scholarly journals Fractal diffusion of silver ions in hollow cylinders with unsmooth inner surface

2019 ◽  
Vol 14 ◽  
pp. 155892501989564
Author(s):  
Ling Lin ◽  
Shao-Wen Yao

This article studies the ion release from an unsmooth inner surface of a hollow fiber. A fractal diffusion model is established using the fractal derivative, and the effect of the fractal dimension on the ion release is elucidated. The present theory provides a theoretical basis for the optimization of a hollow fiber contained silver ions for practical applications.

2020 ◽  
Vol 15 ◽  
pp. 155892502093544
Author(s):  
Ling Lin ◽  
Shao-Wen Yao ◽  
Huigai Li

A food packing system requires an antimicrobial environment with high air permeability to guarantee absolutely both food safety and long and reliable durability. A hollow fiber membrane containing silver ions is the best candidate for this purpose. However, a safe and controllable release process has become a pressing issue in the practical application. Here, we use the predator–prey model to predict the antimicrobial activity of silver ions released from a hollow fiber, and Staphylococcus aureus was applied to the antibacterial experiment. Both theoretical and experimental results show that there are an optimal concentration of the silver ions and an optimal release time. This article sheds a bright light on the design of a new kind of food packing systems using the hollow fiber membrane.


2013 ◽  
Vol 49 (87) ◽  
pp. 10326 ◽  
Author(s):  
Kang Huang ◽  
Ziye Dong ◽  
Qianqian Li ◽  
Wanqin Jin
Keyword(s):  

2021 ◽  
Author(s):  
Mohammad Jahedi ◽  
Bahram Moshfegh

Abstract Transient heat transfer studies of quenching rotary hollow cylinders with in-line and staggered multiple arrays of jets have been carried out experimentally. The study involves three hollow cylinders (Do/d = 12 to 24) with rotation speed 10 to 50 rpm, quenched by subcooled water jets (ΔTsub=50-80 K) with jet flow rate 2.7 to 10.9 L/min. The increase in area-averaged and maximum heat flux over quenching surface (Af) has been observed in the studied multiple arrays with constant Qtotal compared to previous studies. Investigation of radial temperature distribution at stagnation point of jet reveals that the footprint of configuration of 4-row array is highlighted in radial distances near the outer surface and vanishes further down toward the inner surface. The influence of the main quenching parameters on local average surface heat flux at stagnation point is addressed in all the boiling regimes where the result indicates jet flow rate provides strongest effect in all the boiling regimes. Effectiveness of magnitude of maximum heat flux in the boiling curve for the studied parameters is reported. The result of spatial and temporal heat flux by radial conduction in the solid presents projection depth of cyclic variation of surface heat flux in the radial axis as it disappears near inner surface of hollow cylinder. In addition, correlations are proposed for area-averaged Nusselt number as well as average and maximum local heat flux at stagnation point of jet for the in-line and staggered multiple arrays.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Abdussalam Salhin Mohamad Ali ◽  
Norfarhah Abdul Razak ◽  
Ismail Ab Rahman

Sorbent materials based on a hydrazone Schiff base compound, C14H11BrN4O4, were prepared either by immobilizing the ligand into sol-gel (SG1) or bonding to silica (SG2). The sorbent materials were characterized by FT-IR, EDX, SEM, TEM, and TGA. The sorption characteristics of a matrix of eight transition metal ions (Ag+, Cu2+, Co2+, Ni2+, Fe3+, Pb2+, Zn2+, and Mn2+) using batch method were studied. Several key parameters that affected the extraction efficiency such as pH, contact time, metal ions concentration, and gel size (for SGl) were investigated and optimized. Under the optimized conditions, the physically immobilized hydrazone sorbent (SG1) exhibits highest selectivity towards Ag+ions, while the chemically bonded hydrazone sorbent (SG2) exhibits high extraction for all metal ions tested. However, for practical applications such as the removal and preconcentration of Ag+, the physically immobilized sorbent (SG1) is preferred.


2012 ◽  
Vol 409-410 ◽  
pp. 318-328 ◽  
Author(s):  
Lulu Lai ◽  
Jia Shao ◽  
Qinqin Ge ◽  
Zhengbao Wang ◽  
Yushan Yan

2008 ◽  
Vol 15 (4) ◽  
pp. 695-699 ◽  
Author(s):  
F. Maggi

Abstract. The need to assess the three-dimensional fractal dimension of fractal aggregates from the fractal dimension of two-dimensional projections is very frequent in geophysics, soil, and atmospheric sciences. However, a generally valid approach to relate the two- and three-dimensional fractal dimensions is missing, thus questioning the accuracy of the method used until now in practical applications. A mathematical approach developed for application to suspended aggregates made of cohesive sediment is investigated and applied here more generally to Diffusion-Limited Aggregates (DLA) and Cluster-Cluster Aggregates (CCA), showing higher accuracy in determining the three-dimensional fractal dimension compared to the method currently used.


2013 ◽  
Vol 446 ◽  
pp. 59-67 ◽  
Author(s):  
M.J. Gallagher ◽  
H. Huang ◽  
K.J. Schwab ◽  
D.H. Fairbrother ◽  
B. Teychene

2012 ◽  
Vol 441 ◽  
pp. 279-283 ◽  
Author(s):  
Ling Lin ◽  
Yun Neng Chen ◽  
Wen Zhong Gong ◽  
Shan Yuan Wang

This work focuses on antibacterial efficacy and cellular toxicity of PET-based hollow fiber with silver particles incorporated (Ag/PET hollow fiber), which was synthesized by differential pressure method. Escherichia coli (E. coli) were used to investigate the antibacterial capability of Ag/PET hollow fiber with antibacterial kinetics experiments. The antibacterial results demonstrated that Ag/PET hollow fiber had an excellent antibacterial property against E. coli and the efficacy was dependent on several aspects including fiber length, weight and silver content. The cytotoxicity of Ag/PET hollow fibers on WI-38 cells was assessed using Methyl Thiazolyl Tetrazolium (MTT) assay, and the results showed no significant toxicity to WI-38 cells. SEM images of WI-38 cells treated by Ag/PET hollow fibers showed that cells morphology was unaltered in the presence of Ag/PET hollow fiber. However, abnormal size, shrinkage and rounded appearance of cells at higher dose suggested slight toxicity of Ag/PET hollow fiber. Combining the antibacterial and cytotoxic results, it was found that there was a certain concentration of silver ions which can achieve a minimization of cytotoxicity and a maximization of antibacterial efficacy.


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