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61.
La Carbona S Viitasalo-Frösen S Masson D Sassi J Pineau S Lehtiniemi M Corroler D 《The Science of the total environment》2010,409(2):247-255
Ship's ballast waters transport large numbers of organisms which may become invasive in coastal regions. One option to address this problem is the use of biocides as ballast water treatment (BWT). Efficacy and environmental acceptability of three commercial active substances (the BWT biocides Peraclean® Ocean and Seakleen®, and alkylamine-based biocide Mexel® 432/336) were tested against three bacteria species, two vegetative microalgae and one zooplanktonic larva, in 10 and 30 Practical Salinity Unit (PSU) waters. In both salinities, PeraClean® Ocean was the most effective biocide against bacteria causing > 90% mortality at 20 mg/l, compared with 50 mg/l for Mexel® 432/336 and > 500 mg/l for Seakleen®. Regarding zooplankton, Seakleen® was the most effective chemical causing 90% mortality in 24 h at concentrations < 6 mg/l (LC9024 h) in both salinities, compared with 23 and 26 mg/l for Mexel® 432/336 and 370 and 480 mg/l for PeraClean® Ocean in 10 and 30 PSU, respectively. Similar pattern of efficacy was obtained for microalgae in 30 PSU: effective concentrations inducing 50% growth inhibition in 4 days were ≤ 1.6 mg/l for Seakleen®, ≤ 10.1 mg/l for Mexel® 432/336 and ≤ 30.9 mg/l for PeraClean® Ocean. Our work highlighted that treated waters displayed residual toxicity after 24 h still inducing mortality depending on the organism and biocide. However Mexel® 432/336 is the only biocide which had no impact on oyster larvae development at effective concentration. Altogether our data showed that Mexel® 432/336 was the only biocide displaying a broad spectrum efficacy in concentrations < 50 mg/l and not toxic for oyster larvae development at this concentration. However residual toxicity of treated waters for any organism should be taken into account in BWT systems utilising biocides. 相似文献
62.
The influence of air humidification in aircraft, on perception of cabin air quality among airline crew (N = 71) was investigated. In-flight investigations were performed in the forward part and in the aft part on eight intercontinental flights with one Boeing 767 individually, equipped with an evaporation humidifier combined with a dehumidifying unit, to reduce accumulation of condensed water in the wall construction. Four flights had the air humidification active when going out, and turned off on the return flight. The four others had the inverse humidification sequence. The sequences were randomized, and double blind. Air humidification increased relative air humidity (RH) by 10% in forward part, and by 3% in aft part of the cabin and in the cockpit. When the humidification device was active, the cabin air was perceived as being less dry (P = 0.008), and fresher (P = 0.002). The mean concentration of viable bacteria (77-108 cfu/m(3)), viable molds (74-84 cfu/m(3)), and respirable particles (1-8 microg/m3) was low, both during humidified and non-humidified flights. On flights with air humidification, there were less particles in the forward part of the aircraft (P = 0.01). In conclusion, RH can be slightly increased by using ceramic evaporation humidifier, without any measurable increase of microorganisms in cabin air. The cabin air quality was perceived as being better with air humidification. PRACTICAL IMPLICATION: Relative air humidity is low (10-20%) during intercontinental flights, and can be increased by using ceramic evaporation humidifier, without any measurable increase of microorganism in cabin air. Air humidification could increase the sensation of better cabin air quality. 相似文献
63.
Removal of sulphate and toxic elements from the leachate of a field landfill lysimeter (112m(3)), containing municipal solid waste incineration (MSWI) bottom ash, was studied. The leachate was treated in two parallel laboratory upflow anaerobic sludge blanket (UASB) reactors without and with ethanol as additional carbon source. With ethanol more than 65% of sulphate was removed, while without ethanol removal was negligible. The treatment removed Ba, Ca, Cu, Mn, Mo, Ni, Pb, Tl, Sb, Se, Sr, and Zn of the studied 35 trace and other elements. The sequential extraction of the reactor sludge at the end of runs confirmed that with a few exceptions (Ba, Ca, and Cu) the main mechanism by which the elements were removed was precipitation as sulphides. 相似文献
64.
Jukka K. Kaitaranta 《Journal of the science of food and agriculture》1980,31(12):1303-1308
The total lipids of whitefish flesh and roe averaged 3.0 and 9.8% fresh weight, respectively. Although neutral lipids dominated in both tissues the polar lipid content of fresh roe was unexceptionally high (2.5%). The fatty acid patterns of the total lipids from flesh and roe and of neutral lipids were similar to each other. Polyenoic acids constituted about half of the total fatty acids and monoenoic and saturated components existed in equal amounts. The calculated iodine values for the total lipids from flesh and roe indicated a slightly higher degree of unsaturation for roe fatty acids. The polar lipids were enriched in polyenoic and saturated fatty acids. Similarities in the composition and content of fatty acids from flesh and roe suggest that storage problems, apparent as a rancidity of roe products, may result from the high content of polar lipids readily hydrolysed during storage. 相似文献
65.
