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101.
102.
Christian Huber Christian Krause Tobias Werner Otto S. Wolfbeis 《Mikrochimica acta》2003,142(4):245-253
This article describes the preparation and performance of an optical sensor for continuous measurement of chloride at extracellular (serum) levels (20–200mM). The sensor is based on dynamic quenching of the fluorescence of lucigenin which was photo-immobilized on a hydrogel. Quenching occurs via a collisional mechanism, and the decrease in fluorescence intensity on exposure to 100mM chloride typically is –60%. It allows the determination of chloride in the 1 to 200mM concentration range, with a precision of ±3mM at 120mM. Bromide, iodide and salicylate act as interferents, while the effect of pH and oxygen is negligibly small. The sensor displays strong fluorescence intensity, excellent reproducibility, long-term stability, response times in the order of 2–5min, and is used in a commercial serum and blood chloride analyzer.Received January 21, 2003; accepted April 6, 2003
Published online July 28, 2003 相似文献
103.
Henri Brunner Christian Zettler Manfred Zabel 《Monatshefte für Chemie / Chemical Monthly》2003,134(9):1253-1269
Summary. The synthesis of new chiral tridentate ligands is reported which coordinate transition metals in a meridional way. The ligands contain a pyridine ring, an oxazoline ring, and a strongly coordinating diphenylphosphanyl group. The methionine-derived ligand forms a copper complex, which has been studied by X-ray crystallography. The new ligands were tested in models of enantioselective catalyses, such as hydrogenation of ketopantolactone, hydrosilylation of acetophenone, and transfer hydrogenation of acetophenone.X-ray structure analysesReceived March 4, 2003; accepted March 4, 2003
Published online August 18, 2003 相似文献
104.
Jean Bricmont Joel L. Lebowitz Christian Maes 《Journal of statistical physics》1987,48(5-6):1249-1268
We derive a number of new results for correlated nearest neighbor site percolation onZ
d. We show in particular that in three dimensions the strongly correlated massless harmonic crystal, i.e., the Gaussian random field with mean zero and covariance –, has a nontrivial percolation behavior: sites on whichS
x
h percolate if and only ifh
c
. with0
c
< . This provides the first rigorous example of a percolation transition in a system with infinite susceptibility. 相似文献
105.
106.
Christian Buchta 《Monatshefte für Mathematik》1986,102(2):91-102
Denoty byp
d+i
(B
d
,d+m) the probability that the convex hull ofd+m points chosen independently and uniformly from ad-dimensional ballB
d
possessesd+i(i=1,...,m) vertices. We prove Mile's conjecture that, given any integerm, p
d+m
(B
d
,d+m)»1 asd». This is obvious form=1 and was shown by Kingman form=2 and by Miles form=3. Further, a related result by Miles is generalized, and several consequences are deduced.Dedicated to Professor E. Halwaka on the occasion of his seventieth 相似文献
107.
The diamagnetic square planar d(8) complexes [meso-arylcorrolato]copper(III) become paramagnetic upon warming, indicative of the equilibrium between the [corrolato]copper(III) and the [corrolato](+)* copper(II) forms of the complex. [meso-Triphenylcorrolato]copper(III) was structurally characterized and found to be saddled. 相似文献
108.
Christian Bellec Marie-Claude Bellassoued-Fargeau Bernadette Graffe Marie-Claude Sacquet Pierre Maitte 《Journal of heterocyclic chemistry》1990,27(3):551-555
The chemical reduction of 5H-[1]benzopyranno[4,3-d]pyrimidines with lithium aluminum hydrrde leads to 3,4-dihydro derivations. The electro-chemical reducation in acidic medium shows two monoelectronic cathodic waves. In netural or basic medium, substituted compounds in 2 position show a single bielectronic wave while two bielectronic waves are observed for unsubstituted compounds In all cases, preparative electrolysis lead to a hydrodimer in the 4,4′-positiom. 相似文献
109.
S. Suarez A. R. Goñi W. Meckbach P. R. Focke 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,6(1):55-59
Using a coaxial cylindric electron spectrometer and an electrostatic ion energy analyzer in tandem, a direct measurement of the difference of the energy of convoy peak electron and the electron equivalent ion energy of protons emerging from the downstream surface of C, Au and Al foils is performed in the proton energy range from 60 to 250 keV. This measurement is made possible using the accepted evidence that for a gas target these energies are equal. It is found that also for the beam foil convoy peak electrons, within an experimental average uncertainty of about ±0.1 eV, there is no difference between these energies. If one accepts that the origin of convoy electrons is from inside the solid, the conclusion is that no retardation by the solid surface potential barrier, which is of the order of a few eV, is observed. This is attributed to the strong electron-ion Coulomb interaction which almost completely overshadows the force exerted on the electron by the field of the surface barrier. 相似文献
110.
Demetrio De Calle García M. Reichenbächer Klaus Danzer Christian Hurlbeck Christine Bartzsch Karl-Heinz Feller 《Analytical and bioanalytical chemistry》1998,360(7-8):784-787
The extraction of wine aroma compounds was studied by direct-SPME (DI/SPME), headspace-SPME (HS/SPME) and multiple-headspace-extraction-SPME
(MHE/SPME). The aromagrams obtained by HS/SPME-CGC were evaluated with chemometrical methods for the varietal classification
of wines.
Received: 25 July 1997 / Revised: 24 September 1997 / Accepted: 7 October 1997 相似文献