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Similar effects

however, we look at the second divided difference scheme 2((1 + z2)/2)2, we find a more complicated story. [Pg.135]

the polygons are shown as lines and the limit points, using an appropriate unit row eigenvector, as dots. We see that the limit points do what we expect, but the polygon shows no sign of converging towards them. [Pg.135]

It does not actually diverge, in the way that a scheme with a high norm might be expected to, but its behaviour is uncomfortable. [Pg.135]

This effect is not, of course, limited to schemes generating B-splines. [-1,1,7,9,9,7,1,-1]/16 [Pg.135]

Nor is it limited to factors of the form (1 + z2 ). Any factor which is a function of only even powers of z has a similar property. [Pg.135]


The AET was used at standard tests of numerous structural materials, above all steels and cast iron, prepared are ceramic samples. Part of tested samples had qjecial sur ce layer treatments by laser, plasma nitridation and similar. Effect of special surface treatment the authors published already earlier [5,6]. In this contribution are summed up typical courses of basic dependencies, measured by the AET at contact loading. [Pg.63]

Finally, similar effects can be seen in miscible polymer blends where the surface tension correlates with the enrichment of the lower-energy component at the surface as monitored by x-ray photoelectron spectroscopy [104],... [Pg.71]

Spectral lines are fiirther broadened by collisions. To a first approximation, collisions can be drought of as just reducing the lifetime of the excited state. For example, collisions of molecules will connnonly change the rotational state. That will reduce the lifetime of a given state. Even if die state is not changed, the collision will cause a phase shift in the light wave being absorbed or emitted and that will have a similar effect. The line shapes of collisionally broadened lines are similar to the natural line shape of equation (B1.1.20) with a lifetime related to the mean time between collisions. The details will depend on the nature of the intemrolecular forces. We will not pursue the subject fiirther here. [Pg.1144]

The model consists of a two dimensional harmonic oscillator with mass 1 and force constants of 1 and 25. In Fig. 1 we show trajectories of the two oscillators computed with two time steps. When the time step is sufficiently small compared to the period of the fast oscillator an essentially exact result is obtained. If the time step is large then only the slow vibration persists, and is quite accurate. The filtering effect is consistent (of course) with our analytical analysis. Similar effects were demonstrated for more complex systems [7]. [Pg.278]

This work already showed that substituent constants of one reaction can only be transferred to another reaction when similar effects are operating and when they are operating to the same extent. In order to find a broader basis for the transfer-ability of substituent constants, they were split into substituent constants for the resonance effect and those for the inductive effect. [Pg.182]

In view of the remarkable effects that water can exert on the uncatalysed Diels-Alder reaction, there might well be a similar effect on the rate and the selectivity of the Lewis-acid catalysed process. At the same time, coordination of a Lewis-acid to a Diels-Alder reagent is likely to overcome the... [Pg.31]

A similar effect is obtained by using the spin-constrained UHF method (SUHF). In this method, the spin contamination error in a UHF wave function is constrained by the use of a Lagrangian multiplier. This removes the spin contamination completely as the multiplier goes to infinity. In practice, small positive values remove most of the spin contamination. [Pg.229]

The state of aqueous solutions of nitric acid In strongly acidic solutions water is a weaker base than its behaviour in dilute solutions would predict, for it is almost unprotonated in concentrated nitric acid, and only partially protonated in concentrated sulphuric acid. The addition of water to nitric acid affects the equilibrium leading to the formation of the nitronium and nitrate ions ( 2.2.1). The intensity of the peak in the Raman spectrum associated with the nitronium ion decreases with the progressive addition of water, and the peak is absent from the spectrum of solutions containing more than about 5% of water a similar effect has been observed in the infra-red spectrum. ... [Pg.7]

For the methyl-substituted compounds (322) the increase in AG and AHf values relative to the unsubstituted thiazole is interpreted as being mainly due to polar effects. Electron-donating methyl groups are expected to stabilize the thiazolium ion, that is to decrease its acid strength. From Table 1-51 it may be seen that there is an increase in AG and AH by about 1 kcal mole for each methyl group. Similar effects have been observed for picolines and lutidines (325). [Pg.93]

Four-ring ketones ca 1780 have a similar effect on these values as on those of open-chain ketones. [Pg.740]

In the laboratory, it has been found that similar effects can be produced if a voltage is applied between two electrodes immersed in a gas. The nature of the laboratory or instrumental discharge depends critically on the type of gas used, the gas pressure, and the magnitude of the applied voltage. The actual electrical and gas pressure conditions determine whether or not the discharge is called a corona, a plasma, or an arc. [Pg.29]

Synergists. The effect of antimony oxide on the flammabiUty of unsaturated polyesters that contain chlorine is shown in Table 11. A similar effect on the flammabiUty of unsaturated polyester containing 2inc stannates and bromine instead of chlorine is given in Table 12. [Pg.461]

Entrance andExit SpanXireas. The thermal design methods presented assume that the temperature of the sheUside fluid at the entrance end of aU tubes is uniform and the same as the inlet temperature, except for cross-flow heat exchangers. This phenomenon results from the one-dimensional analysis method used in the development of the design equations. In reaUty, the temperature of the sheUside fluid away from the bundle entrance is different from the inlet temperature because heat transfer takes place between the sheUside and tubeside fluids, as the sheUside fluid flows over the tubes to reach the region away from the bundle entrance in the entrance span of the tube bundle. A similar effect takes place in the exit span of the tube bundle (12). [Pg.489]

