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Quality of a solution

Such a string may be useful when two types of variables independently affect the quality of a solution. Suppose that an analytical laboratory monitors the air quality at a downtown site, measuring the level of fifteen different pollutants. A theoretical model is established that links the amount of these pollutants measured at the monitoring point with the amounts of each pollutant released at twenty different sites around the city. Because there are fifteen pollutants and twenty pollution sources, a 15 x 20 matrix is required to model the problem and GA strings can be constructed in this form. [Pg.147]

I our environment is made up of many important solutions, or homogeneous mixtures. The air you breathe and the liquids you drink are solutions. So are many of the metallic objects that you use every day. The quality of a solution, such as tap water, depends on the substances that are dissolved in it. Clean water may contain small amounts of dissolved substances, such as iron and chlorine. Dirty water may have dangerous chemicals dissolved in it. [Pg.283]

These acid- or alkaline-balanced products may be advertised as pH balanced. But what does pH mean We can get a clue from revisiting the pool test kit. The phenol red indicator is also labeled pH indicator pH is a measure of how acidic or basic a solution is. It is a measure of the acid quality of a solution. [Pg.92]

Fitness function The fitness function is a mathematical function or a computer algorithm that describes the quality of a solution. It is necessary for the final decision as to whether an optimization was achieved. The fitness function should be able to distinguish between the individual chromosomes but should be able to recognize similarities, too. [Pg.110]

Fitness Function is a mathematical function or a computer algorithm that describes the quality of a solution in a genetic algorithm. [Pg.113]

Its objective is to select tiie best possible decision for a given set of circumstances without having to enumerate all of the possibilities and involves maximization or minimization as desired. In optimization decision variables are variables in the model which you have control over. Objective function is a fimction (mathematical model) that quantifies the quality of a solution in an optimization problem. Constraints must be considered, conditions that a solution to an optimization problem must satisfy and restrict decision variables are determined by defining relationships among them. It must be found the values of die decision variables that maximize (minimize) the objective function value, while staying widiin the constraints. The objective function and all constraints are linear functions (no squared terms, trigonometric functions, ratios of variables) of the deeision variables [59, 60]. [Pg.257]

In the style of the Darwinian Theory, the quality of a chromosome is called its fitness. The quality or fitness of a ehromosome is usually caleulated with the help of an objeetive function, which is a mathematical function indicating how good the solution, and thus the chromosome, is for the optimization problem. This computation of the fitness is done for each chromosome in each population,... [Pg.469]

These workers used binary solvent systems over a range of mole fractions to determine, for each solute, the constants a and b of equation (8.2). For methyl and phenacyl esters, TLC was used, while overpressured layer chromatography (OPLC) was used for dansyl amino acids. Nurok and co-workers (11) also evaluated how the quality of a simulated separation varies with changing solvent strength by using the inverse distance function (IDF) or planar response function (PRF), as follows ... [Pg.176]

A common laboratory technique for determining the concentration of a solute is titration (Fig. L.2). Titrations are usually either acid-base titrations, in which an acid reacts with a base, or redox titrations, in which the reaction is between a reducing agent and an oxidizing agent. Titrations are widely used to monitor water purity and blood composition and for quality control in the food industry. [Pg.111]

A population of solutions is created and each member of it is tested to determine how good it is. If there is no solution in the population whose quality is acceptable, the solutions are manipulated by picking the better ones and modifying them to form a fresh population whose members are tested in turn. This cyclic process continues over many generations, during which the population improves until, one hopes, a solution of suitable quality emerges. The entire process, from the preparation of the first population to the final identification of a solution of near-optimum quality, makes up a GA run. [Pg.117]

Different measures of the quality of the solution can be used for scheduling problems. However, the criterion selected to be optimized usually has a direct effect on the model computational performance. In addition, some objective functions can be very hard to implement for some event representations, requiring additional variables and complex constraints. [Pg.172]

Primary standard sodium carbonate may also be used to standardize acid solutions. Sodium carbonate also possesses all the qualities of a good primary standard, like KHP and THAM. When titrating sodium carbonate, carbonic acid, H2C03, is one of the products and must be decomposed with heat to push the equilibria below to completion to the right ... [Pg.106]

Just as a consumer may judge the quality of a product by its resistance to flow, so also quality assurance technicians in the chemical process industries may judge the quality of a fluid material or product by its resistance to flow. Examples include solutions of polymers (where a solution s resistance to flow is indicative of the quality of the undissolved polymer), asphalt formulations for roads and parking lots, lubricating oils, etc. [Pg.419]

Especially concerning substances involved in pubhc scandals , decisions to substitute are then taken underpressure , in which the enviromnent and health-related quality of substitution solutions remains to a large extent open and mere shifts of risks are probable. [Pg.99]

Geminal functional theory is a very promising research area. The different varieties of antisymmetrized products are very flexible and inherently handle difficult problems, like multideterminantal molecules. The computational effort is low compared to the quality of the solutions. The perturbation theoretical approach to SSG should essentially be possible for AGP and UAGP as well. The formal definition of GFT is a flexible framework that opens up many new opportunities for exploring the nature of solutions to the Schrodinger equation. [Pg.439]

The properties of solutions of macromolecular substances depend on the solvent, the temperature, and the molecular weight of the chain molecules. Hence, the (average) molecular weight of polymers can be determined by measuring the solution properties such as the viscosity of dilute solutions. However, prior to this, some details have to be known about the solubility of the polymer to be analyzed. When the solubility of a polymer has to be determined, it is important to realize that macromolecules often show behavioral extremes they may be either infinitely soluble in a solvent, completely insoluble, or only swellable to a well-defined extent. Saturated solutions in contact with a nonswollen solid phase, as is normally observed with low-molecular-weight compounds, do not occur in the case of polymeric materials. The suitability of a solvent for a specific polymer, therefore, cannot be quantified in terms of a classic saturated solution. It is much better expressed in terms of the amount of a precipitant that must be added to the polymer solution to initiate precipitation (cloud point). A more exact measure for the quality of a solvent is the second virial coefficient of the osmotic pressure determined for the corresponding solution, or the viscosity numbers in different solvents. [Pg.16]

Among the large number of existing lipophilicity parameters [31], the descriptor frequently estimated by in silica methods is the partition coefficient of a solute between 1-octanol and water, expressed as log Poet [32]. However, lipophilicity determination in different solvent systems, such as alkane/water system, proved its utility in (Q)SAR studies and therefore some predictive methods also emerged in this field. Many publically available databases include numerous experimental values collected through the literature the quality of the experimental data represents the cornerstone of most of the models developed to predict lipophilicity. [Pg.92]

Since the measurement of efficiency is Important for evaluating the quality of a column, it is necessary to know the position of the points of inflection in order to measure the peak width. The inflection points are ill defined on the chromatogram and it is necessary to know at what fraction of the peak height they occur. This fraction will be the same as the ratio of the value of the solute concentration after (n - Vn) plate volumes of mobile phase has passed through the column, to the solute concentration after (n) plate volumes of mobile phase has passed through the column. [Pg.48]

Thus, the approximate value of Hmin, for a well retained solute eluted from a well packed column and operated at the optimum linear mobile phase velocity, can be expected to be about 2.48dp, Furthermore, to the first approximation, this value will be independent of the nature of the solute, mobile phase or stationary phase. For the accurate design of the optimum columns lor a particular separation however, this approximation can not be made, nevertheless, the value of 2.48 for Hmin is a useful guide for assessing the quality of a column. [Pg.115]


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See also in sourсe #XX -- [ Pg.121 ]




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