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An automated method is described for analyzing biological samples originating from CGS 10787B drug disposition studies. The method incorporates a laboratory robot to prepare plasma and urine samples and a high performance liquid chromatographic system to simultaneously analyze for CGS 10787B, as well as metabolites and drug-related compounds (CGS 12094, CGS 17000, and CGS 17001). The robot allquots the biological sample, adds an internal standard, and performs all the steps necessary for the liquid-liquid extraction and concentration of the drug and related components, while operating unattended around the clock. Recovery and reproducibility assessments indicate good accuracy and precision for the method. The limits of detection for the method are 0.2 microgram/mL in plasma and 0.5 microgram/mL in urine, for all components. 相似文献
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Braga WS Kimura NM Luders DD Sampaio AR Santoro PA Palangana AJ 《The European physical journal. E, Soft matter》2007,24(3):247-250
The phase diagram is an interesting field of research, particularly in lyotropic liquid crystals (LLC). In this way, one of the most important phase diagrams of this LLC system was reported by Yu and Saupe. Two uniaxial (calamitic--N(C) and discotic--N(D)) and one biaxial nematic (N(B)) phases were determined by these authors. Furthermore, in this phase diagram the classical isotropic phase (I was observed at high temperature as well as a reentrant isotropic phase (I(RE)) which takes place at lower temperature. Later, this phase diagram was also studied by several authors and in all cases the I(RE)-N(C)-I phase transitions were not observed. In this work, we present a study of this phase diagram through digital image processing and refractometry optical techniques. The occurrence of these phase transitions is investigated and characterized. In addition, the order parameter is obtained based on the Vuks hypothesis from a particular point, in the range of the N(C) phase, where the absolute value of the optical birefringence (Deltan is maximum. 相似文献
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Metal/superconductor/semiconductor (Ag/Hg-1212/CdSe) hetero-nanostructures have been fabricated using pulse-electrodeposition
technique and are characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy
(SEM) studies. The junction capacitance of Ag/Hg-1212, Hg-1212/CdSe and Ag/Hg-1212/CdSe heterojunctions is measured in dark
and under laser irradiation at room temperature. The nature of the junction formed and built-in-junction potentials were determined.
The increase in carrier concentration across the junction due to photo-irradiation has been observed. 相似文献
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One of the innovative technological directions for the high-temperature superconductors has been persued by fabricating the
heteroepitaxial multilayer structures such as superconductor-semiconductor heterostructures. In the present investigation,
metal/superconductor/semiconductor (Ag/Tl-2223/CdSe) hetero-nanostructures have successfully been fabricated using dc electrodeposition
technique and were characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy
(SEM) studies. The measurement of junction capacitance as a function of biasing voltage was used for the estimation of junction
built-in-potential (V
D) and to study the charge distribution in a heterojunction. The Mott-Schottky plots were measured for each junction in dark
and under the photo-irradiation. The effect of laser irradiation on C-V characteristics of hetero-nanostructure has been studied. 相似文献
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An image processing study of a reentrant discotic cholesteric – biaxial cholesteric phase transition
D. D. Luders G. A. Zoner O. R. Santos W. S. Braga A. R. Sampaio N. M. Kimura 《Phase Transitions》2018,91(4):398-405
In this work, we study and characterize the cholesteric sequence of phases (ChDr ? ChB ? ChD), where the first ChDr is the reentrant cholesteric discotic phase, ChB is the cholesteric biaxial phase and the second ChD is the cholesteric discotic phase. This sequence of phases is studied through polarized light microscopy and image processing technique, where, for the first time, the domains and borders of these transitions are established and characterized. They are also investigated and optically characterized throughout their textures. 相似文献
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D. A. Oliveira D. D. Luders G. P. Souza N. M. Kimura A. J. Palangana 《Crystal Research and Technology》2009,44(11):1255-1258
Lyotropic nematic textures are investigated, using optical microscopy, near the reentrant isotropic (IRE) ‐ discotic nematic (ND‐) ‐ biaxial nematic (NB) ‐ calamitic nematic (NC+) ‐ isotropic (I) phase transitions in a lyotropic mixture of potassium laurate, decanol and D2O. The NB, intermediate phase between the two uniaxial nematic ones, is characterized by optical birefringence measurements. In this way, using a polarizing microscope and a colour CCD digital camera, the NB – NC+ phase transition is identified as well as the domain of the NB phase and ND‐ – NB transition point in accordance with optical birefringence data (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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O. R. Santos W. S. Braga D. D. Luders A. R. Sampaio N. M. Kimura M. Simões 《Molecular Crystals and Liquid Crystals》2016,632(1):57-63
ABSTRACTThe nematic phases of a lyotropic system NadS/ decanol/ heavy water are investigated using optical conoscopy and image processing. The phase diagram obtained from these lyotropic materials predicts the occurrence of a direct phase transition, which does not present the biaxial nematic phase, between the discotic (ND) and calamitic (NC) nematic phases. A biaxial nematic (NB) phase is optically characterized and confirmed through conoscopic image, inside the biaxial range, between the two uniaxial nematic phases. Also, their respective transition points are determined by means of image processing. The NB phase observed here is discussed as part of the nature of the micellar configuration of lyotropic materials which exhibit uniaxial nematic phases. 相似文献