Specific component

Sometimes analyses are required for particular compounds such as sulfur, chlorine and lead, or for specific components such as mercaptans, hydrogen sulfide, ethers and alcohols. 

The saturation coverage during chemisorption on a clean transition-metal surface is controlled by the fonnation of a chemical bond at a specific site [5] and not necessarily by the area of the molecule. In addition, in this case, the heat of chemisorption of the first monolayer is substantially higher than for the second and subsequent layers where adsorption is via weaker van der Waals interactions. Chemisorption is often usefLil for measuring the area of a specific component of a multi-component surface, for example, the area of small metal particles adsorbed onto a high-surface-area support [6], but not for measuring the total area of the sample. Surface areas measured using this method are specific to the molecule that chemisorbs on the surface. Carbon monoxide titration is therefore often used to define the number of sites available on a supported metal catalyst. In order to measure the total surface area, adsorbates must be selected that interact relatively weakly with the substrate so that the area occupied by each adsorbent is dominated by intennolecular interactions and the area occupied by each molecule is approximately defined by van der Waals radii. This... 

The principal component of a mbber compound is the elastomer or blend of elastomers chosen for a specific component appHcation. There are 25—30 different chemical classifications of elastomers six of these classes represent over 90% of all elastomers used (see Elastomers, synthetic). 

An example of the use of polyacrylamide gels in an ief system in combination with immun obi otting is given in Reference 40 where this method is used to detect low quantities of group specific component (GC) subtypes. Another example of polyacrylamide in combination with ief is given in Reference 41 where the technique is used as a screening tool for inheritance of a certain polymorphic protein. 

Once a decision has been made to recover materials and/or energy, process flow sheets must be developed for the removal of the desired components, subject to predetermined materials specifications. A typical flow sheet for the recovery of specific components and the preparation of combustible materials for use as a fuel source is presented in Fig. 25-63. The light combustible materials are often identified as refuse-derived fuel (RDF). 

The probability a specific component (or collection of components) is contributing to a system failure, given that the system is failed... 

The inadequacy of the worst case model is evident and the statistical nature of the tolerance stack is more realistic, especially when including the effects of shifted distributions. This has also been the conclusion of some of the literature discussing tolerance stack models (Chase and Parkinson, 1991 Harry and Stewart, 1988 Wu et al., 1988). Shifting and drifting of component distributions has been said to be the chief reason for the apparent disenchantment with statistical tolerancing in manufacturing (Evans, 1975). Modern equipment is frequently composed of thousands of components, all of which interact within various tolerances. Failures often arise from a combination of drift conditions rather than the failure of a specific component. These are more difficult to predict and are therefore less likely to be foreseen by the designer (Smith, 1993). 

If listed toxic chemicals are present equal to or above the de minimis cut-off level, your supplier must identify the specific components as they appear in Table II and provide their percentage composition by weight in the mixture or product, tf your supplier maintains that the identity ot a toxic chemical is a trade secret, a generic identity that is structurally descriptive must be supplied on the notice. A maximum concentration level must be provided if your supplier contends that chemical composition information is a trade secret. In either case, you do not need to make a trade secret claim on behalf of your supplier (unless you consider your use of the proprietary mixture a trade secret). On Form R, identify the toxic chemical you are reporting according to its generic name provided in the notification. (See the instructions for Part III, Section 2 on page 18 for more information.) tf the listed chemical is present below the de minimis level, no notification is required. 

Adsorption, which utilizes the ability of a solid adsorbent to adsorb specific components from a gaseous or a liquid solution onto its surface. Examples of adsorption include the use of granular activated carbon for the removal of ben-zene/toluene/xylene mixtures from underground water, the separation of ketones from aqueous wastes of an oil refinery, aad the recovery of organic solvents from the exhaust gases of polymer manufacturing facilities. Other examples include the use of activated alumina to adsorb fluorides and arsenic from metal-finishing emissions. 

Similarly, the Site B contractor s SSAHP provided corporate policy and procedures for permit-required confined space entry but lacked the site-specific detail necessary to describe the application of the corporate policy to procedures at the site. For example, the SSAHP did not identify specific components of the thermal treatment unit that presented confined space hazards, nor did it describe the specific circumstances or procedures that would require employee entry into these areas. In addition, the plan stated that the contractor would maintain an onsite employee confined space rescue team, but did not identify the members of this team. The SSAHP for Site F also contained a generic confined space entry program but did not identify the specific location of confined space hazards present at the site. 

Level A for Operational Safety Management updates the plant status for specific components that are out of service and forecasts the effect on core melt frequency using minimal cutsets generated in Level B. Code features include ... 

