Primary process various definitions

Just as there are a number of different definitions of "primary photochemical processes," so also does "primary quantum yield" have different meanings in the various photochemical references. It may be defined, for example, as the sum of the quantum yields of all of the events which lead to dissociation or reaction of the excited molecule. In Figure 1, these would be events 24, 15, and 14. An alternate definition is that each one of the individual quantum yields in that sum is itself one of the primary quantum yields. 

Initiation and propagation of water trees depend on a multitude of parameters electric field strength, mechanical stress, type and concentration of ions in the water, constitution of the polymer and its additives, etc. At this stage there is no satisfactory model that explains the process of water treeing. In a comprehensive review, Crine (1998) carefully considers the various types of possible mechanism in relation to a vast amount of experimental investigation, but is unable to come to any definite conclusion about primary mechanisms. Rather surprisingly, oxidation appears to play no major role (Bulinski et al., 1998). It seems only likely that ingress of water, aided by the presence of... 

An important aspect of the function of compounded lubricants is to increase the load that can be carried by machinery without catastrophic damage to the rubbing components. Since the typical antiwear additives affect the viscosity of the carrier oil very little, it is not a fluid film effect that is responsible for the load-carrying augmentation. Examination of the various basic wear processes leads to the choice of the adhesive mechanism as the one most likely to respond to the action of boundary or extreme-pressure additives. The type of macroscopically observed severe wear which has this mechanistic process as its primary cause is generally designated as icu i ng (c(S. Chapter 13, Sections 13.4 and 13.6), and it is in this sense, as a description rather than a definition, that the term scuffing is used in the discussion to follow. 

Many molecular definitions of a gene relate to their role in directing the production of specific proteins. Production of protein itself is made possible via certain enzymes known as polymerases. Various DNAs and RNAs could not be produced without these polymerases and therefore they are of primary importance. Numerous other enzymes are produced that control metabolic and catabolic processes (enzymatically), provide structural components, and perform regulatory functions in cells. 

The job safety analysis (JSA) [also referred to as the job hazard analysis (JHA)], which is a more simplified form of task analysis, has been a longstanding tool for task and function analysis. JSA has been available and utilized in general industry for many years by the industrial safety community. However, many practitioners do not understand or are simply unfamiliar with the connection between the JSA and the system safety tasks of hazard identification and analysis. It has even been suggested by some in the profession that the JSA itself is a type of oversimplified system safety analysis and, if performed earlier in the job development phase, could be used as the basis of a preliminary hazard analysis for a specific task or set of tasks. However, because JSA is often (if improperly) used to analyze a function only after it has been implemented, much of the data is not factored into the system safety process. The primary purpose of the JSA is to uncover inherent or potential hazards that may be encountered in the work environment. This basic definition is not unlike that previously discussed regarding the various system safety analyses. The primary difference between the two is subtle but important and is found in the end-use purpose of the JSA. Once the job or task is completed, the JSA is usually used as an effective tool for training and orienting the new employee into the work environment. The JSA presents a verbal picture of a specific job. 

Radionuclides are released to the containment as gases and as aerosol particles by a variety of processes during severe accidents. Modem, mechanistic analyses of these radionuclide releases and the subsequent behaviour of aerosols and vapours under reactor accident conditions strive to be realistic. This realistic approach contrasts with the deliberate attempt to be conservative (which may not have been successful) in the definition of radionuclide behaviour for the design of nuclear power plant safety systems. A discussion of the various radionuclide release processes during severe reactor accidents is presented in Chapter II. Of primary interest in these discussions of release is the potential magnitude of radionuclide release and the radionuclides of most concern. Factors that most affect radionuclide release but can also be affected by accident management measures are discussed. 

There are currently 15 key federal laws related to the control and regulation of hazardous and toxic materials. A summary of these laws, their regulatory objectives, and primary responsible federal agencies is shown in Table 3.1. In addition there are many more state laws and regulations, often with more stringent requirements than their federal counterparts. It is important to review these state and federal regulations as part of the risk assessment process. The various laws and regulations provide specific definitions, specific lists of toxic and hazardous materials, requirements for compliance, and methods and standards for compliance. 

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