis. The second submodel is used by management for reconciling all the individuals' judgements and the company's objectives into a consistent quota-bonus plan. 相似文献
50.
Summary We give a general construction of infinite dimensional Ornstein-Uhlenbeck processes. We present expansions of these processes based on the expansion of the covariance operators in generalized eigenfunctions, and we answer positively some question left open by J.B. Walsh on properties of the hitting times of these processes.Partially supported by NSF-Grant MCS 8202045 相似文献