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排序方式: 共有368条查询结果,搜索用时 15 毫秒
1.
Johann Lepschy-v. Gleissenthal Richard Dietrich Erwin Märtlbauer Manfred Schuster Adalbert Süß Gerhard Terplan 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,188(6):521-526
Summary Bavarian cereals and wheat flour from the 1987 harvest were analysed for nivalenol (NIV) and deoxynivalenol (DON) using high performance liquid chromatography (HPLC) and for T-2 toxin and zearalenone (ZEA) by enzyme-linked-immunosorbent as say (ELISA). The study included 190 field samples of wheat, barley, rye and oat with visibly damaged ears, 45 samples of wheat intended for feed production and two series of wheat flour (type 550) and whole wheat flour collected in October 1987 and June 1988. The field samples examined showed a high DON contamination of wheat (87%) with an average of 3.96 mg/kg and a maximum of 43.8 mg/kg. Mean levels between 0.33 mg/kg and 0.27 mg/kg DON could be detected in barley, rye and oat. Of the wheat samples, 58% contained ZEA with a maximum of 1.560 mg/kg. The highest levels of ZEA were detected in samples which also showed high concentrations of DON. The NIV and T-2 toxin levels were comparatively low. Thirty percent of the samples showed NIV concentrations between 0.04 mg/kg and 0.29 mg/kg and 38% contained between 0.005 and 0.60 mg/kg of T-2. In the wheat samples for feed production, only DON was detected with an average of 0.190 mg/kg and a maximum of 0.75 mg/kg. The highest DON levels (0.58 mg/kg) from October 1987 were found in the wheat flour samples which were lower than the highest DON concentration (3.24 mg/kg) detected in the samples collected during June 1988. This fact was probably due to a substantial amount of non-contaminated wheat from 1986. The toxin concentrations in the whole wheat flour were not higher than in the type 550 flour. The regional distribution of the mean DON concentrations showed the highest levels in Middle and Lower-Franconia.
Vorkommen von Fusarium Mykotoxinen in bayerischem Getreide der Ernte 1987
Zusammenfassung Cerealien und Weizenmehle der bayerischen Ernte 1987 wurden mittels hochauflösender Flüssigchromatographie (HPLC) auf Nivalenol (NIV) und Deoxynivalenol (DON) Bowie mit Enzymimmunoassay auf T-2 Toxin und Zearalenon (ZEA) analysiert. Die Untersuchungen umfaßten 190 Feldproben von Weizen, Gerste, Roggen und Hafer, die alle optisch erkennbaren Fusarienbefall aufwiesen, 45 Futterweizenproben Bowie zwei Probenserien von Weizenmehlen der Type 550 und Vollkornweizenmehlen, die im October 1987 und im Juni 1988 gezogenwurden. — Die Untersuchungen der Feldproben ergaben eine hohe DON-Kontamination des Weizens (87%) mit einem durchschnittlichen Gehalt von 3,96 mg/kg und einem Maximalgehalt von 43,8 mg/kg. In Gerste, Roggen und Hafer konnten durchschnittlich zwischen 0,33 mg/kg und 0,27 mg/kg DON-nachgewiesen werden. 58% der Winterweizenproben wiesen Zearalenon mit einem Maximalgehalt von 1,56 mg/kg auf. Die höchsten ZEA-Werte wurden in Proben ermittelt, die gleichzeitig einen hohen DON-Gehalt aufwiesen. Die Konzentrationen von NIV und T-2 Toxin waren vergleichsweise niedrig. 30% der Proben hatten NIV-Gehalte zwischen 0,04 mg/kg und 0,29 mg/kg und 38% enthielten T-2 Toxin zwischen 0,005 mg/kg und 0,06 mg/kg. In den Futterweizenproben konnte DON als einziges Toxin mit einem Gehalt von durchschnittlich 0,19 mg/kg und maximal 0,75 mg/kg festgestellt werden. Die Weizenmehle, die im October 1987 gezogen wurden, wiesen maximal 0,58 mg/kg DON auf. Die Gehalte lagen damit medriger als die der Mehlproben vom Juni 1988, die maximal 3,24 mg/kg und durchschnittlich 0,26 mg/kg DON enthielten. Dieser Sachverhalt könnte auf Anteile von nicht kontaminiertem Weizen der Ernte 86 an den im October gezogenen Mehlproben zurückgeführt werden. Die Toxingehalte der Vollkornmehle waren nicht höher als die der Weizenmehle der Type 550. Die höchsten Durchschnittsgehalte von DON wurden in Mittel- und Unterfranken festgestellt.相似文献
2.
