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61.
The thermodynamic properties of double oxides in rare earth-transition metal (V and Mn)-oxygen ternary systems have been collected and evaluated to examine their stability using chemical potential diagrams plotted as log (αAB) vs log ( P (O2)). The thermodynamic regularities of perovskites, pyrochlores, and other compounds have been discussed in terms of the effective ionic radii across a series of rare earths. The obtained regularities have been used to estimate tentatively the thermodynamic properties of some rare-earth vanadium and manganese oxides.  相似文献   
62.
A new milling technique based on a focused ion beam (FIB) microsampling system is proposed to avoid the curtaining effect, commonly occurring in other FIB milling methods, in order to obtain a crosssectional device specimen with uniform thickness can be obtained for electron holographic observation.  相似文献   
63.
A giant Seebeck coefficient of ?890 μV/K at 500 °C has been observed in Y0.2Sr0.8TiO3 prepared using nanocubes. Doping rare earth elements, RE, has revealed that small RE is effective to enhance the Seebeck coefficient. Through soft mode observations by Raman spectroscopy and structural calculations based on density functional theory, it has been found that the breakdown of inversion symmetry of the perovskite structure near the surface of nanocubes can be recovered by doping with small RE. Because the dielectric constant is strongly related to the surface structure in this compound, we suggest that RE doping modulates the potential barrier at the grain boundary, resulting in a pronounced energy filtering effect in Y doped SrTiO3.  相似文献   
64.
Fructosyl amino acid oxidase (FAOD) is the enzyme catalyzing the oxidative deglycation of Amadori compounds, such as fructosyl amino acids, yielding the corresponding amino acids, glucosone, and H(2)O(2). In a previous report, we determined the primary structures of cDNAs coding for FAODs from two fungal strains Aspergillus terreus AP1 and Penicillium janthinellum and we found that both fungal FAODs included the putative peroxisome targeting signal 1 (PTS1) at the carboxyl terminal (Yoshida, N. et al., Eur. J. Biochem., 242, 499-505, 1996). In this study, we determined the intracellular localization of FAODs in these two fungi. Subcellular fractionation experiments and immuno-electronmicroscopic observations, together with the previous findings indicated that the FAODs were localized in peroxisomes of A. terreus AP1 and P. janthinellum. These FAODs were also found to belong to a new member of "peroxisomal sarcosine oxidase family protein" in eucaryotic cells.  相似文献   
65.
Acetate ester synthesis was studied in vitro with the ethyl acetate-producing yeast Candida utilis. The level of enzyme activity observed for the NAD+-dependent hemiacetal dehydrogenase acting on hemiacetal, which was produced non-enzymatically from an alcohol and an aldehyde, was much greater than that for the other enzyme involved in ester synthesis, alcohol acetyltransferase. The level of ethyl acetate synthesis in vivo approximately paralleled the hemiacetal dehydrogenase (HADH) activity. The results suggest that the main pathway for ethyl acetate synthesis in C. utilis involves a novel hemiacetal dehydrogenase activity.  相似文献   
66.
A 0.3-μm sub-10-ns ECL 4-Mb BiCMOS DRAM design is described. The results obtained are: (1) a Vcc connection limiter with a BiCMOS output circuit is chosen due to ease of design, excellent device reliability and layout area; (2) a mostly CMOS periphery with a specific bipolar use provides better performances at high speed and low power; (3) the direct sensing scheme of a single-stage MOS preamplifier combined with a bipolar main amplifier offers high speed; and (4) the strict control of MOS transistor parameters has been proven to be more important in obtaining high speed DRAMs, based on the 4-Mb design  相似文献   
67.
Single-atom (SA) catalysts exhibit high activity in various reactions because there are no inactive internal atoms. Accordingly, SA cocatalysts are also an active research fields regarding photocatalytic hydrogen (H2) evolution which can be generated by abundant water and sunlight. Herein, it is investigated whether 10 transition metal elements can work as an SA on graphitic carbon nitride (g-C3N4; i.e., gCN), a promising visible-light-driven photocatalyst. A method is established to prepare SA-loaded gCN at high loadings (weight of ≈3 wt.% for Cu, Ni, Pd, Pt, Rh, and Ru) by modulating the photoreduction power. Regarding Au and Ag, SAs are formed with difficulty without aggregation because of the low binding energy between gCN and the SA. An evaluation of the photocatalytic H2-evolution activity of the prepared metal SA-loaded gCN reveals that Pd, Pt, and Rh SA-loaded gCN exhibits relatively high H2-evolution efficiency per SA. Transient absorption spectroscopy and electrochemical measurements reveal the following: i) Pd SA-loaded gCN exhibits a particularly suitable electronic structure for proton adsorption and ii) therefore they exhibit the highest H2-evolution efficiency per SA than other metal SA-loaded gCN. Finally, the 8.6 times higher H2-evolution rate per active site of Pd SA is achieved than that of Pd-nanoparticles cocatalyst.  相似文献   
68.
"WEEE"和"RoHS"指令的对应策略   总被引:3,自引:0,他引:3  
随着“WEEE”和“RoHS”指令实施的日益临近,国内许多企业苦于进展缓慢。本文提出了企业的对应策略。  相似文献   
69.
We have proposed a method for diagnosing analog circuits that is realized by combining the operation-region model and the XY zoning method. In the method, we could implement a diagnosis procedure based on a diagnostic method for digital circuits because we developed a data processing method to handle data discretely. In this paper, we improve the method by using an adaptive test to obtain a shorter diagnostic sequence length and show its characteristics. Moreover, we propose a new data processing method that utilizes the output response of a circuit to obtain better diagnostic performance. We demonstrate the effectiveness of the proposed methods by applying them to ITC’97 benchmark circuits with hard faults and soft faults. These improved methods can reduce the diagnostic sequence length without degrading the performance of diagnostic resolution and CPU time.  相似文献   
70.

A high-speed wireline interfaces, e.g. LVDS (Low Voltage Differential Signaling), are widely used in the aerospace field for powerful computing in artificial satellites and aircraft [19]. This paper describes Bit Error Rate (BER) prediction methodology for wireline data transmission under irradiation environment at the design stage of data transmitter, which is useful in proactively determining if the design circuit meets the BER criteria of the target system. Using a custom-designed LVDS transmitter (TX) to enhance latch-up immunity [42], the relationship between transistor size and BER has been analyzed with focusing on Single Event Effect (SEE) as a cause of the bit error. The measurement was executed under 84Kr17+ exposure of 322.0 MeV at various flux condition from 1?×?103 to 5?×?105 count/cm2/sec using cyclotron facility. For the analysis of the bit error, circuit simulation by SPICE was utilized with expressing the irradiation environment by a current source model. The current source model represents a single event strike into the circuit at drain and substrate junctions in bulk MOSFETs. For the construction of the current source model, a charge collection was simulated at the single particle strike with the creation of 3D Technology CAD (TCAD) models for the MOS devices of bulk transistor process technology. The simulation result of the charge correction was converted to a simple time-domain equation, and the single-event current source model was produced using the equation. The single-event current source was applied to SPICE simulation at bias current related circuits in the LVDS transmitter, then simulation results are carefully verified whether the output data is disturbed enough to cause bit errors on wireline data transmission. By the simulation, sensitive MOSFETs have been specified and a sum of the gate area for these MOSFETs has 29% better correlation than the normal evaluation index (sum of the drain area) by comparison to the actual BER measurement. Through the precise revelation of the sensitive area by SPICE simulation using the current model, it became possible to estimate BER under irradiation environment at the pre-fabrication design stage.

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