@inproceedings{HeinrichJacobsDiVonaetal.2022, author = {Heinrich, Moritz and Jacobs, Hannes and Di Vona, Maria Luisa and Pizzoferrato, Roberto and Foitzik, Andreas}, title = {A Test System for Safely Measurements of Cancer-Inducing UV-C Diodes Produced in a Simple and Cost-Effective Way by Rapid Prototyping}, series = {Open Conference Proceedings}, volume = {2}, booktitle = {Open Conference Proceedings}, publisher = {TIB Open Publishing}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-17682}, pages = {197 -- 199}, year = {2022}, abstract = {New technologies leading to better and more efficient light emitting diodes. The emitted radiation reaches higher energy levels and lower wavelengths especially in the UV-C spectrum. UV-C light has a cancer inducing effect on human cells. Therefore it is necessary to work in a safe way with those devices. This work is focused on an open-source solution for rapid 3D printing of an safe UV-C radiation measuring device. Especially for research groups or universities which can not afford big safety labs. After modeling and printing the prototype, a series of tests has shown the functionality of that UV-C Diode test system. By using black printing filaments and infill rates over 50 \%, the transmission of light could be prevented and the system worked well.}, language = {en} } @inproceedings{DoehlerBoehmeHofmannetal.2022, author = {D{\"o}hler, Torsten and B{\"o}hme, Andrea and Hofmann, Mandy and Neumann, Jens and Bochem, Reinhard and Foitzik, Andreas and Geißler, Ute}, title = {Mikrogalvanische Kennzeichnung als Kopierschutz}, series = {Open Conference Proceedings}, volume = {2}, booktitle = {Open Conference Proceedings}, publisher = {TIB Open Publishing}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-17624}, pages = {157 -- 161}, year = {2022}, abstract = {In order to achieve good product quality in electroplating, disturbance variables such as the "dog bone" effect must be avoided. In this work, this approach was used to develop a method for marking as product protection. With a defined structure and optimal parameters, it is possible to deposit unique visually non-differentiable layers on suitable substrates. The deposited layers and their local distribution were characterized by confocal laser microscopy, X-ray fluorescence analysis and laser interference measurements and analyzed qualitatively as well as quantitatively. It thus provides interested parties with an essentially traditional process that can lead to new innovations with the chosen approach.}, language = {de} } @article{BoehmeDoehlerHofmannetal.2023, author = {B{\"o}hme, Andrea and D{\"o}hler, Torsten and Hofmann, Mandy and Neumann, Jens and Bochem, Reinhard and Geißler, Ute and Foitzik, Andreas}, title = {Electrolytical Coating of Inhomogeneous Structures Distributed on Metallic Surfaces}, series = {Materials Science Forum}, volume = {1106}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18825}, pages = {75 -- 80}, year = {2023}, abstract = {In modern electrochemical coating technology, it is common practice to create uniform layers. However, this study focuses on the deposition of non-uniform layers achieved through a deliberate arrangement of micro structured electrodes on the anode side. The "dog bone effect" was employed as the primary approach [1]. When electroplating on an otherwise uniform surface, this effect selectively processes an area influenced by the geometric edge effect (figure 1 left). The coating within this area is intended to be (i) unevenly distributed and (ii) non-reproducible. Process data was obtained through electrochemical simulations and subsequently applied to a specially designed micro-galvanic setup. This enabled the production of suitable micro structured anodes, validation of coating parameters, and the deposition of visually imperceptible structured areas with inhomogeneous properties using "adhesive gold" on appropriate substrates such as silver and nickel. The layers and their local topography were characterized and analyzed using confocal laser microscopy, X-Ray fluorescence analysis (XRF), as well as a self-designed and constructed laser interference device. As a result, this specific galvanic process technology successfully produced metallic layers that (i) cannot be visually confirmed by the naked eye, (ii) exhibit varied microstructural anode geometries, (iii) display unique differences in layer thickness, (iv) possess non-reproducible and chaotic topographies, and (v) can be detected and identified using conventional analysis techniques or a simple interference setup.}, language = {en} } @inproceedings{FriedoHauschultzDoehleretal.2023, author = {Friedo, Maria Helene and Hauschultz, Mike Thomas and D{\"o}hler, Torsten and B{\"o}hme, Andrea and Richetta, Maria and Foitzik, Andreas}, title = {Sustainable production of injection moulds through additive manufacturing and improved application of energy management}, series = {NWK 2023 - Tagungsband zur 23. Nachwuchswissenschaftler*innenkonferenz}, booktitle = {NWK 2023 - Tagungsband zur 23. Nachwuchswissenschaftler*innenkonferenz}, editor = {Stolzenburg, Frieder and Reinboth, Christian and Lohr, Thomas and Vogel, Kathleen}, publisher = {Hochschule Harz}, address = {Wernigerode}, issn = {2627-5708}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18600}, pages = {298 -- 302}, year = {2023}, abstract = {The concept of this thesis is to optimize the manufacturing process of injection moulding tools by using additive manufacturing and thus contribute to environmental protection. For this purpose, the individual steps of the traditional manufacturing process are identified and analysed to determine which steps can be replaced by additive manufacturing. The first step is to clarify which mould components can benefit from additive manufacturing. In particular, the capabilities and limitations of additive manufacturing technologies must be considered. Furthermore, another focus is on how to optimize the cooling and temperature control of the tools. Potential savings through the use of lightweight or insulating surfaces will be examined. In addition to the technical feasibility, the cost-effectiveness of the concept will also be considered. Finally, the contribution of the concept to the reduction of the environmental impact will be evaluated. In particular, energy savings and the reduction of CO2 emissions are taken into account. The potential to optimize the injection mould manufacturing process and reduce environmental impact is significant. Using additive manufacturing can be an economic and environmental advantage.