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51.
Woei L. Saw Graham J. Nathan Peter J. Ashman Zeyad T. Alwahabi Mikko Hupa 《Combustion and Flame》2010,157(4):769-777
Simultaneous measurement of the concentration of released atomic sodium, swelling, surface and internal temperature of a burning black liquor droplet under a fuel lean and rich condition has been demonstrated. Two-dimensional two-colour optical pyrometry was employed to determine the distribution of surface temperature and swelling of a burning black liquor droplet while planar laser-induced fluorescence (PLIF) was used to assess the temporal release of atomic sodium. The key findings of these studies are: (i) the concentration of atomic sodium released during the drying and devolatilisation stages was found to be correlated with the external surface area; and (ii) the insignificant presence of atomic sodium during the char consumption stage shows that sodium release is suppressed by the lower temperature and by the high CO2 content in and around the particle. 相似文献
52.
This paper illustrates the needs and challenges for the management of distributed manufacturing in a multi-company supply chain and processes these further as features of new IT systems. Requirements are collected from manufacturing companies and combined with insights from literature in the field of current ERP/MES system drawbacks, advantages, needs and challenges. The findings show that the needs and challenges in data integration inside SME networks are closely related to the limitations of current supply chain solutions. Current ERP-solutions lack extended enterprise support and a shared cloud-based approach. On the other hand, current MES solutions can operate the manufacturing process, but not for distributed manufacturing. As an answer to the requirements, we made a proposal for the core of architecture for next generation of MES solution in this position paper. Moreover, a pilot software tool has been developed to support the needs related to real time, cloud-based, light weight operation. 相似文献
53.
54.
Sulfur has for long been known as a problematic element for the quality of iron, but along with its accumulation it also causes physical problems in the blast furnace, so it is of central importance to safeguard its removal from the process. Sulfur‐related problems in the blast furnace were studied by applying a balance equation for the element at three industrial blast furnaces, tracking errors in the in‐ and outflows and estimating changes in the amount of accumulated sulfur. A hypothesis on the behaviour of sulfur in the process was proposed and supporting evidence of it was found through an analysis of dynamic phenomena in the hearth of one of the furnaces. 相似文献
55.
Identification of milk fat triacylglycerols was accomplished by capillary supercritical fluid chromatography (SFC) combined
with atmospheric pressure chemical ionization mass spectrometry [(APCI)MS]. Supercritical carbon dioxide was the carrier fluid
in SFC. Ionization was achieved by introducing vapor of ammonia in methanol into the ionization chamber, which resulted in
the formation of abundant [M+18]+ and [M-RCOO]+ ions of triacylglycerols. These ions defined both the molecular weight and the fatty acid constituents of a triacylglycerol,
respectively. SFC on a nonpolar stationary phase provided an efficient separation of triacylglycerols according to the combined
number of carbon atoms in the acyl chains of a molecule. In addition to the identification of the major chromatographic peaks
representing molecules with 26–54 acyl carbons, minor peaks representing triacylglycerols with an odd number of acyl carbons
were separated and identified. Furthermore, compositional information on partially separated isobaric triacylglycerols, which
differed substantially in the chain length of the fatty acyl residues, was achieved within some of the peaks. A new finding
of the present study was the formation of abundant [M+18]+ ions of saturated triacylglycerols in addition to diagnostic fragment ions, being of primary importance in structure elucidation.
This extends the applicability of capillary SFC-(APCI)MS in the analysis of both saturated and unsaturated triacylglycerols. 相似文献
56.
57.
