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排序方式: 共有290条查询结果,搜索用时 15 毫秒
61.
62.
Rong Kou Yuyan Shao Donghai Wang Mark H. Engelhard Ja Hun Kwak Jun Wang Vilayanur V. Viswanathan Chongmin Wang Yuehe Lin Yong Wang Ilhan A. Aksay Jun Liu 《Electrochemistry communications》2009,11(5):954-957
Electrocatalysis of oxygen reduction using Pt nanoparticles supported on functionalized graphene sheets (FGSs) was studied. FGSs were prepared by thermal expansion of graphite oxide. Pt nanoparticles with average diameter of 2 nm were uniformly loaded on FGSs by impregnation methods. Pt-FGS showed a higher electrochemical surface area and oxygen reduction activity with improved stability as compared with the commercial catalyst. Transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical characterization suggest that the improved performance of Pt-FGS can be attributed to smaller particle size and less aggregation of Pt nanoparticles on the functionalized graphene sheets. 相似文献
63.
Wail Al Zoubi Abbas Ali Salih Al‐Hamdani I Putu Widiantara Rehab Ghalib Hamoodah Young Gun Ko 《Journal of Physical Organic Chemistry》2017,30(12)
New ligand 4‐((2‐Hydroxy1‐naphthyl) methylene amino)‐1.5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one (HL) was synthesized from the reaction of 2‐hydroxy‐1‐naphthaldehyde and 4‐aminophenaz one. A complexes of this ligand [VO(II)(HL)(SO4)], [Pt(IV)(L)Cl3], [Re(V)(L)Cl3]Cl, and [M(II)(L)Cl] (M═Pd(II), Ni(II), Cu(II)) were synthesized. The resulted compounds were characterized by IR, NMR (1H and 13C), mass spectrometry, element analysis, and UV‐Vis spectroscopy. Additionally, the spectroscopic studies revealed octahedral geometries for the Re(V), Pt(IV) complexes, and square pyramidal for VO(II), square planar for Pd(II) complex, and tetrahedral for the Ni(II) and Cu(II) complexes. Thermodynamic parameters (ΔE*, ΔH*, ΔS*, ΔG*, and K) were calculated using from the TGA curve Coats‐Red fern method. Therefore, hyper Chem‐8 program has been used to predict structural geometries of compounds in the gas phase. Finally, the synthesized Schiff base and its metal complexes were screened for their biological activity against bacterial species, 2 Gram‐positive bacteria (Bacillus subtilis and Staphylococcus aureus) and 2 Gram‐negative bacteria (Escherichia coli and Pseudomonas aeruginosa). 相似文献
64.
Esra Ilhan‐Ayisigi Pelin Saglam‐Metiner Giuliana Manzi Katharine Giannasi Wim van Hoeve Ozlem Yesil‐Celiktas 《Macromolecular bioscience》2020,20(6)
In this study, the neoplastic drug frequently used in the treatment of lung cancer, carboplatin is loaded to microbubbles via a microfluidic platform. In order to increase the drug loading capacity of microbubbles, carboplatin is encapsulated into alginate polymer layer. The phospholipid microbubbles (MBs) are synthesized by MicroSphere Creator, which is connected with T‐junction and micromixer for the treatment with CaCl2 solution to provide gelation of the alginate coated phospholipid microbubbles (AMBs). The carboplatin loaded alginate coated phospholipid microbubbles (CAMBs) result in 12.2 ± 0.21 µm mean size, obtained by mixing with 0.05% CaCl2 using T‐junction. The cytotoxic activities of the synthesized MBs, AMBs, and CAMBs are also investigated with the 3‐(4,5‐Dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) (MTT) and live/dead fluorescent dying assays in the A549 and BEAS‐2B cell lines. The one‐step microfluidic coating of lipid microbubbles with natural alginate polymer appears to be a promising strategy for enhanced drug reservoir properties. 相似文献
65.
