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Introduktion: Tredimensionell printing (3DP) är en teknik som använder en digital fil för att producera ett 3D-objekt, exempelvis en läkemedelstablett, genom en så kallad additiv process, vilket innebär att byggmaterialet läggs på successivt lager för lager. Syfte: Denna studie har ett tvådelat syfte, dels att presentera två 3D-printingstekniker, laserbaserade system (SLA) och smält deponeringsmodellering (FDM) som idag används för läkemedelsframställning samt göra en metodjämförelse, dels att ge exempel på samt beskriva några olika tabletter som framställts med hjälp av dessa tekniker. Metod: Studien genomfördes i form av en systematisk litteraturstudie och använde i första hand databasen PubMed för att hitta relevanta vetenskapliga artiklar i ämnet. Resultat: Resultatet redovisas i två delar. Första delen jämför de två viktiga 3DP-tekniker laserbaserade system (SLA) och smält deponeringsmodellering (FDM). Andra delen beskriver olika typer av tabletter som kan framställas med 3D-printing. Slutsats: Utifrån resultatet framgår det att 3D-printing är en framväxande teknik som skapar nya, intressanta terapimöjligheter. Dessutom framgår det att FDM lämpar sig bättre än SLA som framställningsteknik inom läkemedelsvärlden där det ställs höga krav på kostnadseffektivitet men också på grund av dess förmåga att generera formuleringar med olika frisättningsprofiler och på så sätt producera individanpassade läkemedel.

This project involves the design and development of a cell stretching bioreactor device that can work in conjunction with a Random Positioning Machine (RPM) apparatus. Microgravity environments, such as in space, have been shown to induce alterations in cellular development due to inadequate mechanical loading of biological tissue. Because of this, long-term spaceflight has led to many health concerns, including osteoporosis and muscle atrophy. Space travel is rare and costly, making this research difficult to conduct, however; techniques to simulate microgravity on Earth can be achieved by using a Random Positioning Machine. This device has been a beneficial tool used to study the effect gravity has on cellular growth, yet certain tissues in the body, such as bone and muscle, require mechanical stress, strain, and mechanical loading to develop properly. Because of this, a device that can induce strain on cells while subjected to microgravity conditions is needed to further improve cellular research for space exploration. The constructed bioreactor consists of 3D printed and custom-made components that can induce uniaxial cyclic strain on cells adhered to an elastic membrane. Validation and testing of the device have shown that this bioreactor is suitable for cellular experimentation to work in conjunction with an RPM to deliver a controlled amount of strain while under microgravity conditions. / Bioengineering

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Ionizing radiation is often used within medicine for diagnosis and treatments. Because ionizingradiation can be harmful to the body, it is important to know how it affects the tissue. Dosimetryis the study of how ionizing radiation deposits energy in a material. To measure how much ionizingradiation is deposited in the body, gas-filled detectors are often used. An ionization chamber isa type of gas-filled detector and exists in different shapes and sizes, depending on what kind ofmeasurements it is made for. Because ionization chambers are relatively expensive, it is often notpossible to buy one for each type of measurement that is to be done. This results in ionizationchambers being used for measurements they are not optimized for. This report evaluates thepossibility of 3D printing ionization chambers to make it easier to optimize them for specificmeasurements. The process included creating models of ionization chambers using CAD-software,slicing them and then 3D printing them. The 3D printed models were then brought to the SwedishRadiation Safety Authority for measurements. The ionization chambers were connected to highvoltage, and exposed to ionizing radiation in the form of high-intensity gamma-ray fields. Theoutput current of the ionization chamber was measured, which is proportional to the field intensity.The results were similar to those of a commercial ionization chamber. The conclusion is that it ispossible to 3D print ionization chambers. However, to get more accurate results, the design has tobe further optimized and more measurements need to be done.

In this thesis, support structures of a polymer powder based process called XXXXXXXX™ are examined. These structures are crucial for most additive manufacturing processes. The effects of several factors on five industrially important characteristics of support structures are examined by use of the Design of Experiment (DoE) method. It describes the planning as well as the analysis of the experiments. The experiments are planned in a fractional factorial 211-5 design with 64 specimens, resulting in a resolution of IV. The analysis of the data is done by use of the ANOVA method, with which the significance of effects and interaction effects are checked. / I detta examensarbete undersöks stödstrukturer för en polymer-pulverbaserad process kallad XXXXXXXX. Dessa strukturer är väsentliga för de flesta aditiv tillverkning. Med hjälp av metoden "Design of Experiment" (DoE) undersöks effekten av flera faktorer på fem industriellt viktiga egenskaper för stödstrukturer. DoE beskriver både planeringen och analysen av experiment. Experimenten planeras i en fraktionerad faktoriell 211-5 design med 64 provexemplar vilket resulterar i en upplösning av IV. Dataanalysen genomförs med hjälp av ANOVA-metoden, med vilken signifikansen av effekter och interaktionseffekter kan undersökas.

