Gels in Medicine and Surgery: Current Trends and Future Perspectives

In this paper, the plasma discharge in a high-pressure fluid stream in order to produce gaseous hydrogen was studied. Methods and equipment have been developed for the excitation of a plasma discharge in a stream of liquid medium. The fluid flow under excessive pressure is directed to a hydrodynamic emitter located at the reactor inlet where a supersonic two-phase vapor-liquid flow under reduced pressure is formed in the liquid due to the pressure drop and decrease in the flow enthalpy. Electrodes are located in the reactor where an electric field is created using an external power source (the strength of the field exceeds the breakdown threshold of this two-phase medium) leading to theinitiation of a low-temperature glow quasi-stationary plasma discharge.A theoretical estimation of the parameters of this type of discharge has been carried out. It is shown that the lowtemperature plasma initiated under the flow conditions of a liquid-phase medium in the discharge gap between the electrodes can effectively decompose the hydrogen-containing molecules of organic compounds in a liquid with the formation of gaseous products where the content of hydrogen is more than 90%. In the process simulation, theoretical calculations of the voltage and discharge current were also made which are in good agreement with the experimental data. The reaction unit used in the experiments was of a volume of 50 ml and reaction capacity appeared to be about 1.5 liters of hydrogen per minute when using a mixture of oxygen-containing organic compounds as a raw material. During their decomposition in plasma, solid-phase products are also formed in insignificant amounts: carbon nanoparticles and oxide nanoparticles of discharge electrode materials.

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Current Trends and Future Perspectives Regarding Elective Rotations

Case Medical Research ◽

10.31525/ct1-nct04180917 ◽

2019 ◽

Author(s):

Keyword(s):

Future Perspectives ◽

Current Trends

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The influence of the Stokes and Archimedes forces on the stability of a two-phase flow

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2003.1.020 ◽

2003 ◽

Vol 3 ◽

pp. 266-270

Author(s):

B.H. Khudjuyerov ◽

I.A. Chuliev

Keyword(s):

Spectral Method ◽

Stability Region ◽

Gas Flow ◽

Two Phase Flow ◽

Solid Phase ◽

Stability Characteristic ◽

Phase Flow ◽

Two Phase ◽

The Stability

The problem of the stability of a two-phase flow is considered. The solution of the stability equations is performed by the spectral method using polynomials of Chebyshev. A decrease in the stability region gas flow with the addition of particles of the solid phase. The analysis influence on the stability characteristic of Stokes and Archimedes forces.

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CFD Simulation of Solid Suspension for a Liquid–Solid Industrial Stirred Reactor

Applied Sciences ◽

10.3390/app11125705 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5705

Author(s):

Adrian Stuparu ◽

Romeo Susan-Resiga ◽

Alin Bosioc

Keyword(s):

Chemical Reaction ◽

Cfd Simulation ◽

Simulation Analysis ◽

Solid Phase ◽

Initial Conditions ◽

Chemical Reactor ◽

Liquid Mixtures ◽

Multiphase Model ◽

Chemical Product ◽

Two Phase

The present study examines the possibility of using an industrial stirred chemical reactor, originally employed for liquid–liquid mixtures, for operating with two-phase liquid–solid suspensions. It is critical when obtaining a high-quality chemical product that the solid phase remains suspended in the liquid phase long enough that the chemical reaction takes place. The impeller was designed for the preparation of a chemical product with a prescribed composition. The present study aims at finding, using a numerical simulation analysis, if the performance of the original impeller is suitable for obtaining a new chemical product with a different composition. The Eulerian multiphase model was employed along with the renormalization (RNG) k-ε turbulence model to simulate liquid–solid flow with a free surface in a stirred tank. A sliding-mesh approach was used to model the impeller rotation with the commercial CFD code, FLUENT. The results obtained underline that 25% to 40% of the solid phase is sedimented on the lower part of the reactor, depending on the initial conditions. It results that the impeller does not perform as needed; hence, the suspension time of the solid phase is not long enough for the chemical reaction to be properly completed.

