Verification of accuracy of standard thermodynamic data of inorganic electrolytes

2009 ◽  
Vol 75 (1) ◽  
pp. 21-31 ◽  
Author(s):  
Jan Balej
Keyword(s):  
Solid State ◽  
Thermodynamic Data ◽  
Saturated Solution ◽  
The Other ◽  
Good Reliability ◽  
Verification Method ◽  
The Given ◽  
Aqueous Standard ◽  
Mean Activity Coefficients

Accuracy of standard thermodynamic data for some inorganic electrolytes of the types 1-1, 1-2 and 2-1 at 25 °C, in the solid state or aqueous standard solutions, presented in NBS Tables (1982), has been checked. For the purpose, the condition for the pure solid–saturated solution equilibrium and reliable values of solubilities, mean activity coefficients and water activity in saturated solution at the given temperature were used. In most cases, a very good reliability and consistency of all relevant data have been found. On the other hand, some discrepancies have been observed for NaNO3, NaClO4/NaClO4 pair, Na2HPO4·12H2O/Na2HPO4 pair, K2CrO4, K2Cr2O7, (NH4)2SO4 and SrCl2·6H2O/SrCl2 pair the reason of which is not yet known. The verification method can be used for the determination of lacking thermodynamic data. The method has been applied to ΔGşf,cr of NaCNS·2H2O, NaH2PO4·2H2O, Na2CrO4·6H2O, Na2WO4·2H2O, MgI2·8H2O and CaCl2·6H2O at 25 °C. A suitable method has been used for the determination of the most probable solubility in the case when the values scatter. The used methods are applicable to all types of electrolytes and nonelectrolytes.

scholarly journals Determination of the Ratios of Ligands to Metal Ion of some Metal Complexes of Triazoles by Using Eleetronie Speetra in Organie Solvents

2004 ◽  
Vol 1 (1) ◽  
pp. 110-115
Author(s):  
Baghdad Science Journal
Keyword(s):  
Solid State ◽  
Metal Complexes ◽  
Electronic Spectra ◽  
Metal Ion ◽  
The Other ◽  
Molar Ratio ◽  
Other Hand

We found that 4,5- diphenyl- 3(2- propynyl) thio- 1??-triazole [1? forms a complex with Pd (11) ion of ratio 1:1 which absorbs light in CH2CI2 at 400 nm, and 4,5- diphenyl- 3(2- propenyl) thio- 1,2,4- triazole [II] forms complexes with Pd (II) ion of ratio 1:1 which absorbs light at 390 nm, and of ratio 2:1 which absorbs light at 435 nm. On the other hand, we found that the new derivative 4- phenyl- 5( p- amino phenyl) -3- mercapto- 1,2,4- triazole ?111? forms complexes with Cu (II) ion of the ratio 1:1 which absorbs light at 380 nm, with Ni (II) ion of the ratio 3:1 which absorbs light at 358 nm; and with Co (11) ion of the ratio 3.2:1 which absorbs light at 588 nm. The ratio of the complexes were determined by measuring the electronic spectra of the complexes in CH2G2 and (CH^NCHO at different concentrations ofthe ligands and f?xed ' •' of the metal ion in every case, then applying the molar ratio plots on the data. Our results were confirmed by precipitating most ofthe above complexes in solid state, and then each complex was analyzed elementally.

Untersuchungen zum ternären System Bi/Te/O, III. Bestimmung thermodynamischer Daten der ternären Verbindungen/Investigations on the Ternary System Bi/Te/O,III. Determination of Thermodynamic Data of Ternary Compounds

1999 ◽  
Vol 54 (2) ◽  
pp. 252-260 ◽  
Author(s):  
P. Schmidt ◽  
C. Hennig ◽  
H. Oppermann
Keyword(s):  
Solid State ◽  
Ternary System ◽  
Thermodynamic Data ◽  
Phase Relations ◽  
Solid State Reactions ◽  
Enthalpies Of Formation ◽  
Ternary Compounds ◽  
Heats Of Solution

