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Sakaue Shohei - - 2012
Two terbium ions in a triple-decker complex (Pc)Tb(Pc)Tb(T(p-OMe)PP) (Pc = phthalocyaninato, T(p-OMe)PP = tetra-p-methoxyphenylporphyrinato) have shown sharply different magnetic behaviours depending on symmetry of the coordination polyhedron. The fast quantum tunnelling relaxation process in a square-prismatic site has been revealed to be hindered by magnetic-dipolar coupling between the f-electronic systems.
Senkara-Barwijuk Elżbieta - - 2012
The interaction of mannose specific lectin (from Lens culinaris, LcL) with the carbohydrate moiety of carboxypeptidase Y (CaY) was studied using both atomic force microscope (AFM) and quartz crystal microbalance with dissipation monitoring (QCM-D). The AFM enables to determine the positions of energy barriers present in the energy landscape of ...
Reichelt Senta - - 2012
Hydrophilic poly(ethylene glycol)-based monoliths were synthesized in the spin-tip format for high-throughput applications via pulsed electron beam irradiation. Monoliths with a homogeneous porous structure and a total porosity of 69% were obtained. The cross-linked polymeric structure was further mechanically stabilized via the incorporation of silica nanoparticles. Amino-functionalization of the monoliths ...
Storchak Vyacheslav G - - 2012
We report muon spin rotation spectra in the narrow-gap semiconductors FeGa(3) and FeSb(2) consistent with a narrow band of small spin polarons (SPs). The characteristic sizes obtained for these SPs are R(FeGa(3)) ≈ 0.3-0.6 nm and R(FeSb (2)) ≈ 0.3 nm, respectively. Such SP states are expected to originate from the exchange correlations between localized and ...
Kang Stephen Dongmin - - 2012
Thermal transport at carbon nanotube (CNT) interfaces was investigated by characterizing the interfacial thermal conductance between metallic- or semiconducting-CNTs and three different surfactants. We thereby resolved a difference between metallic- and semiconducting-CNTs. CNT portions separated by their electronic type were prepared in aqueous suspensions. After slightly heating the CNTs dispersed ...
Shimizu Soji - - 2012
A β,β-sp(3)-hybridized subphthalocyanine analogue, dibenzosubtriazachlorin, was synthesized, and its significantly split Q band absorptions in longer and shorter wavelength regions relative to those of subphthalocyanines were revealed. The effect of benzo-annulation to a subtriazachlorin structure on the position of the split Q bands as well as the electronic structures was ...
Li Dan-Dan - - 2012
The palladium-catalyzed ortho-arylation of benzamides by aryl iodides has been demonstrated with the simplest amide CONH(2) as a directing group for the first time. This protocol can be applied to various benzamides and aryl iodides with both electron-donating and electron-withdrawing groups. In addition, the synthesized biphenyl-2-carboxamides can be further transformed ...
Tan Cen - - 2012
Imperfections that disrupt the sp<sup>2</sup> conjugation of graphene can alter its electrical, chemical, and mechanical properties. Here we report on the examination of monolayer CVD graphene imperfections using scanning electrochemical microscopy in the feedback mode. It was found that the sites with a large concentration of defects are ~1 order ...
Zhang Min - - 2012
The electron excitations of Single-Walled Silicon Nanotubes (SWSiNTs), with sp(2) and sp(3) hybridization, were studied using the localized-density-matrix (LDM) method with INDO/S parameters. Strong anisotropic characteristics of the dynamic polarizabilities were found for all the nanotubes. The transitional intensity along the tubular axis is much larger than that perpendicular to ...
Xu Cenke - - 2012
Motivated by recent experiments on material Ba_{3}NiSb_{2}O_{9}, we propose two novel spin liquid phases (A and B) for spin-1 systems on a triangular lattice. At the mean field level, both spin liquid phases have gapless fermionic spinon excitations with quadratic band touching; thus, in both phases the spin susceptibility and ...
Castelli Ivano E - - 2012
Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab initio study of such carbon-only materials, by computing their structure and stability, as well as their electronic, vibrational and magnetic properties. We adopt a fair compromise of microscopic realism with ...
Zhang Zhonghai - - 2012
In this paper, top-porous and bottom tubular TiO2 nanotubes (TiO2 NTs) loaded with palladium nanoparticles (Pd/TiO2 NTs) were fabricated as an electrode for an enhanced photoelectrocatalytic (PEC) activity toward organic dye decomposition. TiO2 NTs with a unique hierarchical top-porous and bottom-tubular structure were prepared by a facile two-step anodization method ...
