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Substance S

In addition to the case of a metal in contact with its ions in solution there are other cases in which a Galvani potential difference between two phases may be found. One case is the innnersion of an inert electrode, such as platinum metal, into an electrolyte solution containing a substance S that can exist m either an oxidized or reduced fomi tlirough the loss or gain of electrons from the electrode. In the sunplest case, we have... [Pg.598]

The product Ha r then represents the total rate of production of substance s by chemical reaction within the micropore, while represents the flux... [Pg.81]

Hydrocarbons are divided into two mam classes aliphatic and aromatic This classifi cation dates from the nineteenth century when organic chemistry was devoted almost entirely to the study of materials from natural sources and terms were coined that reflected a substance s origin Two sources were fats and oils and the word aliphatic was derived from the Greek word aleiphar meaning ( fat ) Aromatic hydrocarbons irre spective of their own odor were typically obtained by chemical treatment of pleasant smelling plant extracts... [Pg.57]

Both molarity and formality express concentration as moles of solute per liter of solution. There is, however, a subtle difference between molarity and formality. Molarity is the concentration of a particular chemical species in solution. Formality, on the other hand, is a substance s total concentration in solution without regard to its specific chemical form. There is no difference between a substance s molarity and formality if it dissolves without dissociating into ions. The molar concentration of a solution of glucose, for example, is the same as its formality. [Pg.15]

Theoretical Models of the Response Surface Mathematical models for response surfaces are divided into two categories those based on theory and those that are empirical. Theoretical models are derived from known chemical and physical relationships between the response and the factors. In spectrophotometry, for example, Beer s law is a theoretical model relating a substance s absorbance. A, to its concentration, Ca... [Pg.675]

For a sample substance (S) for which an isotope ratio (R ) has been measured and then compared with the same isotope ratio (R ) for a standard substance (A),... [Pg.359]

If a sample substance (S) has been compared against one standard compound (A) to give but comparison with another standard (B) is required (5sb)> then this change can be effected easily if the relation between the two standards 5, 8 is known (Figure 48.4). For delta values, the order in which the suffixes appear is important. For a sample S measured against reference substance A, delta is written as 5sa- This is not the same as 6 5, as can be seen in Figure 48.4. [Pg.359]

Refra.ctive Index. The relative amount of light reflected by a surface is dependent on both components of the iaterface, ie, filler and air. The refractive iadex is a measure of a substance s tendency to reflect light according to Fresnel s equation ... [Pg.368]

Electrophoresis uses the force of an apphed electric field to move molecules or particles, often through a polymer matrix. The electric field acts on the intrinsic charge of a substance, and the force on each substance is proportional to the substance s charge or surface potential. The resulting force on the substance results in a distinct velocity for the substance that is proportional to the substance s surface potential. If two different substances have two different velocities, an electric field apphed for a fixed amount of time results in different locations on the matrix for these substances. [Pg.178]

ODOUR THRESHOLD The minimum concentration of a substance at which the majority of test subjects can detect and identify the substance s characteristic odour. [Pg.16]

Measurement of specific chemical or biological contaminants can be very expensive. Before expending time and money to obtain measurements of indoor air pollutants, you must decide how the results will be used (e.g., comparison to standards or guidelines, comparison to levels in complaint-free areas) what substances(s) should be measured where to take, samples when to take samples what sampling and analysis method to use so that the results provide useful information. [Pg.225]

Deteniiiiiing file fire potential of a fuel is best accomplished fiirough an evaluation of file fuel s flanunability cliaracteristics. No single factor, however, defines a substance s flanunability. When a flanunability comparison is to be made between different substances, file following factors should be considered ... [Pg.204]

For the overwhelming majority of substances encountered in industry, there are not enough data on toxic responses of humans to permit an accurate or precise assessment of the substance s hazard potential. Frequently, the only data available are from controlled experiments conducted with laboratory animals. In such cases, it is necessary to extrapolate from effects observed in animals to effects likely to occur in... [Pg.340]

Pekannuss, /. pecan nut, pecan, pektin-artig, a. pectin-like, -ig, a. pectinous. Pektin-korper, m. pectic substance, -s ure, /. pectic acid, -stoff, m., -substanz, /. pectio substance, -zucker, m. arabinose. pelagisch, a. pelagic. [Pg.334]

Common packaging materials are a potential source of aggressive substance s, and careful selection is recommended to avoid surface deterioration. Where paper is in contact with aluminium, the chloride content should be below 0-05 7o, sulphate content below 0-25 7o, copper content below 0-01% and the pH of aqueous extracts in the range pH 5-5-7-5, in order to avoid corrosion in damp conditions. Papers and felts used in building applications should also conform to this specification as a minimum requirement and be of the highest quality, since metallic copper found in materials of inferior origin can result in severe local galvanic attack of aluminium. [Pg.675]

Furchgott and Zawadzki [1] first discovered that endothelial cells release a substance(s) responsible for the relaxation of vascular smooth muscle by acetylcholine this substance was named endothelium-derived relaxing factor (EDRF). This epoch-making discovery answers the question raised for nearly one hundred years by pharmacologists about why vascular smooth muscle is relaxed by acetylcholine, which however elicits contraction of the other smooth muscles. Because of its instability, the true chemical nature of EDRF was not easily identified. Several years later, several research groups independently found that the biological activities and biochemical properties of EDRF were identical... [Pg.855]

Changes to the active substance(s), such as use of different salts, complexes, isomers, or slightly different biological materials. [Pg.155]

Chapter 1 Public Health Statement The Public Health Statement can be a useful tool for educating patients about possible exposure to a hazardous substance. It explains a substance s relevant toxicologic properties in a nontechnical, question-and-answer format, and it includes a review of the general health effects observed following exposure. [Pg.7]

The structure and mathematical expressions used in PBPK models significantly simplify the true complexities of biological systems. If the uptake and disposition of the chemical substance(s) is adequately described, however, this simplification is desirable because data are often unavailable for many biological processes. A simplified scheme reduces the magnitude of cumulative uncertainty. The adequacy of the model is, therefore, of great importance, and model validation is essential to the use of PBPK models in risk assessment. [Pg.98]


See other pages where Substance S is mentioned: [Pg.288]    [Pg.81]    [Pg.81]    [Pg.522]    [Pg.355]    [Pg.289]    [Pg.290]    [Pg.372]    [Pg.235]    [Pg.291]    [Pg.181]    [Pg.522]    [Pg.164]    [Pg.522]    [Pg.292]    [Pg.94]    [Pg.95]    [Pg.807]    [Pg.627]    [Pg.489]    [Pg.240]    [Pg.241]    [Pg.39]    [Pg.687]    [Pg.167]    [Pg.1021]    [Pg.2440]    [Pg.90]   
See also in sourсe #XX -- [ Pg.371 ]




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