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Dimension tables

To eliminate the ambiguities in the subject of electricity and magnetism, it is convenient to add charge q to the traditional I, m and t dimensions of mechanics to form the reference dimensions. In many situations permittivity S or permeabiUty ]1 is used in Heu of charge. For thermal problems temperature Tis considered as a reference dimension. Tables 2 and 3 Hst the exponents of dimensions of some common variables in the fields of electromagnetism and heat. [Pg.104]

Examination of the chemical composition of cells reveals a dazzling variety of organic compounds covering a wide range of molecular dimensions (Table 1.2). As this complexity is sorted out and biomolecules are classified according to the similarities in size and chemical properties, an organizational pat-... [Pg.9]

A fundamental idea in multivariate data analysis is to regard the distance between objects in the variable space as a measure of the similarity of the objects. Distance and similarity are inverse a large distance means a low similarity. Two objects are considered to belong to the same category or to have similar properties if their distance is small. The distance between objects depends on the selected distance definition, the used variables, and on the scaling of the variables. Distance measurements in high-dimensional space are extensions of distance measures in two dimensions (Table 2.3). [Pg.58]

Table 2 shows the most important secondary dimensions. Table 3 refers to some very frequently used secondary units that have been named after famous researchers. [Pg.4]

Crystallite dimensions. Crystallite dimensions plays a role in determining the rates of reactions, and their control is of fundamental importance not only for the catalytic activity, but also for the selectivity, since with low rates of the desired reaction, the relative importance of secondary reactions may be greater. The effects of crystallite dimensions have been demonstrated for 1-butene epoxida-tion (Clerici et al., 1993) and for phenol hydroxylation (van der Pol et al., 1993), and they are significant for many reactions carried with liquid phase reactants. The results obtained for phenol hydroxylation with samples of different dimensions (Table II) are useful to clarify this point. [Pg.294]

As can be seen, the magnitude of the observed peak or limiting current is dependent upon the value of D, which is a function of the solvent medium, the molecular weight of the electroactive species, the temperature, the electrolyte and the molecular dimensions. Table 2 shows typical values of D under a range of conditions. [Pg.18]

Dimension Tables. In a data mart or warehouse, the dimension tables store non-redun-dant information about the entries in the fact table of the database. For the chemical example of an inventory data mart, the fact table stores the various source database identifiers cf each unique structure in the data mart. A dimension table of molecular formulas would store the formula for the unique structure in the mart, rather than storing the same formula for each occurrence of that structure in the various source databases. [Pg.403]

Fact Table. A central table in a data warehouse whose rows each represent one unit of primary importance in the warehouse. In a chemical warehouse, the rows of the fact table might correspond to unique structures in the database. In a biology data warehouse, each row might correspond to a single experiment. The fields in the fact table are mainly pointers to information stored in other tables, or they contain data that may be repeated in other tables but is stored in the fact table (i.e., denormal ized) for rapid access. The fact table connects to other "dimension" tables in the warehouse that contain specific information that is not duplicated. [Pg.404]

Star Schema. A standard data warehouse architecture, characterized by Ralph Kimball, in which a central "fact" table is connected to various "dimension" tables. [Pg.410]

Let US examine the effect of dirt type first. A large number of explosive tests as well as a series of very near surface nuclear shots have been condueted on very different types of geology. From these experiments, statistical values for cratering efficiency, Eqk, as a function of geological type were determined. The efficiency, cr, is related to crater volume. This same number can be used in relation to radius as well as depth in the form cr > since the volume of a crater is roughly proportional to the cube of its linear dimensions. Table 29.1 gives cr values for various geological materials. [Pg.426]

The acrylamide concentration is chosen for the first dimension (acid gel), and may be 10% for fractionation of RNA mixtures containing maximum chain lengths of about 80 nucleotides (as applied by De Wachter and Fiers to a typical viral RNA partial digest), and is then made twice as high in the second (neutral) gel. The concentration of cross-linker (Bis) is 1/30 that of acrylamide. The buffer in reservoir and gel is 0.025 M citric acid, 6 M urea for the first dimension, and 0.04 M Tris-citric acid, pH 8, for the second dimension. Table 8.3 summarises the concentrations and amounts of stock solutions conveniently used for the preparation of each gel, as well as the catalyst, which is added iimnediately before the gel is poured. [Pg.403]

If such a calculation is carried out for a real three-dimensional crystal, the result is a series (such as that just given in brackets) whose value sums to a dimensionless number that depends upon the crystal structure. That number is called the Madelung constant, M, and its value is independent of the unitcell dimensions. Table 21.5 lists the values of the Madelung constant for several crystal structures. The lattice energy is again the opposite of the total potential energy. Expressed in terms of the Madelung constant, it is... [Pg.883]

