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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Khadichakhan Rafikova Nil Ertekin Binbay Nermin Meriç Aygul Kerimkulova Alexey Zazybin Veysel Binbay Veysi Okumuş Cezmi Kayan Uğur Işik Nevin Arslan Murat Aydemir 《应用有机金属化学》2020,34(7):e5658
Four metal complexes, IL-OPPh2-Ru-p-cymene (3) , IL-OPPh2-Ru-benzene (4) , IL-OPPh2-Ir-Cp* (5) , IL-OPPh2-Rh-COD (6) , have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors. 相似文献
992.
Basma H. Amin Mohamed I. Abou-Dobara Mostafa A. Diab Essam A. Gomaa Mohammed A. El-Mogazy Adel Z. El-Sonbati Mohamed S. EL-Ghareib Mostafa A. Hussien Hanaa M. Salama 《应用有机金属化学》2020,34(8):e5689
A novel series of mixed-ligand complexes of 5,5′-{(1E,1E′)-1,4-phenelynebis(diazene-2,1-diyl)}bis(quinolin-8-ol) (H2L1) as a primary ligand and 4-aminoantipyrine(L2) as a secondary ligand with Mn(II) ion were prepared using two general formulae: [Mn2(H2L1)2(L2)2X4].4Cl (X = OH2( 1 ), ONO2−( 2 ), Cl=nil; OAc( 3 ), Cl = nil) and [Mn2(H2L1)(L2)2(O2SO2)2]( 4 ). Free ligands and their complexes were characterized. Electronic absorption spectra of the mixed-ligand complexes indicate a distorted octahedral geometry around the central metal ion, and the anions X− are in the axial positions for all compounds. The ligands behave in a neutral bidentate manner, through nitrogen atoms and oxygen atoms of the carbonyl group (L2), whereas H2L1 coordinated through nitrogen and OH groups as a neutral bidentate ligand. All complexes do not contain coordinated water molecules, but complex ( 1 ) contains four water molecules. The water molecules are removed in a single step. The complexes exhibited magnetic susceptibility corresponding to five unpaired electrons. The antimicrobial activity of the Mn(II) mixed-ligand complexes ( 1–4 ) against two gram-positive bacteria, three local gram-negative bacteria, and three fungi species was tested. Mn(II) mixed-ligand complex ( 2 ) exhibited significant antibacterial activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas sp. Mixed-ligand complex ( 2 ) exhibited a high potential cytotoxicity against the growth of human lung cancer cells. 相似文献
993.
Nonlinear Dynamics - This paper presents some dynamical and operational performance of shunt and permanent-magnet DC motors powered by lead–acid batteries for water pumping applications.... 相似文献
994.
P. Vaitheeswaran A. Udupa S. Sadasiva G. Subbarayan 《Continuum Mechanics and Thermodynamics》2020,32(4):987-1010
In this paper, the thermodynamic configurational force associated with a moving interface is used to derive the conditions for phase growth and nucleation in bodies with multiple diffusing species and arbitrary surface stress at the phase interface. First, the mass, momentum and energy balances are derived on the evolving phase interface. The thermodynamic conditions that result from free energy inequality at the interface are derived leading to the analytical form of the configurational force for bodies subject to mechanical loads, heat and multiple diffusing species. The derived second law condition naturally extends the Eshelby energy–momentum tensor to include species diffusion terms. The above second law restriction is then used to derive the condition for the growth of new phases in a body undergoing finite deformation subject to inhomogeneous as well as anisotropic interface stress, and multiple diffusing species. The growth conditions are derived in both current and reference configurations. The statistical temperature-dependent growth velocity is next derived using the Boltzmann distribution. The derived finite deformation form of growth requirement is simplified to obtain the small deformation diffusive void growth condition. Next, a general, finite deformation, arbitrary surface stress form of phase nucleation condition is derived by considering uncertainty in growth of a small nucleus. The probability of nucleation is shown to naturally depend on a theoretical estimate of critical volumetric energy density, which is directly related to the surface stress. The classical nucleation theory is shown to result from a simplified special case of the general criterion. As an application of the developed theory, the classical Blech electromigration experiment is simulated to estimate the critical energy density corresponding to the onset of electromigration voids at Al–TiN interface. 相似文献
995.
International Applied Mechanics - We present the exact solution to the problem of elastic plane bending of a layered composite beam of small width under normal loads linearly distributed over the... 相似文献
996.
997.
ABSTRACTNano-polycrystalline diamonds (NPDs) have become fundamental tools for cutting-edge X-ray absorption spectroscopy (XAS) studies at high P/T conditions that opened up new research directions by overcoming previous limitations. Indeed, NPDs yield a continuous and weak X-ray background signal which enables the collection of high-quality XAS data of materials compressed in diamond anvil cells. This is a critical advantage over the classically used single-crystal diamonds that generate strong parasitic signals (glitches) which render the analysis of XAS data in many cases impossible. In this contribution we give an overview of the impact and the scientific opportunities that NPDs opened up for extreme condition XAS spectroscopy at the European Synchrotron Radiation Facility and discuss future needs. 相似文献
998.
Efimenko I. A. Filimonova M. V. Churakov A. V. Ivanova N. A. Erofeeva O. S. Samsonova A. S. Podosinnikova T. S. Filimonov A. S. 《Russian Journal of Coordination Chemistry》2020,46(5):339-349
Russian Journal of Coordination Chemistry - Polymeric palladium complexes [(C5H12NO)(PdCl3)]n (I) and [(C10H16NO)2(Pd2Cl6)] (II) were synthesized for the first time and studied by X-ray... 相似文献
999.
Murinov Yu. I. Golubyatnikova L. G. Khisamutdinov R. A. Badamshin A. G. Dokichev V. A. 《Russian Journal of General Chemistry》2020,90(11):2048-2052
Russian Journal of General Chemistry - trans-Dichloropalladium(II) complexes with amino acid esters PdCl2L2 have been synthesized via selective hydrolytic cleavage of the nitrogen–carbon bond... 相似文献
1000.
Fedoseev S. V. Belikov M. Yu. Ershov O. V. Tafeenko V. A. 《Russian Journal of Organic Chemistry》2020,56(9):1540-1544
Russian Journal of Organic Chemistry - Heating of 2-halopyridine-3,4-dicarboxylic acids in propionic anhydride led to the formation of 4-halofuro[3,4-c]pyridine-1,3-diones as a result of... 相似文献