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21.
About Sulfur Containing Glycosides of Rape Seeds – Analysis by Thermospray Technique/Mass Spectrometry The HPLC is the method of choise for the estimation of glucosinolates occurring in rape seeds. But in comparison to GC a disadvantage is that the HPLC fractions can't be analyzed by MS directly. Such possibility is opened now with the thermospray technique. It allows to introduce the HPLC fractions immediately into the mass spectrometer system. Based on the first application of this technique to glucosinolates published by Mellon et al. (1987) the fundamentals of the thermospray technique/mass spectrometry are presented, the experimental details are explained and the characteristic ions of the thermospray mass spectra of 12 glucosinolates (desulfo derivatives) are discussed. The analytical performance of the method is examined also. 相似文献
22.
A. Celaya Sanfiz T. W. Hansen F. Girgsdies O. Timpe E. Rödel T. Ressler A. Trunschke R. Schlögl 《Topics in Catalysis》2008,50(1-4):19-32
This work presents a detailed investigation of the preparation of MoVTeNbO x catalysts by hydrothermal synthesis. Phase-pure synthesis of M1 has been achieved applying the metals in a molar ratio Mo/V/Te/Nb = 1/0.25/0.23/0.12. Raman, UV/Vis spectroscopy, and SEM/EDX analysis show that the elements are inhomogeneously distributed in the initial suspension that is formed after mixing the metal salts in an aqueous medium. Iso- and heteropoly anions of molybdenum, free telluric acid as well as supra-molecular polyoxometalate clusters are observed in the solution, whereas all metals have been found in the precipitate. Complete rearrangement of molecular building blocks under hydrothermal conditions is essential for formation of phase-pure materials. Optimized synthesis conditions with respect to temperature and time result in the formation of a precursor consisting of nano-structured M1 characterized by an extended periodic organization in the [001] direction and a fairly homogeneous distribution of the elements. Residual ammonium containing supra-molecular species in the precursor result in the formation of phase mixtures during the subsequent crystallization by heat treatment in inert gas. Phase-pure M1 exhibits a distinct degree of flexibility with respect to the chemical composition that becomes obvious by incorporating Nb not exclusively into pentagonal bi-pyramidal units, but also into octahedral coordinated positions as shown by EXAFS. Anisotropic growth of the needle-like M1 crystals has been observed during the final heat treatment performed at 873–923 K in inert atmosphere disclosing a potential method to control the catalytic properties of MoVTeNbO x catalysts. 相似文献
23.
A semiautomated electron backscatter diffraction technique for extracting reliable twin statistics 总被引:2,自引:0,他引:2
B. L. Henrie T. A. Mason B. L. Hansen 《Metallurgical and Materials Transactions A》2004,35(12):3745-3751
A framework has been developed for extracting reliable twin statistics from a deformed microstructure using crystallographic
twin identification techniques with spatially correlated electron backscatter diffraction (EBSD) data. The key features of
this analysis are the use of the mathematical definition of twin relationships, the inclination of the common K
1 plane at a twin boundary, and the correct identification of the parent orientation in a parent/twin pair. Methods for identifying
the parent in a parent/twin pair will be briefly discussed and compared. Twin area fractions are then categorized by operative
twin systems, number of active twin variants in each system, and corrected twin widths. These statistics are reported here
for α-zirconium samples deformed in quasi-static four-point bend beams and in a 100 m/s Taylor cylinder impact test. Analysis of
the statistics also begins to reveal the roles that deformation rate and relative orientation of the boundary conditions to
the material’s symmetry axes play in determining the twinning activity that accommodates the imposed boundary conditions.
These improved twin statistics can help quantify the deformation processes in materials that deform by twinning as well as
serve to provide better validation of proposed models of the deformation processes. 相似文献
24.
