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Standing, general

Provided the diffusion coefficient, D, is not dependent upon composition and position, analytical solutions can be found to give an expression for c in terms of x. (The symbol D generally stands for Dseif, D, or D%, depending upon the experimental details.)... [Pg.476]

Arturo Schwarz called this object the epitome of a basic paradox doors, in general, stand for a fundamental ambiguity, a synthesis of arrivals... [Pg.327]

The boiling point, refractive index, and density of the olefin derivative of any paraffin were shown, by use of Table III, to stand in the onier of their olefin type. Table X contains the engine data of the olefin derivatives of 2-methylpentane and 3-methylpentane, recorded in the order of their olefin type. No consistent relations between octane numbers or critical compression ratios are obvious—but the blending octane numbers of these branched olefins, as measured by both the research and Motor methods, do generally stand in the order of their type. Two olefins of type III form exceptions, the exceptions being in one case too high and in the other case too low. [Pg.367]

EXTENSIONS AND COMMENT ARY Here is another example of the presentation of a compound for which there has not yet been an effective level determined. Why For a very good reason. This is an example of a whole class of compounds that I have called the pseudos, or the -compounds. Pseudo- as a prefix in the literary world generally stands for false. A pseudopod is a thing that looks like a foot, but isn t one. A pseudonym is a fictitious name. But in chemistry, it has quite a different meaning. If something has a common name, and there is a second form (or isomer, or shape, or orientation) that is possible and it doesn t have a common name, it can be given the name of the first form with a pseudo- attached. Ephedrine is the erythro-isomer of N-methyl-13-hydroxyamphetamine. There is a second stereoisomer, the threo- isomer, but it has no trivial name. So it is called pseudoephedrine, or the Sudafed of sinus decongestant fame. [Pg.59]

Here. .. depends on the W-kernels introduced above, but in general stands for terms of the form cross-section, appropriately weighted by factors [1 — cosl(0)], l = 1, 2,. .., if the efficiency of exchange of quantity A in a collision depends on the scattering angle 0 in this way (as, e.g., in case of elastic neutral particle - ion collisions, see Sect. 2.2.4). In case of inelastic collision processes a is simply the total cross-section, denoted weighting exponent l = 1, 2,... is possible) or a1. In principle the detector functions qa must be obtained by numerical integration and tabulated for the parameters of the relevant distribution functions fa. [Pg.44]

European Commission, Health Consumer Protection Directorate-General, Standing Committee on the Food Chain and Animal Health. [Pg.456]

This chapter reviews revision ACL reconstruction using conventional BPTB graft via a round tunnel and focuses on where this technique generally stands in the current situation of revision ACL reconstruction. In addition, our preferred procedure of one-stage revision is described with a representative case of post-synthetic ligament failure associated with a large bone defect in the femur. [Pg.470]

Here Tjv denotes the nuclear kinetic energy, V(Q) is the diagonal matrix containing the adiabatic potential energy surfaces Vi(Q) and 1 generally stands for the unit matrix in electronic function space. The vector x(Q) collects the vibrational wavefunctions Xi(Q) of interest, and the elements Aij of the nonadiabatic coupling matrix A can be written as ... [Pg.178]

C-D frequencies generally stand in the ratio of about 1 1.35 to the corresponding CH frequencies, the ratio being slightly higher than 1 V2, which would be predicted for D and H bound to an infinitely heavy atom. [Pg.128]

Chemical stability. The chemical stability of SA films is of interest in many areas. However, tliere is no general mle for it. The chemical stability of silane films is remarkable, due to tlieir intennolecular crosslinking. Therefore, tliey are found to be more stable tlian LB films. Alkyltrichlorosilane monolayers provide stmctures tliat are stable to chemical conditions tliat most LB films could not stand. However, photopolymerized LB films also show considerable stability in organic solvents. [Pg.2626]

In our introductory remarks, we said that this section would be devoted to model systems. Nevertheless it is important to emphasize that although this case is treated within a group of model systems this model stands for the general case of a two-state sub-Hilbert space. Moreover, this is the only case for which we can show, analytically, for a nonmodel system, that the restrictions on the D matrix indeed lead to a quantization of the relevant non-adiabatic coupling term. [Pg.654]

Tn general, the. solvent-accessible surface (SAS) represents a specific class of surfaces, including the Connolly surface. Specifically, the SAS stands for a quite discrete model of a surface, which is based on the work of Lee and Richards [182. They were interested in the interactions between protein and solvent molecules that determine the hydrophobicity and the folding of the proteins. In order to obtain the surface of the molecule, which the solvent can access, a probe sphere rolls over the van der Waals surface (equivalent to the Connolly surface). The trace of the center of the probe sphere determines the solvent-accessible surjace, often called the accessible swface or the Lee and Richards surface (Figure 2-120). Simultaneously, the trajectory generated between the probe and the van der Waals surface is defined as the molecular or Connolly surface. [Pg.127]

General operating WIN WIN WIN WIN stand- Unix Java-soft- olua-in WIN WIN ... [Pg.151]

All glassware should be scrupulously clean and, for most purposes, dry before being employed in preparative work in the laboratory. It is well to develop the habit of cleaning all glass apparatus immediately after use the nature of the dirt will, in general, be known at the time, and, furthermore, the cleaning process becomes more difficult if the dirty apparatus is allowed to stand for any considerable period, particularly if volatile solvents have evaporated in the meantime. [Pg.53]