Bode Matthias - - 2012
The principle of scanning tunneling microscopy, an imaging method with atomic resolution capability invented by Binnig and Rohrer in 1982, can be adapted for surface magnetism studies by using magnetic probe tips. The contrast mechanism of this so-called spin-polarized scanning tunneling microscopy, or SP-STM, relies on the tunneling magneto-resistance effect, ...
Li Yongliang - - 2011
Birnessite flower-like and α-type tubular MnO(2) nanostructures were selectively synthesized through simple decomposition of KMnO(4) under hydrochloric acid condition by controlling reaction temperature using a microwave-assisted hydrothermal method. The as-prepared samples were characterized in detail by various techniques including X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, high-resolution ...
Fisher Lauren S - - 2011
Electron crystallography plays a key role in the structural biology of integral membrane proteins (IMPs) by offering one of the most direct means of providing insight into the functional state of these molecular machines in their lipid-associated forms, and also has the potential to facilitate examination of physiologically relevant transitional ...
Lao Ka-Un - - 2011
Density functional theory has been used to calculate the thermodynamic properties and molecular orbitals of pillar[n]quinones. Pillar[n]quinones are expected to be effective electron acceptors and the ability to accept more than one electron increases with the size of the interior cavity. Pillar[5]quinone and pillar[7]quinone show a great intramolecular charge transfer ...
Gao Rui - - 2011
In this paper, the interface modification effects of 4-tertbutylpyridine (TBP), especially the interaction with dye molecules, were discussed. The results of FTIR showed that TBP interacted with dye molecules, in addition to its interaction with the TiO(2) film. Reaction between N3 and TBP by the interaction force of the H ...
Blanco-Rodríguez Ana María - - 2011
The [Re(I)(CO)(3)(4,7-dimethyl-1,10-phenanthroline)(histidine-124)(tryptophan-122)] complex, denoted [Re(I)(dmp)(W122)], of Pseudomonas aeruginosa azurin behaves as a single photoactive unit that triggers very fast electron transfer (ET) from a distant (2 nm) Cu(I) center in the protein. Analysis of time-resolved (ps-μs) IR spectroscopic and kinetics data collected on [Re(I)(dmp)(W122)AzM] (in which M=Zn(II), Cu(II), Cu(I); Az=azurin) ...
Yan Xaodong - - 2011
A simple two-steps method has been successfully developed to synthesize ZnO nanotubes. The alkaline etching process was investigated in detail using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The formation of ZnO nanotube structures was due to the preferential dissolution of the defect-rich top (polar) faces. Cathodoluminescence (CL) ...
Brożek-Mucha Zuzanna - - 2011
A study of the chemical contents and sizes of gunshot residue originating from 9×18mm PM ammunition, depositing in the vicinity of the shooting person was performed by means of scanning electron microscopy and energy dispersive X-ray spectrometry. Samples of the residue were collected from targets placed at various distances in ...
Roy Choudhury Samrat - - 2011
Surface-modified sulfur nanoparticles (SNPs) of two different sizes were prepared via a modified liquid-phase precipitation method, using sodium polysulfide and ammonium polysulfide as starting material and polyethylene glycol-400 (PEG-400) as the surface stabilizing agent. Surface topology, size distribution, surface modification of SNPs with PEG-400, quantitative analysis for the presence of ...
Castelletto V - - 2011
The dipeptide l-carnosine has a number of important biological properties. Here, we explore the effect of attachment of a bulky hydrophobic aromatic unit, Fmoc [N-(fluorenyl-9-methoxycarbonyl)] on the self-assembly of Fmoc-l-carnosine, i.e., Fmoc-β-alanine-histidine (Fmoc-βAH). It is shown that Fmoc-βAH forms well-defined amyloid fibrils containing β sheets above a critical aggregation concentration, ...
Xiong Zhigang - - 2011
Previously, it was found that reduced graphene oxide (RGO) can degrade rhodamine B (RhB) under visible-light irradiation, but with an extraordinarily slow rate. It was also found that modification of RGO with gold nanoparticles can dramatically accelerate the photoreaction rate. Herein, we describe the preparation and photocatalytic properties of copper-ion-modified RGO ...
Xiong Zhigang - - 2011
Previously, it was found that reduced graphene oxide (RGO) can degrade rhodamine B (RhB) under visible-light irradiation, but with an extraordinarily slow rate. It was also found that modification of RGO with gold nanoparticles can dramatically accelerate the photoreaction rate. Herein, we describe the preparation and photocatalytic properties of copper-ion-modified RGO ...