The phase relations in the ternary system Bi/Te/O have been determined in previous studies by solid state reactions. Thermodynamical data have now been obtained for the pertinent equilibria. The heats of solution of Bi2O3, Bi12TeO20, Bi10Te2O19, Bi16Te5O34, Bi2TeO5, Bi2Te2O7, Bi2Te4O11 and TeCl4 were determined in 4N HCl. From these the enthalpies of formation of bismuth tellurites at 298 K have been derived:⊿H°b (Bi12TeO20, f, 298) = -901,6 ± 8 kcal/mol,⊿H°b (Bi10Te2O19, f, 298) = -856,1 ± 9 kcal/mol,⊿H°b (Bi16Te5O34, f, 298) = -1519,5 ± 17 kcal/mol,⊿H°b (Bi2TeO5, f, 298)= -222,8 ± 3 kcal/mol,⊿H°b (Bi2Te2O7, f, 298)= -299,4 ± 4 kcal/mol,⊿H°b (Bi2Te4O11, f, 298)= -448,2 ± 7 kcal/mol.

Estimation of Lacking Standard Thermodynamic Data of Peroxodisulfates at 0–50 °C

2010 ◽  
Vol 224 (06) ◽  
pp. 883-892 ◽  
Author(s):  
Jan Balej
Keyword(s):  
Solid State ◽  
Thermodynamic Data ◽  
Reliable Data ◽  
Estimation Methods ◽  
Solid Substance ◽  
Sodium Potassium ◽  
Formation Enthalpies ◽  
Formation Energies ◽  
Mean Activity Coefficients ◽  
Ammonium Peroxodisulfate

AbstractEstimated standard formation enthalpies and standard entropies of solid sodium and ammonium peroxodisulfate enabled to estimate standard Gibbs formation energies of these substances in the solid state at 25 °C. Their reliability was checked on the basis of the thermodynamic condition for the equilibrium between the solid substance and its saturated solution, in combination with estimated mean activity coefficients of the saturated solutions and with reliable data of standard Gibbs formation energies in the aqueous solutions. Using suitable estimation methods for the temperature dependence of the appropriate C°p data, the corresponding values ΔfH° and ΔfG° of sodium, potassium and ammonium peroxodisulfates in the standard solid and aqueous state at 0–50 °C have been derived.

Sobre a Natureza das Proposições Silogísticas em Aristóteles

2006 ◽  
Vol 14 (28) ◽  
pp. 15-32
Author(s):  
António Pedro Mesquita ◽  
Keyword(s):  
The Other ◽  
Other Hand ◽  
State Relations ◽  
The Given

The aim of this paper is to clarify and support the following hypothesis: the four propositional forms of Aristotelian syllogistics (AaB, AeB, AiB, AoB) state relations between universals, or are primarily conceptual. We characterize as “conceptual” those propositions which deal only with concepts and ignore any reference to objects. In a conceptual proposition, therefore, the reference is tacitly present in the simple occurrence of the terms, but is neutralised or cancelled out, because it is only the intension of these terms, that is, the concepts, which are dealt with in the proposition. On the other hand, we characterize as “objectual” those propositions (whether extensional or intensional in modem terms) which deal directly or indirectly of objects, even when, as it is often the case, a concept has to be assumed in the determination of these objects. In the present paper we try to confirm this hypothesis, by answering the following questions: (i) how to interpret the kind of predication present in each type of syllogistic proposition; (ii) if these predications really express relations between universals in the given sense and, therefore, if the propositions that express them are conceptual propositions in this sense; and to what measure can these propositions serve to introduce, also, objectual propositions.

scholarly journals Determination of quasi-primary odors by endpoint detection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hanxiao Xu ◽  
Koki Kitai ◽  
Kosuke Minami ◽  
Makito Nakatsu ◽  
Genki Yoshikawa ◽  
...  
Keyword(s):  
Machine Learning ◽  
Arbitrary Number ◽  
The Other ◽  
Endpoint Detection ◽  
Alternative Approach ◽  
The Given

