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11.
Michael D. Westmoreland Benjamin W. Schumacher Steven C. Bailey 《International Journal of Theoretical Physics》1996,35(1):62-62
Reichenbach proposed a three-valued logic to describe quantum mechanics. In his development, Reichenbach presented three different negation operators without providing any criteria for choosing among them. In this paper we develop two three-valuedderived logics for classical systems. These logics are derived in that they are based on a theory of physical measurement. In this regard they have some of the characteristics of the quantum logic developed by Birkhoff and von Neumann. The theory of measurement used in the present development is the one used previously in developingbivalent derived logics for classical systems. As these systems are derived logics, many of the ambiguities possessed by systems such as Reichenbach's are avoided. 相似文献
12.
Automatic titrators are designed to do exactly what a lab-technician used to do. Much more sophisticated automation of volumetry is possible. Omegaphoresis [3] in buffer-free [2] sample solutions automatically creates a stationary multiple component titration curve or zoned pattern with normalized concentrations of each separated species. An automatic measurement of each zone length yields their quantity. Simultaneous automatic detection of all the zones in a 10–20 component solution in less than 2 minutes, with a precision of ±2%, a required amount of the order of less than one nanomol and a resolution of ±pK < 0.01 replaces acid-base, complexometric, and certain types of redox-titrimetry. An option of the method allows identification of the components as well. 相似文献
13.
K. -H. Bergert M. Köhler und H. Schumacher 《Fresenius' Journal of Analytical Chemistry》1965,208(1):44-46
Zusammenfassung Es wird eine Methode zur sicheren Abtrennung und Bestimmung von 3,4-Benzpyren in Brotgetreide beschrieben. Die aromatischen Kohlenwasserstoffe werden nach Extraktion mit Nitromethan von gro\en Mengen wachsartiger Begleitstoffe durch Ausfrieren abgetrennt, sÄulenchromatographisch an Aluminiumoxid fraktioniert und das 3,4-Benzpyren von anderen polycyclischen aromatischen Kohlenwasserstoffen chromatographisch an teilacetyliertem Papier getrennt. Die Bestimmung des aus dem Papier extrahierten 3,4-Benzpyren erfolgt durch Aufnahme von Fluorescenzspektren fester Lösungen bei tiefen Temperaturen. Es können so noch 0,001 ppb 3,4-Benzpyren im Getreide erfa\t werden.
Die Untersuchungen sind im Auftrage des Herrn Bundesministers für ErnÄhrung, Landwirtschaft und Forsten, Bonn (Rhein), durchgeführt worden. Wir danken für die Genehmigung zur Veröffentlichung. 相似文献
Summary A method is described for the reliable separation and determination of 3,4-benzopyrene in bread cereals. After extraction with nitromethane, the aromatic hydrocarbons are separated by freezing from large quantities of wax-like accompanying substances and fractionated on aluminium oxide by column chromatography. The 3,4-benzopyrene is separated from other polycyclic aromatic hydrocarbons by chromatography on partially acetylated paper. The 3,4-benzopyrene extracted from the paper is determined by means of fluorescence spectra of solid solutions at low temperatures. Thus, quantities as small as 0.001 ppb of 3,4-benzopyrene can be determined in cereals.
Die Untersuchungen sind im Auftrage des Herrn Bundesministers für ErnÄhrung, Landwirtschaft und Forsten, Bonn (Rhein), durchgeführt worden. Wir danken für die Genehmigung zur Veröffentlichung. 相似文献
14.
Robert Schumacher 《manuscripta mathematica》1976,19(2):133-142
Cheney and others [2] have shown that, with respect to the norm of uniform convergence, the Fourier operator Fn:C2pn is the only minimal projection. For a more detailed study of operators A:C2Pn we investigate the evaluation functionals
respectively the mean of their norms
. We give a complete characterization of polynomial operators which minimize this quantity. As an application we can simplify the proof in [2]. Moreover, we show that the trigonometric interpolation operators, having the above minimal-property,are exactly those with equidistant nodes.
