Volumetrische Methode zur Bestimmung der Phosphors?ure

Ohne Zusammenfassung     

Real-time queueing theory: A tutorial presentation with an admission control application

Real-time scheduling, or scheduling with respect to a deadline, is critical in many application areas such as telecommunications, control systems, and manufacturing. This paper presents a novel approach to real-time scheduling based on a queueing theory model. Using real-time queueing theory (RTQT), one can analytically determine the distribution of the lead-time profile (i.e., the time until the deadline is reached) of customers waiting for service. Emphasis is placed on the development of the equations used to determine the lead-time profile distribution. The development of the GI/G/1 case is presented and confirmed using simulation. Simulation results confirm prior research for the M/M/1 and GI/M/1 case. As a practical application, RTQT is used to implement a packet admission control algorithm for a telecommunications network. Using this algorithm, packet lateness was reduced by up to 31%. This revised version was published online in June 2006 with corrections to the Cover Date.     

Photochemistry of solid C60 with tunable infrared radiation

60 with trains of picosecond infrared (IR) pulses, tuned over the 8–15 μm range, is studied. At some specific wavelengths, white-light emission as well as ejection of ionic species from the solid is observed. The spectral characteristics of the white-light emission resemble those of a black body. The mass distribution of the ejected ionic species shows substantial amounts of C₆₀ coalescence products. Unexpectedly, all these processes only occur at wavelengths where solid C₆₀ is relatively transparent. No white-light emission nor ejection of ionic species is observed when being resonant with an IR-allowed transition of C₆₀. It is concluded that regular C₆₀ is not the chromophore for the observed processes, and that sequential absorption of single photons by a strong absorber that is dilute in the crystal takes place. Plausible chromophores are sites that are intercalated with alkali metals. Accumulation of energy at these sites leads to fullerene coalescence in the solid, ion ejection, and white-light emission, ultimately resulting in the destruction of the C₆₀ molecules. Received: 14 April 1998/Accepted: 22 April 1998     

Eine Methode zur Bestimmung kleiner Mengen von Verunreinigungen im o-Toluidin und o-Nitrotoluol

Ohne Zusammenfassung     

Formation and removal of alkylthiolate self-assembled monolayers on gold in aqueous solutions

We report the development of novel reagents and approaches for generating recyclable biosensors. The use of aqueous media for the formation of protein binding alkylthiolate monolayers on Au surfaces results in accelerated alkylthiolate monolayer formation and improvement in monolayer integrity as visualized by fluorescence microscopy and CV techniques. We have also developed an electrocleaning protocol that is compatible with microfluidics devices, and this technique serves as an on-chip method for cleaning Au substrates both before and after monolayer formation. The techniques for the formation and dissociation of biotinylated SAMs from aqueous solvents reported here may be applied towards the development of Au-based sensor devices and microfluidics chips in the future. A potential use of these devices includes the specific capture and triggered release of target cells, proteins, or small molecules from liquid samples.     

The temperature dependence of the volume retardation of polyvinyl acetate

Summary The volume retardation of polyvinyl acetate has been measured in the glass transition range. All experiments started from the same equilibrium conformation at a temperature above the glass transition temperatureT _g , with subsequent quenching to various temperatures near or belowT _g .The volume retardation measured as a function of time at the various temperatures was reduced to a relative volume scale. Subsequently it was tried to plot the retardation curves on one reference curve by shifting along the time scale.It was found that the shift factors could be described by a WLF-type shift parameter which varies linearly with the progress of the relative volume retardation. Thus a single master curve can be constructed from which the volume retardation after quenching from a given temperature to any lower temperature can be derived.

---

Zusammenfassung Die Volumenretardation von Polyvinylazetat wurde im Glasübergangsbereich gemessen. Dabei wurde in allen Versuchen, ausgehend von der gleichen Gleichgewichtskonformation bei einer Temperatur oberhalb der GlasübergangstemperaturT _g , schnell bis auf verschiedene Temperaturen in der Nähe von oder niedriger alsT _g abgekühlt. Die bei verschiedenen Temperaturen in Abhängigkeit von der Zeit gemessene Volumenretardation wurde auf einen relativen Volumenmaßstab übertragen. Darauf wurde versucht, die Retardationskurven durch Verschieben entlang der Zeitachse zu einer einzigen Bezugskurve zusammenzufassen.Es wurde festgestellt, daß sich die Verschiebungsfaktoren von einem Verschiebungsparameter vom WLF-Typ beschreiben lassen, der sich mit dem Fortschritt der relativen Volumenretardation linear ändert. Man kann so eine einzige Musterkurve konstruieren, aus der sich die Volumenretardation nach einem Temperatursprung von einer gegebenen Temperatur zu einer beliebigen Temperatur ermitteln läßt.

---

---

Paper presented at the Symposium at Leende of De Nederlandse Rheologische Vereniging on 21st and 22nd May 1970.     

Zur Bestimmung des Kalis nach der Lindo-Gladding'schen Methode

Ohne Zusammenfassung     

Literatur

Ohne Zusammenfassung