Calibration optics

Carbon - The aerosol collected on the Tissuequartz filters was analyzed for total carbon by the nondestructive technique of proton-induced gamma-ray emissions (17) and graphitic carbon (soot) by calibrated optical reflectance at Washington University, St. Louis, Missouri. The estimated error in measurement of total carbon per filter was 5 yg or 20%, whichever was greater. The estimated error for soot was lyg or 20%, whichever was greater. 

The Babinet compensator is a calibrated optical device comprising two wedge-shaped pieces of quartz arranged so that their optic axes, and the light path, are... 

Self-calibrated Optical Combs Absolute Optical Frequencies... 

Crystal Size Measurement. The size distribution of the sieve crystals used also was measured in some auxiliary experiments. This was done by first suspending the sieve sample (crystal powder or crushed pellets) in a sodium hydroxide solution (to help disperse the easily-formed crystal agglomerates) and then examining the solution with a calibrated optical microscope at a magnification of 5000. About 250 particles picked at random on a slide were measured for each sample. The particles, which have a shape somewhere between that of a sphere and a cube, were treated as cubes with the length of a side equal to 2a microns. 

In recent years great advance has been made in instrumentation for ORD and, in particular, for CD measurements [see, for example, Refs. (32—39,17)]. The improvements in measurement of CD within an absorption band enabled progress in the determination of the optical activity of conjugated protein molecules, particularly for systems of relatively small activity. A frequently used calibration substance for CD instruments is (+)-camphor-10-sulfonic acid in aqueous solution. In order to achieve correct calibration, optical rotation values of the calibration substance should be transformed to CD values used for standardization (40, 41). 

FIGURE 4-11 Results of calibrating optic fiber probe in liquid-solid fluidized bed (voidage between 0.6 to 0.9) (Qin and Lin, 1982). 

Sharp Particle Blasting Calibration - Optical Flaw Characterization on Corundum... 

The dye chosen may interact with elements of the system with a consequential change in its properties. Thus the pKa of a pH indicator in solution may not necessarily have the same value when the indicator is bound to cellular or other constituents (see, for example, (20, 21)) indeed the spectra of the bound dye may differ from those of the free dye, making any simple evaluation of pH problematical. It may be that the dye is useful as a qualitative indicator of the parameter under investigation but cannot be calibrated because it forms complexes with agents required in the calibration protocol It is always good practice to use several, independent calibration procedures to check for internal consistency of the dye response. Thus when calibrating optical probes of membrane potential (22, 23) the same values should be obtained when valinomydn/ K or uncoupler carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP)/ are introduced. 

Skillful use of PLM, compensators, and calibrated optics (for measurement) are sufficient to determine the key optical features of a fiber, such as its dimensions, morphology, Rl, birefringence, and sign of elongation, without resorting to multiple mountings and repetitive experiments. 

All alloys in the system were single phase and had hep structure at room temperature. The solidus temperature for each alloy was determined in vacuum using a calibrated optical pyrometer focused on a 1 mm hole drilled to a depth of 3-4 mm in an attempt to achieve black body conditions (normally a 10 1 ratio of depth to diameter is required for black body conditions). 

Dow Chemicals has a 105,000 tpa polycarbonate plant at Stade, Germany, and an 80,000 tpa plant at Freeport, Texas. Dow recently increased polycarbonate capacity at Stade and opened a 60,000 tpa of additional capacity at Stade for Calibre optical media grades in 2001. Dow also has a... 

Heidenreich, S., Friehmelt, R., Btittner, H., Ebert, F., Methods to Calibrate Optical Particle Counters, in Preprints of Partec 98, 7 European Symp. Part Charact, Nurnberg, 1998, pp.723-732. 

The emissivity of a material relates to how intensely radiative heat is reflected from its surface. Values range between 0 and 1 from a light, reflective to an increasingly dark, dull surface. Measurement is by a duel wavelength, calibrated optical pyrometer when an object is heated to a known temperature. No standard methods for refractories currently exist despite the influence of this property in many applications. 

After this calibration step (the effective absorption coefficient is determined from a known wall thickness change and the corresponding variation of the optical film density) the evaluation of local wall thickness changes Aw (corresponding to De,o) from the nominal wall thickness w o , (corresponding to Dnom) can be done according to ... 

Measure Wall Thickness This window is used for the dialog to calibrate the algorithm aceording formula (3) and for point wise measurements after calibration. The row Ideal indicates the nominal wall thickness used, IQI indicates the wall thickness values used for calibration and the detected optical density. Local can be used for noise reduction and compensation of geometric effects. 

Profile Plot This window display the data (grey values, optical densities or wall thickness changes in mm after calibration) along the line shown in the image window. 

