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Notes on measurement

As has already become apparent from the example relating to the detection limit, two values play a crucial role when measuring the activity in a sample the background rate and the calibration factor. [Pg.471]

Modern systems store the last background value in each case automatical- [Pg.471]

The calibration factor is not only a function of the detector - sample geometry and the efficiency of the counter for the respective type of emitter and radiation energy it is influenced above all for alpha and beta measurements by the more or less uniform distribution of the [Pg.472]

Furthermore, the calibration factor must be determined for various residual quantities in the dish. With a 200 mm diam. dish the difference for example in the calibration factor between 0 g residue and 3 g residue [Pg.472]

These values have been available for a long time in tabular form. Nevertheless it is advisable to produce one s own calibration standards for the specific analytical conditions, as the surface structure, the residue material and the uniformity or otherwise of its [Pg.472]


Anon., Applications note on measurement of fat and total solids in mUk samples using a GQA-31 EL, Pacific Scientific Technical Paper NIR 4000, May 18, 1978. [Pg.435]

Write a short note on measurement of osmotic pressure. (C.C.S. Univ. 2008)... [Pg.147]

This section gives a listing of some basis sets and some notes on when each is used. The number of primitives is listed as a simplistic measure of basis set accuracy (bigger is always slower and usually more accurate). The contraction scheme is also important since it determines the basis set flexibility. Even two basis sets with the same number of primitives and the same contraction scheme are not completely equivalent since the numerical values of the exponents and contraction coefficients determine how well the basis describes the wave function. [Pg.85]

Hexachlorocyclotriphosphazene (cycHc trimer) is a respiratory irritant. Nausea has also been noted on exposure (10). Intravenous and intraperitoneal toxicity measurements were made on mice. The highest nonlethal dose (LDq) was measured as 20 mg/kg (11). Linear chloropolymer is also beUeved to be toxic (10). Upon organic substitution, the high molecular weight linear polymers have been shown to be inert. Rat implants of eight different polyphosphazene homopolymers indicated low levels of tissue toxicity (12). EZ has been found to be reasonably compatible with blood (13), and has lower hpid absorption than fiuorosihcone. [Pg.526]

European Community. 1993. "Technical Note on the Best Available Technologies to Reduce Emissions into Air from Coke Plants." Paper presented to BAT Exchange of Information Committee, Brussels, 1993. "Study on the Technical and Economic Aspects of Measures to Reduce the Pollution from the Industrial Emissions of Cokeries." Paper presented to BAT Exchange of Information Committee, Brussels. [Pg.145]

M. J, Hickman. Measurement of Humidity. Notes on Applied Science, no 4. N.itional Physical Laboratory, 1970. [Pg.1174]

As shown previously, vibrations can be displayed graphically as plots which are referred to as vibration profiles or signatures. These plots are based on measurable parameters (i.e., frequency and amplitude). Note that the terms profile and signature are sometimes used interchangeably by industry. In this chapter, however, profile is used to refer either to time-domain (also may be called time trace or waveform) or frequency-domain plots. The term signature refers to a frequency-domain plot. [Pg.674]

Note on the gravimetric standardisation of hydrochloric acid. The gravimetric standardisation of hydrochloric acid by precipitation as silver chloride is a convenient and accurate method, which has the additional advantage of being independent of the purity of any primary standard (compare Section 10.38). Measure out from a burette 30-40mL of the, say, 0.1M hydrochloric acid which is to be standardised. Dilute to 150 mL, precipitate (but omit the addition of nitric acid), and weigh the silver chloride. From the weight of the precipitate, calculate the chloride concentration of the solution, and thence the concentration of the hydrochloric acid. [Pg.481]

A note on the assays of coelenterazine and luciferase activity. The methods for measuring coelenterazine and the corresponding luciferases are given in Appendix C5. Special attention must be paid to the fact that coelenterazine in aqueous buffer solutions spontaneously emits a low level of chemiluminescence in the absence of any luciferase, which is greatly enhanced by the presence of various substances, including egg yolk, BSA and various surfactants (especially, hexadecyltrimethylammonium bromide). Therefore, the utmost care must be taken in the detection and measurement of a low level of... [Pg.164]

The observations of fine motor problems in infants born to heroin addicts has also been described by Wilson et al., in 1973. She notes the discrepancy between the gross motor skills of the infants and fine motor abilities during the first year. Furthermore, in 1979, Wilson et al, described the development of preschool children between 3 and 6 years of age, born to heroin-addicted mothers. They performed poorer on measures of visual, tactile, and auditory perception, were more active, and had... [Pg.261]

Special Note on Significant Figures Electronic calculators do not keep track of significant figures at all. The answers they yield most often have fewer or more digits than the number justified by the measurements. The student must keep track of the significant figures ... [Pg.22]

