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排序方式: 共有547条查询结果,搜索用时 10 毫秒
61.
The aim of this study was to investigate the effect of Gundelia tournefortii L. leaves and G. tournefortii L. milk as a new natural stabiliser on the quality characteristics of ice cream. For this aim, G. tournefortii L. leaves were added to an ice cream mix at three different concentrations (0.6, 1.0 and 3.0% w/w), and also, its milk was used as a stabiliser at 0.6% w/w concentration for ice cream production. Certain physical and sensorial characteristics of ice creams were compared with those of some commercial food gums such as guar gum, carrageenan and salep. Also, the chemical structure of G. tournefortii L. milk was determined using infrared spectra and elemental analyses. In comparison with commercial stabilisers, G. tournefortii L. did not display a notable effect on quality characteristics (viscosity, overrun, first dripping times and complete melting times). However, when considering these quality characteristics, the values for G. tournefortii L. milk were close to the values obtained for the commercial gums. In terms of sensorial characteristics, all the concentrations of G. tournefortii L. leaves were given low scores by panellists compared to the commercial stabiliser. However, G. tournefortii L. milk was given scores similar to the commercial stabiliser. 相似文献
62.
Hatice Begüm Murathan Gülay Özkan Meryem Sena Akkuş Derya Öncel Özgür Göksel Özkan 《International Journal of Hydrogen Energy》2018,43(23):10728-10733
The aim of this study is to enable high hydrogen production yield from catalytic methanolysis of ammonia borane (AB) in the presence of a cordierite type ceramic monolithic. The monolithic channel surfaces were coated with Al2O3 by wash-coating method and then this layer was impregnated with 1 wt%Pd-2 wt%Co bimetallic catalyst. SEM-EDX and multi-point BET analysis were used in order to characterize the catalyst. The experimental studies were conducted in a continuous flow type reactor, which was used for the first time in this study. The reactions were carried on low temperature (40 °C), and with various AB feed concentrations and flow rates. It was found that the highest hydrogen production yield (88.5%) was obtained from AB flow rate of 3.3 mL/min, and AB feed concentration of 0.1 wt%. It was concluded that Pd-Co/Al2O3 coated monolithic, which is a stable, active and low-cost catalyst, was a very promising catalyst for on-board hydrogen production from the methanolysis of ammonia borane. 相似文献
63.
In this study, CO2 emissions of Turkish manufacturing industry are calculated by using the fuel consumption data at ISIC revision 2, four digit level. Study covers 57 industries, for the 1995–2001 period. Log Mean Divisia Index (LMDI) method is used to decompose the changes in the CO2 emissions of manufacturing industry into five components; changes in activity, activity structure, sectoral energy intensity, sectoral energy mix and emission factors. Mainly, it is found that changes in total industrial activity and energy intensity are the primary factors determining the changes in CO2 emissions during the study period. It is also indicated that among the fuels used, coal is the main determining factor and among the sectors, 3710 (iron and steel basic industries) is the dirtiest sector dominating the industrial CO2 emissions in the Turkish manufacturing industry. 相似文献
64.
Hydrogen is considered in many countries to be an important alternative energy vector and a bridge to a sustainable energy future. Hydrogen is not an energy source. It is not primary energy existing freely in nature. Hydrogen is a secondary form of energy that has to be manufactured like electricity. It is an energy carrier. Hydrogen can be produced from a wide variety of primary energy sources and different production technologies. About half of all the hydrogen as currently produced is obtained from thermo catalytic and gasification processes using natural gas as a starting material, heavy oils and naphtha make up the next largest source, followed by coal. Currently, much research has been focused on sustainable and environmental friendly energy from biomass to replace conventional fossil fuels. Biomass can be considered as the best option and has the largest potential, which meets energy requirements and could insure fuel supply in the future. Biomass and biomass-derived fuels can be used to produce hydrogen sustainably. Biomass gasification offers the earliest and most economical route for the production of renewable hydrogen. 相似文献
65.