Todd Michael; Armeli Stephen; Tennen Howard; Carney Margaret Anne; Affleck Glenn 《Canadian Metallurgical Quarterly》2003,17(4):303
Data from 2 daily diary studies of stress, negative affect, and drinking were used to examine the correspondence between global self-reports of drinking to cope (DTC) and within-person stress/negative affect-drinking associations. In Study 1, 83 community-residing drinkers recorded data in nightly booklets on negative events, perceived stress, negative affect, and drinking for 60 consecutive days. In Study 2, 88 community-residing drinkers recorded data on negative events and negative interpersonal exchanges nightly and negative affect and drinking in near-real time on palmtop computers for 30 consecutive days. Both studies showed only modest correspondence between self-reported DTC and between-person differences in within-day, daily, and weekly associations between stress/negative affect and drinking. The findings indicate that individuals who report higher DTC simply may drink across a wider variety of conditions than those who report relatively lower DTC. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
Two cases of adverse reactions to intravesical treatment with bacillus Calmette-Guérin are reported. The first patient presented with a severe suppurating epididymo-orchitis three months after his last treatment. The second patient developed Reiter's disease with arthritis of one knee and conjunctivitis 1 week after the fourth instillation. 相似文献
26.
Current sanitation concepts of decentralised wastewater treatment and reuse raise the issue of monitoring and maintenance of such systems. To guarantee high quality of the recycled water, systems with high requirements concerning process technology are essential. With increasing numbers of decentralised treatment systems spread over far distances it will become more and more impossible and uneconomic to have expert personnel on site. Therefore, new visualisation and intelligent information systems are necessary. The paper describes the structure and 3D-demonstrations as a base for information visualisation. Up-to-date visualisation techniques, facilitating the cognition of context-adapted information, make it possible to maximise the amount of information presented to the user without overwhelming her or him. Concerning diagnosis and decision support systems in the domain of wastewater treatment, several interesting approaches are presented, estimating their applicability for decentralised wastewater treatment systems. The intelligent decision support system presented here consists of a combined ontology- and case-based reasoning system in addition to a process monitoring system. It is responsible for plausibility checks, error diagnosis, solution proposals, and optimisation suggestions. 相似文献
27.
28.
Lee Y.-H. Yau L.D. Hansen E. Chau R. Sabi B. Hossaini S. Asakawa B. 《Electron Devices, IEEE Transactions on》1993,40(1):163-168
It is shown that while gate oxides containing thermal/LPCVD composite oxide have lower defect densities than gates using only thermal oxides, they are more susceptible to hot-carrier degradation. The hot-carrier-induced degradation of composite oxides is worse in p-channel MOSFETs than in n-channel MOSFETs. This sensitivity of p-channel MOSFETs is caused by higher electron trapping levels in LPCVD oxides. For 150-Å gate technology, the hot-carrier-degradation resistance of thermal/LPCVD composite gate oxides with a 70-Å or thicker thermal oxide layer approaches that of high-quality pure thermal oxide 相似文献
29.
30.
B Nygaard L Hegedüs FN Bennedbaek A Veje JO Faber JE Hansen 《Canadian Metallurgical Quarterly》1998,160(37):5349-5352
Traditional treatment modalities of diffuse nontoxic goitre are thyroid hormone suppression or surgery. When treating nodular nontoxic goitre with 131I treatment, a reduction in thyroid volume to about 50% is seen. In the present study we evaluated the effect of 131I treatment in 21 patients treated for a diffuse nontoxic goitre and followed by evaluation of thyroid volume measured by ultrasound. Thyroid volume declined in all patients from median of 66 ml (range 27-160 ml) to 21 ml (9-108 ml) over a year, a reduction of 62%. Three patients developed hypothyroidism in the follow-up period (14%), one of these had a temporary hyperthyroid fase. In conclusion, 131I treatment of diffuse nontoxic goitre reduces thyroid volume by approximately 60% within 12 months. Hypothyroidism developed in 14% during a limited follow-up period. 相似文献