scholarly journals Characterization of the Structure and Transport Properties of Alginate/Chitosan Microparticle Membranes Utilized in the Pervaporative Dehydration of Ethanol

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 411
Author(s):  
Gabriela Dudek ◽  
Przemysław Borys ◽  
Anna Strzelewicz ◽  
Monika Krasowska
Keyword(s):  
Random Walk ◽  
Transport Properties ◽  
Experimental Studies ◽  
Transport Parameters ◽  
Void Space ◽  
Fractal Parameters ◽  
Dehydration Processes ◽  
Average Size ◽  
High Resolution Microscopy

The structure and transport properties of alginate/chitosan microparticle membranes used in ethanol dehydration processes were investigated. The membranes were characterized based on images obtained from high-resolution microscopy. The following parameters were determined: the observed total amount of void space, the average size of the void domains, their length and diameter, the fractal dimension, and the generalized stochastic fractal parameters. The total amount of void space was determined to be between 54% and 64%. The average size of the void domains is smaller for alginate membranes containing neat (CS) and phosphorylated (CS-P) chitosan particles when compared to those membranes filled with glycidol-modified (CS-G) and glutaraldehyde crosslinked (CS-GA) chitosan particles. Furthermore, the transport of ethanol and water particles through the studied membranes was modelled using a random walk framework. It was observed that the results from the theoretical and experimental studies are directly correlated. The smallest values of water to ethanol diffusion coefficient ratios (i.e., 14) were obtained for Alg (sodium alginate) membranes loaded with the CS and CS-P particles, respectively. Significantly larger values (27 and 19) were noted for membranes filled with CS-G and CS-GA particles, respectively. The simulation results show that the size of channels which develop in the alginate matrix is less suited for ethanol molecules compared to water molecules because of their larger size. Such a situation facilitates the separation of water from ethanol. The comparison of the structural analysis of the membranes and random walk simulations allows one to understand the factors that influence the transport phenomena, in the studied membranes, and comment on the effect of the length, diameter, number of channels, and variations in the pore diameters on these transport parameters.

scholarly journals Microscopic Image Segmentation and Morphological Characterization of Novel Chitosan/Silica Nanoparticle/Nisin Films Using Antimicrobial Technique for Blueberry Preservation

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 303
Author(s):  
Rokayya Sami ◽  
Schahrazad Soltane ◽  
Mahmoud Helal
Keyword(s):  
Ph Value ◽  
Silica Nanoparticle ◽  
Morphological Characterization ◽  
Aerobic Bacteria ◽  
Nano Materials ◽  
Elongation At Break ◽  
Stable Suspension ◽  
Average Size ◽  
Material Ductility

In the current work, the characterization of novel chitosan/silica nanoparticle/nisin films with the addition of nisin as an antimicrobial technique for blueberry preservation during storage is investigated. Chitosan/Silica Nanoparticle/N (CH-SN-N) films presented a stable suspension as the surface loads (45.9 mV) and the distribution was considered broad (0.62). The result shows that the pH value was increased gradually with the addition of nisin to 4.12, while the turbidity was the highest at 0.39. The content of the insoluble matter and contact angle were the highest for the Chitosan/Silica Nanoparticle (CH-SN) film at 5.68%. The use of nano-materials in chitosan films decreased the material ductility, reduced the tensile strength and elongation-at-break of the membrane. The coated blueberries with Chitosan/Silica Nanoparticle/N films reported the lowest microbial contamination counts at 2.82 log CFU/g followed by Chitosan/Silica Nanoparticle at 3.73 and 3.58 log CFU/g for the aerobic bacteria, molds, and yeasts population, respectively. It was observed that (CH) film extracted 94 regions with an average size of 449.10, at the same time (CH-SN) film extracted 169 regions with an average size of 130.53. The (CH-SN-N) film presented the best result at 5.19%. It could be observed that the size of the total region of the fruit for the (CH) case was the smallest (1663 pixels), which implied that the fruit lost moisture content. As a conclusion, (CH-SN-N) film is recommended for blueberry preservation to prolong the shelf-life during storage.

