Loading effects

Anonymous, Shock-Loading Effect On, and Deformation Twinning of Beryllium, John Crerar Library, Research Information Service Bib. No. 236, Chicago, IL, 6 pp., June 1967. 

Foundation Loads and Pressures. Foundations should be designed to support the weight of the structure, the live load, and the load effect on the structure and its foundation due to such other loads as v. ind. In general, for foundation designs, a safety factor of 3 is used for dead loads or live loads independently. A safety factor of 2 is used for combination loads including transient loads [38,40]. 

The sliding and loading effect of these gears is such that they generally operate outside the limiting conditions for... 

Figure 1. Principle of the atom-fountain-based gravimeter achieved in S. Chu group at Stanford. The right figure shows a two days recording of the variation of gravity. The accuracy enables to resolve ocean loading effects.

FIGURE 26.21 Coefficient of friction (A) and the temperature rise (B) in the contact area between a natural rubber (NR) gum compound and a thermocouple slider as function of speed at different loads. Also shown are the data when plotted against log a v (C), indicating a rising portion of a single master curve which absorbs also the apparent load effect. 

The reaction sequence of formaldehyde formation and subsequent COad formation can proceed either as sequential reactions of adsorbed species, or it can involve formation and desorption of formaldehyde into the electrol5d e and subsequent re-adsorption and further decomposition of formaldehyde to COad. Considering the significant transport and catalyst loading effects discussed above, it is clear that desorption and subsequent re-adsorption plus dehydrogenation of formaldehyde will play an important role also for COad formation, although a direct reaction of adsorbed RIad species can not be ruled out. 

An explosion results in several structural loading effects, which can produce destmctive consequences to buildings and equipment. These consequences range from minor damage to complete collapse, depending on the structure s ability to withstand the loading effects. Table 5.1 summarizes the structural loadings that result from various explosion effects. 

The susceptibility of hardness measurements of silica and silicate glasses to environmental factors is consistent with the effects of water on the deformation of quartz. The load effect and indentation size effect appear to be a result of the frictional forces at the indenter-specimen interfaces. 

In helping to create a consensus set of guidelines, a number of individual and groups provided valuable assistance and review. These include Ted Krauthammer of Penn State, chairman of ACI committee 370 (Short Duration Dynamic and Vibratory Load Effects), Paul Mlakar of Jaycor, chairman of the ASCE Task Committee on Physical Security, and Quentin Baker of Wilfred Baker Engineering. Reviewers included Brad Otis of Shell Oil Company, Al Wusslcr of El Paso Natural Gas Company, and Eve Hinman of Failure Analysis Associates. 

The plastic hinge nonlinear material model is easier to use but usually can not consider axial load effects. Plastic hinge locations must usually be predetermined and are usually limited to the ends of the member. Analysis results which include displacements and plastic hinge rotations which are directly comparable against acceptance criteria. ... 

An analysis (55) of the loading effect, which has been extended (59) to include multiple etchant loading and other etchant loss processes, indicates that the etch rate (R) for N wafers each of area A is given by... 

In the case of tungsten or copper CMP where alumina slurries are used, the pH of the solution must be greater than 9 or lower than 2 to avoid adhesion of the slurries in the porous structure of the brush (back to Fig. 13). This phenomenon, called the loading effect, increases the final particle levels on the wafers and therefore drastically reduces the brush lifetime. This effect can be greatly attenuated by injection of 0.5 to 2% ammonia, for example. 

The simple scrubber process is very efficient to eliminate slurries but does not remove the metallic contamination or the damaged layer. The simplest additional process is to use an HF-based step which removes both of them. The use of an HF-compatible scrubber saves an additional wet bench with a dryer and a wafer transfer. The chemistries used must avoid loading effects. 

Si02 slurries are quite easy to remove and do not produce any brush-loading effect since the commercial slurry used does not contain too many foreign particles. The simplest scrubber process consists in a... 

The potential activation of different Lewis acid catalysts and their load effect when used in combination with this solvent were explored, in order to determine the improvement of rates and selectivity to the endo and exo isomers. The list of Lewis acid catalysts included Li(OTf), Li(NTf2), Znl2, AICI3, BF3, HOTf, HNTf2, Ce(0Tf)4 5H20, Y(OTf)3, Sc(OTf)3, Sc(NTf2) and a blank without any Lewis acid. The reaction conditions were as follows 2.2 mmol of cyclopentadiene + 2.0 mmol of dienophile + 0.2 mol% of catalyst in 2 mL [hmim][BF4]. When no catalyst was added, the two ketones (R =Me-C=0 R2 = R3 = H and Ri=Et-C=0 R2 = R3 = H) showed modest activity ( 50% in 1 h) with endojexo selectivity = 85/15. Whereas acrolein showed modest activity (59% conversion in 2 h), methacrolein and crotonaldehyde were inert without a Lewis acid catalyst. Acrylonitrile and methyl acrylate underwent low conversions in 1 h (16-17%) whereas, N-phenylmaleimide, maleic anhydride and 2-methyl-1,4-benzoquinone showed complete reaction in 5 min with high endo isomer yields. 

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