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Montrer texteMontrer source en cacheMontrer URL avec texte source	De ‘Brand Kratten Vuurtoren’ zal bestaan uit 36 lagen kratjes die tot een hoogte komen van 8,64 meter. In totaal worden er 1330 kratjes, 980 gouden en 350 groene, gebruikt. De geschatte bouwtijd is vier tot vijf uur.
Comparer pages textesComparer pages HTMMontrer URL avec texte sourceMontrer URL avec langue cibleDéfinir tudelft.nl comme domaine prioritaire	The ‘Brand Crates Lighthouse’ will comprise 36 crate layers which will reach a height of 8.64 metres. A total of 1,330 crates will be used – 980 golden crates and 350 green crates. The estimated construction time is between four and five hours.

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Montrer texteMontrer source en cacheMontrer URL avec texte source	Veel energie is nodig voor verwarming en klimaatbeheersing van gebouwen. Een efficiënte manier van energieopslag is door in de zomer warmte aan de gebouwen te onttrekken (waardoor ze worden gekoeld) en deze op te slaan in waterhoudende lagen in de grond.
Comparer pages textesComparer pages HTMMontrer URL avec texte sourceMontrer URL avec langue cibleDéfinir tudelft.nl comme domaine prioritaire	Much energy is need to heat and cool buildings. An efficient way to store heat is by extracting it from buildings in the summer (thereby cooling the buildings at the same time) and storing it in layers of water bearing rock underground. In winter the heat can be pumped up again.

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Montrer texteMontrer source en cacheMontrer URL avec texte source	Om de waterhoudende lagen in de regio Delft te bereiken, moet er geboord worden naar een diepte van tussen de anderhalf en twee kilometer. De TU Delft is in gesprek met energiebedrijf Eneco en Energie Beheer Nederland om het aardwarmtesysteem aan te leggen en te exploiteren.
Comparer pages textesComparer pages HTMMontrer URL avec texte sourceMontrer URL avec langue cibleDéfinir tudelft.nl comme domaine prioritaire	In order to reach the water-retaining layers beneath the campus of TU Delft, it is necessary to drill to a depth of between one and a half and two kilometres. TU Delft is in discussions with energy company Eneco and Energie Beheer Nederland concerning the construction and operation of the geothermal system on the campus.

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Op een diepte tussen de 1500 meter en 3000 meter onder de grond heeft water in waterhoudende lagen een temperatuur van circa 55 tot 110 graden Celsius. De warmte uit deze waterhoudende lagen - ook wel aquifers genoemd - kan naar boven worden gehaald om te gebruiken voor het verwarmen van gebouwen.

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At a depth of between 1,500 and 3,000 metres below ground, the water present in water-retaining layers has a temperature of around 55 to 110 degrees Celsius. The heat from these water-retaining layers - also known as aquifers - can be brought to the surface and used to heat buildings. If the temperature is high enough, it can also be used to generate electricity. Geothermal heat is not the same as the temporary storage of heat in groundwater, for example in the summer, so that it can be pumped to the surface for use in winter. This is called heat/cold storage.

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Montrer texteMontrer source en cacheMontrer URL avec texte source	Dik stelt daarom een fundamenteel andere aanpak voor. Hij wil de techniek TeraHertz-spectroscopie gebruiken om grenzen tussen verflagen in kaart te brengen en röntgen-fluorescentie spectroscopie om de distributie van pigmenten in deze lagen te bepalen.
Comparer pages textesComparer pages HTMMontrer URL avec texte sourceMontrer URL avec langue cibleDéfinir tudelft.nl comme domaine prioritaire	Prof. Dik proposes a radically different approach, based on the use of terahertz spectroscopy to map the boundaries between paint layers and X-ray fluorescence spectroscopy to determine the distribution of pigments within these layers.

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Op een diepte tussen de 1500 meter en 3000 meter heeft water in waterhoudende lagen een temperatuur van circa 55 tot 110 graden Celcius. Onder de campus van de TU Delft zit veel water op ideale diepten.

