On Li-bearing micas: estimating Li from electron microprobe analyses and an improved diagram for graphical representation

1997 ◽  
Vol 61 (409) ◽  
pp. 809-834 ◽  
Author(s):  
Gerhard Tischendorf ◽  
Bärbel Gottesmann ◽  
Hans-Jürgen Förster ◽  
Robert B. Trumbull
Keyword(s):  
Electron Microprobe ◽  
Graphical Representation ◽  
Site Occupancy ◽  
Essential Element ◽  
Regression Equations ◽  
Two Dimensional ◽  
Octahedral Layer ◽  
Empirical Relationships ◽  
Free Mica ◽  
Scientific Rationale

AbstractLithium may constitute an essential element in micas, yet it cannot be detected by the electron microprobe. Since Li is critical for correctly classifying micas and properly calculating their formulae, several methods have been proposed to overcome this analytical deficiency. We offer empirical relationships between Li2O and SiO2, MgO, F, and Rb in trioctahedral micas, and between Li2O and F as well as Rb in dioctahedral micas. The resultant regression equations enable lithium contents to be sufficiently well estimated from EPM analyses within the range of validity discussed.Secondly, we introduce an easy to handle, new diagram with the axis variables [Mg-Li] and [Fetot + Mn + Ti-AlVI] for graphical representation and discuss its scientific rationale. Being based on absolute abundances of cations in the octahedral layer, the diagram provides a simple means to classify micas in terms of composition and octahedral site occupancy, and it also allows compositional relationships between Li-bearing and Li-free mica varieties as well as between trioctahedral and dioctahedral micas to be displayed on a single, two-dimensional diagram.

The chemistry and cell parameters of omphacites and related pyroxenes

1969 ◽  
Vol 37 (285) ◽  
pp. 61-74 ◽  
Author(s):  
A. D. Edgar ◽  
A. Mottana ◽  
N. D. Macrae
Keyword(s):  
Powder Diffraction ◽  
Electron Microprobe ◽  
Graphical Representation ◽  
Chemical Compositions ◽  
Chemical Analyses ◽  
X Ray ◽  
Cell Parameters ◽  
Cell Dimensions ◽  
Approximate Estimation

SummaryIn an attempt to correlate the chemical compositions and cell sizes of omphacites and related pyroxenes, the cell dimensions of fifty-five analysed pyroxenes have been determined, or taken from the literature. Twenty-two of the chemical analyses are new, nineteen of them being done by electron microprobe. Approximately two-thirds of the total number of analyses may be considered first class, the remainder are of doubtful or unknown quality. Cell parameters, determined by X-ray powder diffraction methods, have errors of 0·1 % for the majority of samples, although for some samples taken from the literature errors are unknown.The majority of methods of recalculating omphacite analyses into their end-member molecules are unsuitable for correlation of cell constants with chemistry, mainly due to the impossibility of graphical representation of more than three end-member molecules, and to the non-stoichiometry of these molecules. Using a modification of Tröger's (1962) method of recalculating chloromelanite analyses the present analyses have been recalculated into the diopside-jadeite-acmite and diopside-jadeite-hedenbergite molecules and compared with their determined cell parameters. Because of the gradations in all parameters between these end-member molecules, determination of compositions based on the cell parameters (a, b, c, vol, or β) can only be made within wide limits. However, using a method of projection of compositions from the acmite and hedenbergite apices to the diopside-jadeite join the ratios of diopside to jadeite can be determined for most samples to within ±5 mol%. As there are the most important constituents of most omphacites, this method permits an approximate estimation of omphacite compositions. From a knowledge of the cell sizes of the omphacite a rough indication of the conditions of formation of its host rock may also be obtained.

scholarly journals Simultaneous spectrophotometric determination of drugs lacking peak maxima in their zero-order profiles by graphical or statistical representation of data

2018 ◽  
Vol 9 (3) ◽  
pp. 194-201
Author(s):  
Ragaa Magdy ◽  
Ahmed Hemdan ◽  
Nermine Victor Fares ◽  
Maha Farouk
Keyword(s):  
Graphical Representation ◽  
Reference Method ◽  
Zero Order ◽  
Regression Equations ◽  
Spectrophotometric Methods ◽  
Statistical Representation ◽  
Tablet Dosage ◽  
Direct Spectrophotometry ◽  
One Way Anova

