Calculation of the temperature of crystallization of silicates from basaltic melts

1981 ◽  
Vol 44 (333) ◽  
pp. 19-26 ◽  
Author(s):  
W. J. French ◽  
E. P. Cameron
Keyword(s):  
Crystallization Temperature ◽  
Maximum Error ◽  
Average Error ◽  
Multivariate Statistical Techniques ◽  
Multivariate Statistical ◽  
Marquesas Islands ◽  
Melt Composition ◽  
The Relationship ◽  
Basaltic Melts

AbstractThis paper discusses the relationship between the chemical composition of basic melts and the temperatures at which olivine, clinopyroxene, and plagioclase begin to crystallize at one atmosphere. Diagrams are given which show the correlation between crystallization temperature and melt composition and which allow some of the temperatures to be estimated. Because the relationship between melt composition and crystallization temperature is virtually linear over short compositional ranges, the data available can be subdivided and examined by linear multivariate statistical techniques. The result is a set of equations which permit the crystallization temperatures to be calculated with an average error of less than 6 °C and a maximum error of 27 °C. These equations have been tested by experimental determination of crystallization temperatures for a range of rocks from the Marquesas Islands.

Motoric Indicators of Laterality and Determination of Lateral Dominance in Schizophrenia

1985 ◽  
Vol 60 (3) ◽  
pp. 971-985 ◽  
Author(s):  
David G. Scott
Keyword(s):  
Psychiatric Inpatient ◽  
Statistical Techniques ◽  
Behavioral Characteristics ◽  
Complex Phenomenon ◽  
Multivariate Statistical Techniques ◽  
Multivariate Statistical ◽  
Cerebral Laterality ◽  
Lateral Dominance ◽  
Normal Controls

The literature suggests that schizophrenics exhibit reduced or reversed cerebral lateral dominance relative to normal control subjects. An hypothesis which predicted reduced or reversed cerebral laterality for schizophrenics was tested on 60 young, familially right-handed males, with 20 men in each of the following three groups: schizophrenic inpatients, nonschizophrenic psychiatric inpatient controls, and normal controls. The subjects were administered a battery of seven measures of cerebral laterality. The application of multivariate statistical techniques showed groups did not differ significantly in the degree or the direction of their cerebral lateral dominance. Also there were no significant correlations between the measures of laterality. The findings suggest that cerebral lateral dominance is not necessarily altered concomitantly with psychopathology but rather that it is a complex phenomenon which may not be reliably determined on the basis of simple behavioral characteristics.

A new simple absolute viscometer for use in experimental systems with limited access to the liquid

1968 ◽  
Vol 46 (12) ◽  
pp. 1969-1976 ◽  
Author(s):  
M. K. Nagarajan
Keyword(s):  
Solid Sphere ◽  
Pressure Vessels ◽  
Average Error ◽  
Exact Equation ◽  
Vacuum Chambers ◽  
Experimental Systems ◽  
Solid Gold ◽  
Absolute Viscosity ◽  
The Relationship

A novel type of vertically oscillating bob viscometer for liquids is described. The mathematical theory of a solid sphere oscillating in a viscous liquid is developed, and results in an exact equation depicting the relationship between the logarithmic decrement of the oscillations of the sphere and the viscosity of the liquid surrounding the bob. The use of this technique for the determination of absolute viscosity of liquids is demonstrated. Using five sample liquids, at room temperature, the average error between the absolute viscosities determined and those of previous measurements is ± 1.5%.The viscometer consists of a quartz spring, which suspends a solid gold sphere, hanging vertically. The oscillations of the system are sensed by electrically recording the output of a linear variable differential transformer, the core of which forms a part of the oscillating system. The oscillations are stimulated electrically; the positioning of the transducer core is precisely adjustable with the use of an electric motor driven mechanism. Thus, the viscometer can be entirely remotely controlled and is, therefore, recommended for experimental situations which make the liquid not easily accessible, e.g. inside furnaces, pressure vessels, vacuum chambers, etc.

scholarly journals Determining Some Factors of the Financial Situation in the European Union Publishing Sector

2018 ◽  
Vol 18 (1) ◽  
pp. 25-43
Author(s):  
José Ángel Sanz ◽  
Ana María Bedate ◽  
Mariano Durántez
Keyword(s):  
European Union ◽  
Cultural Industries ◽  
The European Union ◽  
Multivariate Statistical Techniques ◽  
Cultural Industry ◽  
Multivariate Statistical ◽  
Number Of Factors ◽  
Synthetic Indicator ◽  
Financial Profile ◽  
The Relationship

Abstract The publishing sector is probably a cultural industry with one of the greatest economic projections due to its huge turnover and contribution to the Gross Domestic Product of countries. In order to gain a better understanding of this sector, this paper examines a sample of the most important companies belonging to this sector in the European Union, focusing on studying their economic-financial profile. In order to achieve this, multivariate statistical techniques are used to create indicators on the evolution of the main variables and financial ratios of these companies over recent years. The specific objectives are: to summarise the information in a smaller number of factors, which in turn enable us to construct a robust and reliable synthetic indicator; and investigate the relationship between the constructed index and different variables such as company age, size and localisation. The changes experienced in this sector are reflected in the obtained results and provide a richer understanding of cultural industries.

