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排序方式: 共有285条查询结果,搜索用时 93 毫秒
281.
Yao Yuan Dr. Samira Adimi Dr. Xuyun Guo Dr. Tiju Thomas Dr. Ye Zhu Dr. Haichuan Guo G. Sudha Priyanga Pilsun Yoo Prof. Jiacheng Wang Prof. Jian Chen Dr. Peilin Liao Prof. J. Paul Attfield Prof. Minghui Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(41):18192-18197
The oxygen evolution reaction (OER) is key to renewable energy technologies such as water electrolysis and metal–air batteries. However, the multiple steps associated with proton-coupled electron transfer result in sluggish OER kinetics and catalysts are required. Here we demonstrate that a novel nitride, Ni2Mo3N, is a highly active OER catalyst that outperforms the benchmark material RuO2. Ni2Mo3N exhibits a current density of 10 mA cm−2 at a nominal overpotential of 270 mV in 0.1 m KOH with outstanding catalytic cyclability and durability. Structural characterization and computational studies reveal that the excellent activity stems from the formation of a surface-oxide-rich activation layer (SOAL). Secondary Mo atoms on the surface act as electron pumps that stabilize oxygen-containing species and facilitate the continuity of the reactions. This discovery will stimulate the further development of ternary nitrides with oxide surface layers as efficient OER catalysts for electrochemical energy devices. 相似文献
282.
Samira Mehravar Shohreh Fatemi Masaharu Komiyama 《Surface and interface analysis : SIA》2020,52(9):547-552
Nickel supported on reduced graphene oxide was synthesized by chemical vapor deposition technique. The crystal structure and magnetic properties of the prepared sample were studied by means of Raman spectrometry, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), inductively coupled plasma optical emission spectrometry (ICP-OES), and vibrating sample magnetometry (VSM). The result of Raman spectroscopy revealed the structure of few-layer graphene as the support for Ni nanoparticles. XP spectrum confirmed the presence of metallic Ni on the a few-layer graphene surface. TE micrograph showed that the nickel nanoparticles were sphere shaped and the mean particle size is about 20 nm deposited on the reduced graphene oxide. The magnetic study showed the ferromagnetic behavior of 3.2 wt% nickel over reduced graphene oxide at room temperature. 相似文献
283.
Mitra Ghassemzadeh Samira BahemmatMasoumeh Tabatabaee Salameh NassiriBernhard Neumüller 《Polyhedron》2011,30(11):1760-1766
The synthesis and characterization of three new palladium(II) complexes of 4-amino-6-ethyl-1,2,4-triazine-3-thion-5-one (AETTO, H3L), [PdCl2(H3L)]·H2O (1), [Pd2Cl2(H2L)(PPh3)3]NO3·2CH3CN (2) and [Pd(HL)(PPh3)2] (3), are reported. All the synthesized compounds are air-stable and were characterized by elemental analyses, IR, NMR spectroscopy and mass spectrometry. In addition, the molecular structures of the complexes have been determined by X-ray single crystal diffraction. On the basis of the crystallographic data, the neutral ligand in 1 and the deprotonated ligands in 2 and 3 act as bidentate NS donors. The singly deprotonated ligand in 2 acts as a bridging agent between two metal centers in the binuclear PdII-complex. 相似文献
284.
Sadegh Salehzadeh Farshid Hajibabaei Neda Hosseinpour Moghadam Samira Sharifinia Sadegh Khazalpour Reza Golbedaghi 《Journal of fluorescence》2018,28(1):195-206
In the present work, the interaction of Isoxsuprine (ISX) with Calf thymus DNA (ct-DNA) under physiological conditions (Tris–HCl buffer of pH 7.4) was investigated by using electronic absorption, circular dichroism, viscosity, electrochemical studies, fluorescence techniques, salt effect studies and computational studies. Competitive fluorimetric studies with Hoechst 33258 have shown that ISX exhibit the ability to displace the DNA-bound Hoechst 33258, indicating that it binds to ct-DNA in strong competition with Hoechst 33258 for the minor groove binding. Furthermore, the resulting data showed that ISX cannot displace methylene blue or acridine orange, which are the common intercalator molecules. The viscosity of ct-DNA solution was almost unchanged on addition of ISX and circular dichroism (CD) spectra of ct-DNA showed small changes in the presence of ISX which is in agreement with groove binding mode of interaction. Thus all above studies showed that the ISX drug binds to ct-DNA in a groove binding mode.The salt-effect studies showed the non-electrostatic nature of binding of ISX to ct-DNA. Moreover, molecular docking results support the above experimental data and suggest that ISX prefers to bind on the minor groove of ct-DNA. 相似文献
285.
Klaus Tauer Samira Nozari A. M. Imroz Ali Steffen Kozempel 《Macromolecular rapid communications》2005,26(15):1228-1232
Summary: Optical absorption measurements are used for the first time to investigate the uptake of pure organic solvents or solutions by latex particles. Sorption into glassy polymer particles is a two‐stage process with distinctly different characteristic times, which reflects that an initial softening of the outer particle layer facilitates further uptake. The sorption of solutions containing highly water‐insoluble compounds allows the preparation of composite nanoparticles, which are hardly accessible by other routes.