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281.
Malcolm Glennie Holmes 《Journal of the Institute of Brewing》1995,101(1):29-32
Examination of the relationships between extract and viscogram data of malts suggested the measurement of Time to Peak as a cultivar-independent measure of quality potential. This was tested against a large number of samples from the routine assessment programme. Both barleys and malts were examined. Some comparisons with the Falling Number Apparatus are reported. Prediction of malting potential from the differences between viscograms of barleys with and without added enzyme was also assessed. No measurement from the viscogram of barley was sufficiently accurate for predicting malting potential of a population of crossbreds from a breeding programme. 相似文献
282.
Fernandes A Dicks P Mortimer D Gem M Smith F Driffield M White S Rose M 《Molecular nutrition & food research》2008,52(2):238-249
The most commonly consumed shellfish species produced in Scotland - mussels, oysters and scallops - were investigated for the occurrence of a range of brominated and chlorinated contaminants in order to establish current levels and estimate human dietary exposure. Flesh from individual sub-samples was representatively pooled and 35 composites were analysed for brominated and chlorinated dioxins (PBDD/Fs, PCDD/Fs), brominated and chlorinated biphenyls (PBBs, PCBs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA). The analytical methodology used (13)C(12) labelled surrogates of the target compounds, with GC coupled to (usually) high resolution MS, and LC-MS/MS for HBCD and TBBPA analysis. Positive identifications were made in the majority of samples for most analytes with the exception of TBBPA and most PBDD congeners measured. None of the levels detected for PCDD/F and PCB were above the maximum permitted levels specified in European Union regulations. The levels of brominated furans predominated over brominated dioxins, reflecting the environmental distribution and source emission profiles of these contaminants, and relatively high levels of the tri-brominated congeners were observed. Levels of the flame retardant chemicals reflected current and legacy use, with appreciable concentrations of PBDEs and HBCDs (predominantly alpha-HBCD) but far lower levels of PBBs. TBBPA was not detected in any of the species. In general, mussels and oysters displayed relatively higher levels of contamination than scallops, although the gonad tissue of the latter showed significant levels of brominated dioxins. The estimated adult dietary intakes of PCDD/Fs and PCBs arising from the consumption of a typical portion of these foods in combination with an otherwise average UK diet were in the range 0.5-0.6 pg World Health Organisation (WHO)-toxic equivalent (TEQ)(2005)/kg bodyweight per day. These estimated dietary intakes are well within the Tolerable Daily Intake for dioxins and dioxin-like PCBs of 2 pg WHO-TEQ(2005)/kg bodyweight/day endorsed by the independent expert Committee on Toxicology of Chemicals in Food, Consumer Products and the Environment. The corresponding intakes for sumPBDEs and sumHBCDs were 5.6-6.1 and 5.9-7.9 ng/kg bodyweight/day respectively. 相似文献
283.
During the past decade, the invasive Phragmites australis (common reed) has established itself along beaches of the Great Lakes, causing detrimental impacts to both the natural ecological integrity of the shoreline and the recreational value of beaches. The herbicide Roundup®, containing the active ingredient glyphosate, was applied to Phragmites along a beach on the southern shore of Georgian Bay, Canada, to eradicate the Phragmites which was destroying the natural beach ecosystem. Groundwater and lake water were tested to determine if glyphosate enters the groundwater and lake at the beach and how long glyphosate will persist. Two days after application, the geometric mean concentration of glyphosate in the groundwater below the Phragmites was 0.060 μg/L with a maximum of 12.50 μg/L. Concentrations rapidly declined over the next two to three weeks to below minimum detection limits (< 0.020 μg/L). Glyphosate was also detected in the nearshore lake water with concentrations peaking at a geometric mean of 0.14 μg/L one week after application, and declining to 0.039 μg/L four weeks after application. Concentrations of glyphosate never exceeded the Canadian water quality guideline for the protection of aquatic life (65 μg/L) in either the groundwater or lake water. An approximate half-life for the dissipation of glyphosate by degradation and dilution/flushing as groundwater flows toward the lake, assuming a first order kinetic reaction, yielded a half-life of 3.5 during the 4 weeks after the herbicide was applied. The application of Roundup® resulted in an 90% reduction in the size of the stand of Phragmites. 相似文献
284.