A similar effect occurs in highly chiral nematic Hquid crystals. In a narrow temperature range (seldom wider than 1°C) between the chiral nematic phase and the isotropic Hquid phase, up to three phases are stable in which a cubic lattice of defects (where the director is not defined) exist in a compHcated, orientationaHy ordered twisted stmcture (11). Again, the introduction of these defects allows the bulk of the Hquid crystal to adopt a chiral stmcture which is energetically more favorable than both the chiral nematic and isotropic phases. The distance between defects is hundreds of nanometers, so these phases reflect light just as crystals reflect x-rays. They are called the blue phases because the first phases of this type observed reflected light in the blue part of the spectmm. The arrangement of defects possesses body-centered cubic symmetry for one blue phase, simple cubic symmetry for another blue phase, and seems to be amorphous for a third blue phase. [Pg.194]

Process variables also play a significant part in determination of surface finish. For example, the higher the current density, generally the smoother the finish on the workpiece surface. Tests using nickel machined in HCl solution show that the surface finish improves from an etched to a poHshed appearance when the current density is increased from ca 8 to 19 A/cm and the flow velocity is held constant. A similar effect is achieved when the electrolyte velocity is increased. Bright smooth finishes are obtained over the main machining zone using both NaCl and NaNO electrolyte solutions and current densities of 45-75 A/cm. ... [Pg.309]

Fluorine. Fluoride is present in the bones and teeth in very small quantities. Human ingestion is from 0.7—3.4 mg/d from food and water. Evidence for the essentiaUty of fluorine was obtained by maintaining rats on a duoride-free diet, resulting in decreased growth rate, decreased fertihty, and anemia. These impairments were remedied by supplementing the diets with duoride (81). Similar effects have been reported in goats (82). [Pg.384]

Liver Effects. In 1980 a 2-year feeding study carried out as part of the NTP/NCI Bioassay Program in the United States (38,39) indicated that DEHP causes increased incidence of Hver tumors in rats and mice and that DEHA had a similar effect in mice but not rats. In these studies the levels of plasticizers fed were very high, this being possible only because of thek low acute toxicity. [Pg.130]

One component of the age-ielated decline in immune function is decreased production of the lymphokine that promotes the growth of T-ceUs, interleukin 2 (IL-2). Administration of recombinant-derived IL-2, both in vitro and in vivo, appears to restore certain immune functions in aged mice. Recovery of T-regulatory effects on B-ceU differentiation has been reported in human cells from elderly patients treated with IL-1 and/or IL-2 (42). Similar effects have been observed in the presence of the pentapeptide thymopentin [69558-55-0] (Arg Lys Asp Val Tyr), a weU-known IL-2 inducer. Recombinant IL-2 adrninistered to aged mice for three weeks has been shown to correct the T-ceU functional deficiency associated with antigen-specific immunoglobulin production by certain lymphoid tissue (43). [Pg.431]

N-ethyl kanamycin A (153) has some resistance to APH(3 ), ANT(2 ), and AAC(3). Butakacin [59733-86-7] C22H N 0 2 t i l-A/-(3)-2-hydroxy-4-aminobutyl derivative of kanamycin A (154), has antimicrobial properties similar to amikacin. A similar effect was seen with the l-A/-(l,3-dihydroxy-2-propyl) derivative of kanamycin B, propikacin [66887-96-5] C22H42N 022 (155). Methylation of the 6 -amine reduces susceptibility to AAC(6 ) (156). [Pg.484]

In order to obtain a homogenous and stable latex compound, it is necessary that insoluble additives be reduced in particle size to an optimum of ca 5 )Tm and dispersed or emulsified in water. Larger-size chemical particles form a nucleus for agglomeration of smaller particles and cause localized dispersion instabiHty particles <3 fim tend to cluster with similar effect, and over-milled zinc oxide dispersions are particularly prone to this. Water-soluble ingredients, including some accelerators, can be added directly to the latex but should be made at dilute strength and at similar pH value to that of the latex concentrate. [Pg.252]

Sorbic acid is not only suitable for preservation of feedstuffs but also improves the feed utilisation and weight gain of chickens. This has proven to be of economic value under practical conditions when sorbic acid is added to the feed at 0.02—0.04 wt % (143—145). Similar effects have been observed for the use of sorbic acid in swine feeds (146). [Pg.287]

The cyclopropenoid fatty acids, malvaUc acid and stercuhc acid, exist in hexane-defatted meal at levels of 21—76 ppm (70). In rainbow trout, the cyclopropenoid acids cause cancer of the fiver either alone or by acting synergistically with aflatoxin B. However, similar effects in mammals or humans have not been demonstrated (63). [Pg.301]


See other pages where Similar effects is mentioned: [Pg.546]    [Pg.1449]    [Pg.1524]    [Pg.2377]    [Pg.384]    [Pg.166]    [Pg.192]    [Pg.19]    [Pg.1149]    [Pg.582]    [Pg.137]    [Pg.191]    [Pg.165]    [Pg.201]    [Pg.331]    [Pg.312]    [Pg.222]    [Pg.184]    [Pg.349]    [Pg.380]    [Pg.102]    [Pg.269]    [Pg.260]    [Pg.483]    [Pg.484]    [Pg.515]    [Pg.502]    [Pg.6]   


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