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S. Begum  J.P. Lay  W. Klein  F. Korte 《Chemosphere》1977,6(11):711-723
14C-Chloralkylene-9 was applied to rats for 35 days (2 ppm/day/animal)2. GC-Mass Spectra indicated oxygenated components of chloralkylene-9 in urine and feces. The urinary metabolites were characterized to be mono-, di- and trihydroxy 2,4′-dichlorobiphenyls. The feces contained mainly those metabolites in which the side chain of mono-, di- and tri-isopropyl 2,4′-dichlorobiphenyl was oxidized. Different metabolic products containing alcoholic, aldehydic and carboxylic side chains were detected. Metabolites with unsaturated side chains were also detected.The GC-Mass spectroscopic analysis of chloroalkylene-9 residue showed the major component consisted of di- and tri-isopropyl 2,4′-dichlorobiphenyl. 2,4′-dichlorobiphenyl and monoisopropyl 2,4′-dichlorobiphenyl were found to comprise a smaller percentage of the total residue. There was also an indication of isomerization of 2,4′-dichlorobiphenyl.  相似文献   
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A quantitative risk assessment (QRA) tool has been developed by TNO for the external safety of industrial plants with a dust explosion hazard. As a first step an industrial plant is divided into groups of modules, defined by their size, shape, and constructional properties. Then the relevant explosion scenarios are determined, together with their frequency of occurrence. These include scenarios in which one module participates, as well as domino scenarios. The frequency is partly based on casuistry.

A typical burning velocity is determined depending on the ignition type, the dust properties and the local conditions for flame acceleration. The resulting pressure development is predicted with the ‘thin flame model’. Module failure occurs when the explosion load exceeds thresholds, which are derived from single degree of freedom (SDOF) calculations for various types of modules. A model has been developed to predict the process of pressure venting after module failure and the related motion of launched module parts.

The blast effects of the primary explosion are based on results from calculations with BLAST3D. The blast and flame effects of the secondary external explosion due to venting are calculated using existing models. The throw of fragments and debris is quantified with a recently developed model. This model is based on trajectory calculations and gives the impact densities, velocities, and angles as output. Furthermore the outflow of bulk material is taken into account. The consequences for external objects and human beings are calculated using existing models. Finally the risk contours and the Societal risk (FN curve) are calculated, which can be compared to regulations.  相似文献   

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Management of the land–sea interface is essential for global conservation and sustainability objectives because coastal regions maintain natural processes that support biodiversity and the livelihood of billions of people. However, assessments of coastal regions have focused strictly on either the terrestrial or marine realm. Consequently, understanding of the overall state of Earth's coastal regions is poor. We integrated the terrestrial human footprint and marine cumulative human impact maps in a global assessment of the anthropogenic pressures affecting coastal regions. Of coastal regions globally, 15.5% had low anthropogenic pressure, mostly in Canada, Russia, and Greenland. Conversely, 47.9% of coastal regions were heavily affected by humanity, and in most countries (84.1%) >50% of their coastal regions were degraded. Nearly half (43.3%) of protected areas across coastal regions were exposed to high human pressures. To meet global sustainability objectives, all nations must undertake greater actions to preserve and restore the coastal regions within their borders.  相似文献   
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