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991.
Rocio Velázquez Alejandro Hernández Alberto Martín Emilio Aranda Gustavo Gallardo Teresa Bartolomé Maria G. Córdoba 《International Journal of Food Science & Technology》2014,49(3):830-839
Several quality parameters of smoked, oven‐dried and sun‐dried paprikas were studied. Smoked paprikas showed the highest American Spice Trade Association (ASTA) units and pigment concentrations, whereas oven‐dried paprikas showed the best browning index and red/yellow pigment ratio, and sun‐dried paprikas had the highest redness for reflected colour. The colour stability results showed drastic overall colour change (ΔE) and decreased redness and ASTA units of the sun‐dried and oven‐dried paprikas after two and 5 days of UV exposure. Degradation of the smoked paprika colour parameters was progressive, and they showed less degradation even after 30 days. The evaluation of the antioxidant activity showed higher DPPH radical‐scavenging capacity in the smoked samples. The profiles of volatile phenolic compounds of the smoked samples are responsible for the differences in the antioxidant capacity. The great differences in colour stability and antioxidant activity make smoked paprika the best choice for use in the food industry. 相似文献
992.
《Ceramics International》2017,43(12):9128-9132
Continuous SiC fibers (SiC-CVC fibers) with low oxygen content (~2 wt%) were prepared by pyrolysis of polycarbosilane (PCS) fibers cured with chemical vapor curing (CVC). PCS fibers were cured by cyclohexene vapor as curing agent. Their structure and properties were compared with those of SiC fibers obtained from electron beam irradiation curing (SiC-EB fibers). SiC-CVC fibers were similar to SiC-EB fibers, with distinctly better thermomechanical stability than that of fibers cured by thermal oxidation curing (commercial KD-I fibers). CVC is a more economical and practicable approach for preparing high-performance SiC fibers than other strategies. 相似文献
993.
J. Wang 《International journal of control》2017,90(9):1846-1860
For zooming-out/in method used in the design of quantised feedback systems, the property of the duration of zoom-out mode (this duration is defined as capture time) is essential to input-to-state stability (ISS) of systems. This paper shows that a necessary and sufficient condition of achieving ISS with respect to external disturbances for quantised feedback systems is that capture time under the proposed coding scheme is uniformly bounded. It further shows that the coding scheme under which capture time is only bounded and not uniformly bounded cannot guarantee ISS of systems. A coding scheme is designed for uniformly bounded capture time and therefore achieves ISS of systems. 相似文献
994.
The effect of processing protocol on physical stability and the microstructure of water‐in‐oil‐in‐water multiple emulsions containing a mixture of two amphiphilic copolymers with opposed hydrophilic‐lipophilic balance as emulsifiers and a green solvent, 2‐ethylhexyl lactate, as the dispersed phase, has been assessed. Emulsions were obtained in at least two steps: a homogenization step by using a rotor‐stator device, followed by one or two homogenization steps carried out in a high‐pressure device that used microfluidizer technology. To study the microstructure and physical stability of these emulsions, a combination of different techniques, such as transmitted‐light optical microscopy, globule size distribution, viscous flow tests, and multiple light scattering measurements, were performed. 相似文献
995.
996.
《Intermetallics》2017
Ti-44Al-5Nb-1W-1B with a near lamellar microstructure was exposed at 700 °C for up to 10000 h in air. The changes in microstructure were investigated using scanning and transmission electron microscopy. It has been found that the combined addition of Nb and W can restrict parallel decomposition of α2 lamellae into ultrafine γ lamellae, but causes prevalent precipitation of fine β(B2+ω) particles from α2 lamellae and precipitation/growth of ω particles from β(B2) grains. However, although 3/4 of α2 lamellae dissolved and majority of them transformed to β(B2+ω), tensile ductility is reduced only by 30% while the strengths remain essentially unchanged for the thermally exposed alloy. This is attributed to the widespread distribution of β(B2+ω) particles. On the other hand, fatigue limit was found to decrease during the first 5000-h exposure but finally increased by 11% after 10000-h exposure. The reasons for the decrease and increase of fatigue strength at different exposure stages are discussed by considering two contradictory effects on the exposed alloy: 1) exposure-induced embrittlement due to microstructural changes (harmful); 2) annealing of fatigue samples in a warm air environment for prolonged time (beneficial). 相似文献
997.
