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Chernozems in Austria A general review of the types (Tschernosem, Paratschernosem, Feuchtschwarzerde, Gebirgsschwarzerde) and subtypes of Austrian Chernozems is given. The regional distribution of these soils in the eastern drylands (Pannon) and the dry valleys of the central alpine region is shown and their pedogenetic characteristics, genesis and systematical definition within the Austrian Soil Taxonomy is explained. 相似文献
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Igor I. Solar Edward M. Donaldson George A. Hunter 《Aquaculture (Amsterdam, Netherlands)》1984,42(2):129-139
The oral administration of 17α-methyltestosterone (MT) to wild rainbow trout fry at concentrations ranging from 1 to 100 mg/kg diet for periods up to 120 days following swim-up produced male-female ratios substantially different from controls. 100% males were produced with low MT doses (1, 3 and 9 mg/kg diet) administered for 60 days. High proportions (79–90%) of sterile rainbow trout were obtained with greater doses of the steroid (25, 50 and 100 mg/kg diet) fed for 120 days. A paradoxical feminizing effect at high doses of MT (50 and 100 mg/kg diet) was observed irrespective of the length of the treatment. No dose-related mortality during the treatments was observed. 相似文献
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不同节位摘顶对日光温室厚皮甜瓜叶片衰老的影响 总被引：2，自引：0，他引：2
以日光温室栽培的蜜世界、鲁厚甜2号厚皮甜瓜品种为试材,通过分析不同摘顶植株叶片可溶性蛋白质(Pr)、叶绿素(Chl)、丙二醛(MDA)含量以及过氧化物酶(POD)活性变化,探讨了不同节位摘顶对厚皮甜瓜叶片衰老的影响。结果表明,在授粉后7d以内,两品种第18节、24节摘顶可使座瓜节位叶片维持较高的生理活性,第30节摘顶则明显偏低,表现为：前者叶片Pr、Chl含量明显高于后者,而MDA含量、POD活性则较低。授粉14d之后,两品种第24节摘顶延缓叶片衰老的效果明显优于第18节、30节摘顶。植株摘顶后,不同节位叶片生理指标的变化进一步证实,第24节摘顶可明显延缓叶片衰老。综合分析表明,24节左右为厚皮甜瓜合理摘顶节位,早熟品种可适当提高摘顶节位,而中晚熟品种应适当降低节位。 相似文献
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G. Osterc M. Štefančič A. Solar F. Štampar 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):162-168
Abstract In this experiment, we studied the possible involvement of various phenolic acids in the rooting process of two chestnut hybrid clones (Marsol and Maraval Castanea crenata×C. sativa). The phenolic acids were measured in the cutting bases (root emergence zone) and in the cutting leaves. In the cutting bases, several hydroxycinnamic acids (caffeic, sinapic, ferulic and p-coumaric acid), chlorogenic and ellagic acids were observed, whereas in the cutting leaves only chlorogenic and ellagic acid were investigated. Cutting leaves of the Maraval clone contained a nearly 10 times higher concentration of chlorogenic and seven times higher concentration of ellagic acids than the Marsol clone (lower rooting capacity). In the cutting bases of the Marsol clone, overaccumulation of hydroxycinnamic acids occurred in the period of four days after having been placed in the substrate. During the same period, the concentrations of these acids in the Maraval clone decreased significantly. 相似文献
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Colaric M Veberic R Solar A Hudina M Stampar F 《Journal of agricultural and food chemistry》2005,53(16):6390-6396
Phenolic acids (chlorogenic, caffeic, p-coumaric, ferulic, sinapic, ellagic, and syringic acid) as well as syringaldehyde and juglone were identified in ripe fruits of 10 walnut cultivars: Adams, Cisco, Chandler, Franquette, Lara, Fernor, Fernette, Alsoszentivani 117 (A-117), Rasna, and Elit. Analyses were done using a high-performance liquid chromatograph equipped with a diode array detector. Significant differences in the contents of identified phenolics were observed among cultivars. Phenolics were determined separately in the kernel and in the thin skin of the walnut, termed the pellicle. Not only in the kernel but also in the pellicle did syringic acid, juglone, and ellagic acid predominate (average values of 33.83, 11.75, and 5.90 mg/100 g of kernel; and 1003.24, 317.90, and 128.98 mg/100 g of pellicle, respectively), and the contents of ferulic and sinapic acid (average values of 0.06 and 0.05 mg/100 g of kernel and 2.93 and 2.17 mg/100 g of pellicle, respectively) were the lowest in all cultivars. The highest differences in the sum of all identified phenolics were observed between Rasna and Fernette fruits; in Rasna there were >2-fold higher contents of identified phenolics in both kernel and pellicle. It was found that the walnut pellicle is the most important source of walnut phenolics. The ratio between the contents in pellicle and kernel varied by at least 14.8-fold for caffeic acid (cv. Adams) and by up to 752.0-fold for p-coumaric acid (cv. Elit). 相似文献
