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741.
Near-field optical properties and surface plasmon effects in a silver-shell nanocylinder pair with five different dielectric holes (DHs) that interact with a transverse magnetic mode incident plane wave are simulated by use of the finite-element method, which includes the investigation of particle-particle interaction. The proposed structure exhibits a redshifted localized surface plasmon that can be tuned over an extended wavelength range by varying the dielectric constant in DHs and the thickness of the nanocylinder silver shell. The increase in the near-field intensity is attributed to a larger effective size of DH that is filled with a higher refractive medium. 相似文献
742.
743.
Halime Pehlivanoğlu Mehmet Demirci Omer Said Toker Nevzat Konar Salih Karasu Osman Sagdic 《Critical reviews in food science and nutrition》2018,58(8):1330-1341
Oils and fats are widely used in the food formulations in order to improve nutritional and some quality characteristics of food products. Solid fats produced from oils by hydrogenization, interesterification, and fractionation processes are widely used in different foodstuffs for these aims. In recent years, consumer awareness of relation between diet and health has increased which can cause worry about solid fat including products in terms of their high saturated fatty acid and trans fatty acid contents. Therefore, different attempts have been carried out to find alternative ways to produce solid fat with low saturated fatty acid content. One of the promising ways is using oleogels, structuring oils with oleogelators. In this review, history, raw materials and production methods of the oleogels and their functions in oleogel quality were mentioned. Moreover, studies related with oleogel usage in different products were summarized and positive and negative aspects of oleogel were also mentioned. Considering the results of the related studies, it can be concluded that oleogels can be used in the formulation of bakery products, breakfast spreads, margarines, chocolates and chocolate-derived products and some of the meat products. 相似文献
744.
Ayla Kaya Betul Demirci Suleyman Doğu Muhittin Dinç 《International Journal of Food Properties》2017,20(11):2639-2644
The genus Stachys L. one of the largest genera of Lamiaceae and Stachys species are used by many people for the therapeutic value of their essential oils. In this study, water-distilled essential oil of three species of Stachys was analysed. The analysis was performed by using gas chromatography-flame ionisation detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS) systems simultaneously. The major components found were hexadecanoic acid (23.7%), dodecanoic acid (11.3%), and caryophyllene oxide (10.7%) for S. sericantha P.H. Davis (endemic); α-pinene (53%), β-pinene (8.2%) for S. gaziantepensis M. Dinc and S. Do?u (endemic); Menthyl acetate (15.3%), isomenthone (15.0%), pulegone (10%), spathulenol (7.0%), and caryophyllene oxide (6.7%) for S. mardinensis (Post) R. Mill. 相似文献
745.
746.
Der-Rong Din Chi-Yen Hung Yu-Cyuan Chen Hung-Yin Wang Chung-Yang Tu 《Photonic Network Communications》2012,23(1):40-52
In this article, for the given wavelength division multiplexing (WDM) network, the demand traffic matrix, the old and new survivable virtual topologies which are protected by the failure-independent path-protecting p-cycles (FIPP p-cycles) protection scheme, the virtual topology transition sequence (VTTS) problem is studied. The goal of this problem is to find an optimal sequence to transfer the old virtual topology into
new one, and during the transiting process, the services are not disrupted. Moreover, each lightpath in the virtual topology
is protected by the FIPP p-cycle and can survive against a single-link failure. In this article, a heuristic algorithm and
a genetic algorithm are proposed to solve this problem. Simulations are also performed to evaluate the performance of proposed
algorithms. 相似文献
747.
Superabsorbent copolymer hydrogels were prepared by gamma irradiation of aqueous solutions of 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS) and 2‐dimethyaminoethyl methacrylate (DEMA) monomers mixtures. The thermal stability of hydrogels was evaluated by thermogravimetric analysis. The ability to adsorb Cu2+ ions and dyes by the prepared hydrogels from aqueous solutions was investigated. The swelling study, in water, showed that the hydrogels based on pure AMPS monomer and AMPS/DEMA copolymers reached the equilibrium state after 6 h. However, the hydrogel based on pure AMPS monomer showed higher swelling than the copolymer hydrogels based on AMPS/DEMA. It was found that the copolymer hydrogels based on different compositions showed affinity to absorb Cu2+ metal ions as well as basic and acid dyes; however, this affinity was found to decrease with increasing the ratio of DEMA in the initial feeding solutions. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers 相似文献
748.
The concentrations of the natural radionuclides (226)Ra, (232)Th and (40)K in 15 different water samples from Elba protective area, south-eastern desert of Egypt, have been determined using NaI(Tl) detector. Gamma ray spectrometric analysis was performed and the concentrations obtained for each of the radionuclides expressed in Bq l(-1) ranging from 1.6 to 11.1 for (226)Ra, 0.21 to 0.97 for (232)Th and 9.1 to 23 for (40)K. A reasonable correlation was found between (226)Ra, (232)Th concentrations and pH, although no general trend was observed with conductivity and total dissolved solids. The mean effective doses of 0.56 mSv y(-1) for (226)Ra, 0.065 mSv y(-1) for (232)Th and 0.04 mSv y(-1) for (40)K were estimated for the ingestion of these waters by adults. 相似文献
749.
微量Co对MoSi2机械合金化材料性能的影响 总被引:1,自引:1,他引:1
在氩气保护下 ,利用机械合金化的方法制备了MoSi2 、MoSi2 0 5 %Co和MoSi2 1 0 %Co(质量分数 ) 3种粉末 ,经过冷压烧结制成实验样品 ,研究了微量Co对MoSi2 材料性能的影响。结果表明 ,微量Co可以明显改善MoSi2 的室温断裂韧性和抗弯强度 ,其中w(Co) =1 0 %的MoSi2 合金的抗弯强度、断裂韧性可以分别达到 5 88MPa、9 2 7MP·m1/ 2 ,两项指标均高于国内同种工艺制备的商用MoSi2 的性能指标。 相似文献
750.
Developing new software quickly, successfully, and at low cost is critical in organizations. Ways of assessing the effectiveness of development teams has highlighted measures of factors, such as teamwork, group cohesiveness, and team integration, but the use of group potency theory (the collective belief of a group that it can be effective) is rare. In our study, we investigated antecedents of and consequences to group potency in software development project teams. By examining 53 software development project teams collected from small and medium-sized software firms in Turkey, we found, that team potency positively affected speed-to-market, development cost, and market success of the product. We also found that trust among project team members, past experiences of the members, and team empowerment had a positive impact on the team potency during the project. Managerial and theoretical implications are discussed. 相似文献