45 research outputs found
Latest Advances in the Generation of Single Photons in Silicon Carbide
No full textThe major barrier for optical quantum information technologies is the absence of reliable single photons sources providing non-classical light states on demand which can be easily and reliably integrated with standard processing protocols for quantum device fabrication. New methods of generation at room temperature of single photons are therefore needed. Heralded single photon sources are presently being sought based on different methods built on different materials. Silicon Carbide (SiC) has the potentials to serve as the preferred material for quantum applications. Here, we review the latest advances in single photon generation at room temperatures based on SiC
Nano-Magnetic Resonance Imaging (Nano-MRI) Gives Personalized Medicine a New Perspective
No full textThis paper reviews some of the major and most recent advances in nanoscale-magnetic resonance imaging (nano-MRI) for personalized medicine (PM). Nano-MRI may drastically expand the capabilities of the traditional magnetic resonance images (MRI), down to the nanometer scale and possibly, in the near future, at the atomic scale. Nano-MRI is potentially able to observe structures which cannot be seen using today's molecular imaging, with sensitivities of many billions of times better than MRI as currently used in hospitals, for example. The paper briefly reports on the foremost research themes in nano-MRI
Advances in Diamond Nanofabrication for Ultrasensitive Devices
No full textThis paper reviews some of the major recent advances in single-crystal diamond nanofabrication and its impact in nano- and micromechanical, nanophotonics and optomechanical components. These constituents of integrated devices incorporating specific dopants in the material provide the capacity to enhance the sensitivity in detecting mass and forces as well as magnetic field down to quantum mechanical limits and will lead pioneering innovations in ultrasensitive sensing and precision measurements in the realm of the medical sciences, quantum sciences and related technologies
Chlorination disadvantages and alternative routes for biofouling control in reverse osmosis desalination
No full textWith an ever-increasing human population, access to clean water for human use is a growing concern across the world. Seawater desalination to produce usable water is essential to meet future clean water demand. Desalination processes, such as reverse osmosis and multi-stage flash have been implemented worldwide. Reverse osmosis is the most effective technology, which uses a semipermeable membrane to produce clean water under an applied pressure. However, membrane biofouling is the main issue faced by such plants, which requires continuous cleaning or regular replacement of the membranes. Chlorination is the most commonly used disinfection process to pretreat the water to reduce biofouling. Although chlorination is widely used, it has several disadvantages, such as formation of disinfection by-products and being ineffective against some types of microbes. This review aims to discuss the adverse effect of chlorination on reverse osmosis membranes and to identify other possible alternatives of chlorination to reduce biofouling of the membranes. Reverse osmosis membrane degradation and mitigation of chlorines effects, along with newly emerging disinfection technologies, are discussed, providing insight to both academic institutions and industries for the design of improved reverse osmosis systems
F1 style MGU-H applied to the turbocharger of a gasoline hybrid electric passenger car
No full textAbstractWe consider a turbocharged gasoline direct injection (DI) engine featuring a motor-generator-unit (MGU-H) fitted on the turbocharger shaft. The MGU-H receives or delivers energy to the same energy storage (ES) of the hybrid power unit that comprises a motor-generator unit on the driveline (MGU-K) in addition to the internal combustion engine (ICE). The energy supply from the ES is mostly needed during sharp accelerations to avoid turbo-lag, and to boost torque at low speeds. At low speeds, it also improves the ratio of engine crankshaft power to fuel flow power, as well as the ratio of engine crankshaft plus turbocharger shaft power to fuel flow power. The energy supply to the ES is possible at high speeds and loads, where otherwise the turbine could have been waste gated, and during decelerations. This improves the ratio of engine crankshaft plus turbocharger shaft power to fuel flow power.</jats:p
Appassionato: An integrated induction cooktop design
No full textThe way people are cooking is shifting. Were people have had gas hobs for a long time it is now changing to cooking on induction. Cooking on gas will be banned from 2050 on and is disappearing already. The way induction hobs are implemented at the moment is with a glass plate on top while still taking up space on the countertop like with a gas hob. Boretti thought of a solution to use another kind of ceramics able to have the looks of all kinds of materials like marble or nature stone. The concept provided by Boretti at the starting point of this graduation project was a standalone oven with this induction hob solution on top. The assignment was to create a version totally integrated into the countertop since the whole countertop can be made of the same ceramics. To make a design that fits the needs of possible user groups, fit with the trends at the moment and in the future and suit the ways of living from 2021 on, an analysis was performed. Main conclusions were the shift in the marketing Boretti has to make., the change of the way people are living, house are becoming more open, smaller