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Dimensional characteristics

We must now mention, that traditionally it is the custom, especially in chemo-metrics, for outliers to have a different definition, and even a different interpretation. Suppose that we have a fc-dimensional characteristic vector, i.e., k different molecular descriptors are used. If we imagine a fe-dimensional hyperspace, then the dataset objects will find different places. Some of them will tend to group together, while others will be allocated to more remote regions. One can by convention define a margin beyond which there starts the realm of strong outliers. "Moderate outliers stay near this margin. [Pg.213]

For cubic crystals, which iaclude sUicon, properties described by other than a zero- or a second-rank tensor are anisotropic (17). Thus, ia principle, whether or not a particular property is anisotropic can be predicted. There are some properties, however, for which the tensor rank is not known. In addition, ia very thin crystal sections, the crystal may have two-dimensional characteristics and exhibit a different symmetry from the bulk, three-dimensional crystal (18). Table 4 is a listing of various isotropic and anisotropic sUicon properties. Table 5 gives values for the more common physical properties and for some of the thermodynamic properties. Figure 5 shows some thermal properties. [Pg.529]

Proc., 65(3), 45 (1986)] is preferred. To use this and alternate models, dimensional characteristics of structured packing must be defined. Figure 14-51 shows nomenclature and definitions of key dimensions. Not shown, but also important, is the angle the corrugations make with the horizontal (usu y 45 or 60°). Then the Rocha et al. predictive equation is ... [Pg.1388]

It can be shown that the right-hand side of Eq. (3-208) is the -dimensional characteristic function of a -dimensional distribution function, and that the -dimensional distribution function of afn, , s n approaches this distribution function. Under suitable additional hypothesis, it can also be shown that the joint probability density function of s , , sjn approaches the joint probability density function whose characteristic function is given by the right-hand side of Eq. (3-208). To preserve the analogy with the one-dimensional case, this distribution (density) function is called the -dimensional, zero mean gaussian distribution (density) function. The explicit form of this density function can be obtained by taking the i-dimensional Fourier transform of e HsA, with the result.45... [Pg.160]

The Gaussian Process.—A gaussian process was defined in the last section to be a process all of whose finite-order distributions are multi-dimensional gaussian distributions. This means that the multi-dimensional characteristic function of Px.fK must be of the form... [Pg.176]

Selected examples of block copolymer micelles in both aqueous and organic media will then be presented in Sects. 3 and 4. Section 4.3 emphasizes stimulus-responsive micellar systems from double-hydrophilic block copolymers. Prediction of the dimensional characteristic features of block copolymer micelles and how it varies with the composition of the copolymers will be shortly outlined in Sect. 5, with a consideration of both the theoretical and experimental approaches. Tuning of micellar morphology and triggering transitions between different morphologies will then be discussed in Sect. 6. [Pg.81]

Other data are not less important initial value of PE-parameter of 2S2-orbital of magnesium atom gives from PE-parameter (table 3) of radical (O-H) a=8.24 % and p 77-82 %. This p value can increase to even 100 % under the light action due to minor changes in dimensional characteristics of atoms-components. Absolute difference of these P-parameters equals 0.43 eV, thus corresponding to the changes in the scale of potentials during the synthesis of ATP. [Pg.96]

The radiation energy hv in PS-1 promotes, apparently, the changes in dimensional characteristics of phosphorous and oxygen atoms from covalent to anion ones. Therefore, P0-parameters of free phosphorus and oxygen atoms are distributed at the distance of their anion radii 1.86 A and 1.40 A, respectively. This similarity of values of their PE-parameters a=5.19 % for 2P3-orbitals of phosphorous with 2P2-orbitals of oxygen (table 3). [Pg.98]

The half of intemuclear distance (for binary bond) of similar atoms or atomic, covalence or ionic radii (depending upon bond type) can be used as a dimensional characteristic of atoms. [Pg.99]

