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61.
D. von der Linde 《Applied Physics A: Materials Science & Processing》1973,2(6):281-296
This article reviews some aspects of the generation of very short optical pulses using mode-locked lasers, with the emphasis
laid on pulsed laser systems. Active and passive mode-locking is discussed, and the problem of measuring ultrashort light
pulses is considered. A survey of some commonly used sources and techniques for the generation of ultrashort light pulses
follows. The paper concludes with a short account of limitations in the generation and propagation of these pulses. 相似文献
62.
The ν11 infrared band of gaseous benzene C6H6 is recorded at a resolution of 0.010 cm?1. The analysis yields a number of constants, primarily B0 = 0.1897543 ± 0.0000061 cm?1 (standard error). This number is in perfect agreement with a value determined from a recent analysis of the ν1 Raman band. 相似文献
63.
Niklaus Hriger Dobrila
ivanov Horst H. A. Linde Kuno Meyer 《Helvetica chimica acta》1972,55(7):2549-2562
From the toad venom Ch'an Su the bufadienolides 1, 4, 9, 10, 12, 15, 17, 20, 22, 25 and 18 , the latter as diacetate 19 were isolated and their structure elucidated. 相似文献
64.
A.D. Linde 《Physics letters. [Part B]》1980,93(3):327-330
An interplay between vacuum structure in gauge theories and cosmology is discussed and a possible solution of the strong CP violation problem in gauge theories is suggested. 相似文献
65.
Lifshits Mikhail A.; Linde Werner; Shi Zhan 《Proceedings London Mathematical Society》2006,92(1):224-250
We investigate RiemannLiouville processes RH, with H> 0, and fractional Brownian motions BH, for 0 < H <1, and study their small deviation properties in the spacesLq([0, 1], µ). Of special interest here are thin (fractal)measures µ, that is, those that are singular with respectto the Lebesgue measure. We describe the behavior of small deviationprobabilities by numerical quantities of µ, called mixedentropy numbers, characterizing size and regularity of the underlyingmeasure. For the particularly interesting case of self-similarmeasures, the asymptotic behavior of the mixed entropy is evaluatedexplicitly. We also provide two-sided estimates for this quantityin the case of random measures generated by subordinators. While the upper asymptotic bound for the small deviation probabilityis proved by purely probabilistic methods, the lower bound isverified by analytic tools concerning entropy and Kolmogorovnumbers of RiemannLiouville operators. 2000 MathematicsSubject Classification 60G15 (primary), 47B06, 47G10, 28A80(secondary). 相似文献
66.
An integrated shape morphing and topology optimization approach based on the deformable simplicial complex methodology is developed to address Stokes and Navier‐Stokes flow problems. The optimized geometry is interpreted by a set of piecewise linear curves embedded in a well‐formed triangular mesh, resulting in a physically well‐defined interface between fluid and impermeable regions. The shape evolution is realized by deforming the curves while maintaining a high‐quality mesh through adaption of the mesh near the structural boundary, rather than performing global remeshing. Topological changes are allowed through hole merging or splitting of islands. The finite element discretization used provides smooth and stable optimized boundaries for simple energy dissipation objectives. However, for more advanced problems, boundary oscillations are observed due to conflicts between the objective function and the minimum length scale imposed by the meshing algorithm. A surface regularization scheme is introduced to circumvent this issue, which is specifically tailored for the deformable simplicial complex approach. In contrast to other filter‐based regularization techniques, the scheme does not introduce additional control variables, and at the same time, it is based on a rigorous sensitivity analysis. Several numerical examples are presented to demonstrate the applicability of the approach. 相似文献
67.
Carla Maria Mariano Fernandez Maurício Ferreira da Rosa Ana Claudia Aparecida Mariano Fernandez Wanessa de Campos Bortolucci Fabiana Borges Padilha Ferreira Giani Andrea Linde 《Natural product research》2020,34(5):731-735
AbstractThis study, was to evaluate the acaricidal effect of the essential oil (EO) and fractions (FR) obtained from Laurus nobilis leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, however FR1: sabinene (37.83%), β-pinene (13.50%), 1,8-cineole (12.66%), α-pinene (12.56%) and FR8: α-terpineol (79.19%) were highlighted as to the larvicidal potential when submitted by Larval Packet Test. The EO was tested by the Adult Immersion Test, at concentrations of 200.00; 100.00 and 50.00?µL/mL caused mortality of engorged females, egg mass reduction and hatching inhibition. Two fractions are shown to be efficient in controlling larvae FR8 (LC50?=?0.13?µL/mL, LC99?=?0.51?µL/mL) and FR1 (LC50?=?0.20?µL/mL, LC99?=?0.56?µL/mL). The fractionation of EO was determinant to elucidate which compounds were responsible for the larvicidal potential. This study opens new perspectives to direct new bioassays with the compounds obtained in the fractionation, since they present high potential on cattle tick larvae. 相似文献
68.
69.
Th. v. Fellenberg R. S. Alcock M. S. Lukjanowitsch N. P. Fedorow D. N. Bidenko E. Thomae J. Deshusses O. L. Evenson J. A. Kime S. S. Forrest Gesellschaft für Linde Eismaschinen A. S. Wetrow A. M. Kogan K. M. Nassyrowa J. P. Pusstylnikowa W. A. Gluchowzewa W. R. Tschertok Bláhá Láska E. Waser S. Janett B. Hazslinszky A. K. Fitger und CI. R. Dumble 《Fresenius' Journal of Analytical Chemistry》1938,113(5-6):226-235
Ohne Zusammenfassung 相似文献
70.
We investigate the approximation rate for certain centered Gaussian fields by a general approach. Upper estimates are proved in the context of so–called Hölder operators and lower estimates follow from the eigenvalue behavior of some related self–adjoint integral operator in a suitable L 2(μ)–space. In particular, we determine the approximation rate for the Lévy fractional Brownian motion X H with Hurst parameter H∈(0,1), indexed by a self–similar set T?? N of Hausdorff dimension D. This rate turns out to be of order n ?H/D (log?n)1/2. In the case T=[0,1] N we present a concrete wavelet representation of X H leading to an approximation of X H with the optimal rate n ?H/N (log?n)1/2. 相似文献