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101.
Ruey-Jen Jang-Lewis Harold Dean Victory Jr. 《Integral Equations and Operator Theory》1994,18(1):88-108
LetE be a Banach lattice having order continuous norm. Suppose, moreover,T is a nonnegative reducible operator having a compact iterate and which mapsE into itself. The purpose of this work is to extend the previous results of the authors, concerning nonnegative solvability of (kernel) operator equations on generalL
p-spaces. In particular, we provide necessary and sufficient conditions for the operator equation x=T
x+y to possess a nonnegative solutionxE wherey is a given nonnegative and nontrivial element ofE and is any given positive parameter. 相似文献
102.
We present theS
1 Raman spectra of 1,4-DiPhenyl-1,3-Butadiene (DPB) in a series of linear alkanes (pentane, hexane, heptane, octane, decane, and dodecane). Bands assignable to both the 11
B
u
and 21
A
g
states are present, suggesting that the state we are observing in solution is a mixed state with both 11
B
u
and 21
A
g
character. The relative intensities of several bands associated with CoCo stretching motions in the 21
A
g
and 11
B
u
states change systematically through the solvent series. The relative intensity changes reflect a changing distribution ofs-trans conformers inS
1 DPB as the solvent is varied. We suggest that the distribution ofs-trans conformers inS
1 DPB controls the nature of the mixing between the 21
A
g
and 11
B
u
states and that the distribution of conformers is controlled by the solvent viscosity. Changes in the peak position and bandwidth of the phenyl C=C stretch with delay reflect vibrational relaxation processes inS
1 DPB. We observe anomolous behavior in pentane that we attribute to the effect of the solvent structure on the ability of DPB to exchange energy with pentane. 相似文献
103.
Joseph R. Lakowicz Zakir Murtaza Wayne E. Jones Jr. Kihan Kim Henryk Szmacinski 《Journal of fluorescence》1996,6(4):245-249
We report the first observation of polarized emission from a rhenium-phenanthroline complex, Re(CO)3(phen)Cl. Highly luminescent rhenium complexes are known, with quantum yields near 0.5 and lifetimes in excess of 10 s. The detection of polarized emission suggests the use of rhenium complexes as probes of the hydrodynamics of large macromolecular complexes and for use in fluorescence polarization immunoassays with gated detection. 相似文献
104.
M. B. Freiler M. C. Shih S. Kim M. Levy I. P. Herman R. Scarmozzino R. M. Osgood Jr. 《Applied Physics A: Materials Science & Processing》1996,63(2):143-151
We present a study of pattern-transfer and etch-induced damage in photon-induced cryoetching. Features with effective radii as small as 100 nm have been formed in both bulk and layered GaAs/AlGaAs materials. A measurement of the photoluminescence of etch-defined deep- submicrometer structures material suggests that this form of etching results in minimal process-induced damage. Modeling of the luminescence vs feature size for these features shows that the luminescence is limited only by carrier diffusion and non-radiative surface recombination. 相似文献
105.
J. A. E. Carrillo J. A. S. Lima A. Maia Jr. 《International Journal of Theoretical Physics》1996,35(9):2013-2018
The spectrum of massless bosonic and fermionic fluids satisfying the equation of statep=(–1) is derived using elementary statistical methods. As a limiting case, the Lorentz-invariant spectrum of the vacuum (=0,p=–) is deduced. These results are in agreement with our earlier derivation for bosons using thermodynamics and semiclassical considerations. 相似文献
106.
Samuel S. Wagstaff Jr.. 《Mathematics of Computation》1996,65(213):383-391
We show that the minimum period modulo of the Bell exponential integers is for all primes and several larger . Our proof of this result requires the prime factorization of these periods. For some primes the factoring is aided by an algebraic formula called an Aurifeuillian factorization. We explain how the coefficients of the factors in these formulas may be computed.
107.
108.
Summary A simple and quantitative method for the preparation and high performance liquid chromatography (HPLC) of N-acylated fluoroquinolones has been developed. The acylation procedure was performed with four different acid anhydrides and found to be applicable to several fluoroquinolones. The acylated derivatives were chromatographed directly on a Nucleosil C18 column without the necessity of further sample manipulation. Detector response for the N-acetyl derivatives of norfloxacin, ciprofloxacin, sarafloxacin, and temafloxacin was linear to at least 50 g/mL. The retention behavior of the N-acyl derivatives can be predicted by the length of the carbon chain of the amide. 相似文献
109.
Size-fractionated aerosol samples collected with micro-orifice impactors at Camden, NJ, a heavily industrialized urban area, and at two sites near Washington, DC, were analyzed for elemental constituents determined instrumentally from short-lived neutron activation products. A least-squares peak-fitting method was used with impactor calibration data to determine log-normal distribution parameters, i.e., mass median aerodynamic diameter (MMAD) and geometric standard deviation (g) for particles bearing S, V, Br, and I. For these elements, MMADs ranged from 0.24 to 0.65 m; 0.23 to 0.53 m; 0.22 to 0.61 m, and 0.20 to 0.48 m, respectively. 相似文献
110.
Sharon E. Navard John W. Seaman Jr. Dean M. Young 《Annals of the Institute of Statistical Mathematics》1993,45(4):603-614
Bertin and Theodorescu (1984,Statist. Probab. Lett.,2, 23–30) developed a characterization of discrete unimodality based on convexity properties of a discretization of distribution functions. We offer a new characterization of discrete unimodality based on convexity properties of a piecewise linear extension of distribution functions. This reliance on functional convexity, as in Khintchine's classic definition, leads to variance dilations and upper bounds on variance for a large class of discrete unimodal distributions. These bounds are compared to existing inequalities due to Muilwijk (1966,Sankhy, Ser. B,28, p. 183), Moors and Muilwijk (1971,Sankhy, Ser. B,33, 385–388), and Rayner (1975,Sankhy, Ser. B,37, 135–138), and are found to be generally tighter, thus illustrating the power of unimodality assumptions. 相似文献