New Magmatic Oxybarometer Using Trace Elements in Zircon

2020 ◽  
Vol 61 (3) ◽  
Author(s):  
Robert R Loucks ◽  
Marco L Fiorentini ◽  
Gonzalo J Henríquez
Keyword(s):  
Standard Error ◽  
Crystallization Temperature ◽  
Natural Populations ◽  
Silicate Melt ◽  
Similar Degree ◽  
Magmatic Differentiation ◽  
Ionic Charge ◽  
Zircon Thermometry ◽  
Melt Composition

Abstract We derive a novel method for determining the oxidation state of a magma as zircon crystallized, with a standard error of ±0·6 log unit ƒO2, using ratios of Ce, U, and Ti in zircon, without explicit determination of the ionic charge of any of them, and without independent determination of crystallization temperature or pressure or parental melt composition. It yields results in good agreement with oxybarometry on Fe–Ti oxide phenocrysts and hornblende phenocrysts quenched in eruptive I- and A-type dacites and rhyolites, but our zircon oxybarometer is also applicable to slowly cooled plutonic rocks and applicable to detrital and xenocrystic zircons. Zircon/melt partition coefficients of Ce and U vary oppositely with ƒO2 variation in the silicate melt. The Ce/U ratio in zircon also varies with the Ce/U element ratio in the silicate melt. During mafic-to-felsic magmatic differentiation, Ce and U are incorporated mainly in calcium-dominated lattice sites of clinopyroxene, hornblende, apatite, and occasionally titanite and/or allanite, all of which have a similar degree of preference for Ce over U. We employ the U/Ti ratio in zircon and in silicate melt as a magmatic differentiation index. Convergent- and divergent-plate-margin differentiation series consistently follow the relation log (Ce/U) ≈ –0·5 log (U/Ti) + C' in silicate melts of basaltic to rhyolitic composition. That correlation permits thermodynamic derivation of the oxybarometry relation among those elements in zircon: log fO2(sample)−log fO2(FMQ)≈42n+1log[Ce/(Ui×Ti)z]+C, wherein Ui denotes age-corrected initial U content, FMQ represents the reference buffer fayalite + magnetite + quartz, superscript z denotes zircon, and n varies with the average valence of uranium in the zircon’s parental silicate melt. We empirically calibrate this relation, using 1042 analysed zircons in 85 natural populations having independently constrained log ƒO2 in the range FMQ – 4·9 to FMQ + 2·9, to obtain the equation log fO2(sample)−log fO2(FMQ)=3·998(±0·124) log[Ce/(Ui×Ti)z]+2·284(±0·101) with a correlation coefficient R = 0·963 and standard error of 0·6 log unit ƒO2 in calc-alkalic, tholeiitic, adakitic, and shoshonitic, metaluminous to mildly peraluminous and mildly peralkaline melts in the composition range from kimberlite to rhyolite. Thermodynamic assessment and empirical tests indicate that our formulation is insensitive to varying crystallization temperature and pressure at lithospheric conditions. We present a revised equation for Ti-in-zircon thermometry that accounts appropriately for pressure as well as reduced activity of TiO2 and SiO2 in rutile- and quartz-undersaturated melts. It can be used to retrieve absolute values of ƒO2 from values of ΔFMQ obtained from a zircon analysis.

Thromboplastin Related Differences in the Determination of International Normalised Ratio: A Cause for Concern?

1994 ◽  
Vol 72 (03) ◽  
pp. 426-429 ◽  
Author(s):  
S Kitchen ◽  
I D Walker ◽  
T A L Woods ◽  
F E Preston
Keyword(s):  
Patient Management ◽  
External Quality Assessment ◽  
Oral Anticoagulant Therapy ◽  
Warfarin Dosage ◽  
External Quality ◽  
External Quality Assessment Scheme ◽  
International Normalised Ratio ◽  
The Uk ◽  
The Relationship

