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721.
Seven ethyl homologues of known tropane esters have recently been detected as impurities in the gas chromatographic signature profiles of authentic Peruvian illicit cocaine base and hydrochloride exhibits. Peruvian cocaine base processors are now known to use ethanol for the purification of crude cocaine base. This process is referred to as the "base lavada" or "washed base" process and is a recent substitute method for the potassium permanganate oxidation purification methodology. Seven ethyl ester homologues were formed in illicit cocaine from the transesterification of known tropane methyl esters or possibly ethyl esterification of their respective tropane C-2 carboxylic acids in the presence of ethanol. Exhibits containing these compounds were subjected to gas chromatographic-mass spectrometric analyses to determine their identity and were subsequently synthesized to verify their structures. Quantitative determinations were obtained from ion-pair chromatography isolation followed by gas chromatography with flame ionization detection. Specifically, hexanoylecgonine ethyl ester, cocaethylene, cis-cinnamoylecgonine ethyl ester, trans-cinnamoylecgonine ethyl ester, 3',4',5'-trimethoxybenzoylecgonine ethyl ester, cis-3',4',5'-trimethoxycinnamoylecgonine ethyl ester, and trans-3',4',5'-trimethoxycinnamoylecgonine ethyl ester were detected and characterized. When present, these compounds were detected at levels ranging from 8.6 x 10(-4) to 9.3 x 10(-1)% relative to cocaine. 相似文献
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Plague is a deadly disease of obvious concern to individuals, communities, and public health officials. The rapid recognition of plague victims is of paramount importance in saving the lives of the victims and in the protection of contacts. Three autopsied plague cases have been presented and the pathological features have been discussed. 相似文献
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E. Terrence Jones 《Journal of criminal justice》1976,4(4):333-340
A longitudinal analysis of the changes in crime rates between the late 1950s and 1970 in the 155 largest U.S. cities indicates that (1) there is virtually no relationship between the four major crimes against persons although there is strong mutual association between the four major crimes against property; (2) changes in racial composition account for more variation in changes in crime than do changes in income, thereby suggesting the need for more detailed studies of the noneconomic ways in which a city's racial composition affects crime incidence; and (3) there is a modest relationship between changes in the number of male youth and changes in certain types of crime. Since these findings are based on highly aggregated data with both known and unknown measurement errors, they must be treated cautiously. 相似文献
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An Alcolmeter Pocket Model breath alcohol device, based on an electrochemical (fuel cell) oxidation principle for ethanol analysis, has been evaluated under in vitro conditions. The result of a test is displayed on an analogue meter within 20 – 30 seconds after sampling; replicate tests may be made within 3 – 5 minutes. The electrochemical detector used was found to respond to acetaldehyde, methanol, isopropanol and n-propanol vapours besides ethanol, but it was insensitive to acetone vapour. The Alcolmeter response with a 0 – 2.0 mg/ml scale was linearly related to ethanol vapour concentration up to 1.0 mg/ml blood alcohol equivalent concentration; above this level the response was curvilinear, the Alcolmeter reading being too low. The standard deviation of an ethanol vapour determination in vitro was ±0.0175 mg/ml at a mean concentration of 0.902 mg/ml. The accuracy of the device expressed as percent recovery at 0.50, 1.0 and 1.4 mg/ml blood alcohol concentrations was 96.8%, 98.3%, and 88.3%, respectively. When the Alcolmeter was calibrated at 0.50 mg/ml and used occasionally each day over an 18-day period, the drop in initial calibration was 0.01 mg/ml per week. 相似文献