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21.
Franco Ferrero Monica PeriolattoGiorgio Rovero Mirco Giansetti 《Journal of Cleaner Production》2011,19(12):1377-1384
Dyeing processes of various yarns (wool, cotton, polyester, nylon 6 and acrylic) were studied with the aim to substitute some auxiliary agents with ethanol at low concentration. The results observed in isothermal dyeing showed a favorable effect of alcohol addition, at about 1-3% v/v, on the dye uptake, with some differences depending on fiber nature and dye class. This effect was correlated with contact angle measurements of water-ethanol solutions on the mentioned yarns, which confirmed a lower surface tension in the same concentration range. Then, laboratory tests with dye triads at programmed temperature were carried out comparing the results of standard dyeing recipes with those obtained by replacing wetting, retardant and leveling agents with ethanol. Good color imitations were generally shown with respect to standard processes. A wetting effect of ethanol was shown for all the tested yarns and dye classes, while in wool dyeing with acid, pre-metallized and reactive dyes, ethanol was suitable to replace also leveling and retarding agents. Light and wash fastnesses were also compared. Finally the environmental benefits arising from chemical substitution of auxiliary agents with ethanol were highlighted and the cost of alcohol introduction was compared with the cost saving of auxiliary substitution. A positive economic balance was obtained. 相似文献
22.
Kevin J. McGraw Elizabeth A. Tourville Michael W. Butler 《Behavioral ecology and sociobiology》2008,62(12):1991-2002
Interest in animal carotenoids, especially in birds, has exploded in recent years, and so too have the methods employed to
investigate the nature and function of these pigments. Perhaps the most easily and commonly performed procedure in this work
has been the determination of carotenoid concentration from avian plasma. Over the past 20 years of research on avian carotenoids,
numerous methods have been used to extract carotenoids from bird plasma, all of which have differed in several important parameters
(e.g., number and types of solvents used, degree of mixing/centrifugation). However, to date, no study has systematically
compared these methods to determine if any of them are more effective than others for recovering any or all types of carotenoids
present. We undertook such an investigation on plasma samples from two bird species (house finch, Carpodacus mexicanus, and mallard, Anas platyrhynchos) using five of the most commonly employed methods for extracting carotenoids from avian plasma: (1) acetone-only, (2) methanol-only,
(3) ethanol-only, (4) ethanol + hexane, and (5) ethanol + tert butyl methyl ether. We also manipulated the amount of time that extracts were centrifuged, which has varied tremendously
in previous studies, to evaluate its importance on carotenoid recovery. We found that all methods equally recovered the polar
xanthophylls (lutein and zeaxanthin), but that the methanol-only procedure poorly recovered non-polar carotenoids (less β-carotene
in both species and less β-cryptoxanthin in house finches) compared to the other methods. These results suggest that the data
accumulated to date on xanthophyll plasma carotenoids in birds should be comparable across studies and species despite the
different chemical extraction methods used. However, care should be taken to use relatively strong organic solvents for fully
recovering non-polar carotenoids. We also found no effect of centrifugation duration (1 vs. 10 min at 10,000 rpm) on carotenoid
recoveries, demonstrating that researchers can save considerable time by centrifuging for a much shorter time period than
is typically used. 相似文献
23.
M. Tayyeb Javed W. Nimmo Asif Mahmood Naseem Irfan 《Journal of environmental management》2009,90(11):3429-3435
An experimental investigation was performed to study the effect of oxygenated liquid additives, H2O2, C2H5OH, C2H4(OH)2 and C3H5(OH)3 on NOx removal from flue gases by the selective non-catalytic reduction (SNCR) process using urea as a reducing agent. Experiments were performed with a 150 kW pilot scale reactor in which a simulated flue gas was generated by the combustion of methane operating with 6% excess oxygen in flue gases. The desired levels of initial NOx (500 ppm) were achieved by doping the fuel gas with ammonia. Experiments were performed throughout the temperature range of interest, i.e. from 800 to 1200 °C for the investigation of the effects of the process additives on the performance of aqueous urea DeNOx. With H2O2 addition a downward shift of 150 °C in the peak reduction temperature from 1130 to 980 °C was observed during the experimentation, however, the peak reduction efficiency was reduced from 81 to 63% when no additive was used. The gradual addition of C2H5OH up to a molar ratio of 2.0 further impairs the peak NOx reduction efficiency by reducing it to 50% but this is accompanied by a downward shift of 180 °C in the peak reduction temperature. Further exploration using C2H4(OH)2 suggested that a 50% reduction could be attained for all the temperatures higher than 940 °C. The use of C3H5(OH)3 as a secondary additive has a significant effect on the peak reduction efficiency that decreased to 40% the reductions were achievable at a much lower temperature of 800 °C showing a downward shift of 330 °C. 相似文献
24.
