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303.
Mohammad Madani Mahdi Fathizadeh Yasir Khan Ahmet Yildirim 《Mathematical and Computer Modelling》2011,53(9-10):1937-1945
In this paper, a Laplace homotopy perturbation method is employed for solving one-dimensional non-homogeneous partial differential equations with a variable coefficient. This method is a combination of the Laplace transform and the Homotopy Perturbation Method (LHPM). LHPM presents an accurate methodology to solve non-homogeneous partial differential equations with a variable coefficient. The aim of using the Laplace transform is to overcome the deficiency that is mainly caused by unsatisfied conditions in other semi-analytical methods such as HPM, VIM, and ADM. The approximate solutions obtained by means of LHPM in a wide range of the problem’s domain were compared with those results obtained from the actual solutions, the Homotopy Perturbation Method (HPM) and the finite element method. The comparison shows a precise agreement between the results, and introduces this new method as an applicable one which it needs fewer computations and is much easier and more convenient than others, so it can be widely used in engineering too. 相似文献
304.
Sodium magnesium amidoborane: the first mixed-metal amidoborane 总被引:1,自引:0,他引:1
Wu H Zhou W Pinkerton FE Meyer MS Yao Q Gadipelli S Udovic TJ Yildirim T Rush JJ 《Chemical communications (Cambridge, England)》2011,47(14):4102-4104
The first example of a mixed-metal amidoborane Na(2)Mg(NH(2)BH(3))(4) has been successfully synthesized. It forms an ordered arrangement in cation coordinations, i.e., Mg(2+) bonds solely to N(-) and Na(+) coordinates only with BH(3). Compared to ammonia borane and monometallic amidoboranes, Na(2)Mg(NH(2)BH(3))(4) can release 8.4 wt% pure hydrogen with significantly less toxic gases. 相似文献
305.
Ş. Hakan Üngören Mustafa Saçmacı Cengiz Arıcı Ertan Şahin Taner Arslan Fatma Kandemirli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2877-2890
Novel alkyl substituted 3-(4-benzoyl-1,5-diphenyl-2,3-dihydro-1H-pyrazol-3-yl)-3-oxo-2-(triphenylphosphoranylidene) propanoates (3) were synthesized from 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonylchloride (1) and alkyl (triphenylphosphoranylidene) acetates (2a–b). The synthesized compounds were characterized by elemental analysis, spectroscopic studies (3a–b), and single crystal X-ray diffraction (3a). The mechanism of the reaction between (1) and (2a) was studied by AM1, and the geometrical parameters of the studied molecules were also carried out in B3LYP methods with the standard 6–31G (d,p) basis set. NBO analysis were studied for 1 and 2a B3LYP methods with the standard 6–31G (d,p) basis set. 相似文献
306.
Sara Mahdjoub Muhammet Yildirim Sihem Lakehal Houssem Boulebd Abdelmadjid Debache 《合成通讯》2013,43(18):2366-2381
AbstractA simple and efficient protocol for one-pot three-component synthesis of structurally diverse dialkyl 2-amino-3-cyano-4H-chromen-4-ylphosphonates from the condensation of salicylaldehydes, malononitrile, and trialkyl phosphite using silver nanoparticles as catalyst in ethanol at reflux has been developed. Selected new compounds were evaluated for their antioxidant activity by free radical screening using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Among the compounds employed, 5a, 5?b, and 5?h showed promising DPPH radical scavenging activities compared to the experimental standards at low concentration (100?µg/mL) after 24?h incubation. 相似文献
307.
Two vic-dioxime ligands, N-(4-benzylpiperazine-1-yl) p-tolylglyoxime (L1H2) and N,N′-bis(4-benzylpiperazine-1-yl) glyoxime (L2H2), containing piperazine moieties were synthesized, and their Ni(II), Cu(II), Co(II) and Zn(II) complexes were obtained. The ligands were characterized by elemental analysis, Fourier transform–infrared (FT-IR), ultraviolet–visible NMR (1H, 13C, and heteronuclear multiple-bond correlation), and electrospray ionization (ESI) mass spectrometry. The isolated complexes were characterized by a combination of elemental analysis, IR, UV-vis, and ESI mass spectrometry and in the case of Ni(II) and Zn(II) complexes by 1H and 13C NMR spectroscopy. The electrochemical behaviors of the ligands and their complexes were studied by cyclic voltammetry (CV) in dimethylsulfoxide solution containing tetrabutylammoniumtetrafluoroborate (TBATFB). The antibacterial activity was also studied against S. aureus ATCC 25923, S. aureus ATCC 29213, S. mutans RSHM 676, E. faecalis ATCC 29212, E. coli ATCC 25922, and P. aeruginosa ATCC 27853. The antimicrobial test results indicated that all the compounds have good antibacterial activity against P. auriginosa ATCC 27853 bacteria and were as effective as ampicilin. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献
308.
Yildirim O Yilmaz MD Reinhoudt DN Blank DH Rijnders G Huskens J 《Langmuir : the ACS journal of surfaces and colloids》2011,27(16):9890-9894
Alkylphosphate self-assembled monolayers (SAMs) were prepared on Nb-doped SrTiO(3) (Nb-STO) conducting metal oxide substrates. Unlike thiols on gold, the alkylphosphate SAMs on Nb-STO exhibited an electrochemical stability over a wide voltage range from -2 to 2 V. Cyclic voltammetry showed that the SAM modification inhibited the electrochemical activity of the underlying conducting substrate with an efficiency dependent on the chain length. Impedance spectroscopy showed that SAM-modified Nb-STO substrates have a significantly higher resistance than bare substrates. 相似文献
309.
Dikici Tuncay Demirci Selim Tünçay Mehmet Masum Yildirim Bercem Kiran Kaya Nusret 《Journal of Sol-Gel Science and Technology》2021,98(3):637-638
Journal of Sol-Gel Science and Technology - 相似文献