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Shortened multiplication

The latest trend is to smaller beads in smaller columns, as this saves eluent and shortens the time for a chromatographic analysis. This argument can be correct if only one suitable detector is used. However, these modern small columns are not optimal for a combination of detectors. So-called multiple detection is a combination of some detectors with different measurement principles (differential refractometer, spectral photometer, light-scattering detector, on-line viscometer) behind the last column, mostly in series, seldom in a branched ( parallel ) order. In this way, the tedious preparative fractionation of a polymer sample can often be avoided. [Pg.440]

In addition, when installing multiple belts, it is imperative that the slack side of each belt be on the same side, either top or bottom. Tables 58.2 and 58.3 show the minimum movement below and above the standard center distance required between the pulleys. This movement allows the center distance to be shortened for new belt installation. It also allows the center distance to be increased to take up the slack and to maintain proper tension as the belt stretches (Figure 58.6). [Pg.974]

Although blood pressure control follows Ohm s law and seems to be simple, it underlies a complex circuit of interrelated systems. Hence, numerous physiologic systems that have pleiotropic effects and interact in complex fashion have been found to modulate blood pressure. Because of their number and complexity it is beyond the scope of the current account to cover all mechanisms and feedback circuits involved in blood pressure control. Rather, an overview of the clinically most relevant ones is presented. These systems include the heart, the blood vessels, the extracellular volume, the kidneys, the nervous system, a variety of humoral factors, and molecular events at the cellular level. They are intertwined to maintain adequate tissue perfusion and nutrition. Normal blood pressure control can be related to cardiac output and the total peripheral resistance. The stroke volume and the heart rate determine cardiac output. Each cycle of cardiac contraction propels a bolus of about 70 ml blood into the systemic arterial system. As one example of the interaction of these multiple systems, the stroke volume is dependent in part on intravascular volume regulated by the kidneys as well as on myocardial contractility. The latter is, in turn, a complex function involving sympathetic and parasympathetic control of heart rate intrinsic activity of the cardiac conduction system complex membrane transport and cellular events requiring influx of calcium, which lead to myocardial fibre shortening and relaxation and affects the humoral substances (e.g., catecholamines) in stimulation heart rate and myocardial fibre tension. [Pg.273]

Compared to the sum of covalent radii, metal-silicon single bonds are significantly shortened. This phenomenon is explained by a partial multiple bonding between the metal and silicon [62]. A comparison of several metal complexes throughout the periodic table shows that the largest effects occur with the heaviest metals. However, conclusions drawn concerning the thermodynamic stability of the respective M —Si bonds should be considered with some reservation [146], since in most cases the compared metals show neither the same coordination geometries nor the same oxidation states. [Pg.21]

American co net lower, black susans) angustifolia shortens symptoms and duration of upper respiratory Infections (URIs) including colds mild gastrointestinal (Gl) upsets individuals with autoimmune diseases such as tuberculosis, collagenosis, multiple sclerosis, AIDS and HIV infection. [Pg.659]

There is considerable multiple character in the carbene carbon-X(Y) bonds. An internal comparison of carbon-X(Y) bond lengths in each of the structures tabulated reveals a substantial shortening of carbene car-bon-X(Y) relative to other carbon-X(Y) bonds in the molecule. Carbene carbon-nitrogen distances are found to be shorter in the mono-N-substituted carbenes than in the bis-N-substituted compounds. [Pg.146]

The glass transition temperature is generally measured- by experiments that correspond to a time scale of seconds or minutes. If the experiments are done more rapidly, so that the time scale is shortened, the apparent Tg value is raised. If the time scale is lengthened to hours or days, the apparent Tg value is lowered. Thus, as generally measured, Tg is not a hue constant but shifts with the time scale of the experiment or observation. Moreover, Tg is masked by experimental difficulties, compounded by multiple and often inaccurate definitions of Tg in the literature. The least... [Pg.16]

The data given in Table 13.3 show that the extent of bond shortening is greatest for B-F bonds. This is to be expected because back donation of electron density from F to B is more effective when the donor and acceptor atoms are of comparable size. The following resonance structures are used to represent the multiple bonding between B and F ... [Pg.425]

The minimum amount of information needed to specify a crystal structure is the unit cell type, that is, cubic, tetragonal, and so on, the unit cell parameters, and the positions of all of the atoms in the unit cell. The atomic contents of the unit cell are a simple multiple, Z, of the composition of the material. The value of Z is equal to the number of formula units of the solid in the unit cell. Atom positions are expressed in terms of three coordinates, x, y, and z. These are taken as fractions of a, b, and c, the unit cell sides, say and j. The x, y, and z coordinates are plotted with respect to the unit cell axes, not to a Cartesian set of axes. The space group describes the symmetry of the unit cell, and although it is not mandatory when specifying a structure, its use considerably shortens the list of atomic positions that must be specified in order to built the structure. [Pg.452]


See other pages where Shortened multiplication is mentioned: [Pg.275]    [Pg.275]    [Pg.61]    [Pg.2827]    [Pg.830]    [Pg.21]    [Pg.234]    [Pg.194]    [Pg.82]    [Pg.34]    [Pg.27]    [Pg.63]    [Pg.83]    [Pg.1165]    [Pg.147]    [Pg.69]    [Pg.12]    [Pg.58]    [Pg.61]    [Pg.126]    [Pg.214]    [Pg.215]    [Pg.285]    [Pg.450]    [Pg.15]    [Pg.426]    [Pg.114]    [Pg.301]    [Pg.444]    [Pg.329]    [Pg.114]    [Pg.426]    [Pg.244]    [Pg.279]    [Pg.103]    [Pg.201]    [Pg.267]    [Pg.234]    [Pg.235]    [Pg.472]    [Pg.384]    [Pg.243]    [Pg.229]   
See also in sourсe #XX -- [ Pg.275 ]




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