FG Keramische Werkstoffe

35 Items

Recent Submissions
3D Printing for Soft Tissue Regeneration and Applications in Medicine

Pantermehl, Sven ; Emmert, Steffen ; Foth, Aenne ; Grabow, Niels ; Alkildani, Said ; Bader, Rainer ; Barbeck, Mike ; Jung, Ole (2021-03-26)

The use of additive manufacturing (AM) technologies is a relatively young research area in modern medicine. This technology offers a fast and effective way of producing implants, tissues, or entire organs individually adapted to the needs of a patient. Today, a large number of different 3D printing technologies with individual application areas are available. This review is intended to provide ...

The Early Fragmentation of a Bovine Dermis-Derived Collagen Barrier Membrane Contributes to Transmembraneous Vascularization—A Possible Paradigm Shift for Guided Bone Regeneration

Kapogianni, Eleni ; Alkildani, Said ; Radenkovic, Milena ; Xiong, Xin ; Krastev, Rumen ; Stöwe, Ignacio ; Bielenstein, James ; Jung, Ole ; Najman, Stevo ; Barbeck, Mike ; Rothamel, Daniel (2021-03-09)

Collagen-based barrier membranes are an essential component in Guided Bone Regeneration (GBR) procedures. They act as cell-occlusive devices that should maintain a micromilieu where bone tissue can grow, which in turn provides a stable bed for prosthetic implantation. However, the standing time of collagen membranes has been a challenging area, as native membranes are often prematurely resorbed...

Silicate dielectric ceramics for millimetre wave applications

Kamutzki, Franz ; Schneider, Sven ; Barowski, Jan ; Gurlo, Aleksander ; Hanaor, Dorian A.H. (2021-03-02)

Silicate ceramics are of considerable promise as high frequency dielectrics in emerging millimetre wave applications including high bandwidth wireless communication and sensing. In this review, we show how high quality factors and low, thermally stable permittivities arise in ordered silicate structures. On the basis of a large number of existing studies, the dielectric performance of silicate ...

Cu-modified SrTiO3 perovskites toward enhanced water–gas shift catalysis: A combined experimental and computational study

Coletta, Vitor C. ; Gonçalves, Renato V. ; Bernardi, Maria I. B. ; Hanaor, Dorian A. H. ; Assadi, M. Hussein N. ; Marcos, Francielle C. F. ; Nogueira, Francisco G. E. ; Assaf, Elisabete M. ; Mastelaro, Valmor R. (2020-12-23)

A water–gas shift reaction (WGS) is important and widely applied in the production of H2. Cu-modified perovskites are promising catalysts for WGS reactions in hydrogen generation. However, the structure-dependent stability and reaction pathways of such materials remain unclear. Herein, we report catalytically active Cu-modified SrTiO3 (nominally SrTi1–xCuxO3) prepared by a modified polymeric pr...

Biocompatibility and Immune Response of a Newly Developed Volume-Stable Magnesium-Based Barrier Membrane in Combination with a PVD Coating for Guided Bone Regeneration (GBR)

Steigmann, Larissa ; Jung, Ole ; Kieferle, Wolfgang ; Stojanovic, Sanja ; Proehl, Annica ; Görke, Oliver ; Emmert, Steffen ; Najman, Stevo ; Barbeck, Mike ; Rothamel, Daniel (2020-12-20)

To date, there are no bioresorbable alternatives to non-resorbable and volume-stable membranes in the field of dentistry for guided bone or tissue regeneration (GBR/GTR). Even magnesium (Mg) has been shown to constitute a favorable biomaterial for the development of stabilizing structures. However, it has been described that it is necessary to prevent premature degradation to ensure both the fu...

Efficient NO2 sensing performance of a low-cost nanostructured sensor derived from molybdenite concentrate

Hojamberdiev, Mirabbos ; Goel, Neeraj ; Kumar, Rahul ; Kadirova, Zukhra C. ; Kumar, Mahesh (2020-09-07)

Accumulation of industrial solid waste necessitates the development of utilization processes and technologies to reduce their negative environmental impact. Herein, molybdenite concentrate from the mining-metallurgy industry is systematically characterized as a valuable starting material for the fabrication of an efficient and low-cost nanostructured gas sensor. Few-layer MoS2 is obtained from ...