Note It is interesting to compare the calculation above based on measured interatomic distances... [Pg.408]

Figure 4. Isotopic mass-balance for measured 6 Fe values of ferric ( ) and ferrous ( ) Fe in solution as a function of Fe(II)/FeT ratios. Although the initial Fe isotope compositions of the fluids have 6 Fe values of 0%o (shown hy dotted mixing line), the lighter Fe isotopes are portioned into the ferrous species following attaimnent of isotopic equilihrium. The triangles (A) represent the calculated isotopic mass balance of the different solutions. Fractionations noted are measured values based on data for equimolar and higher Fe(II)/total Fe ratio experiments. (A) and (D) are for experiments with zero Cl at 22 and 0°C, respectively. (B) and (E) are experiments done with at 11 mM Cl at 22 and 0°C, respectively. (C) and (F) are experiments done with 111 mM Cl at 22 and 0°C, respectively. Modifled from Welch et al. (2003). Figure 4. Isotopic mass-balance for measured 6 Fe values of ferric ( ) and ferrous ( ) Fe in solution as a function of Fe(II)/FeT ratios. Although the initial Fe isotope compositions of the fluids have 6 Fe values of 0%o (shown hy dotted mixing line), the lighter Fe isotopes are portioned into the ferrous species following attaimnent of isotopic equilihrium. The triangles (A) represent the calculated isotopic mass balance of the different solutions. Fractionations noted are measured values based on data for equimolar and higher Fe(II)/total Fe ratio experiments. (A) and (D) are for experiments with zero Cl at 22 and 0°C, respectively. (B) and (E) are experiments done with at 11 mM Cl at 22 and 0°C, respectively. (C) and (F) are experiments done with 111 mM Cl at 22 and 0°C, respectively. Modifled from Welch et al. (2003).
For the blend uniformity application, the primary concern is overall heterogeneity within the sample. This is directly indicated by the width of the distribution and is quantitatively measured as the percent standard deviation relative to the mean (%SD). The %SD value obtained from the PLS scores distribution from each of the six imaged tablets is noted on the histograms in Figure 8.15(A-F). The value of %STD consistently decreases as the blending quality of the sample improves. [Pg.276]

Night vision improvement. In a doubleblind study, graduated THC administration at doses of 0-20 mg (as Marinol) on measures of dark adaptometry and scotopic sensitivity was evaluated. Field studies of night vision were performed among Jamaican and Moroccan fishermen, and mountain dwellers with the LKC Technologies Scotopic Sensitivity Tester-1 (SST-1). Improvements in night vision measures were noted after THC or cannabis. The effect was dose-dependent and cannabinoid-mediated at the retinal level k... [Pg.75]

Daabees determined the drug and its degradation product by second (D2) and third (D3) derivative spectrophotometry [18]. The methods were based on measuring the D2 and D3 amplitudes at 260 and 270 nm, respectively, for analytes dissolved in 0.1 N hydrochloric acid. No interference with the degradation product was noted. [Pg.272]

Data analysis. We use a combination of two movement detection algorithms (23) written in Madab environment (The MathWorks, Inc.) to accurately track movement of the heart edges see Note 10). Measurements of diastolic and systolic diameters as well as diastolic and systolic intervals, % fractional shortening (% PS), arrhythmicity index, and contraction direction and velocity are obtained as output from this analysis program. Heart rate is calculated as the inverse of the heart period where one period corresponds to a single diastolic interval plus subsequent systolic interval. % FS is quantified based on diameter measurements and is calculated as ((diastolic diameter-systolic diameter)/diastolic diameter) x 100 (%). Heart beat rhythmicity is quantified based on the standard deviation of the mean heart period normalized to the median heart period for each fly providing a dimensionless arrhythmicity index. [Pg.243]

L.133 Using two sets of backbone RDC data, collected in bacteriophage Pfl and bicelle media, they obtained order tensor parameters using a set of crystallographic coordinates for the structural model. This allowed the refinement of C -C bond orientations, which then provided the basis for their quantitative interpretation of C -H RDCs for 38 out of a possible 49 residues in the context of three different models. The three models were (A) a static xi rotameric state (B) gaussian fluctuations about a mean xi torsion and (C) the population of multiple rotameric states. They found that nearly 75% of xi torsions examined could be adequately accounted for by a static model. By contrast, the data for 11 residues were much better fit when jumps between rotamers were permitted (model C). The authors note that relatively small harmonic fluctuations (model B) about the mean rotameric state produces only small effects on measured RDCs. This is supported by their observation that, except for one case, the static model reproduced the data as well as the gaussian fluctuation model. [Pg.144]


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