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991.
Schwerdt M. Brautigam B. Bachmann M. Doring B. Schrank D. Hueso Gonzalez J. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):677-689
992.
We present a model that can predict the Seebeck coefficient of different interfaces. Within this model we solve the Poisson equation and Schrödinger equation self-consistently to obtain the potential profile across the interface. Then we use the nonequilibrium Green’s function (NEGF) method to calculate the transport properties across the interface. We apply our model to a ZnO grain boundary, describing the boundary as a back-to-back Schottky barrier. The potential profile in the considered system is similar to a rigid-shift potential, and thus the Seebeck coefficient obtained from the rigid-shift potential shows no deviation in comparison with the Seebeck coefficient obtained from the self-consistent potential. 相似文献
993.
Brenner T. Hunziker W. Smit M. Bachmann M. Guekos G. Melchior H. 《Electronics letters》1992,28(22):2040-2041
The authors have realised vertically tapered and antireflection-coated waveguides in InP/InGaAsP with 1.7 dB coupling loss and relaxed alignment tolerances to lensed single-mode fibres with spot diameters of 3.8 mu m. The waveguide tapers are fabricated by a dip-etch process that is well suited for integration with optical waveguide circuits.<> 相似文献
994.
995.
Andriy Zolotaryov Silvana Goetze Julien Bachmann Detlef Goerlitz Dietrich Hesse Kornelius Nielsch 《Advanced Engineering Materials》2011,13(4):330-335
We have studied thermal solid‐state reactions in the Fe2O3/CoXOY/ZnO thin film systems grown using the atomic layer deposition technique. The compound produced after annealing at 700 °C is found to be a complex mixture of three different spinel phases: ZnCo2O4, CoFe2O4, and ZnFe2O4. The magnetic properties of the compound strongly depend on the atomic ratio of Fe3+ and Co2+ atoms, which can be set by choosing the corresponding thicknesses of the Fe2O3 and CoXOY films. In addition, we also find a formation of 100 nm voids at the interface between Fe–Co–Zn–O compound and remaining ZnO film after 1h annealing at 700 °C in argon atmosphere. The formation of these voids shows indirectly the preferential outward diffusion of Zn2+ ions from ZnO into the Fe2CoO4 phase layer what we prove via our magnetic measurements. 相似文献
996.
997.
LM Roth 《Canadian Metallurgical Quarterly》1989,40(8):5617-5623
998.
M Shipkova PD Niedmann VW Armstrong E Schütz E Wieland LM Shaw M Oellerich 《Canadian Metallurgical Quarterly》1998,44(7):1481-1488
We describe a reversed-phase HPLC method for determination of total mycophenolic acid (MPA), its free concentration (MPAf), and the glucuronide metabolite (MPAG), based on simple sample preparation and gradient elution chromatography. The compounds were quantified in parallel by absorbance at 254 nm and 215 nm in the internal standard mode. Linearity was verified up to 50 mg/L for MPA and up to 500 mg/L for MPAG (r >0.999). Detection limits at 215 and 254 nm were, respectively, 0.01 and 0.03 mg/L for MPA, and 0.03 and 0.1 mg/L for MPAG. The recovery of MPA was 95-106%; recovery of MPAG was 96-106%. The imprecision (CV) for MPA (0.2-25 mg/L) was <8.4% (254 nm) and <4.4% (215 nm) within day (n = 12) and <9.2% (254 nm) and <6.2% (215 nm) between days (n = 12). The imprecision for MPAG (10-250 mg/L) was <4.9% (254 nm) and <3.4% (215 nm) within day, and <6.1% (254 nm) and <5.9% (215 nm) between days. For quantification of MPAf, 100 microL of ultrafiltrate was applied directly to the column. The detection limit was 0.005 mg/L at 215 nm and 0.015 mg/L at 254 nm. In the range between 18-210 microg/L, the within-day CVs were <11.8% (n = 12) and the between-day CVs were <15.8% (n = 12). 相似文献
999.
The effects of microinjection of a NO synthase inhibitor--N-nitro-L-arginine (L-NNA) and NO donor-sodium nitroprusside (SNP) into ventrolateral medulla on blood pressure (BP), heart rate (HR) and renal sympathetic nerve activity (RSNA) were examined in anesthetized rats to define the role of L-arginine: NO pathway in the central regulation of BP and to explore the underlying mechanism. The results obtained were as follows: (1) Following microinjection of L-NNA into rostral ventrolateral medulla (RVLM), both of MAP and RSNA were increased. The effects lasted for more than 30 min and could be reversed by prior intravenous injection of L-arginine. (2) In response to microinjection of SNP into RVLM, MAP and RSNA were decreased, while HR showed no significant change. (3) During microinjection of L-NNA into caudal ventrolateral medulla (CVLM), MAP, HR and RSNA were decreased. (4) Upon injection of SNP into CVLM, MAP and RSNA were increased, but HR showed no significant change. The above-mentioned results indicate that the L-arginine: NO pathway may exhibit a modulatory action on the activity of ventrolateral medulla neurons. 相似文献
1000.
MD Holmes CB Dodrill RJ Wilkus LM Ojemann GA Ojemann 《Canadian Metallurgical Quarterly》1998,39(11):1189-1193
PURPOSE: This study was undertaken to determine what changes, if any, occur in the electroencephalogram (EEG) and in neuropsychological test findings of adults with medically intractable complex partial epilepsy over a 10-year period. METHODS: We studied 35 adults, with a mean age of 32 years (range, 16-59 years) at time of initial testing. We compared the distribution of epileptiform patterns documented on the initial pair of waking and sleeping EEGs to those observed on another pair obtained 10 years later. During this same 10-year period, we also examined changes in the Wechsler Adult Intelligence Scale (WAIS) and on the tests from the Neuropsychological Battery for Epilepsy. RESULTS: The EEGs of 28 (80%) of patients at the tenth year were identical to those seen initially. Five (14%) of patients demonstrated EEGs after 10 years with either no discharges or only unilateral discharges, where bilateral discharges were seen a decade earlier. Only two (6%) of patients had EEGs at the tenth year that showed bilateral discharges where only unilateral discharges were seen originally. We found no general change in intelligence or neuropsychological functioning after 10 years, although a few subtle losses were noted on several neuropsychological measures. CONCLUSIONS: For most adults with medically intractable complex partial epilepsy, the EEG and neuropsychological test scores remain reasonably stable over a decade. 相似文献