A Computerised Least-Square Method for the Determination of Association Constant and Molar Absorptivity of 1: 1 Molecular Complexes from Spectrophotometry Data

1984 ◽  
Vol 265O (1) ◽  
Author(s):  
B. K. Seal ◽  
A. K. Mukherjee ◽  
D. C. Mukherjee
Keyword(s):  
Association Constant ◽  
Molecular Complexes ◽  
Least Square Method ◽  
Molar Absorptivity ◽  
Least Square

X-ray Diffractometric Determination of Lattice Misfit Between γ and γ' Phases in Ni-Base Superalloys

1988 ◽  
Vol 32 ◽  
pp. 365-375 ◽  
Author(s):  
Katsumi Ohno ◽  
Hirosi Harada ◽  
Toshihiro Yamagata ◽  
Michio Yamazaki ◽  
Kazumasa Ohsumi
Keyword(s):  
Lattice Misfit ◽  
Least Square Method ◽  
Least Square ◽  
X Rays ◽  
Deconvolution Method ◽  
X Ray ◽  
Window Functions ◽  
Profile Fitting ◽  
Overlapping Peaks

AbstractThe lattice misfits between γ and γ' phases in Ni-base superalloys (single crystal) were accurately determined for filings of specimens by using both a conventional X-ray tube focusing diffractometer(CXRFD) and a synchrotron-radiation parallel beam X-ray diffractometer (SRPXRD). All reflection peaks measured with the CXRFD were in a cluster of overlapping peaks because of the very small differences in the lattice parameters of both phases and the instrumental broadening due to X-ray optics including the spectral distribution of Xray source such as CuKα doublet. The deconvolution method was applied to remove the instrumental broadening from the peaks measured with the CXRFD. The window functions for the deconvolution method were calculated from CuKα doublet reflection of Si standard by a nonlinear least-square method.The instrumental broadening of SRPXRD was much smaller than that of CXRFD since the monochromatic X-rays produced single peak profiles and constant profile shape over a wide 2θ range. A profile fitting with a pseudo-Voigt function was used to determine 2θ angles to 0.0005 deg. for the synchrotron powder data. The peak angle and shape reflected from γ' phases in γ-matrix and those fron electrochemically extracted γ'-phase were significantly different.

scholarly journals Numerical evaluation of the modulus of longitudinal elasticity in structural round timber elements of the Eucalyptus genus

2011 ◽  
Vol 31 (5) ◽  
pp. 1007-1014 ◽  
Author(s):  
André L. Christoforo ◽  
Túlio H. Panzera ◽  
Fabiano B. Batista ◽  
Paulo H. R. Borges ◽  
Francisco A. R. Lahr
Keyword(s):  
Inverse Analysis ◽  
Numerical Evaluation ◽  
Least Square Method ◽  
Least Square ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Eucalyptus Citriodora ◽  
Inverse Analysis Method ◽  
Round Timber

Currently, the standards that deal with the determination of the properties of rigidity and strength for structural round timber elements do not take in consideration in their calculations and mathematical models the influence of the existing irregularities in the geometry of these elements. This study has as objective to determine the effective value of the modulus of longitudinal elasticity for structural round timber pieces of the Eucalyptus citriodora genus by a technique of optimization allied to the Inverse Analysis Method, to the Finite Element Method and the Least Square Method.

scholarly journals Determination of the Sediment Carrying Capacity Based on Perturbed Theory

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Zhi-hui Ni ◽  
Qiang Zeng ◽  
Wu Li-chun
Keyword(s):  
Carrying Capacity ◽  
Influencing Factor ◽  
Least Square Method ◽  
Least Square ◽  
New Method ◽  
Linear Regression Method ◽  
Average Flow Velocity ◽  
New Formula ◽  
Sediment Carrying Capacity

