STUDIES ON THE SYSTEM CALCIUM-OXIDE–SULPHUR-DIOXIDE–WATER: I. DETERMINATION OF VAPOR PRESSURES AND CONDUCTIVITIES

1935 ◽  
Vol 13b (4) ◽  
pp. 209-217 ◽  
Author(s):  
G. W. Gurd ◽  
P. E. Gishler ◽  
O. Maass
Keyword(s):  
Calcium Oxide ◽  
Sulphur Dioxide ◽  
Tabular Form ◽  
Vapor Pressures ◽  
Temperature Range ◽  
The Way

The system calcium-oxide–sulphur-dioxide–water is to be investigated in order to determine the nature of existing equilibria, and the way in which these vary with concentration and temperature. In this paper a technique is described by means of which vapor pressures and conductivities have been measured over the temperature range 25° to 130 °C. and over the concentration range 0 to 2.5% CaO and 0 to 6% SO2. The data obtained are systematized in tabular form.

scholarly journals AN INVESTIGATION OF THE EQUILIBRIA EXISTING IN GAS-WATER SYSTEMS FORMING ELECTROLYTES

1931 ◽  
Vol 5 (2) ◽  
pp. 162-199 ◽  
Author(s):  
O. M. Morgan ◽  
O. Maass
Keyword(s):  
Carbon Dioxide ◽  
Aqueous Solutions ◽  
Sulphur Dioxide ◽  
Carbonic Acid ◽  
Ammonium Hydroxide ◽  
Theoretical Treatment ◽  
Vapor Pressures ◽  
Temperature Range ◽  
Free Carbon Dioxide ◽  
Order Of Magnitude

The data and theoretical treatment contained in this paper are the continuation of a series of researches instituted to investigate the equilibria existing in certain gaseous-aqueous systems. In this work the vapor pressures and electrolytic conductivities of aqueous solutions of sulphur dioxide, carbon dioxide, and ammonia have been measured with greater precision than ever before over a temperature range from 0 to 25 °C. and over a concentration range where their respective vapor pressures do not exceed one atmosphere. From the data thus derived, equilibria relations have been calculated and certain changes have been made in the mode of theoretical procedure involved in this type of calculation.With regard to the equilibria existing in the three systems, the conclusions drawn may be summarized as follows: Practically all of the ammonia exists in the combined form and practically all the carbon dioxide exists as free carbon dioxide in the aqueous solutions in the temperature range investigated. The amounts of free and combined sulphur dioxide are of the same order of magnitude and the relative amount of combined and free sulphur dioxide can be calculated approximately, the latter increasing markedly with rising temperature. The true dissociation constant can therefore be found for ammonium hydroxide, can be estimated for sulphurous acid, but cannot be calculated for carbonic acid from the available data.

Identifizierung der Zementart in hydratisierten Betonen und Mörteln / Identification of the Type of Cement in Hardened Concretes and Mortars

2000 ◽  
Vol 6 (2) ◽  
pp. 191-218
Author(s):  
F. Splittgerber ◽  
A. Müller
Keyword(s):  
Compressive Strength ◽  
Calcium Oxide ◽  
Cement Paste ◽  
Hardened Concrete ◽  
Portland Cements ◽  
Free Lime ◽  
Temperature Range ◽  
Mineral Phases ◽  
The Difference

Abstract Subject of this paper is the development of a method for the identification of the type of cement present in a hardened concrete or mortar. The method is based on the dehydration of the cement paste and the identification of the phases present after the dehydration. Considering clinker phases and real cements, the following possibilities for the identification of cements were worked out: • differentiation between Portland cements and cements containing additions by the identification of the mineral phases which are typical for the type of the addition • differentiation between ordinary and sulphate resistant Portland cements by the identification of the Ye'elimite phase after a dehydration at a temperature of 1100° C • determination of the characteristic compressive strength of Portland cements by the evaluation of the Alite-content. For an identification at least two dehydration temperatures have to be considered. The first temperature range is at about 1100 to 1200°C. It is important for the identification of the aluminates and ferrites. Temperatures from about 1400 to 1450°C are needed for the dehydration of the silicates. Because of the appearence of melting phases at temperatures above 1200°C, the Alite-content will be determined indirectly by the determination of the Belite-content and the content of free lime after a dehydration at 1100°C. At this temperature the free lime is considered to represent the difference in calcium oxide between the Alite and the Belite.

EQUILIBRIA IN SULPHUR DIOXIDE SOLUTIONS

1930 ◽  
Vol 2 (1) ◽  
pp. 42-64 ◽  
Author(s):  
W. Boyd Campbell ◽  
O. Maass
Keyword(s):  
Aqueous Solutions ◽  
Sulphur Dioxide ◽  
Current Practice ◽  
Water Solution ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Vapor Pressures ◽  
Hydrogen Ion Concentration ◽  
Temperature Range ◽  
Free Sulphur

The investigation described deals with the equilibria existing in a water solution of sulphur dioxide. The vapor pressures and conductivities of solutions of sulphur dioxide were measured over the temperature range 23° to 135 °C. at various concentrations up to 8%. The densities of the aqueous solutions up to 15% were also measured. A discussion of the various equilibria in the light of these data leads to the conclusion that sulphurous acid is one of considerable strength, its apparent weakness being due to the small amount of H2SO3 actually present. With rise in temperature the free sulphur dioxide increases and the hydrogen-ion concentration of the sulphite liquor used in current practice is so low that it seems highly improbable that the cooking reaction is due essentially to this factor. Apart from the bearing this work may have on the theory of sulphite cooking and the theory of the equilibria existing in the SO2−H2O system, it fills a considerable gap in the data regarding sulphur dioxide.

