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Addition auxiliary

If additional, auxiliary constraints are present that are not part of the reaction coordinate (e.g., constraints on covalent bond lengths), the formulas are much more complicated, and the algebra becomes rapidly prohibitive. The same is true when qisa. multidimensional coordinate (e.g., a set of dihedrals). Umbrella sampling approaches (discussed in previous sections) are vastly simpler in such cases and appear to be the method of choice for all but the simplest reaction coordinates. [Pg.188]

The bulk of enamine studies since Stork s original publication have focused on establishing the breadth and limitations of individual substitution reactions and on extending the list of useful electrophiles. In addition, auxiliary studies have enriched our knowledge about the ambident nature of the vinyl nitrogen system, stereoelectronic factors governing its reactivity, its stability and spectroscopic properties. An increasing number of synthetic applications of these fundamental studies can be expected in future years. [Pg.314]

In practice, production processes are usually rather more complex. Raw materials are usually impure and thus some pre-purification steps may be required. Obviously impurities in the raw materials will incresae the probability of impurities and byproducts occuring in the output stream from the chemical conversion step. Even using pure raw materials, most chemical conversion are incomplete and often lead to the formation of undesirable byproducts. Furthermore often additional (auxiliary) materials are used (for example catalysts, specific solvents), which have to be separated from the desired product. Thus, in typical production processes a large number of separation steps are required. [Pg.5]

To minimize damage due to power outage, the Celanese Corporation in their plant at Newark, N.J., instituted a policy of always generating half its own power. Merck Company installed additional auxiliary steam power to insure constant refrigeration for its biochemicals at its West Point, Pa., plant. At Allied Chemical s phenol plant in Frankfort, Pa., electric devices on air compressors and pumps were replaced by steam-operated controls, and diesel generators were installed to maintain cooling water circulation. 19... [Pg.41]

The plasma torch is usually mounted on a circular end wall. The torch is aligned in such a way that waste material falls into the hot zone of the plasma arc. The torch cathode and anode are cooled by forced water flow. In addition, auxiliary cooling of the anode with air can be incorporated in the plasma torch. [Pg.163]

Note that the vector i// is not an orbital vector, but rather a vector of length 4, and i//"1, i//"2 are taken to represent elements of different vectors. We can interpret i// as a variational object associated with the occupancy of orbital i, for example, i// 1 is associated with the occupancy of the first orbital, i// 2 with the occupancy of the second, etc. The above product ansatz contains only 4k parameters and is certainly very tractable. However, it is also not, in general, very accurate So, let us try to improve the ansatz by increasing the flexibility of the vectors i//. We can introduce additional auxiliary indices, making each vector into a tensor, that is... [Pg.151]

Fig. 2.9 shows the main directory structure and the structure of two subdirectories of the NMR data base stored on your CD-ROM as displayed by the WINDOWS File manager. If it is planned to copy the NMR data from your CD-ROM onto your hard disk to speed up further processing, the same directory structure should be established there (see 2.5.5). Note, however, that ID WIN-NMR generates additional auxiliary subdirectories (AU, DAT, NMR, PC, TMP) in the directory DEMOID on your harddisk. [Pg.20]

Richardson, P. J., Mizuguchi, K., Jackson, A. P. Beta3 an additional auxiliary subunit of the voltage-sensitive sodium channel that modulates channels gating with distinct kinetics, Proc. Natl. Acad. Sci. USA 2000, 97, 2308-2313. [Pg.328]

In the H2O-VUV AOP no additional auxiliary oxidants must be used to produce sufficient amounts of OH radicals. The technical development of incoherent exci-mer VUV and UV sources of electromagnetic radiation (see Chapter 4.3) led to a renaissance of research related to water photolysis. Hence, the experimental conditions and results of several recent investigations that deal with the applications of VUV and UV incoherent excimer lamps in the field of AOP research (mainly in aqueous media) are briefly summarized in Tab. 7-2. [Pg.201]

