Emissivity difference

With particles, the contaminant concentration in the duct is determined by isokinetic sampling with subsequent laboratory analysis use of a calibrated direct reading instrument. If the concentration distribution in the duct is uneven, a complete survey of the concentration distribution with the corresponding duct velocities and cross-sectional area is required. National and ISO standards provide information on isokinetic sampling and velocity measurements. In the case of particles, the airborne emission differs from the total emission, for example in the case of granular particulate. The contaminant settling on surfaces depends on particle distribution, airflow rates, direction in the space, electrical properties of the surfaces and the material, and the amount of moisture or grease in the environment. 

El-Sayed 28> has reported on the phosphorescence spectrum of [2.2]paracyclophane. The emission differs both in wavelength ( 4700 A) and in duration (3.3 s) from that of benzene ( 3400 A, 6 s) hence a favorable intersystem crossing from the lowest singlet to the emitting triplet state was inferred. The emission spectrum also indicates that interactions take place between the two aromatic nuclei in the triplet state. 

ThermoWood is not resistant to exterior weathering and the colour will gradually change to the grey that is characteristic of outdoor exposed wood. In addition, exposure in exterior conditions results in the formation of small cracks on the surface of uncoated wood. Unpigmented or low-build stain coatings do not protect the surface of the wood, but solvent-borne alkyds and water-borne acrylic paints have been found to exhibit better performance than on unmodified wood. VOC emissions from the heat-treated wood are lower compared to unmodified wood and the compositions of the emissions differ. The level of emissions is lower when the wood is treated at a higher temperature. Emissions of terpenes are reduced to very low levels, and the VOC content is dominated by furfural, hexanal and acetic acid (treated at 180 °C), and by acetic acid (treated at 230 °C). ThermoWood passes ecotoxicity tests. 

The Au-Au distances are 3.1882(1) A and they are considered to be responsible for the emission band that appears at 460 nm at room temperature. When the anion in the carbene complex is BF4, the structure is similar although the Au-Au distances are substantially longer (3.4615(2) A). The different distance leads to a different emission band that is blue-shifted. This indicates a greater orbital interaction in the former, consistent with its shorter Au-Au distance. Nevertheless, the behavior in solution is similar for both. Thus, at room temperature in solution they lose their emissive properties but they recover them in frozen solutions at 77 K. Interestingly, the emission differs in color, depending on the solvent, ranging from orange (acetone) to blue (pyridine), which would seem to result from the self-association... 

Also, many research papers and data sources express these emissions differently as ... 

To calibrate the pixel sensitivities black body radiation is usually measured at different temperatures. Since a black body has an emissivity of 1 at every position, variations in detector pixel sensitivities are eliminated by a calibration function. As this IRT-method should be used here to quantify very small heat signals on combinatorial libraries with diverse materials, differences in emissivities have to be considered. Most materials are grey bodies with individual emissivities less than 1. Therefore, the calibration was not performed with a black body but with the library, as described before, a procedure that corrects not only for pixel sensitivity but also for emissivity differences across the library plate [5]. For additional temperature calibration, the IR-emission of the library is recorded at several temperatures in a narrow temperature window around the planned reaction temperature. By this procedure, emissivity changes, temperature dependence and individual sensitivities of the detector pixels can be calibrated in one step. After this... 

In the case of the analysis of "total formaldehyde by the perforator method, the ratio of perforator content/emission differs notably from one board type to another, even though for a given type of board, known wood species and glue, the./comparison is valid. The latter condition holds only in the case of quality control during manufacture, and not in product use. 

In the application of catalytic converters to vehicles, an extremely broad range of different converter designs are used. The reasons for this are that each vehicle has different raw emissions, different catalyst operation conditions and different - in most cases limited - space available in the vehicle underbody to accommodate the catalyst. 

Positron range A positron with energy travels a distance in tissue, losing most of its energy by interaction with atomic electrons and then is annihilated after capturing an electron (Fig. 6.1). Thus, the site of (3+ emission differs from the site of annihilation as shown in Fig. 6.1. The distance (range) traveled... 

