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901.
The effect of weathering and thermal treatment on the scratch recovery characteristics of clearcoats
Christopher Seubert Mark Nichols Karen Henderson Markus Mechtel Thomas Klimmasch Torsten Pohl 《Journal of Coatings Technology and Research》2010,7(2):159-166
The scratch and scratch recovery characteristics of two clearcoats, a polyurethane and an acrylic/melamine/silane clearcoat,
were measured by a variety of methods. On most size scales tested, the polyurethane possessed superior scratch and mar resistance.
The polyurethane also possessed improved scratch recovery after warming for 2 h at 60°C. After 2000 h of accelerated weathering,
the scratch recovery characteristics of the polyurethane were largely maintained, while the acrylic/melamine/silane showed
a significant drop in scratch recovery performance. Performance of both coatings was related to T
g, hardness, and crosslink density. 相似文献
902.
R. Daniel Costley Mark E. Henderson Hitesh Patel E. William Jones Gary M. Boudreaux M. John Plodinec 《NDT & E International》2007,40(4):300-308
A non-intrusive technique has been developed which will detect an increase in pressure over ambient levels and alert workers of potential danger. Pressurization within the drum can be detected by measuring the frequency at which the drum lid vibrates; the natural frequencies increase as the pressure increases. It is shown that at high levels, the level of fill affects the frequency of the fundamental mode, but affects the higher modes to a much lesser degree. Thus, by measuring the frequencies of the fundamental and the first axisymmetric modes, the effect of fill level can be separated from pressurization. Analytical and experimental results are presented, along with suggestions for implementation. 相似文献
903.
Henderson Marlone D.; Fujita Kentaro; Trope Yaacov; Liberman Nira 《Canadian Metallurgical Quarterly》2006,91(5):845
Construal level theory proposes that increasing the reported spatial distance of events produces judgments that reflect abstract, schematic representations of the events. Across 4 experiments, the authors examined the impact of spatial distance on construal-dependent social judgments. Participants structured behavior into fewer, broader units (Study 1) and increasingly attributed behavior to enduring dispositions rather than situational constraints (Study 2) when the behavior was spatially distant rather than near. Participants reported that typical events were more likely and atypical events less likely when events were more spatially distant (Study 3). They were also less likely to extrapolate from specific cases that deviated from general trends when making predictions about more spatially distant events (Study 4). Implications for social judgment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
904.
905.
Sigrun N. Karlsdottir John W. Halloran Carl E. Henderson 《Journal of the American Ceramic Society》2007,90(9):2863-2867
During the high-temperature oxidation of ZrB2 –SiC composites, liquid boron oxide (B2 O3 ) is formed at the zirconium diboride–zirconium oxide interface and transported through the overlying layer of silica liquid by convection, forming distinct convection cells arranged like the petals of a flower. The convection cells are localized by a viscous fingering phenomenon, as the fluid B2 O3 rich liquid solution rises through the viscous silica layer. The upwelling B2 O3 rich liquid contains dissolved zirconium dioxide, which deposits in the center of the flower-like structure as the B2 O3 evaporates. The driving force for the B2 O3 liquid flow is the volume increase upon oxidation of ZrB2 . Convective transport of B2 O3 liquids suggests a novel mechanism for the high-temperature oxidation of these materials. 相似文献
906.
BT Messmer JJ Sullivan N Chiorazzi TC Rodman DS Thaler 《Canadian Metallurgical Quarterly》1999,162(4):2184-2192
Two monoclonal IgM Abs have been produced from lymphocytes isolated from two human umbilical cord bloods. These mAbs recognize a conformational epitope present in a CNBr digestion fraction of lactoferrin. Linear epitopes recognized by each mAb were selected from several phage display peptide libraries. In each case, phages displaying a peptide with a motif defined by [WF],G,[EQS],N were recovered. Phages displaying that motif bound equally well to either mAb but did not bind to control IgM. A peptide bearing this motif competed with the phage-displayed peptides for binding to either mAb. The same peptide also competes with a component of the CNBr digestion fraction of lactoferrin for Ab binding in ELISA. The Abs use different families of VH, JH, and VK gene cassettes but use the same JK cassette. All segments are virtually identical to their germline gene counterparts. This work provides further evidence that certain innate specificities are stereotyped among individuals. 相似文献
907.
908.
BR O'Keefe JA Beutler JH Cardellina TR Prather RH Shoemaker RC Sowder LE Henderson LK Pannell MR Boyd 《Canadian Metallurgical Quarterly》1997,60(11):1094-1099
Aqueous extracts from the New Zealand sponge Tethya ingalli (Hadromerida) displayed potent cytotoxicity in the NCI's 60-cell-line human tumor panel. Fractionation of the extract by ammonium sulfate precipitation, gel filtration, ultrafiltration, and both hydrophobic interaction and reversed-phase chromatography resulted in the isolation of two biologically active proteins. The first protein, Tethya protease inhibitor (TPI), which was purified to homogeneity, inhibited trypsin with an EC50 of 65 nM. TPI had a molecular mass of 11,431 Da, and an isoelectric point of 8.2. A partial N-terminal amino acid sequence determined for TPI showed significant homology with protease inhibitors of the Kunitz family. The second isolated protein displayed potent cytotoxicity, with pronounced selectivity for certain tumor cell lines (e.g., ovarian, renal, CNS, and breast). The latter protein, which had an apparent molecular weight of 21 kDa (SDS-PAGE), also lysed human red blood cells (EC50 of 39 nM) and was similar to a hemolysin previously isolated from the sponge Tethya lycinurium. 相似文献
909.
910.