Low-temperature fluoride-assisted synthesis of mullite whiskers

Abdullayev, Amanmyrat ; Zemke, Fabian ; Gurlo, Aleksander ; Bekheet, Maged F. (2020-08-24)

Mullite is a promising material for advanced ceramic applications. The synthesis of mullite from oxides requires very high temperatures (T > 1000 °C). Here highly crystalline mullite whiskers with an average length and diameter of 2.37 ± 1.7 μm and 0.18 ± 0.11 μm, respectively, were synthesized by a fluoride-assisted method from aluminium sulfate, aluminium fluoride and fumed silica at a temper...

Sintering of ceramics for clay in situ resource utilization on Mars

Karl, David ; Kamutzki, Franz ; Lima, Pedro ; Gili, Albert ; Duminy, Thomas ; Zocca, Andrea ; Günster, Jens ; Gurlo, Aleksander (2020-06-27)

The sintering of wet processed Mars global simulant green bodies is explored. Green bodies shaped using slip casting, throwing on a potter’s wheel and additive manufacturing, including material extrusion (robocasting) and layerwise slurry deposition (LSD) are sintered in terrestrial and simulated Mars atmosphere. A sintering schedule is developed using hot stage microscopy, water absorption, si...

Universality of the emergent scaling in finite random binary percolation networks

Zhai, Chongpu ; Hanaor, Dorian ; Gan, Yixiang (2017-02-16)

In this paper we apply lattice models of finite binary percolation networks to examine the effects of network configuration on macroscopic network responses. We consider both square and rectangular lattice structures in which bonds between nodes are randomly assigned to be either resistors or capacitors. Results show that for given network geometries, the overall normalised frequency-dependent ...

Fabrication and Characterization of Ice Templated Membrane Supports from Portland Cement

Abdullayev, Amanmyrat ; Kamm, Paul H. ; Bekheet, Maged F. ; Gurlo, Aleksander (2020-05-09)

Porous ceramic membranes for aqueous microfiltration and ultrafiltration processes suffer from the high-costs of material and processing. The latter is mainly due to the high-temperature sintering step. In this work, cement-based membrane supports from ultrafine Portland cement are studied as a low-cost alternative to traditional oxidic ceramic supports. An environmentally friendly freeze-casti...

Highly efficient catalytic pyrolysis of polyethylene waste to derive fuel products by novel polyoxometalate/kaolin composites

Attique, Saira ; Batool, Madeeha ; Yaqub, Mustansara ; Goerke, Oliver ; Gregory, Duncan H. ; Shah, Asma Tufail (2020-02-06)

We report here alumina-substituted Keggin tungstoborate/kaolin clay composite materials (KAB/kaolin) as polyethylene cracking catalysts. KAB/kaolin composites with varying concentrations of KAB (10–50 wt.%) were synthesized by the wet impregnation method and successfully characterized by Fourier-transform infrared spectroscopy, powder X-ray diffraction, thermo-gravimetric analysis and scanning ...

Fabrication, in vitro and in vivo studies of bilayer composite membrane for periodontal guided tissue regeneration

Zahid, Saba ; Khan, Abdul Samad ; Chaudhry, Aqif Anwar ; Ghafoor, Sarah ; Ain, Qurat Ul ; Raza, Ahtasham ; Rahim, Muhammad Imran ; Görke, Oliver ; Rehman, Ihtesham Ur ; Tufail, Asma (2018-12-03)

Development of a guided occlusive biodegradable membrane with controlled morphology in order to restrict the ingrowth of epithelial cells is still a challenge in dental tissue engineering. A bilayer membrane with a non-porous upper layer (polyurethane) and porous lower layer (polycaprolactone and bioactive glass composite) with thermoelastic properties to sustain surgery treatment was developed...

Carbide-Modified Pd on ZrO2 as Active Phase for CO2-Reforming of Methane—A Model Phase Boundary Approach

Köpfle, Norbert ; Ploner, Kevin ; Lackner, Peter ; Götsch, Thomas ; Thurner, Christoph ; Carbonio, Emilia ; Hävecker, Michael ; Knop-Gericke, Axel ; Schlicker, Lukas ; Doran, Andrew ; Kober, Delf ; Gurlo, Aleksander ; Willinger, Marc ; Penner, Simon ; Schmid, Michael ; Klötzer, Bernhard (2020-09-02)

Starting from subsurface Zr0-doped “inverse” Pd and bulk-intermetallic Pd0Zr0 model catalyst precursors, we investigated the dry reforming reaction of methane (DRM) using synchrotron-based near ambient pressure in-situ X-ray photoelectron spectroscopy (NAP-XPS), in-situ X-ray diffraction and catalytic testing in an ultrahigh-vacuum-compatible recirculating batch reactor cell. Both intermetallic...