Trandolapril has no sharp peak in its zero-order spectrum, therefore it is difficult to be measured by direct spectrophotometry. In this study, direct univariate spectrophotometric methods were developed and validated for determination of Trandolapril and Verapamil combination in pure and tablet dosage forms. The first method for measuring both Trandolapril and Verapamil is Absorbance Subtraction (AS), this method depends on the presence of iso-absorptive point in the zero-order curve at 217 nm. It has the advantage of measuring the concentration of both Trandolapril and Verapamil from unified regression equation at the iso-absorptive point. The second, third and fourth methods were applied on the first order spectra of the studied drugs. Second method is Derivative Subtraction (DS) for Trandolapril and Derivative subtraction followed by spectrum subtraction (DS-SS) for Verapamil. The third and fourth methods are constant value and concentration value methods. In the concentration value method, the concentration of the drugs is determined from the graphical representation without the use of regression equations. All the developed methods were validated as per International Conference on Harmonization guidelines and the results proved that the developed methods are simple, accurate, and selective. Moreover, a statistical comparison between the developed methods and a reference method was done. Also, One-way ANOVA statistical test was done between all the proposed spectrophoto-metric methods and results showed no significant differences.

scholarly journals IMAGES CONVERTER OF GEOLOGIC- LITHOLOGICAL PROFILES

2021 ◽  
Vol 445 (1) ◽  
pp. 121-126
Author(s):  
D. B. Nurseitov ◽  
N. A. Toiganbayeva ◽  
M. O. Kenzhebayeva
Keyword(s):  
Image Segmentation ◽  
Distribution Density ◽  
Graphical Representation ◽  
Oil Field ◽  
Object Oriented Programming ◽  
Two Dimensional ◽  
Dimensional Array ◽  
Digital Format ◽  
The Matrix ◽  
Oriented Programming Language

The article is devoted to the program "Converter", which allows you to translate the geologic-lithological profile of a mineral field into a digital format in the form of a two-dimensional array. The object-oriented programming language Python was used to write the program. The NumPy, OpenCV, and MatPlotlib libraries are actively used. The implementation of this program is based on image segmentation and finding the prevailing colors in the OpenCV library. Image segmentation is a preliminary step in image processing. The obtained values allow you to find out the density distribution in the area under consideration. The program "Converter" has a good graphical representation of the results obtained using the MatPlotlib library. The program writes the final converted result as a two-dimensional array to a text file along the desired path. Thus, the matrix is easy to read for further use in conjunction with other programs. The purpose of this work was to create a program that converts the geologic-lithological profile of the field into a digital format in the form of a two-dimensional array, for further use of this matrix as the distribution density of the oil field. The "Converter" program converts any geologic-lithological profile into a two-dimensional array in a matter of minutes.

scholarly journals Crystal structure of bis(acetylacetonato-κ2O,O′)(tetrahydrofuran-κO)(trifluoromethanesulfonato-κO)iron(III)

2015 ◽  
Vol 71 (10) ◽  
pp. 1165-1168
Author(s):  
Casseday P. Richers ◽  
Jeffery A. Bertke ◽  
Thomas B. Rauchfuss
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Site Occupancy ◽  
Title Complex ◽  
Two Dimensional ◽  
Hydrogen Bonding Interactions ◽  
Octahedral Environment ◽  
Distorted Octahedral ◽  
Length Range ◽  
A Site

The mononuclear title complex, [Fe(CF3O3S)(C5H7O2)2(C4H8O)] or [Fe(acac)2(OTf)(THF)] (acac = acetylacetonate; OTf = trifluoromethanesulfonate; THF = tetrahydrofuran), (I), consists of one six-coordinate Fe3+atom in a slightly distorted octahedral environment [Fe—O bond-length range = 1.9517 (11)–2.0781 (11) Å]. The triflate ligand was found to be disordered over two sets of sites, with a site-occupancy ratio of 0.622 (16):0.378 (16). Weak intermolecular C—H...O and C—H...F hydrogen-bonding interactions generate a two-dimensional supramolecular structure lying parallel to (100). This is only the second crystal structure reported of a mononuclear bis(acetylacetonato)iron(III) complex.

