Search results for " split"
showing 10 items of 264 documents
Synthesis and spectroscopic characterization of diethyltin (IV) derivatives of dipeptides: Crystal and molecular structure of diethyltin glycyltrosin…
1992
Dipeptide complexes of the diethyltin(IV) moiety, Et2SnL, have been synthesized, H2L being glycylglycine (H2GlyGly), glycylalanine (H2GlyAla), alanylalanine (H2AlaAla), glycylvaline (H2GlyVal), valylvaline (H2ValVal), glycylmethionine (H2GlyMet), glycyltyrosine (H2GlyTyr). The crystal and molecular structure of the complex Et2SnGlyTyr has been determined by singlecrystal X-ray diffraction. It consists of monomeric units, with the tin atom having a considerably distorted trigonal bipyramidal environment. The dipeptide acts as a tridentate ligand bonding the tin of the C2Sn fragment (equatorial carbon atoms) with the peptide nitrogen atom (equatorial) and axial (monodentate) carboxyl oxygen a…
Looking for representative fit models for apparel sizing
2014
This paper is concerned with the generation of optimal fit models for use in apparel design. Representative fit models or prototypes are important for defining a meaningful sizing system. However, there is no agreement among apparel manufacturers and each one has their own prototypes and size charts i.e. there is a lack of standard sizes in garments from different apparel manufacturers. We propose two algorithms based on a new hierarchical partitioning around medoids clustering method originally developed for gene expression data. We are concerned with a different application; therefore, the dissimilarity between the objects has to be different and must be designed to deal with anthropometr…
Tensor-product states and local indistinguishability: an optical linear implementation
2000
In this paper we investigate the properties of distinguishability of an orthogonal set of product states of two three level particle system by a simple class of joint measures. Here we confine ourselves to a system of analysis built up of linear elements, such as beam splitters and phase shifters, delay lines, electronically switched linear devices and auxiliary photons. We present here the impossibility of realization of a perfect never falling analyzer with this tools.
Synthesis and characterization of four novel manganese(II) chains formed by 4,4′-azobis(pyridine) and benzoate or nitrobenzoates: Stabilization of un…
2013
Abstract Four new manganese(II) coordination polymers: [Mn(4,4′-azpy)(C6H5COO)2](4,4′-azpy)0.5 (1), [Mn(4,4′-azpy)(p-(NO2)C6H4COO)2] (2), [Mn(4,4′-azpy)(m-(NO2)C6H4COO)2] (3) and [Mn(4,4′-azpy)(o-(NO2)C6H4COO)2(H2O)2] (4), where 4,4′-azpy = 4,4′-azobis(pyridine), have been synthesized by self-assembly of MnX2 (X = benzoate, p-, m-, or o-nitrobenzoates) together with 4,4′-azpy. All four complexes were characterized by elemental analyses, IR spectroscopy, thermal analyses, single-crystal X-ray diffraction analyses and variable-temperature magnetic measurements. The structural analyses reveal that complexes 1, 2 and 3 feature a 1D molecular ladder formed by syn–syn (complex 1) or syn–anti (com…
Ni and Ni-Pd nanostructures electrodes for water-alkaline electrolyses
2017
Hydrogen production by water electrolysis (WE) is a very promising technology because it is a pollution free-process specially if renewable energy are employed. Up to day, the cost of hydrogen production by WE is higher than other available technologies, making WE not competitive. Many efforts have been made to improve WE performance, through the use of electrodes made of transition metal alloys (Pt2Mo, TiPt) as a cathode or pyrochlore type oxide (Tl2RuxIr2-xO7) as an anode [1]. In the field of water-alkaline electrolyzer, the development of cheap nanoporous nickel electrodes with high electrocatalytic features is one of the potential approaches to increase the WE performance [2]., A facile…
Au/TiO2-CeO2 Catalysts for Photocatalytic Water Splitting and VOCs Oxidation Reactions
2016
Photocatalytic water splitting for H2 production and photocatalytic oxidation of 2-propanol, an example of volatile organic compounds, were investigated over TiO2 catalysts loaded with gold and/or ceria. In the water splitting reaction the presence of gold only slightly affected the performance of TiO2 whereas the presence of CeO2 had a more remarkable positive effect. In the 2-propanol oxidation Au/TiO2 was the most active sample in terms of alcohol conversion whereas Au/TiO2-CeO2 exhibited the highest CO2 yield. On the basis of characterization experiments (X-Ray Diffraction (XRD), Energy Dispersive X-ray Analysis EDX, surface area measurements, Diffuse Reflectance Spectroscopy (DRS) and …
Low temperature conversion of levulinic acid into γ-valerolactone using Zn to generate hydrogen from water and nickel catalysts supported on sepiolite
2020
1 scheme, 2 tables, 7 figures.-- Supplementary material available.
Water splitting through model surfaces of metal oxides : ferroelectric polarization towards water adsorption processes
2019
The properties of out-of-plane polarized BaTiO3(001) thin films were investigated from first-principles calculations and photoemission spectroscopy. Firstly, density functional theory calculations (DFT) were used to unravel the nature of the Pt(001)/BaTiO3(001) interface. In particular, the influence of the substrate on the ferroelectric properties of the BaTiO3 overlayer has been studied. Among the results, it can be pointed that platinum tends to increase the ferroelectric domain size of BaTiO3.Then, the adsorption of water on BaTiO3 was described by means of DFT calculations. The impact of the polarization as well as the influence of the nature of the surface termination on water adsorpt…
Long time behavior for a dissipative shallow water model
2013
We consider the two-dimensional shallow water model derived by Levermore and Sammartino (Nonlinearity 14,2001), describing the motion of an incompressible fluid, confined in a shallow basin, with varying bottom topography. We construct the approximate inertial manifolds for the associated dynamical system and estimate its order. Finally, considering the whole domain R^2 and under suitable conditions on the time dependent forcing term, we prove the L^2 asymptotic decay of the weak solutions.
Mössbauer spectroscopy of mono-organotin(IV) derivatives
1974
Abstract The Mossbauer parameters isomer shift, δ, and quadrupole splitting, ΔE, of mono-organotin compounds insofar investigated have been collected and tabulated. It is demonstrated that isomer shifts consistently depend on ligand electronegativities and coordination numbers, from which it is deduced that RSn IV behave much more as Sn IV rather than R 2 Sn IV and R 3 Sn IV derivatives. The changes of δ for RSn IV are then interpreted by hypotheses analogous to those advanced for Sn IV and its adducts and complexes. It is also inferred that in RSn IV compounds there is a consistent s-character in all tin-ligand atom bonds.