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The temperature of water stored in aquifers at depths of between the 1500 and 3000 metres is approximately 55-110 degrees Celsius. A large volume of water lies at ideal depths beneath the campus at TU Delft. The Delft Geothermal Energy Project (Dutch acronym: DAP) is a collaborative study involving students and researchers who are working on a demonstration project that will use underground water sources to generate geothermal energy in the area surrounding TU Delft.

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Onderzoekers van de afdeling ChemE en het Kavli Instituut van de TU Delft hebben aangetoond dat elektronen zich in lagen van gekoppelde halfgeleider nanodeeltjes vrij kunnen bewegen onder invloed van licht.

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Researchers of the Chemical Engineering department and the Kavli institute of TU Delft have demonstrated that electrons can move freely in layers of linked semiconductor nanoparticles under the influence of light. This new knowledge will be very useful for the development of cheap and efficient quantum dot solar cells. The researchers published their findings on Sunday 25 September on the website of the scientific journal Nature Nanotechnology.

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Dik: ‘Onder het zichtbare oppervlak van de doeken van Oude Meesters gaan verschillende verflagen schuil die inzicht bieden in de maakwijze en restauratiegeschiedenis van schilderijen. Via dit VIDI-project wil ik draagbare, beeldvormende technieken ontwikkelen om deze lagen ruimtelijk en in kleur zichtbaar te maken.’

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The investigations performed by Prof. Joris Dik (36) can be compared with looking over famous artists’ shoulders as they work. He explained, “The various layers of paint present under the visible surface of works by Old Masters allow us to gain an insight into how the paintings were made and their restoration history. The aim of my research project is the development of portable imaging equipment that will make these layers of paint visible in three dimensions and in colour.”

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Montrer texteMontrer source en cacheMontrer URL avec texte source	Onderzoekers van de afdeling ChemE en het Kavli Instituut van de TU Delft hebben aangetoond dat elektronen zich in lagen van gekoppelde halfgeleider nanodeeltjes vrij kunnen bewegen onder invloed van licht.
Comparer pages textesComparer pages HTMMontrer URL avec texte sourceMontrer URL avec langue cibleDéfinir tudelft.nl comme domaine prioritaire	Measures to save energy or generate renewable electricity are mostly taken for houses and office buildings. Regional organisation could nevertheless play a significant role in the optimal use of energy. By using the residual heat produced by local industry to heat new houses, for example. During the National Congress on Energy & Spatial Planning at TU Delft on 22 September, provinces,...

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Op een diepte tussen de 1500 meter en 3000 meter onder de grond heeft water in waterhoudende lagen een temperatuur van circa 55 tot 110 graden Celsius. De warmte uit deze waterhoudende lagen - ook wel aquifers genoemd - kan naar boven worden gehaald om te gebruiken voor het verwarmen van gebouwen.

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At a depth of between 1,500 and 3,000 metres below ground, the water present in water-retaining layers has a temperature of around 55 to 110 degrees Celsius. The heat from these water-retaining layers - also known as aquifers - can be brought to the surface and used to heat buildings. If the temperature is high enough, it can also be used to generate electricity. Geothermal heat is not the same as the temporary storage of heat in groundwater, for example in the summer, so that it can be pumped to the surface for use in winter. This is called heat/cold storage.

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Het CentrAl-concept bestaat uit een centrale laag van vezel metaal laminaten (VML), die worden gesandwiched tussen een of meerdere dikke lagen hoogwaardig aluminium. Zo ontstaat een robuust constructiemateriaal, dat niet alleen bijzonder sterk is, maar daarnaast ook ongevoelig is voor vermoeiing.

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The CentrAl concept comprises a central layer of fibre metal laminate (FML), sandwiched between one or more thick layers of high-quality aluminium. This creates a robust construction material which is not only exceptionally strong, but also insensitive to fatigue. The CentrAl technique allows for simple repairs to be carried out immediately, as is the case in aluminium constructions, – but not the case when using CFRP constructions.

