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1.
Effects of different drying methods and different addition levels of eggplant (EP) on product quality of low-fat patties (LFPs) were investigated during storage. EP was dried in an oven dryer at 60 °C or a freeze dryer at −50 °C. LFPs were prepared by replacing with 1.5% soy protein isolate (SPI). Six treatments were used in this study: (1) control (CTL), without addition of EP; (2) reference (REF), 0.1% ascorbic acid; (3) O1, 0.25% oven-dried (OD) EP; (4) O2, 0.5% ODEP; (5) F1, 0.25% freeze-dried (FD) EP; and (6) F2, 0.5% FDEP. Redness (a*) and lightness (L*) values in LFPs added with EP were lower than those of others (p < 0.05) and decreased with increasing storage time. Yellowness (b*) values of cooked patties were increased during storage time (p < 0.05), with control having the highest value. The addition of EP or ascorbic acid into LFPs lowered microbial counts than control (p < 0.05). Thiobarbituric acid reactive substances (TBARS) was increased during storage, with REF having the lowest value, and patties added with EP had lower TBARS values than control during storage. Volatile basic nitrogen (VBN, mg%) contents of all patties also increased during storage time with O2 and F2 having lower values than control. Therefore, EP might have potential as a natural antioxidant in meat products during storage.  相似文献   
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Heavy water or deuterium oxide (D2O) comprises deuterium, a hydrogen isotope twice the mass of hydrogen. Contrary to the disadvantages of deuterated perovskites, such as shorter recombination lifetimes and lower/invariant efficiencies, the serendipitous effect of D2O as a beneficial solvent additive for enhancing the power conversion efficiency (PCE) of triple-A cation (cesium (Cs)/methylammonium (MA)/formaminidium (FA)) perovskite solar cells from ≈19.2% (reference) to 20.8% (using 1 vol% D2O) with higher stability is reported. Ultrafast optical spectroscopy confirms passivation of trap states, increased carrier recombination lifetimes, and enhanced charge carrier diffusion lengths in the deuterated samples. Fourier transform infrared spectroscopy and solid-state NMR spectroscopy validate the N–H2 group as the preferential isotope exchange site. Furthermore, the NMR results reveal the induced alteration of the FA to MA ratio due to deuteration causes a widespread alteration to several dynamic processes that influence the photophysical properties. First-principles density functional theory calculations reveal a decrease in PbI6 phonon frequencies in the deuterated perovskite lattice. This stabilizes the PbI6 structures and weakens the electron–LO phonon (Fröhlich) coupling, yielding higher electron mobility. Importantly, these findings demonstrate that selective isotope exchange potentially opens new opportunities for tuning perovskite optoelectronic properties.  相似文献   
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Silicene, a new 2D material has attracted intense research because of the ubiquitous use of silicon in modern technology. However, producing free-standing silicene has proved to be a huge challenge. Until now, silicene could be synthesized only on metal surfaces where it naturally forms strong interactions with the metal substrate that modify its electronic properties. Here, the authors report the first experimental evidence of silicene nanoribbons on an insulating NaCl thin film. This work represents a major breakthrough, for the study of the intrinsic properties of silicene, and by extension to other 2D materials that have so far only been grown on metal surfaces.  相似文献   
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Whole body saline-perfused rainbow trout (Oncorhynchus mykiss) was ice-stored for 4 weeks and compared with unwashed/washed minces from unbled and bled trout in terms of rancid odour, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and redness loss. Muscle from saline-perfused fish, which had 72% less total haem, was deficient in rancid odour during the whole storage, while bled (54% less haem) and unbled samples developed rancid odour already after ~4 and 2 days; higher intensity without bleeding. PV/TBARS also developed in the order unbled > bled > perfused samples; however, PV/TBARS were not as completely prevented as rancid odour after perfusion. Saline washing (3 × 3 volumes) of unbled mince removed 84% haem and yielded the second most stable sample while saline washing (1 × 1 volumes) destabilised unbled mince, despite 64% haem removal. Concurrent antioxidant removal during washing of minces obviously counteracted the effect of blood removal and washing fish mince with small volumes of solution should be used with great care.  相似文献   
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The influence of boric acid (BA) and borax (BO) neutron-absorbing fillers on thermal stability and viscoelastic behavior of natural rubber (NR) low-density polyethylene composites has been studied. The thermal degradation and dynamic mechanical properties of the composites have been analyzed as a function of temperature. The results revealed the enhancement of thermal stability of the composites by the addition of BA and BO fillers. The flame resistance of the material was improved by the addition of both the fillers. The storage modulus was found to be dependent upon the temperature and nature of the filler. The amount of NR chains immobilized by filler particles has been quantified from dynamic mechanical analysis and secondary filler/filler interactions have been verified by the Payne effect analysis. Finally, the experimental results have been compared with theoretical predictions.  相似文献   
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Obtaining strong interfacial interaction between filler and polymer matrix is very crucial for the fabrication of polymer nanocomposites with superior performance. Present study is aimed to fabricate high performance styrene butadiene rubber (SBR) nanocomposites with imidazolium type ionic liquid modified multiwalled carbon nanotube (MWCNT). Ionic liquid facilitates the dispersion of MWCNT in rubber matrix and it is obvious from transmission electron microscopy images. Diffusion of toluene through SBR nanocomposite membranes has been investigated as a function of surface modified MWCNT (f-MWCNT) content to analyze the chain dynamics and filler-polymer interactions. O2 gas barrier effect of nanocomposites with special reference to the filler loading is explored. The substantial improvement in the barrier effect in presence of filler interpreted on the grounds of a theoretical model describing permeability of heterogeneous systems. Finally solvent sensing characteristics of prepared nanocomposites are also analyzed and it is observed that prepared nanocomposites can be used as a flexible solvent sensor.  相似文献   
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Journal of Superconductivity and Novel Magnetism - Crystalline ZnO offers an excellent host matrix to create a dilute magnetic semiconductor (DMS) owing to its facile Zn-atom substitution with the...  相似文献   
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