TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Simonis, Anette
A1  - Ruge, Christian
A1  - Ecken, Holger
A1  - Müller-Veggian, Mattea
A1  - Lüth, Hans
T1  - A (bio-)chemical Field-effect Sensor with Macroporous Si as Substrate Material and a SiO₂ / LPCVD-Si₃N₄ Double Layer as pH Transducer
JF  - Sensors. 2 (2002), H. 1
N2  - Macroporous silicon has been etched from n-type Si, using a vertical etching cell where no rear side contact on the silicon wafer is necessary. The resulting macropores have been characterised by means of Scanning Electron Microscopy (SEM). After etching, SiO₂ was thermally grown on the top of the porous silicon as an insulating layer and Si₃N₄ was deposited by means of Low Pressure Chemical Vapour Deposition (LPCVD) as transducer material to fabricate a capacitive pH sensor. In order to prepare porous biosensors, the enzyme penicillinase has been additionally immobilised inside the porous structure. Electrochemical measurements of the pH sensor and the biosensor with an Electrolyte/Insulator/Semiconductor (EIS) structure have been performed in the Capacitance/Voltage (C/V) and Constant capacitance (ConCap) mode.
Y1  - 2002
SN  - 1424-8220
U6  - https://doi.org/10.3390/s20100011
SP  - 11
EP  - 22
ER  - 
TY  - JOUR
A1  - Oberländer, Jan
A1  - Jildeh, Zaid B.
A1  - Kirchner, Patrick
A1  - Wendeler, Luisa
A1  - Bromm, Alexander
A1  - Iken, Heiko
A1  - Wagner, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Study of Interdigitated Electrode Arrays Using Experiments and Finite Element Models for the Evaluation of Sterilization Processes
JF  - Sensors
N2  - In this work, a sensor to evaluate sterilization processes with hydrogen peroxide vapor has been characterized. Experimental, analytical and numerical methods were applied to evaluate and study the sensor behavior. The sensor set-up is based on planar interdigitated electrodes. The interdigitated electrode structure consists of 614 electrode fingers spanning over a total sensing area of 20 mm2. Sensor measurements were conducted with and without microbiological spores as well as after an industrial sterilization protocol. The measurements were verified using an analytical expression based on a first-order elliptical integral. A model based on the finite element method with periodic boundary conditions in two dimensions was developed and utilized to validate the experimental findings.
Y1  - 2015
U6  - https://doi.org/10.3390/s151026115
SN  - 1424-8220
N1  - This article belongs to the Special Issue "Gas Sensors—Designs and Applications"
VL  - 15
IS  - 10
SP  - 26115
EP  - 26127
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Abbas, Karim
A1  - Balc, Nicolae
A1  - Bremen, Sebastian
A1  - Skupin, Marco
T1  - Crystallization and aging behavior of polyetheretherketone PEEK within rapid tooling and rubber molding
JF  - Journal of Manufacturing and Materials Processing
N2  - In times of short product life cycles, additive manufacturing and rapid tooling are important methods to make tool development and manufacturing more efficient. High-performance polymers are the key to mold production for prototypes and small series. However, the high temperatures during vulcanization injection molding cause thermal aging and can impair service life. The extent to which the thermal stress over the entire process chain stresses the material and whether it leads to irreversible material aging is evaluated. To this end, a mold made of PEEK is fabricated using fused filament fabrication and examined for its potential application. The mold is heated to 200 ◦C, filled with rubber, and cured. A differential scanning calorimetry analysis of each process step illustrates the crystallization behavior and first indicates the material resistance. It shows distinct cold crystallization regions at a build chamber temperature of 90 ◦C. At an ambient temperature above Tg, crystallization of 30% is achieved, and cold crystallization no longer occurs. Additional tensile tests show a decrease in tensile strength after ten days of thermal aging. The steady decrease in recrystallization temperature indicates degradation of the additives. However, the tensile tests reveal steady embrittlement of the material due to increasing crosslinking.
