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R. Signer

Bio: R. Signer is an academic researcher from University of Bern. The author has contributed to research in topics: Dew point & Freundlich equation. The author has an hindex of 9, co-authored 21 publications receiving 343 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, eine Abanderung der bekannten Verfahren zur Isolierung von Desoxyribonucleinsaure angegeben is discussed.
Abstract: Es wird eine Abanderung der bekannten Verfahren zur Isolierung von Desoxyribonucleinsaure angegeben. Die so hergestellten Praparate zeichnen sich durch hohes Molekulargewicht aus. Die Nucleinsaure wird gekennzeichnet durch Viskositat, Stromungsdoppelbrechung und Trubungsgrad verdunnter Losungen und durch die Saure- und Basenbindung.

73 citations

Journal ArticleDOI
TL;DR: In this article, a Verfahren beschrieben, das die Darstellung hochmolekularen Natrium-thymonucleinats in grosseren Mengen with guter Ausbeute gestattet.
Abstract: Es wird ein Verfahren beschrieben, das die Darstellung hochmolekularen Natrium-thymonucleinats in grosseren Mengen mit guter Ausbeute gestattet. Nach verschiedenen Methoden hergestellte Praparate werden auf Proteingehalt und Viskositaten ihrer verdunnten Losungen untersucht.

57 citations

Journal ArticleDOI
TL;DR: In this paper, the total vapor pressure and the heats of mixing of the water-tetrahydrofuran and water-diethyl ether systems were measured at 25°.
Abstract: The total vapor pressures and the heats of mixing of the water-tetrahydrofuran and water-diethyl ether systems were measured at 25°. Density, index of refraction, and KARL-FISCHER-titration were used to determine concentrations for the total pressure measurements. The partial pressures, activity coefficients, excess free energies, entropy functions, and excess volumes were calculated.

49 citations

Journal ArticleDOI
TL;DR: In this paper, a massig konzentrierten Losungen von linearen Makromolekeln zeigen eine sehr starke Abhangigkeit der Viskositat and the Doppel-brechung von der Konzentration and dem Gefalle, die durch die vorliegenden Theorien der unendlich verdunntenLosungen nicht wiedergegeben werden kann.
Abstract: Die massig konzentrierten Losungen von linearen Makromolekeln zeigen eine sehr starke Abhangigkeit der Viskositat und der Doppel-brechung von der Konzentration und dem Gefalle, die durch die vorliegenden Theorien der unendlich verdunnten Losungen nicht wiedergegeben werden kann. Die Strukturviskositat ergibt am Anfange ein lineares Absinken der Viskositat mit dem Gefalle, was ein ausgesprochener Konzentrationseffekt ist. Die sehr unubersichtlichen Verhaltnisse bei der Stromungsdoppelbrechung konnen als Orientierungseffekte der Einzelmolekel gedeutet werden, falls man als effektive Scherspannung das Produkt aus dem Gefalle und der wirksamen Viskositat η* einfuhrt. Die Werte der letzteren mussen aus den entsprechenden Viskositatsmessungen entnommen werden. Genau genommen liefern diese Messungen das Produkt [η] η*, welches allein die fur das Verhalten der gelosten Makromolekel charakteristische Funktion der Konzentration und des Gefalles darstellt. Mit dieser Vorstellung erhalt man eine befriedigende Wiedergabe der Messungen fur Losungen, deren relative Viskositat bis zu 2500 geht. Ferner hat man auf diese Weise die Moglichkeit, aus bequem auszufuhrenden Messungen bei massigen Konzentrationen die charakteristischen Konstanten der gelosten Einzelmolekel, die spezifische Maxwell'sche Konstante und die Orientierungszahl, zu bestimmen. Allerdings hat man dabei auch die Viskositaten fur die gleichen Gradienten zu messen.

26 citations

Book ChapterDOI
TL;DR: The chapter presents the basic principles of countercurrent distribution, including the distribution law of Nernst and Partition Coefficient, multiple distribution, calculation of the fundamental process, and distribution curves.
Abstract: Publisher Summary The chapter discusses the countercurrent distribution in protein chemistry. The chapter presents the basic principles of countercurrent distribution, including the distribution law of Nernst and Partition Coefficient, multiple distribution, calculation of the fundamental process, and distribution curves. The two types of distributions are— namely, batteries in which the phases are discontinuously displaced, and columns in which the phases are in continuous flow. The efficiency of a distribution column or battery is judged by its separative power and its capacity. The methods for increasing the number of transfers over the number of distribution cells consist in the withdrawal of fractions at one or both ends of the battery. These possibilities are discussed briefly. A few typical examples of the application of countercurrent distribution are discussed in this chapter. Successful application of countercurrent fractionation requires a suitable two-phase solvent system, in which both phases exert a solvent action on the components of the mixture. The solutes should neither suffer decomposition in the solvent system nor should proteins undergo denaturation in it. Countercurrent distribution has been successfully applied to the isolation of amino acids, peptides, and polypeptides. However, large-scale equipment for fractionation of amino acids is justified only when it is employed for preparative purposes.

24 citations


Cited by
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Journal ArticleDOI
TL;DR: Evidence is presented that formation of this complex (complex I) is specific for base-paired regions either in DNA, RNA or RNA: DNA hybrids, and that the basis of this specificity is intercalation of the dye between base pairs.

2,229 citations

Journal ArticleDOI
Rolf Sander1
TL;DR: According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution as discussed by the authors, and a compilation of 17 350 values of Henry's Law constants for 4632 species, collected from 689 references is available at http://wwwhenrys-law.org
Abstract: Many atmospheric chemicals occur in the gas phase as well as in liquid cloud droplets and aerosol particles Therefore, it is necessary to understand the distribution between the phases According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution Henry's law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format The compilation contains 17 350 values of Henry's law constants for 4632 species, collected from 689 references It is also available at http://wwwhenrys-laworg

1,935 citations

Journal ArticleDOI
TL;DR: A new spectrofluorometric method for determining DNA and RNA using this principle is described, specific for nucleic acids, can be used over a wide range of salt concentrations, and has a good sensitivity.

643 citations

Book ChapterDOI
Rees Da1
TL;DR: The gel state is considered characteristic of polysaccharides in the way that polypeptides and globular proteins can characteristically occur as compact particles having a high degree of internal order, or nucleic acids can occur as chain pairs in highly ordered and complementary association.
Abstract: Publisher Summary It is noted that the gel is the most typical state for polysaccharides, both in biological and artificial systems. The polymer chains usually form an interconnected network that gives rise to characteristic texture and properties. Polysaccharide gels have various biological functions essentially in the wall of the young plant-cell, in animal fluids and connective tissues, and in the bacterial capsule. They also have widespread commercial uses, particularly in foodstuffs, cosmetics, paper, and textiles. The gel state is considered characteristic of polysaccharides in the way that polypeptides and globular proteins can characteristically occur as compact particles having a high degree of internal order, or nucleic acids can occur as chain pairs in highly ordered and complementary association. Polysaccharides also make a distinctive contribution to natural-polymer chemistry in showing, in terms of molecular structure, interaction of chain molecules in three-dimensions to provide physical and biological properties of gels.

538 citations