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排序方式: 共有595条查询结果,搜索用时 31 毫秒
31.
32.
Tomy GT Pleskach K Ismail N Whittle DM Helm PA Sverko E Zaruk D Marvin CH 《Environmental science & technology》2007,41(7):2249-2254
The extent of bioaccumulation of the syn- and anti-isomers of Dechlorane Plus (DP) is assessed in archived food web samples from Lake Winnipeg and Lake Ontario. Concentrations of the isomers were determined using purified analytical solutions of individual isomers as opposed to the technical mixture. The syn-isomer was consistently detected in all samples from both lakes; the anti-isomer was detected in all Lake Ontario samples, but only 45% of the samples from Lake Winnipeg. The pattern of bioaccumulation was different for the isomers in Lake Winnipeg. The anti-isomer was dominant in higher trophic level (TL) organisms like walleye [arithmetic mean +/- 1 x standard error: 730 +/- 120 pg/g, lipid weight (1w)] and goldeye (760 +/- 170 pg/g, Iw) while the syn-isomer dominated the lower TL organisms like zooplankton (550 +/- 40 pg/g, Iw) and mussels (430 +/- 140 pg/g, Iw). In Lake Ontario, the extent of bioaccumulation of the isomers and concentrations was greatest in the lower TL benthic organism, Diporeia (syn, 1307 +/- 554; and anti, 3108 +/- 898 pg/g Iw) and also high in zooplankton (syn, 719; and anti, 1332 pg/g Iw). This suggests that the isomers are bioavailable in sediment and that, despite their molecular size, diffusion from the water column into zooplankton can occur. Differences in the mean fractional abundance of the anti-isomer (mean fanti = mean concentration of the anti-isomer divided by sum of mean syn- and anti-concentrations) were pronounced in sediments between lakes (Lake Winnipeg mean fanti = 0.610, Lake Ontario mean fanti = 0.860) and the extent of enrichment (anti-) and depletion (syn-) of the isomers were more marked in Lake Winnipeg biota. There were also differences in the biomagnification potentials, as measured bythe trophic magnification factor (TMF), between the isomers in the Lake Winnipeg food web; no statistically significant TMFs for either isomer were found for the 相似文献
33.
Simon Rendel Ian Thompson Paul Gough Andrew Cherrill Joshua Pollard Ed Bennis 《Landscape Research》1997,22(2):225-235
Landscape Transformed
London, Academy Editions, 1996, 112 pp., no price given, ISBN 1-85490-452-3
Sculpting with the Environment: a natural dialogue
Baile Oakes (Ed.)
New York, Van Nostrand Reinhold, 1995, ISBN 0-442-01642-5, 252 pp., £45.00, hb.
After the Ruins: restoring the countryside of Northern France after the Great War
Hugh Clout
Exeter, University of Exeter Press, 1996, ISBN 0-85989-491-6,332 pp., £35.
Environmental Aesthetics: ideas, politics and planning
J. Douglas Porteous
London and New York, Routledge, 1996, ISBN 0-415-13769-1, 20 pp., £15.99.
Countryside Survey 1990 Main Report
C.J. Barr, R.G.H. Bunce, R.T. Clarke, R.M. Fuller, M.T. Furse, M.K. Gillespie, G.B. Groom, C.J. Hallam, M. Hornung, D.C. Howard & M.J. Ness
London, Department of the Environment, 1993, 174 pp., £12.00 (available from DoE Publications Sales Unit, Block 3, Spur 2, Government Buildings, Lime Grove, Eastcote, HA4 8SE)
World of Environmental Design, Volume 1: Urban Spaces I (Streets and Squares)
Francisco Asenio Cerver
Barcelona, Arco Editorial, 1995, 255 pp., US$75 (per volume) ISBN 84-8185-004-7 (complete work), ISBN 84-8185-005-5 (Volume 1)
'The Remains of Distant Times': archaeology and the National Trust
David Morgan Evans, Peter Salway & David Thackray (Eds)
Woodbridge, Suffolk, The Boydell Press, 1996, ISBN 0-85115-671-1, hb, 235 pp., £29.50
Apostle of Taste: Andrew Jackson Downing 1815-1852
D. Schuyler
Baltimore, fohns Hopkins University Press, 1996, ISBN 0-8018-5229-3, $35.95 相似文献
London, Academy Editions, 1996, 112 pp., no price given, ISBN 1-85490-452-3
Sculpting with the Environment: a natural dialogue
Baile Oakes (Ed.)
