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Menhaden and cod liver oils without additives or containing either α-tocopherol (670 ppm) or Trolox C (1000 ppm) with or without
copper (II) cations (20 ppm) were oxidized under air at 65‡C, and their headspace volatiles were quantitatively measured by
capillary gas chromatography. Samples prepared without additives contained very little l,5-octadien-3-one. Fish oils with
Trolox C had distinct metallic, vinyl-ketone aromas, while those with a-tocopherol exhibited extremely fishy, cod liver-like
aromas. High levels of 1,5-octadien-3-one and 1,5-octadien-3-ol and moderate levels of 2,4,7-decatrienals were found in samples
with Trolox C, while moderate levels of the 8-carbon compounds and high levels of the 2,4,7-decatrienals were present in the
α-tocopherol samples. Copper (II) greatly accelerated the overall rate of oxidation in samples, and in the presence of Trolox
C it induced the formation of very high levels of 1,5-octadien-3-ol. 相似文献
64.
Universal reaction-limited colloid aggregation 总被引:1,自引:0,他引:1
MY Lin HM Lindsay DA Weitz RC Ball R Klein P Meakin 《Canadian Metallurgical Quarterly》1990,41(4):2005-2020
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Definitions of business process given in much of the literature on Business Process Management are limited in depth and their related models of business processes are correspondingly constrained. After giving a brief history of the progress of business process modeling techniques from production systems to the office environment, this paper proposes that most definitions are based on machine metaphor type explorations of a process. While these techniques are often rich and illuminating it is suggested that they are too limited to express the true nature of business processes that need to develop and adapt to today's challenging environment. 相似文献
68.
Quas Jodi A.; Malloy Lindsay C.; Melinder Annika; Goodman Gail S.; D'Mello Michelle; Schaaf Jennifer 《Canadian Metallurgical Quarterly》2007,43(4):823
The present study investigated developmental differences in the effects of repeated interviews and interviewer bias on children's memory and suggestibility. Three- and 5-year-olds were singly or repeatedly interviewed about a play event by a highly biased or control interviewer. Children interviewed once by the biased interviewer after a long delay made the most errors. Children interviewed repeatedly, regardless of interviewer bias, were more accurate and less likely to falsely claim that they played with a man. In free recall, among children questioned once after a long delay by the biased interviewer, 5-year-olds were more likely than were 3-year-olds to claim falsely that they played with a man. However, in response to direct questions, 3-year-olds were more easily manipulated into implying that they played with him. Findings suggest that interviewer bias is particularly problematic when children's memory has weakened. In contrast, repeated interviews that occur a short time after a to-be-remembered event do not necessarily increase children's errors, even when interviews include misleading questions and interviewer bias. Implications for developmental differences in memory and suggestibility are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Hatch LE Creamean JM Ault AP Surratt JD Chan MN Seinfeld JH Edgerton ES Su Y Prather KA 《Environmental science & technology》2011,45(12):5105-5111
Organosulfate species have recently been identified as a potentially significant class of secondary organic aerosol (SOA) species, yet little is known about their behavior in the atmosphere. In this work, organosulfates were observed in individual ambient aerosols using single particle mass spectrometry in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Organosulfates derived from biogenically produced isoprene were detected as deprotonated molecular ions in negative-ion spectra measured by aerosol time-of-flight mass spectrometry; comparison to high-resolution mass spectrometry data obtained from filter samples corroborated the peak assignments. The size-resolved chemical composition measurements revealed that organosulfate species were mostly detected in submicrometer aerosols and across a range of aerosols from different sources, consistent with secondary reaction products. Detection of organosulfates in a large fraction of negative-ion ambient spectra - ca. 90-95% during ANARChE and ~65% of submicrometer particles in AMIGAS - highlights the ubiquity of organosulfate species in the ambient aerosols of biogenically influenced urban environments. 相似文献
70.
Due to their sensitivity and temporal response, optical microresonators are used extensively in the biosensor arena, particularly in the development of label-free diagnostics and measurement of protein kinetics. In the present letter, we investigate using microcavities to probe molecules within biomimetic membranes. Specifically, a method for self-assembling lipid bilayers on spherical microresonators is developed and the bilayer-nature is verified. Subsequently, the microcavity is used to excite a Cy5-conjugated lipid located within the bilayer while the optical performance of the microcavity is characterized. The emission wavelength of the dye and the optical behavior of the microcavity agree with theoretical predictions. 相似文献