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31.
Preparation,characterization and heterogeneous catalytic applications of GO/Fe3O4/HPW nanocomposite in chemoselective and green oxidation of alcohols with aqueous H2O2 下载免费PDF全文
Graphene oxide ‐ Fe3O4 ‐ NH3+H2PW12O40 ‐ magnetic nanocomposite (GO/Fe3O4/HPW) was prepared by linking amino ‐ functionalized Fe3O4 nanoparticles (Fe3O4 ‐ NH2) on the graphene oxide (GO), and then grafting 12 ‐ tungstophosphoric acid (H3PW12O40) on the graphene oxide ‐ magnetite hybrid (GO ‐ Fe3O4 ‐ NH2). The obtained GO/Fe3O4/HPW nanocomposite was well characterized with different techniques such as FT ‐ IR, TEM, SEM, XRD, EDX, TGA ‐ DTA, AGFM, ICP and BET measurements. The used techniques showed that the graphene oxide layers were well prepared and the various stages of preparation of the GO/Fe3O4/HPW nanocomposites successfully completed. This new nanocomposite displayed excellent performance as a heterogeneous catalyst in the oxidation of alcohols with H2O2. The as ‐ prepared GO/Fe3O4/HPW catalyst was more stable and recyclable at least five times without significantly reducing its catalytic activity. 相似文献
32.
An evaluation of the CYP2D6 and CYP3A4 inhibition potential of metoprolol metabolites and their contribution to drug–drug and drug–herb interaction by LC‐ESI/MS/MS 下载免费PDF全文
Roshan M. Borkar Murali Mohan Bhandi Ajay P. Dubey V. Ganga Reddy Prashanth Komirishetty Prajwal P. Nandekar Abhay T. Sangamwar Ahmed Kamal Sanjay K. Banerjee R. Srinivas 《Biomedical chromatography : BMC》2016,30(10):1556-1572
The aim of the present study was to evaluate the contribution of metabolites to drug–drug interaction and drug–herb interaction using the inhibition of CYP2D6 and CYP3A4 by metoprolol (MET) and its metabolites. The peak concentrations of unbound plasma concentration of MET, α‐hydroxy metoprolol (HM), O‐desmethyl metoprolol (ODM) and N‐desisopropyl metoprolol (DIM) were 90.37 ± 2.69, 33.32 ± 1.92, 16.93 ± 1.70 and 7.96 ± 0.94 ng/mL, respectively. The metabolites identified, HM and ODM, had a ratio of metabolic area under the concentration–time curve (AUC) to parent AUC of ≥0.25 when either total or unbound concentration of metabolite was considered. In vitro CYP2D6 and CYP3A4 inhibition by MET, HM and ODM study revealed that MET, HM and ODM were not inhibitors of CYP3A4‐catalyzed midazolam metabolism and CYP2D6‐catalyzed dextromethorphan metabolism. However, DIM only met the criteria of >10% of the total drug related material and <25% of the parent using unbound concentrations. If CYP inhibition testing is solely based on metabolite exposure, DIM metabolite would probably not be considered. However, the present study has demonstrated that DIM contributes significantly to in vitro drug–drug interaction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Journal of Thermal Analysis and Calorimetry - Based on the data of the literature reports, the Al–Zr binary system has been re-assessed thermodynamically through the CALPHAD (CALculations of... 相似文献
35.
Osman Ayop Mohamad Kamal A. Rahim Noor Asniza Murad Huda A. Majid 《Applied Physics A: Materials Science & Processing》2014,117(2):651-656
This paper presents the analysis of circular ring metamaterial absorber with the existing of copper lines. The structure is designed using lossy FR4 substrate with thin copper layers. The circular ring shape with copper lines is printed on the top surface of FR4 substrate, while at the bottom surface is printed with full copper ground plane. Parametric study is done to investigate the effect of copper lines on the resonance frequency. From the simulation, the circular ring metamaterial absorber with vertical copper lines can resonates at lower frequency, but this structure is polarized sensitive. This drawback can be improved by adding horizontal copper lines together with the vertical copper lines. The circular ring structure with vertical and horizontal copper lines is not only polarization insensitive, but it can works at wide operating angle of incident waves. 相似文献
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Mehrdad Nikravech Kamal Baba Bernard Leneindre Frédéric Rousseau 《Chemical Papers》2012,66(5):502-510
Processing the aerosol of metal salts in non-equilibrium plasma represents a promising technique that combines the advantages
of spray pyrolysis with the high reactivity of plasmas at nearlaboratory temperature in order to produce mixed-oxides and
perovskite materials. The aim of this paper is to describe the principles of this new technique and to present the various
applications and latest developments. This technique’s capacity to deposit various mixed metal oxides with precise stoichiometry
is demonstrated. It is shown that oxidant plasma species play a key role in the chemical transformation of starting materials
into oxides at laboratory temperature, while the configuration of the reactor determines the morphology and texture of the
deposited layers. Two different reactor configurations are presented. The porous layers of La
x
Sr1−x
MnO3 as the cathode for fuel cells were synthesised in a wave shock reactor configuration, while nanostructured ZnO-Al layers
to form a transparent conductive cathode for photovoltaic cells were deposited in the spray plasma reactor of the latest generation
for this technique. The experimental results emphasise the role of plasma species in the rate of chemical reactions and in
the chemical composition of the deposited layers. 相似文献
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Lakhera Shradha Rana Meenakshi Devlal Kamal Celik Ismail Yadav Rohitash 《Structural chemistry》2022,33(3):703-719
Structural Chemistry - Tridax procumbens is a flowering plant of the Asteraceae family with a wide range of medicinal uses like anti-inflammatory, anti-diabetic, anti-microbial, immunomodulatory,... 相似文献