Metal-containing ceramic nanocomposites synthesized from metal acetates and polysilazane

Wang, Jun ; Schölch, Valérie ; Görke, Oliver ; Schuck, Götz ; Wang, Xifan ; Shao, Gaofeng ; Schorr, Susan ; Bekheet, Maged F. ; Gurlo, Aleksander (2020-04-27)

Metal-containing (Mn, Fe, Co, Cu, Zn and Ag) polysilazane precursors are synthesized via one-step chemical reaction of metal acetates with poly(vinyl)silazane (Durazane 1800) at room temperature under argon atmosphere. The ATR-FTIR spectra of the synthesized metal-containing precursors reveal that the metal acetates used in the synthesis catalyze the hydrosilylation reaction between -Si-H and -...

Freeze Casting: From Low‐Dimensional Building Blocks to Aligned Porous Structures—A Review of Novel Materials, Methods, and Applications

Shao, Gaofeng ; Hanaor, Dorian A. H. ; Shen, Xiaodong ; Gurlo, Aleksander (2020-03-12)

Freeze casting, also known as ice templating, is a particularly versatile technique that has been applied extensively for the fabrication of well‐controlled biomimetic porous materials based on ceramics, metals, polymers, biomacromolecules, and carbon nanomaterials, endowing them with novel properties and broadening their applicability. The principles of different directional freeze‐casting pro...

Improved oxidation resistance of high emissivity coatings on fibrous ceramic for reusable space systems

Shao, Gaofeng ; Lu, Yucao ; Hanaor, Dorian A. H. ; Cui, Sheng ; Jiao, Jian ; Shen, Xiaodong (2018-11-13)

To develop high emissivity coatings on fibrous ceramic substrates with improved thermal resistance for reusable space systems, WSi2–MoSi2–Si–SiB6-borosilicate glass coatings were prepared on fibrous ZrO2 by slurry dipping and subsequent high temperature rapid sintering. A coating with 20 wt% WSi2 and 50 wt% MoSi2 presents optimal thermal stability with only 10.06 mg/cm2 mass loss and 4.0% emiss...

On-chip assembly of 3D graphene-based aerogels for chemiresistive gas sensing

Shao, Gaofeng ; Ovsianytskyi, Oleksandr ; Bekheet, Maged F. ; Gurlo, Aleksander (2019-11-29)

Integration of the material preparation step into the device fabrication process is of prime importance for the development of high performance devices. This study presents an innovative strategy for the in situ assembly of graphene-based aerogels on a chip by polymerization–reduction and annealing processes, which are applied as chemiresistive gas sensors for the detection of NO2.

Natural and synthetic apatites as adsorbents for the removal of azo dyes from aqueous solutions

Bensalah, Hiba (2020)

With the rapid growth of society, demand for water has increased tremendously with agricultural, industrial and domestic sectors consuming a big volume of available fresh water, which has resulted in the generation of large amounts of wastewater containing various pollutants. Most of those produced pollutants are dyes, which are discharged directly in aqueous effluents, which poses a serious ha...

Ceria-Based Dual-Phase Membranes for High-Temperature Carbon Dioxide Separation: Effect of Iron Doping and Pore Generation with MgO Template

Gili, Albert ; Bischoff, Benjamin ; Simon, Ulla ; Schmidt, Franziska ; Kober, Delf ; Görke, Oliver ; Bekheet, Maged F. ; Gurlo, Aleksander (2019-08-26)

Dual-phase membranes for high-temperature carbon dioxide separation have emerged as promising technology to mitigate anthropogenic greenhouse gases emissions, especially as a pre- and post-combustion separation technique in coal burning power plants. To implement these membranes industrially, the carbon dioxide permeability must be improved. In this study, Ce0.8Sm0.2O2−δ (SDC) and Ce0.8Sm0.19Fe...

High-temperature separation and activation of carbon dioxide by dual-phase membranes and nickel catalysts

Gili de Villasante, Albert (2020)

Carbon dioxide emission mitigation arises as one of the critical challenges for sustainable development and to minimize the negative effects of climate change. Dual-phase (DP) membranes for high-temperature separation of carbon dioxide have been suggested as potential post-combustion capture technology in fossil fuel power plants. Once separated, carbon dioxide can be converted to valuable chem...