Pivi Laakso 《European Journal of Lipid Science and Technology》2005,107(6):402-410
Two methods suitable for routine phytostanol/phytosterol analysis of various sterol‐enriched food matrices and phytostanyl/phytosteryl fatty acid ester ingredients are introduced. A method based on hot saponification of a sample with ethanolic potassium hydroxide in the presence of an internal standard (5β‐cholestan‐3α‐ol) is adequate for most matrices, such as spread, milk and yoghurt. Some matrices, like pasta, require acid hydrolysis in order to release matrix‐incorporated bound sterols or sterols from steryl glycosides before the saponification step. After saponification, the unsaponifiable material containing phytostanols and phytosterols is extracted into an organic solvent (e.g. heptane), followed by evaporation of the solvent to dryness. Sterols are separated as their trimethylsilyl ether derivatives with a gas‐liquid chromatograph (GC), on a column coated with 5% phenyl/95% dimethylpolysiloxane, and detected with a flame ionization detector. The GC conditions applied provide efficient separation of the most abundant phytostanols/phytosterols in 15 min, a wide linear range of stanols/sterols without the need of defining sterol response factors. The methods are repeatable and accurate, as shown with standard addition trials. These methods were applied to determine phytostanol/phytosterol contents of several sterol‐enriched functional food products, and the analyzed amounts were in good accordance with the information provided on the packaging labels. 相似文献
58.
Samuli Korkiakoski Mikko Haavisto Mohammad Rostami Barouei Olli Saarela 《Polymer Composites》2016,37(9):2692-2704
In this study, experimental test equipment developed in‐house was used to study the compaction behavior of stitched quasi‐unidirectional (UD) non‐crimp fabrics (NCF) during the pre‐filling, filling, and post‐filling stages of the vacuum infusion (VI) process. The effects of the stitch pattern, stitch tension, and fiber sizing of reinforcements, as well as the effect of nesting of fiber bundles in neighboring layers, were studied. Moreover, the effects of cyclic compaction, resin viscosity, and different post‐filling strategies were studied. The developed experimental test equipment provided an applicable measuring method for characterizing the compaction behavior of both the dry and resin‐impregnated reinforcements. The effects of the stitching parameters and fiber nesting of reinforcements were found. The stitch pattern and post‐filling strategies were noted to have an effect on the preform and laminate thickness. POLYM. COMPOS., 37:2692–2704, 2016. © 2015 Society of Plastics Engineers 相似文献
59.
Jukka Ekberg Brian Gibson Jussi J. Joensuu Kristoffer Krogerus Frederico Magalhães Atte Mikkelson Tuulikki Seppänen‐Laakso Arvi Wilpola 《Journal of the Institute of Brewing》2015,121(4):464-473
Sahti, a strong, unhopped farmhouse beer flavoured with juniper, is still actively brewed in rural areas in Finland. Presented here is the first comprehensive analysis of the physical and chemical properties of this unique beer style. Twelve sahti samples from the southwest of Finland were analysed and, while properties varied, the beers generally had high levels of alcohol (mean = 7.9% ABV) and high residual extract (mean = 9.5°P). Foam stability was negligible, as is typical for the style, and glycerol concentrations at 3.1 – 4.7 g L?1 were higher than in reference beers (commercial lager, wheat beer and porter). These features may be attributed to the very high gravity conditions employed in brewing sahti beers. Bitterness levels were relatively low (3–13 IBU) owing to the absence or moderate use of hops. All samples contained detectable levels of the clove‐like compound 4‐vinylguaiacol owing to the use of baker's rather than brewer's yeast for brewing. Concentrations of higher alcohols and esters were high, with many individual aroma compounds being above the normal flavour thresholds. Results have highlighted the uniqueness of this style of beer in comparison to commercially available beers and have contributed to our understanding of the reasons for the particular sensorial properties of this traditional beer style. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
60.
Vamsi Krishna Palukuru Jani Peräntie Mikko Komulainen Timo Tick Heli Jantunen 《Journal of the European Ceramic Society》2010,30(2):389-394
A tunable microwave phase shifter composed of a low-sintering-temperature, screen-printable barium strontium titanate (BST) film and silver metallization was fabricated on an alumina substrate and co-fired at 900 °C for 3 h. The dielectric properties of the films were characterized in a frequency range of 0.8–8 GHz using scattering parameter measurements and a quasi-static coplanar waveguide transmission line model. The temperature dependency of the films was measured through capacitance measurements in a frequency range of 0.5–2.5 GHz. The figure of merit (phase shift/dB of insertion loss) of the phase shifter was found to be 14.6 at 3 GHz with an applied bias field strength of 2.5 V/μm. The performance of the phase shifter is briefly discussed and compared with other phase shifters fabricated by direct screen-printing of BST films. 相似文献