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91.
Behaviour of light metals with PVD-CrN coatings using different test methods The application of thin hard coatings on machining tools, e.g. drilling tools is state of the art. The increase of lifetime of coated Tools compared to uncoated tools is well known. [1]. In this context ?separation of functions”? is an often used phrase, by meaning the separation of functions of the volume and the surface of materials. Going one step forward, from the point of view of tribology or corrosion this means, you have ?only”? to protect the surface by using a ?good”? coating without looking at the material underneath. In the past the influence of substrate materials or the optimization of the system (substrate-coating) was not the main aim of PVD development. Looking at substrate and coating as a system is especially necessary, if the differences of the properties of substrate and coating are large (e.g. hard coating – light metals). This paper shows different aspect of the tribological and electrochemical characterization of PVD coated light metals (CrN coating).  相似文献   
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The cytokine interleukin-6 is consistently detected in the brains of Alzheimer's disease patients but not in the brains of nondemented elderly persons. Until recently it was unclear whether an interleukin-6-associated inflammatory mechanism is an early or late event in the pathological cascade of Alzheimer's disease. We investigated whether interleukin-6 could be detected in plaques of Alzheimer's disease patients prior to the onset of neuritic degeneration. We found interleukin-6 mostly in plaques where neuritic pathology has not yet developed. This indicates that the appearance of interleukin-6 may precede neuritic changes and is not just a consequence of neuritic degeneration. Therefore, one may hypothesize that activation of inflammatory mechanisms may cause neuritic degeneration in plaques. A suppression of interleukin-6 synthesis could, therefore, be of therapeutic value. Upon screening a number of substances, we found that a small number of nonsteroidal antiinflammatory drugs, including tenidap, were able to inhibit interleukin-6 synthesis in cultured human astrocytoma cells. These substances may be therapeutically useful in Alzheimer's disease and should be evaluated in clinical studies.  相似文献   
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Solid state electronic ballasts promise significant energy savings in the lighting systems of large buildings. However, organizational factors and standard operating procedures may inhibit the adoption of this technology in the large, bureaucratic public and private sector organizations which represent the major potential users of this technology.  相似文献   
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117 individuals (mean age 37.77 yrs) who were at the fire and 30 individuals (mean age 40.72 yrs) who were not at the fire (bereaved families and rescue workers) were assessed regarding objective stressfulness of their fire experience, subjective stressfulness, and intensity of psychological symptoms (the Psychiatric Evaluation Form, PEF) in a structured clinical interview approximately 1 yr after the fire. Ss also filled out the Symptom Checklist-90, Revised Version (SCL-90R). 88 Ss were followed-up at 2 yrs. The group as a whole was more impaired than comparison samples of normals but less impaired than outpatients. Ss at the fire were less impaired than those not at the fire, who were similar to outpatients on the PEF. The latter group improved significantly on several measures from 1 to 2 yrs postfire, whereas the group at the fire showed little change. Results are discussed in the context of the specific instruments and methodology used in the present study, impairment levels of other samples, and the nature of the particular disaster. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Attempted to clarify a number of inconsistent and contradictory findings regarding interactions between patient diagnosis (schizophrenic vs. neurotic) and the A-B therapist variable. 37 psychiatric residents completed Kemp's version of the A-B scale. The 10 highest and 10 lowest scorers then rated 4 patient vignettes on likability, discomfort, interest in treating, and prognosis. Patient social class as well as diagnosis were systematically controlled. Results support some of the previous research on likability but provided no support for other A-B * Patient Type interactions. A number of main effects for diagnosis and social class indicate that, in general, residents of both types hold more favorable attitudes toward neurotic and middle-class patients than they do toward schizophrenic and lower-class patients. (23 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
Self-mode-locking of a cross-excited electrically pulsed CO2laser has been observed and studied as a function of cavity length and operating pressure. The best results are obtained at a pressure of 450 torr with cavity lengths on the order of 1m. Two-ns duration pulses have been measured, the shortest pulses observed to date at 10.6-μ wavelength. With longer cavities more axial modes are locked, resulting in a longer dead time between pulses; however, the pulsewidths increase with increasing cavity length. Mode-locking was not improved by the use of the bleachable absorber SF6.  相似文献   
98.
Aufteilung des Schmiedevorgangs in Abkühl- und Umformvorgänge. Wärmebilanzen für den Abkühl- und den Umformvorgang. Numerisches Lösungsverfahren. Auswertungen.  相似文献   
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