Synthesis and characterization of L-threonine ammonium bromide: grown on single crystal with experimental studies on NLO

2021 ◽  
Vol 44 (3) ◽  
Author(s):  
T KALAIARASI ◽  
M SENTHILKUMAR ◽  
S SHANMUGAN ◽  
T JARIN ◽  
V CHITHAMBARAM ◽  
...  
Keyword(s):  
Single Crystal ◽  
Experimental Studies ◽  
Synthesis And Characterization ◽  
Ammonium Bromide

Dynamic Characterization of a Valveless Micropump Considering Entrapped Gas Bubbles

2013 ◽  
Vol 135 (9) ◽  
Author(s):  
Songjing Li ◽  
Jixiao Liu ◽  
Dan Jiang
Keyword(s):  
Numerical Simulation ◽  
Theoretical Model ◽  
Experimental Studies ◽  
Gas Bubbles ◽  
Chamber Pressure ◽  
Dynamic Characterization ◽  
Valveless Micropump ◽  
Performance Deterioration ◽  
Trapped Gas

Unexpected gas bubbles in microfluidic devices always bring the problems of clogging, performance deterioration, and even device functional failure. For this reason, the aim of this paper is to study the characterization variation of a valveless micropump under different existence conditions of gas bubbles based on a theoretical modeling, numerical simulation, and experiment. In the theoretical model, we couple the vibration of piezoelectric diaphragm, the pressure drop of the nozzle/diffuser and the compressibility of working liquid when gas bubbles are entrapped. To validate the theoretical model, numerical simulation and experimental studies are carried out to investigate the variation of the pump chamber pressure influenced by the gas bubbles. Based on the numerical simulation and the experimental data, the outlet flow rates of the micropump with different size of trapped gas bubbles are calculated and compared, which suggests the influence of the gas bubbles on the dynamic characterization of the valveless micropump.

scholarly journals Properties of the high burnup structure in nuclear light water reactor fuel

2017 ◽  
Vol 105 (11) ◽  
Author(s):  
Thierry Wiss ◽  
Vincenzo V. Rondinella ◽  
Rudy J. M. Konings ◽  
Dragos Staicu ◽  
Dimitrios Papaioannou ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Nuclear Fuel ◽  
Experimental Studies ◽  
Fuel Pellet ◽  
Extended Defects ◽  
Safety Margins ◽  
Fission Gas ◽  
High Burnup ◽  
Formed Structure

AbstractThe formation of the high burnup structure (HBS) is possibly the most significant example of the restructuring processes affecting commercial nuclear fuel in-pile. The HBS forms at the relatively cold outer rim of the fuel pellet, where the local burnup is 2–3 times higher than the average pellet burnup, under the combined effects of irradiation and thermo-mechanical conditions determined by the power regime and the fuel rod configuration. The main features of the transformation are the subdivision of the original fuel grains into new sub-micron grains, the relocation of the fission gas into newly formed intergranular pores, and the absence of large concentrations of extended defects in the fuel matrix inside the subdivided grains. The characterization of the newly formed structure and its impact on thermo-physical or mechanical properties is a key requirement to ensure that high burnup fuel operates within the safety margins. This paper presents a synthesis of the main findings from extensive studies performed at JRC-Karlsruhe during the last 25 years to determine properties and behaviour of the HBS. In particular, microstructural features, thermal transport, fission gas behaviour, and thermo-mechanical properties of the HBS will be discussed. The main conclusion of the experimental studies is that the HBS does not compromise the safety of nuclear fuel during normal operations.

