Showing papers on "Calibration curve published in 1971"
TL;DR: In this paper, the interpretation of the hot wire signal from a single hot wire in terms of a universal function is described, and the calibration curves for probes with nominally the same geometry have been studied for deviations in the shape of calibration curves, yaw dependence and the effect of angle of incidence.
Abstract: This paper describes the interpretation of the hot wire signal from a single hot wire in terms of a universal function. The calibration curves for probes with nominally the same geometry have been studied for deviations in the shape of calibration curves, yaw dependence and the effect of angle of incidence. From these results the basic equations for the interpretation of the signal from normal and yawed hot wires have been derived.
73 citations
TL;DR: In this paper, it is recommended that the temperature dependence of the calibration curve did not agree with a theoretical expression developed elsewhere, and that the instrument drift, which is frequently observed, should be reduced to a low and relatively steady value before measurements, periodically checked during measurements, and allowed for in calculations of leaf resistance.
52 citations
TL;DR: In this article, a predicted polyethylene molecular weight calibration is obtained from the experimental polystyrene standards calibration using equations which assume that hydrodynamic volume and the unperturbed mean-square end-to-end distance are universal calibration parameters.
23 citations
01 Feb 1971
TL;DR: In this paper, a general method for obtaining gel permeation chromato-graphic (GPC) molecular weight and hydrodynamic volume (HDV) calibration curves for polymer-solvent systems where primary polymer standards are unavailable is proposed.
Abstract: A general method is proposed for obtaining gel permeation chromato-graphic (GPC) molecular weight (MW) and hydrodynamic volume (HDV) calibration curves for polymer-solvent systems where primary polymer standards are unavailable. The method is demonstrated by using a HDV calibration curve based on polystyrene in tetrahydrofuran (THF), in conjunction with integral distribution curves of elution volume for poly(methyl methacrylate) (PMMA) in THF and in 2,2,2-tri-fluoroethanol (TFE) for the generation of a HDV calibration curve in TFE. Transformation methods for generating secondary MW calibration curves from HDV calibration curves are discussed and applied to PMMA in THF and TFE, and to poly(trimethylene oxide), poly(vinyl acetate), and certain polyamides in TFE. The utility and reliability of the secondary calibration curves are demonstrated by comparing MW average and intrinsic viscosites obtained by GPC and by the classical methods. Molecular structural differences among th polyamide samples asso...
20 citations
TL;DR: Methods are discussed for determining the radiation-produced change in molarity from the actual calibration curve, and a method of normalization of measured absorbances is suggested.
Abstract: A systematic error in the spectrophotometric measurement of ferric ion concentrations in the ferrous sulphate dosemeter may be made by an incorrect evaluation of a non-linear spectrophotometric calibration curve. Methods are discussed for determining the radiation-produced change in molarity from the actual calibration curve, and a method of normalization of measured absorbances is suggested. Normalization factors, converting measured absorbances into normalized values, can either be calculated by choosing a reference value of the molar extinction coefficient, or can be determined by comparative absorbance measurements on two spectrophotometers, one of them to be a precision instrument. Normalized absorbances are proportional to molarity and may be considered to be free of errors due to instrumental parameters and inaccuracies in acidity and temperature of solutions, and of errors in molarity if derived by comparative measurements.
20 citations
TL;DR: A number of methods have been developed for combining the universal calibration curve with measurable parameters of the polymeric material (such as intrinsic viscosity, number average molecular weight and weight average molecular weights) to calculate molecular weight distributions.
19 citations
12 citations
TL;DR: The 10·82 MeV gamma rays emitted in the prompt (n, γ) reaction on the nitrogen are used to determine the content of nitrogen in organic materials to prepare the calibration curve.
11 citations
TL;DR: In this article, a spectrophotometric procedure for the determination of vanadium and for the simultaneous determination of iron and vanadium by means of two wavelength measurements, at 470 and 540 nm or 418 and 470 nm.
10 citations
TL;DR: In this article, the authors discuss the effects of gender stereotypes on gender stereotypes in the context of gender discrimination in the media. But they do not discuss the effect of gender bias on gender identification.
