A relationship between diffusivity and cooperativity of supercooled liquids in the proximity of glass transition

Zada

Asia-Pacific J Chem Eng

et al. 2020

The recycling of chemical containing glass bottles is generally not recommended due to high health risk. In this study, used glass ampoules were devitrified into a porous material by coprocessing with eggshells, salt, and soda at different temperatures. In this thermochemical reaction, eggshells decomposed into calcium, porogenic gases, and char. The calcium worked as a flux in the reaction while char and gases promoted the porosity of the devitrified glass. The thermochemically processed glass was treated with deionized water to clear the water‐soluble fractions and to improve the surface porosity. The final product was characterized for its chemical composition, functional groups, surface morphology, and pore sizes. The porous product revealed the pore volume of .010 cc/g, surface area of 32.0399 m2/g and pore radius of 1.522 nm. The well‐known Freundlich and Longmuir models were used to investigate the adsorption of blue dye onto the prepared porous glass adsorbent. The adsorbed amount of dye was found influenced by the contact time, adsorbent dose, pH of solution, and dye concentration. The porous glass adsorbed about 2.788 mg/g of dye at pH 2, which decreased to 1.938 mg/g at pH 7. The dye adsorption data followed the best fit for Freundlich model as compared to the Longmuir model.

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Preparation of activated porous glass adsorbent through thermochemical reforming of ampoules and eggshells for remediation of direct blue dye pollution

Zada

Asia-Pacific J Chem Eng

et al. 2020

“…The above discussion indicates that the cooperativity NB is related intimately to the transport properties such as diffusion and ionic conduction. Analytical expression for the cooperativity has been also obtained in terms of the parameter of the BSCNF model [39]. Therefore, we can say that our model provides a good reference for understanding the complex atomic and molecular dynamics occurring in real systems.…”

Section: Model Of Non-arrhenius Ionic Conductivitymentioning

confidence: 94%

“…Above, we focused on the description of the non-Arrhenius temperature dependence of the ionic conductivity in solids. A similar expression to that shown in Equation (5) was also used to analyze the conductivity and diffusivity behavior of liquid systems [39,40]. However, for this case, the Stokes–Einstein relation that connects conductivity to viscosity was used.…”

Section: Model Of Non-arrhenius Ionic Conductivitymentioning

confidence: 99%

A Model for Non-Arrhenius Ionic Conductivity

Aniya

Ikeda

2019

Nanomaterials

Self Cite

Non-Arrhenius ionic conductivity is observed in various solid electrolytes. The behavior is intriguing, because it limits the magnitude of ionic conductivity at high temperatures. Understanding the nature of this behavior is of fundamental interest and deserves attention. In the present study, the temperature dependence of the ionic conductivity in solids and liquids is analyzed using the Bond Strength–Coordination Number Fluctuation (BSCNF) model developed by ourselves. It is shown that our model describes well the temperature dependence of ionic conductivity that varies from Arrhenius to non-Arrhenius-type behavior. According to our model, the non-Arrhenius behavior is controlled by the degree of binding energy fluctuation between the mobile species and the surroundings. A brief discussion on a possible size effect in non-Arrhenius behavior is also given. Within the available data, the BSCNF model suggests that the size effect in the degree of the non-Arrhenius mass transport behavior in a poly (methyl ethyl ether)/polystyrene (PVME/PS) blend is different from that in a-polystyrene and polyamide copolymer PA66/6I.

“…In other words, it gives a measure on the degree of coupling between diffusion and viscous flow. In a recent study, the relation between diffusivity and cooperativity of different supercooled liquids near Tg have been analyzed in the framework of the BSCNF model [26,27]. As shown in Fig.…”

Section: Cooperativity and Fractional Stokes-einstein Relationmentioning

confidence: 99%

Analysis of Cooperativity in Metallic Glass Forming Liquids

Aniya

Ikeda

2014

MSF

Self Cite

The relation between fragility and cooperativity of atomic motion in bulk metallic glass forming liquids is studied based on the bond strength-coordination number fluctuation model. The model describes the temperature dependence of the viscosity in terms of the mean values of the bond strength, coordination number and their fluctuations of the structural units that form the melt. According to the model, the cooperativity increases with the increase of fragility. The model estimates that the magnitude of the cooperativityNBextends approximately from 7 to 60 structural units, depending on the material. The temperature dependence ofNBfor different metallic glass forming systems reveals thatNBincreases with the decrease of temperature. The relation betweenNBand diffusivity of atoms is discussed briefly.