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41.
Effects of conjugated linoleic acid isomers on the hepatic microsomal desaturation activities in vitro 总被引:4,自引:0,他引:4
The influence of individual conjugated linoleic acid (CLA) isomers on the Δ6 desaturation of linoleic and α-linolenic acids
and on the Δ9 desaturation of stearic acid was investigated in vitro, using rat liver microsomes. The Δ6 desaturation of 18∶2n−6 was decreased from 23 to 38% when the ratio of 9cis,11trans-18∶2 to 18∶2n−6 increased from 0.5 to 2. The compound 10trans,12cis-18∶2 exhibited a similar effect only at the highest concentration. The Δ6 desaturation of α-linolenic acid was slightly affected
by the presence of CLA isomers. The sole isomer to induce an inhibitory effect on the Δ9 desaturation of stearic acid was
10trans,12cis-18∶2. 相似文献
42.
Rajmund S. Dybczyński Marta Pyszynska Krzysztof Kulisa Anna Bojanowska-Czajka 《分离科学与技术》2020,55(7):1364-1379
ABSTRACTNew ion interaction chromatographic (IIC) method employing Kromasil 100 C18 column and tetra-n-butylammonium hydroxide (TBAOH) as an ion interaction reagent (IIR) is able to separate yttrium from Rare Earth Elements (REE) as anionic complexes with nitrilotriacetic acid (NTA). New method for the chromatographic determination of Y in REE mixture was devised and validated by the analysis of the certified reference material (CRM). Potential possibilities of the new chromatographic system for larger scale applications including macro-micro events were demonstrated. 相似文献
43.
Ciesielczyk Tomasz Cabrera Alberto Oleksiak Ariel Piątek Wojciech Waligóra Grzegorz Almeida Francisco Blanco Vicente 《Journal of Scheduling》2021,24(5):489-505
Journal of Scheduling - Rapid growth of demand for remote computational power, along with high energy costs and infrastructure limits, has led to treating power usage as a primary constraint in... 相似文献
44.
Z. Moser W. Gąsior K. Bukat J. Pstruś R. Kisiel J. Sitek K. Ishida I. Ohnuma 《Journal of Phase Equilibria and Diffusion》2006,27(2):133-139
Maximum bubble pressure, dilatometric, and meniscographic methods were used in the investigations of the surface tension,
density, wetting time, wetting force, contact angle, and interfacial tension of liquid alloys of Sn−Ag−Cu eutectic composition
with various additions of Bi. Density and surface tension measurements were conducted in the temperature range 250–900 °C.
Surface tensions at 250 °C measured under a protective atmosphere of Ar−H2 were combined with data from meniscographic studies done under air or with a protective flux. The meniscographic data with
a nonwetted teflon substrate provided data on interfacial tension (solder-flux), surface tension in air, and meniscographic
data with a Cu substrate allowed determinations of wetting time, wetting force, and calculation of contact angle. The calculated
wetting angles from meniscographic studies for binary Sn−Ag eutectic and two ternary Sn−Ag−Cu alloys were verified by separate
measurements by the sessile drop method under a protective atmosphere with a Cu substrate. Additions of Bi to both ternary
alloys improve the wettability and move the parameters somewhat closer to those of traditional Sn−Pb solders. 相似文献
45.
I. Ohnuma K. Ishida Z. Moser S. Gąsior K. Bukat J. Pstruś R. Kisiel J. Sitek 《Journal of Phase Equilibria and Diffusion》2006,27(3):245-254
The ADAMIS database was used for calculation of the surface tension of the quaternary Sn−Ag−Cu−Bi liquid alloys by Butler's
model. The resultant data were compared with those from the maximum bubble pressure measurements from Part I. The same thermodynamic
database was next applied for the calculation of various phase equilibria. It was established that the Bi addition to the
ternary Sn−Ag−Cu alloys (Sn-2.6Ag-0.46Cu and Sn-3.13Ag-0.74Cu in at.%; Sn-2.56Ag-0.26 Cu and Sn-2.86Ag-O.40Cu in mass%) causes
lowering of the melting temperature and the surface tension to make the tested alloys closer to, traditional Sn−Pb solders.