Salih S. Al-Juaid Colin Eaborn Paul D. Lickiss J. David Smith Kayumars Tavakkoli Alexander D. Webb 《Journal of organometallic chemistry》1996,510(1-2):143-151
Mercury compounds of the types HgR1R (R1 = C(SiMe3)3; R = Me, iPr, Bu, tBu or Ph) and HgR2R(R2 = C(SiMe2Ph)3; R = Me, Bu, CH2Ph or Ph) have been prepared. Those containing R1 were made by reactions of the bromides HgR1Br with the Grignard reagents MgRX, and those containing R2 by reaction of HgR2Cl with LiR or, for R = CH2Ph, with Mg(CH2Ph)Cl. Replacement of one R group in HgR2 by the bulky R1 or R2 group leads to a large increase in thermal stability, a marked shift in the 199Hg resonance to lower frequency and an increase in the coupling constant 1J(13C---199Hg) for the Hg---R bond. The compound HgR2Cl does not react further with LiR2 in tetrahydrofuran, but with LiR1 gives HgR1R2; the arrangement of the SiMe2Ph groups in the latter in solution in CH2C12 at low temperature appears to be different from that in the solid. 相似文献
66.
Frankamp BL Uzun O Ilhan F Boal AK Rotello VM 《Journal of the American Chemical Society》2002,124(6):892-893
Polystyrene-based diblock copolymers, featuring diaminotriazine functionality on one of the blocks were used to assemble complementary uracil-functionalized nanoparticles into micellar aggregates. The size of these self-assembled aggregates was controlled by block length, as determined in solution (using dynamic light scattering), and in thin films (using transmission electron microscopy). 相似文献
67.
An atomic absorption spectrophotometric method for the microdetermination of chlorine or bromine in organic compounds is described; it is based on oxygen flask combustion to yield chloride or bromide, which is then reacted with an excess of solid silver chromate, followed by collection of the combined unreacted silver chromate and chloride or bromide preipitate and AAS determination of the free chromate (equivalent of the chloride or bromide originally present) at 358.2 nm. The method was applied satisfactorily to a wide range of chlorine or bromine containing organic compounds with an average absolute error of ± 0.23 and a coefficient of variation (seven determinations) of better than 2%. 相似文献
68.
Salih Ilhan Hamdi Temel Recep Ziyadanogullari Memet Sekerci 《Transition Metal Chemistry》2007,32(5):584-590
A new macrocyclic ligand, 1,3,5-triaza-2,4:7,8:15,16-tribenzo-9,15-dioxacycloheptadeca-1,5-diene (L) was synthesized by reaction
of 2,6-diaminopyridine with 1,4-bis(2-carboxyaldehydephenoxy)butane. Then, its CuII, NiII, PbII, CoIII and LaIII complexes were synthesized by the template effect by reaction of 2,6-diaminopyridine and 1,4-bis (2-carboxyaldehydephenoxy)butane and Cu(NO3)2 · 3H2O, Ni(NO3)2 · 6H2O, Pb(NO3)2, Co(NO3)2 · 6H2O, La (NO3)3 · 6H2O, respectively. The ligand and its metal complexes were characterized by elemental analysis, IR, 1H- and 13C-n.m.r., UV-vis spectra, magnetic susceptibility, thermal gravimetric analysis, conductivity measurements and mass spectra.
All complexes are diamagnetic and the CuII complex is binuclear. The CoII complex was oxidised to CoIII. 相似文献
69.
Telhat??zdo?anEmail author Metin?Orbay Salih?De?irmenci 《Journal of mathematical chemistry》2005,37(1):27-36
Using the definition of STOs in terms of BTOs, we have presented analytical formula for two-center overlap integrals. The obtained formula contains generalized binomial coefficients and Mulliken integrals Ak and Bk. Taking into account the recent advances on the efficient calculation of Mulliken integrals (Harris, Int. J. Quantum Chem., 100 (2004) 142), we have obtained many more satisfactory results for two-center overlap integrals, for arbitrary quantum numbers, scaling parameters, and location of atomic orbitals.PACS No: 31.15.+qAMS Subject Classification: 81V55, 81–08 相似文献
70.
Hamdi Temel Hüseyin Alp Salih İlhan Berrin Ziyadanoğulları İsmail Yılmaz 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1199-1209
Summary. La(III), Cu(II), Ni(II), and Zn(II) metal complexes with a novel quadridentate Schiff base derived from 1,7-bis(2-formylphenyl)-1,4,7-trioxaheptane and 2-aminothiophenol were synthesized and characterized by
microanalytical data, elemental analysis, magnetic measurements, 1H NMR, 13C NMR, UV-Vis, IR, mass spectra, cyclic voltammetric and conductance measurements. The extractability of divalent cations
was evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. The highest extraction percentage of Cu2+ and Ni2+ showed pH 7.0 and 6.4. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) and nickel(II)
from the aqueous phase to the organic phase. 相似文献