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81.
A simple, rapid, and precise reversed-phase liquid chromatographic method has been developed for the simultaneous determination of metformin in combination with glimepride. Under the developed conditions, good separation of the analytes was achieved in short analysis time. Several parameters affecting the separation of the analytes were studied, including pH and the concentration of SDS. The method is validated and shown to be linear in the range of 25 microg/mL to 150 microg/mL for metformin and 0.1 microg/mL to 0.6 microg/mL for glimepride. The method is applied for the analysis of these analytes in commercially available tablets. 相似文献
82.
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84.
Sergey N. Yurkov Tigran T. Mnatsakanov Michael E. Levinshtein Pavel A. Ivanov Anant K. Agarwal John W. Palmour 《Solid-state electronics》2005,49(12):2011-2015
The switching of high-voltage (1.5 kV) 4H–SiC gate turn-off thyristors (GTOs) by the dV/dt effect has been studied in the temperature range from 300 to 504 K. At a 30 ns rise time of the forward bias V(t), the characteristic bias at which the structure under investigation can be switched on by the dV/dt effect decreases steadily from 289 V at room temperature (dV/dt 9.7 kV/μs) to 137 V at T = 504 K. The characteristic critical charge per unit area, Qcr, equal to 1.9 × 10−7 C/cm2 at room temperature, also decreases steadily as the temperature increases. The main physical mechanisms that contribute to Qcr formation and the temperature dependence of the critical charge are qualitatively analyzed. The influence exerted by two-dimensional processes on the dV/dt switching is examined by making analytical estimates and using a computer simulation. The results obtained agree well with experimental data. 相似文献
85.
The Effects of Implant Activation Anneal on the Effective Inversion Layer Mobility of 4H-SiC MOSFETs
In this paper, we investigate the effective inversion layer mobility of lateral 4H-SiC metal oxide semiconductor field-effect
transistors (MOSFETs). Initially, lateral n-channel MOSFETs were fabricated with three process splits to investigate phosphorus implant activation anneal temperatures
of 1200, 1650, and 1800°C. Mobility results were similar for all three temperatures (using a graphite cap at 1650°C and 1800°C).
A subsequent experiment was performed to determine the effect of p-type epi-regrowth on the highly doped p-well surface. The negative effects of the high p-well doping are still seen with 1500 ? p-type regrowth, while growing 0.5 μm or more appears to be sufficient to grow out of the damaged area. A continuing series of tests are being conducted at present. 相似文献
86.
Luca Testa Hervé Lapuyade Yann Deval Jean-Louis Carbonero Jean-Baptiste Bégueret 《Journal of Electronic Testing》2010,26(3):355-365
A complete study of the fault coverage achievable on two Radio Frequency (RF) Voltage Controlled Oscillators (VCO) is carried
out. The peak-to-peak output voltage detection grants the maximal catastrophic and parametric fault coverage. The VCOs and
the BIST (Built-In Self-Test) circuitry are designed using the STM CMOS 65 nm process. The frequency of oscillation is 3.6 GHz
and the phase noise obtained at 1 MHz offset from the carrier is of −121.7 dBc/Hz for VCO1 and of −118.8 dBc/Hz for VCO2.
The performances of the VCOs are simulated before and after the insertion of the circuitry for the BIST, in order to confirm
the transparency of the BIST. 相似文献
87.
Lin Cheng Anant K. Agarwal Sarit Dhar Sei-Hyung Ryu John W. Palmour 《Journal of Electronic Materials》2012,41(5):910-914
Silicon carbide (4H-SiC) power metal–oxide–semiconductor field-effect transistors (MOSFETs) have been attracting tremendous
attention for high-power applications at a wide range of operating temperatures, owing to their normally-off characteristics,
high-speed switching operation, avalanche capability, and low on-resistance. To optimize performance of 4H-SiC MOSFETs for
various applications at different temperatures, it is important to understand the mechanisms of temperature dependence of
the key parameters, such as on-resistance, threshold voltage, and metal–oxide–semiconductor (MOS) channel mobility. We report
on the temperature dependence of the on-resistance of 20 A, 1200 V 4H-SiC power MOSFETs for temperatures ranging from −187°C
to 300°C. The MOSFET showed normally-off characteristics throughout the entire experimental temperature range. Different temperature
dependences of the total on-resistance in different temperature regimes have been observed. Due to the poor MOS channel mobility
and the low free carrier concentration in the inversion channel of the 4H-SiC MOSFET, the MOS channel resistance is the dominant
part of the total on-resistance. This was also found to be true in a 4H-SiC long-channel lateral MOSFET. 相似文献
88.
Rai SB Singh AK Singh SK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(14):3221-3226
Spectroscopic properties of Ho3+ doped tellurite glass (1 mol.% of Ho3+) have been studied. The absorption and fluorescence spectra have been recorded and analysed using the Judd-Offelt theory. The analysis indicates that Ho doped tellurite glasses can show lasing on the 5F4 (5S2)-5I8 transition (548.0 nm). 相似文献
89.
Santana MD García-Bueno R García G Sánchez G García J Kapdi AR Naik M Pednekar S Pérez J García L Pérez E Serrano JL 《Dalton transactions (Cambridge, England : 2003)》2012,41(13):3832-3842
The synthesis of mono- and dinuclear cyclometallated palladium(II) complexes with deprotonated saccharinate ligands displaying different coordination modes is described. The new compounds were prepared by direct reaction between saccharine and the corresponding hydroxo-complexes [{Pd(μ-OH)(C^N)}(2)] (C^N = 2-(2-pyridyl)phenyl (Phpy) I; = 7,8-benzoquinolyl (Bzq) II), showing a general formula [{Pd(μ-sac)(C^N)}(2)] with saccharinate 1 displaying a bridging -NCO-coordination mode. Bridge splitting with neutral ligands (L = pyridine (py) 2, quinoline (quinol) 3 or acridine (acrid) 4) yielded new mononuclear derivatives with saccharinate acting as an N-monodentated ligand. Structural characterization by X-ray diffraction of complexes I1, I2 and II2 confirmed the proposed formulae. All complexes emit in the solution and solid state at room temperature. Emission features between 640-680 nm in the solid state for complexes I1 and II1 are significantly red-shifted if compared to the emission in solution. These broad emissions are consistent with the simultaneous presence of (3)ππ* and (3)MMLCT transitions indicating the existence of a strong intramolecular Pd-Pd ground state interaction. The dimeric complexes have also shown to catalyze Suzuki-Miyaura cross-coupling of coumaryl tosylate and aryl boronic acids under phosphine-free conditions. Initial studies suggest the involvement of palladium nanoparticles, which has been further investigated using mercury-drop test and poisoning experiments. 相似文献
90.
A gold nanocage-CNT hybrid for targeted imaging and photothermal destruction of cancer cells 总被引:1,自引:0,他引:1
Khan SA Kanchanapally R Fan Z Beqa L Singh AK Senapati D Ray PC 《Chemical communications (Cambridge, England)》2012,48(53):6711-6713
This communication reports the design of a novel aptamer conjugated gold nanocage decorated SWCNTs hybrid nanomaterial for targeted imaging and selective photothermal destruction of the prostate cancer cells. 相似文献