Standards for chemical analysis

European regulations set the limit for azaspiracid toxins content in shellfish that is to be destined to human consumption in 160 pg of azaspiracid eqnwalents/kg in the whole body or any part edible separately (EU 2002). This limit has a higher valne than the NOEL to allow for detection by mouse bioassay, the most commonly nsed method due to the lack of standards for chemical analysis. 

Organic coatings are applied by painting, powder coating. E-coating, plasma polymerization, and sol-gel coating [50]. The first step in painting is the selection of the primer. ASTM standards for chemical analysis of paints and paint materials are summarized in Table 13.2. 

Table 13.2 ASTM Standards for Chemical Analysis of Paints and Paint Materials Designation Title...

Sumner LW, et al. Proposed minimum reporting standards for chemical analysis Chemical Analysis Working Group (CAWG) Metabolomics Standards Initiative (MSI). Metabolomics 2007 3 211-221. 

A. W.,ReiIy,M.D.,Thaden, J.J.,Viant,M.R. (2007) Proposed minimum reporting standards for chemical analysis. Metabolomics, 3, 211-221. 

Sumner L, Amberg A, Barrett D, et al. (2007) Proposed minimum reporting standards for chemical analysis. Metabolomics 3 211-221 Van Loo J, Cummings J, Delzenne N, et al. (1999) Functional food properties of non-digestible oligosaccharides a consensus report from the ENDO project (DGXIIAIRII-CT94-1095). Br J Nutr 81 121-132... 

X-ray photoelectron spectroscopy (XPS), also called electron spectroscopy for chemical analysis (ESCA), is described in section Bl.25,2.1. The most connnonly employed x-rays are the Mg Ka (1253.6 eV) and the A1 Ka (1486.6 eV) lines, which are produced from a standard x-ray tube. Peaks are seen in XPS spectra that correspond to the bound core-level electrons in the material. The intensity of each peak is proportional to the abundance of the emitting atoms in the near-surface region, while the precise binding energy of each peak depends on the chemical oxidation state and local enviromnent of the emitting atoms. The Perkin-Elmer XPS handbook contains sample spectra of each element and bindmg energies for certain compounds [58]. 

Standard test methods for chemical analysis have been developed and pubUshed (74). Included is the determination of commonly found chemicals associated with acrylonitrile and physical properties of acrylonitrile that are critical to the quaUty of the product (75—77). These include determination of color and chemical analyses for HCN, quiaone inhibitor, and water. Specifications appear in Table 10. 

Standard Test Methods For Chemical Analysis of Magnesium and Magnesium Alloys, ASTM E-35 to 88, American Society for Testing and Materials, Philadelphia, Pa., 1992. 

Applications of EELS for Chemical Analysis. Apart from the fact that it is an absolute technique requiring no standard for calibration the special advantage possessed by EELS as a means of chemical analysis is that it combines sensitivity with spatial resolution. It is, in a literal sense, an ultramicro method with... 

FIGURE 1.16 Configuration and operational details of online introduction of internal standard for quantitative analysis of drugs from biological matrices.118 (Reproduced with permission from the American Chemical Society and the authors.)... 

Reference ASTM 114—00, Standard Test Method for Chemical Analysis of Hydraulic Cement. As suggested in this document, the sample should not be a slag cement sample. Your instructor may choose to dispense... 

Finding a Method Various organizations publish volumes of methods for chemical analysis. One of the most well known is the American Society for Testing and Materials, or ASTM. The ASTM is a not-for-profit organization that provides a forum for producers, users, and consumers, to write standards for materials, products, systems, and services. The ASTM (Figure 5.19) publishes standard test methods encompassing metals, paints, plastics, textiles, petroleum, construction, energy, the environment, consumer products, medical services and devices, computerized systems, electronics, and many other areas. More than 10,000 ASTM standards are published each year in the 72 volumes of the Annual Book of ASTM Standards. Individual standards are also available. 

Dots are experimental points, and error bars extend 1 standard deviation about the mean. Nate that the scale on the abscissa is logarithmic /From 6. Kratochvil and J. K. Taylor, "Sampling for Chemical Analysis," Anal. Chem. 1981, 53, 925A National Bureau of Standards Internal Report 80-2164. 1980, p. 66.]... 

The British equivalent to ISO 2781 is BS 903 Part Al2 which is identical to the international method. Rather surprisingly, ASTM does not appear to have a specific method for density at the present time. There is, however, a section on density in the standard on chemical analysis of rubber products, D2973, which briefly gives methods by pycnometer, hydrostatic weighing and a compressed volume densimeter. The weighing method does not mention the use of a sinker for densities less than 1. There is also a method for density of rubber chemicals, D1817)4, which uses the pycnometer method and, interestingly, specifies a vacuum pump to remove air before the measurement.. 

