In molecular dynamics (MD) simulations the need often arises to maintain such parameters as temperature or pressure rather than energy and volume, or to impose gradients for studying transport properties in nonequilibrium MD A method is described to realize coupling to an external bath with constant temperature or pressure with adjustable time constants for the coupling The method is easily extendable to other variables and to gradients, and can be applied also to polyatomic molecules involving internal constraints The influence of coupling time constants on dynamical variables is evaluated A leap‐frog algorithm is presented for the general case involving constraints with coupling to both a constant temperature and a constant pressure bath

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Molecular dynamics with coupling to an external bath.

A molecular dynamics simulation method which can generate configurations belonging to the canonical (T, V, N) ensemble or the constant temperature constant pressure (T, P, N) ensemble, is proposed. The physical system of interest consists of N particles (f degrees of freedom), to which an external, macroscopic variable and its conjugate momentum are added. This device allows the total energy of the physical system to fluctuate. The equilibrium distribution of the energy coincides with the canonical distribution both in momentum and in coordinate space. The method is tested for an atomic fluid (Ar) and works well.

A molecular dynamics method for simulations in the canonical ensemble

A stoichiometric derivative of graphene with a fluorine atom attached to each carbon is reported Raman, optical, structural, micromechanical, and transport studies show that the material is qualitatively different from the known graphene-based nonstoichiometric derivatives Fluorographene is a high-quality insulator (resistivity >10(12) Omega) with an optical gap of 3 eV It inherits the mechanical strength of graphene, exhibiting a Young's modulus of 100 N m(-1) and sustaining strains of 15% Fluorographene is inert and stable up to 400 degrees C even in air, similar to Teflon

/pdf/fluorographene-a-two-dimensional-counterpart-of-teflon-2eoe4l6d9z.pdf

Fluorographene: A Two‐Dimensional Counterpart of Teflon

As compared to bulk materials, magnetic nanoparticles possess distinct magnetic properties and attempts have been made to exploit their beneficial properties for technical and biomedical applications, e.g. for magnetic fluids, high-density magnetic recording, or biomedical diagnosis and therapy. Early magnetic fluids (MFs) were produced by grinding magnetite with heptane or long chain hydrocarbon and a grinding agent, e.g. oleic acid [152]. Later procedures for MFs precipitated Fe 3+/Fe 2+ of an aqueous solution with a base, coated the particles by oleic acid, and dispersed them in carrier liquid [161]. However, besides the elemental composition and crystal structure of the applied magnetic particles, particle size and particle size distribution determine the properties of the resulting MF. Many methods for nanoparticle synthesis including the preparation of metallic magnetic particles have been described in the literature. However, there still remain important questions, e.g. concerning control of particle size, shape, and monodispersity as well as their stability towards oxidation. Moreover, peptization by suitable surfactants or polymers into stable MFs is an important issue since each application in engineering or biomedicine needs special MFs with properties adjusted to the requirements of the system.

Synthesis and Characterization

https://cyberleninka.org/article/n/323323.pdf

Production and processing of graphene and 2d crystals

Elektrochemische fluorierung von n-propyl-, diaethyl- und triaethylamin

ESCA spectra showed that the anodic films formed on nickel in liquid hydrogen fluoride consisted of oxyfluorides of nickel even at a very low water concentration. The in-depth composition of the films changed characteristically depending on the amount of water contained in liquid hydrogen fluoride. The atomic ratio of fluorine to oxygen was the highest at the surface region of the anode in solutions containing H 2 O of less than 5 x 10 −3 M, whereas the addition of 0.5 M H 2 O made it the lowest at the surface region throughout the film and reduced the film thickness. The F ls spectrum of a nickel anode polarized at 6.5 V in a solution containing H 2 O of less than 5 x 10 −3 M indicated that fluorine was dissociatively absorbed in the film and that this might act as a fluorinating agent for perfluorination of organic compounds in liquid hydrogen fluoride.

An esca study of the anodic film on nickel in liquid hydrogen fluoride

The mutual solubilities of Li–LiCl and Li–LiCl–KCl systems were determined both in liquid-liquid and solid-liquid equilibrium regions. No critical solution temperature was observed for Li–LiCl system. The enthalpy of solution of LiCl in Li was estimated and compared with those for other alkali metal-alkali halides.

Miscibility of lithium with lithium chloride and lithium chloride-potassium chloride eutectic mixture

Excess Enthalpies of Propanediol+Water Systems at 298.15K

L'INVENTION CONCERNE UN NOUVEAU COMPOSE D'INTERCALATION TERNAIRE D'UN GRAPHITE AVEC UN FLUORURE METALLIQUE ET DU FLUOR CE COMPOSE D'INTERCALATION EST REPRESENTE PAR LA FORMULE CF(MF) DANS LAQUELLE M EST UN METAL PRODUIT PAR LA REACTION D'UN MATERIAU DE GRAPHITE AVEC UN FLUORURE METALLIQUE DANS UNE ATMOSPHERE DE FLUOR GAZ A UNE TEMPERATURE DE 0C A 400C POUR AU MOINS UNE PERIODE DE TEMPS SUFFISANTE POUR EFFECTUER UNE AUGMENTATION EN POIDS DANS LE GRAPHITE LE COMPOSE D'INTERCALATION DE GRAPHITE TERNAIRE AINSI OBTENU PRESENTE NON SEULEMENT UNE EXCELLENTE STABILITE A L'HUMIDITE MAIS EGALEMENT UNE CONDUCTIVITE ELECTRIQUE ELEVEE DE SORTE QU'IL EST EN PRATIQUE UTILISE COMME NOUVEAU MATERIAU ELECTRIQUEMENT CONDUCTEUR ET COMME CATALYSEUR DE REACTION ORGANIQUE

Compose d'intercalation ternaire d'un graphite avec un fluorure metallique et du fluor, procede pour sa preparation, et materiau electriquement conducteur comprenant le compose d'intercalation ternaire

Nobuatsu Watanabe

Papers

Elektrochemische fluorierung von n-propyl-, diaethyl- und triaethylamin

An esca study of the anodic film on nickel in liquid hydrogen fluoride

Miscibility of lithium with lithium chloride and lithium chloride-potassium chloride eutectic mixture

Excess Enthalpies of Propanediol+Water Systems at 298.15K

Compose d'intercalation ternaire d'un graphite avec un fluorure metallique et du fluor, procede pour sa preparation, et materiau electriquement conducteur comprenant le compose d'intercalation ternaire