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121.
The article considers the impact of the Health Action Zone (HAZ) in Plymouth through a theory-based evaluation that combines theories of change and realistic evaluation. The study assesses the impact of 37 projects sponsored by this HAZ. The extent to which these projects used a realistic evaluation/theories of change framework and achieved their objectives are evaluated. The impact of these projects on the three main objectives of Plymouth HAZ – developing partnership working; modernising the care system; and tackling health inequalities – is assessed and explanations for the success or failure of specific projects are identified.  相似文献   
122.
This study focused on gas chromatographic analysis of target compounds found in illicit amphetamine synthesised by the Leuckart reaction, reductive amination of benzyl methyl ketone, and the nitrostyrene route. The analytical method was investigated and optimised with respect to introduction of amphetamine samples into the gas chromatograph and separation and detection of the target substances. Sample introduction using split and splitless injection was tested at different injector temperatures, and their ability to transfer the target compounds to the GC column was evaluated using cold on column injection as a reference. Taking the results from both techniques into consideration a temperature of 250 degrees C was considered to be the best compromise. The most efficient separation was achieved with a DB-35MS capillary column (35% diphenyl 65% dimethyl silicone; 30 m x 0.25 mm, d(f) 0.25 microm) and an oven temperature program that started at 90 degrees C (1 min) and was increased by 8 degrees C/min to 300 degrees C (10 min). Reproducibility, repeatability, linearity, and limits of determination for the flame ionisation detector (FID), nitrogen phosphorous detector (NPD), and mass spectrometry (MS) in scan mode and selected ion monitoring (SIM) mode were evaluated. In addition, selectivity was studied applying FID and MS in both scan and SIM mode. It was found that reproducibility, repeatability, and limits of determination were similar for FID, NPD, and MS in scan mode. Moreover, the linearity was better when applying FID or NPD whereas the selectivity was better when utilising the MS. Finally, the introduction of target compounds to the GC column when applying injection volumes of 0.2 microl, 1 microl, 2 microl, and 4 microl with splitless injection respectively 1 microl with split injection (split ratio, 1:40) were compared. It was demonstrated that splitless injections of 1 microl, 2 microl, and 4 microl could be employed in the developed method, while split injection and splitless injections of 0.2 microl should be avoided.  相似文献   
123.
Kirn W  Cole W 《Time》2001,157(17):56-58
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124.
Reference material was synthesised for 21 substances that are frequently present as synthetic impurities, i.e. by-products, in illicitly produced amphetamine. Each of these substances is a typical by-product for at least one of the three approaches most often used to synthesise amphetamine, namely, the Leuckart, the reductive amination of benzyl methyl ketone, and the nitrostyrene routes. A large body of data on the substances was recorded, including the following: mass spectra, ultraviolet spectra, Fourier transform infrared spectra, infrared spectra in gas phase, and 1H NMR and 13C NMR spectra.  相似文献   
125.
The present study focused on the stability of 22 amphetamine impurities dissolved in six organic solvents: isooctane, toluene, ethanol, dichloromethane, ethyl acetate, and diethyl ether. The aim was to find the most inert, and thereby most suitable, solvent for amphetamine profiling. Mixtures of the impurities were prepared in the different solvents, and changes in the concentrations of the individual compounds over-time were monitored by gas chromatographic analysis after 0, 4, 12, 24, 48, and 96 h. Isooctane and toluene provided the most inert conditions, although, a few of the impurities were insufficiently stable in these two solvents. The present experiments were performed as a part of the development of a harmonized method for profiling of amphetamine. The results can be used to support the choice of organic solvents for sample preparation. They also provide information about the stability of the impurities that are found in profiles of illicit amphetamine. This is essential due to the fact, that unstable compounds can have a negative influence on the comparison of profiles.  相似文献   
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128.
Cole W 《Time》2006,167(6):56-58
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129.
A method has been developed for the analysis of arson accelerants in fire scene debris by vapour phase ultra-violet (UV) spectroscopy. The method is rapid, inexpensive, simple to use and is sufficiently sensitive and discriminating to be of use for the analysis of crime scene samples. Application to casework samples is described. On occasion, the method offers additional information to that which can be obtained by gas chromatography-flame ionisation detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS) and represents a useful adjunct to these techniques. In addition, the method offers advantages where the use of GC-MS analysis of arson accelerants in fire scene debris is not a practical proposition.  相似文献   
130.
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