Variation in α‐acetolactate production within the hybrid lager yeast group Saccharomyces pastorianus and affirmation of the central role of the ILV6 gene 下载免费PDF全文
66.
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
67.
Isosaari P Kankaanpää H Mattila J Kiviranta H Verta M Salo S Vartiainen T 《Environmental science & technology》2002,36(12):2560-2565
Dated sediment cores and surface sediments were analyzed from the Gulf of Finland, a part of the Baltic Sea, to study the sources, levels, distribution, and total amounts of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs). The gulf was found to be severely polluted, with PCDD/F sum concentrations as high as 101000 ng/kg and 479 ng/kg WHO-TEQ in dry weight. The source of pollution was the former manufacturing and use of a chlorophenol based wood preservative along the Kymijoki River. It was estimated thatthe impacted sedimentary area stretched a distance of 75 km away out from the coast and that the PCDD/F sum load attributed to the wood preservative source was 1770 kg of PCDD/Fs or 12.4 (+/-2.8) kg WHO-TEQ. The surface sediments contained 24-66% of the maximum concentrations present in the 1960-1970s, showing that the river still acts as a significant PCDD/F source and may contribute to the high levels in fish. Moreover, the reduced PCDD/F and PCB concentrations were partly due to the dilution by increased dry matter deposition. PCBs were uniformly distributed over the gulf, and the PCB load in the polluted area was 2020 kg or 0.14 kg WHO-TEG. 相似文献
68.
Tommy Munk Stefania Baldursdottir Sami Hietala Thomas Rades Markus Nuopponen Katriina Kalliomäki Heikki Tenhu Jukka Rantanen Clare J. Strachan 《Polymer》2013
The use of vibrational spectroscopy to investigate complex structural changes in polymers yields chemically rich data, but interpretation can be challenging and subtle but meaningful spectral changes may be missed through visual inspection alone. Multivariate analysis is an efficient approach to gain an oversight of small but systematic spectral differences anywhere within the spectra, providing further insight into structural changes and associated transformation mechanisms. In this study, the novel analytical approach of infrared spectroscopy combined with principal component analysis and Gaussian peak fitting was used to investigate the structural changes in aqueous solutions of a polymer, using poly(N-isopropyl acrylamide) (PNIPAM) in the atactic form and with controlled tacticity as a model system. Subtle spectral changes associated with the dehydration and phase separation upon heating included peak shifts, an area ratio change of the amide I band to the amide II band and formation of a new peak in the amide I band were efficiently detected. Dehydration and phase separation of PNIPAM occurred in two temperature ranges, one for the atactic and one for isotactic rich part, both involving a complex re-organization of the hydrogen bonds and change of the hydration layer. The changes agreed with existing results from other techniques, and new insights were gained into the effect of controlled tacticity on phase transformation behaviour. The study demonstrates that infrared spectroscopy combined with the multivariate analytical method principal component analysis and Gaussian peak fitting is an efficient approach to probing structural change in polymers during heating. The simplicity of the presented approach could find excellent use in analysing and understanding the molecular environment of a range of stimuli-responsive polymers, for instance block or grafted types of polymers, as well as those with controlled tacticity. 相似文献
69.
Lars-Erik Lindgren 《热应力杂志》2013,36(4):305-334
Welding simulation has advanced from the analysis of laboratory setups to real engineering applications during the last three decades. This development is outlined and the directions for future research are summarized in this review, which consists of three parts. This parts focuses on computational strategies and how they are integrated with other methods to facilitate the use of simulations in engineering. These developments have lead to the increased application of welding simulations in industry. 相似文献
70.
Therese Lindgren 《Journal of Housing and the Built Environment》2011,26(1):17-32
This paper is about what people conceive as just principles for the distribution of open space maintenance. Housing staff
and residents’ conceptions of just distribution of open space maintenance were studied in rental housing areas with large
green open spaces in Sweden. Qualitative interviews with nine housing staff members and 27 tenants in three multi-family housing
areas owned and managed by different municipal housing companies revealed widely varying conceptions. These could be partly
classified into three basic principles: equal outcome, same inputs and less inputs (when decline is high). The conceptions
varied among interviewees with different roles in providing upkeep, suggesting that they partly depended on the individual’s
insight into the services. These personal conceptions of justice influence how people experience service distribution in a
neighbourhood and pose a challenge for actors dealing with strategic decisions on open space maintenance. 相似文献