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Surinova Silvia - - 2013
Targeted proteomics based on selected reaction monitoring (SRM) mass spectrometry is commonly used for accurate and reproducible quantification of protein analytes in complex biological mixtures. Strictly hypothesis-driven, SRM assays quantify each targeted protein by collecting measurements on its peptide fragment ions, called transitions. To achieve sensitive and accurate quantitative results, ...
Bolatto Alberto D - - 2013
The under-abundance of very massive galaxies in the Universe is frequently attributed to the effect of galactic winds. Although ionized galactic winds are readily observable, most of the expelled mass (that is, the total mass flowing out from the nuclear region) is likely to be in atomic and molecular phases ...
Kaltenbrunner Martin - - 2013
Electronic devices have advanced from their heavy, bulky origins to become smart, mobile appliances. Nevertheless, they remain rigid, which precludes their intimate integration into everyday life. Flexible, textile and stretchable electronics are emerging research areas and may yield mainstream technologies. Rollable and unbreakable backplanes with amorphous silicon field-effect transistors on ...
Gulev Sergey K - - 2013
Nearly 50 years ago Bjerknes suggested that the character of large-scale air-sea interaction over the mid-latitude North Atlantic Ocean differs with timescales: the atmosphere was thought to drive directly most short-term--interannual--sea surface temperature (SST) variability, and the ocean to contribute significantly to long-term--multidecadal--SST and potentially atmospheric variability. Although the conjecture ...
Kim Eunjoo - - 2013
Here, we report a seeded growth protocol for synthesizing monodisperse Si-DDR particles of ∼1.3-10 μm by varying the seed amount. These Si-DDR particles were deposited onto porous α-Al2O3 discs via sonication-induced assembly, constituting close-packed h0h-oriented layers.
Boudon Julien - - 2013
A SPIO-phthalocyanine nanohybrid is developed as a bimodal contrast agent for Optical and Magnetic Resonance Imaging. The organic coating was covalently attached onto SPIO in a step-by-step approach. Each coated-SPIO was thoroughly characterized. The hydrodynamic size of the SPIO-Pc is ca. 60 nm with a coverage of ca. 690 Pc/SPIO.
Eigler Siegfried - - 2013
The efficiency of reducing agents for the reduction of graphene oxide (GO) could be probed by scanning Raman spectroscopy. A film of graphene flakes derived from GO was probed to be graphene like. We also focus on the surface quality of reduced GO (rGO).
Springuel-Huet Marie-Anne - - 2013
Structural changes in a porous hybrid inorganic-organic ZIF-8 compound have been explored using hyperpolarized (129)Xe NMR of adsorbed xenon at various temperatures. Upon xenon adsorption at low temperature, the organic linkers undergo a reorientation leading to a stepwise increase in xenon adsorption and in chemical shift.
Racine Emilie - - 2013
The N-cyclopropylation of aromatic and aliphatic secondary acyclic amides, known to be poor nucleophiles, has been accomplished using a simple and cheap copper system. The corresponding tertiary acyclic amides, which constitute a wide family of biologically active compounds, have been obtained in good to excellent yields.
Yoo Jongtae - - 2013
Molecular adsorption onto carbon nanotube surfaces is one of the important topics in the science and technology of carbon nanotubes due to their specific 1D structures with very high aspect ratios. In order to reveal the effect of bundles of single-walled carbon nanotubes (SWNTs) on molecular adsorption at the molecular ...
Chang Tinghsun - - 2013
The properties of capacity-type microplasma devices were significantly enhanced due to the utilisation of hybrid diamond films as cathodes. The performance of the microplasma devices was closely correlated with the electron field emission (EFE) properties of the diamond cathode materials. The nanoemitters, which were prepared by growing duplex-structured diamond films ...
Kourkoutis Lena F - - 2013
All-Si tandem solar cells based on Si quantum dots (QDs) are a promising approach to future high-performance, thin film solar cells using abundant, stable and non-toxic materials. An important prerequisite to achieve a high conversion efficiency in such cells is the ability to control the geometry of the Si QD ...
Tang Peizhe - - 2013
To resolve the controversy over the functionalization effect on conductivity, we systematically investigate the structural and electronic properties of graphene covalently functionalized with phenyl groups. Using first-principles calculations combined with the model Hamiltonian analysis, we find that the structural stability, electronic and transport properties of the functionalized graphene are strongly ...
