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71.
The metabolism of α-linolenic acid from canola oil was studied in eight normolipidemic men. The 42-day study was divided into
three periods: a 6-day pre-experimental and two 18-day experimental. Approximately 75% of the dietary fat (28% of total energy)
was provided by a mixture of fats during the pre-experimental period and either canola oil (CO) or sunflower oil (SO) during
the experimental periods. The CO and SO diets were fed in a cross-over design. The ratios of linoleic to linolenic acid were
2.6∶1 and 73.9∶1 in the CO and SO diets, respectively. Dietary fat source had an effect on plasma phospholipid fatty acids:
18∶1n−9, 18∶3n−3 and 20∶5n−3 were higher (p<0.05), and 18∶2n−6 was lower in the phosphatidylcholine fraction; 18∶1n−9 was
higher and 20∶4n−6 lower in the phosphatidyl-ethanolamine fraction; and 18∶1n−9 and 20∶5n−3 were higher and 20∶4n−6 and 22∶6n−3
were lower in the alkenylacyl-ethanolamine phospholipid fraction on the CO diet as compared to the SO diet. Consumption of
the canola oil diet resulted in higher n−3 fatty acid levels and lower n−6 fatty acid levels in plasma phospholipids than
consumption of the sunflower oil diet. 相似文献
72.
Garrett BC Dixon DA Camaioni DM Chipman DM Johnson MA Jonah CD Kimmel GA Miller JH Rescigno TN Rossky PJ Xantheas SS Colson SD Laufer AH Ray D Barbara PF Bartels DM Becker KH Bowen KH Bradforth SE Carmichael I Coe JV Corrales LR Cowin JP Dupuis M Eisenthal KB Franz JA Gutowski MS Jordan KD Kay BD Laverne JA Lymar SV Madey TE McCurdy CW Meisel D Mukamel S Nilsson AR Orlando TM Petrik NG Pimblott SM Rustad JR Schenter GK Singer SJ Tokmakoff A Wang LS Wettig C Zwier TS 《Chemical reviews》2005,105(1):355-390
73.
74.
Bong-Kyu Chang Yong Lu Hongyun Yang Bruce J. Tatarchuk 《Journal of Materials Engineering and Performance》2006,15(4):439-441
In this study, a microfibrous carrier consisting of 3 vol.% of 8 μm (diameter) glass fibers is used to entrap 45 vol.% of
150 to 250 μm (diameter) SiO2 support particulates. ZnO is then nanodispersed onto the support by impregnation at the loading of 17 wt.%. At equivalent
bed volumes, ZnO/SiO2-entrapped materials provide twofold longer breakthrough times for H2S (with a 67% reduction in sorbent loading) compared with packed beds of 1 to 2 mm commercial extrudates. Five-log reductions
in H2S concentration with up to 75% ZnO utilization at breakthrough are achieved. H2S concentrations from 60 to 2000 parts per million in volume (ppmv) can be reduced to as little as 0.6 ppmv at 400°C in 30%
H2O at a face velocity of 1.7 cm/s for layers as thin as 1.0 mm. At 500 to 600°C, ZnO/SiO2-entrapped materials provide much higher regenerability in air than do 1 to 2 mm commercial extrudates. The use of glass fibers
permits greater than 50 regeneration cycles.
This paper was presented at the ASM Materials Solutions Conference & Show held October 18–21, 2004 in Columbus, OH. 相似文献
75.