Rainwater collection as a possible water source in developing countries is introduced. The major parameters in calculating the size of the tank are defined. Six methods that have been used previously to relate demand, storage, reliability and the rainfall pattern are compared to the Ottawa Model over a wide range of demands. 相似文献
3.
Giant Electric Dipole Resonance (GDR) parameters for γ decay to excited states with finite spin and temperature are compiled. Over 100 original works have been reviewed and from some 70 of them, about 350 sets of hot GDR parameters for different isotopes, excitation energies, and spin regions have been extracted. All parameter sets have been brought onto a common footing by calculating the equivalent Lorentzian parameters. The current compilation is complementary to an earlier compilation by Samuel S. Dietrich and Barry L. Berman (At. Data Nucl. Data Tables 38 (1988) 199-338) on ground-state photo-neutron and photo-absorption cross sections and their Lorentzian parameters. A comparison of the two may help shed light on the evolution of GDR parameters with temperature and spin. The present compilation is current as of July 2006. 相似文献
4.
Rogier Schonenborg Adalberto Costessi Peter Schiller 《Microgravity science and technology》2007,19(5-6):219-224
This paper gives a quick overview of how various scientific, operational and safety related requirements drove the development of hardware for the Bone Proteomics (BOP) experiment that was conducted on the International Space Station during the Italian Soyuz Mission in 2005. The experiment objectives will be highlighted briefly and design solutions will be presented. Comments will be given regarding the choice of a particular design solution and the impact on the complexity, cost and development time. Conclusions in this paper are based on the experience gained when developing the BOP experiment hardware and other relatively small experiment hardware packages, typical of European Soyuz Missions. The observations should not be extrapolated to large payloads. The objective of this paper is not to produce a recipe for developing experiment hardware; dedicated documents for that purpose are available elsewhere. Rather, the objective is to help others profit from experience gained in the development of relatively small experiment hardware packages, and to highlight where time and cost saving decisions can be made. 相似文献
5.
L. Ponsatí V. Acuña I. Aristi M. Arroita E. García‐Berthou D. von Schiller A. Elosegi S. Sabater 《河流研究与利用》2015,31(8):1003-1016
Dams regulate downstream hydrology and modify water quality, which in turn can impinge on the biota, especially in rivers naturally subject to large hydrological variability, such as those under Mediterranean climate. The effect of dams on biofilms was analysed in three tributaries (Cinca, Siurana and Montsant) of the Ebro River (NE Spain). We hypothesized that flow regulation would lead to lower spatial variability of biofilms on the streambed and to a decrease in their metabolic rate per unit biomass, especially during low flow periods. Biofilm characteristics were studied in five transects evenly spaced along river reaches upstream (control) and downstream (impact) of dams in each river, along with riverbed granulometry, hydraulics and water chemistry. Chlorophyll‐a, respiratory activity, photosynthetic capacity and efficiency, and extracellular enzymatic activities (β‐d ‐glucosidase, alkaline phosphatase and leucine‐amino‐peptidase) of epilithic biofilms were measured in different seasons. Spatial variability of chemical and biological variables was reduced downstream of the dams. Chlorophyll‐a concentration, photosynthetic efficiency and respiration capacity were higher in impact than in control reaches, but generally, low inorganic phosphorus concentrations resulted in comparable phosphatase activities downstream and upstream of dams. On the other hand, β‐d ‐glucosidase and leucine‐amino‐peptidase activities were higher at impact reaches. Biofilms were thicker and metabolically more active at the impact reaches, with higher ability to transform dissolved organic matter. Overall, results from this study provide evidence that dams can largely affect the structure and activity of river biofilms, with foreseeable important consequences for river ecosystem functioning. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
6.
