Decay time control

Statexan ITA Static control agents Static decay Static decay times Static dissipation Static drying Static electricity Static eliminating devices Static mixers Static phenomena... 

Definition and Uses of Standards. In the context of this paper, the term "standard" denotes a well-characterized material for which a physical parameter or concentration of chemical constituent has been determined with a known precision and accuracy. These standards can be used to check or determine (a) instrumental parameters such as wavelength accuracy, detection-system spectral responsivity, and stability (b) the instrument response to specific fluorescent species and (c) the accuracy of measurements made by specific Instruments or measurement procedures (assess whether the analytical measurement process is in statistical control and whether it exhibits bias). Once the luminescence instrumentation has been calibrated, it can be used to measure the luminescence characteristics of chemical systems, including corrected excitation and emission spectra, quantum yields, decay times, emission anisotropies, energy transfer, and, with appropriate standards, the concentrations of chemical constituents in complex S2unples. 

PAGE Phe Pro PSD QC Q-ToF Q-ToF-LC-MS-MS polyacrylamide gel electrophoresis phenylalanine proline post-source decay quality control quadrupole time-of-flight mass analyser quadrupole time-of-flight mass analyser in combination with (high performance) liquid chromatography and tandem mass... 

M. Sun, Fiberoptic thermometry based on photoluminescent decay times, Temperature—Its Measurement and Control in Science and Industry, Vol. 6, Part 2, pp. 715-719, American Institute of Physics, New York (1992). 

Another possible solution to the problem of analyzing multiple-layered membrane composites is a newly developed method using NMR spin-lattice relaxation measurements (Glaves 1989). In this method, which allows a wide range of pore sizes to be studied (from less than 1 nm to greater than 10 microns), the moisture content of the composite membrane is controlled so that the fine pores in the membrane film of a two-layered composite are saturated with water, but only a small quantity of adsorbed water is present in the large pores of the support. It has been found that the spin-lattice relaxation decay time of a fluid (such as water) in a pore is shorter than that for the same fluid in the bulk. From the relaxation data the pore volume distribution can be calculated. Thus, the NMR spin-lattice relaxation data of a properly prepared membrane composite sample can be used to derive the pore size distribution that conventional pore structure analysis techniques... 

The second design consideration is the dead time associated with the PWM control signals. The dead time is determined by the device turnoff time and snubber decay times. Catastrophic GTO failure would occur if both devices in one halfbridge were to conduct simultaneously. The PWM control software was modified to produce a conservative 15-/ts dead time. 

The polymer-dispersed liquid crystal was used as a modulating medium in optically controlled modulators instead of the liquid crystal [261-264], The sandwiched structure from polyimide photosensitive film and the polymer dispersed liquid crystal film - i.e. the optically controlled solid state modulator -had the characteristics presented in Fig. 36 [261]. Contrast ratio 35 1, response time > 400 ps, decay time 80 ms and sensitivity 5 x 10 sJcm 2 were obtained. 

A typical time response for a short-circuited photocurrent in the presence of hydroquinone ( Q) as an added solution redox species is shown in Figure 9. These photocurrents were stable for several hours. In the absence of in the electrolyte, the photocurrent also increased rapidly upon the onset of illumination, but subsequently decayed exponentially to 70% of its initial value in a half-decay time of ca. 25 s. This behavior is similar to that observed for chlorophyll monolayers deposited on SnC (12). Photocurrents under potentially-controlled conditions were also stable upon illumination, but exhibited slower decay characteristics when the light was turned off. This effect is unusual and is currently under further investigation. 

One respresents evolution with respect to universal time controlled by the local system Liouvillian L0, the other part describes evolution with respect to intrinsic time being the irreversible component of the process determined by the interaction Liouvillian Ly. The average <9r(t)/2r°> then corresponds to any deviation of the usual density changes due to the population or depopulation (decay) of the states. For a stationary luminescence experiment, this term therefore describes the photon fluctuations from a vibronic state of the local system H0, caused by environmental interactions. 

We applied the Langevin temperature control [57] (temperature 300 K, damping coefficient 1/ps) and the Nose-Hoover Langevin piston pressure control [58,59] (target pressure 1 atm, oscillation period 100 fs, and oscillation decay time 50 fs). To ensure stable temperature and pressure, an equilibra-... 

GABAA-R-mediated sIPSCs were examined and we found that the marked increase of decay time constant, amplitude, and area caused by this neurosteroid was not different between rats at PI9 and those in estrus. Similarly, the potentiation of sIPSCs recorded in dentate gyrus granule cells induced by the benzodiazepine lorazepam (3 /lM), although slightly reduced in rats at PI9 compared to control, resulted not different among these animals. 

Production of good phosphors requires rigorous attention to synthesis or activation conditions. Careful control of activator concentrations, usually measured in parts per million, is essential. Multiple activators may be necessary to achieve the desired color, brightness, response or decay times. Virtually umneasurable, trace amounts of unwanted substances may have such severe deleterious effects on phosphor performance that the materials are usually produced under clean room conditions rivaling those used in the production of silicon based integrated circuits. 

TTS fentanyl is not useful in acute or postoperative pain, because of the risk of respiratory depression due to the long delay and decay time, which do not allow adequate dose finding (44). Some patients have acute symptoms of morphine withdrawal, in spite of adequate pain control, when they are converted from morphine to transdermal fentanyl. The mechanism has not yet been determined (48,49). 

A field effect is also seen in the photocurrent decay time at high light intensity, interpreted in terms of bimolecular carrier recombination. Finally we discuss the rise time of a photocurrent following a rectangular light pulse. The latter results pertain to the time domain where transport is barrier controlled and bear out the importance of photo-induced barrier crossing processes. 

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