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Prescribing principles

Good Laboratory Practice In response to concerns in the mid-1970s about the veracity of reports on the safety of clinical medicines, the US FDA issued regulations in 1978 to prescribe principles of GLP... [Pg.3982]

General hydrodynamic theory for liquid penetrant testing (PT) has been worked out in [1], Basic principles of the theory were described in details in [2,3], This theory enables, for example, to calculate the minimum crack s width that can be detected by prescribed product family (penetrant, excess penetrant remover and developer), when dry powder is used as the developer. One needs for that such characteristics as surface tension of penetrant a and some characteristics of developer s layer, thickness h, effective radius of pores and porosity TI. One more characteristic is the residual depth of defect s filling with penetrant before the application of a developer. The methods for experimental determination of these characteristics were worked out in [4]. [Pg.613]

Our first three chapters established some fundamental principles concerning the structure of organic molecules and introduced the connection between structure and reactivity with a review of acid-base reactions In this chapter we explore structure and reactivity m more detail by developing two concepts functional groups and reaction mechanisms A functional group is the atom or group m a molecule most respon sible for the reaction the compound undergoes under a prescribed set of conditions How the structure of the reactant is transformed to that of the product is what we mean by the reaction mechanism... [Pg.142]

The subject matter of quality objectives is prescribed by the quality policy to some extent. Hence an appropriate method would be to derive one or more statements of objectives from each statement in the quality policy. If you adopt the eight quality management principles as your framework, having eight groups of quality objectives would not be unreasonable (see previously under Subject matter for quality policy). [Pg.105]

Object in this section is to review how rheological knowledge combined with laboratory data can be used to predict stresses developed in plastics undergoing strains at different rates and at different temperatures. The procedure of using laboratory experimental data for the prediction of mechanical behavior under a prescribed use condition involves two principles that are familiar to rheologists one is Boltzmann s superposition principle which enables one to utilize basic experimental data such as a stress relaxation modulus in predicting stresses under any strain history the other is the principle of reduced variables which by a temperature-log time shift allows the time scale of such a prediction to be extended substantially beyond the limits of the time scale of the original experiment. [Pg.41]

Subcase b2 This case, called the paired f-test , is often done when two test procedures, such as methods A and B, are applied to the same samples, for instance when validating a proposed procedure with respect to the accepted one. In practicular, an official content uniformity" 5 assay might prescribe a photometric measurement (extract the active principle from a tablet... [Pg.49]

The main goal of any approximate method is to solve an original (continnons) problem with a prescribed accuracy e > 0 in a finite number of operations. In order to clarify whether it is possible in principle to approximate a solution u of problem (35)-(36) by a solntion j/ , of problem (37) with any prescribed accuracy e > 0 depending on the step h[e), we follow established practice. This is concerned with further comparison of with u x) in the space of grid functions Hh. Let be a value of the function u x) on the grid u>i, so that Hh- The error of... [Pg.78]

The above example shows that although the scheme with cr = 1 is absolutely stable and, in principle, may be used for any r, it is not accurate enough at the stage of the regular behavior when t grows. In order to retain a prescribed accuracy (here it is meaninful to speak only about the relative accuracy), we should refine successively the step r = Tj with increasing tj. So, we are much disappointed by the main advantage of the scheme with 7=1 stipulated by its stability for any r > 0. [Pg.332]

Stability theory is quite applicable to formulate a general principle for regularizing difference schemes in order to obtain stable schemes of a prescribed quality. [Pg.782]

The basic principles are described in many textbooks [24, 26]. They are thus only sketchily presented here. In a conventional classical molecular dynamics calculation, a system of particles is placed within a cell of fixed volume, most frequently cubic in size. A set of velocities is also assigned, usually drawn from a Maxwell-Boltzmann distribution appropriate to the temperature of interest and selected in a way so as to make the net linear momentum zero. The subsequent trajectories of the particles are then calculated using the Newton equations of motion. Employing the finite difference method, this set of differential equations is transformed into a set of algebraic equations, which are solved by computer. The particles are assumed to interact through some prescribed force law. The dispersion, dipole-dipole, and polarization forces are typically included whenever possible, they are taken from the literature. [Pg.271]

