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111.
The catalysts of CeO2 and the mixture of CeO2 and CuO were prepared, and the activities of these catalysts for completely oxidizing benzene were studied.The results show that the optimal proportion of CeO2/CuO is 6: 4.The highest temperature at which benzene was completely oxidized on these catalysts at different airspeed was measured.Compared these catalysts with the noble metal used, our catalysts had superiority in the resources and the industrial cost besides good activities. 相似文献
112.
Rajoo R. Lim S.S. Wong E.H. Hnin W.Y. Seah S.K.W. Tay A.A.O. Iyer M. Tummala R.R. 《Advanced Packaging, IEEE Transactions on》2008,31(2):377-385
A wafer level packaging technique has been developed with an inherent advantage of good solder joint co-planarity suitable for wafer level testing. A suitable weak metallization scheme has also been established for the detachment process. During the fabrication process, the compliancy of the solder joint is enhanced through stretching to achieve a small shape factor. Thermal cycling reliability of these hourglass-shaped, stretch solder interconnections has been found to be considerably better than that of the conventional spherical-shaped solder bumps. 相似文献
113.
马勇 《金属材料与冶金工程》2003,31(1):21-24
通过煤种,入窑球冷态强度和还原过程强度,以及钛精矿与煤灰混合物的软化温度等分析探讨了钛精矿预热球团回转窑直接还原产生结圈的可能性,获得了可以避免结圈的结论。 相似文献
114.
115.
K. Fujii J. Fujimoto H. Hayashii R. Kajikawa Y. Masatani H. Ozaki A. Sugiyama R. Suzaki S. Suzuki T.Y. Tsukamoto T.F. Tsukamoto S. Uno S. Iwata 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,236(1):55-63
We constructed and tested a prototype gas sampling electromagnetic calorimeter of the Pb-proportional tube sandwich type. The calorimeter uses conductive plastic tubes and cathode pad readout with a tower structure which resulted in reasonable energy and spatial resolutions for electrons in the momentum range 0.5–4.0 GeV/c; /c). This paper describes the test and the performance studied under various conditions. 相似文献
116.
Grain refinement of Al-7Si alloys and the efficiency assessment by recognition of cooling curves 总被引:5,自引:0,他引:5
Under sand cup solidification condition, the influence of Ti, B concentration, and holding time on the grain size of a high-purity
Al-7Si alloy has been systematically studied. It is found that the grain size decreases rapidly at lower Ti or B additions,
and is almost constant at the higher concentrations. For Al-3B refined Al-7Si alloys, the grain size increases at the initial
period of holding time, and then rapidly becomes independent of holding time; while for Al-7Si alloys refined with Al-5Ti-1B,
the grain size increases with holding time throughout. To evaluate the refinement efficiency, a new method named “intelligent
evaluating of melt quality by pattern recognition of thermal analysis cooling curves” has also been introduced in this article.
The results show that comparing the cooling curve of the evaluated melt with those in a database to find the most similar
one to it can precisely assess the grain refinement efficiency of the measured Al-7Si alloy. In addition, the influence of
Ti, B addition levels, and pouring temperatures on some characteristic parameters of cooling curve has also been discussed. 相似文献
117.
118.
Perturbation analysis and control of two-class stochastic fluid models for communication networks 总被引:2,自引:0,他引:2
Cassandras C.G. Gang Sun Panayiotou C.G. Wardi Y. 《Automatic Control, IEEE Transactions on》2003,48(5):770-782
This paper uses stochastic fluid models (SFMs) for the control and optimization (rather than performance analysis) of communication network nodes processing two classes of traffic: one is uncontrolled and the other is subject to threshold-based buffer control. We derive gradient estimators for packet loss and workload related performance metrics with respect to threshold parameters. These estimators are shown to be unbiased and directly observable from a sample path without any knowledge of underlying stochastic characteristics of the traffic processes. This renders them computable in online environments and easily implementable for network management and control. We further demonstrate their use in buffer control problems where our SFM-based estimators are evaluated based on data from an actual system. 相似文献
119.
The biological decolorization of two industrial, spent textile reactive dyebaths was investigated using a suspended-growth, halophilic mixed culture fed with glucose. Dyebath I contained mainly Reactive Blue 19 (RB19), an anthraquinone dye, whereas dyebath II contained mainly Reactive Blue 21 (RB21), a phthalocyanine dye. Batch assays under anaerobic conditions with the two neutralized dyebaths resulted in 87 and 37% extent of decolorization for dyebaths I and II, respectively. The rate of glucose utilization and the extent of acetate production were impacted in the presence of each dyebath as compared to the control culture. However, dyebath decolorization occurred despite moderate culture inhibition. Reuse of a biologically renovated RB19-containing dyebath in the dyeing process resulted in reproducible but not identical cotton fabric shades as compared to a standard dyeing (i.e., control) using fresh water. This difference is attributed to a variable degree of RB19 aggregation during the dyeing process and is not related to the efficiency of the biodecolorization process. Further improvement of the redyeing efficiency will lead to the development of an in-plant, closed-loop decolorization system resulting in significant water conservation and minimization of textile pollutants such as salt and dyes. 相似文献
120.
A temperature sensor using a fiber-optic Fabry-Perot interferometer is described. A pseudo-heterodyne detection scheme is adopted to read the light phase difference in the Fabry-Perot interference output. A higher harmonic components comparison method is used to stabilize the system and to increase detection linearity. This system realizes not only highly sensitive temperature sensing with good linearity and minimal adjusting error, but also application to the sensing of other physical quantities such as vibrations. Additionally, the signal-to-noise ratio and distortion of the detected signal are investigated as functions of fiber end reflectivity. These results will be useful in designing a high performance fiber-optic Fabry-Perot thermometer. 相似文献