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21.
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
22.
Sarala Arunagiri Yipkei Kwok Patricia J. Teller Ricardo A. Portillo Seetharami R. Seelam 《International journal of parallel programming》2014,42(1):165-197
Providing differentiated service in a consolidated storage environment is a challenging task. To address this problem, we introduce FAIRIO, a cycle-based I/O scheduling algorithm that provides differentiated service to workloads concurrently accessing a consolidated RAID storage system. FAIRIO enforces proportional sharing of I/O service through fair scheduling of disk time. During each cycle of the algorithm, I/O requests are scheduled according to workload weights and disk-time utilization history. Experiments, which were driven by the I/O request streams of real and synthetic I/O benchmarks and run on a modified version of DiskSim, provide evidence of FAIRIO’s effectiveness and demonstrate that fair scheduling of disk time is key to achieving differentiated service in a RAID storage system. In particular, the experimental results show that, for a broad range of workload request types, sizes, and access characteristics, the algorithm provides differentiated storage throughput that is within 10% of being perfectly proportional to workload weights; and, it achieves this with little or no degradation of aggregate throughput. The core design concepts of FAIRIO, including service-time allocation and history-driven compensation, potentially can be used to design I/O scheduling algorithms that provide workloads with differentiated service in storage systems comprised of RAIDs, multiple RAIDs, SANs, and hypervisors for Clouds. 相似文献
23.
24.
Fred N. Tebbe Patricia A. Morris Roger H. French Uma Chowdhry Robert L. Coble 《Journal of the American Ceramic Society》1988,71(4):204-C
Aluminum hydroxide obtained by hydrolysis of triethylaluminum is free of uranium and thorium at detection limits of 1 to 9 parts per billion (ppb). Other impurities commonly associated with aluminum oxides are present at low levels (Fe, ∼ 1 ppm; Si, 3 to 6 ppm). When the organoaluminum is intentionally contaminated with an iron salt, purity is restored by a simple distillation. 相似文献
25.
Patricia Quinlin Herman J. Weiser Jr. 《Journal of the American Oil Chemists' Society》1958,35(7):325-327
Summary Monoglyceride concentrates are quantitatively separated into mono-, di-, and triglyceride components on silica gel columns
by an adsorption chromatographic technique. The separated glycerides are determined gravimetrically. The adsorption on silica
gel is dependent on the number of hydroxyl groups in the molecule, and the influence of unsaturation and chain length is minimized.
Combinations of benzene and ethyl ether are used for elution, thus preventing isomerization, which frequently results when
polar solvents such as alcohols are used.
The procedure for the chromatographic separation is simple and straightforward. The equipment used is easily obtainable. The
silica gel adsorbent requires only adjustment of its water content before use.
Mixtures of both saturated and unsaturated glycerides and those having different fatty acid chain length have been separated.
Known mixtures have also been analyzed. For a known mixture containing 15% tripalmitin, 45% distearin, and 38% monopalmitin
the average deviations from the calculated values were 0.4%, 0.2%, and 0.6%, respectively 相似文献
26.
Dynamic memory allocation has been used for decades. However, it has seldom been used in real-time systems since the worst
case of spatial and temporal requirements for allocation and deallocation operations is either unbounded or bounded but with
a very large bound.
In this paper, a new allocator called TLSF (Two Level Segregated Fit) is presented. TLSF is designed and implemented to accommodate
real-time constraints. The proposed allocator exhibits time-bounded behaviour, O(1), and maintains a very good execution time. This paper describes in detail the data structures and functions provided by
TLSF. We also compare TLSF with a representative set of allocators regarding their temporal cost and fragmentation.
Although the paper is mainly focused on timing analysis, a brief study and comparative analysis of fragmentation incurred
by the allocators has been also included in order to provide a global view of the behaviour of the allocators.
The temporal and spatial results showed that TLSF is also a fast allocator and produces a fragmentation close to that caused
by the best existing allocators.
相似文献
Alfons Crespo (Corresponding author)Email: |
27.
This paper is concerned with the derivation of infinite schedules for timed automata that are in some sense optimal. To cover
a wide class of optimality criteria we start out by introducing an extension of the (priced) timed automata model that includes
both costs and rewards as separate modelling features. A precise definition is then given of what constitutes optimal infinite
behaviours for this class of models. We subsequently show that the derivation of optimal non-terminating schedules for such
double-priced timed automata is computable. This is done by a reduction of the problem to the determination of optimal mean-cycles
in finite graphs with weighted edges. This reduction is obtained by introducing the so-called corner-point abstraction, a
powerful abstraction technique of which we show that it preserves optimal schedules.
This work has been mostly done while visiting CISS at Aalborg University in Denmark and has been supported by CISS and by
ACI Cortos, a program of the French Ministry of Research. 相似文献
28.
Mery Patricia Tamayo 《Industry and innovation》2017,24(2):143-164
This paper analyses the determinants of R&D offshoring of Spanish firms using information from the Panel of Technological Innovation. We find that being an exporter, international technological cooperation, continuous R&D engagement, applying for patents, being a foreign subsidiary, and firm size are factors that positively affect the decision to offshore R&D. In addition, we find that a lack of financing is an obstacle relatively more important for independent firms than for firms that belong to business groups. For these latter, we also obtain that the factors that influence the decision to offshore R&D differ depending on whether the firm purchases the R&D services within the group or through the market: a higher degree of importance assigned to internal sources of information for innovation as compared to market sources increases (decreases) the probability of R&D offshoring only through the group (market). 相似文献
29.
Patricia Bondia Rocío Jurado Santiago Casado José M. Domínguez‐Vera Natividad Gálvez Cristina Flors 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(17)
The combination of complementary techniques to characterize materials at the nanoscale is crucial to gain a more complete picture of their structure, a key step to design and fabricate new materials with improved properties and diverse functions. Here it is shown that correlative atomic force microscopy (AFM) and localization‐based super‐resolution microscopy is a useful tool that provides insight into the structure and emissive properties of fluorescent β‐lactoglobulin (βLG) amyloid‐like fibrils. These hybrid materials are made by functionalization of βLG with organic fluorophores and quantum dots, the latter being relevant for the production of 1D inorganic nanostructures templated by self‐assembling peptides. Simultaneous functionalization of βLG fibers by QD655 and QD525 allows for correlative AFM and two‐color super‐resolution fluorescence imaging of these hybrid materials. These experiments allow the combination of information about the topography and number of filaments that compose a fibril, as well as the emissive properties and nanoscale spatial distribution of the attached fluorophores. This study represents an important step forward in the characterization of multifunctionalized hybrid materials, a key challenge in nanoscience. 相似文献
30.