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51.
The effects of the use of antioxidant technology on the quality of mackerel burgers stored at 4 °C were investigated in terms of sensory, biochemical [thiobarbituric acid (TBA), total volatile basic nitrogen (TVB‐N), peroxide value (PV) and free fatty acids (FFA)] and microbiological analyses [total viable count (TVC)]. Fish meat was divided into three groups; the control (C) without rosemary extract, the second group with 0.4% rosemary extracts (Group A) and the third with 0.8% rosemary extracts (Group B). Results showed that the TVB‐N level did not exceed acceptability limit (30–35 mg 100 g?1) for all groups. TBA value for the control significantly increased from 1.47 to 4.80 MA kg?1 whereas it slightly increased in treatment groups as the storage time increased. Significantly higher PV and FFA (P < 0.05) were obtained from the control group. Rosemary extract, in combination with vacuum pack was effective in controlling the growth of bacteria and biochemical indices.  相似文献   
52.
In this study, we investigated the effects of microencapsulation conditions on product quality of pomegranate peel phenolics. Our results indicate an optimum air inlet temperature of 160 °C and 1/1 (w/w) or 1/3 (w/w) for phenolics/maltodextrin ratio. No differences were observed amongst the maltodextrins used for coatings. There were also no statistically significant differences in phenolic content of microcapsules for the storage periods of 90 days at 4 °C (p > 0.05). We also evaluated the resultant microencapsulated phenolics for enrichment of the functional properties of regular ice cream used as model food in our studies. Addition of pomegranate peel phenolics at 0.5 and 1.0% (w/w) showed significant improvement of the antioxidant and α-glucosidase inhibitory activities of the enriched ice creams compared with control sample. Antioxidant activity as EC50 and α-glucosidase inhibitory as IC50 of 1.0% phenolic enriched ice creams were 133.3 and 22.9 μg/mL, respectively. More than 75% of the panellists accepted the phenolic enriched ice creams in sensory evaluation, which lends supports to such products for commercial introduction to the general public with the potential as functional foods.  相似文献   
53.

Fixed-bed pyrolysis biooils of hazelnut (Corylus Avellana L.) bagasse have been identified for their structures. The condensed biooils were analyzed for their properties as fuels and compared with petroleum-derived products. The biooil was analyzed by Fourier Transform infrared spectroscopy (FTIR) and 1H-NMR spectra. The biooils were fractionated into pentane solubles and insolubles. Pentane solubles were then solvent fractionated into pentane, toluene and methanol subfractions by fractionated column chromatograpy. The aliphatic subfractions of the biooils were then analyzed by capillary column gas-liquid chromatography (GC). In addition, the physical properties, higher heating value and elemental analysis of the biooil were determined. The empirical formula of biooil that has a heating value of 34.57 MJ/kg was established as CH1.45O0.33N0.127. Chromatographic and spectroscopic studies on the biooil showed that the oil obtained from hazelnut bagasse could be used as a renewable fuel and chemical feedstock.  相似文献   
54.
Fuel properties of rapeseed oil and soybean oil methyl esters (e.g. density, cetane number and viscosity etc.) are similar to those of the diesel fuel. These methyl esters can be used as diesel engine fuel by mixing withy diesel fuel. In this study a comparison of diesel fuel, the rapeseed oil methyl ester and the soybean oil methyl ester was made from the engine performance and emissions point of view. The tests were carried out with a four-cylinder diesel engine for tree different injection pressures such as 250, 300 and 350 bar with each of these fuels. For the purpose of comparison, tests were also conducted at full load conditions with diesel fuel. As the result, the performance and emission values of rapeseed oil (R) and soybean oil (S) methyl esters were found to be nearly the same with those of diesel fuels (D) when injection pressure was increased to 300 bar.  相似文献   
55.
Abstract

In this article, the potential utilization of hazel nut shell as a combustible residue was studied. To obtain liquid and gaseous products, the hazel nut shell was subjected to pyrolysis and it was converted to 49.3 % (w) gaseous and 20.0 % (w) liquid products at 475 °C for 7.5 minutes in a simple pyrolysis device The kinetic model used in the present study was based on fractional weight loss for each pyrolysis step. The simple fast pyrolysis was compared with TGA technique.  相似文献   
56.
