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101.
Lavin KS Hageman KJ Marx SK Dillingham PW Kamber BS 《Environmental science & technology》2012,46(1):268-276
An approach using trace elements in particulate matter (PM) to identify the geographic sources of atmospherically transported semivolatile organic contaminants (SOCs) was investigated. Daily samples of PM and SOCs were collected with high-volume air samplers from 16 January to 16 February 2009 at Temple Basin, a remote alpine site in New Zealand's Southern Alps. The most commonly detected pesticides were dieldrin, trans-chlordane, endosulfan I, and chlorpyrifos. Polycyclic aromatic hydrocarbons and polychlorinated biphenyls were also detected. For each sampling day, the relative contribution of PM from regional New Zealand versus long-range Australian sources was determined using trace element profiles and a binary mixing model. The PM approach indicated that endosulfan I, indeno[1,2,3-c,d]pyrene, and benzo[g,h,i]perylene found at Temple Basin were largely of Australian origin. Local wind observations indicated that the chlorpyrifos found at Temple Basin primarily came from the Canterbury Plains in New Zealand. 相似文献
102.
F. Marx Eloisa Helena A. Andrade José Guilherme Maia 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,206(5):364-366
is a shrub native to the upper Orinoco region of the Amazon basin, previously cultivated by Indians throughout the Amazon
basin because of its edible fruits, which are rarely used nowadays. Analyses of its main components, i. e. carbohydrates,
minerals and trace elements, organic acids, fatty acids, free amino acids, biogenic amines and volatile compounds, are presented.
Received: 6 November 1997 相似文献
103.
104.
Feldheim W. Kiermeier F. Belitz H. -D. Thier H. -P. Diehl J. F. Fischer A. Marx F. Dettweiler G. Frommberger R. Krause E. W. Wachtendonk D. v. Bauer U. Vogelgesang J. Ledl F. Döppner Th. Schleifer G. 《European Food Research and Technology》1990,191(3):217-223
European Food Research and Technology - 相似文献
105.
106.
107.
Multi‐storey car park “centre hospitalier de Luxembourg“: Composite decking with fibre reinforced concrete. A multi‐storey car park was built for the “centre hospitalier de Luxembourg” in 2006 within a construction time of only eight months. It is the first application of a composite decking Cofraplus 60 with fibre reinforced concrete. The time for installing the rebars was extremely reduced. The slabs of the 4 storey building of an area of 125 m × 43,6 m have no joints. The car park offers 643 parking spaces and a helicopter pad on the roof. 相似文献
108.
Brian D. Marx 《技术计量学》2013,55(4):374-381
I extend the concept of partial least squares (PLS) into the framework of generalized linear models. A spectroscopy example in a logistic regression framework illustrates the developments. These models form a sequence of rank 1 approximations useful for predicting the response variable when the explanatory information is severely ill-conditioned. Iteratively reweighted PLS algorithms are presented with various theoretical properties. Connections to principal-component and maximum likelihood estimation are made, as well as suggestions for rules to choose the proper rank of the final model. 相似文献
109.
V. Spitzer S. A. de L. Bordignon E. P. Schenkel F. Marx 《Journal of the American Oil Chemists' Society》1994,71(12):1343-1348
In addition to some usual fatty acids, the seed oil ofJodina rhombifolia (Santalaceae) contains nine acetylenic fatty acids [9-octadecynoic acid (stearolic acid) (1.1%),trans-10-heptadecen-8-ynoic acid (pyrulic acid) (20.1%), 7-hydroxy-trans-10-heptadecen-8-ynoic acid (2.3%),trans-10,16-heptadecadien-8-ynoic acid (0.7%), 7-hydroxy-trans-10,16-heptadecadien-8-ynoic acid (0.1%),trans-11-octadecen-9-ynoic acid (ximenynic acid) (20.3%), 8-hydroxy-trans-11-octadecen-9-ynoic acid (12.2%),trans-11,17-octadecadien-9-ynoic acid (1.5%), 8-hydroxy-trans-11,17-octadecadien-9-ynoic acid (1.3%), 9-hydroxystearic acid (<0.1%) and 9,10-epoxystearic acid (0.7%)]. The fatty acids
have been analyzed by gas chromatography/mass spectrometry of their methyl ester and 4,4-dimethyloxazoline derivatives. The
hydroxy fatty acid methyl esters have been examined also as trimethyl-silyl ethers. Furthermore, the fatty acid methyl esters
(FAME) have been fractionated according to their polarity (FAME-A: nonhydroxy; FAME-B: hydroxy fatty acids) and to their degree
of unsaturation (FAME-A1/A2; FAME-B1/B2) by preparative thin-layer chromatography and argentation chromatography, respectively.
All of these fractions have been analyzed by ultraviolet and infrared spectroscopy, and the fractions FAME-A and FAME-B have
been analyzed further by nuclear magnetic resonance (1H,13C, 2D H/C, attached proton test) spectroscopy and gas chromatography/mass spectrometry.
This work is dedicated to the 65th birthday of Prof. Dr. K. Pfeilsticker, Institut of Food Science, University Bonn (Germany). 相似文献
110.
V. Spitzer F. Marx K. Pfeilsticker J. G. S. Maia 《European Journal of Lipid Science and Technology》1994,96(10):395-396
The mass spectra of the picolinyl derivatives of two natural occurring cyclopropenoid fatty acids (malvalic and sterculic acid) showed, besides the typical peaks for picolinyl derivatives, a characteristic gap of 66 amu between the two allylic positions of the ring system. This phenomenon could be used for the determination of the ring position of this type of fatty acids. 相似文献