A survey of ellagitannin content in raspberry and blackberry cultivars grown in Trentino (Italy)

This study describes the first application of a new procedure for acid hydrolysis of Rubus ellagitannins in methanol, which allows quantification of all the major reaction products (ellagic acid, methyl-sanguisorboate, methyl gallate and an unknown ellagic acid derivative) and estimation of the mean degree of polymerization (mDP) of Rubus ellagitannins. The ellagitannins of 21 raspberry and 15 blackberry cultivars produced in Trentino, Italy during 2005 were extracted and characterised. The total content of ellagitannins was shown to vary by a factor of 2 among raspberry cultivars and by a factor of 4 among blackberry cultivars.     

Viscosimetric studies on 2-methoxyethanol + 1,2-dimethoxyethane binary mixtures from −10 to 80°c

The kinematic viscosities (v) were measured for nine binary solvent mixtures of 2-methoxyethanol (ME) + 1,2-dimethoxyethane (DME) at nineteen temperatures ranging from ?10 to +80°C. The experimental data have been used to test some empirical equations of the type v = v(T), v = v(X₁) and v = v(T, X₁). The viscosities of all the mixtures increase from the values of pure DME to that of ME as the mole fraction of ME increases, and always yield a negative excess property (v^E) at all the investigated temperatures. Furthermore, thermodynamic parameters of viscous flow have been evaluated on the basis of the Eyring theory. The excess free energy of activation of viscous flow (ΔG^E) vs X₂ plot suggests the presence of a stable hetero-adduct, having ME : DME = 1 : 1 stoichiometric ratio.     

The Release Rate of Indomethacin from Solid Dispersions with Eudragite

The coprecipitates were prepared by a solvent technique using Eudragit E as carrier and indomethacin as a model drug.

X-Ray diffractometry, differential scanning calorimetry (DSC) and wettability tests were employed to investigate the physical state of the studied formulations. Up to 50% of indomethacin can be dispersed in an amorphous state in Eudragit E.

The influence of the pH on the in vitro release of solid dispersions has been evaluated. Because of the good solubility of Eudragit E at pH 1.2 a fast dissolution rate of the drug was observed while a marked delay was noticed at pH 7.5 where the polymer is only permeable to water. At pH 5.8 the kinetics of drug release can be modulated by the drug/polymer ratio. The dissolution rate of the drug can be increased by decreasing its amount in the coevaporate.     

Integration of InGaP/GaAs/Ge triple‐junction solar cells on deeply patterned silicon substrates

We report preliminary results on InGaP/InGaAs/Ge photovoltaic cells for concentrated terrestrial applications, monolithically integrated on engineered Si(001) substrates. Cells deposited on planar Ge/Si(001) epilayers, grown by plasma‐enhanced chemical vapor deposition, provide good efficiency and spectral response, despite the small thickness of the Ge epilayers and a threading dislocation density as large as 10⁷/cm². The presence of microcracks generated by the thermal misfit is compensated by a dense collection grid that avoids insulated areas. In order to avoid the excessive shadowing introduced by the use of a dense grid, the crack density needs to be lowered. Here, we show that deep patterning of the Si substrate in blocks can be an option, provided that a continuous Ge layer is formed at the top, and it is suitably planarized before the metalorganic chemical vapor deposition. The crack density is effectively decreased, despite that the efficiency is also lowered with respect to unpatterned devices. The reasons of this efficiency reduction are discussed, and a strategy for improvement is proposed and explored. Full morphological analysis of the coalesced Ge blocks is reported, and the final devices are tested under concentrated AM1.5D spectrum. Copyright © 2016 John Wiley & Sons, Ltd.     

Impact of deposit aging and surface roughness on thermal fouling: Distributed model

A kinetic model was recently proposed to describe the effect of aging on deposit thermal conductivity and the thermal performance of a shell‐and‐tube heat exchanger undergoing crude oil fouling. The model is adapted for implementation within a dynamic, distributed system with spatial and temporal distributions, relaxing several of the previous assumptions. The evolution of surface roughness is also considered, using conjectural linear and asymptotic functions. Simulations are performed for a single tube representative of a refinery exchanger. The results demonstrate the substantial effects over time of aging and roughness on heat transfer and pressure drop. Roughness effects yield apparently negative initial fouling resistances, as reported in some experimental tests. The importance of accounting for roughness dynamics in short time scale pilot plant scale tests and aging over longer time scales in industrial applications is highlighted. © 2010 American Institute of Chemical Engineers AIChE J, 2010     

ADECO full-face tunnel excavation of two 260 m tubes in clays with sub-horizontal jet-grouting under minimal urban cover

With a cover of 5-30 m, a 260 m² cross-sectional area, and a 4-m wide pillar, the Cassia twin road tunnels underpass Cassia road (main road to/from Rome), the remnants of a 2000 year-old Roman villa, and two existing tunnels. Stiff silty clay dominates the alignment. According to the Analysis of Controlled DEformations (ADECO) principles, each tube was excavated full face to 260 m². Compared to Sequential Excavation Method (SEM), this highly simplifies construction, leads to construction industrialization, and allows for full control of the ground ahead of the face, which is used as a stabilization measure. In order to pre-confine the tunnel core, Trevi roto-injection technique was used to create an umbrella of overlapping sub-horizontal reinforced jet-grouting columns ahead of the face, while avoiding up heave of the ground or emptying of the columns. Stiff preliminary lining sitting on sub-horizontal jet-grouting columns, final invert close to the tunnel face, and final lining no more than 50 m behind the face ensured that the pre-confinement ahead of the tunnel face became effective confinement around the cavity. The tunnels were finished on schedule and within budget with a mere 1 cm of settlement.     

Updating of a DRASTIC-based Method for Specific Vulnerability Assessment in Carbonate Aquifers

Abstract

Some methodological modifications are suggested to improve a DRASTIC-based method as a reliable predictor of microbial contamination in extensively fractured and subordinately karstified carbonate aquifers. These modifications will allow a better assessment of vulnerability induced by the concentrated infiltration of surface runoff in two different scenarios: (a) when the karst system is entirely located within an unsaturated aquifer and (b) when the karst system is partially located within a saturated medium. The effectiveness of the updated method has been experimentally verified by comparing the vulnerability values with the results of a hydrogeological and microbiological study at a test site.