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Riboflavin and 12 of its derivatives have been shown to form solvated electrons under ultraviolet irradiation (253.7 nanometers) in various water-methanol solvent mixtures. The highest quantum yield of solvated electrons (about 0.03) was obtained for flavins containing tyrosine on a side chain in the isoalloxazine N-3 or N-10 position. The splitting of hydrogen atoms from excited flavin molecules was also observed. From the results presented here, it can be determined that the semiquinone transients are formed not only by way of the flavin triplet, as usually suggested, but also by the attack of the electrons and hydrogen atoms on flavin molecules in the ground state. This is important, because the flavin radicals remaining after the electron-ejection or hydrogen-splitting processes must also be considered in the subsequent reaction mechanisms. The electron-ejection process from electronically excited flavins has important implications in the photobiology of these compounds. 相似文献
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M. Rocio Rodríguez-Barroso José Luis García-Morales Milagrosa Ramírez-del Solar Eduardo Blanco José María Quiroga 《Water, air, and soil pollution》2010,208(1-4):173-182
Thermogravimetry (TG) was used to investigate the pollution on marine sediments close to urban and industrial sites. Sediment weight loss when heated (TG) was performed under oxidizing conditions from 250°C to 900°C. The first derivative of TG curves was used to generate a Cartesian diagram for sediments cataloging, in a quick way, according to their organic matter and grain size contents. Thus, sediment placed at the right of the diagram were characterized by a prevalence of the thin fraction and high organic matter content, while on the left side, samples were characterized by large sandy fractions, and, in general, low organic matter contents. Two references materials and metal pollution index were used to validate the Cartesian diagram obtained. 相似文献
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K. E. Wainwright M. Lagunas‐Solar M. A. Miller B. C. Barr A. C. Melli A. E. Packham N. Zeng T. Truong P. A. Conrad 《Zoonoses and public health》2010,57(1):74-81
Toxoplasma gondii, a ubiquitous parasitic protozoan, is emerging as an aquatic biological pollutant. Infections can result from drinking water contaminated with environmentally resistant oocysts. However, recommendations regarding water treatment for oocyst inactivation have not been established. In this study, the physical method of radiofrequency (RF) power was evaluated for its ability to inactivate T. gondii oocysts in water. Oocysts were exposed to various RF energy levels to induce 50, 55, 60, 70 and 80°C temperatures maintained for 1 min. Post‐treatment oocyst viability was determined by mouse bioassay with serology, immunohistochemistry and in vitro parasite isolation to confirm T. gondii infections in mice. None of the mice inoculated with oocysts treated with RF‐induced temperatures of ≥60°C in an initial experiment became infected; however, there was incomplete oocyst activation in subsequent experiments conducted under similar conditions. These results indicate that T. gondii oocysts may not always be inactivated when exposed to a minimum of 60°C for 1 min. The impact of factors such as water heating time, cooling time and the volume of water treated must be considered when evaluating the efficacy of RF power for oocyst inactivation. 相似文献