This design thesis is an assessment of the tectonic capabilities and applications of large format 3D printing, given the current available and practiced technologies. This review consists of an analysis of the technical specifications and limitations of the various forms and methods of 3D printing at all scales, followed by an in-depth analysis of technologies that have been adopted and employed at an architectural scale. A number of case studies are assessed to create a typology of tectonic types created by employing 3D printing technologies. These tectonic types: Holistic/Homogenous, Complementary/Integrative, Structural, and Sculptural are then tested to see how they can be incorporated into the design process. This study culminates in a design project that utilizes these technologies and tectonic types in a higher educational facility focused on fabrication and continued research into 3D printed construction. The design acts as a prototypical model for the implementation of 3D printed technologies into the design and construction process, specifically focused on educational institutions on existing campuses. Advancements in this technology and strategies of application have yielded enough capabilities for this design assessment to be formed.

The ongoing energy and environmental crises have pushed the transportation sector, a major greenhouse gas emitter, to seek sustainable fuel and technology alternatives. Natural gas and bio-methane are potential alternatives with numerous advantages over conventional fuels. Adsorbed natural gas (ANG) technology uses porous adsorbent material to store methane efficiently at lower pressures. An issue limiting this technology is the lack of compact tanks with efficient adsorbent packing that increase storage capacity. This study addresses the need for more compact ANG tanks by creating novel binder-less monolithic activated carbon monolith adsorbents with targeted porosity. A template is produced using 3D printing and a commercially available phenolic resin as a filling material. Upon thermal treatment, the 3D-printed template combusts with molecular oxygen in its structure, and the resin is transformed into activated carbon by pyrolysis. Longer activation times led to higher BET surface areas. However, after activation periods beyond 15 minutes, the surface area increase is obtained at the expense of a higher burn-off, which affects the material density. Adsorption of 0.04g/g of methane was measured at 30 bar and 298 K on the activated carbon monolith with the highest BET surface area (516 m2/g). Results in the same conditions on a super high surface area Maxsorb activated carbon were 0.13g/g. Although the methane capacity obtained is lower than in a commercial sample, it was demonstrated that producing an activated carbon monolith with tailored porosity is possible. New techniques for activation should be studied to enhance their gravimetric capacity to make ANG competitive.

This work aims to implement 3D microstructures that generate light with orbital angular momentum towards applications in Biophotonics. Over the past few decades, 3D printing has established itself as the most versatile technology with effortless adaptability. Parallel to this, the concept of miniaturiza tion has seen tremendous growth irrespective of the field and has become an estab lished trend motivated by the need for compact, portable and multi-function devices. Therefore, when these two concepts get together, i.e., 3D printing of miniaturized objects, it could lead to an exciting path with endless opportunities. When it comes to optics, miniaturized 3D printing offers the potential to create compact optical micro-systems and exhibits a way to manufacture freeform µ-optics. In particular, two-photon lithography (TPL) is a cutting edge 3D printing technology that has re cently demonstrated groundbreaking solutions for optics as it offers high resolution with a great degree of flexibility. With a TPL 3D printer, it is possible to fabricate complex µ-optical elements and employ them for compelling applications. In recent years, light with orbital angular momentum (OAM), or ”twisted” light, has captured the interests of several researchers due to its inspiring applications. Tra ditionally, to generate OAM beams, one would require bulk, table-top optics, restrict ing their applications to over-the-table setup. An alternative approach of OAM beam generation is through µ-structures over the fiber, as they can open up new opportu nities, especially in Bioscience, and facilitate in-vivo operations. In particular, this probe-like setup can be used for processes such as optical trapping, high-resolution microscopy, etc. Hence, I propose the development of a novel approach with un precedented capabilities for generating OAM beams right from single-mode optical fibers, by transforming its Gaussian-like output beam by using complex 3D printed microstructures. In this document, I will showcase designs and results on generating Bessel beams (both zeroth- and high-order) and high-NA converging beams (with and without OAM) for optical trapping from the fiber. Remarkably, I achieved the first-ever fiber-based high-order Bessel beam generation and the first-ever fiber optical tweezers with OAM.

Metal Organic Frameworks (MOFs) are a class of porous materials that are predominantly obtained as powders and have been investigated as a solid sorbent for gas separation or carbon capture applications from combustion exhaust gases. The manufacturing of products with MOFs to use them for real life applications is still a major problem. The most common productization method used is to form pellets of the powder MOFs. This has a limitation on the product shape which makes it difficult for it to be used in gas separation applications. This study focuses on using additive manufacturing technique to give MOFs a lattice (mesh-like) geometry which is useful for gas separation applications as the mixture of gases would be able to pass through the lattice structure and be separated due to the inherent MOF properties and characteristics. Two MOFs based on magnesium and manganese salts have been studied in this project. An extrudable paste developed using alginate gel as a binder with these MOFs. With alterations in paste formulations and 3D printer parameters, lattice structures were printed using the two MOFs. CO2 and N2 gas uptakes were measured showing that the structure adsorbs CO2 gas to a higher extend which results in the separation of N2 gas in both materials. When compared to their pristine powder form, other properties of the MOFs such as crystallinity, microstructure, reusability and surface area remain to be preserved after being 3D printed in both cases.