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951.
952.
Thick film technology was used to manufacture a solid-state electrochemical nitrogen dioxide sensor. The prepared sensor
has a linear dependence of electromotive force that is based in the NO2 concentration level. This paper presents discussion on a thick-film sensor that has a much smaller dimension and shorter
response time as compared to typical ceramic solid-state electrochemical devices.
Received: 26 February 1996/Accepted: 27 June 1996 相似文献
953.
954.
G Kadushin 《Canadian Metallurgical Quarterly》1996,23(1):1-21
During parasitization of Heliothis virescens, Campoletis sonorensis deposits an egg along with venom, polydnavirus particles (CsPDV), and ovarian proteins (OPs). Oviposited eggs are not encapsulated, while washed eggs are encapsulated rapidly by H. virescens. Early protection from encapsulation is afforded by a group of 29-36 kD OP glycoforms. These glycoforms are endocytosed by host hemocytes within 30 min post-parasitization (pp) and disrupt hemocyte spreading behavior and egg encapsulation through at least 24 h p.i. Purified CsPDV does not protect eggs from encapsulation early, but disrupts hemocyte spreading and egg encapsulation from 24 h through at least 5 days p.i. Functional activity of CsPDV appears to be correlated with time-dependent accumulation of virus-specific proteins in parasitized insects. We propose that the fast-acting 29-36 kD OP protects Campoletis eggs from encapsulation until accumulation of CsPDV proteins which sustain immunosuppression. 相似文献
955.
956.
R. A. Farrar Z. Zhang S. R. Bannister G. S. Barritte 《Journal of Materials Science》1993,28(5):1385-1390
The influence of prior austenite grain size on the transformation behaviour and microstructural development of C-Mn-Ni weld metals was investigated. It was found that increasing the grain size depressed the start temperature of grain-boundary ferrite and slightly increased the acicular ferrite start temperature. The microstructural products also changed from a boundary-dominated effect in the small grain sizes, to an intragranular-dominated effect in the large grain sizes, and at the same time, the morphology of the acicular ferrite was seen to change to a larger aspect ratio. 相似文献
957.
Übersicht Die folgende Arbeit verfolgt u. a. auch didaktische Absichten. Das Biot-Savartsche Gesetz wird oft falsch oder mindestens sehr mißverständlich dargestellt und auch auf unzulässige Weise benutzt. Ausgangspunkt der Mißverständnisse ist die auch in vielen Lehrbüchern anzutreffende unkorrekte Aussage, man könne einem von StromI durchflossenen Linienelement ds ein magnetostatisches Feld dB [entsprechend der Gleichung (32) des folgenden Beitrags] zuordnen. Im folgenden werden derartige Aussagen untersucht und in modifizierter Form korrekt dargestellt.
Remarks concerning the Law of Biot-Savart
Contents The following paper is at least partly of a didactic nature. The Biot-Savart law of magnetostatics is often interpreted in an illegitimate manner and consequently applied incorrectly. The source of these misunderstandings and errors is the incorrect statement that a magnetic field dB [as given by equation (32) of this paper] is caused by an electric currentI flowing along a line element ds, a statement very popular also in many textbooks. Questions related to this problem are investigated and widespread misleading statements are replaced by correct ones.相似文献
958.
959.
960.
The direct electrooxidation of methanol in acid medium was studied on electrodes made of a perfluorinated membrane with small amounts of metal catalysts incorporated by chemical reduction. Platinum is a good electrocatalyst for this reaction, but needs to be modified by other metals in order to obtain oxidation potentials much more compatible with a working anode in a direct methanol fuel cell. Ruthenium and tin appear to give encouraging results, leading to a negative shift of more than 250 mV as compared to the potential obtained with pure platinum. Other parameters were investigated in this work, such as the working temperature, and the manner of introduction of the methanol into the cell. By gaseous supply, it was possible to carry out measurements at higher temperatures than with methanol in solution, and consequently to greatly improve the performance of the catalytic electrode. 相似文献