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81.
Isobutane CIMS is useful for determining the molecular weight of morphine and its derivatives, as well as for identifying labile acyl substituents on morphine's O-6 position. Furthermore, this technique will provide information relating to the presence or absence of pi-bonding on the C-7 carbon. The spectra of morphine derivatives can be further simplified by employing ethylenediamine as a reagent gas. This approach proves useful for eliciting or confirming molecular weight information from the CI spectrum. In our laboratory extended use of ethylenediamine has been accomplished without any deleterious effect on the mass spectrometer's source or its vacuum system. The utility of isobutane and ethylenediamine CI rests with its ability to supply the analyst with structure elucidation data that may be used to complement more detailed information extractable from either EI or CE spectra. This aspect of mass spectrometry is especially useful when one is dealing with an unknown member of a particular class of organic compounds. 相似文献
82.
Joseph Sanders V. Lee Hamilton Gennady Denisovsky Naotaka Kato Mikio Kawai Polina Kozyreva Takashi Kubo Michael Matskovsky Haruo Nishimura Kazuhiko Tokoro 《Law & social inquiry》1996,21(4):815-855
The decision rules individuals use to judge wrongdoing committed inside corporations and other hierarchical organizations are not well understood. We explore this issue by asking random samples of individuals in Moscow, Tokyo, and Washington, D. C., to respond to four short vignettes describing acts of wrongdoing by people in corporations. The vignettes are experiments that manipulate the actor's mental state, the actor's position in the organization, and whether the actor's decision was influenced by others in the organization. We examine (1) the distribution of responsibility among people in the organization, (2) how individual responsibility affects the attribution of responsibility to the organization itself, and (3) cross-national differences in attributions. We find that both what the actors did (their deeds) and the position they occupied (their roles) significantly influence the responsibility attributed to them. The responsibility attributed to the organizations themselves is a function of the responsibility attributed to the actors inside the organization, but not a function of the independent variables in the experiments. Cross-national differences emerge with respect to the responsibility assigned both to individuals and to the organizations themselves. We discuss implications of these results for past and future work. 相似文献
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H E Hamilton J E Wallace E L Shimek P Land S C Harris J G Christenson 《Journal of forensic sciences》1977,22(4):697-707
Maximal urinary excretion of unchanged cocaine occurred within 2 h of the intranasal absorption of 1.5 mg/kg body weight of cocaine hydrochloride, and diminished rapidly thereafter. Excretion of benzoylecgonine was maximal 4 to 8 h following administration of the drug and diminished slowly over an interval of several days. Peak cocaine and benzoylecgonine concentrations observed were 24 and 75 microgram/ml, respectively. Benzoylecgonine/cocaine ratios were too varied to allow estimation of cocaine concentrations from benzoylecgonine concentration data or vice versa. Benzoylecgonine concentrations generally exceeded the corresponding cocaine values by a wide margin, but excretion of free cocaine in the absence of benzoylecgonine was observed in one subject. Cocaine was generally detected for only approximately 8 h, and for a maximum of 12 h, whereas benzoylecgonine was generally detected by chromatographic or enzyme immunologic assays for 48 to 72 h. Benzoylecgonine was positively identified in urine by raidoimmunoassay for 96 to 144 h after dosing. 相似文献
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Due to their widespread use in domestic and commercial premises, polyurethane foams, as either fragmented or bulk foam, are types of evidence commonly found at crime scenes. The traditional approach to determining the evidential value of polyurethane foam (PF) involves comparing recovered and control fragments under low and high magnification, under various lighting conditions, as well as the comparison of their respective dye spectra. As with most forms of trace evidence, chemical comparison is also desirable. In this work, two approaches to chemically comparing foam fragments were investigated, i.e. inductively coupled plasma–optical emission spectrometry (ICP–OES) analysis of the Tin (Sn) content in different foam types; and gas chromatography–flame ionization detection (GC–FID) analysis of soluble components in PFs mobilized by dichloromethane. Seven different foam types were studied and their Sn content was found to be different. They also produced characteristic GC–FID chromatographic profiles whose compounds were identified with gas chromatography–mass spectrometry (GC–MS) analysis. This study suggests that incorporating chemical data obtained from GC–FID/GC–MS and ICP–OES into a case involving PF could be advantageous, as this will enable the forensic scientist to broaden the comparison between control and recovered fragments, and further assess the strength of the evidence. However, ICP–OES analysis is a destructive technique with a relatively short sample turnaround time, whilst GC–FID analysis is more time-consuming and non-destructive, requiring corroboration with GC–MS data. The values of these two analytical techniques in the forensic chemical characterization of PFs are discussed. 相似文献
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