Experiences transparency

Optical detectors can routinely measure only intensities (proportional to the square of the electric field), whether of optical pulses, CW beams or quasi-CW beams the latter signifying conditions where the pulse train has an interval between pulses which is much shorter than the response time of the detector. It is clear that experiments must be designed in such a way that pump-induced changes in the sample cause changes in the intensify of the probe pulse or beam. It may happen, for example, that the absorjDtion coefficient of the sample is affected by the pump pulse. In other words, due to the pump pulse the transparency of the sample becomes larger or smaller compared with the unperturbed sample. Let us stress that even when the optical density (OD) of the sample is large, let us say OD 1, and the pump-induced change is relatively weak, say 10 , it is the latter that carries positive infonnation. 

Conductivity detectors, commonly employed in ion chromatography, can be used to determine ionic materials at levels of parts per million (ppm) or parts per bUHon (ppb) in aqueous mobile phases. The infrared (ir) detector is one that may be used in either nonselective or selective detection. Its most common use has been as a detector in size-exclusion chromatography, although it is not limited to sec. The detector is limited to use in systems in which the mobile phase is transparent to the ir wavelength being monitored. It is possible to obtain complete spectra, much as in some gc-ir experiments, if the flow is not very high or can be stopped momentarily. 

McQueen, R.G. and J.N. Fritz (1982), Some Techniques and Results from High-Pressure Shock-Wave Experiments Utilizing the Radiation from Shocked Transparent Materials, in Shock Waves in Condensed Matter—1981 (edited by W.J. Nellis, L. Seaman, and R.A. Graham), American Institute of Physics, New York, 193-207. 

Maximum information is obtained by making Raman measurements on oriented, transparent single crystals. The essentials of the experiment are sketched in Figure 3. The crystal is aligned with the crystallographic axes parallel to a laboratory coordinate system defined by the directions of the laser beam and the scattered beam. A useful shorthand for describing the orientational relations (the Porto notation) is illustrated in Figure 3 as z(xz) y. The first symbol is the direction of the laser beam the second symbol is the polarization direction of the laser beam the third symbol is the polarization direction of the scattered beam and the fourth symbol is the direction of the scattered beam, all with respect to the laboratory coordinate system. 

Experiments were earned out to investigate the transparency of various materials produced by copolymerising 4MP1 with other olefins such as but-1-ene, hex-l-ene and oct-l-ene. 

Aqueous GPC can also be semiprepped in manner just like nonaqueous GPC. In this case one must consider carefully the buffers, salts, and biocides used in the eluant. If the fractions are destined for nuclear magnetic resonance experiments it will be imperative to either reduce the salt concentration in the eluant or remove salt after the initial fractionation. Likewise, if the collected samples are destined for infrared (IR) analysis, it is important to choose salts and buffers that have good IR transparency in the wavenumber ranges of interest. 

If paraffin permeates a white opaque paper, one can read letters through the paper because the paper becomes transparent. This phenomenon is based on the simple principle that micropores in the paper are filled with paraffin, which has a refractive index that is close to that of cellulose. If the porous PVA-PVAc composite film is soaked in organic solvents having the same refractive indices as that of PVA, the porous film is expected to become transparent again, according to the same principle as the phenomenon between paraffin and cellulose. On the basis of this consideration, subsequent experi-... 

Potassium heptafluorotantalate, K2TaF7, precipitates in the form of transparent needles. The precipitated particles must not be too fine, since fine powder usually promotes co-precipitation and adsorption of some impurities from the solution. Even niobium can be adsorbed by the surface of K2TaF7 developed during precipitation, as shown by Herak et al. [535]. On the other hand, the precipitation of large K-salt crystals should not be strived for either. Laboratory and industrial experience indicates that excessively large crystals usually contain small drops of solution trapped within the crystals. This occluded solution can remain inside of the crystal until drying and will certainly lead the hydrolysis of the material. 

It is perhaps ironic that, many years after his interest was first aroused, Stacey was to experience a fermentation failure owing to an unwanted dextran. He, and a large group of colleagues (potential co-tasters ), published a report of an attempt to make elderberry wine. A viscous, transparent gum, rather than a delicious drink, was produced. The gum was a typical, but unwelcome, dextran. 

Serizawa et al. (2002) studied experimentally, through visualization, the two-phase flow patterns in air-water two-phase flows in round tubes. The test section for air-water experiments consisted of a transparent silica or quartz capillary tube with circular cross-section positioned horizontally. The two-phase flow was realized through a mixer with different designs, as shown in Figs. 5.4 and 5.5. The air was injected into the mixer co-axially while water was introduced peripherally. 

Silicon is not as prominent a material in optoelectronics as it is in purely electronic applications, since its optical properties are limited. Yet it finds use as a photodetector with a response time in the nanosecond range and a spectral response band from 0.4 to 1.1 im, which matches the 0.905 im photoemission line of gallium arsenide. Silicon is transparent beyond 1.1 im and experiments have shown that a red light can be produced by shining an unfocused green laser beam on a specially prepared ultrathin crystal-silicon slice.CVD may prove useful in preparing such a material. 

Purpose To determine, from eight initial experiments performed under certain conditions, whether the three controlled parameters have an effect on the measurement, and which model is to be used. This factorial approach to optimization is an alternative to the use of multidimensional simplex algorithms it has the advantage of remaining transparent to the user. 

Experiments were carried out in a conical shape gas fluidized bed (0.1 m-i.d. x 0.6 m-high) that made of a transparent acryl column with an apex angle of 20°. The details of the conical fluidized beds can be found elsewhere [3]. Air velocity (Ug = 0-1.4 m/s) were measured by a flowmeter. The particle used in this study was 1.0 mm glass beads with a density of 2,500... 

The general assessment indicates that the pharmaceutical industry experiences problems with transparency of dmg registration in two out of the 10 countries— Cypms and Uganda. The main problems cited involve communication between the DRA and the industry regarding clarity of procedures and adequacy of official explanations for the rejection of an application. In Cypms, the Dmg Council also raised issues concerning the fairness of treatment of foreign versus domestic industry, and the arbitration of contradictory quality analysis results provided by different laboratories, both belonging to the Dmg Council. 

Smith, G.B., Niklasson, G.A., Svensson, J.S.E.M. and Granqvist, C.G. (1986) Noble-metal-based transparent infrared reflectors experiments and theoretical analyses forverythingoldfilms./oumolqf Applied Physics, 59, 571-581. 

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