N. M. Sitnikov V. A. Yushkov A. A. Afchine L. I. Korshunov V. I. Astakhov A. E. Ulanovskii M. Kraemer A. Mangold C. Schiller F. Ravegnani 《Instruments and Experimental Techniques》2007,50(1):113-121
A fluorescent airborne stratospheric hygrometer (FLASH) for precise water vapor measurements on board a high-altitude airplane in the upper troposphere and the lower stratosphere has been developed and produced at the Central Aerological Observatory. The range of measured water vapor concentrations is 0.5–300 ppmv at altitudes of 8–21 km. The results of laboratory tests of the instrument are compared to the data of the other hygrometers. Some results of water vapor measurements on board the Geofizika M55 high-altitude airplane in different regions of the Earth are presented. 相似文献
7.
This paper presents the first (randomized) algorithm for implementing self-stabilizing group communication services in an asynchronous system. Our algorithm converges rapidly to legal behavior and is communication adaptive, namely, the communication volume is high when the system recovers from the occurrence of faults and is low once a legal state is reached. Communication adaptability is achieved by a new technique that combines transient fault detectors. 相似文献
8.
V. Barale Corresponding author C. Schiller C. Villacastin R. Tacchi 《International journal of remote sensing》2013,34(7-8):1363-1370
A long-term time series of Advanced Very High Resolution Radiometer (AVHRR) (1981–1999) data has been used to assess the main physical features in the Adriatic Sea. Individual images were processed to estimate Sea Surface Temperature (SST) values, to create long-term composite fields (weekly, monthly, seasonal scales), and to derive basic statistics for the Northern, Central and Southern regions, each split again into an Eastern and a Western section. At the basin scale, an apparent general warming trend can be recognized in the time series. The linear fit to the seasonal cycles suggests an increase of about 2°C in 20 years, essentially due to a steady rise of summer values. A general north–south gradient can be found during winter, the Northern sections being colder than the Southern ones. An east–west gradient appears during summer, the Western sections being warmer then their Eastern ones. The Northern Adriatic exhibits substantial fluctuations, possibly linked to the cycle of winter cooling and summer warming in the relatively shallow sub-basin. The North Western section shows larger fluctuations than the North Eastern one, with lower winter SST, probably due to the freshwater inflow from the Po River delta. The Southern Adriatic exhibits less variability, possibly influenced by the periodic water exchanges with the Ionian Sea. The South Eastern section shows somewhat larger fluctuations than the South Western one, with higher winter SST, probably due to the inflow of warmer waters from the south. The two Central sections reveal patterns similar to the ones of the whole basin. The observed temperature patterns appear to follow the classical Adriatic cyclonic circulation scheme. 相似文献
9.
Perovskite-type LaMnO3 powders and coatings have been prepared by a novel technique: reactive suspension plasma spraying (SPS) using an inductively
coupled plasma of approximately 40 kW plate power and an oxygen plasma sheath gas. Suitable precursor mixtures were found
on the basis of solid state reactions, solubility, and the phases obtained during the spray process. Best results were achieved
by spraying a suspension of fine MnO2 powder in a saturated ethanol solution of LaCl3 with a 1 to 1 molar ratio of lanthanum and manganese. A low reactor pressure was helpful in diminishing the amount of corrosive
chlorine compounds in the reactor. As-sprayed coatings and collected powders showed perovskite contents of 70 to 90%. After
a posttreatment with an 80% oxygen plasma, an almost pure LaMnO3 deposit was achieved in the center of the incident plasma jet.
This paper originally appeared in Thermal Spray: Meeting the Challenges of the 21st Century; Proceedings of the 15th International Thermal Spray Conference, C. Coddet, Ed., ASM International, Materials Park, OH, 1998. This proceedings paper has been extensively reviewed according
to the editorial policy of the Journal of Thermal Spray Technology. 相似文献
10.