Lebedkin Sergei - - 2011
We describe the simple modification of a confocal Raman imaging microscope to incorporate two ultra-narrow holographic notch filters. The modified microscope rejects the laser excitation line (Rayleigh peak) by a discrimination factor of ∼10(11) and allows simultaneous measurements of Stokes/anti-Stokes Raman shifts as close as ∼10/20 cm(-1) to the Rayleigh ...
Costa Pedro M F J - - 2011
Understanding resistive (or Joule) heating in fundamental nanoelectronic blocks, such as carbon nanotubes, remains a major challenge, particularly in regard to their structural and thermal variations during prolonged periods of electrical stress. Here we show real-time imaging of the associated effects of Joule heating in the channel of carbon nanotube ...
Deng Shunliu - - 2011
Covalent chemistry typically occurs randomly on the graphene lattice of a carbon nanotube because electrons are delocalized over thousands of atomic sites, and rapidly destroys the electrical and optical properties of the nanotube. Here we show that the Billups-Birch reductive alkylation, a variant of the nearly century-old Birch reduction, occurs ...
Park Yeunsoo - - 2010
Abstract Low-energy electrons (LEE) induce single- and double-strand breaks in DNA. To investigate the mechanism of LEE-induced DNA damage, nucleotides and short oligonucleotide were irradiated with monoenergetic electrons in the solid state and the modifications were observed by chemical analyses. With 10 eV electrons and TpTpT as the target, approximately one-third ...
Park Yeunsoo - - 2011
Low-energy electrons (LEE) induce single- and double-strand breaks in DNA. To investigate the mechanism of LEE-induced DNA damage, nucleotides and short oligonucleotide were irradiated with monoenergetic electrons in the solid state and the modifications were observed by chemical analyses. With 10 eV electrons and TpTpT as the target, approximately one-third ...
Wang Shukuan - - 2010
The electronic properties of four metallofullerenol samples (La@C82(OH)32, La@C82(OH)24, La@C82(OH)18, La@C82(OH)12) and La@C82 were investigated by synchrotron radiation photoelectron emission spectra (PES). A new emission peak with binding energy of 13.9 eV, which is attributed to La 5d orbitals coupling with nanocage orbitals, is observed in PES of La@C82 for ...
Rockafellow Erin M - - 2010
This work describes the preparation of a selenium-modified TiO(2) photocatalyst and a preliminary evaluation of its photocatalytic activity. Se-TiO(2) displayed greater visible absorption than undoped TiO(2) and was still capable of degrading quinoline at a slightly faster rate than undoped TiO(2) under UV light. Se-TiO(2) was also able to degrade ...
Aggarwal M M - - 2010
The contribution of B meson decays to nonphotonic electrons, which are mainly produced by the semileptonic decays of heavy-flavor mesons, in p + p collisions at √s=200  GeV has been measured using azimuthal correlations between nonphotonic electrons and hadrons. The extracted B decay contribution is approximately 50% at a transverse momentum ...
Brückner Angelika - - 2010
Electron Paramagnetic Resonance (EPR) offers widespread opportunities for monitoring catalytically relevant species that contain unpaired electrons under conditions close to those of heterogeneous catalytic gas and liquid phase reactions. In this tutorial review, after introducing basic theoretical and experimental principles of the technique, selected examples of typical applications are discussed ...
Baranov Pavel G - - 2010
It is shown that high-frequency electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) spectroscopy are excellent tools for the investigation of the electronic properties of semiconductor quantum dots (QDs). The great attractions of these techniques are that, in contrast to optical methods, they allow the identification of the dopants ...
Zhu Han - - 2010
We report the observation of a resonance in the microwave spectra of the real diagonal conductivities of a two-dimensional electron system within a range of ∼ ± 0.015 from filling factor ν = 1/3. The resonance is remarkably similar to resonances previously observed near integer ν, and is interpreted as ...
Gross Noam - - 2010
We investigate three-body recombination loss across a Feshbach resonance in a gas of ultracold 7Li atoms prepared in the absolute ground state and perform a comparison with previously reported results of a different nuclear-spin state [N. Gross, Phys. Rev. Lett. 103, 163202 (2009)]. We extend the previously reported universality in ...
De Groot Judith I M - - 2010
We examined factors underlying people's willingness to take action in favor of or against nuclear energy from a moral perspective. We conducted a questionnaire study among a sample of the Dutch population (N = 123). As expected, perceptions of risks and benefits were related to personal norms (PN), that is, ...
