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排序方式: 共有252条查询结果,搜索用时 46 毫秒
1.
2.
Patricia M. Cooney J. E. Hodge C. D. Evans 《Journal of the American Oil Chemists' Society》1958,35(4):167-171
Summary Amino reductones derived from hexoses were evaluated for color development in heated, oxidizing fat systems. Browning was
observed to some extent with all the amino-hexose-reductones. The brown color frequently faded upon long heating of the oils.
The density of color increased with reductone concentration and varied markedly among the different amino reductones. Morpholino-hexose-reductone
could be used in lard and vegetable oils at concentrations up to 0.01% without introducing visually detectable amounts of
color. Heating soybean oil solutions of the amino reductones at 100°C. under vacuum slowly destroyed the reductone but did
not cause development of color. Air or oxygen was required for color production. Addition of citric acid along with the reductone
reduced the amount of color developed. Reductones in fat systems show similarities in browning to reductones in aqueous systems.
New considerations for the mechanism of antioxidation by polyphenols and reductones in oils are presented.
Presented at the spring meeting, American Oil Chemists’ Society. New Orleans, La., April 28-May 1, 1957. 相似文献
3.
Victoria J. Hodge Rajesh Krishnan Jim Austin John Polak Tom Jackson 《Neural computing & applications》2014,25(7-8):1639-1655
This paper introduces a binary neural network-based prediction algorithm incorporating both spatial and temporal characteristics into the prediction process. The algorithm is used to predict short-term traffic flow by combining information from multiple traffic sensors (spatial lag) and time series prediction (temporal lag). It extends previously developed Advanced Uncertain Reasoning Architecture (AURA) k-nearest neighbour (k-NN) techniques. Our task was to produce a fast and accurate traffic flow predictor. The AURA k-NN predictor is comparable to other machine learning techniques with respect to recall accuracy but is able to train and predict rapidly. We incorporated consistency evaluations to determine whether the AURA k-NN has an ideal algorithmic configuration or an ideal data configuration or whether the settings needed to be varied for each data set. The results agree with previous research in that settings must be bespoke for each data set. This configuration process requires rapid and scalable learning to allow the predictor to be set-up for new data. The fast processing abilities of the AURA k-NN ensure this combinatorial optimisation will be computationally feasible for real-world applications. We intend to use the predictor to proactively manage traffic by predicting traffic volumes to anticipate traffic network problems. 相似文献
4.
The surface microstructure and polymorphic behavior of milk chocolate subjected to multiple thermal cycles between 20 and
32, 33, or 34°C were examined using atomic force microscopy (AFM) and powder X-ray diffraction (XRD). The surface of unbloomed
milk chocolate was smooth (surface roughness of 278 nm) and consisted of small, evenly distributed crystals. XRD results indicated
the presence of mostly form V crystals and little or no form VI crystals. Cycling between 20 and 32°C resulted in little bloom
formation and change in polymorphic behavior. Gradual bloom formation occurred as a result of cycling between 20 and 33°C,
and was accompanied by the nascence of form VI crystals. Surface roughness increased gradually from 417 nm after one cycle
to 476 and 521 nm after two and three cycles, respectively. Extensive bloom arose from cycling between 20 and 34°C. Surface
roughness increased from 373 nm after one cycle to 603 and 736 nm after two and three cycles, respectively. This heavily bloomed
chocolate consisted of jutting crystals and large raised, yet smooth areas that were haphazardly located within the chocolate
matrix. In summary, a new perspective on the development of surface bloom due to thermal cycling is provided. 相似文献
5.
Gerald Hodge 《Journal of the American Planning Association. American Planning Association》2013,79(2):112-121
By developing measurement scales the city planner can promote his long-run interest in integrating urban knowledge and his short-run interest in making valid analyses of specific problems. But the construction of measurement scales is not a random process and must be conducted according to logical rules. Inadequacies in current city planning scales are largely attributable to the lack of adherence to these rules. Housing quality scales, the most common measurement device in city planning, reveal some of the difficulties that lead to deficiencies in our measurement. The outlook is far from gloomy. Experience from other fields in index number construction, the use of scalograms, and factor analysis can Open up many promising avenues for city planning measurement. 相似文献
6.
