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Final Shape (final + shape)
Selected AbstractsFlattGen: Teaching tool for surface flatteningCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2006Simon Kolmani Abstract In many cases in the industry, we can face a problem, where an object has to be manufactured out of thin plane material. This is especially the case in the car, airplane, shipbuilding, textile, and shoe making industry. In order to manufacture such an object, a pattern has to be generated first. It has to be cut out from plane material and then bend to the final shape. The same problem can be found also in computer graphics, where flat patterns are used to decrease distortions in texture mapping. Therefore, it is important for designers and computer engineers to master the flat pattern generation. In literature, a great number of methods for pattern generation can be found and it is important to know their advantages and weaknesses. In this article, the application FlattGen is presented where the most important flattening methods can be seen and compared to each other. In this way, students can experiment and prepare themselves better for the future work. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 106,119, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20060 [source] Shape-Controlled Synthesis of Pd Nanocrystals in Aqueous SolutionsADVANCED FUNCTIONAL MATERIALS, Issue 2 2009Byungkwon Lim Abstract This article provides an overview of recent developments regarding synthesis of Pd nanocrystals with well-controlled shapes in aqueous solutions. In a solution-phase synthesis, the final shape taken by a nanocrystal is determined by the twin structures of seeds and the growth rates of different crystallographic facets. Here, the maneuvering of these factors in an aqueous system to achieve shape control for Pd nanocrystals is discussed. L -ascorbic acid, citric acid, and poly(vinyl pyrrolidone) are tested for manipulating the reduction kinetics, with citric acid and Br, ions used as capping agents to selectively promote the formation of {111} and {100} facets, respectively. The distribution of single-crystal versus multiple-twinned seeds can be further manipulated by employing or blocking oxidative etching. The shapes obtained for the Pd nanocrystals include truncated octahedron, icosahedron, octahedron, decahedron, hexagonal and triangular plates, rectangular bar, and cube. The ability to control the shape of Pd nanocrystals provides a great opportunity to systematically investigate their catalytic, electrical, and plasmonic properties. [source] ProTaper rotary root canal preparation: effects of canal anatomy on final shape analysed by micro CTINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2003O. A. Peters No abstract is available for this article. [source] The standardized-taper root canal preparation , Part 6.INTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2001GT file technique in abruptly curved canals Abstract Aim, To describe the application of GT files in roots with abrupt curvatures. Summary Most dentists interpret obstructions to instrument progress as calcification, rather than abrupt curvature. Basically, there are not any apically calcified canals, only clinicians who are not clever enough or patient enough to sneak to patency. Dentists should be on their guard and sensitive to the ,rubber band' sensation of residual pulp tissue, and the ,loose resistance' sensation of the curved or ledged canal. Residual pulp tissue should be removed and the canal lubricated. The ledged or curved canal will only be helped by file bending. The size 10 file test is the key to identify canals requiring pre-bent instruments. The canal should first be flared short of the obstruction, before shaping the canal after it with regular, pre-bent K-files. Pre-bent GT hand-files can then be used with care to blend the apical and more coronal regions for final shape. Cone-fit may then require chilling and pre-bending GP cones (pre-bend more than one), before packing the canal. Key learning points ,Root canals do not calcify apically. ,File progress is prevented by pulp tissue, abrupt curvatures or ledging. ,Loose resistance to the passage of a size 10 file shows the canals that require instrument pre-bending. This test should be repeated at intervals during the preparation. ,Even NiTi GT files can be pre-bent for use in abrupt curves. ,Gutta percha cones can be pre-bent after chilling. [source] Molt and growth of an estuarine crab, Chasmagnathus granulatus (Brachyura: Varunidae), in Mar Chiquita coastal lagoon, ArgentinaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2004T. A. Luppi Summary Juvenile and adult growth of Chasmagnathus granulatus was studied in the laboratory in terms of molt increment in size (MI) and the intermolt period (IP), comparing data obtained from short-term (STE) and long-term (LTE) laboratory experiments. Crabs in a pre-molt condition were collected for