Beryllium analysis

Beryllates, tetrachloro-alkali metal complexes, 3,10 Beryllium analysis, 1, 523 gravimetry, 1, 529 Beryllium, alkylalkoxy synthesis, 2, 340... 

Spectrophotometric and fluorometric reagents, once used extensively for determination of beryllium (26,27), are seldom employed. Reviews of beryllium analysis are available (15—17,24—30). 

Stokes RF and Rossman MD (1991) Blood cell proliferation response to beryllium analysis by receiver-operating characteristics. J Occup Med 33 23-28. 

Benzene-4-sulfonic acid, l-hydroxy-2-(2-hydroxy-6-suIfo-l-naphthylazo)-6-(2-hydroxy-l-naphthylazo)-metallochromic indicator, 556 Benzimidazole, 2-(o-hydroxyphenyl)-raercury determination, 532 Betrzoic acid complexes linkage isomers, 186 a-Benzoin oxime in gravimetry, 530 Benzothiazole, hydroxy-in gravimetry, 531 Benzothiazole, mercapto-in gravimetry, 534 Benzothiazole, 2-mercapto-cadmium complexes liquid-liquid extraction, 547 Benzoxazole, 2-(o-hydroxyphenyl)-cadmium determination, 531 Benzylamine, a-methyl-Al,7V-dimethyl-complexes chirality, 199 Berry pseudorotation, 39 Beryllium analysis, 523... 

Beryllium Oxalate. BeryUium oxalate trihydrate [15771 -43-4], BeC204 -3H20, is obtained by evaporating a solution of beryUium hydroxide or oxide carbonate in a slight excess of oxaHc acid. The compound is very soluble in water. Beryllium oxalate is important for the preparation of ultrapure beryllium hydroxide by thermal decomposition above 320°C. The latter is frequentiy used as a standard for spectrographic analysis of beryUium compounds. 

Electron Probe X-Ray Microanalysis (EPMA) is a spatially resolved, quantitative elemental analysis technique based on the generation of characteristic X rays by a focused beam of energetic electrons. EPMA is used to measure the concentrations of elements (beryllium to the actinides) at levels as low as 100 parts per million (ppm) and to determine lateral distributions by mapping. The modern EPMA instrument consists of several key components ... 

Samples Analyzed by Inductively Coupled Plasma (ICP) Metals — Where two or more of the following analytes are requested on the same filter, an ICP analysis may be conducted. However, the Industrial Hygienist should specify the metals of interest in the event samples cannot be analyzed by the ICP method. A computer print-out of the following 13 analytes may be typically reported Antimony, Beryllium, Cadmium, Chromium, Cobalt, Copper, Iron, Lead, Manganese, Molybdenum, Nickel, Vanadium, Zinc. Arsenic — Lead, cadmium, copper, and iron can be analyzed on the same filter with arsenic. 

This analysis shows that if the oxides of the two components of a binary alloy are mutually insoluble, and if one of the components has a much greater affinity for oxygen than the other, then the oxide of the baser metal will be formed exclusively even though it is present in the alloy in only a small amount. It seems that the importance of beryllium as an alloying constituent can be explained in this way. It has a high affinity for oxygen [p(BeO) = 10 atm at 1000°C] and also forms a highly protective oxide layer. The... 

Other fluorinated derivatives of acetylacetone are trifluoroacetylacetone (CF3COCH2COCH3) and hexafluoroacetylacetone (CF3COCH2COCF3), which form stable volatile chelates with aluminium, beryllium, chromium(III) and a number of other metal ions. These reagents have consequently been used for the solvent extraction of such metal ions, with subsequent separation and analysis by gas chromatography [see Section 9.2(2)]. 

The number of reported applications to analytical determinations at the trace level appear to be few, probably the best known being the determination of beryllium in various samples. The method generally involves the formation of the volatile beryllium trifluoroacetylacetonate chelate, its solvent extraction into benzene with subsequent separation and analysis by gas chromatography..61... 

Fluorimetry is generally used if there is no colorimetric method sufficiently sensitive or selective for the substance to be determined. In inorganic analysis the most frequent applications are for the determination of metal ions as fluorescent organic complexes. Many of the complexes of oxine fluoresce strongly aluminium, zinc, magnesium, and gallium are sometimes determined at low concentrations by this method. Aluminium forms fluorescent complexes with the dyestuff eriochrome blue black RC (pontachrome blue black R), whilst beryllium forms a fluorescent complex with quinizarin. 

Background current, 21, 65 Background subtraction, 40, 106 Bacteria electrode, 182 Band microelectrodes, 130, 135 Beryllium, 82 Bienzyme electrodes, 175 Biocatalytic devices, 172 Biological recognition, 171 Biosensors, 50, 171 Bipotentiostat, 106 Blood electrolyte, 165 Boltzmann equation, 19 Brain analysis, 40, 116 Butler-Volmer equation, 14... 

We originally proposed NNM to be present in metallic beryllium [30] based on analysis of the X-ray diffraction data measured by Larsen and Hansen [24], Based on Fourier maps and elaborate multipole least-squares modeling, indisputable evidence... 

Soft, silver white metal that is isolated in the tiniest of amounts. All isotopes are radioactive, the longest-lived has a half-life of 22 years. The element is an intermediate in the decay series of 235U. Strong alpha emitter that is used in radioactivation analysis and forms an effective neutron source with beryllium. 

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),... 

A new area of research concerns exposure assessment for beryllium in the production of nuclear weapons at nuclear defense industries. A safe level of exposure to beryllium is still unknown. Potential explanations include (1) the current exposure standard may not be protective enough to prevent sensitization, or (2) past exposure surveillance may have underestimated the actual exposure level because of a lack of understanding of the complexity of beryllium exposures. Task-based exposure assessment provides information not directly available through conventional sampling. It directly links exposure to specific activity associated with contaminant generation and provides in-depth evaluation of the worker s role in a specific task. In-depth task analysis is being used to examine physical, postural, and cognitive demands of various tasks. 

Beryllium (Be), 3 637-661. See also Beryllium compounds analysis, 3 645-647 chemical reactions, 3 639-640 in coal, 6 718-719 commercial grades, 3 644t economic aspects, 3 644-645 effect on copper resistivity, 7 676t fabrication, 3 642-644 in galvanic series, 7 805t handling, 3 647... 

Suarze DL. Beryllium, magnesium, calcium, strontium, and barium. In Bartels JM (ed.), Methods of Soil Analysis Part 3 Chemical Methods. Madison, WI Soil Science Society of America and American Society of Agronomy 1996, pp. 575-601. 

An analysis of the values taken by the different elements of the correlation matrices was recently reported [15] for the ground state of the Beryllium atom. This analysis suggested that the contributions of the 1 -, 2- and 3-body correlation effects differed according to the kind of orbitals involved in a given element. In particular, the highest occupied homo) and lowest empty (lumo) orbital of the HF configuration seemed to play an important role. 

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