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1.
Dr. Kathiravan Murugesan Vishwas G. Chandrashekhar Dr. Carsten Kreyenschulte Prof. Dr. Matthias Beller Dr. Rajenahally V. Jagadeesh 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17561-17565
Herein, we report the synthesis of specific silica-supported Co/Co3O4 core–shell based nanoparticles prepared by template synthesis of cobalt-pyromellitic acid on silica and subsequent pyrolysis. The optimal catalyst material allows for general and selective hydrogenation of pyridines, quinolines, and other heteroarenes including acridine, phenanthroline, naphthyridine, quinoxaline, imidazo[1,2-a]pyridine, and indole under comparably mild reaction conditions. In addition, recycling of these Co nanoparticles and their ability for dehydrogenation catalysis are showcased. 相似文献
2.
The structural phase transition from orthorhombic (T) phase to tetragonal (T′) phase in substituted La2−x
R
x
CuO4 (R = Pr, Nd, Sm, Eu and Gd) and T′ to T-phase in Pr2−x
M
x
CuO4−y
(M = Sr, Ca) has been studied by X-ray diffraction technique. The T-phase of La2CuO4 is transferred to T′ phase abruptly atx=0.8, 0.4, 0.4, 0.3 and 0.4 respectively for substitution of Pr, Nd, Sm, Eu and Gd for La in La2CuO4 without evidence of the T* phase. The T′ structure of Pr2CuO4 (x = 0.0) gets transformed to the T* structure at 30% Ca doping (x=0.6) and then to the T structure at 50% Ca doping (x=1.0), while for Sr-contentx=0.0, 0.4 and 1.0 it shows T′, T* and T structure respectively. 相似文献
3.
Prof. Dr. Christian Brückner Dr. Nivedita Chaudhri Dustin E. Nevonen Dr. Sayantan Bhattacharya Arthur Graf Elizabeth Kaesmann Dr. Ruoshi Li Dr. Matthew J. Guberman-Pfeffer Prof. Dr. Tomoyasu Mani Dr. Arunpatcha Nimthong-Roldán Dr. Matthias Zeller Dr. Adrien A. P. Chauvet Prof. Dr. Victor Nemykin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16189-16203
4.
5.
M. Munawar Chaudhri ‡ 《哲学杂志》2013,93(27):2877-2903
Experimental investigations of the response of several elastic solids, carried out using an instrumented indentation machine, are described. These solids include a natural rubber compound, neoprene, and three different compositions of poly(dimethylsiloxane) (PDMS) when they were indented with tungsten carbide cones of included angles of 60°, 90°, 120° and 136°. It is shown that, except for the case of the 60° cone loading on to the blocks of PDMS (1?:?10) and PDMS (1?:?20), the indentation load versus indenter displacement behaviour of all the elastic solids corresponding to all the conical indenters is well fitted by the 1965 Sneddon theory for frictionless indentations. Video camera sequences of the process of indentation by cones of different included angles into the blocks of PDMS (1?:?10) and PDMS (1?:?20) have also been taken from which measurements of the elastic deformation of the indented surface have been made. It is shown that the magnitude of the elastic deformation of the indented surface closely agrees with the theory when the blocks are indented with cones of included angles of 90°, 120° and 136°. However, for the case of the 60° cone, there is again a discrepancy between experiment and theory; the magnitude of the deformation is significantly smaller than that predicted theoretically. It is suggested that the discrepancy between theory and experimental observations may be due to a non-zero coefficient of friction between the 60° conical indenter and the blocks of PDMS (1?:?10) and PDMS (1?:?20). It is also shown experimentally that, for indenter loading speeds in the range 0.2–200?mm?min?1, no time-dependent effects were observed for the loading curves, thus justifying the use of the theory given by Love in and of the Sneddon theory of conical indentations of elastic solids. Finally, using the findings described in this work, a brief discussion is included to explain the discrepancy between the results obtained by Sabey in and those obtained by Greenwood and Tabor in the same year when tyre-tread rubber specimens obtained from a single source were indented with steel cones of different included angles. 相似文献
6.
