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111.
The pharmacokinetics of the antidepressants amitriptyline oxide and trimipramine and their major metabolites amitriptyline, nor-triptyline and desmethyltrimipramine, were studied in twelve healthy male subjects (aged from 22 to 62 years) and twelve patients (aged from 25 to 73 years) with severe renal impairment (glomerular filtration rate < 10 ml/min). Oral single doses of 60 mg amitriptyline oxide and 50 mg trimipramine, separated by a washout period, were administered to all study participants. Blood and urine samples were collected up to 120 hours after administration. For trimipramine and desmethyltrimipramine, a new HPLC method was developed. The "Fischer Somatic and Undesired Effects Check List" was used for the assessment of adverse events. The mean plasma half-life and AUC of amitriptyline oxide and its metabolites were significantly higher in patients than in healthy adults. For trimipramine the AUC was significantly higher in patients. The plasma half-life of trimipramine was longer in patients, but statistically not significant. The maximum plasma concentrations for both drugs and metabolites were at an average distinctly higher in patients. Clearance rate of amitroptylinoxide and trimipramine also differed between the two groups. Correlating with these results a high incidence and a longer persistence (in most cases > 12 hours) and more pronounced adverse effects were noted in the patient group, whereas in volunteers adverse events were only observed up to approximately eight hours.  相似文献   
112.
Status and results of a research project are reported, which aims at developing calorimetric low temperature detectors for heavy ions. The special conditions for the detection of energetic heavy ions are discussed. The response of an aluminium transition edge calorimeter, operated at about1.5K, to the impact of heavy ions was investigated. The observed energy resolutions E/E=3.9×10–3for5.9MeV/u 208 Pb-ions, E/E=1.6×10–3for4.8MeV/u 58 Ni-ions and E/E=4.3×10–3for100MeV/u 20 Ne-ions are most probably not yet limited by the intrinsic detector resolution. The present results already represent an improvement over conventional solid state detectors and ionization chambers.  相似文献   
113.
Just how insoluble are monoterpenes?   总被引:16,自引:0,他引:16  
Prior generalizations about the ecological roles of monoterpenes may be misleading if based on the presumed insolubility of monoterpenes in water. We determined the aqueous solubility of 31 biologically active monoterpenes by gas chromatography. While hydrocarbons were of low solubility (< 35 ppm), oxygenated monoterpenes exhibited solubilities one or two orders of magnitude higher, with ranges of 155–6990 ppm for ketones and of 183–1360 ppm for alcohols. Many monoterpenes are phytotoxic in concentrations under 100 ppm, well below the saturated aqueous concentrations of oxygenated monoterpenes. Therefore, even dilute, unsaturated solutions of monoterpenes, occurring naturally in plant tissues and soil solutions, may act as potent biological inhibitors.  相似文献   
114.
Zusammenstellung von Schrifttumsangaben für die Änderung der freien Standardenthalpien der Reaktionen , Mo + O2 ? MoO2 und in Eisenschmelzen. Neubestimmung der Temperaturabhängigkeiten der Größen ΔGoCr2O3, ΔGoMoO2 und ΔGoO im Eisen bei Temperaturen zwischen 1460 bzw. 1530 und 1725 °C. Nachweis der Anwendbarkeit der neu ermittelten thermodynamischen Funktionen durch EMK-Parallelmessungen an ThO2 (Y2O3)- und ZrO2 (MgO)-Festelektrolytzellen mit Cr-Cr2O3- und Mo-MoO2-Referenzelektroden in Reineisenschmelzen bei 1600 °C. Ermittlung des Parameters pe′ der Elektronenteilleitfähigkeit für einen teilstabilisierten ZrO2-Festelektrolyten mit einem Stoffmengengehalt von 5% MgO.  相似文献   
115.
The temperature dependent spectral gain in InGaN-GaN multiple quantum-well structures with 10% In content is investigated. Mode gain is measured in a temperature range between 239 K and 312 K using the Hakki-Paoli technique and compared to simulations. The simulation accounts for temperature-dependent polarization dephasing, and hence homogeneous broadening, in a rigorous fashion, without any fit parameter. It is found that the evolution of the gain spectrum with temperature at different drive currents can be modeled using a temperature-independent single value for inhomogeneous broadening. The resulting compositional fluctuations are compared to structural measurements.  相似文献   
116.