Kevin P. Nolan Akshat Agarwal Shenghui Lei Robin Shields 《Microfluidics and nanofluidics》2016,20(7):101
Detailed measurements of the flow instability of dilute shear-thinning viscoelastic aqueous solutions, with relatively low zero-shear viscosities, in an obstructed microchannel flow are reported. We examine the flow behaviour resulting from a 100 μm post placed in the channel centreline over a range of Reynolds numbers (\(5<Re<300\)) and Weissenberg numbers (\(20<Wi<10^3\)). Micro-particle image velocimetry measurements show the onset of an upstream instability within a Reynolds number range and at a critical elasticity number corresponding to polymer concentrations above 25 ppm of long-chain polyacrylamide. The instability results in significant local fluctuations in the flow field approaching 30 % of the mean velocity. The magnitude of the local viscosity ratio in the region upstream of the post is proposed as a driving mechanism for the instability which resembles a buckling flow. Additionally, the classical instability owing to separation and vortex formation downstream of the post in Newtonian flow is suppressed and a very long stable wake is observed extending over 10 post-diameters downstream. 相似文献
76.
We present the design, fabrication, and performance of the multi-specimen heated platform for linear in situ heating during the Temperature-Programmed XPS (TPXPS). The platform is versatile, compatible with high vacuum (HV) and bakeout. The heater platform is tested under in situ linear heating of typical high surface area sorbent∕catalyst support--nanoporous TiO(2). The platform allows the TPXPS of multiple samples located on specimen disk that can be transferred in and out of the TPXPS chamber. Electric characteristics, temperature and pressure curves are provided. Heating power supply, PID temperature controller, data-logging hardware and software are described. 相似文献
77.
Stuart Nolan 《Digital Creativity》2013,24(3):185-192
Abstract This paper reports on 12 participatory design workshops involving 216 young people, aged 9 to 16. It discusses responses to existing and proposed locative and pervasive media technologies in gaming, mapping, gifting, game design, bodystorming, and collaborative storytelling activities. Issues of the technomagical in scenario planning are discussed. 相似文献
78.
Abstract Research in mathematics and science education frequently directs one's attention to the limited content knowledge of elementary pre‐service teachers. It is believed, however, that research of this nature leads to a deficit approach to understanding more about the teaching and learning of these subjects. In addition to focusing on the knowers of school mathematics and science, there is a call to acknowledge the problematic nature of knowing (in) mathematics and science. In this paper, the metaphor of shadows is used in a critical exploration of what it means to know and how the cultures of classrooms have shaped these images of knowing. Through the voices of pre‐service teachers, this paper directs one's attention to objects that cast shadows on the learning and knowing of mathematics and science. Three such shadow‐casting objects discussed in this paper are textbooks, teachers, and gendered ideology. The paper seeks to critically illuminate the problematic nature of what it means to know (in) mathematics and science by examining the shadowy texture of unquestioned ideologies. 相似文献
79.
We introduce the notion of ranking robustness, which refers to a property of a ranked list of documents that indicates how
stable the ranking is in the presence of uncertainty in the ranked documents. We propose a statistical measure called the
robustness score to quantify this notion. Our initial motivation for measuring ranking robustness is to predict topic difficulty
for content-based queries in the ad-hoc retrieval task. Our results demonstrate that the robustness score is positively and
consistently correlation with average precision of content-based queries across a variety of TREC test collections. Though
our focus is on prediction under the ad-hoc retrieval task, we observe an interesting negative correlation with query performance
when our technique is applied to named-page finding queries, which are a fundamentally different kind of queries. A side effect
of this different behavior of the robustness score between the two types of queries is that the robustness score is also found
to be a good feature for query classification.
相似文献
80.
Jungkyu Kim Michael Junkin Deok-Ho Kim Seunglee Kwon Young Shik Shin Pak Kin Wong Bruce K. Gale 《Microfluidics and nanofluidics》2009,7(2):149-167
Biosensors based on nanotechnology are rapidly developing and are becoming widespread in the biomedical field and analytical
chemistry. For these nanobiosensors to reach their potential, they must be integrated with appropriate packaging techniques,
which are usually based on nano/microfluidics. In this review we provide a summary of the latest developments in nanobiosensors
with a focus on label-based (fluorescence and nanoparticle) and label-free methods (surface plasmon resonance, micro/nanocantilever,
nanowires, and nanopores). An overview on how these sensors interface with nano/microfluidics is then presented and the latest
papers in the area summarized. 相似文献