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51.
Hao Chen Roman Kuziak Sybrand van der Zwaag 《Metallurgical and Materials Transactions A》2013,44(13):5617-5621
Cyclic phase transformation experiments are performed in a series of Fe-C-xMn, Fe-C-Mn-xNi, and Fe-C-Mn-xCo alloys to study the effect of alloying elements on the length of the stagnant stage during a cyclic partial phase transformation in the austenite–ferrite two-phase region. The length of stagnant stage increases linearly with the increasing Mn or Ni concentration, while Co has no effect. It was experimentally proven that the effects of alloying elements on the length of stagnant stage are additive, and the experimental results matched the predictions of the local equilibrium model very well. 相似文献
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53.
Bernhard Atorf Simon Friesen Roman Rennerich Holger Mühlenbernd Thomas Zentgraf Heinz Kitzerow 《Polymer Science Series C》2018,60(1):55-62
A switchable metasurface composed of plasmonic split ring resonators and a polymer-stabilized liquid crystal blue phase is developed. Owing to field-induced birefringence (electro-optic Kerr effect), the state of polarization of the incident near infrared radiation changes, when a voltage is applied to the liquid crystal. Thus, different resonant modes of the split ring resonators can be addressed and the transmission spectrum changes accordingly. In comparison with other liquid crystal phases, blue phases have several advantages. For example, they are optically isotropic in the field-off state, so that no alignment layer is required. The results of the present study indicate that the advantages of these mesophases can be utilized for switchable metasurfaces. 相似文献
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55.
Ozan Nazim Ciftci Roman Przybylski Magdalena Rudzinska Surya Acharya 《Journal of the American Oil Chemists' Society》2011,88(10):1603-1610
The composition and content of lipids, fatty acids, triacylglycerols, tocopherols and sterols in nine fenugreek genotypes
were analyzed. Lipid content in fenugreek seeds ranged from 5.8 to 15.2%. Major fatty acids were: linoleic acid (45.1–47.5%),
α-linolenic (18.3–22.8%), oleic (12.4–17.0%), palmitic (9.8–11.2%) and stearic (3.8–4.2%) acids. The ratios of n-6 to n-3
fatty acids were between 2.1 and 2.7. Similar fatty acid distribution was observed in all analyzed samples with some deviations.
α-Tocopherol was the predominant component found in the fenugreek lipid antioxidants, and it constituted over 84% of the total
amounts of tocopherols. It amounts ranged from 620 to 910 mg/kg lipids. β-Sitosterol was the major sterol in all samples,
varying from 14,203 to 18,833 mg/kg of lipids. Campesterol and cycloartenol were other major sterols, and these compounds
including β-sitosterol constituted 56–72% of all sterols. Fenugreek seed lipids consisted predominantly triunsaturated (56.9–66.5%)
and diunsaturated (32.2–41.6%) triacylglycerides. Among these components trilinolein (LLL; 12.9–20.5%) dominated followed
by PLL (14.0–20.4%), LnLnO (7.8–17.7%), PLO (5.7–11.6%), OLL (6.9–10.6%), LLLn (3.2–9.6%), and LnLnL (3.5–7.6%). Results of
the study show that fenugreek seed lipids may be a source of a nutraceutical ingredient for food applications. 相似文献
56.
Jianliang Lin William D. Sproul John J. Moore Roman Chistyakov Bassam Abraham 《Surface & coatings technology》2011,206(7):1780
The paper presents the results on the deposition of nanoscale structurally laminated CrN films using a novel multi pulse modulated pulsed power (MPP) magnetron sputtering technique. With the multi pulse MPP approach, thin films with a structural modulation in the nanometer range are obtained by alternately switching two (or even more) high power MPP pulses on the same target, which have different pulse lengths, frequencies and powers. Each pulse was turned on for a pulse repeat duration during which this given pulse shape was repeated. In this study, CrN films have been deposited in a closed field unbalanced magnetron sputtering system using the multi pulse MPP technique by varying the pulse repeat duration of two different pulses. The CrN films were also deposited by dc magnetron sputtering (dcMS) and single pulse MPP techniques for comparison. The microstructure and properties of the films were characterized using glancing incident X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nanoindentation, and ball-on-disk wear tests. The structure and properties of the multi pulse MPP CrN films depended on the pulse repeat duration. The highest hardness of 30.5 GPa and an H/E ratio of 0.9 have been achieved in the multi pulse MPP CrN films. The wear rate of the single pulse MPP and multi pulse MPP CrN films decreased by a factor of 5.8–17 as compared to the dcMS CrN films. 相似文献
57.
Lucjan Chmielarz Piotr Kuśtrowski Marek Drozdek Małgorzata Rutkowska Roman Dziembaj Marek Michalik Pegie Cool Etienne F. Vansant 《Journal of Porous Materials》2011,18(4):483-491
SBA-15 mesoporous silicas modified with rhodium were studied as catalysts for the N2O decomposition reaction. Rhodium was deposited on SBA-15 by the Molecular Designed Dispersion (MDD) method using Rh(acac)3 as a precursor of active phase. The same method was used for the deposition of Cu, Fe, Al and Ti. The SBA-15 support modified
with metals were characterized with respect to metal loading (EPMA), structure (XRD), texture (BET), morphology (SEM), Rh
dispersion (oxygen chemisorption), surface acidity (pyridine adsorption) and chemical nature of introduced copper and iron
species (UV–vis-DRS). The rhodium-containing SBA-15 samples were found to be active catalysts for the N2O decomposition reaction. Deposition of Al on the Rh-loaded catalyst increased its activity. An opposite effect was observed
for the samples modified with Cu and Fe. 相似文献
58.
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60.
Tatyana Petrova Natasha Vaklieva-Bancheva Simeon Darakchiev Roman Popov 《Clean Technologies and Environmental Policy》2014,16(7):1381-1392
In the present work, we carry out evaluation of gas flow maldistribution in different types of gas distributing devices (GDD) and packings by using experimental data for the output velocity profiles for both the absorption pilot column and industrial column. Two GDD construction types—with circular and with local tube gas feed, together with their modifications—are investigated. Two pilot columns—with random packing RSRM 1.5″ and with structured ceramic Honey-comb packing, and one industrial contact economizer with Honey-comb and inclined rings—have been studied. Six types of quantitative estimations of GDD and packings maldistribution are determined by the help of MATHCAD. Then, their sensitivity toward several factors, such as the type of GDD and packing, the initial gas flow velocity, the number and dimension of measuring cells on the column cross-section, the measurement error, and so on, is investigated. It is found that only two of the quantitative maldistribution estimations take into account the formation of maldistribution clusters, which deteriorates the uniform gas distribution. A novel method for quantitative determination of these clusters and also for identification of the zones at column cross-section, in which they appeared, has been developed. It is established that the measurement error and the dimension of measuring cell deeply influence the number, the area, and spatial distribution of these zones on the cross-section, as well as the values of maldistribution estimates. 相似文献