KW  - additive manufacturing
KW  - fused filament fabrication
KW  - crystallization
KW  - polyetheretherketone
KW  - rapid tooling
Y1  - 2022
U6  - https://doi.org/10.3390/jmmp6050093
SN  - 2504-4494
N1  - The article belongs to the Special Issue Advances in Injection Molding: Process, Materials and Applications
VL  - 6
IS  - 5
SP  - 1
EP  - 12
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Koch, Christopher
A1  - Böhnisch, Nils
A1  - Verdonck, Hendrik
A1  - Hach, Oliver
A1  - Braun, Carsten
T1  - Comparison of unsteady low- and mid-fidelity propeller aerodynamic methods for whirl flutter applications
JF  - Applied Sciences
N2  - Aircraft configurations with propellers have been drawing more attention in recent times, partly due to new propulsion concepts based on hydrogen fuel cells and electric motors. These configurations are prone to whirl flutter, which is an aeroelastic instability affecting airframes with elastically supported propellers. It commonly needs to be mitigated already during the design phase of such configurations, requiring, among other things, unsteady aerodynamic transfer functions for the propeller. However, no comprehensive assessment of unsteady propeller aerodynamics for aeroelastic analysis is available in the literature. This paper provides a detailed comparison of nine different low- to mid-fidelity aerodynamic methods, demonstrating their impact on linear, unsteady aerodynamics, as well as whirl flutter stability prediction. Quasi-steady and unsteady methods for blade lift with or without coupling to blade element momentum theory are evaluated and compared to mid-fidelity potential flow solvers (UPM and DUST) and classical, derivative-based methods. Time-domain identification of frequency-domain transfer functions for the unsteady propeller hub loads is used to compare the different methods. Predictions of the minimum required pylon stiffness for stability show good agreement among the mid-fidelity methods. The differences in the stability predictions for the low-fidelity methods are higher. Most methods studied yield a more unstable system than classical, derivative-based whirl flutter analysis, indicating that the use of more sophisticated aerodynamic modeling techniques might be required for accurate whirl flutter prediction.
KW  - Aeroelasticity
KW  - Flutter
KW  - Propeller whirl flutter
KW  - Unsteady aerodynamics
KW  - 1P hub loads
Y1  - 2024
U6  - https://doi.org/10.3390/app14020850
SN  - 2076-3417
VL  - 14
IS  - 2
SP  - 1
EP  - 28
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Butenweg, Christoph
A1  - Rosin, Julia
A1  - Holler, Stefan
T1  - Analysis of cylindrical granular material silos under seismic excitation
JF  - Buildings
N2  - Silos generally work as storage structures between supply and demand for various goods, and their structural safety has long been of interest to the civil engineering profession. This is especially true for dynamically loaded silos, e.g., in case of seismic excitation. Particularly thin-walled cylindrical silos are highly vulnerable to seismic induced pressures, which can cause critical buckling phenomena of the silo shell. The analysis of silos can be carried out in two different ways. In the first, the seismic loading is modeled through statically equivalent loads acting on the shell. Alternatively, a time history analysis might be carried out, in which nonlinear phenomena due to the filling as well as the interaction between the shell and the granular material are taken into account. The paper presents a comparison of these approaches. The model used for the nonlinear time history analysis considers the granular material by means of the intergranular strain approach for hypoplasticity theory. The interaction effects between the granular material and the shell is represented by contact elements. Additionally, soil–structure interaction effects are taken into account.
KW  - granular silo
KW  - earthquake engineering
KW  - hypoplasticity
KW  - nonlinear transient analyses
Y1  - 2017
U6  - https://doi.org/10.3390/buildings7030061
SN  - 2075-5309
VL  - 7
IS  - 3
SP  - 1
EP  - 12
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Luft, Angela
A1  - Bremen, Sebastian
A1  - Luft, Nils
T1  - A cost/benefit and flexibility evaluation framework for additive technologies in strategic factory planning
JF  - Processes
N2  - There is a growing demand for more flexibility in manufacturing to counter the volatility and unpredictability of the markets and provide more individualization for customers. However, the design and implementation of flexibility within manufacturing systems are costly and only economically viable if applicable to actual demand fluctuations. To this end, companies are considering additive manufacturing (AM) to make production more flexible. This paper develops a conceptual model for the impact quantification of AM on volume and mix flexibility within production systems in the early stages of the factory-planning process. Together with the model, an application guideline is presented to help planners with the flexibility quantification and the factory design process. Following the development of the model and guideline, a case study is presented to indicate the potential impact additive technologies can have on manufacturing flexibility Within the case study, various scenarios with different production system configurations and production programs are analyzed, and the impact of the additive technologies on volume and mix flexibility is calculated. This work will allow factory planners to determine the potential impacts of AM on manufacturing flexibility in an early planning stage and design their production systems accordingly.