Mohammady M H - - 2010
We investigate electron paramagnetic resonance spectra of bismuth-doped silicon, at intermediate magnetic fields B≃0.1-0.6  T, theoretically and experimentally (with 9.7 GHz X-band spectra). We identify a previously unexplored regime of "cancellation resonances," where a component of the hyperfine coupling is resonant with the external field. We show that this regime has experimentally ...
Drew Simon C - - 2010
Spin Hamiltonian parameters for the neutral trigonal-prismatic Tc(abt)(3) and Re(abt)(3) chelates (abt = o-aminobenzenethiol) are calculated using relativistic density functional theory at the all-electron level. The small magnitude of the calculated g shifts and metal hyperfine interactions is in excellent agreement with previous experimental predictions based upon a ligand-centered ground-state ...
Wei Yu-Ling - - 2010
Visible light active photocatalysts were successfully prepared by incorporating chromium into anatase TiO2 at two Cr/Ti atomic ratios (0.03% and 0.11%) by the use of a modified sol-gel process. Results show that the size of the chromium modified TiO2 particles is approximately 14-25 nm. As indicated by diffuse reflectance ultra ...
Kothe Gerd - - 2010
The unique physical properties of photoexcited triplet states have been explored in numerous spectroscopic studies employing electron paramagnetic resonance (EPR). So far, however, no quantum interference effects were found in these systems in the presence of a magnetic field. In this study, we report the successful EPR detection of nuclear ...
Rakvin Boris - - 2010
Dynamic properties of the first stable l-alanine radical, SAR1, induced by gamma-irradiation of l-alanine crystals, have been investigated by the electron nuclear double resonance technique (ENDOR). The study focuses on the dynamic properties of the alpha-proton hyperfine splitting in the temperature range from 180 to 320 K. In this region ...
Kim Nak-Kyoon - - 2010
Divalent metal (Mg(2+)) ion-dependent folding of the hammerhead ribozyme from Schistosoma mansoni was monitored with double electron-electron resonance (DEER) pulsed electron paramagnetic resonance spectroscopy by measuring nanometer-scale distances between paramagnetic spin-labels attached to the RNA. DEER measurements detect global folding of the ribozyme with excellent agreement between predictions from experimental, ...
Reilly D J - - 2010
The influence of gate-controlled two-electron exchange on the relaxation of nuclear polarization in small ensembles (N∼10(6)) of nuclear spins is examined in a GaAs double quantum dot system. Waiting in the (2,0) charge configuration, which has large exchange splitting, reduces the nuclear diffusion rate compared to that of the (1,1) ...
Macholl Sven - - 2010
The objective of this study is to investigate if trityl biradicals could lead to more efficient dynamic nuclear polarization (DNP) for low gamma nuclear spins at low temperature (approximately 1 K) than a trityl monoradical. Three novel trityl biradicals of different size are synthesized, characterized and employed for hyperpolarization of ...
Pattier Bruno - - 2010
EPR investigations of the photoreduction of Ti(4+) into Ti(3+) under UV irradiation were carried out on three titanium-based materials for which the initial concentration of Ti(4+) was defined in the ternary phase diagram (TiOCl(2), H(2)O, DMF). The kinetics of this photoreduction was monitored at 200 K and related to the ...
Sigle W - - 2010
Using energy-filtering transmission electron microscopy we observe localized plasmon resonances in nanoholes of silver. We find two resonances that are typical for single, isolated holes. A comparison with calculations based on the discrete dipole approximation shows that these are dipolar and quadrupolar resonances. In case of the close vicinity of ...
Quine Richard W - - 2010
Experimental data obtained with an electron paramagnetic resonance (EPR) rapid scan spectrometer were translated through the reverse transfer functions of the spectrometer hardware to the sample position. Separately, theoretical calculations were performed to predict signal and noise amplitudes at the sample position for specified experimental conditions. A comparison was then ...
Auer Benjamin - - 2010
An approximation for treating multiple quantum nuclei within the nuclear-electronic orbital (NEO) framework for molecular systems is presented. In the approximation to NEO-Hartree-Fock, the nuclear wave function is represented by a Hartree product rather than a Slater determinant, corresponding to the neglect of the nuclear exchange interactions. In the approximation ...
Benial A Milton Franklin - - 2010
Overhauser-enhanced magnetic resonance imaging (OMRI) studies of a membrane-permeable nitroxyl spin probe, (2)H-enriched 3-methoxycarbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (MC-PROXYL), used in simultaneous molecular imaging is reported. Phantom imaging was performed with liposomal solutions of MC-PROXYL at varying spin probe and liposome concentrations using a field-cycle mode, custom-built OMRI scanner. Dynamic nuclear polarization (DNP) spectra ...
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