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11.
Helmut Reimer 《Datenschutz und Datensicherheit - DuD》2006,30(11):748-748
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Th. Hilbert und P. B?ttcher 《Holz als Roh- und Werkstoff》1985,43(6):242
Ohne Zusammenfassung 相似文献
15.
Johann Vollmann Heinrich Grausgruber Helmut Wagentristl Heinrich Wohleser Pavel Michele 《Journal of the science of food and agriculture》2003,83(15):1581-1586
The presence of protease inhibitors in soybean prohibits the utilisation of the raw beans for food and feed. However, little information is available about environmental influences and the effects of nitrogen and sulphur supply on the antinutritional constituents of soybean. As these factors may influence protease inhibitors, soybean genotypes segregated according to the presence or absence of the Kunitz trypsin inhibitor have been evaluated for trypsin inhibitor activity (TIA) in field trials. TIA was affected significantly by environment (geographical location), fertilisation treatment and genotype. Environmental means of TIA were between 69.5 and 104.8 mg g?1. Nitrogen application, which caused an increase in seed protein content, resulted in a reduction in TIA by about 15% as compared with the control. Remarkably, simultaneous application of nitrogen and sulphur in the form of ammonium sulphate had a similar reductive effect on TIA to that of nitrogen application alone, although soybean protease inhibitors are rich in sulphur amino acids. Significant genetic variation in TIA was found both within the genotype class with the Kunitz inhibitor present as well as within the class lacking this inhibitor. The results suggest that TIA of soybean may be modified considerably by genetic improvement and appropriate agronomic management. Copyright © 2003 Society of Chemical Industry 相似文献
16.
The frequencies of multinational papers in various sciences 总被引:2,自引:1,他引:1
Helmut A. Abt 《Scientometrics》2007,72(1):105-115
Multinational papers are defined here as ones written by authors who reside in different countries during the course of research.
For each of 16 fields of science, I scanned the first 200 papers in 2005 in four major journals publishing original research
papers. Those journals produced 40% of all the citations among those journals with Impact Factors greater than 1.0. The frequencies
of multinational papers ranged from 13% in surgery to 55% in astronomy. Although one can list a dozen factors which might
contribute toward multinational papers, I lack the data to test most of those. There are only minor correlations with team
sizes and Impact Factors, inadequate to explain the range. There is a larger, but not convincing, dependence upon the fractions
of single-author papers and its cause, if real, is unclear. However, the most prominent factor seems to be the nature of the
objects studied; if they are usually local (e.g. in one hospital or in one laboratory), the papers tend to be domestic but
if most of the objects are available simultaneously to scientists in many countries (e.g. the sky in astronomy or the oceans
and the Earth’s atmosphere in geosciences or widespread diseases in the area of infectious diseases or plants and animals
widely distributed in biology), the papers are often international. Auxiliary results for 2005 are an average of 5.5 ± 0.3
authors per paper and 6.6 ± 1.0% one-author papers. 相似文献
17.
Modified (α‐diimine)nickel(II) catalysts are suitable for ethylene oligomerization reactions. Due to the mechanism (“chain running”), the formation of double‐bond isomers and branched olefins can be observed. The obtained oligomer mixtures show a Schulz–Flory distribution. Increasing ethylene pressure favors the selectivity of α‐olefin formation. The same effect can be observed when Lewis bases like thiophene or furane are added to the oligomerization reaction mixture. These results can be related to an interaction of the additives with the catalytic active species during the oligomerization process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1356–1361, 2003 相似文献
18.
Lüps und Petrak 《Zeitschrift für Jagdwissenschaft》2003,49(2):159-160
Ohne Zusammenfassung 相似文献
19.
Giuseppe G. G. Manzardo Sandra Kürsteiner-Laube und Daniel Perrin 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,203(6):501-506
In diethyl ether extracts from celeriac (Apium graveolens L. var.rapaceum) all four stereoisomers of (3a–7a)-cis-3-butylhexahydrophthalide were found to be present. The analyses were carried out by means of GC, enantioselective GC and GC-MS. The assignment of the relative configuration of the diastereomers3 and4 was accomplished by NOE difference spectroscopy. 相似文献
20.