RSD

The sfe of chlorpyrifos methyl from wheat followed by on-line Ic/gc/ecd has been investigated (93). Extraction profiles were generated to determine the maximum analyte recovery and the minimum extraction time. Using pure CO2, a 65% recovery of chlorpyrifos methyl spiked onto wheat at 50 ppb was reported. When 2% methanol was added to the CO2, the recovery from a one gram sample averaged 97.8% (n = 10, 4.0% RSD). 

ICP-SFMS (Thermo Finnigan, Flement) with cold vapour generation was developed with a guard electrode and a gold amalgamation device using an Au-sorbent for sample pre-concentration to improve the sensitivity. Instrumental parameters of ICP-SFMS such as take-up time, heating temperature of Au-sorbent, additional gas flow, and sample gas flow were optimized. Detection limit calculated as 3 times the standard deviation of 10 blanks was 0,05 ng/1, RSD = 7-9 %. 

As atomic fluorescence spectrometer a mercury analyzer Mercur , (Analytik-Jena, Germany) was used. In the amalgamation mode an increase of sensitivity by a factor of approximately 7-8 is obtained compared with direct introduction, resulting in a detection limit of 0,09 ng/1. This detection limit has been improved further by pre-concentration of larger volumes of samples and optimization of instrumental parameters. Detection limit 0,02 ng/1 was achieved, RSD = 1-6 %. 

As a result a new approaehes in DCP-ai e atomie-emission speetrometry were applied for Ca, Mg, Cu, Zn, Fe and P determination in blood semm and Ca, Mg, Cu, Zn, Fe, P, Mn, Pb, Cd, Sn, Sr et al. - in human and animals hair with relative standai d deviation (RSD) about 10-20 %. The aeeuraey eontrol has been realized by a eomparison of data produeed with the results of independent methods (atomie-absorption speetrometry and inverse voltammetry). 

For the bones the preferenee has been given to atomie-absorption speetrometry with flame and graphite furnaee atomization beeause of a strong effeet of ealeium and phosphorous on the analytieal signals of mieroelements under determination in DCP-ai e AFS. It has been shown that In the presenee of lanthanum ehloride no interferenee effeets were observed in flame AAS for Ca, Mg and Sr. FTA AAS has been used to determine Mn and Li in bones. RSD for FAAS determination of Ca, Mg, Sr were 3-6 %, as for Li and Mn -10-12%. 

The obtained analytical forms are used for quantitative determination of both Diclofenac natrium and Ibuprofen content in medicinal forms as well as for the testing uniformity of batching of the basic substance in tableted forms. The relative standard deviation (RSD) were 3,7-4,6 % (n = 5 P = 0,95). 

Accuracy and precision of the methods were checked by the added-found method and statistic treatment of the data of determinations (RSD ranged from 0.025 to 0.046). 

Where RISK = probability of eaneer, dimensionless C = Air eoiieeiUration, iiig/m3 CSF = Careinogeiiie slope faetor, RSDs(iiig/kg-d) ... 

Note The RSD is an estimate of tlie average daily dose of a careinogen tliat... 

Quaternary ammonium salts such as carcainium chloride (RSD 931) have been shown to be antitussive whilst having much reduced local anaesthetic activity. Whilst the molecular mechanisms underlying this antitussive activity is not understood, RSD 931 appears to be A8 fibre selective and may represent a novel class of antitussive drug. More recently JMF2-1 a lidocaine derivative that blocks Na+ channels has had beneficial effects in the airways without significant local anaesthetic activity. 

The partial pressures of 0, C>2, Pu, PuO, and Pu02 were calculated as functions of T (1500 T 4000 K) and x (0.005 x 0.30), with particular emphasis on 0.005 x 0.10. Preliminary calculations at 5000 K yielded unreasonably high oxygen pressures and vapor densities such that an upper temperature limit of 4000 K was selected. Tables presenting selected results are given In ANL-CEN-RSD-82-1 (21). 

Green, D. W. Leibowitz, L. Argonne National Laboratory Report ANL-CEN-RSD-81-1, 1981. 

The accuracy and precision of the determinations were investigated. Recovery was found to be 101 2.0% for a range of volumetrically mixed samples and the relative standard deviation (RSD), for a standard injected 23 times over a period of 4.5 months, was found to be 1.1%. It should be noted that the performance of a method for samples based on standard materials may not be attainable when real samples are being determined and further method development may be required. 

RSD, relative standard deviation = (standard deviation/mean) x 100. Deviation = [(mean — nominal)/nominal] x 100. 

The relative standard deviation RSD (also known as the coefficient of variation, c.o.v., or CV), which is frequently used to compare reproducibilities, is calculated as... 

The relative standard deviation RSD (or c.o.v. = coefficient of variation ) is constant over the whole range, such as in many GC methods, that is, the standard deviation Sy is proportional to y. 

The RSD is small in the middle and large near the ends of the linear range, as in photometry. 

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