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81.
Generation of Technology-Independent Retargetable Analog Blocks 总被引:1,自引:0,他引:1
R. Castro-López F. V. Fernández F. Medeiro A. Rodríguez-Vázquez 《Analog Integrated Circuits and Signal Processing》2002,33(2):157-170
This paper introduces a complete methodology for retargeting of analog cells to different sets of specifications. This methodology is technology-independent, thus allowing the migration, from one technology to another, of the circuit under retargeting. Careful integration of the device sizing and layout generation tasks via the incorporation of layout constraints during the sizing process allows to generate fully functional designs in a few minutes. The methodology is illustrated via the retargeting of a fully-differential Miller-compensated two-stage operational amplifier for a new set of specifications and two different technological processes.An erratum to this article can be found at 相似文献
82.
TeMxMo1.7O mixed oxides (M = V and/or Nb; x = 0-1.7) have been prepared by calcination of the corresponding salts at 600 °C in an atmosphere of N2. A new crystalline phase, with a Te/V/Mo atomic ratio of 1/0.2-1.5/1.7, has been isolated and characterised by XRD and IR spectroscopy. This phase is observed in the TeVMo or TeVNbMo mixed oxide but not in the TeNbMo mixed oxide. The new crystalline phase shows an XRD pattern similar to Sb4Mo10O31 and probably corresponds to the M1 phase recently proposed by Aouine et al. (Chem. Commun. 1180, 2001) to be present in the active and selective MoVTeNbO catalysts. Although these catalysts present a very low activity in the propane oxidation, they are active and selective in the oxidation of propene to acrolein and/or acrylic acid. However, the product distribution depends on the catalyst composition. Acrolein or acrylic acid can be selectively obtained from propene on Nb-free or Nb-containing TeVMo catalysts, respectively. The presence of both V and Nb, in addition to Mo and Te, appears to be important in the formation of acrylic acid from propene. 相似文献
83.
Kunkel Mark A.; Hector Mark A.; Góngora Coronado Elías; Castillo Vales Victor 《Canadian Metallurgical Quarterly》1989,36(3):322
Conducted a study of client expectations of psychological services in Yucatán, Mexico, under the sponsorship of a grant from the Organization of American States. The Expectations about Counseling–Brief form (EAC-B) questionnaire was translated and administered to 488 subjects across age, sex, and experience with psychological services. Subsequent analyses supported the reliability and robustness of the Spanish EAC-B, with factor structure similar to the EAC-B in English. Some relation was found among age, sex, prior counseling experience, and expectations about counseling. Implications of these data for future research and comparison with U.S. subjects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Summary The mass spectra of secondary ions emitted from PVK thin layers under 2 keV Xe+ bombardment were measured. The charasteristic elemental and molecular ions emitted were specified. The temperature dependence of the secondary emission was also measured. The results obtained were briefly discussed in terms of the ion beam-induced polymer structure fragmentation.Work supported by the research programme MR-I-5-8. 相似文献
85.
The comfort diagrams and the so-called PMV-PPD values are already used today directly and indirectly in a wide field in technical practice, even at a standard level. This theory is known also in Hungary, and the PMV-PPD values have been used by us for the solution of a design problem. The task was to elaborate a calculation method, an index number suitable for the determination of the thermal confort effect in the case of occasional underheating of residential and communal buildings in winter.The results of this work are presented in this paper. 相似文献
86.
87.
Summary Electropolymerization of o-(CH3O)2C6H4 (Veratrole) in dry acetonitrile/tetrabutylammonium tetrafluoroborate at platinum electrode, yields a green polymeric conducting solid. As the pressure is increased, the material becomes more conductive, but sharp changes towards lower conductivity occur at 4.2 and 6.2 metric tons pressure, probably due to phase transitions. The photoconductivity shows an exponential increase as temperature is increased, but it shows reversible changes at 200 K, 225 K and 250 K during slow warming, also attributable to phase transitions. Photoconductivity of Polyveratrole increases with the radiation frequency, being higher under blue light than under red of infrared radiation and there is a linear increase of photoconductivity with radiation density. Conductivity transients show that the conductivity increases exponentially with time to the saturation point within few minutes, and it also decreases exponentially when the light is turned off and the circuit is open. This behaviour can be explained by formation and encounter of electron and hole as current carriers. A preliminary study indicates a piezoelectric effect for the material. absorption spectroscopy allowed the measurements of the material band gap. 相似文献
88.
BBN (BaBi2Nb2O9) is very interesting and promising lead free material with relaxor properties in capacitors, sensors and actuators. 相似文献
89.
90.
Ricardo Beristain‐Cardoso Anne‐Claire Texier Reyes Sierra‐Álvarez Jim A Field Elías Razo‐Flores Jorge Gómez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1197-1203
BACKGROUND: Simultaneous removal of sulfur, nitrogen and carbon compounds from wastewaters is a commercially important biological process. The objective was to evaluate the influence of the CH3COO?/NO3? molar ratio on the sulfide oxidation process using an inverse fluidized bed reactor (IFBR). RESULTS: Three molar ratios of CH3COO?/NO3? (0.85, 0.72 and 0.62) with a constant S2?/NO3? molar ratio of 0.13 were evaluated. At a CH3COO?/NO3? molar ratio of 0.85, the nitrate, acetate and sulfide removal efficiencies were approximately 100%. The N2 yield (g N2 g?1 NO3?‐N consumed) was 0.81. Acetate was mineralized, resulting in a yield of 0.65 g inorganic‐C g?1 CH3COO?‐C consumed. Sulfide was partially oxidized to S0, and 71% of the S2? consumed was recovered as elemental sulfur by a settler installed in the IFBR. At a CH3COO?/NO3? molar ratio of 0.72, the efficiencies of nitrate, acetate and sulfide consumption were of 100%, with N2 and inorganic‐C yields of 0.84 and 0.69, respectively. The sulfide was recovered as sulfate instead of S0, with a yield of 0.92 g SO42?‐S g?1 S2? consumed. CONCLUSIONS: The CH3COO?/NO3? molar ratio was shown to be an important parameter that can be used to control the fate of sulfide oxidation to either S0 or sulfate. In this study, the potential of denitrification for the simultaneous removal of organic matter, sulfide and nitrate from wastewaters was demonstrated, obtaining CO2, S0 and N2 as the major end products. Copyright © 2008 Society of Chemical Industry 相似文献