A graphical depiction of multivariate similarity among sample plots

1988 ◽  
Vol 18 (4) ◽  
pp. 467-472 ◽  
Author(s):  
N. J. Smith ◽  
K. Iles
Keyword(s):  
Multidimensional Scaling ◽  
Rank Order ◽  
Basal Area ◽  
Site Index ◽  
Regression Equations ◽  
Two Dimensional ◽  
Measure Of Similarity

A system for graphically comparing multivariate similarity between a large number of sample plots is presented. Two-dimensional nonmetric (rank order) multidimensional scaling is used to generate maps. These maps display either stand variables (site index, basal area, normality (used as a measure of stocking), change in normality, age and stems per hectare), or three site variables (aspect, elevation, and latitude). The distance between any two points (representing a plot) on these maps is the measure of similarity. Regression equations are used to predict additional map locations.

Three-Dimensional Scour Below Pipelines

1988 ◽  
Vol 110 (4) ◽  
pp. 373-379 ◽  
Author(s):  
J. Fredso̸e ◽  
E. A. Hansen ◽  
Y. Mao ◽  
B. M. Sumer
Keyword(s):  
Three Dimensional ◽  
Essential Element ◽  
Laboratory Model ◽  
Span Length ◽  
Two Dimensional ◽  
Practical Application ◽  
Field Situation ◽  
Scour Holes ◽  
The Individual ◽  
A Current

This paper deals with the scour below pipelines exposed to a current. In a typical field situation, the scour pattern along a pipeline is not uniform; the scour holes are interrupted with the reaches where the pipeline is partially or totally buried. This paper focuses on the longitudinal extent of the individual scour holes. A simplified picture of the process is given to describe the longitudinal dimension of a scour hole. The sagging of the pipeline is an essential element of the process. The effect of sagging on the final scour depth is investigated, using a two-dimensional laboratory model. A simple equation to calculate the length of individual scour holes (the span length) is developed. The practical application of the equation is demonstrated by an example.

New Concepts on Two-Dimensional Data Visualization With Applications in Engineering Analysis and Design

2012 ◽  
Vol 12 (2) ◽  
Author(s):  
P. A. Simionescu ◽  
Mehrube Mehrubeoglu
Keyword(s):  
Graphical Representation ◽  
Damping Ratio ◽  
Two Dimensional ◽  
Engineering Analysis ◽  
Science And Engineering ◽  
Single Degree Of Freedom ◽  
Analysis And Design ◽  
New Concepts ◽  
New Ideas ◽  
Detailed Application

The use of information visualization in engineering analysis and design has increased exponentially, making it indispensable in science and engineering education. In this paper, several new concepts on graphical representation of two-dimensional data are presented, and their implementation in a computer program called D_2D detailed. Application examples include mechanism kinematics, vibrations, and optimizations. New ideas on plotting inequalities of two variables, damping ratio evaluation of single degree-of-freedom vibratory systems, and time ratio calculation of crank-driven mechanisms are presented in paper.

scholarly journals THE BIPLOT DISPLAY OF THE TALL FESCUE TURF VARIETY TRIAL DATA

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1173e-1173
Author(s):  
George C.J. Fernandez
Keyword(s):  
Tall Fescue ◽  
Graphical Representation ◽  
Trial Data ◽  
Data Matrix ◽  
Two Dimensional ◽  
Multivariate Technique ◽  
Variety Trial ◽  
Quality Ratings ◽  
Regression Techniques ◽  
The Common

Tire interpretation of variety trials conducted with many genotypes (G) grown in many environments (E) is usually complicated by the presence of the significant G × E interaction. The common statistical analysis using ANOVA and linear regression techniques are often inadequate to study the complex two-way data structure. The biplot, a multivariate technique provides, a graphical representation of the interaction, which allows the response of each G in each E to be displayed in a two dimensional plot. It displays not only the configuration of G and E, but it also relates the two. The importance of biplot display is illustrated by using the tall fescue variety trial data on mean quality ratings published by the National Turfgrass Evacuation Program. The biplot displays about 60% of the information in the 24 (G) × 23 (E) data matrix. Environments TX3 and GA1 responded differently from other environments. Based on the biplot display genotypes are grouped and their significance will be discussed.

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