In two studies of Am metal the he form was found but with rather different densities and cell dimensions (Table 29.4). Although the less dense form was not reproduced in the later study it is conceivable that there are two forms of the metal with the same structure, as in the case of Ce. In the case of Cm also the he structure reported earlier was not found in a later study here the difference between the densities of two (close-packed) forms is more than a little surprising. [Pg.1020]

The channel system in zeolites can be 1-, 2-, or 3-dimensional that is, the channels extend along one, two, three-dimensions. Table 2.6 lists the channel dimensions of zeolites ordered by decreasing number of T-atoms in the largest rings.[4] Interconnecting channel systems are separated by a double arrow (<- ). A vertical bar ( ) means that there is no direct access from one channel system to the other. A perpendicular symbol ( ) represents a direction that is perpendicular to a crystallographic plane. The number of asterisks ( ) indicates the dimensions of the channel system, e.g. 1-, 2-, or 3-dimension. A few examples are selected from Table 2.6 to illustrate the notation for crystallographic characterization of the channels. [Pg.43]

Dimensional homogeneity is fundamental to equations relating variables in the description of natural processes. The recognition of this basic attribute is the substance of dimensional analysis, which results in the reduction of relevant parameters to the essential minimum. Physical quantities comprise combinations of one or more basic dimensions. Table 2.2 shows some commonly used physical quantities in engineering expressed in terms of basic dimensions (mass, M length, L time, T, temperature, 0). [Pg.78]

The ammonium salt, NH4HY, crystallizes in the same system as RbHY, with almost identical cell dimensions (Table 14), but it gives some weak reflexions that systematically infringe the condition for C-centring and show that this crystal must belong to a different space group, Pmaa. [Pg.174]

Many applications of hydrogels need a patterned layer on a substrate. Different techniques were used for patterning in different regions of dimension (Table 2). [Pg.46]

In the case of the 5T%g) term the orbital kets are the same as for the 2T2(g) term. A higher spin multiplicity enlarges the dimension of the interaction matrix to N = 3-5=15. The secular equation can be split into a set of secular equations of lower dimension (Table 8.40). The zero-field energy levels are shown in Fig. 8.23. [Pg.498]

X-ray diffraction suggested that the (rather poor) crystals of the 1 2 TNT and TNB (1,3,5-trinitrobenzene) adducts were actually jt-charge transfer compounds but that the other adducts were inclusion compounds. Determination of cell dimensions (Table 8) and comparison of Debye-Scherrer photographs suggested that the latter could be grouped as follows ... [Pg.132]

The gt 06 position was previously mled out because of short contacts that occur when the chains are rotated Into the 61-63 positions that give the best R factors (Table VI). The questioned interaction Is within the sheets, where the chain centers are spaced apart by about 8.2 A (the unit cell b dimension). Table X shows that the chains need only be rotated 2 from the positions of lowest R in order to provide sufficient (>2.6 A) clearance. The historic Meyer-Mlsch cell has a dimension of 8.35 A, providing even more clearance. Therefore, the unit cell dimensions are critical to such determinations. [Pg.33]

Since the second hyperpolarizability is involved in the equation, symmetrical molecules of the D-A-D type and A-D-A type are suitable, but also donor-substituted porphyrins, in which charge transfer may occur in two dimensions. Table 14.8 briefly summarises MPE cross sections of some reported dyes. Some of the special dyes synthesised for very large MPE effects are presented in Fig. 14.31. As can be observed from the data, there is a reasonably good correlation between the observed and calculated excitation and cross section data. The increase in length gave the most substantial increase in the 2PE cross section and in excitation wavelength. [Pg.658]

It has been recently shown (65) that the balance between the two functions is catalyst, as well as feedstock dependent. When zeolites are used as the acidic component, the large pore 12 MR structures, are the most suitable ones, since in these type of structures long chain branched alkanes can diffuse. Moreover, not all 12 MR zeolites behave in the same way for hydroisomerization and the final results also depend on the geometry and the pore dimensions (Table 8). [Pg.392]

Due to the lack of existing commercial models for double flank roll testers applied to micro gears verification, a functional blocks design of the machine adapted to the selected micro gear dimensions (Table 1) is accomplished in this work. [Pg.47]


See other pages where Dimension tables is mentioned: [Pg.221]    [Pg.696]    [Pg.108]    [Pg.398]    [Pg.126]    [Pg.4]    [Pg.188]    [Pg.75]    [Pg.373]    [Pg.519]    [Pg.361]    [Pg.390]    [Pg.402]    [Pg.226]    [Pg.419]    [Pg.349]    [Pg.734]    [Pg.238]    [Pg.497]    [Pg.173]    [Pg.540]    [Pg.372]    [Pg.93]    [Pg.510]    [Pg.522]   
See also in sourсe #XX -- [ Pg.390 , Pg.403 ]

See also in sourсe #XX -- [ Pg.390 , Pg.403 ]




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