Zhang Qian - - 2013
Metal oxides are of paramount importance in heterogeneous catalysis as either supports or active phases. Controlled synthesis of one-dimensional (1D) metal oxide nanostructures has received enormous attention in heterogeneous catalysis due to the possibility of tailoring the properties of metal oxides by tuning their shapes, sizes, and compositions. This feature ...
Uttamapinant Chayasith - - 2013
This protocol describes an efficient method to site-specifically label cell-surface or purified proteins with chemical probes in two steps: probe incorporation mediated by enzymes (PRIME) followed by chelation-assisted copper-catalyzed azide-alkyne cycloaddition (CuAAC). In the PRIME step, Escherichia coli lipoic acid ligase (LplA) site-specifically attaches a picolyl azide (pAz) derivative to ...
Geim A K - - 2013
Research on graphene and other two-dimensional atomic crystals is intense and is likely to remain one of the leading topics in condensed matter physics and materials science for many years. Looking beyond this field, isolated atomic planes can also be reassembled into designer heterostructures made layer by layer in a ...
Moser D E - - 2013
Invaluable records of planetary dynamics and evolution can be recovered from the geochemical systematics of single meteorites. However, the interpreted ages of the ejected igneous crust of Mars differ by up to four billion years, a conundrum due in part to the difficulty of using geochemistry alone to distinguish between ...
Våge Selina - - 2013
Arising from Y. Zhao et al. Nature 494, 357–360 (2013). The recent findings of abundant SAR11 viruses by Zhao et al. are intriguing, and add new insight into the on-going discussion of why SAR11 bacteria are highly successful in the pelagic ocean. On the basis of high SAR11 virus abundance, ...
Giovannoni Stephen - - 2013
Replying to S. Våge, J. E. Storesund & T. F. Thingstad Nature 499, http://dx.doi.org/10.1038/nature12387 (2013). In the debate about top-down versus bottom-up control, most would argue that both are important. The most probable scenario is that in the absence of high rates of transport, the equilibrium between these competing processes ...
Sudrik Chaitanya - - 2013
We developed a strategy to create novel genetically encoded switches based on translational repression. We illustrated its efficacy by incorporating two copies of an RNA hairpin in the 5'-untranslated region (UTR) of a target mRNA and demonstrating 7-fold translational repression upon expression of a ligand - the BIV Tat peptide.
Gole Bappaditya - - 2013
An electron rich porous metal-organic framework (MOF) has been synthesized, which acts as an effective heterogeneous catalyst for Diels-Alder reactions through encapsulation of the reactants in confined nano-channels of the framework.
Lauber Markus B - - 2013
The asymmetric desymmetrization of 4,6-diprotected myo-inositol derivatives was achieved by using a bifunctional, readily available nucleophilic catalyst. The orthogonally protected products were obtained in 80-99% yield with 90-99% ee. Such structures serve as potential enantiopure building blocks for the synthesis of myo-inositol phosphates.
Wang Huaimin - - 2013
Here we reported a novel biohybrid hydrogel system with the potential for cell culture and controlled drug release.
Feng Quanyou - - 2013
An electron donor and acceptor, respectively, is embedded into naphtho[2,1-b:3,4-b']dithiophene based organic sensitizers to tune their optoelectronic properties. The DSSC based on FNE52 containing an auxiliary electron acceptor displays a maximum power conversion efficiency of 8.2% and good long-term stability.
Rudola Ashish - - 2013
The ultra-fast (30C or 2 min) rate capability and impressive long cycle life (>5000 cycles) of Na2Ti6O13 are reported. A stable 2.5 V sodium-ion battery full cell is demonstrated. In addition, the sodium storage mechanism and thermal stability of Na2Ti6O13 are discussed.
van Weerdenburg Bram J A - - 2013
SABRE hyperpolarizes substrates by polarization transfer from para-hydrogen in a metal complex. We have measured the signal enhancement of pyridine and its exchange rate in various [Ir(NHC)(Py)3(H)2](+) complexes to gain insight into their dependence on the N-Heterocyclic Carbene (NHC) ligand's steric and electronic properties.
