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951.
On the derivative of a meromorphic function with maximum defect 总被引:1,自引:0,他引:1
952.
A.F.S. Penna Jagdeep Shah T.Y. Chang M.S. Burroughs R.E. Nahory M. Tamargo H.M. Cox 《Solid State Communications》1984,51(6):425-428
We report the observation of spatial variation of the bandgap energy of In0.53Ga0.47As in high quality epitaxial samples grown lattice matched to InP. Nine samples grown by three different techniques (LPE, VPE and MBE) were investigated and they all showed this apparently random spatial variation. A bandgap variation as large as 15 meV was observed over distances of the order of 1 mm, an effect corresponding to two percent of bandgap energy. 相似文献
953.
The linear Zeeman behaviour of the n = 1, 2 and 3 exciton absorptions near 20000 cm-1 in PbI2 single crystals was determined from measurements of the magnetic circular dichroism. The similarity of the g-value (+ 1.5 ± 0.5) for each of the n = 1, 2 and 3 lines supports the hydrogenic model. Any quadratic shifts of the n ? 2 levels were < 10 cm-1 in an applied magnetic field of 21 T. 相似文献
954.
955.
956.
Molecular interactions in lecithin-retinol monolayers 总被引:1,自引:0,他引:1
957.
958.
Crothers DS McSherry DM O'Rourke SF Shah MB McGrath C Gilbody HB 《Physical review letters》2002,88(5):053201
A new derivation of continuum distorted-wave theory is presented. It is generalized to magnetically quantized continuum distorted waves. The context is analytic continuation of hydrogenic-state wave functions from below to above threshold, using parabolic coordinates and quantum numbers including m the magnetic quantum number. This continuation applies to excitation, charge transfer, ionization, and double and hybrid events for both light- and heavy-particle collisions. It is applied to the calculation of double-differential cross sections for the single ionization of the hydrogen atom and for a hydrogen molecule by a proton for electrons ejected in the forward direction at a collision energy of 50 keV and 100 keV respectively. 相似文献
959.
Let K be the composite field of an imaginary quadratic field Q(ω) of conductor d and a real abelian field L of conductor f distinct from the rationals Q, where (d,f)=1. Let ZK be the ring of integers in K. Then concerning to Hasse's problem we construct new families of infinitely many fields K with the non-monogenic phenomena (1), (2) which supplement (J. Number Theory23 (1986), 347-353; Publ. Math. Fac. Sci Besançon, Theor. Nombres (1984) 25pp) and with monogenic (3). 相似文献
960.
RajnikantEmail author Vivek?K.?Gupta Dinesh Rachna?Gupta Samir?V.?Mistry Suresh?M.?Desai S.?S.?Madhava?Rao Amrish?C.?Shah 《Journal of chemical crystallography》2004,34(11):735-741
Claisen rearrangement of ethyl-2,4-diallyloxy--carbethoxycinnamate (1) in refluxing DMA afforded ethyl-9-allyl-2-methyl-2,3-dihydrofuro(2,3-h)benzopyran-5H-one-6-carboxylate (2) in a single step. Dehydrogenation with Pd/C (10%) in DPE furnished an unexpected isomeric compound, 9-(1,2-propenyl)-6-carbethoxy-2-methyl-2,3-dihydrofuro[2,3-h]-benzopyran-5H-one (3). This compound, C18H18O5, crystallizes in the monoclinic space group P21/n with unit cell parameters, a = 7.346(1), b = 16.482(3), c = 12.653(2),Å, and = 92.71(1)°. The structure has been solved by direct methods and refined to R = 0.056 for 1719 observed reflections. The coumarin nucleus is planar. The five-membered ring is in envelope-conformation. The crystal structure is stabilized by intra- and intermolecular CHO hydrogen bonds. 相似文献