A molecule can store energy in the electronic, vibrational, rotational, and translational degrees of freedom. However, the probability that energy can accumulate in these degrees of freedom and can appear in the form of chemical laser emission differs considerably. Fig. 1 shows the usual form of the reaction profile for an exothermic reaction. It is apparent that a product molecule which has just been released from the activated complex is at some distance from its equilibrium state. It contains excess energy which can in principle be given off in two ways, namely by radiative or collisional processes. There is always competition between these two types of processes. The luminescence quantum yield r]a (4) will be different, depending on the type of excitation. 

In the EC the passenger car fleet has been divided into three engine cylinder volume classes below 1.4 liter (1), between 1.4 and 21 and above 21. The year in which the new emissions standard has to be met and the level of the emission differ for each class. 

No effect of the addition of a-CD on the absorption or the emission of an aqueous solution of 15 was found [121], while the addition of p-CD caused a slight variation of the absorption [121-123], which allowed an equilibrium constant for the 1 1 complex, formation to be calculated. The fluorescence emission was monomeric and its yield was scarcely affected by the presence of the CD. The fluorescence decay was practically monoexponential with a lifetime of 72 ns. The addition of [y-CD] = 5 x 10 M to [15] = 2.5 X 10 M caused strong variations in the absorption spectrum, the appearance of a new, excimeric emission concomitant with the decrease of the monomer fluorescence. The lifetimes of the two fluorescences were 60 ns, excimeric, and 50 ns, monomeric. The fluorescence excitation spectrum of the two emissions differed and that of the monomer was very similar to that of 15 in pure water. The plots of the excimer emission increase and of the absorbance decrease with [y-CD] are sigmoids. They were fitted by the sequential formation of complexes with stoichiometry 1 1 [Ki = 1 ), 1. 2 (A2 = 10 M ), and 2 2 (A3 = 2 x 10 M ), as calculated by a computer simulation of the variations [121]. 

These CO2 emissions differ significantly from one geographical region to another. 

Depending on the type of measurement (absorption or emission), different types of cells and samples have been employed. A slightly modified working fuel cell using an ion exchange polymer membrane as solid electrolyte coated with various catalyst layers has been described [573] that enables investigations of the platinum and ruthenium atoms incorporated in the catalyst layers. In order to avoid convolution of signals of both electrode layers (which are penetrated by the X-ray beam), one catalyst layer (the cathode) was removed (cut out) in the area of the beam path. 

As shown on Fig.3, the 685 nm and 730 nm emission intensities exhibit markedly different concentration dependences which signifies that the processes responsible for the two emissions differ fundamentally. In the presence of absorption by the sample the intensity observed at the detector is expected to be linear in concentration in the low concentration regime. This applies only for our 685 nm data, while the 730 nm intensity, exhibits a quadratic concentration... 

In XRF, characteristic X-rays from an X-ray source are used to excite characteristic X-rays from a sample. X-ray emission differs in that particles such as electrons and alpha particles are the sources used to generate characteristic X-rays from a sample. Several types of X-ray emission systems will be described. 

In summary, the origins of photoluminescence mainly stem from the matrix-, native-, and doping-induced defects. Based on the experimental characterization, the first-principles calculation gives an acceptable model to explain the luminescence mechanism. For intrinsic emission, different DFT methods are applied to modify the band gap to meet the experimental value. The intrinsic Imninescence... 

Diesel engine emissions differ from those of gasoline because of significant differences in chemical properties of their respective fuels from which they are derived and the operation of the engines. Table 1 lists a comparison of the two fuels and engine operations. 

Nonanihropogenic emissions differ from "background" or "remote" From Nriagu (1989). levels. 

Current anthropogenic Pb emissions differ with the source producing the emissions, the environmental compartments receiving various source emissions, the relative mobility of lead in and out of environmental compartments, and the relative propensity for providing human exposures within the receiving compartments. Two of the principal receiving compartments are the atmosphere and soils. 

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