TABLE 9.20 Recommended Maximum Pressure Drops for Specific Components in Supply Air Systems... 

Chapter 9 discusses the refrigeration and cryogenic processes used u-remove specific components from a gas stream, thereby reducing its Btu content. 

Data Summaries of Licensee Event Reports at U.S. Commercial Nuclear Power Plants (Vanous Components) Nuclear 11209 one-fine event descriptions on specific component types failure rates and error factors Pumps, valves, diesels inverters, relays, circuit breakers (in separate reports) 100. 

RAC publications include data summaries for specific component types, such as hybrid microcircuits, small, medium and large-scale integration digital devices, linear and interface devices, digital monolithic devices, and discrete semiconductors. In addition, there are reliability and equipment maintenance data books that provide the failure and repair time data on military electronic equipment by application such as subsystem. 

Appendix III of this report provides a detailed description of the reliability data used in event tree and fault tree quantification. Because of its extensive operating experience and the uniqueness of the BRP design, BRP plant-specific data was used whenever possible. Plant-specific data sources included plant maintenance orders, control room log books, surveillance tests, LERs, event reports, deviation reports, plant review committee meeting minutes, and USNRC correspondence. The plant-specific data used spanned the period from 1970 to 1979. Data before 1970 did not include maintenance orders or surveillance tests and therefore were excluded. The plant-specific data collected for BRP is presented in detail in Appendix XIII. Table III-4 summarizes 30 plant-specific component failure rates and Table 11-06 contains plant-specific maintenance unavailabilities for 20 components. These tables are a summary of the BRP component failure and maintenance outages. 

Opening segments of the IP2 PRA data analysis section describe the definitions of terms and concepts employed, the assumptions made, and limitations recognized during the data base construction. A set of 39 plant-specific component failure mode summaries established the basis for component service hour determinations, the number of failures, and the test data source for each failure mode given for each component. Generic data from WASH-1400, IEEE Std 500, and the LER data summaries on valves, pumps, and diesels were combined with plant-specific failure data to produce "updated" failure information. All the IP2 specialized component hardware failure data, both generic and updated, are contained in Table 1.5.1-4 (IP3 1.6.1-4). This table contains (by system, component, and failure mode) plant-specific data on the number of failures and service hours or demands. For some components, it was determined that specifications of the system was warranted because of its impact on the data values. 

In coupled LC-GC, specific components or classes of components of complex mixtures are pre-fractionated by LC and are then transferred on-line to a GC system for analytical separation. Because of the ease of collecting and handling liquids, off-line LC-GC techniques are very popular, but they do present several disadvantages, e.g. the numerous steps involved, long analysis times, possibility of contamination, etc. The on-line coupled LC-GC techniques avoid all of these disadvantages, thus allowing us to solve difficult analytical problems in a fully automated way. 

K-factors for vapor-liquid equilibrium ratios are usually associated with various hydrocarbons and some common impurities as nitrogen, carbon dioxide, and hydrogen sulfide [48]. The K-factor is the equilibrium ratio of the mole fraction of a component in the vapor phase divided by the mole fraction of the same component in the liquid phase. K is generally considered a function of the mixture composition in which a specific component occurs, plus the temperature and pressure of the system at equilibrium. 

The ratio f/f° is called activity, a. Note This is not the activity coefficient. The activity is an indication of how active a substance is relative to its standard state (not necessarily zero pressure), f°. The standard state is the reference condition, which may be anything however, most references are to constant temperature, with composition and pressure varying as required. Fugacity becomes a corrected pressure, representing a specific component s deviation from ideal. The fugacity coefficient is ... 

L = mols of liquid at a specific temperature and pressure, from F, per unit time i = specific individual component in mixture Kj = equilibrium K values for a specific component at a specific temperature and pressure, from References 18, 65, 79, 99, 131, 235 T = temperature, abs... 

X] = mol fraction of a specific component in liquid mixture as may be associated with feed, distillate, or bottoms, respectively = mol fraction of a specific component in vapor mixture as may be associated with the feed, distillate or bottoms, respectively... 

Constant-speed machinery If a machine-train operates at constant speed, the best method is to set the windows using the Fmin and Fmax frequencies associated with the specific component. For example, a narrowband window could be established to monitor the energy generated... 

Figure 44.27 Narrowband trends provide energy histories of specific components...

In addition to identifying general failure modes that are common to many types of machine-train components, failure-mode analysis can be used to identify failure modes for specific components in a machine-train. However, care must be exercised when analyzing vibration profiles, because the data may reflect induced... 

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