Electrodeless

Printed circuit boards manufacture is aided by the use of KMnO. Alkaline permanganate solution is used to remove resin smeared on the interior hole wall of multilayered printed circuit boards. Additionally the hole wall is etched, resulting in a surface with excellent adhesion characteristics, for electrodeless copper (250). The alkaline permanganate etchback system containing >60 g/L KMnO and 40-80 g/L NaOH at 70—80°C, is effective for difunctional, tetrafiinctional, and polyimide resin substrates, where the level of etchback is direcdy proportional to the immersion time (10—20 min) (251). 

Elektroanalyse, /. electroanalysis, elektroaoalytisch, a. electroaualytical, Elektro-chemie, /. electrochemistry, -chemi-ker, m. electrochemist. elektrochemisch, a. electrochemical, Elektroden-abstand, m. distance between electrodes, -kohle, /. electrode carbon, elektrodenlos, a, electrodeless, without electrodes. 

Electrical units 503, 519 Electrification due to wiping 77 Electro-analysis see Electrolysis and Electrogravimetry Electrochemical series 63 Electro-deposition completeness of, 507 Electrode potentials 60 change of during titration, 360 Nernst equation of, 60 reversible, 63 standard 60, (T) 62 Electrode reactions 505 Electrodeless discharge lamps 790 Electrodes antimony, 555 auxiliary, 538, 545 bimetallic, 575... 

FIG. 12 SEM pictures of LB monolayers of particles 2 on a glass support, deposited from an aqueous solution containing disodium tetrachloropalladate (cone. 10 mol L and subsequently immersed in a plating bath for electrodeless nickel deposition for (a) 15 and (b) 40 sec. Typical SEM pictures of particle monolayers not subjected to nickel coating are shown in Figure 9. (From Ref. 156.)... 

EDL Electrodeless discharge lamp ETA AES Electrothermal atomisation atomic... 

The rapid course of the normal electrodeless titration of Fe2+ with Ce4+ also proves the occurrence of the direct "tunnelling of the electron between the ions, notwithstanding the simultaneous hydration rearrangement, viz.,... 

Strong evidence in favor of mechanism B was obtained when it was discovered that singlet oxygen produced chemically by the reaction of hydrogen peroxide and sodium hydrochlorite or from gaseous oxygen excited by an electrodeless discharge yields the same products as the direct photolysis/85-8 ... 

Additionally, advanced tools for special applications are offered, including provisions for parallel reflux, solvent extraction, and hydrolysis, as well as electrodeless discharge lamps for photochemistry (Fig. 3.10). A detailed description of these accessories can be found on the Milestone website [11],... 

UV radiation, certainly not sufficient to disrupt the bonds of common organic molecules. We therefore assume that, essentially, photoinitiation is responsible for a chemical change and MW radiation subsequently affects the course of the reaction. The objective of microwave photochemistry is frequently, but not necessarily, connected to the electrodeless discharge lamp (EDL) which generates UV radiation when placed in the MW field. 

Fig. 14.1 The electrodeless mercury lamp made by William F. Meggers. With permission from the National Institute of Standards and Technology,Technology Administration,...

The operating conditions affecting electrodeless lamp performance are a combination of many factors [30] ... 

The microwave photochemical reactor is an essential tool for experimental work in this field. Such equipment enables simultaneous irradiation of the sample with both MW and UV/VIS radiation. The idea of using an electrodeless lamp (EDL), in which the discharge is powered by the MW field, for photochemistry was bom half a century ago [46, 68]. The lamp was originally proposed as a source of UV radiation only,... 

Fig. 14.4 Apparatus for electrodeless photochemical irradiation. A. antenna, B. transmitter, C-j. capacitor, C2. variable capacitor,...

A microwave-assisted, high-temperature, and high-pressure UV digestion reactor has been developed by Florian and Knapp [44] for analytical purposes. The apparatus consists of the immersed electrodeless discharge lamp operating as a result of the MW field in the oven cavity (Fig. 14.8). An antenna fixed to the top of EDL enhanced the EDL excitation efficiency. Another interesting MW-UV reactor has... 

Simultaneous application of UV and MW irradiation has found widespread use in industry. The techniques are based on the conventional UV lamps and MW-powered electrodeless lamps and MW devices [28], The following paragraphs discuss several patents and papers that describe industrial microwave photochemistry, such as treatment of waste water, sterilization, or industrial photo induced organic synthesis. 

Ideally, the emission line used should have a half-width less than that of the corresponding absorption line otherwise equation (8.4) will be invalidated. The most suitable and widely used source which fulfils this requirement is the hollow-cathode lamp, although interest has also been shown in microwave-excited electrodeless discharge tubes. Both sources produce emission lines whose halfwidths are considerably less than absorption lines observed in flames because Doppler broadening in the former is less and there is negligible collisional broadening. 

In the method described by Willie et al. [167] atomic absorption measurements were made with a Perkin-Elmer 5000 spectrometer fitted with a Model HGA 500 graphite furnace and Zeeman effect background correction system. Peak absorbance signals were recorded with a Perkin-Elmer PRS-10 printer-sequencer. A selenium electrodeless lamp (Perkin-Elmer Corp.) operated at 6W was used as the source. Absorption was measured at the 196.0nm line. The spectral band-pass was 0.7nm. Standard Perkin-Elmer pyrolytic graphite-coated tubes were used in all studies. 

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