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481.
Optical and Quantum Electronics - Evaluation of polarization control by polarization attractor based on stimulated Raman scattering in optical fiber is presented. Performed simulations are...  相似文献   
482.
JPC – Journal of Planar Chromatography – Modern TLC - The present era is witnessed by the increasing demand for herbal medicine. Therefore, the preparation of herbal drugs is warranted...  相似文献   
483.
Duvelisib is a dual inhibitor of phosphoinositide 3 kinase that received global approval by the US Food and Drug Administration in 2018 to treat follicular lymphoma after at least two prior systemic therapies. An extensive literature search revealed that, to date, metabolites of duvelisib have not been characterized and information on them is not available in any of the literature. Moreover, the metabolism pathway is yet to be established. This study aimed to investigate and characterize the metabolites of duvelisib generated in microsomes and S9 fractions. In this study, five duvelisib metabolites were identified using UHPLC–Q-TOF–MS/MS analysis technique. The structural characterization of the metabolites was performed by comparing the fragmentation pattern of duvelisib and its metabolites through an accurate mass measurement technique. Three metabolites were generated through phase I hydroxylation and dechlorination reactions. The other two metabolites were generated through a phase II glucuronidation reaction. The metabolism mechanism established through this study can be useful to improve the safety profile of drugs of similar categories in the future after establishment of the toxicity profile of the identified metabolites.  相似文献   
484.
During last few decades accurate determination of protein structural class using a fast and suitable computational method has been a challenging problem in protein science. In this context a meaningful representation of a protein sample plays a key role in achieving higher prediction accuracy. In this paper based on the concept of Chou's pseudo amino acid composition (Chou, K.C., 2001. Proteins 43, 246-255), a new feature representation method is introduced which is composed of the amino acid composition information, the amphiphilic correlation factors and the spectral characteristics of the protein. Thus the sample of a protein is represented by a set of discrete components which incorporate both the sequence order and the length effect. On the basis of such a statistical framework a simple radial basis function network based classifier is introduced to predict protein structural class. A set of exhaustive simulation studies demonstrates high success rate of classification using the self-consistency and jackknife test on the benchmark datasets.  相似文献   
485.
486.
Polymer ceramic composites using a polymer binder, nanosized BaTiO3 and metal particles were developed for radiation shielding in the microwave region. From X-ray Diffraction (XRD) the crystallinity and nanosize of BaTiO3 was confirmed in the composite. Interesting changes in Differential Scanning Calorimetry (DSC) were observed before and after ball milling of BaTiO3. Shielding Efficiency (SE) of microwave radiation has been measured from transmitted fraction (TF) of electromagnetic waves (EM) at different frequencies. The changes in TF were assigned to reflection and absorption of EM waves in different composites.  相似文献   
487.
Quasielastic scattering angular distributions have been measured for the 7Be + 9Be system at E lab = 17 , 19 and 21MeV in the angular range $ \theta_{{cm}}^{}$ = 24° - 57° . An optical model (OM) analysis of these data has been carried out in order to extract optical potential parameters and reaction cross-sections. One-proton stripping cross-sections were also measured for this system at E lab = 19 and 21MeV. These transfer angular-distribution data were compared with the finite-range distorted-wave Born approximation (FRDWBA) calculations. For the 7Li + 9Be system quasielastic scattering angular distributions were measured and emitted light charged particles were detected at E lab = 15.75 , 24.00 and 30.00MeV in the angular range $ \theta_{{cm}}^{}$ = 7° - 70° . Fusion cross-sections were obtained by reproducing the measured $ \alpha$ -evaporation spectra from the compound nucleus at backward angles with the statistical model calculations. The ratios of the experimental fusion cross-sections to the total reaction cross-sections (obtained from OM analysis) were found to be small. This result suggests that the break-up process has a strong influence on the fusion process leading to a reduction in the fusion cross-section.  相似文献   
488.
Journal of Nanoparticle Research - CdSe nanocrystalline thin films have been synthesized on indium tin oxide (ITO) substrates by an electrodeposition technique. A Schottky junction device in the...  相似文献   
489.
Li has introduced the concepts of inverse system and direct system for fuzzy topological spaces and studied inverse limits and direct limits on such spaces by presenting the explicit constructions of these limits.In this paper some important concepts of fuzzy topology,such as,product fuzzy topology,quotient fuzzy topology,fuzzy continuity etc.,are used for further study of inverse limits and direct limits for fuzzy topological spaces.  相似文献   
490.
The densities (ρ) and ultrasonic velocities (C) of binary mixture of diisopropyl ether (DIPE) and bromobenzene (BB) have been measured at different frequencies (1 MHz, 3 MHz and 5 MHz) over the entire range of mole fraction of diisopropyl ether (DIPE) at temperature 303 K. The intermolecular free length (L f ), isentropic compressibility (β), acoustic impedance (Z) and excess values of isentropic compressibility (β E ) and acoustic impedance (ZE) have been computed using values of ultrasonic velocity (C) and density (ρ). The ultrasonic velocity, intermolecular free length are positive whereas the excess values of isentropic compressibility and acoustic impedance are negative over the entire composition range of DIPE which indicates presence of specific interactions between unlike molecules. The results are discussed in the light of intermolecular interactions occurring in the mixtures.   相似文献   
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