Ronald Coase and the Difference between Markets and Firms

2018 ◽  
Author(s):  
Abraham A. Singer
Keyword(s):  
Transaction Cost ◽  
Economic Activity ◽  
Transaction Cost Economics ◽  
Theory Of The Firm ◽  
Tabular Form ◽  
Specific Investment ◽  
The Difference ◽  
Marginal Revolution ◽  
The Way

This chapter reviews the development of transaction cost economics and unpacks its theory of the firm. The chapter begins with the marginal revolution in economics and how it altered the way economists understood the corporation. It then reviews the work of Ronald Coase and Oliver Williamson, explaining how they provided a novel account of firms. Transaction cost economics emphasizes how firms use hierarchy and bureaucracy to overcome problems of opportunism and asset-specific investment to coordinate some types of economic activity more efficiently than markets can. The transaction cost account of the corporation’s productivity component is shown in tabular form in comparison with its historical forerunners reviewed in the previous chapter.

scholarly journals Modelling and Multi-Objective Optimization of the Sulphur Dioxide Oxidation Process

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1072
Author(s):  
Mohammad Reza Zaker ◽  
Clémence Fauteux-Lefebvre ◽  
Jules Thibault
Keyword(s):  
Sulphuric Acid ◽  
Sulphur Dioxide ◽  
Variable Number ◽  
Inlet Temperature ◽  
Multi Objective Optimization ◽  
Absorption Column ◽  
Maximum Reaction Rate ◽  
Multi Objective ◽  
Maximum Reaction

Sulphuric acid (H2SO4) is one of the most produced chemicals in the world. The critical step of the sulphuric acid production is the oxidation of sulphur dioxide (SO2) to sulphur trioxide (SO3) which takes place in a multi catalytic bed reactor. In this study, a representative kinetic rate equation was rigorously selected to develop a mathematical model to perform the multi-objective optimization (MOO) of the reactor. The objectives of the MOO were the SO2 conversion, SO3 productivity, and catalyst weight, whereas the decisions variables were the inlet temperature and the length of each catalytic bed. MOO studies were performed for various design scenarios involving a variable number of catalytic beds and different reactor configurations. The MOO process was mainly comprised of two steps: (1) the determination of Pareto domain via the determination a large number of non-dominated solutions, and (2) the ranking of the Pareto-optimal solutions based on preferences of a decision maker. Results show that a reactor comprised of four catalytic beds with an intermediate absorption column provides higher SO2 conversion, marginally superior to four catalytic beds without an intermediate SO3 absorption column. Both scenarios are close to the ideal optimum, where the reactor temperature would be adjusted to always be at the maximum reaction rate. Results clearly highlight the compromise existing between conversion, productivity and catalyst weight.

Metabolic response to temperature stress in the Colombian freshwater crab Neostrengeria macropa (H. Milne Edwards, 1853) (Decapoda: Brachyura: Pseudothelphusidae)

2021 ◽  
Author(s):  
David M Hudson
Keyword(s):  
Metabolic Response ◽  
Infrastructure Development ◽  
Predator Prey ◽  
Temperature Range ◽  
Indicator Group ◽  
Response To Temperature ◽  
Performance Results ◽  
The City ◽  
The Ideal

Abstract Freshwater crustaceans are distributed throughout the montane and lowland areas of Colombia, and are therefore a useful indicator group for how aquatic species will respond to climate change. As such, metabolic determination of physiological performance was evaluated for the Colombian pseudothelphusid crab, Neostrengeria macropa (H. Milne Edwards, 1853), over a temperature range inclusive of current temperatures and those predicted by future scenarios in the plateau around the city of Bogotá, namely from 8 °C to 30 °C. The performance results mostly aligned with previous exploratory behavioral determination of the ideal temperature range in the same species, although the metabolism increased at the highest temperature treatments, a point when exploratory behavior declined. These results indicate that this species of montane crab behaviorally compensates for increased thermal stress by decreasing its physical activity, which could have negative predator-prey consequences with changes to community structure as different species undergo climate-mediated geographic range shifts in the region. As this species is endemic to the plateau surrounding Bogotá, it also experiences a number of other stressors to its survival, including infrastructure development and invasive species.

scholarly journals Universal Synthesizer of Mueller Matrices Based on the Symmetry Properties of the Enpolarizing Ellipsoid

Symmetry ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 983
Author(s):  
José J. Gil ◽  
Ignacio San José
Keyword(s):  
Mathematical Structure ◽  
Mueller Matrix ◽  
Morphological Properties ◽  
Nondestructive Analysis ◽  
Structural Decomposition ◽  
Symmetry Properties ◽  
Mueller Matrices ◽  
Scattering Measurement ◽  
The Way

Polarimetry is today a widely used and powerful tool for nondestructive analysis of the structural and morphological properties of a great variety of material samples, including aerosols and hydrosols, among many others. For each given scattering measurement configuration, absolute Mueller polarimeters provide the most complete polarimetric information, intricately encoded in the 16 parameters of the corresponding Mueller matrix. Thus, the determination of the mathematical structure of the polarimetric information contained in a Mueller matrix constitutes a topic of great interest. In this work, besides a structural decomposition that makes explicit the role played by the diattenuation-polarizance of a general depolarizing medium, a universal synthesizer of Muller matrices is developed. This is based on the concept of an enpolarizing ellipsoid, whose symmetry features are directly linked to the way in which the polarimetric information is organized.

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