Search results for "Method"
showing 10 items of 13253 documents
Linear chain surfactants at a planar interface: a comparative Monte Carlo study of several lattice models
1993
Linear chain surfactants in a densely packed arrangement (such as alkane chains in lipid monolayers in the “uniform tilt” structures) are described by a crude coarse-grained model where the endgroups grafted on the interface form a regular lattice and the chains are described by the bond fluctuation model with chains containing N = 4 effective monomers only. Square-well interactions between the monomers are studied for both the attractive and repulsive case for three choices of the interaction range. None of these models exhibits a structure with uniform tilt. For attractive interactions the last bond has a strong tendency to fold back thus leading to a very high density close to the interf…
A Combination of Visible-Light Organophotoredox Catalysis and Asymmetric Organocatalysis for the Enantioselective Mannich Reaction of Dihydroquinoxal…
2019
[EN] An enantioselective photooxidative Mannich reaction of dihydroquinoxalinones with ketones by the merger of organophotoredox and asymmetric organocatalysis is described. This protocol features very mild reaction conditions using simple and cheap catalysts (Eosin Y and (S)-Proline) for the synthesis of chiral quinoxaline derivatives with good to high yields (up to 94%) and excellent enantioselectivities (up to 99% ee).
Application prospects of silica core side-glowing optical fibers
2005
The side-emitting optical fibers are specially designed to stimulate leakage of the core-transmitted radiation via their side surfaces, so creating the effect of glowing tiny wires. The basic design concepts for this kind of optical fibers are discussed, as well as some of the present and potential future applications.
Public Administration and the Study of Political Order: Towards a Framework for Analysis
2020
The contribution of this study is two-fold: First, it outlines a conceptual framework on political order; and secondly, it offers empirical illustrations on the case of Nordic cooperation. Taken together, the article makes a plea for public administration scholarship in the study of political order. Political order consists of a relatively stable arrangement of institutions that are fairly formalized and institutionalized. A common political order, moreover, entails that relevant institutions: (i) are fairly independent of pre-existing institutions; (ii) are relatively integrated and internally cohesive; and (iii) are reasonably able to influence governance processes within other institutio…
ChemInform Abstract: Electrochemical Allylic Oxidation of Olefins: Sustainable and Safe
2016
The power you're supplying: With the application of an optimized electrochemical approach, the allylic oxidation of olefins, which is an important C-H activation process that provides access to enones, becomes a sustainable, versatile, and potent key reaction for organic synthesis.
Studi greci e latini nell?antica Università di Altamura (1748-1821)
2019
The article tries to highlight, despite the scarse of available documentation, the Greek and Latin studies (language and texts) in the ancient Apulian University in Altamura (1748-1821). Furthermore, on the basis of unpublished archival materials (school registers and student workbooks) it is possible to shed light on the ancient authors explained at school, the teaching methods, and the study practices.
A marching-on in time meshless kernel based solver for full-wave electromagnetic simulation
2012
A meshless particle method based on an unconditionally stable time domain numerical scheme, oriented to electromagnetic transient simulations, is presented. The proposed scheme improves the smoothed particle electromagnetics method, already developed by the authors. The time stepping is approached by using the alternating directions implicit finite difference scheme, in a leapfrog way. The proposed formulation is used in order to efficiently overcome the stability relation constraint of explicit schemes. In fact, due to this constraint, large time steps cannot be used with small space steps and vice-versa. The same stability relation holds when the meshless formulation is applied together w…
The feasibility of pulsed light processing in the meat industry
2019
Abstract Today, the increasing demand for minimally processed foods that are nutritious, sensorially acceptable, and free from microbial, chemical and physical hazards, challenges research and development to establish alternative methods to reduce the level of bacterial contamination. As one of the newly developing non-thermal methods, pulsed light is a technology for the fast, mild, and residue-free surface decontamination of meat and meat contact materials in the meat processing environment. This review provides specific information on pulsed light technology and the feasibility of its application for unpackaged and packaged meat and meat products as well as meat contact materials. The ad…
Non-chromatographic speciation
2010
We evaluate the main strategies for screening trace-element species in most types of sample to establish their strengths and weaknesses, as they offer fast, sensitive and cheaper alternatives to classical methods involving chromatography. We consider the principles of non-chromatographic speciation analysis, based on the different behaviors of chemical species before measurement by atomic and molecular spectrometry and electroanalytical methods, so as to give an update on the literature in this field of research.
Enantiodifferentiation of acyclic phosphonium salts in chiral liquid crystalline solutions
2006
Abstract The enantiodifferentiation of acyclic phosphonium salts bearing a stereogenic centre, whether on the phosphorus atom or on one of its substituents, was investigated by 2 H–{ 1 H}, 13 C–{ 1 H} and 31 P–{ 1 H} NMR in chiral liquid crystals composed of a polypeptide dissolved in an organic solvent. For the first time, the enantiomers of P-chirogenic phosphorus compounds were discriminated in these anisotropic media, affording good to excellent separation of the signals, allowing the determination of their proportion. While 31 P–{ 1 H} NMR spectra showed no chiral separation, 2 H–{ 1 H} NMR was efficient in the enantiodifferentiation of an isotopically labelled compound. Better still, …