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Montrer texteMontrer source en cacheMontrer URL avec texte source	Promovendus Bouwkunde Ahmed Hisham Hafez wil een baksteen ontwerpen die verschillende functies integreert die nu in verschillende lagen op facades van gebouwen worden aangebracht: isolatie, ventilatie en opslag van warmte.
Comparer pages textesComparer pages HTMMontrer URL avec texte sourceMontrer URL avec langue cibleDéfinir tudelft.nl comme domaine prioritaire	PhD student Architecture Ahmed Hisham Hafez wants to design a brick that has integrated several functions that are now applied to building facades in separate layers: insulation, ventilation and heat storage. The Delft Energy Initiative fund could provide the finances needed to build a brick prototype, develop a system to link the bricks and prepare mass production.

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Het combineren van deze materialen door ze op elkaar te stapelen geeft grenzeloos veel mogelijkheden voor nieuwe elektronische apparaatjes. De meest eenvoudige stapel bestaat uit twee lagen grafeen: bilaag grafeen.

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The research on graphene has paved the way for a new research field on two dimensional layered structures. Graphene is a member of a large family of atomically thin two-dimensional materials. Combining these different materials by stacking them opens virtually limitless possibilities for new electronic devices. The most simple stack is a structure of two layers of graphene: bilayer graphene (BLG). Bilayer graphene is also a two dimensional material and inherits many of the special properties of graphene.

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Daarmee heeft de universiteit het recht om in een gebied van 61 km2 in de gemeenten Delft en Pijnacker-Nootdorp te zoeken naar aardwarmte. Bij aardwarmte – of geothermie – wordt warmte uit waterhoudende lagen in de diepe ondergrond gewonnen voor het verwarmen van gebouwen.

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The Ministry of Economic Affairs has given TU Delft a permit to prospect for geothermal energy. The permit allows the university to explore an area of 61 km2 in the municipalities of Delft and Pijnacker-Nootdorp with the express purpose of locating sources of geothermal energy. The principle behind geothermal energy is that heat is extracted from aquifers deep in the earth’s crust for heating buildings. The temperature in suitable layers can be between 55 and 110 degrees Celsius. TU Delft applied for the permit as part of the Delft Geothermal Project (DAP), an initiative of students and alumni of the Applied Earth Sciences programme. The aim of the programme is to do research into geothermal energy and develop teaching programmes focussing on this subject. In addition, the warm water that is extracted from a depth of over 2000 meters can eventually be used to provide university buildings and dormitories with sustainable heating. The university could potentially save 5 million cubic meters of natural gas per year.

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Zo wissel je bijvoorbeeld vakken als Fysische Instrumentatie en Optics & Microscopy af met een lab course Nanobiology. Dit soort complexe vakken is eenvoudiger onder de knie te krijgen wanneer je samenwerkt; daarom is er in alle lagen van de opleiding veel ruimte voor groepswerk.

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The thorough grounding in physics and mathematics offered by the course, will concentrate on biomedical and nanosciences. The course also includes numerous practical laboratory based lessons, which provide an opportunity to work with advanced research equipment. You’ll be switching between the likes of Physical Instrumentation, Optics & Microscopy and a Nanobiology lab course. Such complex subjects are much easier to master when working with others, therefore the course provide plenty of opportunity for group work. To prepare you, as far as possible, for the international working environment that you’re likely to enter as a result of the study, a significant part of the course will be taught in English. Subjects will be taught in two cities, with subjects such as Biophysics, or Thermodynamics & Transport, covered in Delft and Molecular Biology and Genetics in Rotterdam.

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"Van Gogh gebruikte verschillende pigmentsoorten voor de lagen van zijn schilderijen, maar Rembrandt meestal dezelfde verven. Dat maakt het bij Rembrandt veel lastiger de onderliggende laag te onderscheiden", vertelt Alfeld.

