Application Of Chemical Technologies Research Articles

Patent activity in the field of graphene microwave path elements GHZ range from the point of view of import independence

The patent activity in the field of graphene microwave path elements the GHz range is analyzed from 2004 (the year of graphene discovery) to the present from the point of view of import independence. The articles from SCOPUS and WoS were taken into account in analysis in addition to patents. The search was conducted by countries: Russia, USA, China, India, Great Britain, Germany, France, Italy, Spain, Japan, Iran, Malaysia; by branch of knowledge: technical applications, energy, applications in chemical technology, biotechnology, chemistry, applications in computer technology, applications of mathematics, also materials science and the field of physics and astronomy. The patent research methodology is based on conducting searches through a combination keywords, and IPC indexes. Statistical analysis of patent documents selected because of the search illustrates the main conclusions regarding inventive activity in the research area by IPC indices years of priority, countries.

Carbon Anode in Carbon History.

This study examines how the several major industries, associated with a carbon artifact production, essentially belong to one, closely knit family. The common parents are the geological fossils called petroleum and coal. The study also reviews the major developments in carbon nanotechnology and electrocatalysis over the last 30 years or so. In this context, the development of various carbon materials with size, dopants, shape, and structure designed to achieve high catalytic electroactivity is reported, and among them recent carbon electrodes with many important features are presented together with their relevant applications in chemical technology, neurochemical monitoring, electrode kinetics, direct carbon fuel cells, lithium ion batteries, electrochemical capacitors, and supercapattery.

Effect of drag correlation and bubble‐induced turbulence closure on the gas hold‐up in a bubble column reactor

AbstractBACKGROUNDGas–liquid hydrodynamics play an important role in processes across a wide range of applications in chemical technology and biotechnology. In most of these applications, gas is bubbled in the bottom of the reactor to conduct physical mixing or mixing‐induced chemical reaction. In either case, the gas bubble hydrodynamics play a critical role on the overall performance of these processes. In the present study, the gas–liquid multiphase system is simulated using a Eulerian–Eulerian two‐fluid Computational Fluid Dynamics (CFD) model.RESULTSThe physical model is a cylindrical bubble column contactor wherein gas is sparged into liquid through a perforated sparger with a superficial gas velocity of ≈3–40 cm s−1. The CFD model for the contactor is built using the free and open source tool OpenFOAM v.4.0 to simulate the gas–liquid system. The time‐averaged volume fraction distribution was studied at different heights in the column. The effect of drag force and bubble‐induced turbulence are studied to arrive at appropriate closures for the CFD model. The results obtained from the numerical simulations were validated against available experimental results found in literature.CONCLUSIONThe recommended models, based on the present CFD study of the bubble column reactor, are the Ishii–Zuber drag closure with the modification that the parameter p is set to 2 for superficial gas velocities ≤20 cm s−1 and is set to 4 for 40 cm s−1 superficial gas velocity) and the mixed k–ϵ model to account for drag correlation and bubble‐induced turbulence closure, respectively. © 2019 Society of Chemical Industry

Chaotic advection of fluid particles in a field of point vortices and vortex rings

Processes of formation of vortex rings and mushroom structures in the ocean, in geological structures in Earth’s mantle, and in various applications in chemical technology,1 provide conditions for advanced interest in the phenomena of internal mixing. In order to model such processes, an approach based on a direct study of the trajectories of motion of Lagrangian particles in a Eulerian velocity field currently attracts special attention. Although the ideas of such an approach may be found in the works of Maxwell2 and Reynolds,3 comparatively little has been done toward obtaining a clear view of what goes on, except in the simplest cases. To the more complicated cases belong the processes of chaotic advection of particles in bounded domains.4 This paper presents the results of a study of properties of chaotic particle advection of an ideal fluid in unbounded and bounded domains under free motion of point vortices or vortex rings. Data on the process of particle motion for particles that initially form the ‘‘atmosphere’’ of a vortex pair when it interacts with a single vortex, or with other noncollinear vortex pairs, are presented for a two-dimensional unbounded domain. Depending on the type of interaction—either ‘‘direct’’ or ‘‘exchange’’ collision or mutual trapping5–7—an estimate of the effectiveness of stirring of atmosphere particles and chaotization of their trajectories is given. The problem of advection of particles in a two-dimensional rectangular domain with a free vortex is solved. Although the locked trajectory of the vortex and the period of its revolution are explicitly calculated by means of Jacobi and Weierstrass elliptic functions, a complicated dependence of the streamfunction on time leads to the formation of ‘‘whorls’’ and ‘‘tendrils,’’ and to effective stirring of some domains. Poincaré sections of particles for characteristic values of the geometrical parameters of the domain and initial positions of the vortex are given. Various types of interaction such as ‘‘leap-frogging,’’ passing and mutual trapping,8 are studied for the axisymmetric motion of two coaxial vortex rings with the intensities of vorticity of the same or different signs. An analysis of chaotization of the motion for particles initially forming the atmosphere of the rings has been carried out for some cases of interaction.

Some interesting measurements with quadrupole mass spectrometers

Some measurements made with the NZ-850 type quadrupole mass spectrometer of the ATOMKI are reported. The analysis of gases in operating rooms showed 1 ppm— 105 ppm concentration of narcotics. Purity control of gases regularly helps the radioactive pollution measurements and radio carbon dating technique at our Institute. In an other application evidence of new possibilities is given which arise from coupling the quadrupole to electron diffraction apparatus. Examples of blood gas analyses and some applications in chemical technology are also given.