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排序方式: 共有608条查询结果,搜索用时 15 毫秒
1.
通过研究润滑油糠醛精制装置抽出液回收系统二、三效蒸发塔压控调整对装置能耗的影响发现,三效蒸发塔进行憋压操作对装置能耗降低是有利的,二效蒸发塔在憋压时极易降低醛气的蒸发量,并且对能耗的影响也不大,最终得出装置较优的操作参数,既解决了糠醛干燥塔液面受外界影响波动较大的问题也降低了装置能耗。 相似文献
2.
通过掺加不同含量糠醛抽出油、红油增塑剂与苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性剂,分析其对SBS改性沥青各性能指标的影响,判断影响SBS改性沥青性能的主要因素。结果表明:改性沥青中SBS改性剂含量是提高软化点、弹性恢复的主要因素;糠醛抽出油含量增大则可明显提高其延度指标,且改善SBS改性沥青的离析程度;红油增塑剂含量增大可大幅提高SBS改性沥青的延度指标,但高温性能下降且离析严重,短期老化后指标下降幅度高于同等含量抽出油老化后指标。因此可在SBS含量确定的情况下,通过掺加适当的糠醛抽出油以改善SBS改性沥青的性能。 相似文献
3.
Antoine Depoorter Carmen Kalalian Corinne Emmelin Chantal Lorentz Christian George 《Indoor air》2021,31(3):682-692
People spend approximately 80% of their time indoor, making the understanding of the indoor chemistry an important task for safety. The high surface-area-to-volume ratio characteristic of indoor environments leads the semi-volatile organic compounds (sVOCs) to deposit on the surfaces. Using a long path absorption photometer (LOPAP), this work investigates the formation of nitrous acid (HONO) through the photochemistry of adsorbed nitrate anions and its enhancement by the presence of furfural. Using a high-resolution proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS), this work also investigates the surface emissions of VOCs from irradiated films of furfural and a mix of furfural and nitrate anions. Among the emitted VOCs, 2(5H)-furanone/2-Butenedial was observed at high concentrations, leading to maleic anhydride formation after UV irradiation. Moreover, the addition of potassium nitrate to the film formed NOx and HONO concentrations up to 10 ppb, which scales to ca. 4 ppb for realistic indoor conditions. This work helps to understand the high levels of HONO and NOx measured indoors. 相似文献
4.
The influence of malt and wort processing on spirit character: the lost styles of Scotch malt whisky
George N. Bathgate 《Journal of the Institute of Brewing》2019,125(2):200-213
Over the last 50 years there has been considerable analytical research on the malt parameters which govern the flavour and aroma, i.e. the ‘character’, of Scotch malt whisky. This has led to a standard format, the Flavour Wheel, to describe the attributes of any malt spirit and to relate them to a common group of malt parameters. What has not been well documented in the same period are the changes in malt processing technology which have led to a gradual but significant change in the concentrations of reference compounds used in the Flavour Wheel relating to sulphury, nutty/burnt/smoky, peaty and fruity/estery characters. This review covers the most significant of these changes, which have become common practice across the industry, and specifically demonstrates how different malting barley varieties, malt kilning and peating, wort recovery, yeast management, and wash still heating have all contributed to the loss of some styles of malt whisky. © 2019 The Institute of Brewing & Distilling 相似文献
5.
Yanyan Cheng Guanghui Sui Huan Liu Xiaofeng Wang Xiaomin Yang Zichen Wang 《应用聚合物科学杂志》2019,136(4):46995
Highly phenol substituted bio-oil–phenol–formaldehyde (BPF) adhesives were prepared via the phenolization-copolymerization method, in which furfural was used as a novel crosslinking agent to improve the bonding performance. The effects of bio-oil percentage, furfural content, curing temperature, and pressure on the performance of BPF adhesives have been studied in detail. A BPF adhesive with 75% bio-oil percentage and 15% furfural loading (named 75BPF_15) was synthesized, which was cured at 180 °C and 4 MPa. Compared to the conventional phenol–formaldehyde adhesive, the wet tensile strength of 75BPF_15 adhesive reached 2.84 MPa, which was significantly higher than the 1.54 MPa of PF. A possible mechanism of BPF adhesives crosslinked with furfural is proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46995. 相似文献
6.
Safa Karaman Omer Said Toker Mustafa Çam Mahmut Doğan Ahmed Kayacier 《Drying Technology》2014,32(3):258-267
In this study, the effects of three different drying methods (freeze drying, oven drying, and vacuum oven drying) on bioactive (total phenolics, total flavonoids, condensed tannin and total hydrolyzable tannin contents, antiradical activity, and antidiabetic activity) and some physicochemical (dry matter, ash, water activity (a w ), color, protein, hydroxymethylfurfural, glucose and fructose content) properties of persimmon fruit were investigated. Simplex lattice mixture design methodology was applied to determine the best solvent mixture for the extraction of phenolics from the samples. It was found that the mixture of acetone:water at the ratio of 50:50 % (v/v) was the best solvent mixture for the extraction. The persimmon powder sample obtained from freeze drying showed significantly (p <0.05) higher bioactivity values than oven- and vacuum-oven-dried samples. Antiradical activity changed significantly depending on the drying method employed and it was superior in freeze-dried samples than that of the other drying methods. 相似文献
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