KW  - additive manufacturing
KW  - factory planning
KW  - manufacturing flexibility
KW  - volume flexibility
KW  - mix flexibility
Y1  - 2023
U6  - https://doi.org/10.3390/pr11071968
SN  - 2227-9717
VL  - 11
IS  - 7
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Hoffstadt, Kevin
A1  - Cheenakula, Dheeraja
A1  - Nikolausz, Marcell
A1  - Krafft, Simone
A1  - Harms, Hauke
A1  - Kuperjans, Isabel
T1  - Design and construction of a new reactor for flexible biomethanation of hydrogen
JF  - Fermentation
N2  - The increasing share of renewable electricity in the grid drives the need for sufficient storage capacity. Especially for seasonal storage, power-to-gas can be a promising approach. Biologically produced methane from hydrogen produced from surplus electricity can be used to substitute natural gas in the existing infrastructure. Current reactor types are not or are poorly optimized for flexible methanation. Therefore, this work proposes a new reactor type with a plug flow reactor (PFR) design. Simulations in COMSOL Multiphysics ® showed promising properties for operation in laminar flow. An experiment was conducted to support the simulation results and to determine the gas fraction of the novel reactor, which was measured to be 29%. Based on these simulations and experimental results, the reactor was constructed as a 14 m long, 50 mm diameter tube with a meandering orientation. Data processing was established, and a step experiment was performed. In addition, a kLa of 1 h−1 was determined. The results revealed that the experimental outcomes of the type of flow and gas fractions are in line with the theoretical simulation. The new design shows promising properties for flexible methanation and will be tested.
KW  - methanation
KW  - plug flow reactor
KW  - bubble column
KW  - bio-methane
KW  - power-to-gas
Y1  - 2023
U6  - https://doi.org/10.3390/fermentation9080774
SN  - 2311-5637
N1  - The article belongs to the Special Issue Fermentation Processes: Modeling, Optimization and Control
VL  - 9
IS  - 8
SP  - 1
EP  - 16
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Bung, Daniel Bernhard
A1  - Valero, Daniel
T1  - Re-aeration on stepped spillways with special consideration of entrained and entrapped air
JF  - Geosciences
N2  - As with most high-velocity free-surface flows, stepped spillway flows become self-aerated when the drop height exceeds a critical value. Due to the step-induced macro-roughness, the flow field becomes more turbulent than on a similar smooth-invert chute. For this reason, cascades are oftentimes used as re-aeration structures in wastewater treatment. However, for stepped spillways as flood release structures downstream of deoxygenated reservoirs, gas transfer is also of crucial significance to meet ecological requirements. Prediction of mass transfer velocities becomes challenging, as the flow regime differs from typical previously studied flow conditions. In this paper, detailed air-water flow measurements are conducted on stepped spillway models with different geometry, with the aim to estimate the specific air-water interface. Re-aeration performances are determined by applying the absorption method. In contrast to earlier studies, the aerated water body is considered a continuous mixture up to a level where 75% air concentration is reached. Above this level, a homogenous surface wave field is considered, which is found to significantly affect the total air-water interface available for mass transfer. Geometrical characteristics of these surface waves are obtained from high-speed camera investigations. The results show that both the mean air concentration and the mean flow velocity have influence on the mass transfer. Finally, an empirical relationship for the mass transfer on stepped spillway models is proposed.
Y1  - 2018
SN  - 2076-3263
VL  - 8
IS  - 9
SP  - Article number 333
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Bhattarai, Aroj
A1  - May, Charlotte Anabell
A1  - Staat, Manfred
A1  - Kowalczyk, Wojciech
A1  - Tran, Thanh Ngoc
T1  - Layer-specific damage modeling of porcine large intestine under biaxial tension
JF  - Bioengineering
N2  - The mechanical behavior of the large intestine beyond the ultimate stress has never been investigated. Stretching beyond the ultimate stress may drastically impair the tissue microstructure, which consequently weakens its healthy state functions of absorption, temporary storage, and transportation for defecation. Due to closely similar microstructure and function with humans, biaxial tensile experiments on the porcine large intestine have been performed in this study. In this paper, we report hyperelastic characterization of the large intestine based on experiments in 102 specimens. We also report the theoretical analysis of the experimental results, including an exponential damage evolution function. The fracture energies and the threshold stresses are set as damage material parameters for the longitudinal muscular, the circumferential muscular and the submucosal collagenous layers. A biaxial tensile simulation of a linear brick element has been performed to validate the applicability of the estimated material parameters. The model successfully simulates the biomechanical response of the large intestine under physiological and non-physiological loads.
