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An act that reveals weakness of the will sins against the normative principle that one should not intentionally perform an action when one judges on the basis of what one deems to be all the available considerations that an alternative and accessible course of action would be better.2 This principle, which I call the Principle of Continence, enjoins a fundamental kind of consistency in thought, intention, evaluation and action. An agent who acts in accordance with this principle has the virtue of continence. It is not clear whether a person could fail to recognize the norm of continence this is an issue to which 1 shall turn presently. In any case, it is clear that there are many people who accept the norm but fail from time to time to act in accordance with it. In such cases, not only do agents fail to conform their actions to their own principles, but they also fail to reason as they think they should. For their intentional action shows they have set a higher value on the act they perform than their principles and their reasons say they should. [Pg.81]

The chemical industry is one of the major income generators for Britain, and its products are one of our major exports. It is because the country needs to educate everyone on chemical matters, and also to prepare people on foundation and access courses for future university science courses involving some chemistry that the Royal Society of Chemistry has initiated this and other books. [Pg.5]

One observes that it lies in the more accessible course in both the d-mannose and o-galactose series indeed, its parent octoses are known (n-manno-L-manno-octose and D-gala-L-giafa-octose) and its preparation from the two series seems feasible. [Pg.31]

Access courses, e.g. literacy, numeracy, IT, English, NVQs, apprenticeships, GCSEs, A-Levels, university... [Pg.162]

Progress in the theoretical description of reaction rates in solution of course correlates strongly with that in other theoretical disciplines, in particular those which have profited most from the enonnous advances in computing power such as quantum chemistry and equilibrium as well as non-equilibrium statistical mechanics of liquid solutions where Monte Carlo and molecular dynamics simulations in many cases have taken on the traditional role of experunents, as they allow the detailed investigation of the influence of intra- and intemiolecular potential parameters on the microscopic dynamics not accessible to measurements in the laboratory. No attempt, however, will be made here to address these areas in more than a cursory way, and the interested reader is referred to the corresponding chapters of the encyclopedia. [Pg.832]

The operation of the STM depends on the conduction of electrons between tip and sample. This means, of course, that insulating samples are, in general, not accessible to STM investigations. Nevertheless, a large body of work [32] dealing with STM characterization of thin organic films on conducting substrates is now in... [Pg.1682]

The objective of chemoinformatics is to assist the chemist in giving access to reaction information, in deriving knowledge on chemical reactions, in predicting the course and outcome of chemical reactions, and in designing syntheses. Specifically, the problems of accomplishing the following tasks have to be solved ... [Pg.170]

The National Cancer Institute (NCI) database is a collection of more than half a million structures, assembled by NCI s Developmental Therapeutics Program (DTP) or its predecessors in the course of NCTs anti-cancer screening efforts that started in the late 1950s (plus the more recent anti-HIV screening) [37-39]. Approximately half of this database is publicly available without any usage restrictions, and is therefore called the "Open NCI Database. For each of these structures (more than 250 000) the DTP record contains at least the chemical structure as a coimection table and an NCI accession number, the NSC number. [Pg.262]

Any errors that remain are of course my own responsibility. If you do find any, I would like to know 1 will also be pleased to receive any constructive suggestions, comments or criticisms. We plan to set up a web site that will provide access to various material from the book (such as electronic versions of the colour images) together with email contacts. This cem be accessed via www.booksites.net. [Pg.17]

A particularly useful property of the PX monomer is its enthalpy of formation. Conventional means of obtaining this value, such as through its heat of combustion, are, of course, excluded by its reactivity. An experimental attempt was made to obtain this measure of chemical reactivity with the help of ion cyclotron resonance a value of 209 17 kJ/mol (50 4 kcal/mol) was obtained (10). Unfortunately, the technique suffers from lack of resolution in addition to experimental imprecision. It is perhaps better to rely on molecular orbital calculations for the formation enthalpy. Using a semiempirical molecular orbital technique, which is tuned to give good values for heat of formation on experimentally accessible compounds, the heat of formation of /5-xylylene has been computed to be 234.8 kj/mol (56.1 kcal/mol) (11). [Pg.429]

Of course, moving the Hquid feed and withdrawal positions continuously is impractical. However, approximately the same effect can be produced by providing multiple Hquid-access lines to the bed and periodically switching each stream to the adjacent line. Functionally, the adsorbent bed has no top or bottom and is equivalent to an aimular bed. Therefore, the four Hquid-access positions can be moved around the bed continually, always maintaining the same distance between the various streams. [Pg.296]

