Elemental characterization

Instrumental Methods for Bulk Samples. With bulk fiber samples, or samples of materials containing significant amounts of asbestos fibers, a number of other instmmental analytical methods can be used for the identification of asbestos fibers. In principle, any instmmental method that enables the elemental characterization of minerals can be used to identify a particular type of asbestos fiber. Among such methods, x-ray fluorescence (xrf) and x-ray photo-electron spectroscopy (xps) offer convenient identification methods, usually from the ratio of the various metal cations to the siUcon content. The x-ray diffraction technique (xrd) also offers a powerfiil means of identifying the various types of asbestos fibers, as well as the nature of other minerals associated with the fibers (9). 

PET fibers in final form are semi-crystalline polymeric objects of an axial orientation of structural elements, characterized by the rotational symmetry of their location in relation to the geometrical axis of the fiber. The semi-crystalline character manifests itself in the occurrence of three qualitatively different polymeric phases crystalline phase, intermediate phase (the so-called mes-ophase), and amorphous phase. When considering the fine structure, attention should be paid to its three fundamental aspects morphological structure, in other words, super- or suprastructure microstructure and preferred orientation. 

Kucera j (1995) Elemental characterization of new Polish and US NIST geological, environmental and biological reference materials by neutron activation analysis and comments on the methodology of interlaboratory comparisons. Chem Anal (Warsaw) 40 405-421. 

Trace element characterization represents concentrations of elements that are contaminated in materials or their leachates in a trace level, generally reported in units of mg/kg or mg/L. Although in minimum quantities, trace elements need to be characterized to assess the hazardous impact of the... 

Chen CY. AU-rich elements characterization and importance in mRNA degradation. Trends Biochem Sci 1995 20 465-470. 

If you stick to the definition of an allotrope being a modification of an element characterized by its x-ray crystal structure. Otherwise carbon may have more modifications, when counting all the different fullerenes and carbon nanotubes as allotropes. 

Williams, O. (1978). A Study of Obsidian in Prehistoric Central and Eastern Europe, and Its Trace Element Characterization. Unpublished PhD Thesis, Postgraduate School of Studies in Physics, University of Bradford. 

Mallory-Greenough, L. M. and Greenough, J. D. D. (1998). New data for old pots trace element characterization of ancient Egyptian pottery using ICP-MS. Journal of Archaeological Science 25 85-97. 

Middleton, W. D. and Price, T. D. (1996). Identification of activity areas by multi-element characterization of sediments from modern and archaeological house floors using inductively coupled plasma-atomic emission spectroscopy. Journal of Archaeological Science 23 673-687. 

ISO/TR 7073 1988 Recommended techniques for the installation of unplasticized poly (vinyl chloride) (PVC-U) buried drains and sewers ISO 7387-1 1983 Adhesives with solvents for assembly of PVC-U pipe elements -Characterization - Part 1 Basic test methods ISO 7508 1985 Unplasticized polyvinyl chloride (PVC-U) valves for pipes under pressure -Basic dimensions - Metric series... 

The response to pathogen infection involves not only some of the cA-elements characterized for the UV-light response but also additional regulatory elements related to pathogen-associated stimuli. These include the H-box and a TGAC (W-box) sequence that interacts specifically with a WRKY H-boxes have been associated with stress induction... 

Allotrope different forms of an element characterized by different structures Alloy a mixture of two or more metals, for example, zinc + copper = brass Alpha Decay nuclear process in which an alpha particle is emitted by the nucleus... 

Metal class of elements characterized by their ability to form positive ions, conduct heat and electricity, malleability, and luster Metallic Bond bond present in metals due to delocalized electrons moving throughout the metal lattice... 

Radionuclides Isotopes of elements characterized by spontaneous nuclear interconversions. 

Element characterization of sample tempera- ture K i Rockwell i value/ scale macro- measure- ment micro- measure- ment ... 

Ariola V, D Alessandro A, Lucarelli F, Marcazzan G, Mazzei F, Nava S, Garcia-Orellana I, Prati P, Valli G, Vecchi R, Zucchiatti A (2006) Elemental characterization of PM10, PM2.5 and PM1 in the town of Genoa (Italy). Chemosphere 62(2) 226-232... 

Capacitance — Property of a circuit element characterized by an insulating medium contained between two conductive parts. The unit of capacitance is a farad (F), named for the English scientist Michael Faraday. Capacitance values are more commonly expressed in microfarad ( iF), which is 10 of a farad. Capacitance is one means by which energy or electrical noise can couple from one electrical circuit to another. Capacitance between two conductive parts can be made infinitesimally small but may not be completely eliminated. 

Surface tractions or contact forces produce a stress field in the fluid element characterized by a stress tensor T. Its negative is interpreted as the diffusive flux of momentum, and x x (—T) is the diffusive flux of angular momentum or torque distribution. If stresses and torques are presumed to be in local equilibrium, the tensor T is easily shown to be symmetric. 

The non-diagonal submatrices j j>p and j>j p describe the optical coherences between the magnetic sublevels of the states J" and J. The submatrices j j"P and j>j>p describe the particles on levels J" and J respectively. Their diagonal elements characterize the populations of the respective sublevels M" and M, whilst the non-diagonal elements describe the Zeeman coherences. 

The use of ICP-MS for elemental characterization in beverages has been covered by a recent review that emphasized the applications in the area of fingerprinting and authenticity assessment [48], The combination of (multi)elemental/ isotopic analyses with powerful multivariate statistical methods can provide a solution for the authentication of food and beverages [49] and there is an increasing awareness of the potential of ICP-MS in this respect. Foods originating from... 

ICP-MS allows different quantification procedures to be used depending on the accuracy and precision required. The suitability of the semiquantitative mode of analysis of an ICP-MS instrument for multi-element characterization of fortified and table wines was evaluated by Almeida and Vasconcelos [83]. As compared to... 

---