Irradiation measurement

Figure 16. Surface grafting of polypropylene film strips after 10 sec. irradiation measured as light absorption after dipping in aqueous crystal violet solution. The presoaking solutions contain 0.2 M benzophenone (all) and 1.3 M acrylamide (1), 0.8 M (2),...

McKenzie, R. L., W. A. Matthews, and P. V. Johnston, The Relationship between Erythemal UV and Ozone, Derived from Spectral Irradiance Measurements, Geophys. Res. Lett., 18, 2269-2272 (1991). 

Radiometers for spot cure monitor the performance (irradiance), measure fhe light guide degradation, determine optimum positioning of fhe lighf guide cable, and compare the efficiency of spot curing systems. An example of a... 

The narrow bandwidth emission is shown for the Xe excimer lamp (172 + 12 nm, Figure 17). The monochromacy of the light source is a great advantage in many preparative applications [2, 3, 66] and facilitates radiant power and irradiance measurements and calculations [2, 3] in up-scaling projects. 

The irradiance measured by such an integrating device is related to the radiance of a light source by... 

Irradiation Measurements. An Epply photometer with sensors for total global irradiance, photosynthetic active radiation (PAR), and ultraviolet (UV) radiation (295-385 nm) was used to measure irradiance continuously and averaged a measurement every 0.5 h. 

In this way, the spectral irradiance measured at the Earth s surface at a normal incidence for a wavelength X is given by ... 

Figure 4. Composites of the last 4 QBO cycles (1990-1999) for (a) 30 hPa zonal wind at Singapore, (b) total ozone at Thessaloniki, Greece and (c) global irradiance at 305 nm (solid line) and erythemal irradiance (dashed line). Total ozone and irradiances measurements correspond to clear sky conditions and solar zenith angle of 63° (updated from Zerefos et al., 1998).

The 10 min sums of erythemal solar irradiances measured simultaneously during ten months at two locations in the Czech Republic were analysed. The altitude effect is about 4 to 8% per 1000 m, the radiation amplification factor is about 1.1 and both numbers vary only slightly with solar zenith angle. The statistical model relating erythemal solar irradiance with total column ozone and solar zenith angle was developed. This model and the annual cycles of the mean and variability of total column ozone are used to estimate variability of annual and daily cycles of mean erythemal solar irradiance. 

McKenzie, R.L., Matthews, W. A., and Johnston, P. V. (1991) The relationship between erythema UV and ozone, derived from spectral irradiance measurements, Geophys. Res. Lett. 18,2269-2272. 

The time series of local noon UV (290-325 nm) irradiance measurements from January 1st 1992 to December 31st 1998 are plotted in Figures 1 and 2. The main factors determining the two distributions and the differences between them are total ozone, latitude and meteorological conditions [3, 4],... 

Figure 1. Time series of UV (290-325 nm) irradiance measurements at Rome around local noon. 6. ...

Let the area of the sensor be dAj, then the irradiance measured by the sensor is given by... 

The duration of light delivery can be defined by the total optical energy required (i.e., light dose or fluence measured in J/cm2 across the endovascular surface being treated) and the optical power (i.e., irradiance, measured in mW/cm2) applied to the endovascular surface, according to the formula ... 

In typical investigations on the behavior of modified TiC>2 surfaces upon irradiation, measurements are carried out in acetonitrile containing 0.1 M UCIO4. Under these conditions, very fast electron injection into the semiconductor surface is observed. However, it has been noted that this injection process depends strongly on the lithium concentration of the contacting acetonitrile solution [10,11]. In the absence of lithium, no injection is observed. This is an important observation since this opens up the possibility of modulating the photophysical behavior of the interfacial supramolecular assembly by external manipulation of the conditions. In this section, this observation is discussed in more detail, and, in addition, the possibility to use the surface potential of the semiconductor surface as a driving force will be considered. 

Fig. 11. The thickness of PMMA observed after 0.4 MeV He and 1 MeV He irradiation. Measurements of the thickness were before (O) and after (0) development...

Fig. 17.7 Inactivation of E. coli by sunlight in a CPC photoreactor. The insert contains the UV (continuous line) and total (dashed line) solar irradiation measured during the period of the experiment. 25th (a) and 26th (b) September 2003, in Lausanne, Switzerland. Dark control for samples that corresponds to 0, 1, 2, and 3h of the illumination exposure. Conditions VT0T = 35 L, recirculation rate = 20.5 L min-1, illumination time = 3 h (a) and 5 h (b), natural pH. Type of water LLW. The bars show the SD of four samples...

