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51.
Green tea extracts (GTE) has been reported to be a kinase inhibitor and modulator for various drug metabolizing enzymes. It may give synergetic antioncogenic effect, but with a possibility of pharmacokinetic interactions with various co‐administered anticancer agents like palbociclib (PAL), a selective inhibitor of CDK‐4/6 primarily metabolized by CYP3A enzyme. To explore the impact of GTE on PAL pharmacokinetics in Sprague–Dawley rats, a rapid and sensitive UHPLC–QTOF–MS method was established. Chromatographic separation was carried out on an Acquity UPLC BEH C18 (100 × 2.1 mm, 1.7 μm) column using a gradient mobile phase system consisting of 0.1% formic acid and acetonitrile. Sample preparation was based on a simple protein precipitation method. Estimation of target ions [M + H]+ at m/z 448.2455 for PAL and m/z 441.2044 for ibrutinib (IS) was performed in selective ion mode ESI–HRMS. Good sensitivity (1.0 ng/mL) and linearity over a wide concentration range of 1–2000 ng/mL was exhibited by the method. The results indicated that the administration of GTE resulted in decreased oral bioavailability of PAL in both short‐ and long‐term conditions. However, when both conditions were compared, the variation was less for the peak concentration and area under the concentration–time curve level of PAL.  相似文献   
52.
The European Physical Journal E - To theoretically understand force generation properties of actin filaments, many models consider growing filaments pushing against a movable obstacle or barrier....  相似文献   
53.
The present study reports the synthesis of Ce0.8Sm0.2O1.9 solid electrolyte by a novel proteic sol‐gel method which uses gelatin as polymerizing agent. The as‐synthesized powder material was calcined at 700 °C for 2 h, with X‐ray diffraction revealing a single cubic phase with lattice parameter a = 0.5435 nm and theoretical density of 7.144 gcm‐3. The average crystallite size is 12 nm, as determined by the Scherrer equation. Impedance spectroscopy revealed a larger resistive contribution of the grain boundaries than that from grain bulk, which, due to its lower activation energy, tends to dominate the total conductivity above 650 °C. The total conductivity is in line with literature data for ceramics of the same composition prepared by various methods, thus confirming the potential of the proteic sol‐gel method as a green, low cost alternative synthetic route to prepare ceria‐based solid electrolytes.  相似文献   
54.
Track etch membranes (TEMs) program at 14 UD Pelletron accelerator at TIFR, Mumbai, India using 25 micron thick polyethylene terepthalate film is described. Large scale preparation of TEMs by scanning heavy ion beams using a electromagnetic scanner and rolling mechanism using a geared D.C. motor and vacuum rotary feed through are presented. The selection of ions of suitable energy and etching parameters for making various pore sizes were investigated using Rutherford scattered beam from Pelletron accelerator. Pore size and pore density were measured using scanning electron microscope. Scanning width up to 35 cm and irradiation up to 22 m were successfully carried out using this facility. Some applications carried out using these membranes are also mentioned.  相似文献   
55.
Multi chelating hydrogels (MCHs) were synthesized using a simple radical polymerization method from acrylamide, hydroxyethyl acrylate, and N‐(2‐aminothiozolyl)maleamic acid (AMA) monomers, methylenebisacrylamide (MBA) a cross‐linker, and azobisisobutyronitrile (AIBN) an initiator. The resulting MCHs were characterized with Fourier transform infrared spectroscopy and scanning electron microscopy to confirm the formation and morphological properties. The MCHs were highly swellable in aqueous solutions as well as different pH conditions. MCHs were applied to evaluate uptake behavior of Uranium (VI) ion from aqueous solutions. Batch adsorption studies were performed by varying experimental conditions like contact time, pH, and initial metal ion concentration. The kinetics data was best suited with the second‐order equation model. The equilibrium adsorption data was correlated with Langmuir and Freundlich isotherm models. This study suggests that maximum Uranium (VI) ion uptake has been found to be 288 mg.g?1 and regenerated for 5 cycles without any significant change. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
56.
