scholarly journals Testing Sorption Properties of Halloysite by Means of the Laser Interferometry Method

2015 ◽  
Vol 37 (1) ◽  
pp. 43-47
Author(s):  
Sławomir Wąsik ◽  
Michał Arabski ◽  
Karolina Maciejec ◽  
Grażyna Suchanek ◽  
Anna Świercz
Keyword(s):  
Concentration Field ◽  
Laser Interferometry ◽  
Membrane System ◽  
Absorption Capacity ◽  
Sorption Properties ◽  
Concentration Profiles ◽  
Adsorbed Substance ◽  
Interferometry Method ◽  
Set Up ◽  
Kinetics Of

The objective of the present study has been to test the laser interferometry method in terms of its usability for investigating sorption properties of minerals. This method was used to test the absorption capacity of halloysite with reference to glucose, which is often found in industrial wastewater and whose excess can disturb the environmental eco-balance. The sorption capacity of halloysite was thus determined indirectly, basing on the comparison of concentration profiles as well as time characteristics of glucose quantities released from the control solution and from the solution incubated with a halloysite adsorbent. An analysis of glucose diffusion was conducted in a two-chamber membrane system. On the basis of the obtained concentration profiles, the evolution of the concentration field was determined; so were the removal efficiency (%) and the amount of glucose adsorbed at equilibrium (qe, mg/g). The obtained results confirm good sorption properties of halloysite with respect to the investigated substance as well as usability of the method for this kind of investigations. The presented tests suggest that the measurement set-up can be optimised in such as way that visual rendering and testing the kinetics of the adsorbed substance direct release from the studied material become possible.

scholarly journals Application of the Laser Interferometry in Studies of Biophysical Model Systems

2013 ◽  
Vol 36 (1) ◽  
pp. 1-5
Author(s):  
Sławomir Wąsik
Keyword(s):  
Concentration Field ◽  
Laser Interferometry ◽  
Model Systems ◽  
Water Phase ◽  
Biophysical Model ◽  
Diffusion Kinetics ◽  
Interferometric Method ◽  
Interferometry Method ◽  
Laser Interferometric ◽  
Kinetics Of

Abstract In this paper some selected applications of laser interferometry method in studies of biophysical model systems are presented. With the aid of a laser interferometric method, specific experiments were performed, which confirm that the gravitational field significantly modifies the amount of transported substance and affects the concentration profiles as well as the time evolution of the concentration field. The laser interferometry was also used to investigation of diffusion of antibiotics (ciprofloxacin or ampicillin) into the water phase from mixtures of neutral or negatively charged liposomes, and antibiotic-liposome interactions. Differences in the diffusion kinetics of ciprofloxacin and ampicillin from liposomal solutions to the water phase were observed. Moreover, the amount of ampicillin and ciprofloxacin released from the anionic liposomal phase was higher than that from the neutral one.

Continuous Quantitative Monitoring of Mural, Platelet-Dependent, Thrombus Kinetics in the Crushed Rat Femoral Vein

1991 ◽  
Vol 65 (04) ◽  
pp. 425-431 ◽  
Author(s):  
F Stockmans ◽  
H Deckmyn ◽  
J Gruwez ◽  
J Vermylen ◽  
R Acland
Keyword(s):  
Thrombus Formation ◽  
Femoral Vein ◽  
Maximum Size ◽  
Digital Analysis ◽  
Video Recordings ◽  
Quantitative Monitoring ◽  
Set Up ◽  
Kinetics Of ◽  
Quantitative Nature

SummaryA new in vivo method to study the size and dynamics of a growing mural thrombus was set up in the rat femoral vein. The method uses a standardized crush injury to induce a thrombus, and a newly developed transilluminator combined with digital analysis of video recordings. Thrombi in this model formed rapidly, reaching a maximum size 391 ± 35 sec following injury, after which they degraded with a half-life of 197 ± 31 sec. Histological examination indicated that the thrombi consisted mainly of platelets. The quantitative nature of the transillumination technique was demonstrated by simultaneous measurement of the incorporation of 111In labeled platelets into the thrombus. Thrombus formation, studied at 30 min interval in both femoral veins, showed satisfactory reproducibility overall and within a given animalWith this method we were able to induce a thrombus using a clinically relevant injury and to monitor continuously and reproducibly the kinetics of thrombus formation in a vessel of clinically and surgically relevant size

Modelling of impregnation of γ-alumina with cobalt and molybdenum salts. CoCl2-(NH4)2MoO4-γ-Al2O3 (aluminate type) system

1987 ◽  
Vol 52 (3) ◽  
pp. 663-671 ◽  
Author(s):  
Jiří Hanika ◽  
Vladimír Janoušek ◽  
Karel Sporka
Keyword(s):  
Effective Diffusion ◽  
Type System ◽  
Catalyst Particle ◽  
Ammonium Molybdate ◽  
Active Components ◽  
Model Set ◽  
Cobalt Dichloride ◽  
Set Up ◽  
Electron Microanalysis ◽  
Kinetics Of