Fig. 5 Erosion pit inside a reducing pipe fitting, projection technique at 160 kV, profile plot with optical densities of the digitised film. The varying background caused by the geometrical set-up prevents a wall thickness calibration as in fig. 4...

The highest purity (>99.99%) oxygen is obtained through further refinement. At 99.99% the impurities total only 100 ppm. This grade of oxygen is used in the manufacture of electronic components, fiber optics (qv), etc, or for gas chromatograph calibration or research appHcations. 

The optimal conditions for accelerating of investigated reaction by ions Fe(III) and Ag(I) ai e the following pH 5,0 (acetic buffer), Cj. . =l,6T0 M, CpMSA=4T0 M, Cpp =2-10 M. Under these conditions, factors of sensitivity for kinetic determination of metals mentioned above were established as a slope s tangent of the calibration curves that is a plot of reaction velocity (change of optical density of ferroin s solution for 4 minutes) versus analyte s concentration. Factors of sensitivity for determination of Mn(II), Fe(III), Ag(I), Pd(II), Co(II) ai-e 5,5-10" 1,1-10" 2,5-10" 2,0-10" 8,0-10", respectively. 

The worked out soi ption-photometric method of NIS determination calls preliminary sorption concentration of NIS microamounts from aqueous solutions on silica L5/40. The concentrate obtained is put in a solution with precise concentration of bromthymol-blue (BTB) anionic dye and BaCl, excess. As a result the ionic associate 1 1 is formed and is kept comparatively strongly on a surface. The BTB excess remains in an aqueous phase and it is easy to determinate it photometrically. The linear dependence of optical density of BTB solutions after soi ption on NIS concentration in an interval ITO - 2,5T0 M is observed. The indirect way of the given method is caused by the fact the calibration plot does not come from a zero point of coordinates, and NIS zero concentration corresponds to initial BTB concentration in a solution. 

PSS-SG composite film was tested for sorption of heme proteins hemoglobin (Hb) and myoglobin (Mb). The peroxidaze activity of adsorbed proteins were studied and evaluated by optical and voltammetric methods. Mb-PSS-SG film on PG electrode was shown to be perspective for detection of dissolved oxygen and hydrogen peroxide by voltammetry with linear calibration in the range 2-30 p.M, and detection limit -1.5 p.M. Obtained composite films can be modified by different types of biological active compounds which is important for the development of sensitive elements of biosensors. 

In Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), a gaseous, solid (as fine particles), or liquid (as an aerosol) sample is directed into the center of a gaseous plasma. The sample is vaporized, atomized, and partially ionized in the plasma. Atoms and ions are excited and emit light at characteristic wavelengths in the ultraviolet or visible region of the spectrum. The emission line intensities are proportional to the concentration of each element in the sample. A grating spectrometer is used for either simultaneous or sequential multielement analysis. The concentration of each element is determined from measured intensities via calibration with standards. 

The ellipsometer user will always get data but unfortunately may not always know when the data or the results of analysis are correct. Improper optical alignment, bad calibration constants, reflection from the back surface of partially trans-... 

For many applications, quantitative band shape analysis is difficult to apply. Bands may be numerous or may overlap, the optical transmission properties of the film or host matrix may distort features, and features may be indistinct. If one can prepare samples of known properties and collect the FTIR spectra, then it is possible to produce a calibration matrix that can be used to assist in predicting these properties in unknown samples. Statistical, chemometric techniques, such as PLS (partial least-squares) and PCR (principle components of regression), may be applied to this matrix. Chemometric methods permit much larger segments of the spectra to be comprehended in developing an analysis model than is usually the case for simple band shape analyses. 

Short- and long-term drift in the spectral output can be caused by several factors drift in the output of the infrared light source or of the electronics, aging of the beam splitter, and changes in the levels of contaminants (water, CO2, etc.) in the optical path. These problems are normally eliminated by rapid, routine calibration procedures. 

A Q-switched, frequency-quadrupled Nd—YAG laser (X, = 266 nm) and its accompanying optical components produce and focus the laser pulse onto the sample surface. The typical laser spot size in this instrument is approximately 2 pm. A He-Ne pilot laser, coaxial with the UV laser, enables the desired area to be located. A calibrated photodiode for the measurement of laser energy levels is also present... 

An ICP-OES instrument consists of a sample introduction system, a plasma torch, a plasma power supply and impedance matcher, and an optical measurement system (Figure 1). The sample must be introduced into the plasma in a form that can be effectively vaporized and atomized (small droplets of solution, small particles of solid or vapor). The plasma torch confines the plasma to a diameter of about 18 mm. Atoms and ions produced in the plasma are excited and emit light. The intensity of light emitted at wavelengths characteristic of the particular elements of interest is measured and related to the concentration of each element via calibration curves. 

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