Platinum and palladium in roadside dust 总被引:4,自引:0,他引:4
7.
Mechanical Properties of an Fe‐Based SAM2×5‐630 Metallic Glass Matrix Composite with Tungsten Particle Additions 下载免费PDF全文
I‐Chung Cheng James P. Kelly Ekaterina Novitskaya Veronica Eliasson Andrea M. Hodge Olivia A. Graeve 《Advanced Engineering Materials》2018,20(9)
We present the role of tungsten additions on the mechanical properties of a Fe‐based structural amorphous metal (SAM2×5‐630) containing crystalline tungsten. Matrix cracking by microindentation is inhibited by the addition of tungsten and indicates that tungsten improves the fracture toughness. Response surfaces from nanoindentation arrays indicate that the hardness and modulus of the matrix phase are increased by tungsten additions. Bulk composites with 30 vol% tungsten subjected to 4‐point flexure exhibited brittle fracture behavior and the characteristic strength and Weibull modulus were 165 and 8.7 MPa, respectively. The addition of tungsten did not cause devitrification of the matrix phase. 相似文献
8.
JJ Milavetz TD Miller DO Hodge DR Holmes RJ Gibbons 《Canadian Metallurgical Quarterly》1998,82(7):857-861
Strategies to noninvasively evaluate patients after coronary stenting have not been evaluated. To determine the accuracy of single-photon emission computed tomography (SPECT) myocardial perfusion imaging in patients after coronary stenting, 209 patients who had undergone stenting followed by late stress SPECT myocardial perfusion imaging were evaluated. Quantitative coronary angiography was performed in 33 patients following SPECT imaging. SPECT restenosis was defined as a reversible or fixed defect within the stented vascular territory. Angiographic restenosis was examined using 2 definitions: total area narrowing > or =50% or > or =70% of the stent site or stented artery. The SPECT and angiographic findings were concordant in 22 of 33 stented vascular territories using the 50% definition of restenosis and in 29 of 33 stented territories using the 70% definition. Use of the 70% definition of restenosis resulted in improved accuracy of SPECT to detect a significant stenosis in the stented artery. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SPECT were 95%, 73%, 88%, 89%, and 88% respectively. In patients with positive SPECT scans, the most significant stenosis in the stented artery was outside the stent site in 50% of cases. SPECT imaging appears to be accurate to predict significant stenosis in the stented artery, although the most severe stenosis is frequently distant from the stent site. 相似文献
9.
Spin angular momentum conservation in chemiionization reactions involving optically oriented He(2(3)S) atoms in a flowing helium afterglow has been exploited to yield a source of spin-polarized electrons. Either transversely or longitudinally polarized electrons can be extracted. Polarized electron beam currents of approximately 2 muA have been realized at 40% polarization. The beam has an effective emittance of approximately 2 mrad/cm over the energy range 100-400 eV, an energy spread of less, similar0.15 eV, and the polarization is readily reversible. The source is relatively inexpensive and appears suitable for the majority of low-energy spin-dependent scattering experiments proposed to date. 相似文献
10.
The existence of a psoriasis susceptibility locus, PSORS1 (HUGO/GDB-approved symbol), in or near the HLA region of chromosome 6 is strongly supported by a lod score analysis of HLA-B and psoriasis in 97 families from 16 published datasets. Families included in the dataset represent all the psoriasis families with usable HLA data that we could find in the published literature through May 1997. The recombination fraction between PSORS1 and HLA-B is estimated to be at or near 0.00, with a maximum two-point lod score of 23.7, assuming a dominant mode of inheritance with low (20%) penetrance at the PSORS1 locus. Although these families are geographically and ethnically diverse, there is no evidence for linkage heterogeneity at the HLA-linked locus in this analysis. We also conclude that the HLA-B17 allele, which is strongly associated with psoriasis, is unlikely itself to contribute directly to psoriasis susceptibility; rather, the HLA-B locus is probably tightly linked to the PSORS1 locus. Finally, we raise the possibility of a two-locus/heterogeneity model as one way to reconcile several findings in the literature. 相似文献