SummaryWhen the International Normalised Ratio (INR) is used for control of oral anticoagulant therapy the same result should be obtained irrespective of the laboratory reagent used. However, in the UK National External Quality Assessment Scheme (NEQAS) for Blood Coagulation INRs determined using different reagents have been significantly different.For 18 NEQAS samples Manchester Reagent (MR) was associated with significantly lower INRs than those obtained using Diagen Activated (DA, p = 0.0004) or Instrumentation Laboratory PT-Fib HS (IL, p = 0.0001). Mean INRs for this group were 3.15, 3.61, and 3.65 for MR, DA, and IL respectively. For 61 fresh samples from warfarin-ised patients with INRs of greater than 3.0 the relationship between thromboplastins in respect of INR was similar to that observed for NEQAS data. Thus INRs obtained with MR were significantly lower than with DA or IL (p <0.0001). Mean INRs for this group were 4.01, 4.40, and 4.59 for MR, DA, and IL respectively.We conclude that the differences between INRs measured with the thromboplastins studied here are sufficiently great to influence patient management through warfarin dosage schedules, particularly in the upper therapeutic range of INR. There is clearly a need to address the issues responsible for the observed discrepancies.

LIQUIDUS THERMO-BAROMETER FOR THE MODELING OF MAGNETITE — MELT EQUILIBRIUM

2018 ◽  
pp. 71-80
Author(s):  
N. S. Aryaeva ◽  
E. V. Koptev-Dvornikov ◽  
D. A. Bychkov
Keyword(s):  
Experimental Data ◽  
Liquidus Temperature ◽  
Vertical Structure ◽  
Maximum Error ◽  
Silicate Melt ◽  
System Of Equations ◽  
Wide Range ◽  
Basaltic Melts ◽  
Multidimensional Statistics

A system of equations of thermobarometer for magnetite-silicate melt equilibrium was obtained by method of multidimensional statistics of 93 experimental data of a magnetite solubility in basaltic melts. Equations reproduce experimental data in a wide range of basalt compositions, temperatures and pressures with small errors. Verification of thermobarometers showed the maximum error in liquidus temperature reproducing does not exceed ±7 °C. The level of cumulative magnetite appearance in the vertical structure of Tsypringa, Kivakka, Burakovsky intrusions predicted with errors from ±10 to ±50 m.

Modern determinants of endometrium hyperplastic processes pathogenesis

2016 ◽  
pp. 137-142
Author(s):  
V.O. Benyuk ◽  
◽  
V.M. Goncharenko ◽  
T.R. Nykoniuk ◽  
◽  
...  
Keyword(s):  
Conservative Therapy ◽  
Solid Phase ◽  
Research Direction ◽  
Immunohistochemical Method ◽  
Results Of Treatment ◽  
Treatment And Prevention ◽  
Receptor Phenotype ◽  
The Relationship ◽  
Endometrial Proliferation

The objective: to еxplore the relationship between the activity of endometrial proliferation and the state of the local immune response in the uterus in the conditions berprestasi process. Patients and methods. Examined 228 women of reproductive and perimenopausal age with endometrial pathology using ultrasound and then performing hysteroresectoscopy. Determination of the concentrations of the cytokines IL-1, IL-2, IL-6 and TNF was performed by solid phase ELISA. Results. Found a trend that confirms the loss of sensitivity to hormones at the stage of malignancy of the endometrium and can be used as diagnostic determinants in determining the nature of intrauterine pathology and criterion of the effectiveness of conservative therapy. Conclusion. Improving etiopatogenetice approach to the therapy of hyperplastic proce.sses of endometrium with determination of receptor phenotype of the endometrium is a research direction in modern gynecology, which will help to improve the results of treatment and prevention of intrauterine pathology. Key words: endometrial hyperplasia,the receptors for progesterone and estrogen, immunohistochemical method.

Calculating the aerodynamics of vertical axis wind turbines

2012 ◽  
Vol 34 (3) ◽  
pp. 169-184 ◽  
Author(s):  
Hoang Thi Bich Ngoc
Keyword(s):  
Wind Turbine ◽  
Incidence Angle ◽  
Vertical Axis ◽  
Rotor Blades ◽  
Vertical Axis Wind Turbine ◽  
Horizontal Axis Wind Turbine ◽  
Velocity Triangle ◽  
Relationship Of ◽  
The Relationship

Vertical axis wind turbine technology has been applied last years, very long after horizontal axis wind turbine technology. Aerodynamic problems of vertical axis wind machines are discussible. An important problem is the determination of the incidence law in the interaction between wind and rotor blades. The focus of the work is to establish equations of the incidence depending on the blade azimuth, and to solve them. From these results, aerodynamic torques and power can be calculated. The incidence angle is a parameter of velocity triangle, and both the factors depend not only on the blade azimuth but also on the ratio of rotational speed and horizontal speed. The built computational program allows theoretically selecting the relationship of geometric parameters of wind turbine in accordance with requirements on power, wind speed and installation conditions.

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