Determination germanium

Germanium, determination by x-ray emission spectrography, 328 enhancement by selenium, 189-191... 

Germanium solutions in the presence of phenylfluorone (1) and lauryldimethylam-monium bromide yield coloured compounds, Zmax 508 nm, el.60 x 105. This allows germanium determination at concentrations of 8-80 Xg/L. Only Sb, Sn, Cr(VI) and Mo interfere with the analysis17. Precipition and filtration of the Ge(IV)-l complex formed in... 

A. Lopez-Molinero, A. Villareal, D. Andia, C. Velilla and J. R. Castillo, Volatile germanium tetrachloride for sample introduction and germanium determination by inductively coupled plasma atomic emission spectroscopy, J. Anal. At. Spectrom., 16(7), 2001, 744 749. 

Ti values are found to be of the order of seconds in agreement with the reported value for metallic germanium determined in the static condition. Since the measurement of... 

Cetyltrimethylammonium bromide (CTA) has been found to increase greatly the sensitivity of germanium determination with phenylfluorone [5,25]. 

Analytical Scheme for Gallium and Germanium Determination in Coal... 

Analysis of refined germanium products is done in a wide variety of ways, including several methods that have become ASTM standards (47). Electronic-grade Ge02 is analyzed using an emission spectrograph to determine its spectrographic purity. Its volatile content is measured in accord with ASTM F5 and its bulk density with F6. Other ASTM standards cover the preparation of a metal biHet from a sample of the oxide (F27), and the determination of the conductivity type (F42) and resistivity (F43) of the biHet. 

The short-range order in a material is important in determining optoelectronic properties. For instance, x-ray and electron diffraction experiments performed on amorphous siHcon (i -Si) and germanium (a-Ge) have revealed that the nearest neighbor environments are approximately the same as those found in their crystalline counterparts (6) photoemission experiments performed on i -Si show that the DOS in valence and conduction bands are virtually identical to the corresponding crystal with the exception that the singularities (associated with periodicity) present in the latter are smeared out in the former. 

Analysis of zinc solutions at the purification stage before electrolysis is critical and several metals present in low concentrations are monitored carefully. Methods vary from plant to plant but are highly specific and usually capable of detecting 0.1 ppm or less. Colorimetric process-control methods are used for cobalt, antimony, and germanium, turbidimetric methods for cadmium and copper. Alternatively, cadmium, cobalt, and copper are determined polarographicaHy, arsenic and antimony by a modified Gutzeit test, and nickel with a dimethylglyoxime spot test. 

Fig. 4.10. The conductivity of uniaxially compressed (111) and (100) high purity germanium crystals leads to a determination of the shear deformation potential for the designated valley minima in the energy band (after Davison and Graham [79D01]).

Although the [100] data are quite limited, the shear deformation potential determined is the only measurement for this valley in germanium. At atmospheric pressure and small strains the (100) valley minimum is well above the (111) valley minima and not accessible for measurement. In the present... 

It should be noted that the hydride generation method may also be applied to the determination of other elements forming volatile covalent hydrides that are easily thermally dissociated. Thus, the hydride generation method has also been used for the determination of lead, bismuth, tin, and germanium. 

Malrieu predicted qualitatively that the l-silaallene framework would be nonlinear. but how much the moiety would deviate from 180 was unclear. The first quantitative values were seen with the isolation and structural determination of the two 1-silaallenes 56 and 59a, whieh have very similar Si=C=C angles of 173.5 and 172.0, respectively (Table III). This is an average deviation of 7.3 from linearity—significant, but relatively small compared to the deviations shown by the germanium and tin substituted allenes. 

Germanium is element 32. Consult Figure 8 to determine that Ge is in Group 14, row 4 of the p block ... 

With the availability of stable geometric isomers of doubly bonded germanium compounds, experimental determinations of the 7r-bond strength can be made. The enthalpy of activation for double bond isomerization in Mes(Tip)Ge=Ge(Tip)Mes (Tip = 2,4,6-triisopropylphenyl) has been determined for the Z-E conversion, 22.2 . 3 kcal/mol and for the E-Z conversion, 20.0 0.3 kcal/mol.15 These values agree well with recent theoretical estimations.7 The isomerization barrier in germaphos-... 

Multinuclear ( H, 13C, nB) NMR spectroscopy is undoubtly the most useful and powerful method for the investigation of the organoboration of 1-alkynyltin, -germanium, and -silicon compounds allowing not only the structure of the final products to be determined but also the product ratio to be ascertained (Tables 6-8). 

The HVI plates were leached with 0.1 M HC1. Be-7 was measured using intrinsic germanium coaxial and well detectors. Lead-210 was determined 30 days after collection stopped by separating and measuring Bi-210 (Poet et al., 1972). When Pb-210 was measured, the upper two HVI stages were coated with a thin layer of petroleum jelly to minimize soil particle bounce. 

X-ray diffraction (XRD) patterns for the materials were recorded on a X-ray diffractometer using nickel-filtered CuKa (0.154 nm) radiation and a liquid nitrogen-cooled germanium solid-state detector. Thermal stability of the materials was performed using a thermogravimetric analyser. The acidity of calcined samples were determined... 

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