KW  - biaxial tensile experiment
KW  - anisotropy
KW  - hyperelastic
KW  - constitutive modeling
KW  - damage
Y1  - 2022
U6  - https://doi.org/10.3390/bioengineering9100528
SN  - 2306-5354
N1  - Der Artikel gehört zum Sonderheft "Computational Biomechanics"
VL  - 9
IS  - 10, Early Access
SP  - 1
EP  - 17
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Miyamoto, Ko-Ichiro
A1  - Sato, Takuya
A1  - Abe, Minami
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Light-addressable potentiometric sensor as a sensing element in plug-based microfluidic devices
JF  - Micromachines
N2  - A plug-based microfluidic system based on the principle of the light-addressable potentiometric sensor (LAPS) is proposed. The LAPS is a semiconductor-based chemical sensor, which has a free addressability of the measurement point on the sensing surface. By combining a microfluidic device and LAPS, ion sensing can be performed anywhere inside the microfluidic channel. In this study, the sample solution to be measured was introduced into the channel in a form of a plug with a volume in the range of microliters. Taking advantage of the light-addressability, the position of the plug could be monitored and pneumatically controlled. With the developed system, the pH value of a plug with a volume down to 400 nL could be measured. As an example of plug-based operation, two plugs were merged in the channel, and the pH change was detected by differential measurement.
KW  - light-addressable potentiometric sensor
KW  - plug-based microfluidic device
KW  - chemical sensor
Y1  - 2016
U6  - https://doi.org/10.3390/mi7070111
SN  - 2072-666X
N1  - This article belongs to the Special Issue "Micro/Nano Devices for Chemical Analysis"
VL  - 7
IS  - 7
SP  - 111
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Jildeh, Zaid B.
A1  - Oberländer, Jan
A1  - Kirchner, Patrick
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
T1  - Thermocatalytic Behavior of Manganese (IV) Oxide as Nanoporous Material on the Dissociation of a Gas Mixture Containing Hydrogen Peroxide
JF  - Nanomaterials
N2  - In this article, we present an overview on the thermocatalytic reaction of hydrogen peroxide (H₂O₂) gas on a manganese (IV) oxide (MnO₂) catalytic structure. The principle of operation and manufacturing techniques are introduced for a calorimetric H₂O₂ gas sensor based on porous MnO₂. Results from surface analyses by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) of the catalytic material provide indication of the H₂O₂ dissociation reaction schemes. The correlation between theory and the experiments is documented in numerical models of the catalytic reaction. The aim of the numerical models is to provide further information on the reaction kinetics and performance enhancement of the porous MnO₂ catalyst.
Y1  - 2018
U6  - https://doi.org/10.3390/nano8040262
SN  - 2079-4991
VL  - 8
IS  - 4
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Pilas, Johanna
A1  - Yazici, Y.
A1  - Selmer, Thorsten
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Application of a portable multi-analyte biosensor for organic acid determination in silage
JF  - Sensors
N2  - Multi-analyte biosensors may offer the opportunity to perform cost-effective and rapid analysis with reduced sample volume, as compared to electrochemical biosensing of each analyte individually. This work describes the development of an enzyme-based biosensor system for multi-parametric determination of four different organic acids. The biosensor array comprises five working electrodes for simultaneous sensing of ethanol, formate, d-lactate, and l-lactate, and an integrated counter electrode. Storage stability of the biosensor was evaluated under different conditions (stored at +4 °C in buffer solution and dry at −21 °C, +4 °C, and room temperature) over a period of 140 days. After repeated and regular application, the individual sensing electrodes exhibited the best stability when stored at −21 °C. Furthermore, measurements in silage samples (maize and sugarcane silage) were conducted with the portable biosensor system. Comparison with a conventional photometric technique demonstrated successful employment for rapid monitoring of complex media.