houses in cities are getting more expensive and multifunctionality of space with also making more connection between living room and kitchen are trends to take into account. This results in design changes in kitchen blocks, the need for better air circulation and purifying and multifunctionality in countertop space. The analysis was followed by an ideation phase in which partial problems were tackled with different solutions. The topics ideated on were the user interface, multifunctionality cooking zone indications and the integration possibilities of a combined air extractor and air purifier. This ideation resulted in three different concepts were combinations of partial solutions were made. After making three different concepts, two were combined. The new combined concept has an accessory bar that breaks up the countertop surface into a living part and a cooking part. This accessory bar has space for a range of simple accessories to things like a Boretti water tap. Personalisable Qi charging spots can be chosen while the consumer configures the countertop. To make sure the surface above the cooking zones can be used totally for other purposes, the control interface is not fixed. This interface is a smart rotational knob with which all cooking zones can be controlled. The final concept is a kitchen island version is worked out in detail. The control knob has a light ring which refers to a gas burner and has haptic and visual feedback for the intensity of the selected zone. The main USPs are the multifunctionality and styling made possible with the material, an improved orientation during cooking and the smart knob. Since there will be differences in the needs and configurations consumers will want to have for this concept. A range of product is suggested to Boretti around this concept.Integrated Product Desig
Comparison of Regenerative Braking Efficiencies of MY2012 and MY2013 Nissan Leaf
No full textThe use of kinetic energy recovery systems (KERS) is the best solution presently available to dramatically improve the energy economy of passenger cars. The paper presents an experimental analysis of the energy flow to and from the battery of a MY 2012 and a MY 2013 Nissan Leaf covering the Urban Dynamometer Driving Schedule (UDDS). The two vehicles differ for the integration of the electric drivetrain component, plus a different use of the electric motor and the regenerative brakes, in addition to a different weight. It is shown that while the efficiency propulsive power to vehicle / power from battery are basically unchanged, at about 87-89 %, the efficiency power to the battery / braking power to vehicle are significantly improved from values of about 70-80 % to values of 72-87 %. The analysis provides a state-of-the-art benchmark of the propulsion and regenerative braking efficiencies of electric vehicles
Design of Direct Injection Jet Ignition High Performance Naturally Aspirated Motorcycle Engines
No full textThanks to the adoption of high pressure, direct injection and jet ignition, plus electrically assisted turbo-compounding, the fuel conversion efficiency of Fédération Internationale de l’Automobile (FIA) F1 engines has been spectacularly improved up to values above 46% peak power, and 50% peak efficiency, by running lean of stoichiometry stratified in a high boost, high compression ratio environment. Opposite, Federation Internationale de Motocyclisme (FIM) Moto-GP engines are still naturally aspirated, port injected, spark ignited, working with homogeneous mixtures. This old fashioned but highly optimized design is responsible for relatively low fuel conversion efficiencies, and yet delivers an outstanding specific power density of 200 kW/liter. The potential to improve the fuel conversion efficiency of Moto-GP engines through the adoption of direct injection and jet ignition, prevented by the current rules, is herein discussed based on simulations. As two-stroke engines may benefit from direct injection and jet ignition more than four-stroke engines, the opportunity of a return of two-stroke engines is also argued, similarly based on simulations. About the same power, but at a better fuel efficiency, of today’s 1000 cm3 four stroke engines, may be obtained with lean stratified direct injection jet ignition engines, four-stroke of 1450 cm3, or two-stroke of 1050 cm3. About the same power and fuel efficiency may also be delivered with stoichiometric engines direct injection jet ignition two-stroke of 750 cm3
Numerical study of the substitutional diesel fuel energy in a dual fuel diesel-LPG engine with two direct injectors per cylinder
No full textHalf/Full Toroidal, Single/Double Roller, CVT Based Transmission for a Super-Turbo-Charger
No full textTurbocharging dramatically improves the power density of internal combustion engines. However, when the energy to turbine is either smaller or larger than what is needed by the compressor for a specific steady state or transient point, there are downfalls, such as turbo-lag, lack of boost, or wasted exhaust energy. Here we propose a super-turbo-charger, where the turbo-charger shaft is connected to the crankshaft through a continuously variable transmission (CVT) and gears’ pairs. Different designs are considered, half-toroidal and full-toroidal, single-roller or double-roller, single-CVT or two-CVT-in-series. Energy is drawn from the crankshaft or delivered to the crank-shaft to improve the steady or transient operation. In this paper, a six-cylinder, dual fuel diesel injection ignition engine is super-turbocharged. Engine performance simulations show the opportunity to achieve a nearly flat maximum torque all over the range of engine speeds and very high efficiencies from one fourth of the load up-wards
