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Ohne ZusammenfassungMitteilung aus dem Labatorium für angewandte Chemie der Kgl. Universität München.  相似文献   
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ABSTRACT

The instrumental setup used for simultaneous bipolar ion detection in on-line single-particle analysis by laser mass spectrometry is described. Particle size calibration has been performed using aerodynamic time-of-flight techniques. Mass spectra of several hundred ambient particles with aerodynamic diameters of 0.8 μm have been evaluated for statistical classification (Principal Components Analysis [PCA]) in order to identify main chemical components of the prominent particle classes.  相似文献   
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The sintering and graphitization behavior of mesocarbon microbeads (MCMB) at high temperatures (1900-2800 K) is investigated. It is shown that while the low temperature sintering performance of MCMB is unique, at high temperature it appears to be similar to that of conventional materials. In contrast, the obtained activation energy for MCMB high-temperature graphitization is ∼100 kcal/mol, which is smaller than that (∼240 kcal/mol) for typical carbon systems. It is concluded that the combination of such unique properties as excellent compressibility, low temperature sinterability, and rapid graphitization makes MCMB an attractive precursor for manufacturing carbon-based materials.  相似文献   
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A broad variety of juridical requirements has to be considered during the development of Web-applications. Disregard of these requirements holds severe financial dangers. A complete compilation of juridical requirements is complicated due to the multitude of juridical areas and the variety of Web-applications. Therefore, a development-driven juridical framework is suggested. From a software engineering point of view it is crucial to capture requirements at an early stage of development in order to avoid much higher costs at a later time. Thus, specialized conceptual modelling methods are examined with regard to their capability to model juridical requirements. A lack of methodical support is identified which is addressed by a systematic adaption and extension of the eW3DT method.  相似文献   
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This study tested the reliability and validity of a diagnostic thermal vascular test (TVT) for patients with Raynaud's Phenomenon (RP). The TVT examined digital blood pressure responses to combined cooling and occlusion and was developed as part of the Raynaud's Treatment Study, a multicenter clinical trial comparing the efficacy of biofeedback and pharmacological treatment. A computerized system permitted efficient, accurate, and uniform testing at different geographical sites. A comparison of 199 patients with RP and 52 healthy controls is reported. The TVT showed a sensitivity of 79% and a specificity of 88%. Test–retest reliability was acceptable (r?=?.80). Addition of a psychological challenge failed to improve the discrimination between patients with RP and controls. The TVT separated patients with RP and controls as well as or better than existing tests and did so with enhanced ease of operation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This article reviews the current bibliographic knowledge on early neurobehavioral development and milestones in Fragile X syndrome (FraX), with emphasis on males affected by the condition. Three broad areas of early development were examined: (1) gross and fine motor, (2) speech and language, and (3) social. The result of the current review indicates very limited information on the developmental milestones in all three areas. The scarce literature on motor development shows that in FraX there is an early developmental delay. Research on speech and language demonstrates pervasive deficits in conversational skills and severe developmental delay, with increasing discrepancy between language level and chronological age in young males with FraX. Finally, deficits in social development in FraX include abnormal gaze, approach and avoidance conflict, and high incidence of autistic spectrum disorders.  相似文献   
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