Y1  - 2018
U6  - https://doi.org/10.3390/s18051470
SN  - 1424-8220
VL  - 18
IS  - 5
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Wagner, Torsten
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - A LAPS-based differential sensor for parallelized metabolism monitoring of various bacteria
JF  - Sensors
N2  - Monitoring the cellular metabolism of bacteria in (bio)fermentation processes is crucial to control and steer them, and to prevent undesired disturbances linked to metabolically inactive microorganisms. In this context, cell-based biosensors can play an important role to improve the quality and increase the yield of such processes. This work describes the simultaneous analysis of the metabolic behavior of three different types of bacteria by means of a differential light-addressable potentiometric sensor (LAPS) set-up. The study includes Lactobacillus brevis, Corynebacterium glutamicum, and Escherichia coli, which are often applied in fermentation processes in bioreactors. Differential measurements were carried out to compensate undesirable influences such as sensor signal drift, and pH value variation during the measurements. Furthermore, calibration curves of the cellular metabolism were established as a function of the glucose concentration or cell number variation with all three model microorganisms. In this context, simultaneous (bio)sensing with the multi-organism LAPS-based set-up can open new possibilities for a cost-effective, rapid detection of the extracellular acidification of bacteria on a single sensor chip. It can be applied to evaluate the metabolic response of bacteria populations in a (bio)fermentation process, for instance, in the biogas fermentation process.
Y1  - 2019
U6  - https://doi.org/10.3390/s19214692
SN  - 1424-8220
VL  - 19
IS  - 21
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Kopp, Alexander
A1  - Schunck, Laura
A1  - Gosau, Martin
A1  - Smeets, Ralf
A1  - Burg, Simon
A1  - Fuest, Sandra
A1  - Kröger, Nadja
A1  - Zinser, Max
A1  - Krohn, Sebastian
A1  - Behbahani, Mehdi
A1  - Köpf, Marius
A1  - Lauts, Lisa
A1  - Rutkowski, Rico
T1  - Influence of the casting concentration on the mechanical and optical properties of Fa/CaCl2-derived silk fibroin membranes
JF  - International Journal of Molecular Sciences
N2  - In this study, we describe the manufacturing and characterization of silk fibroin membranes derived from the silkworm Bombyx mori. To date, the dissolution process used in this study has only been researched to a limited extent, although it entails various potential advantages, such as reduced expenses and the absence of toxic chemicals in comparison to other conventional techniques. Therefore, the aim of this study was to determine the influence of different fibroin concentrations on the process output and resulting membrane properties. Casted membranes were thus characterized with regard to their mechanical, structural and optical assets via tensile testing, SEM, light microscopy and spectrophotometry. Cytotoxicity was evaluated using BrdU, XTT, and LDH assays, followed by live–dead staining. The formic acid (FA) dissolution method was proven to be suitable for the manufacturing of transparent and mechanically stable membranes. The fibroin concentration affects both thickness and transparency of the membranes. The membranes did not exhibit any signs of cytotoxicity. When compared to other current scientific and technical benchmarks, the manufactured membranes displayed promising potential for various biomedical applications. Further research is nevertheless necessary to improve reproducible manufacturing, including a more uniform thickness, less impurity and physiological pH within the membranes.
Y1  - 2020
U6  - https://doi.org/10.3390/ijms21186704
SN  - 1422-0067
N1  - Special issue: Optimization of Biomaterials for Reconstructive and Regenerative Medicine
VL  - 21
IS  - 18 art. no. 6704
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Molinnus, Denise
A1  - Beging, Stefan
A1  - Lowis, Carsten
A1  - Schöning, Michael Josef
T1  - Towards a multi-enzyme capacitive field-effect biosensor by comparative study of drop-coating and nano-spotting technique
JF  - Sensors
N2  - Multi-enzyme immobilization onto a capacitive field-effect biosensor by nano-spotting technique is presented. The nano-spotting technique allows to immobilize different enzymes simultaneously on the sensor surface with high spatial resolution without additional photolithographical patterning. The amount of applied enzymatic cocktail on the sensor surface can be tailored. Capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensors with Ta2O5 as pH-sensitive transducer layer have been chosen to immobilize the three different (pL droplets) enzymes penicillinase, urease, and glucose oxidase. Nano-spotting immobilization is compared to conventional drop-coating method by defining different geometrical layouts on the sensor surface (fully, half-, and quarter-spotted). The drop diameter is varying between 84 µm and 102 µm, depending on the number of applied drops (1 to 4) per spot. For multi-analyte detection, penicillinase and urease are simultaneously nano-spotted on the EIS sensor. Sensor characterization was performed by C/V (capacitance/voltage) and ConCap (constant capacitance) measurements. Average penicillin, glucose, and urea sensitivities for the spotted enzymes were 81.7 mV/dec, 40.5 mV/dec, and 68.9 mV/dec, respectively.
