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41.
42.
The electron spin resonance (ESR) measurements were performed in single crystals of La1 ? x Sr x MnO3 (0.05 ≤ x ≤ 0.125) in order to study the interplay of crystal field, Dzyaloshinsky–Moriya interaction, Jahn–Teller (JT) effect, and orbital order. The angular dependence of the ESR linewidth of an untwinned La0.95Sr0.05MnO3 single crystal has been analyzed in the high-temperature approximation, which takes into account the microscopic geometry of the four nonequivalent Mn positions in the orthorhombic unit cell. A strong mixing of the |3z 2 ? r 2> and |x 2 ? y 2> states for the real orbital configuration was found. Magnetic inhomogeneities observed in the ESR spectra across the composition range 0.075 ≤ x ≤ 0.125 can be attributed to the presence of ferromagnetic clusters (magnetic spin polarons) in the paramagnetic state. New polaronic models are proposed.  相似文献   
43.
Summary ESCA is used to characterize ion beam irradiated P(p-ClPhMA)-samples. The results show a chlorine abstraction. The experimental findings are in accordance with a recently proposed model for a crosslinking mechanism of halogenated aromatic polymers.  相似文献   
44.
A rank- and sign-dependent utility theory is based on an operation of joint receipt of 2 independent gambles and 3 assumptions regarding the operation (R. D. Luce, 1992). The authors tested these 3 assumptions (i.e., segregation, duplex decomposition, and the additivity of certainty equivalents over joint receipt) using both judged and choice certainty equivalents (CEs). Median choice CEs provided support for both segregation and duplex decomposition but little support for additivity in gains or in losses, whereas median judged CEs also failed to support segregation. The latter failure appears to result from some Ss misunderstanding the instructions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
We performed BAEP study to evaluate acoustic nerve involvement in 102 patients affected by peripheral neuropathies of different etiology, predominantly hereditary and inflammatory acquired neuropathies. Prolonged latency of early waves, indicative of slowing in VIII nerve conduction, was found in a high percentage of cases. Abnormalities were far more frequent (44% vs 14%) and severe in patients with demyelinating rather than axonal neuropathy. Among demyelinating neuropathy, the most severe latency delay was found in Hereditary Motor and Sensory Neuropathy type III. The pattern of acoustic nerve involvement differed slightly between Hereditary Motor and Sensory Neuropathy type I and acquired inflammatory demyelinating polyradiculoneuropathy, perhaps reflecting different pathogenetic mechanisms and different sites of VIII nerve demyelination.  相似文献   
46.
47.
Attempts to model the degradation of polymer composites have been restricted to modelling the effects of selected degradation mechanisms. No comprehensive model has yet been accepted to predict the effect of the natural environment on the strength of polymer composites. From a review of available literature, it appears that the matrix of a polymer composite is most affected by exposure to the natural environment. Further, the damage appears to progress from the surface into the interior of the laminate. An approach has been developed to determine the properties of the damaged layer and combine the properties of the damaged and undamaged layer to obtain bulk material properties of the laminate.  相似文献   
48.
Far-infrared magnetotransmission measurements have been performed on MBE-grown HgTe and CdTe epilayers. The results on the HgTe samples can be understood by the standard Pidgeon-Brown model for bulk HgTe. For the CdTe layers, transitions were only observed under illumination by visible light. The spectra are dominated by the 1s→2p transition of the shallow hydrogen-like impurity. These transitions are persistent with a life time of the order of magnitude of one second.  相似文献   
49.
A new microcalorimeter with eight parallel channels using robust, low cost sensors for characterization of coatings and adhesives is described and first experiments on coatings and adhesives are presented. The calorimetric sensors are based on thin glass plates (20 mm × 20 mm, thickness 150 μm) with heater and thermocouple sputtered on the surfaces (calorimetric active area of about 9 mm2). The setup allows heating and cooling experiments as well as isothermal measurements in the temperature-modulated mode with up to eight sensors in parallel. The measured quantities are the real (Cp) and imaginary part (Cp) of the complex heat capacity (), the related absolute value of the heat capacity () and the heat flow . An industrial computer (NI PXI system) with specific software for calibration and data recording controls the electronic components. Sensors can be embedded in a temperature controlled oven (heating and cooling by Peltier elements) or alternatively in a climatic cabinet with controlled temperature and humidity.

The method has been applied successfully to monitoring of film formation of aqueous polymer dispersions (styrene-acrylate copolymer) and curing of coatings.  相似文献   

50.
Healthy Aims is a 23- million, four-year project, funded under the EU's information society technology sixth framework program to develop intelligent medical implants and diagnostic systems (www.healthyaims.org). The project has 25 partners from 10 countries, including commercial, clinical, and research groups. This consortium represents a combination of disciplines to design and fabricate new medical devices and components as well as to test them in laboratories and subsequent clinical trials. The project focuses on medical implants for nerve stimulation and diagnostic equipment based on strain-gauge technology.  相似文献   
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