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Chemiluminescence apparatus

Carbon-14 content is measured by specially designed gas proportional counters (7. Aerosol samples are first converted to CO2 by combustion in a macroscale version of the thermal evolution technique. A clam shell oven was used to heat the sample for sequential evolution of organic and elemental carbon under equivalent conditions. Due to the possibility of thermal gradients, conditions in the macroscale apparatus were adjusted to produce the same recoveries of total carbon (yg C per cm of filter area) as for the microscale apparatus. Carbon-14 data are reported as % contemporary carbon based on the 1978 1 C02 content in the atmosphere. Aldehyde data referred to in this paper were obtained by impinger sampling in dinitrophenylhydrazine/acetonitrile solution and analysis of the derivatives by HPLC with UV detection (12). Olefin measurements were made by a specially designed ozone-chemiluminescence apparatus (13) difficulties in calibration accuracy and background drift with temperature limit its use to inferences of relative reactive hydrocarbon levels. [Pg.274]

Figure 1. The diagram of the multi-sample chemiluminescence apparatus. The numbers are identified in the text. Figure 1. The diagram of the multi-sample chemiluminescence apparatus. The numbers are identified in the text.
Figure 2. The diagram of the cell used in the chemiluminescence apparatus. Figure 2. The diagram of the cell used in the chemiluminescence apparatus.
All materials analyzed were ground to 40 mesh particle size, the standard amount of powder (0.1 g) was poured into the metal cuvette (1" diameter) and carefully spread to a uniform thickness. The cuvettes were placed in the separate test cells of the chemiluminescence apparatus, and covered by glass covers at room temperature under nitrogen atmosphere. Two different procedures have been utilized ... [Pg.395]

The chemiluminescence apparatus and method described provide a sensitive technique for thermal oxidative stability evaluation of materials with many important advantages ... [Pg.408]

The multi-sample chemiluminescence apparatus is low in cost and up-keep expenses, simple in operation, lightweight and flexible in use. [Pg.408]

Fig. 6-9 Schematic drawing of chemiluminescence apparatus. (Adapted from Polanyi and Woodall [43].)... Fig. 6-9 Schematic drawing of chemiluminescence apparatus. (Adapted from Polanyi and Woodall [43].)...
Figure Chemiluminescence apparatus. The second molecule is introduced through the upper sidearm. In some cases it may be necessary to produce this molecule by means of a microwave discharge through an appropriate parent molecule. Figure Chemiluminescence apparatus. The second molecule is introduced through the upper sidearm. In some cases it may be necessary to produce this molecule by means of a microwave discharge through an appropriate parent molecule.
The analysis of NO and NO2 was effected by a continuous chemiluminescence apparatus (Beckmann model 955), NH3 was detected by a continuous IR spectrophotometer (Hartmann Braun model Uras 30y N2 and N2O concentrations were measured by gaschromatographic analysis on a double packed 5A molecular sieves-Porapak Q by a Hewlett Packard instrument (model 5890) with a TCD detector. [Pg.719]

Fig. 10.47. Chemiluminescence apparatus with photodetector with resistive anode encoder, position computer and control computer [658]. (Reproduced with permission from [658] published by Elsevier Science Publishers Ltd, 1992.)... Fig. 10.47. Chemiluminescence apparatus with photodetector with resistive anode encoder, position computer and control computer [658]. (Reproduced with permission from [658] published by Elsevier Science Publishers Ltd, 1992.)...
Elemental analysis of the oils was carried out as follows carbon and hydrogen by micro combustion using a Perkin-Elmer 240 Elemental Analyzer sulphur by X-ray fluorescence using a Telsec Lab X-100 apparatus nitrogen by chemiluminescence using a Dohrmann DN-10 apparatus. [Pg.272]

Seitz, Suydam, and Hercules 186> recently developed on the basis of luminol chemiluminescence a method for chromium-III ion determination which has a detection limit of about 0.025 ppb. The method is specific for free chromium-III ions as chromium-VI compounds have no catalytic effect and other metal ions can be converted to a non-catalytic form by complexing with EDTA, since the chromium-III complex of EDTA, which is in any case not catalytically active, is formed kinetically slowly 186>. To detect extremely small light emissions, and hence very small metal concentrations, a flow system was used which allows the reactants to be mixed directly in front of a multiplier. (For a detailed description of the apparatus, see 186>). [Pg.131]

For chemiluminescence measurements, a postcolumn reactor with a pulse-dampening filter was added to the HPLC apparatus. A 3-cm piece of narrow-bore tubing joined the pulse dampener to a Valeo l-/tl T chemiluminescent reagent with the chromatographic eluent. A C8 ECONOSPHERE (250 X 4.6-mm ID) column was used. Modifications were made with the... [Pg.188]

Fig. 2. An arrested flow apparatus used for measuring the infrared chemiluminescence from reaction products with a Fourier transform spectrometer. (Reproduced from ref. 81 by permission of the authors and the American Institute of Physics.)... Fig. 2. An arrested flow apparatus used for measuring the infrared chemiluminescence from reaction products with a Fourier transform spectrometer. (Reproduced from ref. 81 by permission of the authors and the American Institute of Physics.)...
Apparatus and Method. The fixed-bed coluiiui was a 316 stainless steel tube, with an inside diameter of 1.09cm and a length of 40cm. The temperature of the column was maintained with an electric furnace located at its outer wall. Concentrations of NO and NO2 that exhausted from the bypass line and adsorption coluriui were analyzed by using a chemiluminescent NO, analyzer (Thermo Environmental Instruments Inc., model 42C). [Pg.575]

FLOW SYSTEM AND DETECTION APPARATUS FOR CHEMILUMINESCENCE STUDIES... [Pg.247]

Despite the complexity of the system, this was the first apparatus that successfully used chemiluminescent detection for the on-line monitoring of glucose with in vivo microdialysis sampling. [Pg.248]

A variant of postcapillary derivatization is chemiluminescence (CL) detection [8]. In this case, the chemical reaction replaces the light source for excitation. The detector is a PMT run at high voltage. Solutes can be tagged with CL reagents such as luminol or directly excited via the peroxyoxalate reaction. The latter works best for aminoaromatic hydrocarbons such as dansylated amines. The LCDs using CL detection approach laser levels because of the low background. However, the need for specialized apparatus has limited the applicability of CL detection. [Pg.695]

A more spectacular gaseous titration technique is used for the estimation of the concentrations of various atomic species. This involves the use of a fast flow discharge apparatus and the spectroscopic estimation of the extent of various chemiluminescent reactions. Hydrogen and nitrogen atoms may both be titrated with NO, and oxygen atoms with N02 or the reactions being... [Pg.78]


See other pages where Chemiluminescence apparatus is mentioned: [Pg.356]    [Pg.356]    [Pg.394]    [Pg.356]    [Pg.356]    [Pg.394]    [Pg.276]    [Pg.317]    [Pg.41]    [Pg.361]    [Pg.480]    [Pg.25]    [Pg.120]    [Pg.236]    [Pg.379]    [Pg.474]    [Pg.478]    [Pg.302]    [Pg.956]    [Pg.236]    [Pg.379]    [Pg.474]    [Pg.478]    [Pg.153]    [Pg.167]    [Pg.214]    [Pg.368]    [Pg.296]    [Pg.317]    [Pg.84]    [Pg.3054]    [Pg.403]    [Pg.212]   
See also in sourсe #XX -- [ Pg.388 ]




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