نتایج جستجو برای: metal cluster
تعداد نتایج: 395377 فیلتر نتایج به سال:
We use classical molecular dynamics simulations to investigate temperature control of unsupported clusters using a noble gas atmosphere. The simulations are performed using a many-body interaction scheme for the intra-cluster potential, while a pairwise Lennard-Jones potential is used to model the interaction between the noble gas and the clusters. In order to isolate different parameters deter...
This investigation, following our recent report on the one-pot hemi-micellar interfacial synthesis of Janus gold nanoclusters and the inter-cluster electron coupling establishing insulator-metal transition in the oriented Janus monolayers [Langmuir, 2010, 26(17), 14047], was to fabricate modified electrodes for sensing dopamine, the neurotransmitter. With a detection limit in the sub-nanomolar ...
Since the first proposal that fullerenes are capable of hosting atoms, ions, or clusters by the late Smalley in 1985, tremendous examples of endohedral metallofullerenes (EMFs) have been reported. Breaking the dogma that monometallofullerenes (mono-EMFs) always exist in the form of M@C2n while clusterfullerenes always require multiple (two to four) metal cations to stabilize a cluster that is u...
Using a gradient-corrected density functional method, we studied computationally how single impurity atoms affect the structure and the properties of a Ni4 cluster. H and O atoms coordinate at a Ni-Ni bond, inducing small changes to the structure of bare Ni4 which is essentially a tetrahedron. For a C impurity, we found three stable structures at a Ni4 cluster. In the most stable geometry, the ...
We report on high resolution Echelle spectroscopy of 20 giant stars in the Galactic old open clusters NGC 6791 obtained with Hydra at the WIYN telescope. High precision radial velocity allow us to isolate 15 bona fide cluster members. From 10 of them we derive a global [M/H]=+0.39±0.05. We therefore confirm that NGC 6791 is extremely metal rich, exhibits a few marginally sub-solar abundance rat...
When Neurospora crassa is grown in the presence of Cu(II) ions, it accumulates the metal with the concomitant synthesis of a low molecular weight copper-binding protein. The molecule binds 6 g-atom of copper per mole protein (Mr = 2200) and shows a striking sequence homology to the zinc- and cadmium-binding vertebrate metallothioneins. Absorption, circular dichroism, and electron paramagnetic r...
The structure of the oxygen-evolving complex of photosystem II, which contains a cubane-like metal-oxo cluster incorporating four manganese(III,IV) cations, along with a calcium cation, has focussed attention on synthetic analogues of this cluster. Despite this activity, there are relatively few structurally characterised coordination clusters with this combination of metal cations. The calixar...
Formation process of single-walled carbon nanotubes by the catalytic chemical vapor deposition method is studied by molecular dynamics simulation. We start the calculation with randomly distributed carbon-source molecules and a nickel cluster to investigate the metal-catalyzed growth of a cap-structure of a nanotube. When the catalytic cluster reaches saturation with carbon atoms, hexagonal net...
The nucleation and growth of Co clusters on vacuum-annealed (reduced) and oxidized TiO2(110) have been studied by scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and density function theory (DFT) calculations. On vacuum-annealed TiO2(110), the Co clusters grow as three-dimensional islands at coverages between 0.02 and 0.25 ML, but the cluster heights range from ∼3 t...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید