76 research outputs found
Microbiological and chemical monitoring of Marsala base wine obtained by spontaneous fermentation during large-scale production
The present work was undertaken to evaluate the effect of the natural winemaking on
the microbial and chemical composition of Marsala base wine. To this purpose, a
large-scale vinification process of Grillo grape cultivar was monitored from harvesting
to the final product. Total yeasts (TY) showed a rapid increase after must pressing and
reached values almost superimposable to those registered during the conventional
winemakings. Lactic acid bacteria (LAB) were registered at the highest levels
simultaneously to yeast growth at the beginning of the process. Saccharomyces
cerevisiae was the species found at the highest concentrations in all samples
analysed. Several strains (n= 16) was registered at high levels during the alcoholic
fermentation and/or aging of wine; only two of them were detected on the grape
surface. Lactobacillus plantarum was the LAB species most frequently isolated during
the entire vinification process. Ethanol content was approximately 14% (v/v) at the end
of vinification. The value of pH did not greatly vary during the process and the volatile
acidity (VA) was detected at low concentrations during the entire transformation. The
concentration of malic acid rapidly decreased during the AF; on the other hand, lactic
acid showed an irregular trend during the entire process. trans-caffeil tartaric acid was
the most abundant hydroxycinnamoyl tartaric acid and volatile organic compounds
(VOC) were mainly represented by isoamylic alcohol and isobutanol
Chemical vapour deposition synthetic diamond: materials, technology and applications
Substantial developments have been achieved in the synthesis of chemical
vapour deposition (CVD) diamond in recent years, providing engineers and
designers with access to a large range of new diamond materials. CVD diamond
has a number of outstanding material properties that can enable exceptional
performance in applications as diverse as medical diagnostics, water treatment,
radiation detection, high power electronics, consumer audio, magnetometry and
novel lasers. Often the material is synthesized in planar form, however
non-planar geometries are also possible and enable a number of key
applications. This article reviews the material properties and characteristics
of single crystal and polycrystalline CVD diamond, and how these can be
utilized, focusing particularly on optics, electronics and electrochemistry. It
also summarizes how CVD diamond can be tailored for specific applications,
based on the ability to synthesize a consistent and engineered high performance
product.Comment: 51 pages, 16 figure
Integrated systems for biopolymers and bioenergy production from organic waste and by-products: a review of microbial processes
Advanced Inorganic Structural Fiber Composites IV, Advances in Science and Technology 40
Patterned 2D and 3D assemblies of nanoparticles on molecular printboards
Functionalized nanoparticles have powerful applications as intermediates between solution and surface chemistry and as tools for nanofabrication. Two main examples of these have been shown. The functionalization of 3 nm gold and 55 nm silica nanoparticles with cyclodextrin (CD) host sites has been achieved, which allows: (i) the controlled aggregation with guestfunctionalized dendrimers in solution, (ii) the specific adsorption onto dendrimer-patterned substrates, and (iii) the fabrication of larger architectures using the layer-by-layer methodology. Aggregation in solution was shown to proceed through specific host-guest recognition. The adsorption onto surfaces employed so-called “molecular printboards”, which are self-assembled monolayers with the same cyclodextrin host recognition sites which allow the stable assembly of molecules and nanoparticles through multivalent host-guest interactions. CD silica nanoparticles were shown to adsorb specifically onto areas of such molecular printboards which were patterned with adamantyl-functionalized dendrimers. The layer-by-layer (LBL) assembly of such dendrimers and CD gold nanoparticles led to a controllable multilayer architecture with a thickness increase of about 2 nm per bilayer. The combination of the (bottom-up) particle LBL assembly and top-down surface structuring, in particular nanoimprint lithography, was shown to result in the formation of 3D objects down to sub-100 nm in all three dimensions
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