Plant Addition Auxiliary Facilities Grass-Roots Plant 0.17 0.08 0.52 0.07... [Pg.65]

The SILIGEN types are additives, auxiliaries for producing special effects in textile finishing, or softening agents that resist heat. [Pg.93]

Although the focus of this review is on selenium, it is necessary to use data on a number of other species during the evaluation process that lead to the recommended data. These so-called auxiliary data are taken both from the publication of CODATA Key Values [89COX/WAG] and from the evaluation of additional auxiliary data in the volume on uranium [92GRE/FUG] and the succeeding volumes noted in Section I.l,... [Pg.3]

This chapter presents the chemical thermodynamic data for auxiliary compounds and complexes which are used within the NEA s TDB project. Most of these auxiliary species are used in the evaluation of the recommended selenium data in Table lll-l, Table II1-2, and Table III-3. It is therefore essential to always use these auxiliary data in conjunction with the selected data for selenium. The use of other auxiliary data can lead to inconsistencies and erroneous results. Additional auxiliary data used in this review are found in Appendix E, Table E-2 cf. Section II.7). [Pg.67]

Table A-62 Calculation of the enthalpy of formation of Sc2(SeO3)3-10H2O(am) with additional auxiliary data. The sources of the data are indicated. Table A-62 Calculation of the enthalpy of formation of Sc2(SeO3)3-10H2O(am) with additional auxiliary data. The sources of the data are indicated.
Sc2(SeO3)3 10H2O(am) with additional auxiliary data.499... [Pg.893]

Equations 15 to 25 demonstrate a versatile approach to the phenomenological modeling. Ohen and Civan (74) present, additional, auxiliary relationships that make this model deterministic. In all there are 12 parameters (kl9 k2,. . . , (directly measured by experiment, some are evaluated through sensibility tests, and the rest are determined by history matching experimental results with simulations. [Pg.355]

GAM/BUG] and [2005OLI/NOL]), and their use is recommended by this review. Zirconium forms compounds with many of the elements of the Periodic Table. The sources of auxiliary data mentioned do not eontain all data that were needed. Additional auxiliary data were obtained from the literature and, when used, the source has been indicated in Chapter VI. Recalculation of data is presented in Appendix A and, where necessary, the re-evaluation has involved new auxiliary data when needed. Care has been taken that all the selected thermodynamic data at standard conditions are internally consistent. For this purpose, special software has been developed at the NEA Data Bank that is operated in conjunction with the NEA-TDB data base system, cf. Section II.6. To maintain consistency in the application of the values selected by this review, it is essential to use these auxiliary data. [Pg.5]


See other pages where Addition auxiliary is mentioned: [Pg.171]    [Pg.368]    [Pg.695]    [Pg.21]    [Pg.180]    [Pg.347]    [Pg.67]    [Pg.535]    [Pg.181]    [Pg.233]    [Pg.6]    [Pg.107]    [Pg.157]    [Pg.555]    [Pg.73]    [Pg.129]    [Pg.560]    [Pg.245]    [Pg.203]    [Pg.4]    [Pg.355]    [Pg.407]    [Pg.106]    [Pg.491]    [Pg.334]    [Pg.141]    [Pg.5]   


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1,4-addition auxiliary-controlled

Additions to Imine Derivatives Bearing N-Bound Auxiliaries

Auxiliary additives

Auxiliary-Based Conjugate Additions

Chiral auxiliaries Conjugate addition with

Chiral auxiliaries Michael addition

Chiral auxiliaries enantioselective Michael addition

Chiral auxiliaries imine additions

Chiral auxiliaries nitron addition

Chiral auxiliaries, diastereoselectivity, asymmetric Michael additions

Chiral auxiliaries, nucleophilic addition

Chiral auxiliary aldol addition reactions

Conjugate additions chiral auxiliaries

Michael addition, with chiral auxiliaries

Nucleophilic addition reactions chiral auxiliaries

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