Development of a compact, self-stabilizing handheld camera mount
My purpose of the Research was build a small, compact device for the GoPro, which minimizes shocks that are typically caused by running and makes the video stable. The device must fit into a backpack and must be designed for the GoPro. This scenario raised two central questions for me: Which laws of physics are used for the stabilization of the camera? How can those laws of physics constructively be transformed into a working device? I have built four prototypes. To know which prototype was the best, I compared them and gained data into diagrams. The result with the last prototype was very impressive and encouraging, whether your are walking, running or skiing, the videos were no longer shaky. My final prototype consisted of a hollow tube which extended vertically. My conclusions: First the handheld camera mount mustn't be too light, as the inertia of the device is too low. Second it mustn't be too heavy, because you normally have to hold it over a certain time interval. Inertia as well as lever principal were essential to produce a smooth video. The most difficult part to build was the fully gimbaled suspension because it requires as little friction as possible and it must be precise and solid.
Fabrication of Hydrophobic Coatings Using the Sol-Gel Method
The aim of our research is to produce superhydrophobic coatings on both glass and cloth substrates in order to achieve high contact angles and low sliding angles for self-cleaning. In addition, we aim to modify these coatings to be as transparent as possible so as not to interfere with the aesthetics of the objects which will be coated. To achieve this goal, we synthesised a solution using 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (a type of FAS), silica nanoparticles (SiO2), tetraethyl orthosilicate (TEOS), (3-glycidyloxypropyl) trimethoxysilane (Glymo) and deionised water. Using the convenient sol-gel method, coatings of 20% and 30% by weight of FAS-SiO2 nanoparticles were prepared on glass and cotton substrates. It was found that coatings containing 30% by weight of FAS-modified SiO2 nanoparticles on glass slide produced coatings with water contact angle as high as 162.8° and sliding angle as low as 4°. It can also be seen that for glass substrates, the hydrophobicity increased with an increase in percentage of FAS-modified SiO2 nanoparticles. Although the highest percentage transmittance was about 30%, texts and pictures beneath the coated glass slides were clearly readable. The cotton substrates also exhibited excellent hydrophobicity, with a water contact angle of 150° and sliding angle of 22°. Furthermore, the substrates showed good retention of colour and durability after simulated washing and 72 hours of ultraviolet (UV) weathering chamber test. These results show that the effects of washing and UV on the important properties of the cloth were insignificant.
First photochromic diarylethenes with cyclohexenone ethene "bridge"
Photochromism is determined as reversible transformation between two chemical species, induced by action of light [1]. Herewith, initial form and photoinduced isomer have different properties, first of all, spectral. The phenomenon is attractive for the design of hi-tech materials for different applications, including optical memory elements and molecular switches. Diarylethenes are the most promising class of organic photochromic compounds due to outstanding thermal stability of both isomers and high photostability [2, 3]. Photochromism of diarylethenes explained by reversible electrocyclic reaction of hexatriene system, provoked by UV light, back reaction is induced by visible light. In this work we have proposed a new class of photochromic diarylethenes with cyclohexenone ethene “bridge” 4. The key stage of the synthesis is “one-pot” reaction of ketoesters 1 and chalkones 2 in ethanol in the presence of sodium ethoxide that includes Michael reaction and subsequent intramolecular condensation of the resulting product. The final decarboxylation of semi-product 3 results in target diarylethenes 4. We have prepared a wide range of photochromic diarylethenes with thiophene, oxazole, imidazole and benzene derivatives as aryl moieties. The spectral characteristics of compounds obtained have also been discussed.
Antimicrobial and Heavy Metal Sequestration Capacities of Graphene Polymer Nanofilms
Membrane bioreactors (MBR) are important components in the production of effluent in wastewater treatment systems. However, MBR are susceptible to biofouling, a process by which bacteria colonize the surface of the membrane in contact with water. Graphene could be a solution to biofilm formation. In this study, the graphene polymer nanocomposite’s antimicrobial and heavy metal removal properties and the mechanisms behind the properties were investigated. Five different films of nanocomposites with a form of graphene and a polymer were synthesized: Graphene, Graphene Oxide, PVK-GO, PVK-G, PVK. A Büchner funnel and a vacuum pump were used to coat membrane filters with solutions of each nanomaterial. Using the Büchner funnel, E. coli and B. subtilis bacteria were filtered through the filter and both the filtrate and the filter were examined for bacterial content. Similarly, a Pb2+ solution was filtered through the coated filters and percentage removal of the ion was calculated using Atomic Absorbtion Spectrometry. Further analysis from SEM data, ATR-IR, and an Oxidative Stress test revealed that the PVK-GO nanocomposite inactivates bacteria by causing oxidative stress and the carboxyl group binds to lead ions. PVK-GO was most effective at removing the highest percentage of heavy metal and inactivated the most bacteria and displayed the most antimicrobial properties. PVK-GO coatings provide an efficient and economical alternative to the current wastewater industry standard and can save millions of dollars and reduce environmental waste. Also, the coatings have applications in indwelling medical devices and can reduce the risks associated with biofilm formational and bacterial infections.