Diese Arbeit enthält die wesentlichen Resultate einer Diplomarbeit, die der Verfasser an der Eberhard-Karls-Universität Tübingen unter der Anleitung von A.Schönhage angefertigt hat. 相似文献
Diese Arbeit enthält die wesentlichen Resultate einer Diplomarbeit, die der Verfasser an der Eberhard-Karls-Universität Tübingen unter der Anleitung von A.Schönhage angefertigt hat. 相似文献
15.
Zhenhui Qi Dr. Changzhu Wu Dr. Paula Malo de Molina Han Sun Andrea Schulz Prof. Christian Griesinger Prof. Michael Gradzielski Prof. Rainer Haag Prof. Marion B. Ansorge‐Schumacher Prof. Christoph A. Schalley 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(31):10150-10159
A new and versatile, crown ether appended, chiral supergelator has been designed and synthesized based on the bis‐urea motif. The introduction of a stereogenic center improved its gelation ability significantly relative to its achiral analogue. This low‐molecular‐weight gelator forms supramolecular gels in a variety of organic solvents. It is sensitive to multiple chemical stimuli and the sol–gel phase transitions can be reversibly triggered by host–guest interactions. The gel can be used to trap enzymes and release them on demand by chemical stimuli. It stabilizes the microparticles in Pickering emulsions so that enzyme‐catalyzed organic reactions can take place in the polar phase inside the microparticles, the organic reactants diffusing through the biphasic interface from the surrounding organic phase. Because of the higher interface area between the organic and polar phases, enzyme activity is enhanced in comparison with simple biphasic systems. 相似文献
16.
We prove a Lifshitz tail bound on the integrated density of states of random breather Schrödinger operators. The potential is composed of translated single-site potentials. The single-site potential is an indicator function of the set tA where t is from the unit interval and A is a measurable set contained in the unit cell. The challenges of this model are that, since A is not assumed to be star-shaped, the dependence of the potential on the parameter t is not monotone. It is also non-linear and not differentiable. 相似文献
17.
In this paper,we study the surface instability of a cylindrical pore in the absence of stress. This instability is called the Rayleigh-Plateau instabilty. We consider the model developed by Spencer et ... 相似文献
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20.
Ebraheem Abdu Musad Saleh Abdullah Mohammed AL Dawsari Kakul Husain Ismail Hassan Kutty K.M.Lokanatha Rai 《Molecules (Basel, Switzerland)》2021,26(2)
A novel synthesis of thiazolo[2,3-b]quinazolines 4(a–e), pyrido[2′,3′:4,5]thiazolo[2,3-b]quinazolines {5(a–e), 6(a–e), and 7(a–e)}, pyrano[2′,3′:4,5]thiazolo[2,3-b]quinazolines 8(a–e), and benzo[4,5]thiazolo[2,3-b]quinazoloine9(a–e) derivatives starting from 2-(Bis-methylsulfanyl-methylene)-5,5-dimethyl-cyclohexane-1,3-dione 2 as efficient α,α dioxoketen dithioacetal is reported and the synthetic approaches of these types of compounds will provide an innovative molecular framework to the designing of new active heterocyclic compounds. In our study, we also present optimization of the synthetic method along with a biological evaluation of these newly synthesized compounds as antioxidants and antibacterial agents against the bacterial strains, like S. aureus, E. coli, and P. aeruginosa. Among all the evaluated compounds, it was found that some showed significant antioxidant activity at 10 μg/mL while the others exhibited better antibacterial activity at 100 μg/mL. The results of this study showed that compound 6(c) possessed remarkable antibacterial activity, whereas compound 9(c) exhibited the highest efficacy as an antioxidant. The structures of the new synthetic compounds were elucidated by elemental analysis, IR, 1H-NMR, and 13C-NMR. 相似文献