STE, including the entire size range of the species. Larger crabs remained in the laboratory no more than 14 days; the average time to molt was 5.8 ± 3.1 days. We registered the molt of 94 females, 64 males and 34 undifferentiated juveniles and calculated their MI. Moreover, 24 males and four females were reared in the laboratory over 3 years (LTE). Hiatt diagrams did not show sex-specific differences between juveniles of both sexes, but revealed differences between juveniles and adults in each sex as well as between adults of both sexes. The MI decreased gradually with size; this pattern was described with a quadratic model. The IP increased exponentially with size. The presence of regenerating limbs diminished the MI. The abdomen of females reached its final shape and maximum relative width at functional maturity. Growth curves for both sexes were calculated using the von Bertalanffy model, but this model yielded an underestimation of the actual maximum size of this crab. [source] A new austenitic alumina forming alloy: an aluminium-coated FeNi32Cr20MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 6 2008H. Hattendorf Abstract The FeCrAl alloys owe their low oxidation rate to the formation of a slow growing , -aluminium oxide scale. Therefore they are used, for example, as a substrate material in metal-supported automotive catalytic converters. Increasing exhaust gas temperatures mean that, in addition to the oxidation properties, high temperature mechanical properties should also be improved. Compared to the ferritic FeCrAl alloys, austenitic alloys possess the required high mechanical strength at higher temperatures. However for most commercially available materials the oxidation resistance is not sufficient due to a low aluminium content. High aluminium contents are avoided in austenitic alloys, since they cause severe workability problems, even at aluminium contents, which are below the necessary amount to get a pure alumina scale. The newly developed material Nicrofer 3220 PAl (coated FeNiCrAl) consists of an austenitic FeNi32Cr20 alloy coated with aluminium on both sides. It combines the outstanding oxidation resistance of an alumina forming FeCrAl alloy with the advantage of the high temperature strength of an austenitic alloy. Additionally the oxidation is even lower than the oxidation of the commercial grade Aluchrom YHf (FeCr20Al6),conventional homogenous FeCrAl. Aluminium coated FeNiCrAl can easily be formed into its final shape. Prior to service, an in situ heat treatment is recommended in order to optimize the properties. [source] Self-organized growth of InN-nanocolumns on p-Si(111) by MBEPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008Christian Denker Abstract InN-nanocolumns are an attractive system for light harvesting applications. To understand the mechanism of self organized growth of nanocolumns in plasma assisted MBE, InN samples were produced under various conditions on p-Si(111). Depending on the growth parameters different growth regimes for nanocolumns were identified according to their final shape. High-resolution TEM pictures show a very good crystal quality. This is also confirmed by Raman and PL measurements. Nanocolumns with diameters of 20-200 nm and lengths of up to 2 mm were produced. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Compensating for die swell in the design of profile diesPOLYMER ENGINEERING & SCIENCE, Issue 10 2003W. A. Gifford Because of the effects of die swell, the final shape of an extrudate is often substantially different from that of the exit opening of the die. As a result, the design of profile dies producing complex shapes often involves more than just "balancing" the die but also compensating for the effects of die swell. Typically, a successful design of such dies is achieved only through much "cut and try," However, with the use of a fully three-dimensional finite element flow algorithm along with quick mesh generating capabilities, the usual cut and try involved in the design of many profile dies can be greatly reduced, if not eliminated. This paper demonstrates how the effects of die swell can be compensated for in the design of profile dies. For profiles with one plane of symmetry, this includes compensating for the sideways translation of the extrudate as well as the change in shape that the extrudate experiences. Completely asymmetric profiles undergo a "twisting" downstream of the die. This twisting, which appears not to have been reported in the literature (at least for isothermal extrusion), is also accounted for here, along with the change in shape that the extrudate undergoes. The translation or twisting of profiles downstream of a die is often attributed to non-Newtonian or non-isothermal effects. Only isothermal Newtonian examples are considered here. These results clearly show that asymmetry of the profile will result in a translation and twisting of the extrudate even in the isothermal Newtonian case. [source] | ||||||||||