While various energy-producing technologies have been analyzed to assess the amount of energy returned per unit of energy
invested, this type of comprehensive and comparative approach has rarely been applied to other potentially limiting inputs
such as water, land, and time. We assess the connection between water and energy production and conduct a comparative analysis
for estimating the energy return on water invested (EROWI) for several renewable and non-renewable energy technologies using
various Life Cycle Analyses. Our results suggest that the most water-efficient, fossil-based technologies have an EROWI one
to two orders of magnitude greater than the most water-efficient biomass technologies, implying that the development of biomass
energy technologies in scale sufficient to be a significant source of energy may produce or exacerbate water shortages around
the globe and be limited by the availability of fresh water. 相似文献
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26.
本文使用了详细化学反应动力学机理计算模拟了混合有乙醇及典型自由基引导的甲烷预混火焰结构.该反应机理由Marinov研究组研究发表,包含有56个组分以及372个反应.本文的计算使用了CHEMKIN-3以及预混火焰代码,热力学及输运部分的计算基于Sandia国家实验室和Marinov研究室发布的数据库.火焰结构中主要产物的变化,关键中间产物和次要组分的计算结果显示加入乙醇和自由基都可以减少着火延迟.本文计算了三种不同条件下的火焰结构,分别为预混CH4/O2/N2火焰;预混甲烷/乙醇火焰;和加入引导自由基在甲烷/乙醇混合燃料中.此外还有含有自由基的甲烷火焰和加入乙醇的甲烷火焰比较. 相似文献
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28.
夏荣波 《环境监测管理与技术》2014,26(1):46-48
采用蒸馏水吸收空气中的乙醇和异丙醇,气相色谱法测定,该方法在3.14 mg/L ~15.8 mg/L 范围内线性良好,乙醇标准曲线的相关系数为0.9994,异丙醇标准曲线的相关系数为0.9996。测定低浓度标准溶液,得到乙醇和异丙醇的检出限分别为0.418 mg/L 和0.399 mg/L;采样体积为0.04 m3时,乙醇和异丙醇最低检出质量浓度均为0.05 mg/m3。乙醇和异丙醇标准溶液的回收率为95.4%~104%,RSD<5%。样品稳定性试验表明,采集的乙醇和异丙醇样品保存时间越长损失率越大,一般保存7 d为宜。 相似文献
29.
Yong-Zhong Wang Yan-Mei Wang Rong Chen Qiang Liao Xun Zhu 《International Journal of Green Energy》2015,12(10):1031-1036
In the present work, characteristics of ethanol production from a single particle composing of pretreated rice straw, cellulase, and β-glucosidase were invesitgated by simultaneous saccharification and fermentation (SSF). The experiment experienced a start-up stage for S. cerevisiae biofilm formation, which was operated at an initial pH value of 4.8 for yeast solution, culture temperature of 30°C, flow rate of 0.8 mL/min for yeast solution, and stably operating stage for ethanol production at a culture temperature of 30°C. Investigations found that the maximal ethanol yield of 9.7 mg/g and the biofilm thickness of 0.37 mm were obtained at 30 mL/min of carrier gas flow rate. Also, the optimal interval time of water supplement was 4 h for SSF. The results show that the appropriate gas flow rate and the interval time of water supplement can keep the high activities of biofilm and enzymes during SSF and result in a high ethanol yield. 相似文献
30.
Abdi Christia Arima Diah Setiowati Keikhosro Karimi Muhammad Nur Cahyanto Claes Niklasson 《International Journal of Green Energy》2016,13(6):566-572
Oil palm empty fruit bunch (OPEFB) is a potential raw material for production of lignocellulosic bioethanol. The OPEFB was pretreated with 8% sodium hydroxide (NaOH) solution at 100°C for 10 to 90 min. Enzymatic digestion was carried out using cellulase and β-glucosidase at 45°C for 24 h. It was then inoculated with Mucor indicus spores suspension and fermented under anaerobic conditions at 37°C for 96 h. Sodium hydroxide pretreatment effectively removed 51–57% of lignin in the OPEFB and also its hemicellulose (40–84%). The highest glucan digestibility (0.75 g/g theoretical glucose) was achieved in 40-min NaOH pretreatment. Fermentation by M. indicus resulted in 68.4% of the theoretical ethanol yield, while glycerol (16.2–83.2 mg/g), succinic acid (0–0.4 mg/g), and acetic acid (0–0.9 mg/g) were its by-products. According to these results, 11.75 million tons of dry OPEFB in Indonesia can be converted into 1.5 billion liters of ethanol per year. 相似文献