An internal standard is a compound that is not present in the sample, but is chemically and physically similar to the analytes of interest. A fixed quantity is incorporated into the calibration solutions. The same concentration of internal standard is added to the samples during extraction to compensate for analyte recovery and injection variability. As seen in Figure F2.3.I, Echinenone, which is not typically found in foods, is used as the internal standard. Unfortunately, compounds which may be used as internal standards for carotenoid analysis are not readily available commercially. 

In a method proposed by Booth et al. (141) for the determination of phylloquinone in various food types, extracted samples are subjected to silica solid-phase extraction followed, in the case of meat or milk samples, by further purification using reversed-phase solid-phase extraction or liquid-phase reduction extraction, respectively. The final test solution is analyzed by NARP-HPLC, and the fluorescent hydroquinone reduction products of phylloquinone and the internal standard are produced online using a postcolumn chemical reactor packed with zinc metal. 2, 3 -Dihydrophylloquinone, a synthetic analog of phylloquinone, is a suitable internal standard for the analysis of vegetable juice, whole milk, and spinach. Another synthetic analog, Ku23), is used for the analysis of bread and beef, because a contaminant in the test solution coelutes with dihydro-phylloquinone. 

After selection, the shale rocks were crushed, sieved, and divided into small samples by riffling. The shale samples weighed 2.5-3 g and were —6+10 U.S. Standard sieve size. The average composition of random samples chosen for chemical analysis is given in Table I. 

ASTM D-5369. Standard Practice for Extraction of Solid Waste Samples for Chemical Analysis Using Soxhlet Extraction. 

For each analytical measurement, it should be possible to relate the result of the measurement back to an appropriate national or international measurement standard through an unbroken chain of comparisons. For measurement of weight, this would be the kilogram standard in Paris, or for amount of substance it should be the SI unit, the mole. If calibrated by an accredited body, the balance is an instrument which can provide measures of weight which are traceable to national measurement standards. Instruments for chemical analysis must be calibrated by the use of certified reference materials, or other suitable reference materials. 

This work began as a slim booklet prepared by one of the authors (T.J.B.) to accompany a course on chemical instrumentation presented at the National Institute of Standards and Technology, Boulder Laboratories. The booklet contained tables on chromatography, spectroscopy, and chemical (wet) methods, and was intended to provide the students with enough basic data to design their own analytical methods and procedures. Shortly thereafter, with the co-authorship of Professor Paris D.N. Svoronos, it was expanded into a more extensive compilation entitled Basic Tables for Chemical Analysis, published as a National Institute of Standards and Technology Technical Note (number 1096). That work has now been expanded and updated into the present body of tables. 

Bruno, T.J. and Svoronos, P.D.N., Basic Tables for Chemical Analysis, National Bureau of Standards Technical Note 1096, April 1986. 

Macroscopic methods for chemical analysis essentially take either all of the particulate matter sampled or a significant protion of it for bulk analysis. Traditionally, this has been approached by the application of standard microchemical techniques of wet chemistry. The unique analytical requirement for aerosol particle samples is the microgram quantities collected. The analytical methods adopted must be capable of detecting these quantities in... 

The analytical methods that can be used are from Test Methods for the Evaluation of Solid Waste, Physical/Chemical Methods (SW-846, EPA-600/4-79/020) Standard Methods for Chemical Analysis of Water and Wastes (EPA-600/4-79/020) Standard Methods for the Examination of Water and Wastewater or American Society for Testing and Materials Standard Methods. 

All of the treated zeolite solids, both "filtrate" samples and "slurry" samples, were further analyzed by X-ray powder diffraction. The chemical compositions were determined by standard wet chemical analysis, and the filtrates were analyzed for Si02 and AI2O3 following titration. The results show that crystallinity was fully maintained in the solids and that the chemical reactions described in this work are confirmed by the analytical data and mass balances. 

By means of the microprocessors built into recent instruments, operations such as calibration and checking of stability have been simplified. The analyst needs only to use universally accepted standard methods which can be easily applied to as many classes of materials as possible. Such methods will be described in the following sections for chemical analysis in the ferrous metallurgy industry. 

Until recently, obtaining high-quahty chemical standards for the analysis of PFCs was difficult. Although some standards were available commercially, others were available only from manufacturers, and had variable purity and isomer profiles [94,128]. These impurities and structural isomers were not always well documented and could contribute to inaccurate analytical results. For example, shorter chain PFCA impurities observed in a chemical standard of PFTA could result in a negative bias of unknown proportions in quantitation when mixed standard solutions are used without correction [94]. Today, an increasing... 

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