For temperatures up to 100°, a water bath or steam bath is generally employed. The simplest form is a beaker or an enamelled iron vessel mounted on a suitable stand water is placed in the vessel, which is heated by means of a flame. This arrangement may be used for non-inflammable liquids or for refluxing liquids of low boiling point. Since numerous liquids of low boiling point are highly inflammable, the presence of a naked flame will introduce considerable risk of fire. For such liquids a steam bath or an electrically-heated water bath, provided with a constant-level device, must be used. If the laboratory is equipped with a... [Pg.57]

In general, however, satisfactory separation will be obtained if the mixture is allowed to stand for some time. [Pg.151]

Method 2 (from the free amine). Dissolve 9 - 3 g. (9 1 ml.) of aniline in 10 ml. of glacial acetic acid diluted to 100 ml. contained in a 250 ml. beaker or conical flask, and add with stirring or shaking a solution of 6 5 g. of pure sodium cyanate in 50 ml. of warm water. Allow to stand for 30 minutes, then cool in ice, and allow to stand for a further 30 minutes. Filter at the pump, wash with water and dry in the steam oven. The resulting phenylurea is generally colourless and has a m.p. of 148° (i.e., is pure) the yield is 11 g. If the colour or the m.p. of the product is not quite satisfactory, recrj stallise it from boiling water (10 ml. per gram) as in Method 1. [Pg.645]

Allow a mixture of 0-5 g. of the tertiary amine and 0-5 ml. of colourless methyl iodide to stand for 5 minutes. If reaction has not occurred, warm under reflux for 5 minutes on a water bath and then cool in ice water. The mixture will generally set solid if it does not, scratch the sides of the tube with a glass rod. RecrystaUise the solid product from absolute alcohol, ethyl acetate, acetone, glacial acetic acid or alcohol-ether. [Pg.660]

Nicotinamide. Place 50 g. of pure ethyl nicotinate (Section V,23) in a 350 ml. bolt-head flask and add 75 ml. of concentrated aqueous ammonia saturated at 0°. Keep the flask loosely stoppered for 18 hours, after w)iich time the lower layer generally dissolves on shaking. Saturate the solution with ammonia and allow it to stand for a further 4 hours. Repeat the saturation with ammonia crystals of the amide commence to appear in the solution. Evaporate to drjmess in a dish on the steam bath and dry at 120°. The yield of nicotinamide, m.p. 130°, is usuallj quantitative. [Pg.850]

Recovery of the wopropyl alcohol. It is not usually economical to recover the isopropyl alcohol because of its lo v cost. However, if the alcohol is to be recovered, great care must be exercised particularly if it has been allowed to stand for several days peroxides are readily formed in the impure acetone - isopropyl alcohol mixtures. Test first for peroxides by adding 0-6 ml. of the isopropyl alcohol to 1 ml. of 10 per cent, potassium iodide solution acidified with 0-6 ml. of dilute (1 5) hydrochloric acid and mixed with a few drops of starch solution if a blue (or blue-black) coloration appears in one minute, the test is positive. One convenient method of removing the peroxides is to reflux each one litre of recovered isopropyl alcohol with 10-15 g. of solid stannous chloride for half an hour. Test for peroxides with a portion of the cooled solution if iodine is liberated, add further 5 g. portions of stannous chloride followed by refluxing for half-hour periods until the test is negative. Then add about 200 g. of quicklime, reflux for 4 hours, and distil (Fig. II, 47, 2) discard the first portion of the distillate until the test for acetone is negative (Crotyl Alcohol, Note 1). Peroxides generally redevelop in tliis purified isopropyl alcohol in several days. [Pg.886]

GAMESS stands for general atomic and molecular electronic structure system (we reviewed a version dated Dec. 2, 1998). It is an ah initio and semiempirical program, and has seen the most widespread use for ah initio calculations. The ASCII input hie format is usable but somewhat more lengthy than some other programs. The fact that GAMESS is a free, high-quality software makes it a favorite of many academic researchers. [Pg.335]

A different reaction takes place when electrophiles react with arenes Substitution is observed instead of addition If we represent an arene by the general formula ArH where Ar stands for an aryl group the electrophihc portion of the reagent replaces one of the hydrogens on the ring... [Pg.473]


See other pages where Standing, general is mentioned: [Pg.88]    [Pg.447]    [Pg.88]    [Pg.581]    [Pg.199]    [Pg.125]    [Pg.127]    [Pg.581]    [Pg.324]    [Pg.172]    [Pg.498]    [Pg.415]    [Pg.158]    [Pg.300]    [Pg.127]    [Pg.88]    [Pg.447]    [Pg.88]    [Pg.581]    [Pg.199]    [Pg.125]    [Pg.127]    [Pg.581]    [Pg.324]    [Pg.172]    [Pg.498]    [Pg.415]    [Pg.158]    [Pg.300]    [Pg.127]    [Pg.25]    [Pg.2224]    [Pg.522]    [Pg.561]    [Pg.666]    [Pg.204]    [Pg.62]    [Pg.236]    [Pg.678]    [Pg.863]    [Pg.176]    [Pg.235]    [Pg.161]   
See also in sourсe #XX -- [ Pg.127 ]




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