Germanium transport

Differences in growth phase can influence metal uptake in batch-cultured bacteria. Germanium uptake by Pseudomonas putida occurs in a biphasic pattern in a catechol-enriched medium the second uptake phase corresponds to catechol degradation, products of which facilitate germanium transport into cells [35]. 

Potter, G. D., McIntyre, D. R. and Pomeroy, D. (1967). Transport of fallout radionuclides in the grass-to-milk food chain studied with a germanium lithium-drifted detector, page 597 in Symposium on Radioecology, USAEC Report No. CONF-670503, Nelson, D. J. and Evans, F. C., Eds. (National Technical Information Service, Springfield, Virginia). 

Gel2 is also of considerable importance in the transport and purification of germanium. 

Some examples of intrinsic semiconductors are silicon and germanium. These materials do not contain any impurities. The conduction mechanism can be represented in a simplified way by means of a projection diagram of a silicon or germanium crystal (fig. 11.4.6) By supplying energy to the material, the electrons are torn free from their atoms and positively charged electron holes (+) arise. Placing the material in an electric field will result in the transport of holes ... 

Pokrovski, G.S. and Schott, J., Experimental study of the complexation of silicon and germanium with aqueous organic species Implications for germanium and silicon transport and Ge/Si ratio in natural waters, Geochim. Cosmochim. Acta, 62, 3413, 1998. 

An unusual system involves the incorporation of a main group element, that is, germanium, within the macrocycle side chain. This is shown in Figure 17. The compounds were prepared in order to assess alkali metal cation transport. This was done but the results proved equivocal <2001JOM108>. 

Section of the Germanium Disc Transport System Courtesy of Lab Coimections Inc. 

The Swedish National Defence Research Institute (FOA), which from 1978 until 1983 was connected to the SSI, runs a system of high-volume aerosol samplers that normally detects very small amounts of radionuclides by high-resolution gamma spectrometry. The FOA also has access to army airplanes and helicopters to take air samples at different heights, to record measurements from the air, and to transport equipment and personnel to remote areas quickly to perform in situ measurements with portable germanium detectors. At the SSI, routine measurements of milk were run before the Chernobyl accident. Routine programs concerning environmental surveillance of nuclear power plants currently exist. 

Germanium based macrocycles (30a-b) have also recently been synthesized (89, 90). Receptor 30b has been shown to transport chloride ions in preference to bromide, although the degree of transport was only 20% in 35L (H20/CH2C12) (91). The expanded hosts (31) have also been synthesized and show similar effects to 30, indicating that ring size is not the only controlling factor in the anion complexation process (92). 

Greytak, A.B. Lauhon, L.J. Gudiksen, M.S. Lieber, C.M. Growth and transport properties of complementary germanium nanowire field-effect transistors. Appl. Phys. Lett. 2004, 84 (21), 4176-4179. 

In the course of their investigations on organogermanium compounds with anion transport capability, these authors noticed that aryl substituent(s) on germanium are effective in enhancing its Lewis acidity. Since the observed anion transport capability is most likely due to the hypercoordination in which the germanium atom can be involved with anions, chloride ion in particular, a suitable method of evaluation of germanium hypercoordination is needed. 

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