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1.
2.
A method for the construction of the second constant of motion in fourth order is carried out. Correspondingly the fourth order potential equation is obtained whose solutions directly provide the classical integrable systems. Second constant of motion is obtained for a large class of potentials. Quantum invariants are also obtained with second order quantum corrections of the order O(?2) to the corresponding classical invariants. The phase space diagrams for these cases are drawn using a mathematical computer software package in two dimensions. 相似文献
3.
The 57Fe Mössbauer technique has been used to investigate the effect of zinc oxide substitution in (25???x)MnO–xZnO–15Fe2O3–60B2O3 glass system (x?=?0, 5, 10, 15 and 20 mol% of ZnO ). Mössbauer absorption spectra for all the samples recorded at room temperature suggest the existence of the two paramagnetic quadrupole doublets. The observed variations in hyperfine parameters have been explained on the basis of cations distribution and exchange interaction at the lattice sites and it is concluded that B–B interaction increases while the metal–metal interaction decreases due to replacement of manganese oxide by zinc oxide. These results suggest that the present glass system exhibits a paramagnetic behaviour that changes towards the weak paramagnetic when manganese oxide was replaced with zinc oxide. 相似文献
4.
V. Goliáš D. Pittauerová R. Procházka Z. Třískala 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(3):461-470
Summary The activities of218Po,214Po and211Bi were determined in samples obtained of soil/gas. Sampling work was taken in Jáchymov (Czech Republic) at the outcrop of
the Geister-vein,by electrostatic precipitation from filtered soil gas on stainless steel disks.The samples were measured
in a field laboratory using a semi-conductor alpha-spectrometer.The activities of218Po,214Po and211Bi were calculated.Samples taken from active dump material (near-by radon source) exhibited a high211Bi/214Po ratio, while those of the vein outcrop (a relatively deeper source) had a low ratio.A mathematical model was employed to
determine the radon age calculated from the actinon/radon input ratio.This varied in a range of 5.6 to -7.7 seconds.Negative
age values are probably caused by the preference for actinon, which rapidly comes into equilibrium with the source of this
gas. 相似文献
5.
Zusammenfassung Es werden die Resultate des isothermen Zerfalles und der Reduktion vonstandardisiertem Ammoniumpolyuranat im Bereich von 285 bis 463° C (in Wasserstoff) wiedergegeben. Der Zerfall zu UO3 wurde schon bei einer Temp. unter 290° C festgestellt, diese Phase blieb jedoch darauf stabil bis 320° C. Zwischen 320° C und 380° C verläuft die Reduktion zu U3O8, über 380° C aber zu UO2. Die Aktivierungsenergien bei der Reduktion von UO3 zu U3O8 und von U3O8 zu UO2 wurden berechnet, und zwar 32,2 kcal/g-mol und 41,7 kcal/g-mol. Die Ergebnisse können mit den Literaturangaben für die Reduktion der einzelnen Phasen UO3 und U3O8 verglichen werden. Die beobachteten Unterschiede weisen auf den Einfluß der Aktivität der Präparate hin.
Mit 4 Abbildungen 相似文献
The isothermal decomposition and reduction of ammonium polyuranate (ADU) was investigated in the temperature interval 285–463° C in hydrogen. The formation of UO3 was noticed below 290° C and this product was stable up to 320° C. U3O8 was stable from this temperature on up to 380° C, where the reduction to UO2 was observed. The activation energies 32,2 Kcal/mole and 41.7 Kcal/mole were calculated for the reduction of UO3 to U3O8 and for the reduction of U3O8 to UO2, respectively. The results are comparable with the published data on reduction of separate phases UO3 and U3O8. Some differences noticed show the influence of the activities of the products.
Mit 4 Abbildungen 相似文献
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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
8.
Samuel O. Grim Mudlagiri B. Goli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract 1,1-Bis(diphenylphosphino)ethene, 1a, was originally prepared by Colquhoun and McFarlane1 by the reaction of lithium diphenylphosphide and vinylidene chloride. Subsequently, Schmidbaur et al.,2 reported further novel chemistry of 1a and its derivatives such as 1b and 1c. 相似文献
9.
Hetero‐tri‐spin [2p‐3d‐4f] Chain Compounds Based on Nitronyl Nitroxide Lanthanide Metallo‐Ligands: Synthesis,Structure, and Magnetic Properties 下载免费PDF全文
Mei Zhu Peng Hu Yungai Li Xiufeng Wang Prof. Licun Li Prof. Daizheng Liao V. M. L. Durga Prasad Goli Prof. S. Ramasesha Dr. Jean‐Pascal Sutter 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13356-13365
Employing nitronyl nitroxide lanthanide(III) complexes as metallo‐ligands allowed the efficient and highly selective preparation of three series of unprecedented hetero‐tri‐spin (Cu?Ln‐radical) one‐dimensional compounds. These 2p–3d–4f spin systems, namely [Ln3Cu(hfac)11(NitPhOAll)4] (LnIII=Gd 1Gd , Tb 1Tb , Dy 1Dy ; NitPhOAll=2‐(4′‐allyloxyphenyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide), [Ln3Cu(hfac)11(NitPhOPr)4] (LnIII=Gd 2Gd , Tb 2Tb , Dy 2Dy , Ho 2Ho , Yb 2Yb ; NitPhOPr=2‐(4′‐propoxyphenyl)‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide) and [Ln3Cu(hfac)11(NitPhOBz)4] (LnIII=Gd 3Gd , Tb 3Tb , Dy 3Dy ; NitPhOBz=2‐(4′‐benzyloxyphenyl)‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide) involve O‐bound nitronyl nitroxide radicals as bridging ligands in chain structures with a [Cu‐Nit‐Ln‐Nit‐Ln‐Nit‐Ln‐Nit] repeating unit. The dc magnetic studies show that ferromagnetic metal–radical interactions take place in these hetero‐tri‐spin chain complexes, these and the next‐neighbor interactions have been quantified for the Gd derivatives. Complexes 1Tb and 2Tb exhibit frequency dependence of ac magnetic susceptibilities, indicating single‐chain magnet behavior. 相似文献
10.
Neha Batra Vinoth Rajendran Ishan Wadi Ankit Lathwal Roshan Kumar Dutta Prahlad C. Ghosh Rinkoo D. Gupta Mahendra Nath 《Journal of heterocyclic chemistry》2020,57(4):1625-1636
A series of benzenesulfonamide-appended [1,2,3]-triazole hybrids was synthesized by using [3 + 2] cycloaddition of primary, secondary, and tertiary sulfonamide azides with various phenoxymethylacetylenes under click reaction conditions. After structural characterization, the compounds were subjected to in-silico absorption, distribution, metabolism, excretion and toxicity (ADMET) screening to evaluate their drug-likeness and other pharmacokinetic parameters. Furthermore, their in vitro antiplasmodial potential was assessed against Plasmodium falciparum (3D7) strain, and some of the synthesized compounds displayed promising antimalarial potency. On cytotoxicity evaluation using MTT cell viability assay, the most active candidate N-(4,6-dimethylpyridin-2-yl)-4-(4-(4-nitrophenoxy)methyl)-1H-[1,2,3]-triazol-1-yl)benzenesulfonamide ( 14 ; IC50 6.2 μg/mL) demonstrated CC50 7.5 μg/mL against human hepatocarcinoma (HUH-7) cells. 相似文献