Beryllium Detection

Browne K (1994) Asbestos-related disorders. In Parkes WR (ed) Occupational lung disorders, 3rd edn. Butterworth-Heinemann, Oxford, pp 411-504 British Thoracic and Tuberculosis Association and the Medical Research Council Pneumoconiosis Unit (1972) A survey of pleural thickening its relation to asbestos exposure and previous pleural disease. Environ Res 5 142-151 Butnor KJ, Sporn TA, Ingram P, Gunasegaram S, Pinto JF, Roggli VL (2003) Beryllium detection in human lung tissue using electron probe X-ray microanalysis. Modern Pathol 16 1171-1177... 

Radiometric ore sorting has been used successfully for some uranium ores because uranium minerals emit gamma rays which may be detected by a scintillation counter (2). In this appHcation, the distribution of uranium is such that a large fraction of the ore containing less than some specified cut-off grade can be discarded with tittle loss of uranium values. Radioactivity can also be induced in certain minerals, eg, boron and beryllium ores, by bombarding with neutrons or gamma rays. 

With modern detectors and electronics most Enei -Dispersive X-Ray Spectroscopy (EDS) systems can detect X rays from all the elements in the periodic table above beryllium, Z= 4, if present in sufficient quantity. The minimum detection limit (MDL) for elements with atomic numbers greater than Z = 11 is as low as 0.02% wt., if the peaks are isolated and the spectrum has a total of at least 2.5 X 10 counts. In practice, however, with EDS on an electron microscope, the MDL is about 0.1% wt. because of a high background count and broad peaks. Under conditions in which the peaks are severely overlapped, the MDL may be only 1—2% wt. For elements with Z < 10, the MDL is usually around 1—2% wt. under the best conditions, especially in electron-beam instruments. 

The visual limit of detection was between 30 and 50 ng per chromatogram zone for nickel and copper, a factor of ten worse for the alkaline earths. There was sometimes an impurity front in the same hRf range as beryllium. 

For the neutron porosity measurement, fast neutrons are emitted from a 7.5-curie (Ci) americium-beryllium (Am-Be) source. The quantities of hydrogen in the formation, in the form of water or oil-filled porosity as well as crystallization water in the rock if any, primarily control the rate at which the neutrons slow down to epithermal and thermal energies. Neutrons are detected in near- and far-spacing detectors, located laterally above the source. Ratio processing is used for borehole compensation. 

Therefore we should expect in the gaseous state to find molecules such as BeH2 and BeF2. These molecules have been detected. On the other hand, beryllium has the trouble boron has, only in a double dose. It has two vacant valence orbitals. As a result, BeH2 and BeF2 molecules, as such, are obtained only at extremely high temperatures (say, above 1000°K). At lower temperatures these vacant valence orbitals cause a condensation to a solid in which these orbitals can participate in bonding. We shall discuss these solids in the next chapter. 

Figure 3.1 James Chadwick used the apparatus depicted above to discover the neutron. The poionium source emits alpha (a) particles. The particles strike a sample of beryllium, resulting in the emission of a neutron (n ). The ejected neutrons hit the target material—paraffin, for instance—and eject a proton that is recorded by the detection device.

WDSs have excellent resolving power, and the peak-to-background ratio of each line is much higher than can be achieved with a crystal detector. With a suitable crystal of large lattice spacing it is possible to detect and count X-rays as soft as boron K or even beryllium K , and this type of spectrometer is widely used when... 

A poly(acrylaminophosphamic-dithiocarbamate) chelating fibre hasbeen used to preconcentratrate several trace metals in seawater by a factor of 200 [957]. The elements included beryllium, bimuth, cobalt, gallium, silver, lead, cadmium, copper, manganese, and indium. ICP-MS was used for detection. 

The benefits imparted by preconcentration to improved sensitivity are illustrated in the example of lead preconcentration on Chelex 100 resin [871,872], followed by analysis by ICP-AES. Without preconcentration the best detection bmit achievable is 60 ng/1, via direct nebubsation. When the Chelex 100 preconcentration step is included, the detection limit improves to 0.6 ng/1, i.e., 100 times better, which is a very important improvement achieved in the analysis of seawaters. Examinaton of Table 5.12 reveals that the following metals can be determined with detection limits in the 1 -10 ng/1 range beryllium (0.6 ng/1),... 

However, not all pairs of stars will meet such a cataclysmic end. The proof stems from the existence of novas. These also arise from the tempestuous love affairs between a white dwarf and a healthy star. The difference is that their love bums in a more reasonable manner, ejecting only a small portion of then-envelope at a time (roughly 10 " Mq). These ejecta are nevertheless loaded like galleons with radioactive isotopes such as beryllium-7 and sodium-22. One day it is hoped that their signature will be detected by the great INTEGRAL observatory. 

