A new transparent Bio-MEMS for uni-axial single cell stretching

A novel, completely transparent bio-MEMS (bio-Micro Electro Mechanical System) device has been devised and manufactured using finite element analysis (FEA) and micro-fabrication techniques. The device has been designed to be used for testing the mechanical properties of single living cells, it is versatile and suitable for coupling with other analysis techniques. Furthermore, being completely transparent, it can be used with either transmission or reflection microscopes. The transparent bio-MEMS is based on a silicon dioxide?Csilicon nitride structure and, since the main goal is to test living cells, it is meant to work in a liquid environment and allow for cell stretching. Sensors for cell deformation and for platform displacement are also present and the required sensitivity for single cell analyses is granted. The device will moreover allow the recording of the stress?Cstrain curve for single living cells.     

Variable-coherence tomography for inverse scattering problems

We propose a technique for determining the pair-correlation function of a quasi-homogeneous medium. The method uses the variation of the spatial-coherence properties of the incident beam to generate two separate volumes of coherence where the field is correlated. Using this specially prepared beam, we reconstruct experimentally the correlation function of a scattering potential by recording the scattered intensity in only one direction.     

Mode analysis of spreading of partially coherent beams propagating through atmospheric turbulence

The spreading of partially coherent beams propagating through atmospheric turbulence is studied by use of the coherent-mode representation of the beams. Specifically, we consider partially coherent Gaussian Schell-model beams entering the atmosphere, and we examine the spreading of each coherent mode, represented by a Hermite-Gaussian function, on propagation. We find that in atmospheric turbulence the relative spreading of higher-order modes is smaller than that of lower-order modes, whereas the relative spreading of all order modes is the same as in free space. This modal behavior successfully explains why under certain circumstances partially coherent beams are less affected by atmospheric turbulence than are fully spatially coherent laser beams.     

Propagation of partially coherent beams through particulate media

When propagating through particulate media, optical beams are degraded owing to scattering. We found that the ratio between the width of the distorted beam and the width of the initial beam decreases when the spatial coherence of the incident beam is reduced. These experimental observations are well described within the paraxial approximation of the transport theory.     

Zusammensetzung italienischer Tomatens?fte

Ohne ZusammenfassungMitteilung aus dem Laboratorio Chimico Municipale in Mailand.     

Micro gas turbine thermodynamic and economic analysis up to 500 kWe size

In this paper a thermoeconomic analysis and optimization of micro gas turbines (MGT) up to 500 kWe is presented. This analysis is strongly related to the need of minimizing specific capital cost, still high for MGT large market penetration, and optimizing MGT size to match market needs.     

Mode coupling approach to beam propagation in atmospheric turbulence

A mode coupling approach based on the modal theory of coherence is suggested for the study of partially coherent beams in atmospheric turbulence. An approximate expression is derived for the mode power coupling coefficients, and some specific cases are studied using numerical methods. Several general results derived from the properties of the coupling coefficients are also presented.     

Pure hydrogen co-production by membrane technology in an IGCC power plant with carbon capture

The CO₂ capture in Integrated Gasification Combined Cycle (IGCC) plants causes a significant increase of the cost of electricity (COE) and thus determines high CO₂ mitigation cost (cost per ton of avoided CO₂ emissions). In this work the economic sustainability of the co-production of pure hydrogen in addition to the electricity production was assessed by detailed process simulations and a techno-economic analysis. To produce pure hydrogen a Water Gas Shift reactor and a Selexol^® process was combined with H₂ selective palladium membranes. This innovative process section was compared with the more conventional Pressure Swing Adsorption in order to produce amount of pure hydrogen up to 20% of the total hydrogen available in the syngas.Assuming for a base case a hydrogen selling price of 3 €/kg and a palladium membrane cost of 9200 €/m², a cost of electricity (COE) of 64 €/MWh and a mitigation cost of 20 €/ton_CO2 were obtained for 90% captured CO₂ and 10% hydrogen recovery. An increase of the hydrogen recovery up to 20% determines a reduction of the COE and of the mitigation cost to 50 €/MWh and 5 €/ton_CO2, respectively. A sensitivity analysis showed that even a 50% increase of cost of the membrane per unit surface could determine a COE increase of only about 10% and a maximum increase of the mitigation cost of further 5 €/ton_CO2.