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71.
High temperature corrosion tests in 80 pct Na2SO4-20 pct NaCI were made on five Fe-30 wt pct Cr-5 wt pct Al alloys containing various amounts of cerium up to 0.68 pct. After the corrosion tests, samples were examined metallographically and by X-ray diffraction and X-ray microanalysis. It was found that the surface scale formed on each sample decreased in thickness as the Ce content increased. Electron probe microanalyses suggest that this retarding behavior is related to the early formation of a Ce-induced protective scale of α-Al2O3. The role of Ce in promoting the formation of the α-Al2O3 scale is discussed.  相似文献   
72.
73.
The standard Gibbs energies of formation of Fe2Mo3O12, Fe2Mo3O8, FeMoO4, and Fe2MoO4 of the Fe-Mo-O ternary system and the μ phase of the Fe-Mo binary system have been determined by measuring electromotive forces of galvanic cells having an Y2O3-stabilized ZrO2 solid electrolyte. The results are as follows: $$\begin{gathered} \Delta _f G^\circ (FeMoO_4 )/kJ \cdot mol^{ - 1} = - 1053.5 + 0.2983(T/K) \pm 0.4 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_8 )/kJ \cdot mol^{ - 1} = - 2347 + 0.6814(T/K) \pm 1 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_{12} )/kJ \cdot mol^{ - 1} = - 2993 + 0.9105(T/K) \pm 2 \hfill \\ Temperature range: 1040 to 1145 K \hfill \\ \Delta _f G^\circ (Fe_{0.58} Mo_{0.42} )/kJ \cdot mol^{ - 1} = - 18.7 + 0.0117(T/K) \pm 0.1 \hfill \\ Temperature range: 1162 to 1223 K \hfill \\ \Delta _f G^\circ (Fe_2 MoO_4 )/kJ \cdot mol^{ - 1} = - 1174 + 0.342(T/K) \pm 1 \hfill \\ Temperature range: 1243 to 1466 K \hfill \\ \end{gathered} $$ where the standard pressure is 1 bar (100 kPa).  相似文献   
74.
We developed a low cost, user-friendly multimedia delivery system, to provide medical lectures saved as multimedia contents to persons engaged in medicine. This system was created using the RealSystem package with the TCP/IP network. Users can review lectures and medical meeting presentations with video and audio through the Internet, whenever convenient. Each medical source of video and slide has been clearly displayed on a screen. Members of medical associations or medical students can easily review the most interesting parts of these files. This system is being used efficiently in distance learning and aids the diffusion of the latest information and technology to busy physicians and medical students.  相似文献   
75.
A variable-pressure scanning electron microscopy (VP-SEM) with a cooling stage permits long hours of observation of water-containing specimens in their natural or close to natural state, without the conventional specimen preparations of fixation, dehydration, drying and metal coating. It reduces water vaporization and beam damage by keeping the specimens at a low temperature. We observed Bacillus cereus colonies on nutrient agar, which would shrink significantly if any conventional specimen preparation technique were used. We also studied the growing process of the bacteria on raw and steamed rice using the VP-SEM without conventional preparation techniques. Original specimens were directly mounted onto specimen holders and their backscattered electron images observed under the following conditions: specimen stage temperature, -10 degrees C; specimen chamber vacuum level, 30-70 Pa; and accelerating voltage, 15-20 kV. We recognized that the VP-SEM minimized deformation of the colonies due to shrinkage of the nutrient agar, and successfully imaged the morphology of the colonies and bacteria without a decline in bacteria number, which is apt to occur during fixation and dehydration. Also, the growth process of the bacteria on raw or steamed rice could be observed promptly, since there is no specimen preparation step.  相似文献   
76.
A gene encoding chitinase from Aeromonas sp. no. 10S-24 was expressed using pTrc99A in Escherichia coli JM 105 which yielded a 5-fold higher activity than when pUC19 was used. Three different truncated enzymes (SA-1, SA-2 and SA-3) were obtained after purification. Their isoelectric points were 7.0, 6.9, and 6.7, respectively. The enzymes showed two optimum pHs, 4.0 and 7.0, when incubated with ethylene glycol chitin as the substrate, and were stable over a wide pH range (3.0-9.0). The optimum temperature was 60 degrees C and the enzymes were stable up to 50 degrees C. The chitinases exhibited wide substrate specificities for chitin-related compounds.  相似文献   
77.