Pan Jie - - 2013
Human soluble guanylate cyclase (hsGC), a NO sensor/NO receptor of a heterodimeric hemoprotein, plays a critical role in the NO-sGC-cGMP signaling pathway, and also reveals a novel nitrite reductase activity. This indicates that hsGC could activate itself by catalytic reduction of nitrite to NO instead of receiving NO from nitric ...
Ueno Hiroshi - - 2013
The ionic conductivity of [Li(+)@C60](PF6(-)) was measured in o-dichlorobenzene, and found to be higher than that of TBA(+)PF6(-). Electrochemical reduction of [Li(+)@C60](PF6(-)) without any supporting electrolyte gave the monovalent radical anion Li(+)@C60˙(-), as confirmed by the characteristic ESR signal and NIR absorption band.
Osakada Fumitaka F Systems Neurobiology Laboratories, The Salk Institute for Biological Studies, La Jolla, California, - - 2013
Rabies viruses, negative-strand RNA viruses, infect neurons through axon terminals and spread trans-synaptically in a retrograde direction between neurons. Rabies viruses whose glycoprotein (G) gene is deleted from the genome cannot spread across synapses. Complementation of G in trans, however, enables trans-synaptic spreading of G-deleted rabies viruses to directly connected, ...
McGrath Matthew J - - 2013
The Gibbs free energy of solvation and dissociation of hydrogen chloride in water is calculated through a combined molecular simulation/quantum chemical approach at four temperatures between T = 300 and 450 K. The Gibbs free energy is first decomposed into the sum of two components: the Gibbs free energy of ...
Jung Sung Chul - - 2013
Fast Li transport inside the Si electrode of Li-ion batteries is retarded at the electrode surface. We investigated the intercalation of a Li atom into the surface and subsurface layers of Ge and Sn using density functional calculations. In the Ge and Sn surfaces, the Li atom diffuses about four ...
Chung Dong Young - - 2013
Heat treatment of nanoparticles could induce the surface rearrangement for more stable facet exposure induced by thermodynamics. By changing the heat treatment environment, we confirmed the correlation between the oxygen reduction activity and the effect of surface oxide and the degree of surface rearrangement of Pt nanoparticles. Native surface oxide ...
Duan Sai - - 2013
Structure and adsorption energy of carbon monoxide molecules adsorbed on the Pt(111) surfaces with various CO coverages in water as well as work function of the whole systems at room temperature of 298 K were studied by means of a hybrid method that combines classical molecular dynamics and density functional ...
Keller Avigail - - 2013
The synthesis of mesostructured silica from a tetrahydrofuran (THF) based sol-gel was carried out in the channels of an anodic alumina membrane (AAM) using the evaporation induced self-assembly (EISA) method. The effect of channel surface chemistry on the orientation of the in-channel hexagonal mesostructure was studied by treating the channel ...
Sacchetto V - - 2013
In this work, the interactions of methyl tert-butyl ether (MTBE) on different dealuminated high silica zeolites were studied by means of both experimental and computational approaches. Zeolites with different textural and surface features were selected as adsorbents and the effect of their physico-chemical properties (i.e. pore size architecture and type ...
Conterosito Eleonora - - 2013
Layered double hydroxides (LDH) are versatile materials used for intercalating bioactive molecules, both in pharmaceutical and cosmetic fields, with the purpose of protecting them from degradation, enhancing their water solubility to increase bioavailability, and/or obtaining modified release properties. The properties of the intercalation compounds of Mg/Al_LDH and Zn/Al_LDH with different ...
Lønstad Bleken Bjørn-Tore - - 2013
Herein we report FTIR in situ adsorption of molecular hydrogen, carbon monoxide, water, methanol, pyridine and 2,4,6-trimethylpyridine (collidine) on nanosheet H-ZSM-5 which was recently studied in the methanol to hydrocarbons (MTH) reaction. The nature of the hydroxyl groups and surface species are described in detail. The IR spectrum of nanosheet ...
Tiozzo Cristina - - 2013
Niobium-containing silica materials obtained by deposition via liquid-phase grafting or dry impregnation of niobocene(iv) dichloride are active and selective catalysts in the epoxidation of alkenes in the presence of aqueous hydrogen peroxide. The generation of the catalytically-active Nb species was followed step-by-step, and investigated using a combined DR-UV-Vis, NIR, Raman, ...