Adsorption data for the impregnation of alumina with an aqueous solution of cobalt dichloride and ammonium molybdate were treated in terms of the Langmuir adsorption isotherm and compared with a mathematical model set up to describe the kinetics of simultaneous impregnation of a support by two components. The effective diffusion coefficients of the two components at 25 °C in a cylindrical particle of alumina were obtained. The validity of the model used was verified qualitatively by comparing the numerical results with the experimental time dependent concentration profiles of the active components in a catalyst particle, measured by electron microanalysis technique.

Nanoparticle Precipitation in a T-Mixer: Coupling Experimental and Numerical Investigations of the Fluid Dynamics With the Solid Formation Processes

2006 ◽  
Author(s):  
Johannes Gradl ◽  
Florian Schwertfirm ◽  
Hans-Christoph Schwarzer ◽  
Hans-Joachim Schmid ◽  
Michael Manhart ◽  
...  
Keyword(s):  
Flow Field ◽  
Fluid Dynamic ◽  
Concentration Field ◽  
Population Balance ◽  
Mixing Process ◽  
Image Velocimetry ◽  
Modeling Material ◽  
Field Information ◽  
Set Up ◽  
3D Information

Mixing and consequently fluid dynamic is a key parameter to tailor the particle size distribution (PSD) in nanoparticle precipitation. Due to fast and intensive mixing a static T-mixer configuration is capable for synthesizing continuously nanoparticles. The flow and concentration field of the applied mixer is investigated experimentally at different flow rates by Particle Image Velocimetry (PIV) and Laser Induced Fluorescence (LIF). Due to the PIV measurements the flow field in the mixer was characterized qualitatively and the mixing process itself is quantified by the subsequent LIF-measurements. A special feature of the LIF set up is to detect structures in the flow field, which are smaller than the Batchelor length. Thereby a detailed insight into the mixing process in a static T-Mixer is given. In this study a CFD-based approach using Direct Numerical Simulation (DNS) in combination with the solid formation kinetics solving population balance equations (PBE) is applied, using barium sulfate as modeling material. A Lagrangian Particle Tracking strategy is used to couple the flow field information with a micro mixing model and with the classical theory of nucleation. We found that the DNS-PBE approach including macro and micro mixing, combined with the population balance is capable of predicting the full PSD in nanoparticle precipitation for different operating parameters. Additionally to the resulting PSD, this approach delivers a 3D-information about all running subprocesses in the mixer, i.e. supersaturation built-up or nucleation, which is visualized for different process variables.

Kinetics of Plasmon-Driven Hydrosilylation of Silicon Surfaces: Photogenerated Charges Drive Silicon- Carbon Bond Formation

2021 ◽  
Author(s):  
Chengcheng Rao ◽  
Brian Olsen ◽  
Erik Luber ◽  
Jillian Buriak
Keyword(s):  
Green Light ◽  
Kinetic Studies ◽  
Silicon Surfaces ◽  
Moderate Intensity ◽  
Carbon Bond ◽  
Silicon Carbon ◽  
Set Up ◽  
Kinetics Of ◽  
Insight Into

Optically transparent PDMS stamps coated with a layer of gold nanoparticles were employed as plasmonic stamps to drive surface chemistry on silicon surfaces. Illumination of a sandwich of plasmonic stamps, an alkene ink, and hydride-terminated silicon with green light of moderate intensity drives hydrosilylation on the surface. The key to the mechanism of the hydrosilylation is the presence of holes at the Si-H-terminated interface, which is followed by attack by a proximal alkene and formation of the silicon-carbon bond. In this work, detailed kinetic studies of the hydrosilylation on silicon with different doping levels, n++, p++, n, p, and intrinsic were carried out to provide further insight into the role of the metal-insulator-semiconductor (MIS) junction that is set up during the stamping.

scholarly journals The Role of Gravity in the Evolution of the Concentration Field in the Electrochemical Membrane Cell

Entropy ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 680 ◽  
Author(s):  
Kornelia M. Batko ◽  
Andrzej Ślęzak ◽  
Wioletta M. Bajdur
Keyword(s):  
Boundary Layers ◽  
Concentration Polarization ◽  
Concentration Field ◽  
Membrane System ◽  
Volume Transport ◽  
Cellulose Acetate Membrane ◽  
Concentration Boundary ◽  
Concentration Boundary Layers ◽  
Mechanical Stirring