Derya Unlu 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(24):3606-3611
Global warming is one of the biggest environmental problems of late. The use of renewable raw material resources as biomass and its conversion into alternative energy resources have attracted considerable attention during the recent years. Ethyl levulinate (EL) is a kind of fuel bioadditive for use in diesel and biodiesel engines, which is produced by the esterification of ethanol and levulinic acid. In the present study, sulfosuccinic acid (SSA) catalysts supported on chitosan catalytic membrane is used for the synthesis of EL. The effects of temperature, catalyst amount, and molar feed ratio were studied. 相似文献
66.
Hydrogen is believed to be the one of the main energy carriers in the near future. In this research glycerine, which is produced in large quantities as a by-product of biodiesel process, was converted to hydrogen aiming to contribute to clean energy initiative. Conversion of glycerol to hydrogen was achieved via aqueous-phase reforming (APR) with Pt/Al2O3 catalyst. The experiments were carried out in an autoclave reactor and a continuous fixed-bed reactor. The effects of reaction temperature (160-280 °C), feed flow rate (0.05-0.5 mL/dak) and feed concentration (5-85 wt-% glycerine) on product distribution were investigated. Optimum temperature for hydrogen production with APR was determined as 230 °C. Maximum gas production rate was found at the feed flow rates around 0.1 mL/min. It was also found that hydrogen concentration in the gas product increased with decreasing glycerol concentration in the feed. 相似文献
67.
68.
A. Sezai Sarac Murat Ates Elif Altürk Parlak 《Journal of Applied Electrochemistry》2006,36(8):889-898
Carbazole was electrochemically synthesized on carbon fiber microelectrodes (CFMEs) in different electrolyte and solvent media. The characterization of polycarbazole thin films formed on micron sized carbon fiber electrodes was performed by electrochemical methods (i.e., cyclic voltammetric measurements, solid state conductivity measurements (four point probe), spectrophotometric methods (ultraviolet/visible spectroscopy (UV–vis), ex situ spectroelectrochemistry, fourier transform infrared reflectance spectroscopy (FTIR-ATR)) and scanning electron microscopy (SEM). The best electrolyte and solvent in regards to yield, conductivity and charge for the electro-grafting was sodium perchlorate in acetonitrile, whose conductivity was 3.60 mS cm−1, had a yield of 89% and had a charge of 5.50C. The effects of scan rate, feed ratio, supporting electrolyte and solvent type on the electropolymerization are discussed. 相似文献
69.
This study examines the energy efficiency implications of a daily billed energy service, commonly known as ‘prepaid’ electricity, which is used by a growing percentage of residential customers in the competitive Texas electricity market. Our empirical analysis results suggest that this service could save 9.6% of average daily energy consumption, net of the effect of any disconnections. This quantitative study demonstrates that energy efficiency from prepaid energy products can extend to competitive marketplaces. 相似文献
70.
Relationship between structure and physical strength of silk fibroin nanofiber sheet depending on insolubilization treatment 下载免费PDF全文
Yasuhiro Fukuda Derya Aytemiz Akira Higuchi Yuya Ichida Tetsuo Asakura Tsunenori Kameda Yasumoto Nakazawa 《应用聚合物科学杂志》2017,134(48)
Materials such as expanded polytetrafluoroethylene and glutaraldehyde‐fixed bovine pericardium are currently used for cardiac tissue regeneration. However, patches made from these materials remain permanently without being absorbed by the body and must be replaced overtime because of degeneration or lack of growth. To improve the long‐term outcomes for cardiac tissue regeneration, biocompatible and biodegradable materials must be used. In this study, we used two biocompatible polymers, silk fibroin (SF), which is biodegradable and segmented polyurethane, to prepare nonwoven sheets that were then insolubilized by water vapor or methanol treatment. The tensile stress increased significantly on adding segmented polyurethane to pure SF and the water vapor processed sheets showed higher extension on strain than the methanol‐processed sheets. The different insolubilization treatments also resulted in different SF structures. Our results show that it is possible to obtain the physical properties required for cardiac tissue repair patch by varying the insolubilization treatment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45560. 相似文献