In opdracht van het Groninger Instituut Archeologie van de Rijksuniversiteit Groningen en de Doggerland projectgroep is onderzoek gedaan naar de effectiviteit van de Reflectance Transformation Imaging (RTI) en fotogrammetrie. Deze twee technieken zijn toegepast op kaakfragmenten met gebitselementen uit het Mesolithicum en de Bronstijd om te onderzoeken of het mogelijk is om met deze technieken een verschil in dieet aan te tonen. Daarnaast is de Artec Spider 3D-scanner toegepast op de gebitselementen. Deze scans zijn gemaakt door externen, waarna de resultaten opgenomen zijn in het onderzoek. Uit het onderzoek is gebleken dat het vaststellen van specifieke verschillen van gebitsslijtage tussen jager-verzamelaars en vroege boeren niet mogelijk is op basis van de RTI-techniek en fotogrammetrie. Beide technieken leveren niet de gewenste resultaten. Zo maakt de RTI-techniek enkel een opname van bovenaf, waardoor de zijaanzichten van de gebitselementen niet onderzocht kunnen worden. De fotogrammetrische techniek is niet gedetailleerd genoeg. Zo vloeien verschillende gebitselementen in elkaar over en zijn sommige elementen niet scherp genoeg om met zekerheid vast te stellen of hier überhaupt slijtagesporen op zijn aangetroffen. Desondanks is het wel mogelijk geweest om de slijtagesporen in beeld te brengen met de Artec Spider 3D-scanner. Deze scanner maakt het mogelijk om de specifieke verschijnselen van gebitsslijtage op de gebitselementen uit het Mesolithicum en de Bronstijd in beeld te brengen.
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Currently the advances in the field of 3D printing are causing a revolution in the (bio-)medical field. With applications ranging from patient-specific anatomical models for surgical preparation to prosthetic limbs and even scaffolds for tissue engineering, the possibilities seem endless. Today, the most widely used method is FDM printing. However, there is still a limited range of biodegradable and biocompatible materials available. Moreover, printed implants like for instance cardiovascular stents require higher resolution than is possible to reach with FDM. High resolution is crucial to avoid e.g. bacterial growth and aid to mechanical strength of the implant. For this reason, it would be interesting to consider stereolithography as alternative to FDM for applications in the (bio-) medical field. Stereolithography uses photopolymerizable resins to make high resolution prints. Because the amount of commercially available resins is limited and hardly biocompatible, here we investigate the possibility of using acrylates and vinylesters in an effort to expand the existing arsenal of biocompatible resins. Mechanical properties are tailorable by varying the crosslink density and by varying the spacer length. To facilitate rapid production of high-resolution prints we use masked SLA (mSLA) as an alternative to conventional SLA. mSLA cures an entire layer at a time and therefore uses less time to complete a print than conventional SLA. Additionally, with mSLA it takes the same time to make 10 prints as it would to make only one. Several formulations were prepared and tested for printability and mechanical strength.
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Light scattering is a fundamental property that can be exploited to create essential devices such as particle analysers. The most common particle size analyser relies on measuring the angle-dependent diffracted light from a sample illuminated by a laser beam. Compared to other non-light-based counterparts, such a laser diffraction scheme offers precision, but it does so at the expense of size, complexity and cost. In this paper, we introduce the concept of a new particle size analyser in a collimated beam configuration using a consumer electronic camera and machine learning. The key novelty is a small form factor angular spatial filter that allows for the collection of light scattered by the particles up to predefined discrete angles. The filter is combined with a light-emitting diode and a complementary metal-oxide-semiconductor image sensor array to acquire angularly resolved scattering images. From these images, a machine learning model predicts the volume median diameter of the particles. To validate the proposed device, glass beads with diameters ranging from 13 to 125 µm were measured in suspension at several concentrations. We were able to correct for multiple scattering effects and predict the particle size with mean absolute percentage errors of 5.09% and 2.5% for the cases without and with concentration as an input parameter, respectively. When only spherical particles were analysed, the former error was significantly reduced (0.72%). Given that it is compact (on the order of ten cm) and built with low-cost consumer electronics, the newly designed particle size analyser has significant potential for use outside a standard laboratory, for example, in online and in-line industrial process monitoring.
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Size measurement plays an essential role for micro-/nanoparticle characterization and property evaluation. Due to high costs, complex operation or resolution limit, conventional characterization techniques cannot satisfy the growing demand of routine size measurements in various industry sectors and research departments, e.g., pharmaceuticals, nanomaterials and food industry etc. Together with start-up SeeNano and other partners, we will develop a portable compact device to measure particle size based on particle-impact electrochemical sensing technology. The main task in this project is to extend the measurement range for particles with diameters ranging from 20 nm to 20 um and to validate this technology with realistic samples from various application areas. In this project a new electrode chip will be designed and fabricated. It will result in a workable prototype including new UMEs (ultra-micro electrode), showing that particle sizing can be achieved on a compact portable device with full measuring range. Following experimental testing with calibrated particles, a reliable calibration model will be built up for full range measurement. In a further step, samples from partners or potential customers will be tested on the device to evaluate the application feasibility. The results will be validated by high-resolution and mainstream sizing techniques such as scanning electron microscopy (SEM), dynamic light scattering (DLS) and Coulter counter.
Nano and micro polymeric particles (NMPs) are a point of concern by environmentalists and toxicologist for the past years. Their presence has been detected in many environmental bodies and even in more recently human blood as well. One of the most common paths these particles take to enter living organisms is via water consumption. However, despite the efforts of different academic and other knowledge groups, there is no consensus about standards methods which can be used to qualifying and quantifying these particles, especially the submicrometric ones. Many different techniques have been proposed like field flow fractionation (FFF) followed by multi angle laser scattering (MALS), pyrolysis-GC and scanning electron microscopy (SEM). Additionally, the sampling collection and preparation is also considered a difficult step, as such particles are mostly present in very low concentration. Nanocatcher proposes the use of submerged drones as a sampling collection tool to monitor the presence of submicrometric polymeric particles in water bodies. The sample collections will be done using special membrane systems specially designed for the drone. After collected, the samples will be analysed using FFF+MALS, SEM and Py-GC. If proven successful, the use of submerged drones can strongly facilitate sampling and mapping of submicrometric polymeric particles in water bodies and will provide an extensive and comprehensive map of the presence of these particles in such environment.
Thermo Fisher Scientific is exploring Augmented & Virtual Reality (AR&VR) applications for electron microscopy and corresponding business cases for future projects.Materials and structural analyses impact our everyday life. From the medicines we take, the vaccines we receive, to the cars we drive, Thermo Fisher Scientific’s electron microscopes, software, and services drive scientific breakthroughs that help solve some of the world’s most difficult challenges. The Central Service Department is driving research related to training and service solutions using AR&VR because it recognises the vast benefits these technologies can offer its customers around the globe.Partner: Thermo Fisher Scientific’s Central Service Department