During and after rolling or flattening of metal strips and plates the permissible deviations from flatness are described by the permissible absolute wave height and the flatness index. Both values can be determined on a measuring table while the material is not subjected to global tension. Because this procedure is expensive, time‐consuming and allows measurement only at discrete positions along the strip length, on‐line flatness measuring systems are used which can detect the distribution of longitudinal tensile stresses distributed across the strip width allowing for the calculation of the flatness index. This value does not always agree with the value obtained directly by measuring on the table even when the measurement of the longitudinal tensile stress distribution operates perfectly. It can be shown that the measurement of the tensile stress distribution does not give a direct indication on the wave height in the tension‐free state determined on the measuring table. To explain the relationship between tensile stress distribution in the strip and the flatness measurement on the measuring table, the buckling behavior is analysed both with and without dead load for simple symmetrical residual stress distributions resulting, e.g., from the rolling process. Based on the knowledge of the distribution of the longitudinal residual stresses across the strip width, the flatness index and the wave height can be determined by using a specialized finite element model. If the direct measurement is performed under action of dead load, large differences between the directly and indirectly obtained flatness index are observed. Below a certain limit of the intensity of the residual stress distribution the strips and plates lie flat on the measuring table. Above this limit the strip lying on the table exhibits post‐bucking deformations. In the latter case, the wave height increases with strip thickness and intensity of residual stresses.  相似文献   
117.
This paper describes a theoretical model and related computational methods for examining the influence of inhomogeneous material properties on the crack driving force in elastic and elastic-plastic materials. Following the configurational forces approach, the crack tip shielding or anti-shielding due to smooth (e.g. graded layer) and discontinuous (e.g. bimaterial interface) distributions in material properties are derived. Computational post-processing methods are described to evaluate these inhomogeneity effects. The utility of the theoretical model and computational methods is demonstrated by examining a bimaterial interface perpendicular to a crack in elastic and elastic-plastic compact tension specimens.  相似文献   
118.
In this paper analytic formulae are derived to estimate conservatively the unavailability of a two out of four digital safety Instrumentation and Control (I&C) system with recurrent tests. The analytic formulae disclose the influence of the different parameters on the system’s unavailability. In particular, the choice of a proper test interval is essential to guarantee the required low unavailability. The extraordinary self-checking capabilities of digital systems are taken into account by use of an appropriate failure model together with the treatment of dependent failures of the integrated software–hardware system. The underlying methodology is approved by licensing experts of nuclear facilities in Germany.  相似文献   
119.
 Fabrication of high aspect ratio structures requires the use of a photoresist able to form a mold with vertical sidewalls. Thus the photoresist should have a high selectivity between the exposed and the unexposed area in the developer. It should be relatively free from stress when applied in thick layers necessary to make high aspect ratio structures. PMMA (Poly Methyl Methacrylate) is the photoresist of choice in the LIGA process, mainly for its ability to hold vertical sidewalls for tall structures. It is applied to the substrate by a glue-down process in which a pre-cast, high molecular weight, sheet of PMMA is attached to the plating base on a substrate. The applied photoresist is then milled down to the precise height by a fly-cutter prior to pattern transfer by x-ray exposure. The requirement that the applied layer be relatively free from stress dictates the choice of glue-down over casting. The substrate preparation steps, as well as the conditioning of the PMMA sheet prior to the glue-down, are done, in part, to reduce the stress in the glued down sheet of photoresist. The cutting of the PMMA sheet in the fly-cutter requires specific operating conditions as well as particular cutting tools to avoid introducing any stress and the resultant crazing of the photoresist. Received: 25 August 1997/Accepted: 3 September 1997  相似文献   
120.
 Various optical or x-ray applications require reduction of scattered radiation on the imaging detector to produce sharper images. The scattered radiation is reduced when the radiation impacting on the detector is from a chosen small solid angle. This requires a mask in front of the detector with small holes and high aspect ratio. We are applying the SLIGA process to perform a proof-of-principle demonstration with the capability of making a large and high area anti-scattering grid. The approach is by assembling and stacking small pieces of grid. To maintain high throughput of the desired radiation, the wall of the grid has to be thin. We designed and fabricated four grid patterns all with 20 μm thick walls and 80 μm×80 μm holes. The individual pieces were 210 μm high and made of nickel. The pieces were assembled and stacked to make a 5 mm×5 mm grid 2.1 mm high. Much larger grids can be made by the SLIGA process, which was chosen because of its capability to fabricate high aspect ratio devices with precision. Received: 25 August 1997/Accepted: 24 October 1997  相似文献   
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