This paper considers a fault-tolerant decentralized H-infinity control problem for multi-channel linear time-invariant systems. The purpose is to design a decentralized H-infinity output feedback controller to.stabilize the given system and achieve a certain H-infinity performance requirement both in the normal situation and in the situation where any one of the local controllers fails. The designed problem is reduced to a feasibility problem of a set of bilinear matrix inequalities (BMIs). An algorithm is proposed to solve the BMIs. First, the normal situation is considered where all the local controllers are functioning. The local controllers are obtained from a standard centralized H-infinity controller by using a homotopy method imposing a structural constraint progressively. Secondly, the above case is extended to the one where any one of the local controllers fails. We again use a homotopy method where the coefficient matrices of the failed controller are decreased progressively to zero. The efficiency of the proposed algorithm is demonstrated by an example.  相似文献   
78.
Optical tweezers are powerful tools for manipulating single DNA molecules using fluorescence microscopy, particularly in nanotechnology‐based DNA analysis. We previously proposed a manipulation technique using microstructures driven by optical tweezers that allows the handling of single giant DNA molecules of millimetre length that cannot be manipulated by conventional techniques. To further develop this technique, the authors characterised the microstructures quantitatively from the view point of fabrication and efficiency of DNA manipulation under a fluorescence microscope. The success rate and precision of the fabrications were evaluated. The results indicate that the microstructures are obtained in an aqueous solution with a precision ∼50 nm at concentrations in the order of 106 particles/ml. The visibility of these microstructures under a fluorescence microscope was also characterised, along with the elucidation of the fabrication parameters needed to fine tune visibility. Manipulating yeast chromosomal DNA molecules with the microstructures illustrated the relationship between the efficiency of manipulation and the geometrical shape of the microstructure. This report provides the guidelines for designing microstructures used in single DNA molecule analysis based on on‐site DNA manipulation, and is expected to broaden the applications of this technique in the future.Inspec keywords: DNA, molecular biophysics, fluorescence, optical microscopy, radiation pressure, biological techniquesOther keywords: optically driven microstructures, single DNA molecule analysis, fluorescence microscopy, optical tweezers, nanotechnology‐based DNA analysis, manipulation technique, aqueous solution, fine tune visibility, yeast chromosomal DNA molecules, geometrical shape, on‐site DNA manipulation  相似文献   
79.
Recently, composite insulators have been increasingly employed mainly for economic reasons. We have developed a new type of outdoor termination using a composite insulator, which can be installed horizontally on a steel tower in order to reduce the construction cost. In this outdoor termination, SF6 gas is filled in the composite insulator and a cold shrinkable premolded rubber unit is applied instead of the combined use of a rubber‐molded stress relief cone, epoxy resin insulator and spring unit. The application of the composite insulator, SF6 gas and cold shrinkable premolded rubber unit reduces the total weight and makes it possible to install the termination horizontally on the tower. The new‐type outdoor termination for 77‐kV XLPE cable has already been applied in commercial use and enabled a reduction of the construction costs for power transmission lines. A 154‐kV new‐type outdoor termination has been developed and its initial electrical tests were successfully completed. This paper describes the design and performance of both 77‐kV and 154‐kV new‐type outdoor termination, and a follow‐up survey of the 77‐kV new termination in a commercial use. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 18– 26, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20511  相似文献   
80.
The authors have been working on natural language understanding based on the knowledge representation language L md and its application to robot manipulation by verbal suggestion. The most remarkable feature of L md is its capability of formalizing spatiotemporal events in good correspondence with human/robotic sensations and actions, which can lead to integrated computation of sensory, motory and conceptual information. This paper describes briefly the process from text to robot action via semantic representation in L md and the experimental results of robot manipulation driven by verbal suggestion. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
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