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11.
Erwin Stresemann 《Journal of Ornithology》1938,86(3):425-431
Ohne Zusammenfassung 相似文献
12.
Erwin Janchen 《Plant Systematics and Evolution》1919,68(8-10):254-286
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Erwin Stresemann 《Journal of Ornithology》1943,91(2-3):305-324
Ohne ZusammenfassungVortrag, gehalten auf der 61. Jahresversammlung der D. O. G. am 3. Juli 1943. 相似文献
15.
Didier Arseguel Armand Lattes Michel Baboul ne 《Biocatalysis and Biotransformation》1990,3(3):217-225
Horseradish peroxidase was chemically conjugated on its carbohydrate moieties with short aliphatic chains (C8 and C16). An analytical method using FT.IR spectroscopy was developed to analyze this alteration in enzyme structure. This method is non-destructive, and can be applied directly to samples of the reaction mixture. More general applications of this technique are described and discussed. 相似文献
16.
Effect of Phosphate on the Corrosion of Carbon Steel and on the Composition of Corrosion Products in Two-Stage Continuous Cultures of Desulfovibrio desulfuricans 总被引:9,自引:4,他引:5 下载免费PDF全文
Paul J. Weimer Margaret J. Van Kavelaar Charles B. Michel Thomas K. Ng 《Applied microbiology》1988,54(2):386-396
A field isolate of Desulfovibrio desulfuricans was grown in defined medium in a two-stage continuous culture apparatus with different concentrations of phosphate in the feed medium. The first state (V1) was operated as a conventional chemostat (D = 0.045 h−1) that was limited in energy source (lactate) or phosphate. The second stage (V2) received effluent from V1 but no additional nutrients, and contained a healthy population of transiently starved or resting cells. An increase in the concentration of phosphate in the medium fed to V1 resulted in increased corrosion rates of carbon steel in both V1 and V2. Despite the more rapid corrosion observed in growing cultures relative to that in resting cultures, corrosion products that were isolated under strictly anaerobic conditions from the two culture modes had similar bulk compositions which varied with the phosphate content of the medium. Crystalline mackinawite (Fe9S8), vivianite [Fe3(PO4)2 · 8H2O], and goethite [FeO(OH)] were detected in amounts which varied with the culture conditions. Chemical analyses indicated that the S in the corrosion product was almost exclusively in the form of sulfides, while the P was present both as phosphate and as unidentified components, possibly reduced P species. Some differential localization of S and P was observed in intact corrosion products. Cells from lactate-limited, but not from phosphate-limited, cultures contained intracellular granules that were enriched in P and Fe. The results are discussed in terms of several proposed mechanisms of microbiologically influenced corrosion. 相似文献
17.
Tso-Hsin Cheng und Erwin Stresemann 《Journal of Ornithology》1961,102(2):152-153
Ohne Zusammenfassung 相似文献
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A four-month survey of perineal tumescence in 131 young female pigtail monkeys () revealed that most females had begun to swell by the time they were 3 years old. Those that had not begun to swell by that time were generally of lower weight than their peers. Those that tumesced before they were 3 years old tended to be heavier than their peers, but were not necessarily heavier than older, nonswelling females. 相似文献