Figures 16 and 17 show percent difference between SMARTS MODTRAN results and one of many comparisons of measured and SMARTS spectral data. Agreement within the uncertainty limits of spectral irradiance measurements (1% in the visible, and 3% to 5% in the ultraviolet and infrared), is achieved.

Thermal lensing A technique that determines the alteration in the refractive index of a medium as a result of the temperature rise in the path of a laser beam absorbed by the medium. The lens produced (usually divergent) causes a change (usually a decrease) in the irradiance measured along the laser beam axis. 

D. If the net radiation balance averaged over the spine surface is due entirely to shortwave irradiation (i.e., IRabsocbed = IRemitted) and if the maximum shortwave irradiation measured perpendicular to the cylinder lateral surface is 100 W m-2, what is the mean T6 51116 to within 0.1°C Ignore spine heat conduction to the stem. 

The source to photodetector distance should always be noted as part of any illuminance or irradiance measurement, as demonstrated in Figure 13. The inverse square law states that as distance increases, the signal decreases inversely proportional to the square of the distance. This is true for a point source relationship where the source to detector distance is at least five times greater than the largest source dimension. So in effect, if the distance is halved, the signal strength per unit area is quadrupled and vice versa. Luminance and radiance measurements are independent of distance because the detection area and source intensity vary in direct proportion with distance. 

Chamber irradiation intensity mapping involves measurement of the irradiance (measured in Watts/m, near UV region, 300 00 nm) and illuminance (measured as lumen/m or Lux, VIS intensity) at different locations of the sample exposure surface... 

As shown in Figure 13, the amount of photodegradation observed in the vials was lowest in the vials placed in the center of the chamber (where the irradiance measured was the highest), and highest in the vials placed near the walls and corners of the chamber (where the irradiance measured was the lowest). These unexpected results were eventually attributable to the shading effects of the opaque caps of the vials. 

Different units are used by the ICH to measure the amount of UV and VIS photonic energy received by the sample. UV irradiance, measured using a radiometer or spectroradiometer, is expressed in W/m. After exposure at a certain irradiance level for a defined time, the total integrated energy (Wh/m ) can be calculated using the ave rage irradiance level and the time measured. 

Here Jq is the incident light irradiance (measured in units of energy per unit time per unit area), c is the light velocity, is the dimensionless efficiency fac-... 

Figure 12. Concentrations of (a) OH, (b) SO2, (c) H2SO4, and (d) nanoparticles (Dp = 2.7-4 nm) measnred at Idaho Hill, Colorado, from September 5 to 29, 1993, during periods of relatively clean (downslope) air flow. The solid curve on each plot (right axis) is the UV irradiance measured on a clear day (September 26) during the study. The vertical line at approximately 06 15 in each plot indicates sunrise. The second vertical line at approximately 07 30 in plot d indicates the beginning of measurable number concentrations of nanoparticles. From Weber et al. (1997). Used by permission of the American Geophysical Union.

Paulson, E. A., Simpson, J. J., 1977. Irradiance measurements in the upper ocean. Journal of Physical Oceanography, 7, 952-956. 

A marked change in apparent activation energy upon irradiation of silica gel is evidence that the radiation is introducing a new reaction path rather than simply more sites where it can proceed in the same way. Measured in the range from room temperature down to about —20°, the value on an irradiated sample was about 2 kcal/mole as compared with about 9 before irradiation (measured above 25°) (82). With samples not heated above —136°, a value of 0.31 kcal/mole was measured, and this rose to 0.7 upon a l-hoiu- heating to 0° in hydrogen... 

Spectral Surface Albedo From Ground Based Global and Direct UV Irradiance Measurements. J. Geophys. Res., 105,4949-4959. 

Woods, T.N., and G.J. Rottman, Solar Lyman a irradiance measurements during two... 

Woods, T.N. G.J. Rottman, S.M. Bailey, S.C. Solomon, and J. Worden, Solar extreme ultraviolet irradiance measurements during solar cycle 22. Solar Physics 177, 133, 1998. 

Figure 5.48 Generation of photovoltage from an anion exchange membrane having a viologen moiety by irradiation with a Xe lamp (load resistance 200 kQ). 1 First irradiation 2 second irradiation (measured 31 days after the first measurement 3 third irradiation (measured 2 h after the second measurement).

Figure 10.34. Illustmtion ofaging of PCfrom UV irradiation, measured bycolorimetry and DMA [STA 06]...

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