AbstractIt is known that there are no primary odors that can represent any other odors with their combination. Here, we propose an alternative approach: “quasi” primary odors. This approach comprises the following condition and method: (1) within a collected dataset and (2) by the machine learning-based endpoint detection. The quasi-primary odors are selected from the odors included in a collected odor dataset according to the endpoint score. While it is limited within the given dataset, the combination of such quasi-primary odors with certain ratios can reproduce any other odor in the dataset. To visually demonstrate this approach, the three quasi-primary odors having top three high endpoint scores are assigned to the vertices of a chromaticity triangle with red, green, and blue. Then, the other odors in the dataset are projected onto the chromaticity triangle to have their unique colors. The number of quasi-primary odors is not limited to three but can be set to an arbitrary number. With this approach, one can first find “extreme” odors (i.e., quasi-primary odors) in a given odor dataset, and then, reproduce any other odor in the dataset or even synthesize a new arbitrary odor by combining such quasi-primary odors with certain ratios.

scholarly journals The optimum temperature of salicin hydrolysis by enzyme action is independent of the concentrations of substrate and enzyme

1914 ◽  
Vol 87 (594) ◽  
pp. 245-254 ◽  
Keyword(s):  
Enzyme Concentration ◽  
The Other ◽  
Optimum Temperature ◽  
Constant Concentration ◽  
M 10 ◽  
The One ◽  
The Given ◽  
Hydrolysis Of ◽  
Preliminary Determination

The object of the present investigation is to ascertain the influence, if any, on the optimum temperature—temperature of greatest activity—of an enzyme, of the concentration, on the one hand, of the substrate, and, on the other, of the enzyme. The investigation, involving two variables, presents three cases for consideration, according as the concentration of the substrate and the concentration of the enzyme are varied separately or together. An account is given of the results obtained with the enzyme or enzymic function, present in sweet-almond emulsin, which hydrolyses the glucoside salicin with the production of equimolecular quantities of glucose and saligenin. A commercial specimen of Merck’s emulsin was used, while the purity of the salicin employed was ascertained by determining its melting point (200-5°) and its optical activity ([ α ] 21 D = -62·7°). The successive stages in the inquiry may be briefly summarised as follows: (1) a preliminary determination of the activity of the specimen under certain chosen conditions as regards the concentration of the substrate, the temperature, and the duration of the experiment; (2) a preliminary determination of the optimum temperature with the quantity of enzyme found capable of producing 50 per cent, hydrolysis of the substrate under the above conditions; (3) a determination of the activity curves of the enzyme at the temperature thus found, in an action of the same duration for five concentrations of the substrate M/5, M/10, M/15, M/30, and M/50; (4) a determination of the optimum temperature of the enzyme for each of the five concentrations of the substrate in presence of a constant enzyme concentration ; (5) a determination of the optimum temperature of the enzyme for each of the five concentrations of the substrate with quantities of enzyme indicated by the activity curves as capable of producing 70 per cent, hydrolysis of the substrate in the given time: (6) a determination of the optimum temperature of the enzyme for a constant concentration of the substrate in presence of different enzyme concentrations.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

Procedures for the Quantitative Determination of Autoprothrombin C

1962 ◽  
Vol 08 (03) ◽  
pp. 434-441 ◽  
Author(s):  
Edmond R Cole ◽  
Ewa Marciniak ◽  
Walter H Seegers
Keyword(s):  
Quantitative Determination ◽  
Plasma Sample ◽  
Quantitative Measure ◽  
The Other ◽  
Clotting Time ◽  
Bovine Plasma ◽  
Autoprothrombin C

SummaryTwo quantitative procedures for autoprothrombin C are described. In one of these purified prothrombin is used as a substrate, and the activity of autoprothrombin C can be measured even if thrombin is in the preparation. In this procedure a reaction mixture is used wherein the thrombin titer which develops in 20 minutes is proportional to the autoprothrombin C in the reaction mixture. A unit is defined as the amount which will generate 70 units of thrombin in the standardized reaction mixture. In the other method thrombin interferes with the result, because a standard bovine plasma sample is recalcified and the clotting time is noted. Autoprothrombin C shortens the clotting time, and the extent of this is a quantitative measure of autoprothrombin C activity.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

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