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Under specific methods

In CZE, separations are controlled by differences in the relative electrophoretic mobilities of the individual components in the sample or test solution. The mobility differences are functions of analyte charge and size under specific method conditions. They are optimized by appropriate control of the composition of the buffer, its pH, and its ionic strength. [Pg.167]

Large quantities of butane are shipped under contract standards rather than under national or worldwide specifications. Most of the petrochemical feedstock materials are sold at purity specifications of 95—99.5 mol %. Butane and butane—petroleum mixtures intended for fuel use are sold worldwide under specifications defined by the Gas Processors Association, and the specifications and test methods have been pubHshed (28). Butanes may be readily detected by gas chromatography. Butanes commonly are stored in caverns (29) or refrigerated tanks. [Pg.403]

Melt Index or Melt Viscosity. Melt index describes the flow behavior of a polymer at a specific temperature under specific pressure. If the melt index is low, its melt viscosity or melt flow resistance is high the latter is a term that denotes the resistance of molten polymer to flow when making film, pipe, or containers. ASTM D1238 is the designated method for this test. [Pg.372]

Degradable plastic is a plastic designed to undergo a significant change in its chemical stmcture under specific environmental conditions, resulting in a loss of some properties that may vary as measured by standard test methods appropriate to the plastic and the appHcation in a particular period of time that determines its classification. [Pg.472]

Phenol Coefficient Test. The first important attempt at standardizing testing methods was known as the phenol coefficient test (96). It has been modified several times, and is an official AO AC screening test recognized by EPA and PDA. The phenol coefficient test compares the activity of disinfectants to that of phenol, under specific conditions, to give a number that measures the activity of the chemical tested with respect to that of phenol, ie, the phenol coefficient. The AO AC method employs visual examination of bacterial growth in a nutrient medium. The Kelsey-Sykes test (1969) is a modified method popular in British circles. [Pg.138]

Having described the underlying philosophy of the traditional approach to accident prevention, we shall now discuss some of the specific methods that are used to implement it, namely motivational campaigns and disciplinary action and consider the evidence for their success. We shall also discuss another frequently employed strategy, the use of safety audits. [Pg.49]

Reproducing the exact solution for the relevant n-electron problem a method ought to yield the same results as the exact solution to the Schrodinger equation to the greatest extent possible. What this means specifically depends on the theory underlying the method. Thus, Hartree-Fock theory should be (and is) able to reproduce the exact solution to the one electron problem, meaning it should be able to treat cases like HeH ... [Pg.8]

Whatever the method finally chosen for the required determination, it should ideally be a specific method that is to say, it should be capable of measuring the amount of desired substance accurately, no matter what other substances may be present. In practice few analytical procedures attain this ideal, but many methods are selective in other words, they can be used to determine any of a small group of ions in the presence of certain specified ions. In many instances the desired selectivity is achieved by carrying out the procedure under carefully controlled conditions, particularly with reference to the pH of the solution. [Pg.12]

Assay Methods. A Na carbonate fusion prod is currently used for assay of mil grade AP (see below under Specifications), but recently attempts have been made to replace it with a method which is faster and simpler to carry out. Two procs have been proposed a) Titanous Chloride Titration. A measured excess of Ti trichloride is added to a known weight of AP which reacts according to the equation ... [Pg.625]

The most commonly used methods for detn of the particle size distribution of fine AP are the Micromerograph and Turbidometric Methods. For coarser AP samples standard sieves are used (see below under Specifications)... [Pg.626]

Karl Fischer Method. See below under Specifications... [Pg.626]

Polyethylene terephthalate (PET) is one of the most important commercial thermoplastic polyesters, which has been on the market since 1977 and is widely used in both industrial and household applications. Under specific conditions, plastics can be converted into their primary components for use in other chemical processes by chemical recycling. PET is a thermoplastic, and so recycling by chemical methods, which converts it into primary components, can be achieved. This study examines the optimal routes of the existing chemical methods. For chemical recycling, acidic hydrolysis is used and PET is converted into terephthalic acid (TPA) and... [Pg.42]

Some drugs will emit light under specific reaction conditions. The discovery of these direct chemiluminescent reactions has come about through trial and error. Table 3 lists some of these drugs and the method used for analysis. Other drugs that are not themselves chemiluminescent can be easily analyzed using a chemiluminescent system (Table 4). [Pg.118]

The distribution coefficient approach - commonly referred to as the K approach - is the most widely applied method in environmental geochemistry for predicting the sorption of contaminant species onto sediments. The distribution coefficient Kd itself is simply the ratio under specific conditions of the sorbed to the dissolved mass of a contaminant. Sorbed and dissolved mass are expressed in units such as... [Pg.137]

The qualification being that it must fail safe not only in its normal mode of operation, but, also, under specific modes of failure. Therefore, it is not enough to state that the circuit is of low voltage, and because of this is intrinsically safe. This is only half of the requirement. To qualify as intrinsically safe, the circuit must also fail in such a way as to be incapable of causing ignition, and further, it must be either tested or analyzed according to prescribe methods. [Pg.257]

Nondestructive hyphenated methods of analysis require follow-on spectro-photometric methods. The most common spectrophotometric analysis is FTIR, and it is most commonly associated with GC. It is, however, possible to combine it with other separation methods under specific conditions. [Pg.330]

In this section, we introduce the model Hamiltonian pertaining to the molecular systems under consideration. As is well known, a curve-crossing problem can be formulated in the adiabatic as well as in a diabatic electronic representation. Depending on the system under consideration and on the specific method used, both representations have been employed in mixed quantum-classical approaches. While the diabatic representation is advantageous to model potential-energy surfaces in the vicinity of an intersection and has been used in mean-field type approaches, other mixed quantum-classical approaches such as the surfacehopping method usually employ the adiabatic representation. [Pg.250]

An air quality model is a method of relating air quality to emission under specific environmental conditions. There are many types of air quality models, and the purposes of this chapter are to describe models that are available for the analysis of photochemical oxidants and to give some information on how well the models perform. [Pg.196]


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Method specificity

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