scholarly journals Preparation of Hydrogen Electrodes of Solid Oxide Cells by Infiltration: Effects of the Preparation Procedure on the Resulting Microstructure

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 131 ◽  
Author(s):  
Bartosz Hołówko ◽  
Jakub Karczewski ◽  
Sebastian Molin ◽  
Piotr Jasiński
Keyword(s):  
Porous Scaffold ◽  
Complex Structure ◽  
Solid Oxide ◽  
Homogeneous Material ◽  
Porous Scaffolds ◽  
Functional Layer ◽  
Time Profiles ◽  
Supporting Layer ◽  
Infiltration Technique ◽  
Temperature Time

In this work, the infiltration technique was used to produce hydrogen electrodes for solid oxide cells. Different infiltration methodologies were tested in order to try to shorten the infiltration cycle time. The porous scaffolds used for infiltration were based on highly porous yttria-stabilized zirconia (YSZ) obtained by etching the reduced nickel from the Ni-YSZ cermet in HNO3 acid. The support had a complex structure which included a ~130 µm porous functional layer with small pores and a ~320 µm thick supporting layer with large pores. Infiltrations have been carried out using aqueous nickel nitrate solutions. Various infiltration procedures were used, differing in temperature/time profiles. The results show that slow evaporation is crucial for obtaining a homogeneous material distribution leading to high-quality samples. A longer evaporation time promotes the proper distribution of nickel throughout the porous scaffold. The shortening of the heat treatment procedure leads to blockage of the pores and not-uniform nickel distribution.

Effect of an Anode Functional Layer on Cell Performance of Anode-Supported Solid Oxide Fuel Cells by a Decalcomania Method

2013 ◽  
Vol 51 (2) ◽  
pp. 125-130 ◽  
Author(s):  
Sun-Min Park ◽  
Hae-Ran Cho ◽  
Byung-Hyun Choi ◽  
Yong-Tae An ◽  
Ja-Bin Koo ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide ◽  
Cell Performance ◽  
Oxide Fuel ◽  
Functional Layer

Fabrication of poly (1, 8-octanediol-co-Pluronic F127 citrate)/chitin nanofibril/bioactive glass (POFC/ChiNF/BG) porous scaffold via directional-freeze-casting

2020 ◽  
Vol 40 (7) ◽  
pp. 591-599
Author(s):  
Yaling Tian ◽  
Kai Liang ◽  
Yali Ji
Keyword(s):  
Bioactive Glass ◽  
Porous Structure ◽  
Pore Structure ◽  
Porous Scaffold ◽  
Pluronic F127 ◽  
Porous Scaffolds ◽  
Freeze Casting ◽  
Promising Candidate ◽  
Complete Replacement

AbstractThe citrate-based thermoset elastomer is a promising candidate for bone scaffold material, but the harsh curing condition made it difficult to fabricate porous structure. Recently, poly (1, 8-octanediol-co-Pluronic F127 citrate) (POFC) porous scaffold was creatively fabricated by chitin nanofibrils (ChiNFs) supported emulsion-freeze-casting. Thanks to the supporting role of ChiNFs, the lamellar pore structure formed by directional freeze-drying was maintained during the subsequent thermocuring. Herein, bioactive glass (BG) was introduced into the POFC porous scaffolds to improve bioactivity. It was found the complete replacement of ChiNF particles with BG particles could not form a stable porous structure; however, existing at least 15 wt% ChiNF could ensure the formation of lamellar pore, and the interlamellar distance increased with BG ratios. Thus, the BG granules did not contribute to the formation of pore structure like ChiNFs, however, they surely endowed the scaffolds with enhanced mechanical properties, improved osteogenesis bioactivity, better cytocompatibility as well as quick degradation rate. Reasonably adjusting BG ratios could balance the requirements of porous structure and bioactivity.

Improvement of output performance of solid oxide fuel cell by optimizing Ni/samaria-doped ceria anode functional layer

2008 ◽  
Vol 185 (1) ◽  
pp. 153-158 ◽  
Author(s):  
Na Ai ◽  
Zhe Lü ◽  
Jinke Tang ◽  
Kongfa Chen ◽  
Xiqiang Huang ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Doped Ceria ◽  
Oxide Fuel ◽  
Functional Layer ◽  
Output Performance

scholarly journals Porous Geometry Guided Micro-mechanical Environment Within Scaffolds for Cell Mechanobiology Study in Bone Tissue Engineering

