Scientometric Picture of the Evolution of the Literature of Automation in Spectroscopy and Its Current State

The current study focuses on the status of automation and mechanization in spectroscopy for analytical chemistry publications compiled during the period 1980–2006, in Analytical Abstracts. Flow injection analysis (FIA), sequential injection analysis (SIA), multicommutation, and monosegmented and segmented flow strategies were considered. For assessing the evolution of scientific productivity, the total number of publications concerned with the different methodologies was evaluated. In order to provide a picture of the state of the art of this field, the most important journals, the most active authors, and the most productive countries in the field of automation were evaluated in the period of the first years of this century.     

Nanomaterial‐based Sensors for the Study of DNA Interaction with Drugs

The interaction of drugs with DNA has been searched thoroughly giving rise to an endless number of findings of undoubted importance, such as a prompt alert to harmful substances, ability to explain most of the biological mechanisms, or provision of important clues in targeted development of novel chemotherapeutics. The existence of some drugs that induce oxidative damage is an increasing point of concern as they can cause cellular death, aging, and are closely related to the development of many diseases. Because of a direct correlation between the response, strength/ nature of the interaction and the pharmaceutical action of DNA‐targeted drugs, the electrochemical analysis is based on the signals of DNA before and after the interaction with the DNA‐targeted drug. Nowadays, nanoscale materials are used extensively for offering fascinating characteristics that can be used in designing new strategies for drug‐DNA interaction detection. This work presents a review of nanomaterials (NMs) for the study of drug‐nucleic acid interaction. We summarize types of drug‐DNA interactions, electroanalytical techniques for evidencing these interactions and quantification of drug and/or DNA monitoring.     

Classical two-slit interference effects in double photoionization of molecular hydrogen at high energies

Recent experiments on double photoionization of H2 with photon energies between 160 and 240 eV have revealed body-frame angular distributions that suggest classical two-slit interference effects may be present when one electron carries most of the available energy and the second electron is not observed. We report precise quantum mechanical calculations that reproduce the experimental findings. They reveal that the interpretation in terms of classical diffraction is only appropriate at substantially higher photon energies. At the energies considered in the experiment we offer an alternative explanation based on the mixing of two nondiffractive contributions by circularly polarized light.     

Photoluminescence characterization of silicon nanostructures embedded in silicon oxide

This paper describes a simple method to analyze the photoluminescent characteristics of materials based on embedded light-emitting nanoclusters. Photoluminescence spectra of deposited silicon sub-oxide layers with the same composition and different thicknesses have been obtained. A saturation of the total luminescence intensity is observed with increase in thickness. By analyzing the photoluminescence spectra several optical and structural parameters can be evaluated. We thus propose a model in which the absorption of light from a nanostructure layer implies the possibility of subsequent luminescence and affects the underlying layers as well. By fitting the data to the developed model, two fundamental parameters are extracted: nanostructures absorption probability, which is independent of the emission energy and the spectra of emission probability of an excited nanostructure which fits a Gaussian shape.     

Size dependent photoluminescence of SiC nanocrystals

The paper presents the results of porous SiC study using photoluminescence and scanning electronic microscopy. It is shown that the intensity of defect-related PL bands (2.08, 2.27, 2.44 and 2.63 eV) increases monotonically with the rise of PSiC thickness from 2.1 up to 12.0 μm. These luminescence centers are assigned to surface defects which appear at the PSiC etching process. Photoluminescence intensity stimulation for surface defects is attributed to rise of defect concentrations with increasing of porous layer thickness and to realization of the hot carrier ballistic mechanism at surface defect excitation. Intensity enhancement for exciton-related PL bands (2.79, 2.98 and 3.26 eV ) is attributed to increasing the exciton recombination rate as result of exciton weak confinement in big size SiC NCs of different polytypes (6H–PSiC with inclusions of 15R- and 4H–PSiC).     

Distributionally robust stochastic programs with side information based on trimmings

Mathematical Programming - We consider stochastic programs conditional on some covariate information, where the only knowledge of the possible relationship between the uncertain parameters and the...     

Electrocatalytic Oxidation of 5‐(Hydroxymethyl)furfural Using High‐Surface‐Area Nickel Boride

The electrochemical oxidation of the biorefinery product 5‐(hydroxymethyl)furfural (HMF) to 2,5‐furandicarboxylic acid (FDCA), an important platform chemical for the polymer industry, is receiving increasing interest. FDCA‐based polymers such as polyethylene 2,5‐furandicarboxylate (PEF) are sustainable candidates for replacing polyethylene terephthalate (PET). Herein, we report the highly efficient electrocatalytic oxidation of HMF to FDCA, using Ni foam modified with high‐surface‐area nickel boride (Ni_xB) as the electrode. Constant potential electrolysis in combination with HPLC revealed a high faradaic efficiency of close to 100 % towards the production of FDCA with a yield of 98.5 %. Operando electrochemistry coupled to ATR‐IR spectroscopy indicated that HMF is oxidized preferentially via 5‐hydroxymethyl‐2‐furancarboxylic acid rather than via 2,5‐diformylfuran, which is in agreement with HPLC results. This study not only reports a low‐cost active electrocatalyst material for the electrochemical oxidation of HMF to FDCA, but additionally provides insight into the reaction pathway.     

Electrocatalysis of As(III) oxidation by cobalt oxide nanoparticles: measurement and modeling the effect of nanoparticle amount on As(III) oxidation potential

Journal of Solid State Electrochemistry - The performance of electrodes modified with electrochemically generated cobalt oxide nanoparticles for the oxidation of As(III) species was investigated by...