The subject of the study was the osmotic volume transport of aqueous CuSO4 and/or ethanol solutions through a selective cellulose acetate membrane (Nephrophan). The effect of concentration of solution components, concentration polarization of solutions and configuration of the membrane system on the value of the volume osmotic flux ( J v i r ) in a single-membrane system in which the polymer membrane located in the horizontal plane was examined. The investigations were carried out under mechanical stirring conditions of the solutions and after it was turned off. Based on the obtained measurement results J v i r , the effects of concentration polarization, convection polarization, asymmetry and amplification of the volume osmotic flux and the thickness of the concentration boundary layers were calculated. Osmotic entropy production was also calculated for solution homogeneity and concentration polarization conditions. Using the thickness of the concentration boundary layers, critical values of the Rayleigh concentration number ( R C r ), i.e., the switch, were estimated between two states: convective (with higher J v i r ) and non-convective (with lower J v i r ). The operation of this switch indicates the regulatory role of earthly gravity in relation to membrane transport.

Concentration profiles in the electrodeposition of copper ferrocyanide by laser interferometry

1987 ◽  
Vol 65 (9) ◽  
pp. 2009-2012 ◽  
Author(s):  
R. N. O'Brien ◽  
K. S. V. Santhanam
Keyword(s):  
Laser Interferometry ◽  
Potassium Ferrocyanide ◽  
Slow Rotation ◽  
Concentration Profiles ◽  
Cupric Ion ◽  
Beam Laser ◽  
Paramagnetic Solution ◽  
Initial Resistance ◽  
Molecular Layers ◽  
Precipitate Layer

The electrodeposition of cupric ferrocyanide from a solution of potassium ferrocyanide with the convection-free parallel plane horizontal electrodes with the cathode over the anode was followed by multiple beam laser interferometry as well as the conventional electrochemical instrumentation. It is considered that the cupric ion generated immediately reacts with ferrocyanide ion to form a conducting adhering precipitate layer. The initial resistance of this layer is low. Its resistance is constant with thickness until about 5 × 10−8 C mm2 has been passed probably representing ~105 molecular layers when the resistance begins to rise. A magnetic field of 0.47 T caused a slight decrease in the resistance of the cell probably due to slow rotation of the inhomogeneous paramagnetic solution. This coating may be useful as an electrode.

Hydriding and Dehydriding Characteristics of As-Spun Nanocrystalline and Amorphous Mg20Ni10-xMnx (x = 0-4) Alloys

2011 ◽  
Vol 347-353 ◽  
pp. 3420-3424
Author(s):  
Yang Huan Zhang ◽  
Xiao Gang Liu ◽  
Le Le Chen ◽  
Hui Ping Ren ◽  
Guo Fang Zhang ◽  
...  
Keyword(s):  
Amorphous Phase ◽  
Hydrogen Absorption ◽  
Melt Spinning ◽  
Hydrogen Desorption ◽  
Absorption Capacity ◽  
Desorption Kinetics ◽  
Nanocrystalline And Amorphous ◽  
Cast Alloys ◽  
Mn Content ◽  
Kinetics Of

The nanocrystalline and amorphous Mg2Ni-type Mg20Ni10-xMnx (x = 0, 1, 2, 3, 4) alloys were synthesized by melt-spinning technique. The structures of the as-cast and spun alloys were characterized by XRD, SEM and HRTEM. The hydrogen absorption and desorption kinetics of the alloys were measured. The results show that the substitution of Mn for Ni, instead of changing the major phase Mg2Ni, leads to the formation of Mg and MnNi phases. No amorphous phase is detected in the as-spun Mn-free alloy, but the as-spun alloys substituted by Mn display the presence of an amorphous phase, suggesting that the substitution of Mn for Ni enhances the glass forming ability of the Mg2Ni-type alloy. The hydrogen absorption capacity of the as-cast alloys first increases and then decreases with the variation of the amount of Mn substitution. The hydrogen desorption capacity of the alloys markedly increases with growing Mn content.

Electro-initiated cationic polymerization in the presence of potassium hexafluoroantimonate

RSC Advances ◽  
2014 ◽  
Vol 4 (42) ◽  
pp. 22224-22229 ◽  
Author(s):  
Feng Yang ◽  
Xiaoqun Zhu ◽  
Chunguang Li ◽  
Jinliang Yang ◽  
Jeffery W. Stansbury ◽  
...  
Keyword(s):  
Real Time ◽  
Cationic Polymerization ◽  
Real Time Monitoring ◽  
Vinyl Ethers ◽  
Set Up ◽  
Kinetics Of

The kinetics of electro-initiated polymerization of vinyl ethers in the presence of potassium hexafluoroantimonate are investigated by RT-FT-NIR. The apparatus for real time monitoring of the kinetics of the reaction is set up by using ITO conductive glasses. Potassium hexafluoroantimonate has been proven to be an efficient initiator for electro-initiated polymerization of vinyl ethers.

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