2021 ◽  
Vol 9 ◽  
Author(s):  
Feihu Zhao ◽  
Yi Xiong ◽  
Keita Ito ◽  
Bert van Rietbergen ◽  
Sandra Hofmann
Keyword(s):  
Porous Scaffold ◽  
Mechanical Strain ◽  
Three Dimensional ◽  
Pore Geometry ◽  
Cell Physiology ◽  
Porous Scaffolds ◽  
Mechanical Environment ◽  
Functional Features ◽  
Future Work

Mechanobiology research is for understanding the role of mechanics in cell physiology and pathology. It will have implications for studying bone physiology and pathology and to guide the strategy for regenerating both the structural and functional features of bone. Mechanobiological studies in vitro apply a dynamic micro-mechanical environment to cells via bioreactors. Porous scaffolds are commonly used for housing the cells in a three-dimensional (3D) culturing environment. Such scaffolds usually have different pore geometries (e.g. with different pore shapes, pore dimensions and porosities). These pore geometries can affect the internal micro-mechanical environment that the cells experience when loaded in the bioreactor. Therefore, to adjust the applied micro-mechanical environment on cells, researchers can tune either the applied load and/or the design of the scaffold pore geometries. This review will provide information on how the micro-mechanical environment (e.g. fluid-induced wall shear stress and mechanical strain) is affected by various scaffold pore geometries within different bioreactors. It shall allow researchers to estimate/quantify the micro-mechanical environment according to the already known pore geometry information, or to find a suitable pore geometry according to the desirable micro-mechanical environment to be applied. Finally, as future work, artificial intelligent – assisted techniques, which can achieve an automatic design of solid porous scaffold geometry for tuning/optimising the micro-mechanical environment are suggested.

scholarly journals Synthesis of 3D-porous scaffold from cockle shells waste-based hydroxyapatite with addition silica from tin tailings

2021 ◽  
Vol 926 (1) ◽  
pp. 012044
Author(s):  
F Afriani ◽  
J Evi. ◽  
R A Rafsanjani ◽  
R Amelia ◽  
M Hudatwi ◽  
...  
Keyword(s):  
Diffraction Pattern ◽  
Goodness Of Fit ◽  
Porous Scaffold ◽  
Raw Materials ◽  
Synthesis Method ◽  
Decomposition Temperature ◽  
Porous Scaffolds ◽  
Xrd Pattern ◽  
Replication Method ◽  
Tailings Sand

Abstract This study aims to synthesize a porous scaffold based on hydroxyapatite and silica using the polymer sponge replication method. In bone tissue engineering technology, the development of porous scaffolds is a topic that is intensively studied because it is expected to be a solution to various problems of conventional bone therapy. In addition to proposing a porous scaffold synthesis method, we also utilize natural waste-based materials such as cockle shells and tin tailings as raw materials in this research. Investigation through x-ray diffraction (XRD) pattern with the goodness of fit coefficient, X 2 = 0.09 shows that the coprecipitation method is effective for the synthesis of hydroxyapatite. Analysis of XRD pattern of tin tailings sand with a value of X 2 = 0.008 showed that the diffraction pattern was related to silica with space group P 41 21 2. The polymer sponge replication method with polyurethane template succeeded in obtaining scaffolds with macropores above 300 μm. Based on the diffraction pattern of the three porous scaffolds prepared with different percentages of HA, it is known that all porous scaffolds have peaks related to HA and silica. It indicates that the decomposition temperature of polymer does not provide sufficient energy for the HA and silica to transform or react chemically.

scholarly journals In Vivo Vascularization of Anisotropic Channeled Porous Polylactide-Based Capsules for Islet Transplantation: The Effects of Scaffold Architecture and Implantation Site

2015 ◽  
pp. S75-S84 ◽  
Author(s):  
N. KASOJU ◽  
D. KUBIES ◽  
E. FÁBRYOVÁ ◽  
J. KŘÍŽ ◽  
M. M. KUMOREK ◽  
...  
Keyword(s):  
Islet Transplantation ◽  
Porous Scaffold ◽  
Oxygen Demand ◽  
Inflammatory Cells ◽  
Host Cells ◽  
Cell Infiltration ◽  
Greater Omentum ◽  
Brown Norway ◽  
Porous Scaffolds