Fuel cells aboard hybrid electric vehicles (HEVs) are often hybridized with an energy storage system (ESS). Batteries and ultracapacitors are the most common technologies used in ESSs aboard HEVs. High-speed flywheels are an emerging technology with traits that have the potential to make them competitive with more established battery and ultracapacitor technologies in certain vehicular applications. This study compares high-speed flywheels, ultracapacitors, and batteries functioning as the ESS in a fuel cell based HEV on the bases of cost and fuel economy. In this study, computer models were built to simulate the powertrain of a fuel cell based HEV where high-speed flywheels, batteries, and ultracapacitors of a range of sizes were used as the ESS. A simulated vehicle with a powertrain using each of these technologies was run over two different drive cycles in order to see how the different ESSs performed under different driving patterns. The results showed that when cost and fuel economy were both considered, high-speed flywheels were competitive with batteries and ultracapacitors. 相似文献
285.
Anaerobic methane oxidation and aerobic methane production in an east African great lake (Lake Kivu) 总被引:1,自引:0,他引:1
Fleur A.E. Roland Cédric Morana François Darchambeau Sean A. Crowe Bo Thamdrup Jean-Pierre Descy Alberto V. Borges 《Journal of Great Lakes research》2018,44(6):1183-1193
We investigated CH4 oxidation in the water column of Lake Kivu, a deep meromictic tropical lake with CH4-rich anoxic deep waters. Depth profiles of dissolved gases (CH4 and N2O) and a diversity of potential electron acceptors for anaerobic CH4 oxidation (NO3?, SO42?, Fe and Mn oxides) were determined during six field campaigns between June 2011 and August 2014. Denitrification measurements based on stable isotope labelling experiments were performed twice. In addition, we quantified aerobic and anaerobic CH4 oxidation, NO3? and SO42? consumption rates, with and without the presence of an inhibitor of SO42?-reducing bacteria activity. Aerobic CH4 production was also measured in parallel incubations with the addition of an inhibitor of aerobic CH4 oxidation. The maximum aerobic and anaerobic CH4 oxidation rates were estimated to be 27?±?2 and 16?±?8?μmol/L/d, respectively. We observed a difference in the relative importance of aerobic and anaerobic CH4 oxidation during the rainy and the dry season, with a greater role for aerobic oxidation during the dry season. Lower anaerobic CH4 oxidation rates were measured in presence of molybdate in half of the measurements, suggesting the occurrence of linkage between SO42? reduction and anaerobic CH4 oxidation. NO3? consumption and dissolved Mn production rates were never high enough to sustain the measured anaerobic CH4 oxidation, reinforcing the idea of a coupling between SO42? reduction and CH4 oxidation in the anoxic waters of Lake Kivu. Finally, significant rates (up to 0.37?μmol/L/d) of pelagic CH4 production were also measured in oxygenated waters. 相似文献
286.
Derek G. Land Malcolm G. Gee Jennifer M. Gee Christopher A. Spinks 《Journal of the science of food and agriculture》1975,26(10):1585-1591
Two unknown components in extracts of broiler house litter were identified as 2,4,6-trichloroanisole and 2,4,6-trichlorophenol; the latter compound was also found in extracts of fresh wood shavings. Experiments with pure cultures of fungi isolated from the litter demonstrated that these microorganisms were capable of methylating 2,4,6-trichlorophenol to the chloroanisole. A musty taint in broiler chickens was shown to be due to the presence of 2,4,6-trichloroanisole. 相似文献
287.
R. B. Sayce A. D. Bradshaw Malcolm MacEwen Brian Goodey Joy Tivy Ian Brotherton 《Landscape Research》1982,7(2):30-32
FARMED LANDSCAPES: THE WAY AHEAD by the Agrolandscapes Working Party. RIBA Bookshops, 1981. £1 (paperback).
ECOLOGY AND PLANNING by P.H.Selman, George Godwin, London, 1981.
THE MAKING OF NEIGHBOURHOOD OPEN SPACES: COMMUNITY DESIGN, DEVELOPMENT AND MANAGEMENT by Mark Francis, Lisa Cashdan & Lynn Paxson. Center for Human Environments, City University of New York, 1981.