Effects of Fe3O4 Nano Particles Addition in High Temperature Superconductor YBa2Cu3O7-δ

2012 ◽  
Vol 501 ◽  
pp. 309-313 ◽  
Author(s):  
Siti Nurdalila Abd-Ghani ◽  
Roslan Abd-Shukor ◽  
Wei Kong
Keyword(s):  
Transport Properties ◽  
Solid State Reaction Method ◽  
Nano Particles ◽  
Magnetic Impurities ◽  
Oxide Powders ◽  
Nano Fe3o4 ◽  
Activated Flux ◽  
Average Size ◽  
Increasing Temperature ◽  
Magnetic Nano Particles

The effects of nano particles Fe3O4 addition on the superconducting and transport properties of YBa2Cu3O7-δ (YBCO) were studied. YBa2Cu3O7-δ superconductor powders were prepared by using high purity oxide powders via solid state reaction method. Nano Fe3O4 with 0.01 – 0.05 wt.% with average size 28 nm was added into YBCO. The transition temperatures (Tc) of the samples were measured by using four point probe method. The critical current (Ic) of the samples has been determined by using the 1 μV/cm criterion from 30 – 77 K. Sample with 0.02 wt.% nano Fe3O4 showed the highest Tc at 87 K. It is interesting to note the same sample also exhibited the highest Jc at 77 K up to 1683 mA/cm2. Nano Fe3O4 has acted as effective flux pinning centers in YBCO. A small amount of nano particles Fe3O4 addition has successfully improved the superconducting and transport properties of YBCO. The excessive addition of nano Fe3O4 (> 0.02 wt.%) suppressed the Tc and Jc. Overall, Jc decreases with increasing temperature (30 – 77 K) as a consequence of thermally activated flux creep. Magnetic impurities normally suppress superconductivity. However, by adding magnetic nano particles, current carrying capacity of superconductors YBCO was enhanced significantly.

Development and Characterization of Quercetin Loaded Nanoparticle for Skin Cancer

2019 ◽  
Vol 32 (1) ◽  
pp. 1-6
Author(s):  
Nikita Verma
Keyword(s):  
Skin Cancer ◽  
Drug Loading ◽  
Quadratic Model ◽  
Precipitation Method ◽  
Dietary Flavonoid ◽  
Ultraviolet Ray ◽  
Average Size ◽  
Different Characteristics ◽  
Polymer Ratio

As a disease skin cancer has obtained different characteristics over the decades. Solar radiation that contains ultraviolet ray is the prime cause of skin cancer. In this present research, the nano-precipitation method was applied for preparing Quercetin loaded Nanoparticle (Qu-Nps) with much enhanced loading properties and improves incorporation of corresponding drugs. At the same time, the Quadratic model that takes help of the Response Surface Method was applied to observe the effects of some specific parameters maintained in the development of nanoparticle. Here, the sonication time was 20 min and delivery system F6 (with Drug: Polymer ratio of 1:45) provided optimum drug entrapment ability which is 70%. The optimized formulation for average size was almost 102.39 ±7.64 nm with zeta potential diameter averaging -28.43mV. Quercetin is a dietary flavonoid possessing multidimensional properties that is used in various other diseases including viral infection, bacterial infection, diabetes mellitus, and cancer. All outcomes support the view that Quercetin loaded nanoparticles (Qu-Nps) has high entrapment and drug loading abilities.

Studies of the Flame Spraying of Polymers

1996 ◽  
Author(s):  
D.J. Varacalle ◽  
K.W. Couch ◽  
V.S. Budinger
Keyword(s):  
Bond Strength ◽  
Combustion Process ◽  
Experimental Studies ◽  
Polymer Coatings ◽  
Flame Spraying ◽  
Knoop Microhardness ◽  
Resultant Coating ◽  
Strength Characterization ◽  
Thermally Sprayed

Abstract Experimental studies of the subsonic combustion process have been conducted in order to determine the quality and economics of polyester, epoxy, urethane, and hybrid polyester-epoxy coatings. Thermally sprayed polymer coatings are of interest to several industries for anti-corrosion applications, including the infrastructural, chemical, automotive, and aircraft industries. Classical experiments were conducted, from which a substantial range of thermal processing conditions and their effect on the resultant coating were obtained. The coatings were characterized and evaluated by a number of techniques, including Knoop microhardness tests, optical metallography, image analysis, and bond strength. Characterization of the coatings yielded thickness, bond strength, hardness, and porosity.

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