}, language = {en} } @inproceedings{WelzelHauschultzKrumnowetal.2023, author = {Welzel, Felix and Hauschultz, Mike Thomas and Krumnow, Erik and Foitzik, Andreas and Richetta, Maria}, title = {Concept and simulation of micromixers and aliquoting for PCR systems}, series = {NWK 2023 - Tagungsband zur 23. Nachwuchswissenschaftler*innenkonferenz}, booktitle = {NWK 2023 - Tagungsband zur 23. Nachwuchswissenschaftler*innenkonferenz}, editor = {Stolzenburg, Frieder and Reinboth, Christian and Lohr, Thomas and Vogel, Kathleen}, publisher = {Hochschule Harz}, address = {Wernigerode}, issn = {2627-5708}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18611}, pages = {303 -- 306}, year = {2023}, abstract = {In this paper, different concepts for mixing sample and master mix by means of simulation are discussed. The main focus was on mixers with a low dead volume, because of their relevance to PCR. In addition, a concept for aliquoting the mixed solution was elaborated and simulated. The simulation showed very good mixing with serpentineand tesla-mixers at flow rates of 1-16 µL/s. Furthermore, a uniform distribution with aliquoting could be achieved, while a slight dependence between flow rate and pressure was observed. In the further course, these concepts are to be combined and tested on a microfluidic chip. This can then be integrated into the workflow of existing PCR protocols.}, language = {en} } @inproceedings{WelzelHauschultzFriedoetal.2022, author = {Welzel, Felix and Hauschultz, Mike Thomas and Friedo, Maria Helene and Just, Verena and Richetta, Maria and Foitzik, Andreas}, title = {Concept for a Portable Measuring Device for the Quantitative Detection of Legionella}, series = {Open Conference Proceedings}, volume = {2}, booktitle = {Open Conference Proceedings}, publisher = {TIB Open Publishing}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-17616}, pages = {15 -- 17}, year = {2022}, abstract = {According to the drinking water regulation, drinking water systems must be tested for harmful contamination at specified intervals. To meet the legal requirements and save costs and time, a portable analysis method is to be developed. For this purpose, a concept study was conducted. It describes a portable measuring device for the quantitative detection of legionella using real-time PCR. The study includes the construction elements and conditions that are necessary for the collection, processing, and evaluation of the sample. It was found that commercially available PCR systems do not meet the size requirements and can only be represented by an in-house development. In addition, a microfluidic system must be developed that is designed for one-time use and low production cost.}, language = {en} } @inproceedings{StrauchWellmannFriedoetal.2022, author = {Strauch, Jessica and Wellmann, Martin and Friedo, Maria Helene and Welzel, Felix and Foitzik, Andreas}, title = {Miniaturisierung einer Smartwatch f{\"u}r Hautfeuchtesensorik}, series = {Open Conference Proceedings}, volume = {2}, booktitle = {Open Conference Proceedings}, publisher = {TIB Open Publishing}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-17653}, pages = {193 -- 195}, year = {2022}, abstract = {Das Ziel des Projekts ist, den Zustand der Haut von Neurodermitis-Patienten bei verschiedenen Bedingungen und Belastungszust{\"a}nden erfassen zu k{\"o}nnen. Dazu wurde ein Prototyp gefertigt, in den ein Mikrosensor zur Bestimmung der Umgebungsfeuchtigkeit, ein Controller mit Bluetooth zur Daten{\"u}bertragung, sowie ein Lithium-Akku zur Energieversorgung verbaut wurden.}, language = {de} } @inproceedings{HauschultzFriedoDoehleretal.2023, author = {Hauschultz, Mike Thomas and Friedo, Maria Helene and D{\"o}hler, Torsten and B{\"o}hme, Andrea and Richetta, Maria and Foitzik, Andreas}, title = {Additive Manufacturing of Electrodes: Innovative Applications and Opportunities}, series = {NWK 2023 - Tagungsband zur 23. Nachwuchswissenschaftler*innenkonferenz}, booktitle = {NWK 2023 - Tagungsband zur 23. Nachwuchswissenschaftler*innenkonferenz}, editor = {Stolzenburg, Frieder and Reinboth, Christian and Lohr, Thomas and Vogel, Kathleen}, publisher = {Hochschule Harz}, address = {Wernigerode}, issn = {2627-5708}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18621}, pages = {292 -- 297}, year = {2023}, abstract = {Additive manufacturing, also known as 3D printing, has gained tremendous importance in recent years. One of the areas where additive manufacturing is particularly useful is in the fabrication of electrodes. Electrodes are an important component of a wide range of applications, including electrochemistry, biomedical engineering, energy storage, analytics, electronics as well as life sciences. Traditionally, electrodes have been manufactured through costly processes such as etching, electroplating or cutting and milling. Additive manufacturing offers a new way to fabricate electrodes by depositing materials layer by layer (Yap et al., 2015). This opens up new possibilities for designing electrodes with complex geometries and structures that would not be possible using conventional methods. As a result, 3D printed electrodes are gaining interest in fields such as electromobility, water disinfection, manufacturing, and life sciences, which will be presented in this paper.}, language = {en} }