Mercury cadmium tellurium

Fig. 10. Improvement of the infrared spectrophotometer. Infrared spectra of fully oxidized bovine heart cytochrome c oxidase cyanide derivatives measured with (A) a dispersive infrared spectrophotometer (Perkin-Elmer Model 180) and (B) a FTIR spectrometer equipped with a mercury/cadmium/tellurium detector (Perkin-Elmer Model 1800). Concentrations of the enzyme (O.VmM) and cyanide (19.4 M) were identical in both measurements.

Cyanide is also an effective infrared probe (Yoshikawa et al., 1985). A drawback of this reagent as an infrared probe is its infrared intensity, which is much weaker than that of CO. However, as given in Fig. 10, the recent development in the infrared technique has solved this problem with the introduction of a mercury/cadmium/tellurium (MCT) detector (Fig. 10) (Yoshikawa et al., 1995). The C-N stretch vibrational band is sensitive to many factors, such as the oxidation state and species of the coordinating metal, the structures of porphyrin ring substituents, and the ligand trans to the cyanide and protein structure (Yoshikawa et al., 1985). This technique can be quite effectively applied for determination of the protonation state of the cyanide bound at a metal site. Possible binding modes of cyanide to a ferric iron are shown by Structures (1), (11), and (HI). Infrared spectroscopy is the best method for identihcation of these... 

The kinetic investigations were carried out in a 1080 L cylindrical quartz-glass photoreactor in synthetic air (296 3 K and 760 10 Torr). As the description given here is limited to the instrumentation actually used in this smdy, the reader is referred to the literature for a more detailed description of this reaction chamber (Barnes et al., 1994). A White type multiple refleetion mirror system, operated at a total optical path length of (484.7 0.8) m, coupled to a Nicolet Nexus FTIR spectrometer equipped with a liquid nitrogen cooled mercury-cadmium-tellurium (MCT) detector, was used for reactant and reference monitoring. 

A technique which has proven useful for our studies is that of cylindrical internal reflectance (CIR), coupled with a Fourier transform infrared spectrometer. In this study, an IBM-85 FTIR equipped with either a DTGS (deuterated triglycine sulfate) or MCT (mercury-cadmium-tellurium) detector was used. The infrared radiation is focused by concave mirrors onto the 45° conical ends of a transmitting crystal (Figure 1). The crystal may be made of any material which is optically transparent, has a high mechanical strength and high index of refraction, and is resistant to thermal shock and chemical attack. Suitable materials include ZnS, ZnSe,... 

The Fourier transform infrared (FT-IR) spectra were recorded on a Spectrum One KY (Perkin Elmer, Inc., Waltham, MA) system coupled with a mercury-cadmium-tellurium (MCT) detector. The incident angle of the p-polarized infrared... 

A mercury-cadmium-tellurium detector used for MSP requires liquid nitrogen cooling... 

While group III-V (e.g., gallium phosphide and gallium arsenide) and group II-VI (e.g., mercury cadmium tellurium) semiconductor devices are far less common than silicon semiconductors, CVD operations for them have certain chemistries unique in semiconductor manufacturing.[4 l-[43] Halide CVD processes used in the manufacture of some III-V devices utilize arsenic trichloride and phosphoms trichloride as source chemicals.[ 2][ l... 

With modern commercial spectrometers equipped with a mercury-cadmium-tellurium detector, interferograms can be collected and stored at a high rate, typically 50 to 80 spectra per second, corresponding to a time resolution of 12 to... 

Mercury Telluride. Compounds of mercury with tellurium have gained importance as semiconductors with appHcations in infrared detection (9) and solar cells (10). The ratio of the components is varied, and other elements such as cadmium, zinc, and indium are added to modify the electronic characteristics. 

Paul W. Kruse, The Emergence of (Hgt ICdJ.)Te as a Modern Infrared Sensitive Material H.E. Hirsch, S.C. Liang, and A.G. White, Preparation of High-Purity Cadmium, Mercury, and Tellurium... 

Tellurium forms many sulfides and oxysulfides. The metal reacts with sulfides of zinc, cadmium, or mercury, forming tellurium sulfide ... 

The last category of detectors is the photovoltaic detectors. These non-thermal detectors are made of a photoconductive film that is an alloy of mercury, cadmium and tellurium (MCT) or indium/antimony (In/Sb) deposited on an inert support. These detectors are usually cooled down to liquid nitrogen temperature (77 K) in order to increase their sensitivity. 

Mercury cadmium telluride is used for recording thermal images in infrared cameras. The use of high-purity tellurium in cadmium teUuride solar cells is very promising, and some of the highest efficiencies for electric power generation have been obtained by using this material. 

Determination of copper as copper(I) thiocyanate Discussion. This is an excellent method, since most thiocyanates of other metals are soluble. Separation may thus be effected from bismuth, cadmium, arsenic, antimony, tin, iron, nickel, cobalt, manganese, and zinc. The addition of 2-3 g of tartaric acid is desirable for the prevention of hydrolysis when bismuth, antimony, or tin is present. Excessive amounts of ammonium salts or of the thiocyanate precipitant should be absent, as should also oxidising agents the solution should only be slightly acidic, since the solubility of the precipitate increases with decreasing pH. Lead, mercury, the precious metals, selenium, and tellurium interfere and contaminate the precipitate. 

The chalcogenides are binary compounds of a chalcogen (i.e., the elements of Group Ilb zinc, cadmium, mercury) with a less electropositive element, such as those of Group VIb (oxygen, sulfur, selenium, and tellurium). This section covers the sulfides, selenides, andtellurides. Oxides are reviewed above in Ch. 11. Most of the chalcogenides have useful optical characteristics and their applications are usually found in optics. 

The structural chemistry of some metal dithiocarbamates, i.e. systematics, coordination modes, crystal packing, and supramolecular self-assembly patterns of nickel, zinc, cadmium, mercury,363 organotin,364 and tellurium,365 366 complexes has been thoroughly analyzed and discussed in detail. Supramolecular self-assembly frequently occurs in non-transition heavier soft metal dithiocarbamates. Thus, lead(II),367 bismuth(III)368 zinc,369 cadmium,370 and (organo)mercury371 dithiocarbamates are associated through M- S secondary bonds, to form either dimeric supermolecules or chain-like supramolecular arrays. The arsenic(III)372 and antimony(III)373 dithiocarbamates are... 

Antimony, arsenic, bismuth, cadmium, calcium, cesium, chromium, cobalt, copper, gold, indium, iridium, iron, lead, lithium, magnesium, manganese, mercury, nickel, palladium, platinum, potassium, rhodium, rubidium, ruthenium, selenium, silver, sodium, tellurium, thallium, zinc... 

On the basis of chemical profile, Wood (38) predicted that arsenic, selenium, and tellurium will be methylated in the environment, and lead, cadmium, and zinc will not. Elemental concentration in the aquatic food chain has been reported for As (39), Hg (40), Cd (41), Pb (42), and Cu (43). The biological half-life of methylmercury in fish, for example, is one to two years (44). Pillay et al. (40) implicated heavy coal burning in the mercurial contamination of plankton and fish populations of Lake Erie. Other metals, notably cadmium, have been shown to be incorporated into the grazing grasses surrounding a coal burning source (27). Trace element contamination, therefore, can enter the food chain at various points. Disposal of solid wastes in the form of ash and slag is yet another environmental consideration (45). 

Whanger PD, Weswig PH, Schmitz JA, et al. 1976. Effects of selenium, cadmium, mercury, tellurium, arsenic, silver and cobalt on white muscle disease in lambs and effect of dietary forms of arsenic. Nutrition Reports International 14 63-72. 

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