13,652 research outputs found
Design of a spiral-shaped Mach Zehnder interferometric sensor for refractive index sensing of watery solutions
The design of a spiral-shaped Mach-Zehnder Interferometric sensor (sMZI sensor) for refractive index sensing of watery solutions is presented. The goal of the running project is to realise a multi-sensing array by placing multiple sMZIs in series to form a sensing branch, and to place several sensing branches in parallel. In such an arrangment it is possible to use a single light source for several sensors. Each sensor will contain an electro-optical modulator, which makes it possible to separately interrogate and accurately read-out each sensor in the same sensing branch
Depletion-induced biaxial nematic states of boardlike particles
With the aim of investigating the stability conditions of biaxial nematic
liquid crystals, we study the effect of adding a non-adsorbing ideal depletant
on the phase behavior of colloidal hard boardlike particles. We take into
account the presence of the depletant by introducing an effective depletion
attraction between a pair of boardlike particles. At fixed depletant fugacity,
the stable liquid crystal phase is determined through a mean-field theory with
restricted orientations. Interestingly, we predict that for slightly elongated
boardlike particles a critical depletant density exists, where the system
undergoes a direct transition from an isotropic liquid to a biaxial nematic
phase. As a consequence, by tuning the depletant density, an easy experimental
control parameter, one can stabilize states of high biaxial nematic order even
when these states are unstable for pure systems of boardlike particles
Sellers' hedging incentives at EPA's emission trading auction
Cason (1993)argued thattheauction theEPAused in order to start the market for sulfur allowances, is not efficient. The set-up of the auction gives both buyers and sellers an incentive to understate their valuation of an allowance. In this paper, we show that the sellers’ incentives are even more perverse than Cason suggested. In particular, we show that sellers have an incentive to set their ask price equal to zero, while simultaneously hedging their bets by submitting a positive bid. It is not possible to derive the Nash equilibrium for this set-up. If such an equilibrium exists, sellers either set only a positive ask price, or an ask price equal to zero, and a positive bid as well.
Nano-flow thermal sensor applying dymamic w-2w sensing method
This article presents microchannel thermal flow sensors fabricated using standard micromachining technology. The sensors comprise of a SiXNY microchannel created by etching of a poly-Si sacrificial layer. The channels are released by KOH etching through inlets and outlets etched from the backside of the substrate. Liquid flow is measured by platinum resistors deposited on top of the microchannel, while the channel is thermally isolated from the substrate by a SiXNY membrane. Flow rates of DI water in the order of nlâ‹…min-1 have been measured using a dynamic sensing method applying heat waves
Free Minimization of the Fundamental Measure Theory Functional: Freezing of Parallel Hard Squares and Cubes
Due to remarkable advances in colloid synthesis techniques, systems of
squares and cubes, once an academic abstraction for theorists and simulators,
are nowadays an experimental reality. By means of a free minimization of the
free-energy functional, we apply Fundamental Measure Theory to analyze the
phase behavior of parallel hard squares and hard cubes. We compare our results
with those obtained by the traditional approach based on the Gaussian
parameterization, finding small deviations and good overall agreement between
the two methods. For hard squares our predictions feature at intermediate
packing fraction a smectic phase, which is however expected to be unstable due
to thermal fluctuations. This implies that for hard squares the theory predicts
either a vacancy-rich second-order transition or a vacancy-poor weakly
first-order phase transition at higher density. In accordance with previous
studies, a second-order transition with a high vacancy concentration is
predicted for hard cubes
A spiral-shaped mach-zehnder interferometric sensor for monitoring thickness changes in bioreceptor layers
Design issues of a spiral-shaped Mach-Zehnder interferometer are discussed
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