Homogeneous coating of carbon nanotubes with metallic nanoparticles was achieved using supramolecular auto-organization of amphiphilic molecules as template. The resulting Pd nanoparticles/carbon nanotube nanohybrids were then evaluated in electrocatalysis experiments, showing superior activity in ethanol oxidation compared to analogous systems.  相似文献   
57.
2-Aminopyridinium ions were found to activate nitroalkenes toward conjugate addition of heteroaromatic compounds with low catalyst loadings and the Diels-Alder reaction with the periselectivity opposite to that observed with metal Lewis acids, raising the possibility that a 2-aminopyridinium core might be a promising catalaphore for the asymmetric catalyst design.  相似文献   
58.
Gold(II) complexes are rare, and their application to the catalysis of chemical transformations is underexplored. The reason is their easy oxidation or reduction to more stable gold(III) or gold(I) complexes, respectively. We explored the thermodynamics of the formation of [AuII(L)(X)]+ complexes (L=ligand, X=halogen) from the corresponding gold(III) precursors and investigated their stability and spectral properties in the IR and visible range in the gas phase. The results show that the best ancillary ligands L for stabilizing gaseous [AuII(L)(X)]+ complexes are bidentate and tridentate ligands with nitrogen donor atoms. The electronic structure and spectral properties of the investigated gold(II) complexes were correlated with quantum chemical calculations. The results show that the molecular and electronic structure of the gold(II) complexes as well as their spectroscopic properties are very similar to those of analogous stable copper(II) complexes.  相似文献   
59.
We report enhanced anomalous photovoltaic effects and switchable photovoltage generation in pure and Pr–Cr co‐doped BiFeO3 (BFO) nanotubes (NTs). Influence of metal doping on short circuit current, open circuit voltage, power conversion efficiency and fill factor are investigated. The power conversion efficiency of pure BFO NTs (~0.207%) is found to be enhanced by several orders of magnitude in comparison with the reported bulk effect. Pr‐doped NTs provide highest values of power conversion efficiency (~0.5%).

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60.
The effect of glass additives on the densification, phase evolution, microstructure and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 (BMT) was investigated. Different weight percentages of quenched glass such as B2O3, SiO2, B2O3-SiO2, ZnO-B2O3, 5ZnO-2B2O3, Al2O3-SiO2, Na2O-2B2O3·10H2O, BaO-B2O3-SiO2, MgO-B2O3-SiO2, PbO-B2O3-SiO2, ZnO-B2O3-SiO2 and 2MgO-Al2O3-5SiO2 were added to calcined BMT precursor. The sintering temperature of the glass-added BMT samples were lowered down to 1300 °C compared to solid-state sintering where the temperature was 1650 °C. The formation of high temperature satellite phases such as Ba5Ta4O15 and Ba7Ta6O22 were found to be suppressed by the glass addition. Addition of glass systems such as B2O3, ZnO-B2O3, 5ZnO-2B2O3 and ZnO-B2O3-SiO2 improved the densification and microwave dielectric properties. Other glasses were found to react with BMT to form low-Q phases which prevented densification. The microwave dielectric properties of undoped BMT with a densification of 93.1% of the theoretical density were εr=24.8, and Qu×f=80,000. The BMT doped with 1.0 wt% of B2O3 has Qu×f=124,700, εr=24.2, and . The unloaded Q factor of 0.2 wt% ZnO-B2O3-doped BMT was 136,500 GHz while that of 1.0 wt% of 5ZnO-2B2O3 added ceramic was Qu×f=141,800 GHz. The best microwave quality factor was observed for ZnO-B2O3-SiO2 (ZBS) glass-added ceramics which can act as a perfect liquid-phase medium for the sintering of BMT. The microwave dielectric properties of 0.2 wt% ZBS-added BMT dielectric was Qu×f=152,800 GHz, εr=25.5, and .  相似文献   
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