Preeti Jain Vandna Singh Sabir Ali Vishwas Tripathi Upendra Saraswat 《Journal of Saudi Chemical Society》2018,22(5):546-557
Macrocyclic Schiff base ligand through the condensation of 1,3-dicarbonyl-phenyl-dihydrazide with 4,4′-difluorobenzil and its Co(II), Ni(II), Cu(II) and Zn(II) metal complexes have been synthesized. The ligand and metal complexes were characterized by analytical and physicochemical methods. An octahedral geometry arising from coordination of N2O2 donor atoms from the macrocyclic framework has been proposed for all metal complexes. Synthesized ligand and metal complexes were investigated for in vitro antibacterial and antioxidant activity. Complex [Ni(C22H14N4F2O2)(OCOCH3)2] has shown remarkable antibacterial activity (Minimum inhibitory concentration 8–16?μg/ml) comparable to commercial antibiotic Ciprofloxacin. Anticancer activity of synthesized compounds against Squamous Cell Carcinoma (SCC4), head and neck cancer cell line has also been studied at different concentrations and at different time points. Complexes [Co(C22H14N4F2O2)(NO3)2] and [Cu(C22H14N4F2O2)(OCOCH3)2] have shown remarkable anticancer results (IC50 31.1 and 43.1?μM) against the tested cell line in concentration dependent manner. Molecular docking studies were carried out to find the binding mode of the synthesized macrocyclic Schiff base ligand to Epidermal Growth Factor Receptor (EGFR) Kinase (PDB ID: 1M17). 相似文献
7.
Satish R. Patil Ketan K. Nerurkar Ashok M. Kalamkar Vishwas Pukale Kiran V. Mangaonkar Satish G. Pingale 《Journal of mass spectrometry : JMS》2012,47(1):23-28
An analytical method based on liquid–liquid extraction has been developed and validated for analysis of agomelatine in human plasma. Fluoxetine was used as an internal standard for agomelatine. A Betasil C18 (4.0 × 100 mm, 5 µm) column provided chromatographic separation of analytes followed by detection with mass spectrometry. The method involves simple isocratic chromatographic conditions and mass spectrometric detection in the positive ionization mode using an API‐4000 system. The proposed method has been validated with linear range of 0.050–8.000 ng/ml for agomelatine. The intra‐run and inter‐run precision values are within 12.12% and 9.01%, respectively, for agomelatine at the lower limit of quantification level. The overall recovery for agomelatine and fluoxetine was 67.10% and 72.96%, respectively. This validated method was used successfully for analysis of plasma samples from a pharmacokinetic study. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
8.
The effect of different mineral acids on the absorption signals of lead and cadmium in atomic absorption spectrometry is reported. The behaviour of the signals was studied with respect to variations in metal concentration, acid concentration, flame stoichiometry and burner height. For the determination of lead and cadmium the most suitable concentrations of hydrochloric, nitric, sulphuric and perchloric acids were 5, 5, 2.5 and 5%, respectively. Similar absorption behaviour was observed in oxidizing and reducing flames for lead and cadmium in all the acids studied. 相似文献
9.
M. A. Chaudhri Q. Jabbar Q. Nadeem 《Journal of Radioanalytical and Nuclear Chemistry》2003,257(1):211-213
Production yields of all the isotopes, with Z = 20 to >92, under bombardment with protons, deuterons and alphas of up to 36 MeV, have been estimated using empirically constructed excitation functions and our simplified method. Results are presented in graphical form, from which the production yield of any isotope in the aforementioned range can be directly obtained for an infinitely thick (stopping the incoming beam completely), moderately thick or even a thin target under given irradiation conditions. These yields would not only help to select the best reaction to produce a particular isotope and help in minimizing the losses due to further processing of the isotopes but would also provide an indication of the unwanted activities which are also being produced simultaneously. 相似文献
10.
M. A. Chaudhri M. N. Chaudhri Q. Nadeem Q. Jabbar 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(3):701-703
A new method for non-destructive depth profiling of fluorine has been developed which extends the profiling range to much
larger depths than hitherto possible. In this method the thick-target yield of 6–7 MeV gammas from the reaction of 19F(p,αγ) 16O in the tooth sample, was measured as a function of the incident energy from threshold to up to 2.7 MeV and the yield curve
plotted. This curve was compared to the calculated yield curve of 6–7 MeV gammas from the same reaction but on an enamel matrix
containing uniformly distributed fluorine. The difference in the shape of the two curves was only due to the non-uniform distribution
of fluorine in the tooth sample, which could then be calculated. By making use of this method F-depth profiles in teeth of
monkeys were determined non-destructively to a depth of 14 μm. This method is also applicable for profiling other elements
through appropriate resonant or non-resonant nuclear reactions. 相似文献