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Shape similarity tool

In the manufacture of percussion caps and detonators the copper blanks are cut from copper strips and stamped to the required shape. The blanks are then plaeed in a gun-metal plate, with the concave side uppermost—a tool composed of a plate of gim-metal, in which are inserted a number of copper points, each of the same length, and so spaced apart as to exactly fit each point into a cap when inverted over a plate containing the blanks. The points are dipped into a vessel containing the cap composition, which has been previously moistened with methylated spirit. It is then removed and placed over the blanks, and a slight blow serves to deposit a small portion of the eap mixture into each cap. A similar tool is then dipped into shellac... [Pg.74]

As also argued elsewhere [45], virtual screening is currently underused. This is particularly surprising in the case of academic laboratories, as most shape similarity is free of charge for academic purposes, in some cases the required computer resources are modest, and experimental validation requires sufficient resources to test as little as tens of virtual screening hits. More applications of shape matching tools are expected in the next few years, owing to the wide accessibility of freely available shape similarity software. ... [Pg.164]

There are a number of ways to repair windshield dings, including taking the car to a tepair shop, where it should take a technician five minutes to fill the nick, and your insurance company is likely to cover the repair pre-deductible (it would rather pay a little for a repair now than a lot for a replacement later). If you decide to do it yourself, buy a windshield repair kit at a car-parts store or online. Kit specifics will differ, but it should include a doughnut-shaped adhesive to surround the ding, a syringe or similar tool to pull air bubbles from the crack, and resin to fill it. [Pg.374]

Fig. 9 shows comparisons of CFD results with experimental data at a Reynolds number of 986 at three of the different bed depths at which experiments were conducted. The profiles are plotted as dimensionless temperature versus dimensionless radial position. The open symbols represent points from CFD simulation the closed symbols represent the points obtained from experiment. It can be seen that the CFD simulation reproduces the magnitude and trend of the experimental data very well. There is some under-prediction in the center of the bed however, the shapes of the profiles and the temperature drops in the vicinity of the wall are very similar to the experimental case. More extensive comparisons at different Reynolds numbers may be found in the original reference. This comparison gives confidence in interstitial CFD as a tool for studying heat transfer in packed tubes. [Pg.345]

Ribozymes are a class of metallo-enzymes based on RNA rather than proteins. They have potential in clinical medicine, for example, as potential anti-HIV agents (568, 569) and as possible new tools for the treatment of cancer (570). The active structures of ribozymes contain domains of stacked helices which pack together through tertiary contacts. Divalent metal ions such as Mg(II), Zn(II), and Mn(II) can tune the reactivity and shape the structures of ribozymes (571). Manganese(II) and Mg(II) have similar hexacoordinate ionic radii (0.86 and 0.97 A, respectively) (572) and octahedral geometry ( )Ka of hydrates Ca(II), 12.7 Mg(II), 11.4 Mn(II), 10.7 Zn2+, 9.6) (571). There are several potential oxygen donors on the ribose sugar moiety. [Pg.276]

Tbis explanation of enzyme action is belpful, but far from complete. For one thing, enzymes differ significantly in the ways that they interact with other compounds. Some enzymes bond and react with only specific compounds, while others bond and react with an array of compounds in a chemical family that have the same or similar functional groups. Some enzymes fit neatly into an opening in a substrate, while others actually change the shape of the substrate on which they operate. The fact that enzyme actions are so diverse simply conhrms that the chemical structures of enzymes and substrates differ signihcantly, and the chemical mechanisms by which they interact can be very complex indeed. In fact, the tools needed to understand the precise molecular shapes of enzymes and substrates have become available only recently. Once these shapes have become known, scientists are able to unravel the exact steps that take place when enzyme and substrate interact with each other. [Pg.120]

Rigid caul plates are typically constructed of thick metal or composite materials. Thick caul plates are used on very complex part applications or cocured parts where dimensional control is critical. Many rigid caul plates result in a matched die configuration similar to compression or resin transfer molding. Parts processed in this manner are extremely challenging because resin pressure is much more dependant on tool accuracy and the difference in thermal expansion between the tool and the part. Tool accuracy is critical to ensure no pinch points are encountered that would inhibit a tool from forming to the net shape of the part. [Pg.305]

Transient IR spectroscopy in the range of the amide I band is a direct tool to follow the structural dynamics of the peptide moiety. IR difference spectra on the bicyclic molecule bc-AMPB are plotted in Fig. 5. Shortly after excitation the absorption is dominated by a red shift. Such a red shift is expected for a strong vibrational excitation of the molecule. On the time-scale of a few picosecond this red shift decays to a large extent and is replaced by a dispersive feature of opposite sign at tD = 20 ps. At later delay times this feature changes details of its shape, it sharpens up and some substructure appears around 1680 cm 1. After 1.7 ns the shape is similar, but not completely identical to the difference spectrum recorded with stationary FTIR spectroscopy. This time dependence shows that the dominant structural change responsible for the IR difference spectrum occurs on the 20 ps time-scale and that minor structural changes continue until nanoseconds and even later times. [Pg.377]


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