The gas is another phase which is detectable by microphonic photoacoustic method. The focused beam (at Beam Line 15A (PF)) at wavelength of 1.56 A was used for this experiment. Photoacoustic cell for gas phase measurement is shown in Fig. 9. The optical path was 10cm (x6mm O with beryllium windows (18mm d>, 0.5mm... 

Arfwedson fused the chrysoberyl three times with caustic potash in a silver crucible. Since a portion of the melt corresponding to about 18 per cent of the mineral failed to dissolve in hydrochloric acid, he reported this residue as silica. It is now known that beryllium hydroxide, when freshly precipitated, dissolves readily in hydrochloric acid, but becomes after a time almost completely insoluble in it (17). Therefore, it is probable that Arfwedson s silica was really the beryllium hydroxide. He then precipitated the alumina by adding ammonium hydroxide to the acid filtrate. To satisfy himself of the purity of his alumina, he saturated the alkaline solution with hydrochloric acid until the precipitate dissolved, and added a large excess of ammonium carbonate. Had any glucina [beryllia] or yttria existed in the matter, said Arfwedson, it would have been dissolved by this excess of carbonate of ammonia, and would have fallen when the filtered liquid was boiled till the excess of ammonia was driven off but the liquid stood this test without any precipitate appearing. Arfwedson was evidently unable to detect beryllia here because he had already filtered it off and reported it as silica. When American chemist Henry Seybert analyzed the same mineral in 1824 he found it to contain 15 to 16 per cent of beryllia (22). 

Other anionic complexes of beryllium that have been detected are (NH4)2Be(N03)4,141 (NH4)2Be(NCS)4-MeCN and (NH4)2Be(NCS)3-MeCN.142 ESCA studies on beryllium and magnesium complexes of the type [M(NCS)4]2 and [M(CNS)3L] (L = DMF, py, MeCN) are consistent with N-bonding thiocyanate anions being present.142 The structure of K[Be(NH2)3] shows the beryllium to be in a trigonal planar unit.143... 

Impairment of the immune response has also been demonstrated with beryllium in experimental animals (136). The long latency period associated with berylliosis development may in fact be a delayed immune response. This hypothesis is supported by the finding that lymphocyte cultures obtained from chronically exposed workers underwent a high degree of blast formation when challenged with beryllium sulfate (137). The authors suggest that this test may serve as a screen for detecting hypersensitive individuals. 

Jhe distribution of beryllium, boron, titanium, vanadium, chromium, cobalt, nickel, copper, zinc, gallium, germanium, tin, molybdenum, yttrium, and lanthanum in the principal coal-producing beds of the Interior Province has been studied by the U. S. Geological Survey. Data, methods of sampling, and analyses are discussed by Zubovic and others (II, 12). This chapter discusses the occurrence of 13 of these elements with respect to geological and geochemical environments of coal deposition and chemical properties of the elements. Zinc and tin are not included in this study because they were detected in only a few samples. 

Beryllium Beryllium was first detected in 1798 in the gemstones beryl and emerald (BesA SigOis) and was subsequently prepared in pure form in 1828 by the reduction of BeCl2 with potassium. It is obtained today from large commercial deposits of beryl in Brazil and southern Africa. Though beryllium compounds are extremely toxic, particularly when inhaled as dust, the metal is nevertheless useful in forming alloys. Addition of a few percent beryllium to copper or nickel results in hard, corrosion-resistant alloys that are used in airplane engines and precision instruments. 

Soil screening for metal contaminants with an x-ray fluorescence spectrophotometer is a technique used in EPA Method 6200. The method is applicable for 26 analytes listed with their detection limits in an interference-free matrix in Table 3.10. Light elements, such as lithium, sodium, aluminum, silicon, magnesium, beryllium, phosphorus, cannot be detected with XRF. 

To reach the low detection limits and eliminate the possibility of matrix interferences, choose the GFAA methods for analysis of antimony, arsenic, beryllium, cadmium, chromium, lead, selenium, silver, and thallium. 

A number of procedures for the determination of metals and biological samples call for the extraction of the metal with an organic chelating agent in order to remove interferences and concentrate the metal to enable detection of low levels. The urine or blood sample may be first subjected to wet ashing to enable extraction of the metal. Beryllium from an acid-digested blood or urine sample may be extracted by acetylacetone into methylisobutyl ketone prior to atomic absorption analysis. Virtually all of the common metals can be determined by this approach using appropriate extractants. 

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