The simulation of the solidification by Scheil's model showed that the alloys with the higher Bi concentration are characterized
by the lifting-off failure due to the segregation of Bi at the solder/substrate boundary. Thus, in modeling of new Pb-free
solders, a compromise among various properties should be taken into consideration. 相似文献
46.
In this paper, basic relationships and algorithms for numerical simulation of non-linear, self-excited vibrations in single degree-of-freedom cutting systems are presented. Non-linearities due to the tool leaving the cut, as well as interference between the cutting tool clearance face and cutting surface waviness, were taken into consideration. Examples of vibration simulation results are shown. 相似文献
47.
Robustness of ISS systems to inputs with limited moving average: Application to spacecraft formations
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Esten Ingar Grøtli Elena Panteley Antoine Chaillet Jan Tommy Gravdahl 《国际强度与非线性控制杂志
》2016,26(4):816-833
》2016,26(4):816-833
We provide a theoretical framework that fits realistic challenges related to spacecraft formation with disturbances. We show that the input‐to‐state stability of such systems guarantees some robustness with respect to a class of signals with bounded average‐energy, which encompasses the typical disturbances acting on spacecraft formations. Solutions are shown to converge to the desired formation, up to an offset, which is somewhat proportional to the considered moving average of disturbances. In the presence of fast peaking perturbations, the approach provides a tighter evaluation of the disturbances' influence, which allows for the use of more parsimonious control gains. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
48.
Krzysztof Michalak 《Optimization methods & software》2016,31(2):392-404
Evolutionary algorithms (EAs) are often employed to multiobjective optimization, because they process an entire population of solutions which can be used as an approximation of the Pareto front of the tackled problem. It is a common practice to couple local search with evolutionary algorithms, especially in the context of combinatorial optimization. In this paper a new local search method is proposed that utilizes the knowledge concerning promising search directions. The proposed method can be used as a general framework and combined with many methods of iterating over a neighbourhood of an initial solution as well as various decomposition approaches. In the experiments the proposed local search method was used with an EA and tested on 2-, 3- and 4-objective versions of two well-known combinatorial optimization problems: the travelling salesman problem (TSP) and the quadratic assignment problem (QAP). For comparison two well-known local search methods, one based on Pareto dominance and the other based on decomposition, were used with the same EA. The results show that the EA coupled with the directional local search yields better results than the same EA coupled with any of the two reference methods on both the TSP and QAP problems. 相似文献
49.
Mobile context-based framework for threat monitoring in urban environment with social threat monitor
Szymon Bobek Grzegorz J. Nalepa Antoni Ligȩza Weronika T. Adrian Krzysztof Kaczor 《Multimedia Tools and Applications》2016,75(17):10595-10616
Engaging users in threat reporting is important in order to improve threat monitoring in urban environments. Today, mobile applications are mostly used to provide basic reporting interfaces. With a rapid evolution of mobile devices, the idea of context awareness has gained a remarkable popularity in recent years. Modern smartphones and tablets are equipped with a variety of sensors including accelerometers, gyroscopes, pressure gauges, light and GPS sensors. Additionally, the devices become computationally powerful which allows for real-time processing of data gathered by their sensors. Universal access to the Internet via WiFi hot-spots and GSM network makes mobile devices perfect platforms for ubiquitous computing. Although there exist numerous frameworks for context-aware systems, they are usually dedicated to static, centralized, client-server architectures. There is still space for research in the field of context modeling and reasoning for mobile devices. In this paper, we propose a lightweight context-aware framework for mobile devices that uses data gathered by mobile device sensors and performs on-line reasoning about possible threats based on the information provided by the Social Threat Monitor system developed in the INDECT project. 相似文献
50.