The Single Flying Capacitor Converter (SFCC) and Dual Flying Capacitor Converter (DFCC) are two-quadrant power supplies for energy storage and transfer systems. They have applications in nuclear research and pulsed power systems in which superconductive coils are used. In this paper analytical expressions for the time-averaged behaviours of SFCC and DFCC are derived by using averaging technique. Because large superconductive magnet coils are used, time constants of the switched circuits are large enough compared to the switching period. Therefore, an averaged PWM switch equivalent circuit is substituted into the original converter circuits to find the averaged system equations. With this new insight in the averaged dynamics, their design and control can be optimized. Although DFCC has less coil current ripple compared to SFCC, the analysis will show that the averaged behaviours of both converters are the same.  相似文献   
57.
Laminated composites with ceramic front layers and metallic or composite backing layers have gained attractiveness as lightweight armours, as they exhibit the same ballistic performance with lower areal densities as compared to steels. Drop-weight testing (DWT) has potential for evaluating the low velocity impact behaviour of materials. This testing gives significant ideas and information about failure mechanisms and behaviour of materials under low velocity impact. In this study, DWT of alumina/aluminum laminated composites was done in order to investigate the effects of lamination type, density with respect to area and mechanical property of backing material on the low velocity ballistic performance of these composites. The experimental results showed that the laminated composite with ceramic front layer and aged-aluminum alloy as backing layer was the most effective among different investigated specimens against low velocity impact loads.  相似文献   
58.
The usage of ultrasound has gained popularity in the recent years. Ultrasonic processing means blasting liquids, usually water, with very intense sound at high frequency, producing very well mixed powerful chemical and physical reactions. This paper deals with the investigation of the effect of ultrasonic energy on the conversion fraction of sulfur in the production reaction of sodium thiosulfate which was obtained from sulfur and Na2SO3 solution. Concentration of Na2SO3 solution parameter was chosen as the constant parameter. The experiments were performed with various amplitudes of ultrasound power and in the absence and presence of ultrasound energy in various temperatures with various particle sizes. The results indicate that the conversion fraction values increase in the presence of ultrasound energy and increase at high amplitude values.  相似文献   
59.
Recent studies have pointed to the heptamethylbenzenium cation as a prominent intermediate in the methanol to hydrocarbons (MTH) reaction. The reactions of the heptamethylbenzenium cation in a H-beta zeolite was studied at 300 °C by feeding its corresponding base (WHSV = 0.4 h?1). The reactant was converted completely into aliphatic products, polymethylbenzenes and coke under the employed conditions. The results testify that the proposed reaction intermediate yields the same product spectrum as methanol. The composition of the material retained in the catalyst micropores after 15 min of reaction was determined by dissolving the catalyst in 15% HF. Polymethylated benzenes (predominantly pentamethylbenzene), dihydro-trimethylnaphthalenes, and hexamethylnaphthalene were the major components. The results also support the idea that the lowest naphthalene derivative is formed from the heptamethylbenzenium cation by a molecular rearrangement. Hence, the heptamethylbenzenium cation is inherently linked to both product formation and catalyst deactivation in the MTH reaction.  相似文献   
60.
In this paper, in addition to the universal 4-port mutator circuit introduced earlier with an adder and a subtractor block, two more 4-port mutator circuits, one with plus type (CCII+) and minus type current conveyors (CCII?), the other with a plus type current conveyor (CCII+) and one minus type current follower (CF?) are presented, their port relation matrix and their realization of different memstors are tabulated. How the transfer characteristics of the ideal mutative 4-ports with respect to frequency hold is verified using their transistor level simulations. By terminating properly two ports of the mutative 4-port simulations of a memristor with three different mutators, of a meminductor and of a memcapacitor are presented and compared also with some mutators existing in the literature.  相似文献   
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