Cool white fluorescence

Fig. 11. Energy distributions of CIE standard illuminant A, a tungsten incandescent lamp a cool white fluorescent lamp E and CIE standard illuminant...

Color-order systems, such as the many MunseU collections available from Macbeth, have been described previously. Essential for visual color matching is a color-matching booth. A typical one, such as the Macbeth Spectrahte, may have available a filtered 7500 K incandescent source equivalent to north-sky daylight, 2300 K incandescent illumination as horizon sunlight, a cool-white fluorescent lamp at 4150 K, and an ultraviolet lamp. By using the various illuminants, singly or in combination, the effects of metamerism and fluorescence can readily be demonstrated and measured. Every user should be checked for color vision deficiencies. 

Cultures of G. polyedra (L. polyedrum) are grown at 20 5°C in a supplemented sea water medium (Hastings and Sweeney, 1957 Hastings and Dunlap, 1986), under cool-white fluorescent lighting of a 12-hr light/12-hr dark cycle. The cultures are inoculated at densities of 100 to 500 cells/ml. After 2-4 weeks, cells are harvested by vacuum filtration on a filter paper at cell densities of 7,000-15,000 cells/ml, yielding 0.3-0.7 g wet cells per liter of culture. 

The cultures grew at 18-20°C under a constant illumination (150 pmol photons m 2-s 1) provided by cool-white fluorescence lamps. For the anaerobic induction, cells were harvested by centrifugation (5 min, 3000xg) in the exponential growth phase at an approximate culture concentration of2><106 cells ml 1 and afterwards resuspended in fresh TAP medium. 

Culture of Dinoflagellate. The isolate of toxicus (SIU 350) used in this study was obtained from the South Sound of Virgin Gorda, British Virgin Islands. The species was brought into unialgal culture and maintained in enriched sea water ( ) under continuous light (3200 lux cool white fluorescent) at 27.0° C. 

The development of large-scale cultures involved transferring cells from stock cultures to a series of two liter Fernbach flasks containing enriched seawater medium. After the early stationary phase of growth had been reached (approximately 15-20 days) each of these cultures were used to innoculate 18 liters of the same medium in 20 liter carboys. Large-scale cultures were grown under continuous light (4300 lux cool white fluorescent) at 27.0° C. 

Growth of Seedlings. Cucumber (Cucumis sativus L., cv. Wisconsin SMR-IS) and soybean (Glycine max L. Merr., cv. Wayne) were grown in vermiculite and watered daily in a controlled environment chamber (26 2 C day, 21 2 C night) on a 12 hr photoperiod (eight 30-W cool-white fluorescent tubes plus four 25-W incandescent bulbs 200+foot-candles). The balanced nutrient solution of Frick and Mohr (H9), modified to include 1 g/1 Ca(N03)2 but without sucrose, succinic acid and kinetin, was applied on alternate days. 

In the case of photostability testing the pharmaceutical ingredient may be subjected to xenon, metal halide, near UV, or cool white fluorescent lamp exposure. 

Macbeth 5000 K fluorescent, a Philips Ultralume fluorescent, and a Sylvania Cool White fluorescent tube. Some color constancy algorithms try to find out what type of illuminant produced the particular color sensation, which was measured by the sensor. If we measure the entire power spectrum for a particular patch of our object and also know the type of illuminant used, then it is easy to compute the BRDF. Let L(X) be the measured power spectrum and let E A.) be the power spectrum of the illuminant. Assuming a Lambertian surface, where the BRDF is independent of the normal vector of the patch Nobj, and also independent of the normal vector that points to the direction of the light source Ni, we... 

Figure 3.18 Power spectrum of four different illuminants a Sylvania 75 W halogen bulb, a Macbeth 5000 K fluorescent, a Philips Ultralume fluorescent, and a Sylvania Cool White fluorescent tube. The power spectra were measured by Funt et al. (1998) with a Photoresearch PR-650 spectrometer.

Figure 2 HPLC-related substance chromatograms (UV detection) of 297802 tartrate aqueous solution exposed to cool-white fluorescent light ( 17,000 lux) for 3 and 7 days.

In option 2, the same sample should be exposed to both the cool white fluorescent and the near ultraviolet lamp. 

Figure 2 Spectral irradiance of a pair of cool white fluorescent lamps (OSRAM, model L18W/20, 60-cm long, 20 W) measured at 9-cm distance.

After 2 cell generations remove the BUdr and expose the cells for 30 min to light from a 40 W Cool White fluorescent lamp (General Electric). Prototrophs are killed. 

Figure 6-3 Spectral Energy Distribution of Sunlight (S), CIE IUuminant (A), Cool White Fluorescent Lamp (B), and Sodium Light (N)...

Illuminant F2 (4230 K) refers to a cool white fluorescent (CWF) lamp. 

Figure 2.3. Spectral power distribution of cool white fluorescent lamp (IES, 1981 Billmeyer and Saltzman, 1981).

The Macbeth Division of the Kollmorgen Corporation [41] has categorized the basic three different light sources, daylight, incandescent, and cool white fluorescent, into a viewing box. Improvements in standardizing these different light sources... 

Unfiltered cool-white fluorescent light has a significant ultraviolet component that can be absorbed by the transport materials and lead to photochemical... 

The design, discussed in detail in this paper, is that of a photostability cabinet capable of carrying out accelerated studies under controlled conditions of light and heat. A new feature of this cabinet was its incorporation of the major new light source of the day, the "cool-white" fluorescent lamp. This lamp was chosen because it was used at that time in most areas where pharmaceutical raw materials, in-process and final products, were to be found. This also included storage areas, pharmacies and homes. 

Option 2 is defined as, "A cool-white fluorescent lamp as defined in ISO 10977 (1993)" and "A near ultraviolet fluorescent lamp having a spectral power distribution from 320 to 400 nm with a maximum transmission energy emission between 350 and 370 nm a significant proportion of UV should be in both bands of 320 to 360 nm and 360 to 400 nm."... 

How is one to proceed if the sample shows no change after exposure to the 200Wh/m UV dose but is decomposed after the 1.2 million lux hours in a test chamber designed according to Option 1 (e.g., xenon lamp) One possibility is to rerun the test using a filter to eliminate the UV irradiation in excess. Another possibility is to rerun the exposure to 1.2 million lux hours using a cool white fluorescent tube. If the sample is stable to this VIS exposure, it meets the ICH guideline. 

It should also be noted that the spectral power distribution for the "cool white" lamp given in ISO 10977 1993(E) is not that of "cool white" fluorescent lamp but that of a the visible "cool white" spectrum to which the mercury lines have been added (30). This lamp also has a CCT of approximately 4100 K. There is one known notable exception to this last statement and that is Luzchem Research Inc. (33), which does supply a spectrum for each lamp that they sell if it is to be used for ICH photostability testing. 

Option 2. Cool white fluorescent lamp and near-UV fluorescent lamp. 

---