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1.
This paper presents an algorithm and the supporting theory for solving a class of nonlinear multiple criteria optimization problems using Zionts—Wallenius type of interaction. The Zionts—Wallenius method, as extended in this paper, can be used for solving multiple criteria problems with concave objective and (implicit) value functions and convex feasible regions. Modifications of the method to handle nonconvex feasible regions and general nonlinear objective functions are also discussed.This research was supported, in part, by a Faculty Research Development Award and by a Council of 100 Research Grant from Arizona State University (Roy), and by a grant from Y. Jahnsson Foundation, Finland (Wallenius). The research was performed while the second author was a Visiting Professor at Arizona State University.  相似文献   
2.
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed.  相似文献   
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Zusammenfassung Durch Röntgenstrahlenbeugung mit Hilfe einer 190 mm Unicam-Hochtemperaturkamera wurde die thermische Ausdehnung von MnSe und MnSe2 von Zimmertemperatur bis 710° bzw. 522° C untersucht. Der thermische Ausdehnungskoeffizient wurde aus den Meßdaten nach der Methode der kleinsten Fehlerquadrate erhalten und beträgt für MnSe: =24,5·10–6°C–1 (94–450° C) und =14,3·10–6°C–1 (450–710° C). Die Ausdehnung von MnSe2 verläuft bis zum Bereich, in dem Zersetzung eintritt, linear. Die Methode der kleinsten Fehlerquadrate ergibt den Wert =20,0·10–6°C–1 (73–522° C).
High temperature X-ray studies of the thermal expansion ofMnSe andMnSe 2
The thermal expansion of MnSe and MnSe2 has been studied above room temperature up to 710° and 522° C, resp., by X-ray diffraction techniques using a 190 mm Unicam high temperature camera. The thermal expansion coefficients, , obtained from a linear least-squares analysis of the data are for MnSe: =24.5·10–6°C–1 (94–450° C) and =14.3·10–6°C–1 (450–710° C). The expansion of MnSe2 is linear up to the temperature range of decomposition. A least-squares analysis yields a value for of 20.0·10–6°C–1 (73–522° C).


Mit 2 Abbildungen

Herrn Prof.H. Nowotny gewidmet.  相似文献   
5.
Sezgintürk MK  Dinçkaya E 《Talanta》2005,65(4):998-1002
In the work described here, a biosensor was developed for the determination of sulfite in food. Malva vulgaris tissue homogenate containing sulfite oxidase enzyme was used as the biological material. M. vulgaris tissue homogenate was crosslinked with gelatin using glutaraldehyde and fixed on a pretreated Teflon membrane. Sulfite was enzymatically converted to sulfate in the presence of the dissolved oxygen, which was monitored amperometrically. Sulfite determination was carried out by standard curves, which were obtained by the measurement of consumed oxygen level related to sulfite concentration. Several operational parameters had been investigated: the amounts of plant tissue homogenate and gelatin, percentage of glutaraldehyde, optimum pH and temperature. Also, some characterization studies were done. There was linearity in the range between 0.2 and 1.8 mM at 35 °C and pH 7.5. The results of real sample analysis obtained with the biosensor agreed well with the enzymatic reference method using spectrophotometric detection.  相似文献   
6.
Both (±)-17α-hydroxytacamonine (3) and its 17β-isomer (4) were synthesized in two steps (one-pot) from aldehyde mixture 5/6 via the cyanohydrin reaction. NMR spectral characterization of isomer 3 revealed it to be unidentical with natural 17-hydroxytacamonine, whereas spectral data of isomer 4 were in agreement with those published for the natural isomer. The configuration at C-17 was confirmed by NOE difference spectroscopy.  相似文献   
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A new liquid chromatographic (LC)-chemometric approach was developed for the determination of sunset yellow (SUN) and tartrazine (TAR) in commercial preparations. This approach uses LC and chemometric calibration methods, i.e., classical least-squares (CLS), principal component regression (PCR), and partial-least squares (PLS), simultaneously. The combined LC-chemometric approaches, denoted as LC-CLS, LC-PCR, and LC-PLS, are based on photodiode array (PDA) detection at multiple wavelengths. Optimum chromatographic separation of SUN and TAR with allura red as the internal standard (IS) was obtained by using a Waters Symmetry C18 column, 5 microm, 4.6 x 250 mm, and 0.2 M acetate buffer (pH 5)-acetonitrile-methano-bidistilled water (55 + 20 + 15 + 10, v/v) as the mobile phase at a flow rate of 1.9 mL/min. The LC data sets consisting of the ratios of analyte peak areas to the IS peak area were obtained by using PDA detection at 5 wavelengths (465, 470, 475, 480, and 485 nm). LC-chemometric calibrations for SUN and TAR were separately constructed by using the relationship between the peak-area ratio and the training sets for each colorant. LC-chemometric approaches were tested for different synthetic mixtures containing SUN and TAR in the presence of the IS. These LC-chemometric calibrations were applied to a commercial preparation of the 2 colorants. The experimental results of the LC-chemometric approaches were compared with those obtained by a developed classical LC method using single-wavelength detection.  相似文献   
9.
Continuous 1-dimensional wavelet transform (WT) was applied to the quantitative analysis of a vitamin combination of thiamine hydrochloride (THI) and pyridoxine hydrochloride (PYR) with strongly overlapping signals. Absorbance data from the UV-Vis absorption spectrum of width 1150 were subjected to Gauss1 and Gauss2 WTs. Because of its flexibility, data processing, and its high signal amplitude, the continuous WT method is a powerful tool for analysis of multicomponent mixtures. By measuring the amplitude signals corresponding to the selected zero-crossing points of the transformed signal, we obtained the calibration curve. The validation of the calibration graphs was confirmed with different mixtures of THI and PYR at various concentration ratios. A brief explanation of the continuous wavelet method is given. MATLAB 6.5 software was used to perform the calculations. The results of our study were compared with those obtained by spectroscopic, chemometric, and liquid chromatographic methods, and good agreement was found.  相似文献   
10.
The synthesis of aldehyde intermediates suitable for the preparation of indole alkaloids of the tacamine ( 1 ) type is described. The four possible aldehydes 4–7 were prepared from methyl 5-ethylnicotinate ( 8 ) in a few simple steps using a base-catalyzed epimerization as the final step (Schemes 1 and 2). The key aldehyde 4 , which is an analogue of the important vincamine intermediate 3 (‘Oppolzer's aldehyde’), was finally converted into the indole alkaloid (±)-apotacamine ( 21 ).  相似文献   
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