Abstract: ナイロン6のグリセリンおよびヘキシレングリコール溶液から種々の結晶化条件で結晶化して得た試料に含まれるα型およびγ型結晶の混在率をX線法により求め, その結果を検討した. ヘキシレングリコール溶液から0および100℃で結晶化した試料にはγ型結晶の存在は認められなかった. 以下に述べる結果はグリセリン溶液から結晶化して得た試料についてである. 等温結晶化温度が高くなるとともにγ型結晶の混在率が減少する. 140℃でこの減少が大きく, 160℃では主としてα型結晶が生成している. 等温結晶化温度140℃では結晶化時間とともにγ型結晶の混在率が減少し, 100℃では反対に増加する. しかし100℃では140℃に比べより短い時間で混在率がほぼ一定となる. 等温結晶化温度100℃では溶液濃度の増加とともにγ型結晶の混在率が減少する. 結晶化温度が100℃以上の試料を200℃で10時間減圧中で熱処理した試料のγ型結晶の混在率は未処理のそれに比べるとほぼ同じか少し増加している程度である. しかし0℃で結晶化した試料はこの熱処理によりγ型の混在率が大きく減少している.
9 citations
TL;DR: In this paper, a thermistor anemometer is described for measuring low air velocities of 0.100 cm/sec, which is a measurement of air flow direction.
Abstract: A new thermistor anemometer is described for measuring low air velocities of 0–100 cm/sec. A theoretical performance curve (anemometer output vs air velocity) was calculated for the instrument. When compared with the experimental performance data, good correlation existed. Several characteristics of the anemometer were investigated experimentally. The instrument displayed excellent sensitivity and good stability (reproducibility of the calibration curve at a given ambient temperature). The output was not affected by the air flow direction. The anemometer output was affected by changes in ambient temperature, and the use of calibration curves for various ambient temperatures is suggested.
TL;DR: A linear equation which relates drum screw scale to arcsin(N sinø) for the prism spectrometer calibration has been developed and allows the preparation of a calibration table of numbers, rather than the usual less precise drum-wavelength calibration curve, for practical transfer of wavelength drum-scale values D to wavelengths lambda.
Abstract: Based on the minimum deviation equation N
sinϕ = sin(ϕ
+ δ), a linear equation which relates drum
screw scale to arcsin(N sinϕ) for the
prism spectrometer calibration has been developed. The use of this linear
equation and the dispersion formula for prism material allows the preparation of
a calibration table of numbers, rather than the usual less precise
drum-wavelength calibration curve, for practical transfer of wavelength
drum-scale values D to wavelengths λ. The method
requires only two or three reference points, applicable to various prisms with
high accuracy in their recommended wavelength range. The linearity suggests
another advantage, because it permits linear transformation of the old drum
setting for a prism that was first calibrated to the new drum setting.
01 Apr 1971
TL;DR: In this paper, a polybutadiene sample prepared by a-methylstyrene tetramer-Na2 initiation was chromatographed using dual detection, consisting of a differential refractometer, and an ultraviolet absorption spectrophotometer.
Abstract: The calibration of gel permeation chromatograph (GPC) for a given polymer type is usually done by running well-characterized polymer samples of the same type. The available polystyrene and polyglycol standards with molecular weights below 5000 do not give parallel calibration curves, and the points for polystyrene are not on an extension of the higher-molecular-weight portion of the curve. In order to check the calibration in this low molecular-weight region and to establish an independent curve for polybutadiene, a polybutadiene sample prepared by a-methylstyrene tetramer-Na2 initiation was chromatographed. In doing this, dual detection was used, consisting of a differential refractometer, and an ultraviolet absorption spectrophotometer. The UV signal from the spectrophotometer was assumed to represent the tetramer portion of the polymer, and its percentage was calculated at each volume increment, using externally determined response factors. This percentage and the tetramer molecular weight giv...
TL;DR: In this paper, the diameters of aqueous NaCl solution aerosols generated by atomization were determined with the aid of the calibration curve between the spot and droplet diameters.
Abstract: Droplets of aqueous NaCl solution aerosols generated by atomization were collected on an AgNO3 containing film, by measuring microscopically the sizes of the AgCl spots formed on the film, the diameters of the droplets were determined with the aid of the calibration curve between the spot and droplet diameters It was found that the calibration curve can be expressed by a relation Dd3=Kds2, where Dd is the volume average diameter of the droplets, ds the surface average diameter of the spots and K a constant The meaning of K was considered
TL;DR: Theoretical calibration curves for the subsurface gamma-scatter density probe are derived in this article, based on solution of the one-dimensional transport equation implemented by generally available computer programs, DTF IV and GAMLEG.
TL;DR: In this paper, the choice of a calibration curve to study transformation of polymers is discussed, as well as the reasons for adopting the Moore calibration curve relating size of polymer to elution volume and problems associated with changes in the distribution of a polymer during a reaction are examined.