The replacement of pancreatic islets for the possible treatment of type 1 diabetes is limited by the extremely high oxygen demand of the islets. To this end, here we hypothesize to create a novel extra-hepatic highly-vascularized bioartificial cavity using a porous scaffold as a template and using the host body as a living bioreactor for subsequent islet transplantation. Polylactide-based capsular-shaped anisotropic channeled porous scaffolds were prepared by following the unidirectional thermally-induced phase separation technique, and were implanted under the skin and in the greater omentum of Brown Norway rats. Polyamide mesh-based isotropic regular porous capsules were used as the controls. After 4weeks, the implants were excised and analyzed by histology. The hematoxylin and eosin, as well as Masson's trichrome staining, revealed a) low or no infiltration of giant inflammatory cells in the implant, b) minor but insignificant fibrosis around the implant, c) guided infiltration of host cells in the test capsule in contrast to random cell infiltration in the control capsule, and d) relatively superior cell infiltration in the capsules implanted in the greater omentum than in the capsules implanted under the skin. Furthermore, the anti-CD31 immunohistochemistry staining revealed numerous vessels at the implant site, but mostly on the external surface of the capsules. Taken together, the current study, the first of its kind, is a significant step-forward towards engineering a bioartificial microenvironment for the transplantation of islets.

A Model of Tissue Charring During Interstitial Laser Photocoagulation: Estimation of the Char Temperature

1999 ◽  
Author(s):  
William M. Whelan ◽  
Douglas R. Wyman
Keyword(s):  
Laser Photocoagulation ◽  
Continuous Wave ◽  
Laser Energy ◽  
Ex Vivo ◽  
Thermal Gradients ◽  
Tissue Water ◽  
Time Profiles ◽  
Interstitial Laser Photocoagulation ◽  
Interstitial Laser ◽  
Temperature Time

Abstract Interstitial laser photocoagulation (ELP) was performed ex vivo in lean bovine muscle by delivering 1.5 W of continuous-wave 1064 nm Nd:YAG laser energy from a 400 μm core plane-cut optical fiber. The strategy for determining the char temperature involved measuring temperatures where thermal gradients were reduced, and extracting times at which temperature-time profiles displayed interesting nonlinear changes. These times were used to guide a finite difference thermal model, calculating transient temperatures based on two physical descriptions of tissue charring. Modifications in the optical and thermophysical properties due to tissue coagulation (T ≥ 60 °C) and vaporization of tissue water (T ≥ 100°C), respectively, were considered. By placing measured charring dimensions, 2.0 ± 0.3 mm, on calculated temperature-distance profiles, a tissue charring temperature of 414 ± 92°C was estimated.

scholarly journals 3234 Cell Proliferation and Differentiation in 3D printed Polycarbonate Urethane Porous Scaffolds

2019 ◽  
Vol 3 (s1) ◽  
pp. 141-141
Author(s):  
Bijan Abar ◽  
Alejandro Aalleja ◽  
Cambre Kelly ◽  
Natalia Von Windheim ◽  
Jennifer West ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cellular Proliferation ◽  
Porous Scaffold ◽  
Biological Response ◽  
Collagen Gel ◽  
Porous Scaffolds ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Study Population ◽  
3D Printed

OBJECTIVES/SPECIFIC AIMS: The aim of this study is to understand how porosity and collagen filling impact cell proliferation and differentiation in 3D printed scaffolds. METHODS/STUDY POPULATION: 3 groups of scaffolds will be 3D printed using FDM: solid scaffold, porous scaffold and porous scaffold with collagen gel (n=10 for each group) Internal geometries and surface structure will be analyzed using micro CT and Scanning Electron Mi RESULTS/ANTICIPATED RESULTS: We hypothesize that porosity and collagen filler will increase signal from Picogreen assay and ALP assay when normalized to scaffold surface area, indicating enhanced cell proliferation and differentiation. DISCUSSION/SIGNIFICANCE OF IMPACT: 3D printing PCU is a relatively new technique with very little published in the literature. Previous work has focused on the mechanical properties and not the biological response to the polymer. Understanding how to optimize cellular proliferation and differentiation can lead to the development of better implants that will integrate into the host’s structure and facilitate tissue regeneration.

Scalable fabrication process of thin-film solid oxide fuel cells with an anode functional layer design and a sputtered electrolyte

2020 ◽  
Vol 45 (58) ◽  
pp. 33980-33992 ◽  
Author(s):  
Sungmin Kang ◽  
Jaeseok Lee ◽  
Gu Young Cho ◽  
Yusung Kim ◽  
Sanghun Lee ◽  
...  
Keyword(s):  
Thin Film ◽  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide ◽  
Fabrication Process ◽  
Oxide Fuel ◽  
Functional Layer
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