Amdursky Nadav - - 2013
The electrical conductivity via peptide networks was measured using conductive probe atomic force microscopy, where the tryptophan-containing peptide network (composed of Phe-Trp dipeptides) exhibited a superior (5 fold) conductivity in comparison to an all phenylalanine network (composed of Phe-Phe dipeptides). These results are in line with previous spectroscopic measurements exploring ...
Bradley Robert W - - 2013
Biological photo-voltaic systems are a type of microbial fuel cell employing photosynthetic microbes at the anode, enabling the direct transduction of light energy to electrical power. Unlike the anaerobic bacteria found in conventional microbial fuel cells that use metals in the environment as terminal electron acceptors, oxygenic photosynthetic organisms are ...
Memarzadeh Lotfabad Elmira - - 2013
We demonstrate that silicon nanowire (SiNW) Li-ion battery anodes that are conformally coated with TiO2 using atomic layer deposition (ALD) show a remarkable performance improvement. The coulombic efficiency is increased to ∼99%, among the highest ever reported for SiNWs, as compared to 95% for the baseline uncoated samples. The capacity ...
Zahn Stefan - - 2013
We present high-level benchmark calculations of interaction energies of 236 ion pair structures of ionic liquids constituting a new IL-2013 set. 33 different approaches using various basis sets are validated against these benchmark data. Overall, traditional functionals like B3LYP, without an explicit dispersion correction, should be avoided when investigating ionic ...
Deiana Chiara - - 2013
Integrated studies of CO adsorption on TiO2 materials of different morphology and surface complexity identify, for the first time, frustrated translational CO modes by detecting their combination with the CO stretching mode (νCO). All the considered materials exhibit IR spectra with low-intensity bands in the 2235-2205 cm(-1) range, a region ...
Morandi Sara - - 2013
The effect of water, in the temperature range 25-350 °C, and ammonia at RT on two different surface species formed on Pt-K/Al2O3 and Pt-Ba/Al2O3 NSR catalysts during NOx storage-reduction cycles was investigated. The surface species involved are nitrates, formed during the NOx storage step, and isocyanates, which are found to ...
Vindigni F - - 2013
Two gold based catalysts supported on ceria prepared by different methods (urea gelation coprecipitation, UGC, and coprecipitation, CP) have been synthesized and tested in the WGS reaction, showing quite different catalytic behaviors. Interestingly, the two catalysts have the same gold loading (3 wt% Au was inserted by deposition-precipitation) and the ...
Martins de Souza E Silva Juliana - - 2013
Disaggregated magadiite was obtained through ion-exchange in acidic media from magadiite intercalated in the synthesis with cetyltrimethylamonium cations. The combination of Soxhlet extraction and ultrasound during the procedure resulted in different morphology and different properties when compared with the pristine material, as observed by SEM. Thermal and surface properties studies ...
Crocellà Valentina - - 2013
In situ FTIR spectroscopy was employed to investigate some aspects of the ambient temperature (actually, IR-beam temperature) adsorption of acetone on various pure and sulfate-doped zirconia specimens. Acetone uptake yields, on all examined systems and to a variable extent, different types of specific molecular adsorption, depending on the kind/population of ...
Chen Ailian - - 2013
A novel hybrid of MoO2-ordered mesoporous carbon (MoO2-OMC) was prepared through a two-step solvothermal chemical reaction route. The electrochemical performances of the mesoporous MoO2-OMC hybrids were examined using galvanostatical charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS) techniques. The MoO2-OMC hybrid exhibits significantly improved electrochemical performance of high reversible capacity, ...
Veals Jeffrey D - - 2013
The isomerizations of 3-aza-benzvalene to pyridine and 3,4-diaza-benzvalene to pyridazine have been studied using ab initio methods with a multiconfigurational wavefunction. Transition states for both the allowed disrotatory and forbidden conrotatory pathways were located. The forbidden pathways proceed through an intermediate consisting of pyridine or pyridazine with a trans double ...
Nawrocki Grzegorz - - 2013
We determine potentials of the mean force for interactions of amino acids with four common surfaces of ZnO in aqueous solutions. The method involves all-atom molecular dynamics simulations combined with the umbrella sampling technique. The profiled nature of the density of water with the strongly adsorbed first layer affects the ...
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