Some Basic Definitions

We need to begin with several definitions of terms used throughout. (For an introduction to chemical kinetics see [1].) 

Elementary reaction. The term elementary reaction has been defined. Sometimes two or more elementary reactions are added, as for example the elementary steps in a Michaelis-Menten enzymatic reaction, and listed as a pseudo-elementary reaction. Catalyst. Acatalyst may be necessary for an elementary reaction to occur at a reasonable rate, as well as positive and negative effectors on the catalyst. We shall be concerned mostly with isothermal reactions. 

Reaction mechanism. A series of elementary reaction steps, usually postulated, that leads from stated reactants to products, including catalysts and effectors, is called the reaction mechanism for that overall reaction. An example of an important biological reaction mechanism, a part of glycolysis, is shown in fig. 1.2. 

Reaction pathway. A listing of sequential chemical species in a reaction mechanism is called a reaction pathway for example, the sequence glucose 6-phosphate, fructose 6-phosphate, fructose 1,6-bisphophate (see fig. 1.2) is a reaction pathway in the glycolysis reaction mechanism. 

Causal connectivity. The direct connection of one species, say glucose, to another, glucose 6-phosphate, by reaction is called causal connectivity. A sequence of causal connectivities gives a reaction pathway from which a reaction mechanism, or parts thereof, may be inferred. There will be more on this subject later. 

Before a detailed discussion of health and safety issues can take place, some basic occupational health and safety definitions are required  

Health - the protection of the bodies and minds of people from illness resulting from the materials, processes or procedures used in the workplace. 

Safety - the protection of people from physical injury. The borderline between health and safety is ill-defined and the two words are normally used together to indicate concern for the physical and mental well-being of the individual at the place of work. 

Occupational or work-related ill-health - is concerned with those illnesses or physical and mental disorders that are either caused or triggered by workplace activities. Such conditions may be induced by the particular work activity of the individual or by activities of others in the workplace. The time interval between exposure and the onset of the illness may be short (e.g. asthma attacks) or long (e.g. deafness or cancer). 

Environmental protection - arrangements to cover those activities in the workplace which affect the environment (in the form of flora, fauna, water, air and soil) and, possibly, the health and safety of employees and others. Such activities include waste and effluent disposal and atmospheric pollution. 

In Chapter 1, we described, in a rather broad sense, various classes of electrodes. In the study of voltammetry a more specific definition is required. Voltammetry is the study or measurement of the current-voltage relations which exist at the face of an electrode immersed in a solution which contains electroactive species. For our purposes, the solution will be an aqueous electrolyte. 

We are primarily concerned with solid electrodes, and throughout this text this will mean, for the most part, platinum, gold, silver, and stainless steel. A working electrode now may be defined as any electrode through 

Normally, an electrode system consists of an active or working electrode, an indifferent or reference electrode, and an electrolyte with which the electrodes are in mutual contact. Define as the potential of an electrode which is sustaining a net anodic or cathodic reaction. Let be the electrode s equilibrium value (no net reaction). Thus the total overpotential of the electrode (total polarization potential), Vj, is defined by 

The ohmic overpotential is defined by a linear voltage-current relationship at the electrode (Ohm s law). It is derived from a cell in which the electrolyte resistance R is finite with current / passing through the cell. Hence a simple IR drop occurs. 

The concentration overpotential results from continued electrolysis, which causes the ionic concentrations at the electrode surface to differ from those in the bulk solution. See Kolthoff and Lingane (1952) for a detailed analysis. is the principal overpotential in voltammetric measurements. 

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Table 2-4. Some basic definitions for graph theory. Graph theory term...

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The technique of risk assessment is used in a wide range of professions and academic subjects. Accordingly, in this introductory section some basic definitions are necessary. 

A.D Amico, C.DiNatale. A contribution on some basic definitions of sensors properties. Sensors Journal, IEEE, vol. 1, Issue 3, Oct 2001 Page(s) 183 - 190... 

What is new about components If they are reusable software pieces, how are they different from modules If they are like objects, in what ways are they different At the most basic level, components are parts that can be composed with others to build something bigger. Let s start with some basic definitions. 

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Fundamental principles of catalysis some basic definitions... 

There are some common characteristics for gas-phase reaction systems that form the basis for understanding and describing the chemical behavior. In this section we will discuss some basic definitions and terms that are useful in kinetics, such as reaction order, molec-ularity, chain carriers, rate-limiting steps, steady-state and partial equilibrium approximations, and coupled/competitive reactions. 

In this chapter we introduce some basic definitions for graphs, maps, and polyhedra. We present here the basic notions. Further definitions will be introduced later when needed. The reader can consult the following books for more detailed information [Gru67], [Cox73], [Mun71], [Cro97]. 

This section reviews some basic definitions and formulas in thermodynamics. These definitions will be used to develop energy balances to describe cooling tower operations. In our discussions we will use the following terms system, property, extensive and intensive properties, and... 

Briefly, we recall some basic definitions involving the short-order structural functions typical of the liquid state and their relationships with thermodynamic quantities. Considering a homogenous fluid of N particles, enclosed in a definite volume V at a given temperature T (canonical ensemble), the two-particles distribution function [7, 9, 17, 18] is defined as... 

We first review some basic definitions required for our proofs and derivations ... 

Before we discuss the viscoelastic properties of nonuniform fractal structures we shall give some basic definitions from the theory of elasticity. 

In this Chapter, we quickly review some basic definitions and concepts from thermodynamics. We then provide a brief description of the first and second laws of thermodynamics. Next, we discuss the mathematical consequences of these laws and cover some relevant theorems in multivariate calculus. Finally, free energies and their importance are introduced. 

It will be uselul for the reader to establish some basic definitions related to the topic before we proceed. The main component of the textile or nonwoven fabric is the fiber therefore, polyolefin fiber will be defined first. 

Figure 63 Some basic definitions and values for hot streams.

Some Basic Definitions, Physical Constants, Units,... 

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