The guiding principles in test plot maintenance are to (1) minimize soil surface disturbance at all times, (2) ensure that control and treated plots are similarly maintained, (3) avoid applying other agrochemicals that may interfere with sample analysis or that are otherwise contrary to the purpose of the study, (4) follow the prescribed irrigation policy determined for the study site, and (5) keep bare-soil test plots free of vegetation, as follows. [Pg.871]

Become familiar with the pharmacokinetic and pharmacodynamic principles of medications prescribed in ICU patients... [Pg.65]

C. C. Fuselier, General principles of drug prescribing, in Pharmacy Practice for the Geriatric Patient (F. B. Penta, et al., eds.), American Association of Colleges of Pharmacy, Alexandria, VA, 1985, pp. 8.1-8.28. [Pg.690]

What made evolution flow might also have proved contentious had Darwin not also oiled his way around problems of mechanism. Darwin s sixth edition of Origin ultimately accommodated evolution to Lamarck s principle of psychic anamnesis and the inheritance of acquired characteristics, the laws of nature as prescribed by a deity, and God s eternal wisdom. Darwin only hoped that natural selection would be seen to play some part somewhere along the way of descent with modification . [Pg.88]

Although pharmacology usually plays a critical role in drug development, the principles of pharmacology are less often followed in the practice of medical therapeutics, which is often performed by using predetermined or empiric prescribing patterns. Clinically there is often a broader set of rela-... [Pg.105]

The inclusion of radiative heat transfer effects can be accommodated by the stagnant layer model. However, this can only be done if a priori we can prescribe or calculate these effects. The complications of radiative heat transfer in flames is illustrated in Figure 9.12. This illustration is only schematic and does not represent the spectral and continuum effects fully. A more complete overview on radiative heat transfer in flame can be found in Tien, Lee and Stretton [12]. In Figure 9.12, the heat fluxes are presented as incident (to a sensor at T,, ) and absorbed (at TV) at the surface. Any attempt to discriminate further for the radiant heating would prove tedious and pedantic. It should be clear from heat transfer principles that we have effects of surface and gas phase radiative emittance, reflectance, absorptance and transmittance. These are complicated by the spectral character of the radiation, the soot and combustion product temperature and concentration distributions, and the decomposition of the surface. Reasonable approximations that serve to simplify are ... [Pg.255]

Three different principles govern the design of bench-scale calorimetric units heat flow, heat balance, and power consumption. The RC1 [184], for example, is based on the heat-flow principle, by measuring the temperature difference between the reaction mixture and the heat transfer fluid in the reactor jacket. In order to determine the heat release rate, the heat transfer coefficient and area must be known. The Contalab [185], as originally marketed by Contraves, is based on the heat balance principle, by measuring the difference between the temperature of the heat transfer fluid at the jacket inlet and the outlet. Knowledge of the characteristics of the heat transfer fluid, such as mass flow rates and the specific heat, is required. ThermoMetric instruments, such as the CPA [188], are designed on the power compensation principle (i.e., the supply or removal of heat to or from the reactor vessel to maintain reactor contents at a prescribed temperature is measured). [Pg.117]

The AMFC Directive requires that food control laboratories should be accredited to the EN 45000 series of standards as supplemented by some of the OECD GLP principles. In the UK, government departments have nominated the United Kingdom Accreditation Service (UKAS) to carry out the accreditation of official food control laboratories for all the aspects prescribed in the Directive. However, as the accreditation agency will also be required to comply with the EN 45003 Standard and to carry out assessments in accordance with the EN 45002 Standard, all accreditation agencies that are members of the European Cooperation for Accreditation of Laboratories (EA) may be asked to carry out the accreditation of a food control laboratory within the UK. Similar procedures will be followed in the other Member States, all having or developing equivalent organisations to UKAS. Details of the UK requirements for food control laboratories are described later in this chapter. [Pg.81]


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See also in sourсe #XX -- [ Pg.111 ]




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