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171.
A. Gross 《Applied Physics A: Materials Science & Processing》1998,67(6):627-635
Received: 23 March 1998/Accepted: 21 August 1998 相似文献
172.
H. Scheer E. Gross B. Nitsche E. Cmiel S. Schneider W. Schfer H.-M. Schiebel H.-R. Schulten 《Photochemistry and photobiology》1986,43(5):559-571
Abstract— The methanolic extract of the cyanobacterium (blue-green alga) Spirulina geitleri has been treated with methanolic acid to convert all chlorophyllous pigments to their methylpheophorbides. Fractionation of the latter from methylpheophorbide a by thin layer chromatography and high pressure liquid chromatography yielded methylpheophorbide-RCI. Its structure has been determined as 132S-hydroxy-20-chloro-methylpheophorbide a by 1H-nuclear magnetic resonance, absorption and circular dichroism spectroscopy, mass spectrometry and by partial synthesis from chlorophyll a. The pigment is isolated from Spirulina geitleri irrespective of the use or omission of chlorinated substances during the isolation procedure. 相似文献
173.
Benedict H. Gross 《Inventiones Mathematicae》1997,130(2):287-313
174.
175.
Maria Luiza LAPA DE Souza 《K-Theory》2002,25(3):233-249
We construct two cohomological invariants associated to pairs of Lagrangian sub-bundles of a symplectic bundle on a compact manifold upon which a compact Lie group is acting. The first invariant, which we call the classical equivariant Maslov H-invariant, provides an obstruction to Lagrangian transversality and lives in the Borel cohomology. The second invariant, which we call the equivariant Maslov U-invariant, generalises the author's results in K-Theory 13 (1998), 347–361 to the equivariant context and provides a necessary and sufficient condition for equivariant Lagrangian transversality, up to homotopic stability, and lives in the U-theory (intermediate between the real complex K-theories). As an application, we show that two Lagrangian sub-bundles of a symplectic bundle on a homogeneous space are always stably transverse. 相似文献
176.
T. D. Johnson F. Cristancho C. J. Gross M. Kabadiyski K. P. Lieb D. Rudolph M. Weiszflog T. Burkardt J. Eberth S. Skoda 《Zeitschrift für Physik A Hadrons and Nuclei》1994,347(4):285-286
Doppler shift attenuation lifetime measurements have been carried out for the 3qp and isomeric rotational bands in83Y using the reaction58Ni(28Si,3p). While the transitional quadrupole moments in the 3qp bands are slightly lower than in the 1qp bands, we found evidence for a strong reduction in ¦Qt¦ for the isomeric band. 相似文献
177.
M. K. Kabadiyski F. Cristancho C. J. Gross A. Jungclaus K. P. Lieb D. Rudolph H. Grawe J. Heese K. -H. Maier J. Eberth S. Skoda W. -T. Chou E. K. Warburton 《Zeitschrift für Physik A Hadrons and Nuclei》1992,343(2):165-177
The reaction58Ni(36Ar, 4p)90Mo has been studied at a beam energy of 149 MeV. A detector array consisting of the OSIRIS spectrometer (12 Compton-suppressed Ge detectors), four charged-particleδE detectors and seven NE-213 neutron detectors at the VICKSI accelerator in Berlin has been used to measure the gamma radiation inγγ- and particle-γγ-coincidence mode. An additional Ge detector was placed at 162? to the beam direction to provide information on DCO ratios. The level scheme of90Mo has been extended up to an excitation energy of about 12 MeV and probable spin 23?. Some 70 transitions and 40 levels have been newly identified. Spin assignments have been proposed on the basis of measured DCO ratios. Shell model calculations in a model space consisting of the proton 1f 5/2, 2p 3/2, 2p 1/2, and 1g 9/2 orbits and the neutron 2p 1/2, 1g 9/2, 1g 7/2, 2d 5/2, 2d 3/2, and 3s 1/2 orbits with some truncation were made for states above 9? and the predicted structure of these states is discussed. 相似文献
178.
We calculated the contributions of the two-particle one-hole (2p-1h) and the one-particle two-hole (1p-1h) excitations to the imaginary partW(E, R) of then-40Ca optical potential. The bound single particle states and energies of the40Ca nucleus are calculated quantum mechanically by solving the Schrödinger equation with a Woods-Saxon potential. For the excited states in the continuum we use the Thomas-Fermi approximation. Different forms of contact residual interactions have been tested. A combination of aδ-force and a smeared SDI can fit the phenomenologicalW(E, R). 相似文献
179.
W. Fieber K. Bharuth-Ram J. Heese F. Cristancho C. J. Gross K. P. Lieb S. Skoda J. Eberth 《Zeitschrift für Physik A Hadrons and Nuclei》1989,332(4):363-370
Deformation parameters of the positive parity yrast band and negative parity bands in83Zr are deduced from lifetimes andE2/M1 mixing ratios. Lifetimes of high spin states have been determined from recoil distance Doppler shift and Doppler shift attenuation measurements using the54Fe(32S,2pnγ) 83Zr reaction. Ten lifetimes and five lifetimes limits were determined. The positive parity band, built on theg 9/2 K=5/2 orbital has an average deformation ¦β 2¦=0.28(2), and shows a reduction ofE2 transition strengths in the observed backbend region at Iπ≈21/2+. In contrast, theE2 strengths in the negative parity states show a steady increase up to Iπ≈=15/2?. These states are more strongly deformed than the positive parity states (¦β 2¦=0.33(3)). TheE2/M1 mixing ratios show that the negative parity band hasK=3/2 and is prolate, and favour oblate deformation for the positive parity yrast band. In theK=1/2? band theE2 strength of the 7/2?→3/2? transition yields a deformation ¦β 2¦=0.26(5). The band structure is compared with calculations within the Hartree-Fock Bogoliubov cranking model. 相似文献
180.
BARB FLORIN DAN; KONING WILLEM DE 《IMA Journal of Mathematical Control and Information》1994,11(1):63-73
In this paper we consider the fixed finite-order digital linear-quadraticcontrol of Pritchard-Salamon infinite-dimensional systems withunbounded input and output operators under gaussian disturbances.A set of necessary conditions is given in terms of the solvabilityof a discrete-time Hyland-Bernstein system of equations (twomodified Riccati equations and two modified Lyapunov equationscoupled by an projection operator). 相似文献