Based on equations (2-5) with initial data calculated with quantum-mechanical techniques [6-8], the values of P0-parameters of the majority of elements being tabulated constant values for each valence atom orbital were calculated. Mainly covalent radii were applied as a dimensional characteristic for calculating PE-parameter - by main type of chemical bond of interactions considered (table 1). For hydrogen atom also the value of Bohr radius and value of atomic ( metal ) radius were applied. [Pg.112]

Let us consider these initial notions as applicable to certain allotropic carbon modifications using dimensional characteristics and values of P-parameters that are given in [8] and table 1. [Pg.209]

And not only the distance between the nearest similar atoms by bond length (d) is the basic dimensional characteristic, but also the distance to geometric center of cycle interacting atoms Of) as the geometric center of total electron density of all hybridized cycle atoms. [Pg.209]

Geometrical considerations about intermetallic crystal structures. When discussing the factors which control the structures of the metallic elements, Laves (1956) proposed three interrelated principles that are mainly geometric in character and also related to the atomic dimensional characteristics ... [Pg.254]

In an effort to understand if HAMs are, in any way, different from LAMs (low activity molecules), we extended this survey to compounds published between 1991 and 2002, as indexed in WOMBAT [26]. This database [27] contains 4927 unique structures with at least one measured activity better than 1 nM (HAMs), and 34028 unique structures with at least one activity less than 1 XM (LAMs). Between HAMs and LAMs, 1080 molecules are common, that is, they have at least one activity above 1 nM and at least one activity below 1 XM. This is not uncommon for, for example, highly selective molecules. We did not exclude these from either set since we monitor trends, not exact figures. We studied these trends using 2-D-(two-dimensional) descriptors, that is, descriptors that do not use information related to the three-dimensional characteristics of model compounds. These descriptors can be classified as follows ... [Pg.29]

Bertrand, R., and H. Pezerat (1980). Fibrous glass carcinogenicity and dimensional characteristics, pp. 901-911. In Wagner, J. C., ed. Biological Effects erf Mineral Fibers. Vol. 2, Pub. No. 30 of International Agency for Research on Cancer, Lyon, France. [Pg.152]

In both their industrial and biological functions, the 3-dimensional characteristics of carbohydrates are important. Many of these stereochemical features are described for carbohydrates in the classic text by Stoddart (2). The inqportance of stereochemistry is underscored by the unique chemical and physical properties of the individual sugars, many of which are configurational isomers. Stereochemistry also plays a role in detentlining the properties of polysaccharides. Molecular shape is as significant for the properties of an industrially modified starch as it is for the recognition of one particular blood type and the rejection of others. [Pg.1]

Ratio of a dimensional characteristic of a macromolecule in a given solvent at a given temperature to the same dimensional characteristic in the theta state at the same temperature. The most frequently used expansion factors are expansion factor of the mean-square end-to-end distance, Ur = (/o) expansion factor of the radius oj gyration, as = (/0) relative viscosity, = ([ /]/[ /]o), where [ ] and [ /]o are the intrinsic viscosity in a given solvent and in the theta state at the same temperature, respectively. [Pg.54]

Note Expansion factors defined by different dimensional characteristics are not exactly equal, nor need they have a constant ratio as a function of relative molecular mass. [Pg.55]

The independence of the limiting characteristic viscosity on the type of solvent means that cpi is independent of the viscosity of the solvent, that is the dimensional characteristic of the internal friction of the macromolecule Cyi is proportional to the viscosity of the solvent and the internal friction is not solely internal. The conclusion that the solvent contributes significantly to the intramolecular viscosity was reported by Schrag (1991), and was dubbed as the solvent modification effect . [Pg.110]

