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Positioning of nanometer-sized particles on flat surfaces by direct deposition from the gas phase

Arrangements of nanometer-sized particles were obtained on plane oxidized silicon substrates by direct deposition from the gas phase. The particles were attracted onto charge patterns created by contact charging. Monodisperse, singly charged indium aerosol particles with a diameter of 30 nm were used as a test case to illustrate this process. Due to the surface treatment, the deposition is highly

Single-crystalline tungsten nanoparticles produced by thermal decomposition of tungsten hexacarbonyl

Nanometer-sized particles of W are of interest in semiconductor device research, where such particles may store electrons inside heteroepitaxially defined structures. In this paper, we present results concerning W particles produced by thermal decomposition of tungsten hexacarbonyl. By the described method, it was possible to produce size-selected, single-crystalline W particles in the size range

Aerosol fabrication of nanocrystals of InP

Nanocrystals of indium phosphide, with diameters of around 10nm, have been produced via an aerosol route. The method is based on the formation of monodisperse indium droplets and the subsequent reaction with phosphine at elevated temperature. The size of the final InP nanocrystal is self-limited by the size of the introduced size-selected In droplet. This size can be tuned carefully, thus this met

Single-electron devices via controlled assembly of designed nanoparticles

Single-electron transistors (SET) rely for their functionality on extreme control of lithography and lateral positioning as well as of properties of the building blocks from which the devices are built. By an aerosol-based nanoparticle fabrication we can prepare nanocrystals down to sub-10nm dimensions with metallic or semiconducting character, as well as having a core + shell design for definitio

Size-selected nanocrystals of III-V semiconductor materials by the aerotaxy method

In this paper we present a fabrication route to produce size-selected III-V semiconductor nanocrystals via a simple, reliable, and efficient aerosol route. Since this approach includes the reaction of aerosol particles and a self-organized growth of a new compound, all in the aerosol phase, we call this process aerotaxy. Size-selected nanocrystals of different III-V compounds in a diameter range b

Lunds domkyrka, det universella rummet

An investigation on the different levels of interpretation of medieval architectural iconography. The architecture and sculpture of Lund cathedral is related to function, history, politics and religion.

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La conferencia plantea la necesidad de un tránsito hacia otras formasde aplicar la semiótica en el diseño.La semiótica del diseño con enfoque agentivo ofrece elementos paraconocer en detalle la experiencia humana y las condiciones que determinanla construcción de sentido que emerge cuando un usuario integra artefactosa dicha experiencia para el cumplimiento de sus objetivos.El asumir un enfoque se

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This research aims to encourage interdisciplinary and inter-institutionalcollaborative work through the design and manufacture of an electricvehicle. The goal is to design an experimental vehicle concept in order toimprove sustainable mobility in Bogotá.Industrial Center of Maintenance and Manufacturing CIMM, SENABoyacá, is manufacturing the prototype designed by the team ofresearchers, while priv

Effect of H2/CO ratio and N2/CO2 dilution rate on laminar burning velocity of syngas investigated by direct measurement and simulation

Laminar burning velocities of syngas/air premixed flames, varying with H2/CO ratio (from 5/95 to 75/25) and N2 or CO2 dilution rate (from 0% to 60%), were accurately measured using a Teflon coated Heat Flux burner and OH-PLIF based Bunsen flame method. Experiments were carried out at atmospheric pressure and room temperature, with fuel/air equivalence ratios ranging from fuel-lean to fuel-rich. Co

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Car-sharing systems with electric vehicles are an alternativeto reduce commuting times in big cities and also to mitigateair pollution. Car-sharing exists in 1100 cities around theworld. These systems have had positive effects in the cities,replacing between 9 and 23 private vehicles for each car. Thisdocument proposes a public car-sharing system for Bogotá.The article focuses on the design and ma

Non-uniform nanosecond gate-delay of hybrid pixel detectors

A simple experiment to characterize the gating properties of X-ray area detectors using pulsed X-ray sources is presented. For a number of time-resolved experiments the gating uniformity of area detectors is important. Relative gating delays between individual modules and readout chips of PILATUS2 series area X-ray detectors have been observed. For three modules of a PILATUS300K-W unit the maximum

Understanding the Intrinsic Surface Reactivity of Single-Layer and Multilayer PdO(101) on Pd(100)

We investigated the intrinsic reactivity of CO on single-layer and multilayer PdO(101) grown on Pd(100) using temperature-programmed reaction spectroscopy (TPRS) and reflection absorption infrared spectroscopy (RAIRS) experiments, as well as density functional theory (DFT) calculations. We find that CO binds more strongly on multilayer than single-layer PdO(101) (∼119 kJ/mol vs 43 kJ/mol), and tha

In situ oxidation study of Pd-Rh nanoparticles on MgAl 2 O 4 (001)

Alloy nanoparticles on oxide supports are widely used as heterogeneous catalysts in reactions involving oxygen. Here we discuss the oxidation behavior of Pd-Rh alloy nanoparticles on MgAl 2 O 4 (001) supports with a particle diameter from 6-11 nm. As an In situ tool, we employed high energy grazing incidence X-ray diffraction at a photon energy of 85 keV. We find that physical vapor deposited Pd-

Atomic structure of Pt nanoclusters supported by graphene/Ir(111) and reversible transformation under CO exposure

We have investigated the atomic structure of graphene/Ir(111) supported platinum clusters with on average fewer than 40 atoms by means of surface x-ray diffraction (SXRD), grazing incidence small angle x-ray scattering (GISAXS), and normal incidence x-ray standing waves (NIXSW) measurements, in comparison with density functional theory calculations (DFT). GISAXS revealed that the clusters with 1.3

Time-Resolved Diffraction Studies of Structural Dynamics in Solids

Studies of the structural dynamics of solids can improve our understanding of atomic motion in materials, and may thus help in the manufacture of new devices or the development of materials with novel structures and properties. Ultrashort laser pulses, a few tens of femtoseconds long, can deliver high energies (mJ–kJ). This energy is absorbed by the electrons in a solid material, leading to a rapi