According to the previous studies of sediment carrying capacity, a new method of sediment carrying capacity on perturbed theory was proposed. By taking into account the average water depth, average flow velocity, settling velocity, and other influencing factors and introducing the median grain size as one main influencing factor in deriving the new formula, we established a new sediment carrying capacity formula. The coefficients were determined by the principle of dimensional analysis, multiple linear regression method, and the least square method. After that, the new formula was verified through measuring data of natural rivers and flume tests and comparing the verified results calculated by Cao Formula, Zhang Formula, Li Formula, Engelung-Hansen Formula, Ackers-White Formula, and Yang Formula. According to the compared results, it can be seen that the new method is of high accuracy. It could be a useful reference for the determination of sediment carrying capacity.

scholarly journals A linear regression approach in the determination of work standards for a manufacturing organisation

2007 ◽  
Vol 25 (1) ◽  
pp. 30
Author(s):  
S.A. Oke
Keyword(s):  
Linear Regression ◽  
Least Square Method ◽  
Least Square ◽  
Manufacturing Plants ◽  
Scientific Investigations ◽  
Manufacturing Operations ◽  
Penalty Costs ◽  
Production Manager ◽  
Established Technique

In semi-automated roofing sheets manufacturing plants, production managers receive large orders, which most often, are to be delivered within scheduled delivery dates; failure to deliver orders incurs penalty costs and litigation charges. The challenge therefore for the production manager is to be able to predict product completion period and map available labour man-hours to production of roofing sheet orders. This paper presents a linear regression model for setting up work standards for a roofing sheet manufacturing plant. Linear regression is a relatively established technique in scientific investigations, but new in its applied form to work standards, particularly in roofing sheets manufacturing operations standards setting. The accuracy of the model was determined by the least square method, and the result suggests the feasibility of applying a model in the case presented. Thus, the contribution of this paper lies in the application of a known technique in a new area. The utility of the tool is in its ability to provide useful information for production planning and implementation purposes in the roofing sheets plants.

scholarly journals Determination of chromium (VI) in the dust of gas treatment plants in steelmaking plants.

2020 ◽  
pp. 42-44
Author(s):  
V. A. Makarov ◽  
T. K. Savosteenko
Keyword(s):  
Hexavalent Chromium ◽  
Raw Materials ◽  
Potassium Dichromate ◽  
Least Square Method ◽  
Photometric Determination ◽  
Least Square ◽  
Photometric Method ◽  
Gas Treatment ◽  
Gas Cleaning

The requirements for the content of hexavalent chromium in cements and raw materials for its manufacture are described. The problem with the utilization of dust from gas treatment plants of metallurgical plants at metallurgical enterprises is given. The influence of the chemical composition of the dust of gas cleaning plants of metallurgical plants on the determination of hexavalent chromium is established. A method for measuring the hexavalent chromium in the dust of gas cleaning plants of metallurgical plants by the photometric method is described. A method has been developed for extracting hexavalent chromium from dust at the cleaning units of metallurgical plants for subsequent photometric determination. An extraction method has been established to prevent underestimation of the hexavalent chromium content. The determination of hexavalent chromium was based on the formation of a blue-violet complex with diphenylcarbazide. Calibration was carried out on aque solutions with a known concentration of hexavalent chromium. For the preparation of calibration solutions, potassium dichromate of chemical purity was used. The concentration of hexavalent chromium in each calibration solution was carried out by a calculation method, overlapping the entire measurement range. The measurement of optical density was carried out on a photoelectric colorimeter type KFK-3, at a wavelength of 540 nm. Analysis of the obtained calibration dependence showed a good correlation. The calibration factor was calculated using the least square method. Extraction of hexavalent chromium from the sample to be analyzed was performed with water. The reducing effect of iron was eliminated with a solution of phosphoric acid. The developed technique is used when conducting certification control of dust from gas cleaning units of metallurgical plants, as well as during research.A validation procedure was carried out. Obtained acceptable limits of repeatability and reproducibility of the method.

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