WATER PLANNING IN BRITAIN by Dennis J. Parker and Edmund C. Penning-Rowsell. Resources Management Series Volume 1, Editors Richard Munton and Judith Rees. George Allen and Unwin, London, 1980.
COUNTRYSIDE PLANNING YEARBOOK edited by Andrew Gilg. Volume 3, 228 pages. Geo Books, Norwich, 1982. 相似文献
ECOLOGY AND PLANNING by P.H.Selman, George Godwin, London, 1981.
THE MAKING OF NEIGHBOURHOOD OPEN SPACES: COMMUNITY DESIGN, DEVELOPMENT AND MANAGEMENT by Mark Francis, Lisa Cashdan & Lynn Paxson. Center for Human Environments, City University of New York, 1981.
WATER PLANNING IN BRITAIN by Dennis J. Parker and Edmund C. Penning-Rowsell. Resources Management Series Volume 1, Editors Richard Munton and Judith Rees. George Allen and Unwin, London, 1980.
COUNTRYSIDE PLANNING YEARBOOK edited by Andrew Gilg. Volume 3, 228 pages. Geo Books, Norwich, 1982. 相似文献
288.
M W Neathery C T Crowe G F Hartnell J J Veenhuizen D M Blackmon M J Azain 《Journal of dairy science》1991,74(12):4314-4319
The metabolism of Zn and tissue mineral concentrations were studied after a single oral 65Zn dose in 10 6-wk-old Holstein calves injected subcutaneously daily with 0 (control) or 10 mg of sometribove (recombinant methionyl bST) for 6 wk. Zinc-65 absorption was not significantly affected by bST; its concentration in the semitendinosus muscle was reduced by 32% in the bST calves, but concentrations in liver, pancreas, spleen, kidney, heart, small intestine, testicle, and rib were not different from controls. Manganese content was reduced by 27% in liver, 60% in kidney, 99% in spleen, 92% in testicles, and 33% in rib. Iron content of pancreas, spleen, and testicle and Zn content of rib were increased in the bST calves. The data indicate that Zn metabolism was not affected adversely by bST. Manganese content of several tissues was significantly reduced in the bST calves; however, no clinical signs of an Mn deficiency were evident. 相似文献
289.
Nanthi S Bolan J Keith Syers Malcolm E Sumner 《Journal of the science of food and agriculture》1991,57(4):527-541
The dissolution of six sources of gypsum in water and 0.01 M CaCl2 was examined in the presence and absence of soil. The gypsum samples included: analytical grade (AR), three sources of flue-gas desulphurisation (FGD) gypsum, phosphogypsum (PG), and mined gypsum (MG). Dissolution in aqueous solutions was monitored by measuring the concentration of calcium (Ca2+) and sulphate (SO) ions. In soils which adsorb small amounts of SO?24, dissolution was estimated from the increase in the concentration of Ca2+ and SO in gypsum-treated soil over the control soil. However, in soils which adsorb significant amounts of SO, measurement of solution SO concentration underestimates the extent of dissolution. Gypsum dissolution was larger in water (15.20 mmol litre?1) than in 0.01 M CaCl2 (11.12 mmol litre?1), and this was attributed to the Ca2+ common-ion effect. The rate of dissolution decreased in the order: AR > FGD > PG > MG. Dissolution was 2 to 10 times faster for powdered (< 500 .m) gypsum than for the discs obtained by pelletising. The differences in the rate of dissolution between the gypsum sources and between powder and disc samples were related to both surface area and the presence of CaCO3, impurity. The rate of dissolution was 3 to 8 times faster in the presence than in the absence of soil. Whereas the dissolution of gypsum in the presence of soil followed first order reaction kinetics, it followed second order kinetics in the absence of soil. This difference in reaction kinetics resulted from the continuous removal of Ca2+ and SO by the soil. 相似文献
290.
The signals at g≈2 in the e.p.r. spectra of Victorian brown coals are attributed to organic free radicals. Mathematical lineshape analysis and variation of linewidth with frequency suggested that the observed signals at low power levels are mainly homogeneously broadened. Power saturation experiments, however, resolved the signals to show the presence of from one to three resonances due to different free radical types. 相似文献