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Kinematic and Dynamic Parameters of a Liquid-Solid Pipe Flow Using DPIV∕Accelerometry

Journal of Fluids Engineering ◽

10.1115/1.2786537 ◽

2007 ◽

Vol 129 (11) ◽

pp. 1415-1421 ◽

Cited By ~ 5

Author(s):

Joseph Borowsky ◽

Timothy Wei

Keyword(s):

Pipe Flow ◽

Solid Phase ◽

Fluid Phase ◽

Central Moment ◽

Steady Flows ◽

Dynamic Parameters ◽

Two Phase ◽

Turbulence Structures ◽

Two Phases ◽

Flat Profile

An experimental investigation of a two-phase pipe flow was undertaken to study kinematic and dynamic parameters of the fluid and solid phases. To accomplish this, a two-color digital particle image velocimetry and accelerometry (DPIV∕DPIA) methodology was used to measure velocity and acceleration fields of the fluid phase and solid phase simultaneously. The simultaneous, two-color DPIV∕DPIA measurements provided information on the changing characteristics of two-phase flow kinematic and dynamic quantities. Analysis of kinematic terms indicated that turbulence was suppressed due to the presence of the solid phase. Dynamic considerations focused on the second and third central moments of temporal acceleration for both phases. For the condition studied, the distribution across the tube of the second central moment of acceleration indicated a higher value for the solid phase than the fluid phase; both phases had increased values near the wall. The third central moment statistic of acceleration showed a variation between the two phases with the fluid phase having an oscillatory-type profile across the tube and the solid phase having a fairly flat profile. The differences in second and third central moment profiles between the two phases are attributed to the inertia of each particle type and its response to turbulence structures. Analysis of acceleration statistics provides another approach to characterize flow fields and gives some insight into the flow structures, even for steady flows.

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Current trends and future perspectives of nanomedicine for the management of colon cancer

European Journal of Pharmacology ◽

10.1016/j.ejphar.2021.174464 ◽

2021 ◽

pp. 174464

Author(s):

Shadma Wahab ◽

Mohammad Y. Alshahrani ◽

M.D. Faruque Ahmad ◽

Hashim Abbas

Keyword(s):

Colon Cancer ◽

Future Perspectives ◽

Current Trends

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On the Natural Lubrication of Synovial Joints: Normal and Degenerate

Journal of Lubrication Technology ◽

10.1115/1.3453003 ◽

1977 ◽

Vol 99 (2) ◽

pp. 163-172 ◽

Cited By ~ 28

Author(s):

Joseph M. Mansour ◽

Van C. Mow

Keyword(s):

Articular Cartilage ◽

Solid Phase ◽

Articular Surface ◽

Moving Load ◽

Frictional Resistance ◽

Elastic Solid ◽

Surface Load ◽

Two Phase ◽

Tissue Properties ◽

Synovial Joints

Fluid flow and mass transport mechanisms associated with articular cartilage function are important biomechanical processes of normal and pathological synovial joints. A three-layer permeable, two-phase medium of an incompressible fluid and a linear elastic solid are used to model the flow and deformational behavior of articular cartilage. The frictional resistance of the relative motion of the fluid phase with respect to the solid phase is given by a linear diffusive dissipation term. The subchondral bony substrate is represented by an elastic solid. The three-layer model of articular cartilage is chosen because of the known histological, ultrastructural, and biomechanical variations of the tissue properties. The calculated flow field shows that for material properties of normal healthy articular cartilage the tissue creates a naturally lubricated surface. The movement of the interstitial fluid at the surface is circulatory in manner, being exuded in front and near the leading half of the moving surface load and imbibed behind and near the trailing half of the moving load. The flow fields of healthy tissues are capable of sustaining a film of fluid at the articular surface whereas pathological tissues cannot.

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