Cold programming

As discussed in Chapter 3, pseudo-plastic deformation is the key for cold-programmed thermosetting SMP to display shape memory functionality. Therefore, the deformation includes both plastic/viscoplastic and elastic/viscoelastic deformation. The thermomechanical cycle also includes thermal deformation. Based on Figure 4.5, the deformation gradient F can be multiplicatively decomposed into thermal Fj and mechanical Fm, which are further decomposed into plastic F and elastic F, as follows ... 

As the result of many years of nuclear reactor research and development and weapons production in U.S. defense programs, a large number of sites were contarninated by radioactive materials. A thorough cleanup of this residue of the Cold War is expected to extend well into the twenty-first century and cost many billions of dollars. New technologies are needed to minimi2e the cost of the cleanup operation. 

Weapons materials from production reactors were accumulated during the Cold War period as a part of the U.S. defense program. Prominent were tritium, ie, hydrogen-3, having a of 12.3 yr, and plutonium-239, 1/2 = 2.4 X lO" yr. The latter constitutes a waste both as a by-product of weapons fabrication in a waste material called transuranic waste (TRU), and as an excess fissionable material if not used for power production in a reactor. 

C. A. Spindt, Development Program on a Cold Cathode Electron Gun, NASA CR 159570, Stanford Research Institute, Menlo Park, Calif., 1979, pp. 37-38. 

Measurement of Residual Stress and Strain. The displacement of the 2 -value of a particular line in a diffraction pattern from its nominal, nonstressed position gives a measure of the amount of stress retained in the crystaUites during the crystallization process. Thus metals prepared in certain ways (eg, cold rolling) have stress in their polycrystalline form. Strain is a function of peak width, but the peak shape is different than that due to crystaUite size. Usually the two properties, crystaUite size and strain, are deterrnined together by a computer program. 

J. P. E. M. Rijks and J. A. Rijks, Programmed cold sample intr oduction and multidimensional preparative capillary gas cliromatogr aphy. Part I introduction, design and operation of a new mass flow contr olled multidimensional GC system , J. High Resolut. Chromatogr. 13 261 -266 (1990). 

The required warm-up time will vary with ambient conditions, being longer in cold weather and least in warm. Optimum-start controllers are now in general use which are programmed for the building warm-up characteristics and sense the inside and ambient conditions. They then transduce the required start-up period and set the heating plant going only when needed. This, and the previous scheme, will save fuel. 

Sulfates in surface MU water sources usually are present at lower concentrations (typically 20-60 ppm) but this level may rise to several hundred ppm in subsurface waters. The maximum solubility of calcium sulfate is dependent on temperature but is in the range of 1,800 to 2,000 ppm in cold water. This rate is significantly less in hot BW where boiler deposits occur, the sulfate scale normally is present as anhydrite (CaS04). Sulfate scales are hard and very difficult to remove, so treatment programs employed must be carefully controlled to avoid risks of scaling. 

Temperature-programmed reduction TPR was used to determine the reduction behaviors of the catalyst samples. It was carried out using 50 mg of a sample and a temperature ramp from 35 to 800°C at 5°C/min. The carrier gas was 5% H2 in Ar. A cold trap was placed before the detector to remove water produced during the reaction. 

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