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Joris Dik (TU Delft), Koen Janssens and Matthias Alfeld (both from the University of Antwerp) were involved in the study. They had previously done extensive research into paintings by Van Gogh. "Van Gogh used different types of pigments for the various layers of his paintings, but Rembrandt usually used the same paints. That makes it much more difficult to separate out the underlying layer in Rembrandt", Alfeld explains. The work on the copy showed that the DESY and Brookhaven particle accelerators yielded good results, but so did the mobile scanner. Prof. Joris Dik, who developed the mobile scanning technology, expects that it is his technology that will eventually be used. "The results were promising, and if a mobile scanner is used, the painting does not need to be removed from the museum. That’s a big advantage."

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Hoogleraar Materials for Energy Conversion and Storage, Bernard Dam, heeft met collega’s van de TU Delft en de Vrije Universiteit Amsterdam experimenteel aangetoond dat de interactie tussen de nanodeeltjes en de matrix ervoor kan zorgen dat het waterstofgas sneller vrijkomt. In een modelsysteem bestaande uit dunne lagen Magnesium en Titanium, tonen ze aan dat de druk waarmee het waterstofgas het magnesium verlaat, in dunnere lagen steeds hoger wordt.

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Professor of Materials for Energy Conversion and Storage, Bernard Dam, and his colleagues at TU Delft and VU University Amsterdam have demonstrated experimentally that the interaction between the nanoparticles and the matrix can cause the hydrogen gas to be released faster. Using models consisting of thin layers of magnesium and titanium, they show how the pressure of the hydrogen being released from the magnesium increases as the layers become thinner. This means that it indeed makes sense to store hydrogen in nanoparticles in a matrix. The choice of matrix determines to what extent the hydrogen desorption pressure increases. The researchers published their findings in the October 2011 edition of the scientific journal

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Hoogleraar Materials for Energy Conversion and Storage, Bernard Dam, heeft met collega’s van de TU Delft en de Vrije Universiteit Amsterdam experimenteel aangetoond dat de interactie tussen de nanodeeltjes en de matrix ervoor kan zorgen dat het waterstofgas sneller vrijkomt. In een modelsysteem bestaande uit dunne lagen Magnesium en Titanium, tonen ze aan dat de druk waarmee het waterstofgas het magnesium verlaat, in dunnere lagen steeds hoger wordt.

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Professor of Materials for Energy Conversion and Storage, Bernard Dam, and his colleagues at TU Delft and VU University Amsterdam have demonstrated experimentally that the interaction between the nanoparticles and the matrix can cause the hydrogen gas to be released faster. Using models consisting of thin layers of magnesium and titanium, they show how the pressure of the hydrogen being released from the magnesium increases as the layers become thinner. This means that it indeed makes sense to store hydrogen in nanoparticles in a matrix. The choice of matrix determines to what extent the hydrogen desorption pressure increases. The researchers published their findings in the October 2011 edition of the scientific journal

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Iedereen heeft wel grafeen in huis: grafiet bestaat uit laagjes grafeen en komt bijvoorbeeld voor in potloden, houtskool en roet van kaarsen. In dit onderzoek wordt grafeen gebruikt omdat het de bijzondere eigenschap bezit dat er lagen van één atoom dik van kunnen worden gemaakt.

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Graphene is a unique and very special material, and yet widely available: Everyone has graphene at home: graphite is made of layers of graphene and occurs in for example the carbon of pencils, charcoal, or candle soot. But in this research, graphene is used because of that special property that one can make single-atom-thin monolayers of graphene. Why is such an ultrathin membrane important? Let''s go back to that wire sliding between your fingers. The distance between two bases in DNA is very small, about half a nanometer, which is 100000 times smaller than the width of a human hair! To read off each base along the DNA, one therefore needs a recorder that is smaller than that half nanometer. If your fingers can be scaled down to that size, you are in business. And here’s where these atomically thin graphene membranes are crucial.