Y1  - 2020
SN  - 1424-8220
U6  - https://doi.org/10.3390/s20174924
N1  - Special issue: Multisensor Systems and Signal Processing in Analytical Chemistry
VL  - 20
IS  - 17
PB  - MDPI
CY  - Basel
ER  - 
TY  - BOOK
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
ED  - Yoshinobu, Tatsuo
ED  - Schöning, Michael Josef
T1  - Light-addressing and chemical imaging technologies for electrochemical sensing
Y1  - 2020
SN  - 978-3-03943-029-1
U6  - https://doi.org/10.3390/books978-3-03943-029-1
N1  - This book is a printed edition of the Special Issue Light-Addressing and Chemical Imaging Technologies for Electrochemical Sensing that was published in Sensors
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Pellegrini, Paul A.
A1  - Howell, Nicholas R.
A1  - Shepherd, Rachael K.
A1  - Lengkeek, Nigel A.
A1  - Paulßen, Elisabeth
A1  - Katsifis, Andrew G.
A1  - Greguric, Ivan
T1  - Synthesis and Radiolabelling of DOTA-Linked Glutamine Analogues with 67,68Ga as Markers for Increased Glutamine Metabolism in Tumour Cells
JF  - Molecules
Y1  - 2013
U6  - https://doi.org/10.3390/molecules18067160
SN  - 1420-3049
VL  - 18
IS  - 6
SP  - 7160
EP  - 7178
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Valero, Daniel
A1  - Viti, Nicolo
A1  - Gualtieri, Carlo
T1  - Numerical Simulation of Hydraulic Jumps. Part 1: Experimental Data for Modelling Performance Assessment
JF  - Water
Y1  - 2019
U6  - https://doi.org/10.3390/w11010036
SN  - 2073-4441
VL  - 11
IS  - 1
SP  - Art. Nr. 36
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Welden, Rene
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick H.
A1  - Wagner, Torsten
T1  - Light-Addressable Electrodes for Dynamic and Flexible Addressing of Biological Systems and Electrochemical Reactions
JF  - Sensors
N2  - In this review article, we are going to present an overview on possible applications of light-addressable electrodes (LAE) as actuator/manipulation devices besides classical electrode structures. For LAEs, the electrode material consists of a semiconductor. Illumination with a light source with the appropiate wavelength leads to the generation of electron-hole pairs which can be utilized for further photoelectrochemical reaction. Due to recent progress in light-projection technologies, highly dynamic and flexible illumination patterns can be generated, opening new possibilities for light-addressable electrodes. A short introduction on semiconductor–electrolyte interfaces with light stimulation is given together with electrode-design approaches. Towards applications, the stimulation of cells with different electrode materials and fabrication designs is explained, followed by analyte-manipulation strategies and spatially resolved photoelectrochemical deposition of different material types.
Y1  - 2020
U6  - https://doi.org/10.3390/s20061680
SN  - 1424-8220
VL  - 20
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Cosma, Cosmin
A1  - Kessler, Julia
A1  - Gebhardt, Andreas
A1  - Campbell, Ian
A1  - Balc, Nicolae
T1  - Improving the Mechanical Strength of Dental Applications and Lattice Structures SLM Processed
JF  - Materials
N2  - To manufacture custom medical parts or scaffolds with reduced defects and high mechanical characteristics, new research on optimizing the selective laser melting (SLM) parameters are needed. In this work, a biocompatible powder, 316L stainless steel, is characterized to understand the particle size, distribution, shape and flowability. Examination revealed that the 316L particles are smooth, nearly spherical, their mean diameter is 39.09 μm and just 10% of them hold a diameter less than 21.18 μm. SLM parameters under consideration include laser power up to 200 W, 250–1500 mm/s scanning speed, 80 μm hatch spacing, 35 μm layer thickness and a preheated platform. The effect of these on processability is evaluated. More than 100 samples are SLM-manufactured with different process parameters. The tensile results show that is possible to raise the ultimate tensile strength up to 840 MPa, adapting the SLM parameters for a stable processability, avoiding the technological defects caused by residual stress. Correlating with other recent studies on SLM technology, the tensile strength is 20% improved. To validate the SLM parameters and conditions established, complex bioengineering applications such as dental bridges and macro-porous grafts are SLM-processed, demonstrating the potential to manufacture medical products with increased mechanical resistance made of 316L.
Y1  - 2020
U6  - https://doi.org/10.3390/ma13040905
SN  - 1996-1944
VL  - 13
IS  - 4
SP  - 1
EP  - 18
PB  - MDPI
CY  - Basel
ER  -