Fig. 11 Nascent radiation initiated PTFE dispersion particles. The polymerization conditions were (a) 0% emulsifier, 90 min, (b) 0.5% emulsifier, 60 min, (c) 1% emulsifier, 60 min, (d) 2% emulsifier, 90 min, all for essentially the same radiation dose rate at 25 °C in water (with 1.3% hexadecane and ammonium perfluorooctanoate emulsifier) at 30-kg/cm2 pressure. The measured molecular weights, the corresponding extended chain lengths (eel) the and dimensional characteristics are, respectively, (a) Mn = 230 x 104, edn = 6.0 pm, particle volume approximately 7 x 108 Da (b) Mn = 50 x 104, eel = 1.3 pm, rod diameter approximately 100 molecules (c) Mn = 20 x 104, ed = 0.52 pm rod length (d) Mn=2xl04, ed = 520A. (Reprinted from Ref. [14] with permission from Wiley-Interscience)... Fig. 11 Nascent radiation initiated PTFE dispersion particles. The polymerization conditions were (a) 0% emulsifier, 90 min, (b) 0.5% emulsifier, 60 min, (c) 1% emulsifier, 60 min, (d) 2% emulsifier, 90 min, all for essentially the same radiation dose rate at 25 °C in water (with 1.3% hexadecane and ammonium perfluorooctanoate emulsifier) at 30-kg/cm2 pressure. The measured molecular weights, the corresponding extended chain lengths (eel) the and dimensional characteristics are, respectively, (a) Mn = 230 x 104, edn = 6.0 pm, particle volume approximately 7 x 108 Da (b) Mn = 50 x 104, eel = 1.3 pm, rod diameter approximately 100 molecules (c) Mn = 20 x 104, ed = 0.52 pm rod length (d) Mn=2xl04, ed = 520A. (Reprinted from Ref. [14] with permission from Wiley-Interscience)...
Figure 6 Reduction of the number of sources of uncertainty through the three-dimensional characteristics of uncertainty (see inset) level of uncertainty, appraisal of the knowledge base and subjectivity of choices... Figure 6 Reduction of the number of sources of uncertainty through the three-dimensional characteristics of uncertainty (see inset) level of uncertainty, appraisal of the knowledge base and subjectivity of choices...
Annex 1 provides a case-study of a qualitative characterization of uncertainties in an exposure assessment. Table A1.2 in Annex 1 details the evaluation throughout the three-dimensional characteristics. Included is an overall conclusion on sensitivity—that is, those aspects that have the most significant impact on the outcome of the assessment, as better data collected on these features would considerably reduce the measure of uncertainty. An example of the overall conclusion is given in section A 1.5 of Annex 1. The main uncertainties identified in the assessment are tabulated, as illustrated in Table 5, and a brief explanation of the weights given to them in reaching an overall conclusion is provided. In addition, a textual description of the qualitative characterization of tabular output should include an indication of overall uncertainty, based on the collective impact of each of the sources. [Pg.46]

The NIOSH method for the analysis of asbestos (9) states that "The method is intended to give an index of employee exposure to airborne asbestos fibers of specified dimensional characteristics. It is not meant to count all asbestos fibers in all size ranges or to differentiate asbestos from other fibrous particulates". [Pg.14]

Opportunity. A three-color concentrate-two-component plastic colorants A, B, and C and components D and E are mixed, then injection molded to form a dimensional product.The customer is pleased with dimensional characteristics but has noted some increased color variance to a more positive DH value in recent lots. While none of the lots has exceed the 0.4 maximum specification, all of the most recent shipment was at or near that tolerance. [Pg.398]

In this brief chapter we have attempted to highlight both the past and the present, and to hint at the future of the study of microbial compounds which we believe will continue to lead to the discovery and development of new and useful products. There is no question that in the past medicine and agriculture have benefited from the wide variety of potent microbial metabolites. The diversity of chemistry that microorganisms are able to exploit has led to large numbers of unique structures with three-dimensional characteristics giving them equally unexpected and unique biological activity recent results have shown that these compounds frequently display multiple activities. [Pg.232]

P0 and PE-parameters of free atoms were calculated based on equations (1, 2), the results of which are given in Table 1. For hydrogen atom the value of Bohr radius of hydrogen atom equaled to 0.529A and besides, for some cases - ionic radius (1.36A) were used as the main dimensional characteristics. [Pg.18]


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Characteristics dimensionality

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