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Daar komen immers talloze varianten van flexibele manoeuvreerbare armen voor, bijvoorbeeld bij inktvissen. Hun tentakels zijn opgebouwd uit ingenieuze samenstellingen van spieren die met elkaar samenwerken in verschillende lagen, bundels en pakketjes.

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In the field of keyhole surgery there is a need for long, slender, flexible instruments that can be easily manoeuvred past the internal organs. At present most keyhole surgery is carried out using ‘stiff’ instruments. In his search for more-flexible instruments for keyhole surgery, Dr Breedveld took his inspiration from nature, where there are plenty of examples of flexible and manoeuvrable arms. Take the octopus for example, whose tentacles are made up of an ingenious composition of muscles which work together in various layers, bundles and packages.

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Daarmee heeft de universiteit het recht om in een gebied van 61 km2 in de gemeenten Delft en Pijnacker-Nootdorp te zoeken naar aardwarmte. Bij aardwarmte – of geothermie – wordt warmte uit waterhoudende lagen in de diepe ondergrond gewonnen voor het verwarmen van gebouwen.

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The Ministry of Economic Affairs has given TU Delft a permit to prospect for geothermal energy. The permit allows the university to explore an area of 61 km2 in the municipalities of Delft and Pijnacker-Nootdorp with the express purpose of locating sources of geothermal energy. The principle behind geothermal energy is that heat is extracted from aquifers deep in the earth’s crust for heating buildings. The temperature in suitable layers can be between 55 and 110 degrees Celsius. TU Delft applied for the permit as part of the Delft Geothermal Project (DAP), an initiative of students and alumni of the Applied Earth Sciences programme. The aim of the programme is to do research into geothermal energy and develop teaching programmes focussing on this subject. In addition, the warm water that is extracted from a depth of over 2000 meters can eventually be used to provide university buildings and dormitories with sustainable heating. The university could potentially save 5 million cubic meters of natural gas per year.

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Hierdoor kon het onderzoek gericht op het ontwikkelen van unieke halvegeleidercomponenten waar de samenvoeging van materialen zoals gallium (Ga), arseen (As) en boor (B), met Si en Ge, in een de zelfde reactor, worden bewerkstelligd. Voor het eerst konden depositiecycli met lagen van verschillende combinaties van deze III, IV, V elementen worden uitgevoerd zonder vacuümonderbreking.

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properties. The work presented in this thesis is initiated by this major goal of merging III-V semiconductor technology with Si technology. The focus was primitively placed on development of a Si-compatible tool for chemical vapor deposition (CVD) of gallium arsenide (GaAs). For this purpose, a Si/SiGe CVD reactor, ASMI Epsilon 2000, was extended with a TriMethylGallium (TMGa) bubbler system and extra tubing to allow the deposition of GaAs as well as the standard Si and SiGe depositions. Of key importance was to apply a very low arsine (AsH3) concentration: 0.7% as compared to the at least ten times higher values normally used in MOCVDs. The correspondingly low concentration of TMGa means that the contamination of the reactor chamber with gallium or arsenic is so low that standard high-quality low-doped Si and SiGe depositions can still be performed in the same CVD reactor chamber. In view of this, the research took a unique direction of creating devices where the merging of depositions of gallium (Ga), arsenic (As) and boron (B), together with Si and Ge, all in one reactor, proved indispensable. For the first time, deposition cycles containing layers of different combinations of these III, IV, V elements could then be performed without vacuum break. This was important not only for the growth of good quality GaAs epitaxy and crystalline Ge-on-Si, but also for the formation of junction diodes in these materials. In particular, the formation of p+n Si diodes of exceptional quality was facilitated by deposition of pure gallium (PureGa) or pure boron (PureB) to create the p+-region. The combination of both PureGa and PureB techniques have been implemented on crystalline Ge-on-Si to form ideal Ge-on-Si p+n junctions with world record low saturation currents. The term PureGaB is introduced for this technology.

