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921.
The author considers globally defined h Fourier integral operators(h FIO) with complex-valued phase functions. Symbolic calculusof h FIO is considered and, using a new complex Gauss transform,the composition of h pseudodifferential operators (h PDO) andh FIO is considered. For a self-adjoint h PDO A(h) and h PDOP(h) and Q(h) with compactly supported symbols, the resultsare applied to approximate the kernel of the operator
by a single, globally defined h-oscillatoryintegral. 2000 Mathematics Subject Classification 81Q20, 35S30. 相似文献
922.
Butler PA Humphreys RD Greenlees PT Herzberg RD Jenkins DG Jones GD Kankaanpää H Kettunen H Rahkila P Scholey C Uusitalo J Amzal N Bastin JE Brew PM Eskola K Gerl J Hammond NJ Hauschild K Helariutta K Hessberger FP Hürstel A Jones PM Julin R Juutinen S Keenan A Khoo TL Korten W Kuusiniemi P Le Coz Y Leino M Leppänen AP Muikku M Nieminen P Ødegård SW Page T Pakarinen J Reiter P Sletten G Theisen Ch Wollersheim HJ 《Physical review letters》2002,89(20):202501
The spectrum of prompt conversion electrons emitted by excited 254No nuclei has been measured, revealing discrete lines arising from transitions within the ground state band. A striking feature is a broad distribution that peaks near 100 keV and comprises high multiplicity electron cascades, probably originating from M1 transitions within rotational bands built on high K states. 相似文献
923.
Surfactant sponges are complex-fluid phases made up of convolutions of bilayer sheets. Although isotropic and free flowing they exhibit transient birefringence when stirred, reminiscent of the birefringence of lamellar phases. Previous attempts to understand this effect have led to confusing and often conflicting results. We have used a novel approach to designing the chemical system that gives us control over the relevant parameters needed to study microstructural and macroscopic responses of these phases to shear. We find a remarkable universal scaling behavior for both sponge and shear-induced lamellar states, which resolves a number of long-standing questions about these systems. 相似文献
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Timothy W. Butler Kirk R. Karwan James R. Sweigart 《The Journal of the Operational Research Society》1992,43(7):665-675
Strategic decision making in hospitals involves the assessment of linkages between decisions that are typically made in a hierarchical fashion. In hospitals, as in most large organizations, overall system performance is a function of how well the critical decisions are integrated. This paper focuses on the multi-level nature of the decisions and policies that typically need to be evaluated in hospital planning, highlighting that both optimization and simulation approaches may be required. An application involving a large general purpose urban hospital is used to illustrate the interdependency between the levels in the planning hierarchy. An optimization model is formulated to deal with facility layout and capacity allocation while a simulation model is proposed to capture the complexities of hospital operations. The linkages and information feedback between the models are shown to be critical in the design of a system that performs well and facilitates strategic hospital planning. 相似文献
930.
The halopentacarbonylmanganese(I) complexes, Mn(CO)5X(X = Cl, Br, I), react with PPh(CH2CH2PPh2)2(Triphos) to give two isomers of fac-Mn(CO)3(Triphos)X in which the Triphos ligand is only coordinated to the manganese atom through two of its three phosphorus atoms. The fac-Mn(CO)3(Triphos)X complexes may be considered as “monodentate ligands” in that the free phosphorus atoms readily displace CO and other groups in a variety of metal carbonyls to give a series of novel bimetallic complexes, e.g. Br(CO)3Mn(Triphos)Cr(CO)5 and I(CO)3Mn(Triphos)Mn(CO)4I. The reactions of Mn(CO)2[P(OMe)3](Triphos)Br with Cr(CO)5THF and Mn(CO)3(Triphos)X(X = Br, I) with O2 (and O3) to produce Br(CO)2[P(OMe)3]Mn(Triphos)Cr(CO)5 and fac-Mn(CO)3(Triphos=O)X, respectively, are also described. The IR-active COstretching absorptions exhibited by the new complexes are discussed. 相似文献