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1.
Åse Støg»rd 《Chemical physics letters》1975,36(3):357-360
Ab initio as well as semi-empirical SCF MO calculations are presented for ClCN and ONCl. The relative intensities for Cl Kβ emission in the two molecules were calculated. The calculated spectra from the ab initio wavefunctions are in excellent agreement with experiments. 相似文献
2.
The 4p photoelectron spectra of metallic Nb, Mo, Ru and Rh have been recorded. By use of a deconvolution procedure it is shown that the 4p spin-orbit component has a linewidth which significantly exceeds that of the 4p component. This suggests that N2N3N45 super Coster Kronig processes give a considerable contribution to the decay rata of the 4p hole state. 相似文献
3.
Coated piezoelectric crystal sensors for determination of trace constituents in gases are very sensitive. Detection limits down to the sub-ppb range have been reported, using injection techniques. From previous and presented data, this high sensitivity is found to be in disagreement with Sauerbrey's eqn., which allows a maximum sensitivity of about 1 ppm. By considering the adsorption of the gases on the coated surface and the calibration procedures used, the validity of Sauerbrey's eqn. is discussed. 相似文献
4.
The existence of two transitions with opposite MCD in the 38000–45000 cm?1 absorption of thiophene is demonstrated. The B-term for the lowest transition is negative, while it is positive for the higher one. Quantum mechanical calculations in the π-electron approximation resulted in energies, oscillator strengths and MCD terms in good agreement with the observed spectra. 相似文献
5.
Palladium-catalyzed oxidation of conjugated dienes in acetic acid containing CF3COOH/LiOOCCF3 results in the formation of 1-acetoxy-4-trifluoroacetoxy-2-alkenes. 相似文献
6.
BF3-mediated formation of a 2,5-oxygen bridge from carotenoids with 2-hydroxy-β-type end groups accompanied by dehydrogenation and shift of the polyene system is reported. The configuration of the Δ6,6′ double bonds are established by 1H NMR. 相似文献
7.
Sucrose is determined by its reaction in a packed-bed enzyme reactor containing co-immobilized invertase, mutarotase and glucose oxidase. The hydrogen peroxide produced is measured spectrophotometrically after a chromogenic reaction. Glucose in the samples is decomposed in a pre-reactor containing co-immobilized mutarotase, glucose oxidase and catalase. The response is linear over more than three decades. The detection limit is 0.1 μM sucrose for injection volumes of 80 μl. The sample frequency is 80 h?1 with an r.s.d. of 0.3%. The response for glucose is 0.7% that for sucrose. 相似文献
8.
The determination of fructose using a continuous analyzer based on analyte conversion in enzyme reactors followed by amperometric oxygen measurement is described. Two experimental setups were compared, allowing determinations in the ranges 0–180 and 0–25 mM fructose. In the former, fructose was continuously dialyzed versus a buffer stream conducting fructose to an enzyme reactor. This reactor contained two immobilized enzyme preparations, one with immobiized glucose isomerase (E.C. 5.3.1.5) that isomerized fructose to glucose and another that subsequently oxidized the former glucose by immobilized glucose oxidase (E.C. 1.1.3.4) with the consumption of dissolved oxygen. In the latter set-up, fructose was first isomerized in a glucose isomerase reactor, then glucose was continuously dialyzed and oxidized by glucose oxidase as above. This set-up was run in continuous operation for 1000 measurement cycles with a total decrease in response less than 15%. 相似文献
9.
Yaakov Ben Natan Yoav Benyamini H»kan Hendenmalm Yitzhak Weit 《Arkiv f?r Matematik》1996,34(2):199-224
Our main result gives necessary and sufficient conditions, in terms of Fourier transforms, for an ideal in the convolution
algebra of spherical integrable functions on the (conformal) automorphism group of the unit disk to be dense, or to have as
closure the closed ideal of functions with integral zero. This is then used to prove a generalization of Furstenberg's theorem,
which characterizes harmonic functions on the unit disk by a mean value property, and a “two circles” Morera type theorem
(earlier announced by Agranovskii).
The second author's work was partially supported by the fund for the promotion of research at the Technion-Israel Institute
of Technology. The third author's work was partially supported by the Swedish Natural Science Research Council, and by the
1992 Wallenberg Prize from the Swedish Mathematical Society. 相似文献
10.
We give a self-contained exposition of the “ensemble method”, a rule for calculating rotation averages of spectroscopic absorption intensities. The rule is mathematically exact and conceptually simple and applies to rotation averages for several axes of rotation occurring in helical and superhelical symmetry. A measure of dichroism, DI, is introduced which has a simple multiplicative property relative to axes of rotation. There are several applications to linear dichroism spectroscopy. 相似文献