New York, Van Nostrand Reinhold, 1995, ISBN 0-442-01642-5, 252 pp., £45.00, hb.
After the Ruins: restoring the countryside of Northern France after the Great War
Hugh Clout
Exeter, University of Exeter Press, 1996, ISBN 0-85989-491-6,332 pp., £35.
Environmental Aesthetics: ideas, politics and planning
J. Douglas Porteous
London and New York, Routledge, 1996, ISBN 0-415-13769-1, 20 pp., £15.99.
Countryside Survey 1990 Main Report
C.J. Barr, R.G.H. Bunce, R.T. Clarke, R.M. Fuller, M.T. Furse, M.K. Gillespie, G.B. Groom, C.J. Hallam, M. Hornung, D.C. Howard & M.J. Ness
London, Department of the Environment, 1993, 174 pp., £12.00 (available from DoE Publications Sales Unit, Block 3, Spur 2, Government Buildings, Lime Grove, Eastcote, HA4 8SE)
World of Environmental Design, Volume 1: Urban Spaces I (Streets and Squares)
Francisco Asenio Cerver
Barcelona, Arco Editorial, 1995, 255 pp., US$75 (per volume) ISBN 84-8185-004-7 (complete work), ISBN 84-8185-005-5 (Volume 1)
'The Remains of Distant Times': archaeology and the National Trust
David Morgan Evans, Peter Salway & David Thackray (Eds)
Woodbridge, Suffolk, The Boydell Press, 1996, ISBN 0-85115-671-1, hb, 235 pp., £29.50
Apostle of Taste: Andrew Jackson Downing 1815-1852
D. Schuyler
Baltimore, fohns Hopkins University Press, 1996, ISBN 0-8018-5229-3, $35.95 相似文献
34.
Bibliometric maps have the potential to become useful tools for science policy issues. The complexity of the structures, however,
makes it often very difficult to interpret the results. In this study, we present a case study in which we use the bibliometric
mapping results to address a high level science policy issue of research efficiency. By revealing the results in an alternative
way, we increased the utility of bibliometric mapping within the science policy context. Moreover, by including additional
information to the entities in the landscape, we provide useful input for the research potential. 相似文献
35.
Gump Brooks B.; Reihman Jacki; Stewart Paul; Lonky Ed; Granger Douglas A.; Matthews Karen A. 《Canadian Metallurgical Quarterly》2009,28(5):614
Objective: The authors recently reported that blood lead (Pb) was a significant mediator for the positive association between socioeconomic status (SES) and peripheral vascular responses to acute stress in children (B. B. Gump et al., 2007). The present study considers the possibility that Pb may also mediate an association between SES and cortisol responses to acute stress. Design: Early childhood Pb exposure was tested as a mediator for cross-sectional associations between SES and cortisol responses. Main Outcome Measures: The primary outcome was cortisol responses to acute stress in 9.5-year-old children (N = 108). Results: Lower family income was associated with significantly greater cortisol levels following an acute stress task. A mediational analysis confirmed that Pb was a significant mediator for this association. Conclusion: These results reaffirm the importance of considering the chemical environment as well as social and psychological environment when evaluating psychophysiological effects of low SES. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Ed Mines 《Rocks & Minerals》2013,88(5):318-342
In 1875 Colorado was still a territory awaiting statehood, ulysses Grant was serving his second term as president, and Benjamin Disraeli was in his second term as prime minister of Creat Britain; parts of the South were still suffering under the reconstruction policies of the “Radical Republicans,” Georges Bizet's Carmen opened in Paris, and the city of London completed construction of its new sewerage system. Also in that year yet mother military buildup was taking place in Europe—Russia's standing army reached 3,360,000 men and Germany's 2,800,000; a period of unrest boiled over in the Balkans as Bosnia and Herzegovina rebelled against Turkish rule, and P. E. Lecoq discovered the new element gallium. The year 1875 saw the publication of Samuel Clemens's The Adventures of Tom Sawyer, while impressionist artist Claude Monet completed his painting Boating at Argenteuil—and John Fallon discovered gold and silver in the high mountains near where the town of Telluride would one day be located. 相似文献
37.
