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881.
882.
In this study, an air window collector having vertical black blinds was investigated experimentally under actual outdoor conditions. The vertical blind was installed between two 120 × 80 cm glass panes. It can rotate about the vertical axis. The fully open position makes a 90° angle with the vertical plane. A commercially available blind made of cloth and coated with black paint was tested. The air circulation in the system is provided by a fan parallel to blinds. Various parameters were measured and recorded using a data acquisition system. The effect of these parameters on the thermal performance of the system were determined experimentally. 相似文献
883.
Y. Liu W. Zhu O. K. Tan X. Yao Y. Shen 《Journal of Materials Science: Materials in Electronics》1996,7(4):279-282
A low-temperature plasma-enhanced chemical vapour deposition (PECVD) technique has been employed to produce ultrafine tin oxide powders. The structural features and phase transition of this material have been characterized using differential thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction, infrared spectroscopy (IR) and transmission electron microscopy (TEM). The oxygen absorption behaviour and gassensing properties have been investigated by electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS) and electrical measurements. Thick film gas sensors made from such ultrafine SnO2 powders yield better sensitivities than those of normal undoped SnO2 gas sensors. A gas-sensing reaction mechanism is also proposed. 相似文献
884.
885.
886.
A 63-year-old man developed paraparesis and signs of meningeal irritation 4 days after a fall which caused a minor contusion of the cervical spine. Magnetic resonance imaging (MRI) revealed an extensive spinal subdural hematoma. The usefulness of MRI for diagnosis and successful conservative treatment is discussed. 相似文献
887.
Sjolund O. Louderback D.A. Hegblom E.R. Ko J. Coldren L.A. 《Electronics letters》1998,34(18):1742-1743
Monolithic integration of high performance microlensed resonant photodetectors and vertical cavity lasers (VCLs) from a single epitaxial growth is presented. The VCLs have sub-200 μA threshold currents. Adjacent detectors have the same operating wavelength and responsivities of ~0.4 A/W with ~6 nm optical bandwidths 相似文献
888.
T. B. Arbuzova A. I. Khlystov V. O. Nikitin 《Refractories and Industrial Ceramics》1994,35(7):234-235
The problem of the electrical conductivity of heat-resistant concretes and bonding agents is considered and a method for determining
this parameter is suggested. In addition to the thermal resistivity, the electric conductivity is a factor affecting the lifetime
of lining materials for high-temperature devices. The problem is especially urgent in electric heaters.
Translated from Ogneupory, No. 7, pp. 25–26, July, 1994. 相似文献
889.
The experience of reprocessing of dusty wastes in centrifugal plasma plants is described. Theoretical calculations by means of a mathematical model are given.Translated from Ogneupory, No. 3, pp. 16–17, March, 1994. 相似文献
890.
Trimethylpentane diol (TMPD) dibenzoate use in vinyl as a plasticizer is not well recognized, and little has been published on vinyl performance characteristics. To assess new applications for vinyl, a basic evaluation was conducted. Based on the results of the screen and other considerations an evaluation for utility in plastisol silk screen ink was conducted. The results indicated that the TMPD dibenzoate performed very well in white ink, requiring good fabric dye bleed resistance compared to polymeric and phthalates currently being used for non-bleed ink. Non-bleed characteristics are important for colored tee shirt printing. The benzoate is a good solvator and has excellent extraction resistance. 相似文献