TL;DR: In this article, a combustion method for the determination of sulphur in copper is proposed, where the sample is heated at 1150° in a stream of air; the evolved gas is passed into a solution of sodium tetrachloromercurate, and the product is reacted with p-rosaniline hydrochloride and formaldehyde to form a purple sulphonic acid derivative ofp-rosanoline, which is measured spectrophotometrically.
TL;DR: In this paper, a variable take-off geometry was proposed for X-ray fluorescence analysis without calibration curves or the knowledge of the primary Xray spectrum, which can be regarded as an absolute method.
Abstract: Two years ago a paper (1) on a new method of X-ray fluorescence analysis was presented. This method uses a variable take-off geometry and permits a quantitative analysis without calibration curves or the knowledge of the primary X-ray spectrum(2). As references either chemically analysed samples or pure elements are used. In case that only primary excitation exists, under the aspect mentioned above, the method is to be regarded as “absolute”. For secondary excitation a simple parabolic approximation has been introduced, which requires a calibration. This paper gives an outline on the progress obtained during the last two years.
TL;DR: In this article, a method for the calibration of an online density meter is presented, along with a bound on the error of prediction that accounts for various sources of random error, and a worked example illustrates how to calibrate a density meter.
Abstract: This paper presents a method for the calibration of an on-line density meter. Formulae for the prediction of density are given along with a bound on the error of prediction that accounts for various sources of random error. A worked example illustrates ..
TL;DR: In this paper, the linear relationships obtained for, copper, bismuth, and cadmium in high purity silver to 0.1 ppm are shown. But the linear relationship was not applied to high purity gold.
Abstract: When a dc arc is used for trace analysis on a spectrometer, calibration curves with a pronounced toe due to spectral background are found. For analysis of high purity materials it is most important that linear relationships should be established to ultra-trace levels when total impurity content is specified within the ppm level. A solution to this problem is outlined and the linear relationships obtained for, copper, bismuth, and cadmium in high purity silver to 0.1 ppm are shown. An electronic circuit is described that enables these background corrections to be made.
TL;DR: A pressure transducer, consisting of a peizojunction sensing element, has been developed for meauring both static and transient pressures as mentioned in this paper, and the calibration curve showed a ±1.5% FSO (full scale output) independent linearity, a 3% fSO hysteresis, and a repeatability of 0.5%.
Abstract: A pressure transducer, consisting of a peizojunction sensing element, has been developed for meauring both static and transient pressures. In the static mode of operation the calibration curve showed a ±1.5% FSO (full scale output) independent linearity, a 3% FSO hysteresis, and a repeatability of 0.5% FSO. Dynamically, the transducer exhibited a thermal sensitivity shift of 0.27% FSO/°C.
01 Jan 1971
TL;DR: A comparison of the two efficiencies produced for each sample is made to diagnose instrument drift, contamination, misprinting, inhomogeneity and other miscellaneous errors.
Abstract: A three channel liquid scintillation counting system is described in which quench-corrections are derived simultaneously from both sample and external standard channels ratio procedure for each sample. Calibration curves are modelled by a series of quadratic regressions using a Fortran program run on an Elliott 905 computer. Sample data are processed by a second Fortran program. A comparison of the two efficiencies produced for each sample is made to diagnose instrument drift, contamination, misprinting, inhomogeneity and other miscellaneous errors.
TL;DR: A number of reactions have been used to obtain the single γ-raY spectra to obtain shape calibration curve and peak-to-total ratio for a 5″ × 6″ NaI(Tl) scintillation detector from 0.662 to 8.92 MeV of energy as mentioned in this paper.
TL;DR: In this paper, the authors determined the total aromatic content in lubricating oil stocks by infrared absorption method and found that there are linear correlation between molecular weight of samples and gradient of their calibration curves.
Abstract: Determination of total aromatic content in lubricating oil stocks by infrared absorption method was investigated. The following conclusions were obtained from the experimental results.1) Four representative lubricating oil stocks A, B, C and D were separated into two main components, saturated hydrocarbons and aromatic hydrocarbons respectively by silica gel adsorption chromatography. Standard samples containing 1050wt% aromatics were prepared by adding aromatic hydrocarbons to saturated hydrocarbons obtained in chromatography.Linear calibration curves were obtained from the aromatic contents and the infrared absorbances at near 1, 613cm-1 of standard samples. And also, it was found that there are linear correlation between molecular weight of samples and gradient of their calibration curves.2) Total aromatic contents in various lubricating oil stocks produced at the refinery in this country and foreign country from same crude oil were determined by chromatographic method and infrared absorption method. As a result, analytical values from these method agreeded with one another within ±3% by relative error.3) As this procedure is simple and rapid (10min/one sample), this is considered as a very useful method for routine analysis.