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31.
A high voltage layered Li1.2Ni0.16Co0.08Mn0.56O2 cathode material with a hollow spherical structure has been synthesized by molten-salt method in a NaCI flux. Characterization by X-ray diffraction and scanning electron microscopy confirmed its structure and proved that the as-prepared powder is constituted of small, homogenously sized hollow spheres (1-1.5 μm). The material exhibited enhanced rate capability and high first cycle efficiency due to the good dispersion of secondary particles. Galvanostatic cycling at different temperatures (20, 40, and 60 ℃) and a current rate of 2 C (500 mA.g-1) showed no significant capacity fade.  相似文献   
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This contribution presents a fracture mechanics safety analysis with finite element models applied on I-beams with defects in the tension flange. The moment rotation at room temperature was observed in the light of the toughness behaviour in front of initial notches. The results show very early crack initiation due to very large initial defects. The experiments were accompanied by a fracture mechanics safety analysis employing FEM. However, in temperature ranges of buildings plastically designed beams are subjected to sufficient rotation capacity, i.e. rotational ductility could be found.  相似文献   
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An integrated LTCC laminated waveguide-to-microstrip line T-junction   总被引:1,自引:0,他引:1  
In this paper, an integrated low-temperature co-fired ceramic (LTCC) laminated waveguide to microstrip line T-junction is proposed and experimentally verified. A multilayer bell-shape probe end comprising multiple parallel metallic pads is used to improve the bandwidth and matching condition. The experimental result shows good correlation with the simulated result. The configuration can also be used as the transition between microstrip line and laminated waveguide.  相似文献   
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Erörterung der physikalischen Verhältnisse an den Düsenmündungen, Ableitung der Strömungsgesetze unter Berücksichtigung der Reibung, Berechnung der erforderlichen Druckverhältnisse und Rohrquerschnitte. Auslegung, Projektierung und Optimierung von Düsen für die Praxis. Betriebskennlinienumrechnung auf verschiedene Gasarten. Vorgehen bei der Auswertung von Meßergebnissen. Bestimmung von Reibungsbeiwerten. Vergleich der Verhältnisse bei reibungsbehafteter (wirklicher) Strömung und einer gedachten reibungsfreien (isentropen) Strömung.  相似文献   
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The calorie intake of patients with advanced cancer   总被引:1,自引:0,他引:1  
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Our aim was to investigate the contribution of decidual macrophages, which constitute an important immune component of the decidua in late gestation, to intrauterine defence mechanisms. Using flow cytometry we examined the ability of decidual macrophages, isolated from term decidua, to bind and phagocytose fluorescence-labelled bacterial and yeast bioparticles. We also assessed their ability to generate superoxide radicals and tumour necrosis factor-alpha following lipopolysaccharide challenge. Decidual macrophages bound bacterial and yeast particles in a dose-dependent manner, which subsequently led to phagocytosis. These macrophages also produced superoxide radicals and the pro-inflammatory cytokine TNF-alpha when challenged with bacterial lipopolysaccharides. These results suggest a role for decidual macrophages in pathogen recognition and clearance during pregnancy, and, therefore, they are likely to protect the fetus against intrauterine infections which might otherwise lead to preterm labour.  相似文献   
40.
A new screening method for the detection and identification of GMO, based on the use of multiplex PCR followed by microarray, has been developed and is presented. The technology is based on the identification of quite ubiquitous GMO genetic target elements first amplified by PCR, followed by direct hybridisation of the amplicons on a predefined microarray (DualChip® GMO, Eppendorf, Germany). The validation was performed within the framework of a European project (Co-Extra, contract no 007158) and in collaboration with 12 laboratories specialised in GMO detection. The present study reports the strategy and the results of an ISO complying validation of the method carried out through an inter-laboratory study. Sets of blind samples were provided consisting of DNA reference materials covering all the elements detectable by specific probes present on the array. The GMO concentrations varied from 1% down to 0.045%. In addition, a mixture of two GMO events (0.1% RRS diluted in 100% TOPAS19/2) was incorporated in the study to test the robustness of the assay in extreme conditions. Data were processed according to ISO 5725 standard. The method was evaluated with predefined performance criteria with respect to the EC CRL method acceptance criteria. The overall method performance met the acceptance criteria; in particular, the results showed that the method is suitable for the detection of the different target elements at 0.1% concentration of GMO with a 95% accuracy rate. This collaborative trial showed that the method can be considered as fit for the purpose of screening with respect to its intra- and inter-laboratory accuracy. The results demonstrated the validity of combining multiplex PCR with array detection as provided by the DualChip® GMO (Eppendorf, Germany) for the screening of GMO. The results showed that the technology is robust, practical and suitable as a screening tool.  相似文献   
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