Access to cell rooms is usually restricted to authori2ed personnel. Required personal safety equipment includes mbber shoes or overshoes, goggles, hard hat, and some sort of emergency respirator. Safety training courses are generally required before one is allowed to enter a cell house without a guide. [Pg.82]

A variety of 1-azirines are available (40-90%) from the thermally induced extrusion (>100 °C) of triphenylphosphine oxide from oxazaphospholines (388) (or their acyclic betaine equivalents), which are accessible through 1,3-dipolar cycloaddition of nitrile oxides (389) to alkylidenephosphoranes (390) (66AG(E)1039). Frequently, the isomeric ketenimines (391) are isolated as by-products. The presence of electron withdrawing functionality in either or both of the addition components can influence the course of the reaction. For example, addition of benzonitrile oxide to the phosphorane ester (390 = C02Et) at... [Pg.89]

The fact that the parties acknowledge that in the course of performing work they may have access to or acquire information that is confidential and proprietary. [Pg.40]

Si 2p line, at about 100 eV BE, is also easily accessible at most synchrotron sources but cannot, of course, be observed using He I and He II radiation. On the other hand, the Zn 3d and Hg 4f lines can be observed quite readily by He I radiation (see Table 1) and the elements identified in this way. Quantitative analysis using relative peak intensities is performed exactly as in XPS, but the photoionization cross sections a are very different at UPS photon energies, compared to A1 Ka energies, and tabulated or calculated values are not so readily available. Quantitation, therefore, usually has to be done using local standards. [Pg.305]

In general conclusion, the HMO and SCF methods both appear able to make reasonably accurate predictions about the stabilization in conjugated moleeules. The stabilization is general for benzenoid compounds but quite restricted in nonbenzenoid systems. Because the HMO method of estimating stabiUty is based on the ideas of HMO theory, its general success vindicates the ability of this very simplified MO approach to provide insight into the structural nature of the aimulenes and other conjugated polyenes. More sophisticated MO methods, of course, are now accessible and should be applied for more detailed analysis of the structures of these molecules. [Pg.540]

The electrostatic potential map of benzene conveys the molecule s size as well as its charge distribution in a much more compact manner. The size and shape of the map are, of course, identical to that of the electron density surface, and indicate what part of the molecule is easily accessible to other molecules (the outside world ). The colors reveal... [Pg.30]

Conditions more accessible to rate measurements and, possibly, more favorable to a normal course of substitution (Section II, A) make the use of activated compounds such as nitro- and aza-sub-stituted derivatives desirable. In both cases, the activated halogeno-substituted five-membered ring heterocycle is also more reactive than a similarly activated six-membered ring compound. This... [Pg.348]

This reaction, which is named after W. Williamson, is the most important method for the synthesis of unsymmetrical ethers 3. For this purpose an alkoxide or phenoxide 1 is reacted with an alkyl halide 2 (with R = alkyl, allyl or benzyl). Symmetrical ethers can of course also be prepared by this route, but are accessible by other routes as well. [Pg.291]

The total syntheses of penicillin and cephalosporin represent elegant tours de force that demonstrated once again the power of synthetic organic chemistry. These syntheses, however, had little effect on the course of drug development in the respective fields, since they failed to provide access to analogs that could not be prepared by modification of either the side chains or, as in the case of more recent work, modification of 6-APA and 7-ACA themselves. In order to have an impact on drug development, a total synthesis must provide means for preparing... [Pg.418]

Clearly, there are horses for courses . The practicing plant engineer may have access to a local specialist in certain types of non-destructive testing who provides an excellent service and value for money. At the same time, the plant engineer must be vigilant regarding the limitations of such support. [Pg.142]

Section 1.9 showed that as long as an oxide layer remains adherent and continuous it can be expected to increase in thickness in conformity with one of a number of possible rate laws. This qualification of continuity is most important the direct access of oxidant to the metal by way of pores and cracks inevitably means an increase in oxidation rate, and often in a manner in which the lower rate is not regained. In common with other phase change reactions the volume of the solid phase alters during the course of oxidation it is the manner in which this change is accommodated which frequently determines whether the oxide will develop discontinuities. It is found, for example, that oxidation behaviour depends not only on time and temperature but also on specimen geometry, oxide strength and plasticity or even on specific environmental interactions such as volatilisation or dissolution. [Pg.268]


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See also in sourсe #XX -- [ Pg.4 ]




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