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Positional forces

Technically speaking, negative pressures don t exist. Pressure is only a positive force and it is either present or absent. [Pg.7]

Conversely, when A-alkyl tryptophan methyl esters were condensed with aldehydes, the trans diastereomers were observed as the major products." X-ray-crystal structures of 1,2,3-trisubstituted tetrahydro-P-carbolines revealed that the Cl substituent preferentially adopted a pseudo-axial position, forcing the C3 substituent into a pseudo-equatorial orientation to give the kinetically and thermodynamically preferred trans isomer." As the steric size of the Cl and N2 substituents increased, the selectivity for the trans isomer became greater. A-alkyl-L-tryptophan methyl ester 42 was condensed with various aliphatic aldehydes in the presence of trifluoroacetic acid to give predominantly the trans isomers. ... [Pg.474]

Note the initial negative deviation in response to a positive forcing disturbance, caused by the right half plane zero in the transfer function. [Pg.526]

The conservation of momentum in the z direction with positive forces in the +z directions can be written as... [Pg.304]

Simple switches that can be manually activated can be considered a fire alarm device. Models are used which normally require the use of positive force, i.e., to avoid accident and fraudulent trips. Fire alarm switches normally can only be reset by special tools in order to trace the source of the alarm, however sophisticated data reporting systems with addressable data collection may make this requirement obsolete. [Pg.178]

With a phenol, naphthol or keto-enol coupling component the mechanism is given by Scheme 4.4, in which blocking of the p-position forces coupling at the o-position. In certain cases involving the use of feebly reactive diazonium salts, loss of the proton from the transition state (4-1) in Scheme 4.4 may be slow but may often be facilitated by the addition of a tertiary base, such as pyridine, to the coupling mixture [7,8]. [Pg.182]

Thus, the rate of change of momentum is positive and by Newton s law a positive force must act on the fluid in the section, ie a force in the positive x-direction. If the flow were reversed, the force would be reversed. [Pg.21]

An alternative substrate design, in which the alkene radical cation is substituted only at the internal position, forces the nucleophilic cyclization into the endocyclic mode, leading overall to bicyclic systems with a bridgehead nitrogen (Scheme 31) [139,140]. [Pg.38]

The electronic display will show a small positive force that remains because of the wetting of the vertical support of the ring. [Pg.635]

The most common parameters derived from the TPA curve are shown in Table H2.3.1 (Friedman et al., 1963 Bourne, 1968). The peak force during the first compression cycle is defined as hardness. Fracturability (originally called brittleness) is defined as the force at the first significant break in the curve during the first compression cycle. The ratio of the positive force area during the second compression cycle to that during the first compression... [Pg.1187]

Background. The term microsensor denotes a transducer that, in some fashion, exploits advanced miniaturization technology, whether an adaptation of integrated circuit technology, or some other microfabrication technique. Within the past decade, a myriad of microsensors have been developed, with capabilities for measurement of temperature, pressure, flow, position, force, acceleration, chemical reactions, and the concentrations of chemical species. The latter measurements, of chemical species, are intrinsically more difficult than the measurement of mechanical variables because in addition to requirements of accuracy, stability, and sensitivity, there is a requirement for specificity. [Pg.166]

Standard 4 This standard demands a sense of humor—an ability to laugh at where you are, to see yourself in perspective. To qualify, individuals must consistently make a special effort to see the positive lighter side of life and communicate it to others. If you are considered good company, you probably have met this standard. If known as a positive force, you qualify. If you consistently make others laugh, you re setting a standard. [Pg.54]

Standard 10 This standard requires you to remain a positive force within the community as long as possible. You must continue to have an impact on others through speaking up and taking action when appropriate. Others must sense your presence. In certain situations, it may mean becoming a matriarch or patriarch within a family circle. Master Seniors are strong personalities. [Pg.56]

The force resisting extension for an ideal rubber is completely entropically derived. Because it certainly requires a positive force to stretch a rubber,... [Pg.125]

Prof. Chuiko was a positive force in many people s lives. He is remembered as an outstanding and talented scientist, a man of deep erudition possessing a sharp and ever active mind. He was a man of inexhaustible energy, initiative, and wisdom. His sincere generosity will remain in the hearts of his colleagues. [Pg.450]


See other pages where Positional forces is mentioned: [Pg.342]    [Pg.345]    [Pg.210]    [Pg.260]    [Pg.106]    [Pg.471]    [Pg.351]    [Pg.37]    [Pg.254]    [Pg.280]    [Pg.787]    [Pg.787]    [Pg.787]    [Pg.788]    [Pg.796]    [Pg.796]    [Pg.204]    [Pg.13]    [Pg.290]    [Pg.40]    [Pg.386]    [Pg.39]    [Pg.242]    [Pg.244]    [Pg.1188]    [Pg.527]    [Pg.77]    [Pg.78]    [Pg.80]    [Pg.278]    [Pg.599]    [Pg.33]    [Pg.96]    [Pg.310]    [Pg.52]   
See also in sourсe #XX -- [ Pg.196 ]




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