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排序方式: 共有3898条查询结果,搜索用时 78 毫秒
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Richter EM Augelli MA Kume GH Mioshi RN Angnes L 《Fresenius' Journal of Analytical Chemistry》2000,366(5):444-448
The development of a new methodology for the construction of very efficient flow cells for mercury detection by potentiometric stripping analysis, employing the thin gold layer of recordable CDs as working electrode is reported. This new source of electrodes (CDtrodes) show very attractive performance, similar to that obtained with commercial gold electrodes, with superior versatility. The low cost of this new source of "gold electrodes" allows a frequent replacement of the electrode, avoiding cumbersome clean-up treatments. Various experimental parameters have been optimized to yield low detection limits (0.25 ng/mL of mercury for 5 min deposition at 0.3 V) and good precision (standard deviation of 1.9% was obtained for 15 repetitive measurements using 10 ng/mL of mercury). Standard curves were found to be linear over the range of 0.5-100 microg L(-1) of mercury. The flow cells developed were used for the quantification of mercury in oceanic and tap water. 相似文献
96.
D W Later B E Richter D E Knowles M R Andersen 《Journal of chromatographic science》1986,24(6):249-253
Three classes of drugs were screened for analysis feasibility by capillary column supercritical fluid chromatography. These included steroids, therapeutic antibiotic drugs, and drugs of abuse, such as cannabinoids. Supercritical fluid carbon dioxide was used as the mobile phase in conjunction with a methylpolysiloxane stationary phase capillary column and a flame ionization detector. All compounds considered were analyzed either as single component solutions, simple mixtures, or in actual complex mixtures. 相似文献
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de la Vaissiere C Luth V Abrams GS Amidei D Baden AR Barklow T Boyarski AM Boyer J Breidenbach M Burchat P Burke DL Butler F Dillon JW Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding LG Hanson G Haggerty J Herrup D Himel T Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Matteuzzi C Nelson ME Ong RA Perl ML Richter B Ross MC Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Yelton JM Wood DR 《Physical review letters》1985,54(19):2071-2074
100.
A. Henrion Gunther Dube Wolfgang Richter 《Analytical and bioanalytical chemistry》1997,358(4):506-508
The uncertainty budget of the determination of cholesterol in a reference material (freeze-dried human serum) by isotope
dilution mass spectrometry (IDMS) was evaluated. Measurements were run on a GC/quadrupole MS. A nested experimental design
combined with a corresponding model for the analysis of variance (ANOVA) revealed the components making up the total uncertainty
of the determinations. The coefficient of variation (CV) of the sole GC/MS-step was 0.47%, while that of the sample preparation
including hydrolyzation, extraction and derivatization was 0.84%. This made the in-laboratory (overall) CV 0.96%. In addition,
there was a vial-to-vial effect of 1.00% probably due to both inhomogeneity of the pooled material and lack of reproducibility
of the filling procedure (including freeze drying) of the supplier as well as the reconstitution prior to use in the laboratory.
These contributions sum up to an overall CV of a single determination of about 1.4%.
Received: 17 October 1996/Revised: 14 November 1996/Accepted: 18 November 1996 相似文献