Occupational disorder

The R-M-Z-X (M = Cu, Ag Z = Si, Ge, Sn, X = S, Se) systems have been investigated mainly across the R2X3-M2X-ZX2 sections. No quaternary compounds are known for Te systems. Quaternary compoimds that form in these systems are listed in Table 38. Among all of these 105 quaternary chalcogenides only four compoimds crystallize in SG other than P63. In several series of the silver compounds, occupational disorder for the silver atom has been foimd. 

The structure of seelite, Mg[(U02)(As04)i x(As03)x]2(H20)4, shows substitution on the tetrahedral position in the uranophane sheet-anion topology, rather than the pentagonal bipyramidal position. In seelite (not illustrated), As is disordered with As over the single As site in the structure. The site occupancy disorder of arsenite for arsenate is accompanied by disorder of the interlayer contents, which ideally contain Mg in octahedral coordination by H2O groups [180]. 

Atoms j and f are distributed in the lattice in an ordered fashion. This usually means that the incorrect space group symmetry was used to describe the crystal structure. The symmetry therefore, should be lowered by modifying or removing those elements that cause atoms to overlap. Yet another possibility is the so-called statistical mixing of various atoms in the same site. It may be observed when different unit cells contain two or more types of atoms in the same position. In the most general case, the occupational disorder can be expressed as ... 

This formula has been confirmed fi om single crystal diffraction data (Rp = 2.2 %), which give x = 0.202(3). The population of the Mn2 site is 0.792(4), slightly lower than expected 1 - 2/3x = 0.865. A small difference is acceptable because a tiny single crystal may not be representative of a large polycrystalline sample, especially in the case of occupational disorder. 

Secondly, by introducing these extra empty/occupied sites, the entropy of the system increases this is termed occupational disorder in this work. 

TABLE 2 Descriptions of Various Occupational Disorders and Diseases Not Included in Table 1... 

Because there is no occupational disorder, the diffuse scattering in Fig. 4a is essentially made up of terms from the second-order diffuse component I2 (Eq. 7). Because this is a sum of cosine terms, the intensity is symmetric about Bragg peak positions. This is true for the strong anisotropic peaks that suiTound some strong Bragg peaks... 

This is in full agreement with the data on RFeeAlg. In the latter case indications for the presence of frustration in the Fe system as well have been seen. The comparison with YFe4Alg shows that this must be due to the occupational disorder in the 8j sublattice, wiiich has also been deduced from theory (Felner et al. 1981). 

Hendrick, David, William Beckett, et al.. Occupational Disorders of the Lung, Saunders, Philadelphia, PA, 2002. 

Therefore, RB allow identifying of the dependence relationships among different causes of accidents and occupational disorders. These information—usually are not provided by conventional statisc methods applied in the occupational risk area—allow to develop an more realistic causal model (Martin et al., 2009). 

Therefore, it is possible to understand that the risk analyze through BN may be used as a tool of decision making, because through it were identify what factors of risk of specific activity and how each factor may influence on occurrence of accidents and occupational disorders, providing subsidies to mitigate its common assumptions (Zhao et al., 2012 Martin et al., 2009 Ti e et al. 2013). 

Occupational risks are elements inherent in the systematic of the work to identify and quantify these risks provide subsides for an effective action to try to prevent accidents and/or mitigate its effects. In this perspective, RB may become robust tools to analyze occupational risks to present the following characteristics (1) Considers dependence relationships among variables allowing the identification of a causal model (2) Considers a sequential of hannful events and its repercussion about accidents and occupational disorders (3) Uses qualitative and quantitative data, covering all the complexity of the system (4) Allows to integrate several hypotheses to determine the probability of a risk event. These characteristics make RB a reliable and efficient modeling tool of the occupational risks. 

Nemery B (2002) Toxic pneumonitis. In Hendrick DJ, Burge PS, Beckett W, Churg A (eds) Occupational disorders of the lung. Recognition, management, and prevention. WB Saunders-Harcourt Pubhshers, London, pp 201-219 Nemery B (2003) Reactive fallout of World Trade Center dust. 

Some 4503, 5 perovskite-structured materials, where A and B represent larger and smaller cations, are ionic conductors, while some other 503 s perovskite-type compounds are mixed conductors. Heavy elements such as La and Ba occupy the A site, but because the mobile O anion is a light element, conventional X-ray powder diffractometry is not sensitive to positional and occupational disordering of oxide ions. To investigate the diffusion path of mobile oxide ions, and structural disorder and crystal structure in perovskite-structured ionic and mixed conductors [5, 6, 8, 10-14], we applied a high-temperature neutron powder diffraction method. Our reasons for choosing this method were as follows [24] ... 

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