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Polytype 3R2 heeft een grotere aluminium verhouding vergelijken met de 3R1. Dit aluminium bestaat als tetraëdrische aluminaat ion in de tussenlagen ter compensatie van de lading van de octaëdrische lagen.

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Layered Double Hydroxides (LDH) is a unique group of clays that have an anionic exchange capability. This research explored the hydrothermal method as an alternative method to synthesize Mg-Al LDH. It is a simple and more environmentally friendly compared to the conventional method of co-precipitation. Furthermore, depending on the synthesis condition, two different polytypes, namely 3R1 and 3R2 can be synthesized. The first part of the research was focused on the optimization of the hydrothermal synthesis. Various pre-treatment techniques of the reactants were investigated. The use of a microwave system as an alternative energy source resulted in the formation of a unique donut-shaped crystal which provides enlargement of the specific surface area of the {hk0} faces, needed for adsorption application. The growth mechanism of such donut-like crystals is studied by AFM as well as by STEM-EDX. The interrelation of polytype 3R1 and 3R2 along with the chemical composition and structure of polytype 3R2 is addressed in the second part. The transition temperature is approximately at 110 ºC with 3R1 being stabile at lower temperatures and 3R2 at higher temperatures. Polytype 3R2 was also found to have more aluminum content compared to 3R1. The excess aluminium is the presence as tetrahedrally coordinated aluminate ion located in the interlayer as charge compensation. The apical oxygen of the aluminate is grafted onto the octahedral metal layer, inducing the formation of 3R2 stacking. This grafted structure might explain the reluctance of polytype 3R2 to be ion exchanged compared to 3R1.

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De Flex-to-Rigid (F2R) technologie pakt specifiek de manipulatie en montage problemen aan die voortkomen uit het werken met kleine, ultra-flexibele apparatuur. Bovendien is voor de fabricatie van ultra-flexibele sensoren het openen van hoge-dichtheid via’s in polyimide lagen nodig.

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Being able to measure medical parameters directly inside the body in a minimally invasive way allows for a more accurate, faster, safer and cheaper diagnosis. A typical example can be found in the diagnosis of coronary artery diseases, where simultaneous measurement of intracoronary blood flow and pressure is needed. The aim of this Thesis is to provide the technological means to implement diverse sensing functionalities, such as pressure and flow sensing, at the tip of minimally invasive medical instruments. Because of the cylindrical shape and the small diameter of catheters and guidewires (Ø = 1 mm and 360 µm, respectively), it is almost unavoidable that complex sensing/and or electronics systems must include flexible or foldable parts. FleXss, a Matlab-based graphical user interface was created. It allows a quick and easy analytical modeling of the stress-strain distribution in multilayered devices during and after fabrication, with the possibility to apply external bending. A generic technological platform allowing for the design, fabrication and assembly of partially flexible sensor systems at the tip of minimally invasive medical instruments was also developed. The Flex-to-Rigid (F2R) technology specifically addresses the handling and mounting issues arising when working with small, ultra-flexible devices. Moreover, the fabrication of ultra-flexible sensors requires the opening of high density vias in polyimide coatings. A two-step plasma etching recipe combining both isotropic and anisotropic profiles, resulting in residue-free wine glass shaped vias, was developed. The design of a polyimide-based 5 mm diameter flexible calorimetric flow sensor was optimized in order to fit around a medical guidewire. It was possible to successfully bend the improved flow sensor around a 360 µm wire, by keeping in the tensile plane only structures that are small compared to the bending diameter. All structures that are oriented perpendicular to the bending axis are embedded in the stress neutral plane. Numerical studies showed that the performance of the mechanically improved sensor is similar to the less flexible original device. It was moreover experimentally proven that the constant temperature sensor driving mode is superior to the constant power mode in terms of sensitivity and applicability for in-vivo use.