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91.
The use of thermodynamic, statistical, and light and electron‐optical microscopic methods has made it possible to analyse the course of reactions during steel‐plant‐internal hot metal desulphurisation. The theoretical dependence between oxygen and sulphur activity has been used to develop an EMF‐measurement‐based technique for determining the sulphur content as the hot metal is desulphurised. The absence of magnesium sulphide from the collection of phases in the final slag because of the greater stability and secondary formation of calcium sulphide has been explained with the aid of thermo‐chemical calculations. 相似文献
92.
In 5 experiments, the authors tested whether the processing of nonconscious spatial stimulus information depends on a prior intention. This test was conducted with the metacontrast dissociation paradigm. Experiment 1 demonstrated that masked primes that could not be discriminated above chance level affected responses to the visible stimuli that masked them. Experiments 2 and 3 showed that this effect was abolished when the task instruction was changed in such a way that the primes ceased to be task relevant. Experiments 4 and 5 demonstrated that a prime's effect depended on whether it was associated with the same response as the target or with an opposite response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Low temperature silicon direct bonding for application in micromechanics: bonding energies for different combinations of oxides 总被引:3,自引:0,他引:3
Gertrud Kräuter Andreas Schumacher Ulrich Gösele 《Sensors and actuators. A, Physical》1998,70(3):100-275
Plain or structured hydrophillic silicon wafers covered with native oxide or with thermally grown oxide layers have been directly bonded at room temperature; afterwards, the samples were annealed at 100°C to 400°C. There is a significant difference in the observed bonding energy depending on the wafer pairing chosen. If one or both wafers are covered with a native oxide layer, high bonding strengths are reached even at low temperatures. This can be explained by the different diffusion behaviour of water molecules through a thick thermal oxide layer on one hand, and through a thin native oxide layer on the other hand. Two different methods for the activation of the wafer surfaces just prior to bonding are described. 相似文献
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The performance of older adults and depressed people on linear order reasoning is hypothesized to be best explained by different theoretical models. Whereas depressed younger adults are found to be impaired in generative inference making, older adults are well capable of making such inferences but exhibit problems with working memory (Experiments 1 and 2). Restriction of the available study time impairs reasoning by nondepressed control participants and. as such, proves to be a good model of older adults' but not depressed participants' limitations (Experiment 3). These results are replicated comparing depressed and older participants with a control group in the same study, providing increased power and linking the results to additional control measures of processing speed and working memory (Experiment 4). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Simon effects might partly reflect stimulus-triggered response activation. According to the response-discrimination hypothesis, however, stimulus-triggered response activation shows up in Simon effects only when stimulus locations match the top-down selected spatial codes used to discriminate between alternative responses. Five experiments support this hypothesis. In Experiment 1, spatial codes of each response differed by horizontal and vertical axis position, yet one axis discriminated between alternative responses, whereas the other did not. Simon effects resulted for targets on discriminating axes only. In Experiment 2, both spatial axes discriminated between responses, and targets on both axes produced Simon effects. In Experiment 3, Simon effects resulted for a spatial choice-reaction task but not for a go/no-go task. Even in the go/no-go task, a Simon effect was restored when a two-choice reaction task preceded the go/no-go task (Experiment 4) or when participants initiated trials with responses spatially discriminated from the go response (Experiment 5). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Confocal scanning laser microscopy (CSLM) was used to study the microcirculation of the brain neocortex in anaesthetized rats. After removal of the dura mater, implantation of a closed cranial window, and intravenous injection of fluorescein, three-dimensional reconstructions of cortical capillaries were performed down to a depth of 250 μm below the pial surface. Using a one-dimensional approach (single line scanning), erythrocyte (negative contrast in fluorescently labelled plasma) and leucocyte (labelled with rhodamine 6 G) velocity and supply rate in cortical capillaries were measured. The effect of CO2-inhalation on capillary blood flow dynamics was studied. Capillaries were imaged continuously for up to 1 h without changes in flow or fluorescence pattern. However, by increasing the laser power 10–100-fold, aggregate formation was induced and capillaries were occluded, possibly due to damage to vascular endothelium. We conclude that CSLM can be used to study morphological and dynamic aspects of fluorescently labelled subsurface structures in organs of experimental animals. 相似文献
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Alexandra C. K?lbl Udo Jeschke Ulrich Andergassen 《International journal of molecular sciences》2016,17(8)
Epithelial to mesenchymal transition (EMT) is a process involved in embryonic development, but it also plays a role in remote metastasis formation in tumor diseases. During this process cells lose their epithelial features and adopt characteristics of mesenchymal cells. Thereby single tumor cells, which dissolve from the primary tumor, are enabled to invade the blood vessels and travel throughout the body as so called “circulating tumor cells” (CTCs). After leaving the blood stream the reverse process of EMT, the mesenchymal to epithelial transition (MET) helps the cells to seed in different tissues, thereby generating the bud of metastasis formation. As metastasis is the main reason for tumor-associated death, CTCs and the EMT process are in the focus of research in recent years. This review summarizes what was already found out about the molecular mechanisms driving EMT, the consequences of EMT for tumor cell detection, and suitable markers for the detection of CTCs which underwent EMT. The research work done in this field could open new roads towards combating cancer. 相似文献