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981.
982.
Kishore Kumar Hotha D. Vijaya Bharathi S. Sirish Kumar Y. Narsimha Reddy Pankaj Chatki L. K. Ravindranath K. N. Jaya Veera Ramesh Mullangi 《Biomedical chromatography : BMC》2010,24(10):1100-1107
A highly sensitive, rapid assay method has been developed and validated for the simultaneous estimation of tolmetin (TMT) and MED5 in human plasma with liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive‐ion mode. A simple solid‐phase extraction process was used to extract TMT and MED5 along with mycophenolic acid (internal standard, IS) from human plasma. Chromatographic separation was achieved with 0.2% formic acid–acetonitrile (25:75, v/v) at a flow rate of 0.50 mL/min on an X‐Terra RP18 column with a total run time of 2.5 min. The MS/MS ion transitions monitored were 258.1 → 119.0 for TMT, 315.1 → 119.0 for MED5 and 321.2 → 207.0 for IS. Method validation and clinical sample analysis were performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 20 ng/mL and the linearity was observed from 20 to 2000 ng/mL, for both the anlaytes. The intra‐day and inter‐day precisions were in the range 3.27–4.50 and 5.32–8.18%, respectively for TMT and 4.27–5.68 and 5.32–8.85%, respectively for MED5. This novel method has been applied to a clinical pharmacokinetic study. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
983.
984.
The geometry dependent resistance models are used to estimate the effective thermal conductivity of two-phase materials based on the unit cell approach. The algebraic equations are derived based on isotherm approach for various geometries. The effective thermal conductivity of the above models are found and compared with experimental data with a minimum and maximum deviation of ±3.976 and ±19.55%, respectively. The present models are good agreement with experimental results. 相似文献
985.
986.
K.C. Majumdar Randhir Kumar Sinha Santanu Chakravorty 《Journal of Physics and Chemistry of Solids》2009,70(8):1171-915
The miscibility of a rod-shaped (R) and a bent-shaped (BC) compound forming an induced B1 phase is reported. B1 phase is not present in both R and BC in the entire phase sequence. R exhibits partially bilayered smectic Ad phase with cholesteric and TGB while BC shows a B2 phase. It is interesting to show that the B2 phase is totally diminished in low composition (weight%) of BC, B1 phase is induced at lower temperature range (~90-135 °C). A dielectric study is also incorporated to confirm the induction of B1 phase in the binary mixture. 相似文献
987.
O. El Gawhary N. Kumar S. F. Pereira W. M. J. Coene H. P. Urbach 《Applied physics. B, Lasers and optics》2011,105(4):775-781
Scatterometry is a well established technique currently utilized in research, as well as in industrial applications, to retrieve
the properties of a given scatterer (the target) by looking at how the light coming from a certain source is diffracted in
the far field. Currently the light source is often a discharge lamp that, after wavelength filtering, can be thought as a
quasi-monochromatic, but spatially incoherent, source. In the present work, benefits of using a focused spot from a spatially
coherent light source, as that emitted by a laser, are investigated on a theoretical viewpoint. The focused spot is scanned
over the object of interest and, for each scan position, a far-field diffraction pattern is recorded. Our results show that
spatially coherent light can sensibly increase the accuracy of the technique with respect to the target’s geometrical profile. 相似文献
988.
J. Manjunath Swamy Narendra Kamath Anil Kumar Radha Shekar Nuggehally R. Srinivas Fjalar Kristjansson 《Biomedical chromatography : BMC》2010,24(5):528-534
Sensitivity enhancement via summation of multiple MRM transition pairs is gaining popularity in tandem mass spectrometric assays. Numerous validation experiments describing the assays for two model substrates, clopidogrel and ramiprilat, were performed. The quantitation of clopidogrel was achieved by the summation of transition pairs m/z 322.2 to m/z 212.0 and m/z 322.2 to m/z 184.0, while that of ramiprilat was achieved by the summation of transition pairs m/z 389.2 to m/z 206.1 and m/z 389.2 to m/z156.1. The use of summation approach achieved sensitivities of >2 fold for both compounds as compared with the reported single MRM transition pair assays. The validation experiments addressed some important assay development issues, such as: (a) lack of impact of matrix effect; (b) unequivocal verification of the percentage contribution of each MRM transition pair towards sensitivity; (c) sensitivity enhancement factor achieved by summation approach of MRM transition pairs; and (d) accurate prediction of quality control samples using summation approach vs a single MRM transition pair. In summary, the appropriateness of using two MRM transition pairs for quantitation was demonstrated for both clopidogrel and ramiprilat. Additionally, pharmacokinetic application of the MRM transition pair assays using a summation approach was established for the two compounds. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
989.
We present a new method for resolving combinatorial ambiguities that arise in multi-particle decay chains at hadron colliders where the assignment of visible particles to the different decay chains has ambiguities. Our method, based on selection cuts favoring high transverse momentum and low invariant mass pairings, is shown to be significantly superior to the more traditional hemisphere method for a large class of decay chains, producing an increase in signal retention of up to a factor of 2. This new method can thus greatly reduce the combinatorial ambiguities of decay chain assignments. 相似文献
990.
Zhihui Yi Luca Giacomo Bettini Gaia Tomasello Prajwal Kumar Paolo Piseri Irina Valitova Paolo Milani Francesca Soavi Fabio Cicoira 《Journal of Polymer Science.Polymer Physics》2017,55(1):96-103
Planar organic electrochemical transistors (OECTs) using PEDOT:PSS as the channel material and nanostructured carbon (nsC) as the gate electrode material and poly(sodium 4‐styrenesulfonate (PSSNa) gel as the electrolyte were fabricated on flexible polyethylene terephthalate (Mylar®) substrates. The nsC was deposited at room‐temperature by supersonic cluster beam deposition (SCBD). Interestingly, the OECT acts as a hybrid supercapacitor (to give a device that we indicate as transcap). The energy storage ability of transcaps has been studied with two cell configurations: one featuring PEDOT:PSS as the positive electrode and nsC as the negative electrode and another configuration with reversed electrode polarity. Potentiostatic charge/discharge studies show that both supercapacitors show good performance in terms of voltage retention, in particular, when PEDOT:PSS is used as the positive electrode. Galvanostatic charge–discharge characteristics show typical symmetric triangular shape, indicating a nearly ideal capacitive behavior with a high columbic efficiency (close to 100%). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 96–103 相似文献