A novel intramolecular charge transfer (ICT) based blue fluorophor, 5,11-di(40-dimesitylboronphenyl)indolo[3,2-b]carbazole(DDBICZ), possessing a high fluorescent quantum yield of 0.52, a high triplet energy level (2.59 eV), and an intriguing bipolar charge transporting ability, was used as a highly efficient blue fluorophor and a host for a yellow phosphor. Doping a yellow phosphor(bis(2-(3-trifluoromethyl-4-fluorophenyl)-4-methylquinolyl)(acetyl-acetonate)iridium(III) (Ir(ffpmq)2(acac)) in the host DDBICZ, a simplified fluorescence/phosphorescence (F/P)-based hybrid white organic light-emitting diode (WOLED) with a symmetrical BYB-EML of DDBICZ (10 nm)/DDBICZ: 6 wt% Ir(ffpmq)2(acac) (10 nm)/DDBICZ (10 nm) is demonstrated. The hybrid WOLED exhibits excellent high color stability and good color quality. Under wide operating voltage range from 5 V to 10 V, the Commission Internationale de L'Eclairage (CIE) coordinates of the hybrid WOLED only change from (0.35, 0.36) to (0.34, 0.35), with a high color rending index (CRI) of 79–81. The high color stability is due to the fact that the BYB-EML effectively offsets the change of emission intensity from different emitters caused by the shift of carrier recombination zone with the increase of voltage. In addition, the hybrid WOLED also reveals a considerable current efficiency of 24.4 cd/A. These results demonstrate that efficient F/P hybrid WOLEDs with high color stability could be achieved by such simple BYB-EML structure using single-dopant strategy. 相似文献
998.
Strain-induced martensitic phase transformation and its influence on the formability of newly developed nitrogen-alloyed metastable austenitic stainless steels were systematically investigated. Yield strength for the asreceived steels bearing lownickel content was around 300 MPa and their elongation ratios varied from 55. 2% to61. 7%. Erichsen numbers of these samples differed from 13. 82 to 14. 57 mm. Although its Cu content was lower than that of other samples,steel D2 exhibited better plasticity and formability,which was attributed to γ→α'martensitic phase transformation. EBSD,XRD,and magnetism tests showed that increases in deformation ratio gradually increased the α' martensite phase of a sample,thereby contributing to its strain and inducing the optimal transformation-induced plasticity effect. An M_(d30/50) temperature of around 20 ℃,which is close to the deformation temperature,provided the austenite with adequate stability and gradually transformed it into martensite,thereby endowing lean ASS with better formability. 相似文献
999.
We report on the fabrication of the poly{[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]} (PTB7) and poly{[N,N-9-bis(2-octyldodecyl)- naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,59-(2,29-bithiophene)}(P(NDI2OD-T2)) active layer combination employing air brush spray coating technique in 2-methyl anisole. Optical absorption characteristics of the blend layer were examined utilizing UV–visible spectra in the wavelength sweep varying from 300 to 900 nm. Atomic force microscopy was utilized to analyze the surface characteristics of the fabricated active layer. Under the radiance of simulated solar light with 100 mW cm−2 (AM 1.5G), the current density voltage (J-V) characteristics were determined by employing a solar simulator. Fullerene-free organic solar cells were build using a combination of P(NDI2OD-T2) acceptor and a polymer donor PTB7 with SnO2 acting as an interlayer, which showed power conversion efficiency (PCEs) of more than 7.0%, which is considered as the best PCEs been reported for the chosen donor and the acceptor. The device is extremely stable, holding 75% of its unique effectiveness subsequent to being put away in air for 72 days even without encapsulation. These outcomes demonstrate that the spray-coated film is a feasible contrasting option to the vacuum-deposited ITO film in terms of cost for mass production and for roll-to-roll based organic solar cells. 相似文献
1000.
以去除水分的新鲜山核桃坚果为原料,经~(60)Coγ射线分别在0、0.8、2.0、5.0、8.0 k Gy剂量下辐照处理,然后置于温度(2±0.5)℃、湿度(RH)70%~80%的环境中密闭贮藏。期间对山核桃果肉主要营养成分(粗脂肪、粗蛋白质、油中脂肪酸、维生素E),氧化稳定性(酸值、过氧化值、O~-_2·生成速率、氧化诱导温度、氧化诱导时间)的动态变化进行跟踪监测。结果表明:5.0、8.0 k Gy辐照处理显著加剧了山核桃贮藏期间酸值、过氧化值、O~-_2·生成速率的升高,降低了粗脂肪、不饱和脂肪酸和维生素E含量,降低了氧化诱导温度和氧化诱导时间;与对照组及其他辐照组相比,2.0 k Gy剂量组较好地在贮藏期间保持了不饱和脂肪酸及维生素E含量,对山核桃氧化稳定性影响较小,有助于保持山核桃营养和延长山核桃贮藏期。 相似文献