38.
V. A. PATTINSON BSc PhD D. P. BUTCHER BA Cert Ed PhD J. C. LABADZ BSc PhD 《Water and Environment Journal》1994,8(3):298-307
The problems of water-colour management in peatland catchments are discussed. Colour may be managed in three areas of the reservoir catchment system: on the catchment itself, in the channel/conduit system and within the reservoir. Whilst a number of workers have considered the management of catchment areas and some have evolved tributary turnout strategies, no previous research has considered the role of the reservoir in the amelioration or enhancement of water colour. The management of water colour at Thornton Moor catchment (near Bradford) is described. In this catchment a staged approach has been adopted, with colour being managed in an integrated manner at three stages along the catchment/conduit/reservoir system. 相似文献
39.
Muhammad Mustafa Hussain Ed Labelle Gabe Gebara Naim Moumen 《Microelectronic Engineering》2007,84(4):594-598
International Technology Roadmap for Semiconductors 2003 projected nano-imprint lithography has the potential of high throughput, sub-20 nm resolution, and low cost [S.Y. Chou, P.R. Krauss, P.J. Renstrom, Appl. Phys. Lett. 67 (1995) 3144; Science 272 (1996) 85, J.A. Rogers, C. Mirkin, Mater. Res. Bull. 26 (2001)]. For nano-imprint lithography, a template with 1X resolution is required. The existing industrial infrastructure for supporting deep ultra violet 4X photo masks by e-beam and/or a laser beam scanning writer does not offer pitch (center-to-center distance of an array of patterned lines) less than ∼60 nm [<http://public.itrs.net/2003ITRS>]. For nano-imprint lithography to be accepted across the industry, a reproducible simple fabrication process to make a high resolution, single emboss template is essential [L. Jay Guo, J. Phys. D: Appl. Phys. 37 (2004) R123-R141]. Here we show, a general fabrication method and fabricated nano-imprint templates with sub-15 nm template line width and 10 nm pitch length through out the entire 200 mm wafer, varying the deposition thickness of multiple alternate films, using atomic layer deposition. Although multilayer nano-imprint templates and their exciting use have been demonstrated, [W.J. Dauksher et al., J. Vac. Sci. Technol. B 22 (2004) 3306, B. Heidari, et al., The 49th international conference on electron, ion and photon beam technology and nanofabrication, Orlando, Florida, 2005, William M. Tong, et al., Proc. SPIE 5751 (2005) 46-55, N.A. Melosh, A. Boukai, F. Diana, B. Gerardot, A. Badolato, P.M. Petroff, J.R. Heath, Science 300 (2003) 112] such a small pitch was not shown and either complex lattice mismatch-based epitaxially grown films or unconventional etch chemistry was used. The bare necessity was a simple and economical fabrication process for a high throughput nano-imprint template. In that context, we have developed a template fabrication process using classical micro-fabrication techniques. Successful use of these techniques made the template fabrication process simple, economical, and expedient. Also a novel technique to provide flexible and accurate alignment for nanowire patterning has been described. In this technique, nanowire patterning is accomplished on the entire wafer with a single impression. Industry level batch-fabrication of our scheme illustrates its reproducibility and manufacturability. We anticipate, this simple, economical and time saving technique will help researchers and developers to perform their experiment on nano-scale feature patterned substrates easily and conveniently. 相似文献
40.
E. Deprettere P. Dewilde 《International Journal of Circuit Theory and Applications》1980,8(3):245-272
A generally applicable theory for multiport orthogonal digital filter synthesis is discussed, using a direct algebraic method. Standard (complex) degree 1 and irreducible (real) degree 2 chain scattering matrices are derived and the computability problem which normally occurs in such filters is discussed and solved for the general case. It is shown that any finite causal and lossless real multivariate system can be realized as a computationally compatible cascade of real degree 1 and degree 2 factors consisting of an orthogonal constant interconnecting part and a lossless dynamic portion. In order to increase the practical interest of the paper, realizations of these sections are explicitly given. The known scalar wave digital filter ‘adaptors’ emerge as a special case of the theory presented in this paper. The general results are of interest in multiport digital signal processing, in multivariate interpolation theory and in multichannel prediction and modelling theory and techniques. 相似文献