| 1. |
- Bianchi, F., et al.
(författare)
-
Characterisation of the volatile profile of orange juice contaminated with Alicyclobacillus acidoterrestris
- 2010
-
Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 123:3, s. 653-658
-
Tidskriftsartikel (refereegranskat)abstract
- A rapid and reliable analytical method, based on the characterisation of the volatile profile by dynamic headspace extraction followed by gas chromatography mass-spectrometry, was developed in order to early detect Alicyclobacillus acidoterrestris spoilage in orange juice. Gas chromatographic peak areas were submitted to multivariate statistical analysis (principal component and linear discriminant analysis) in order to visualise clusters within samples and to detect the volatile compounds able to differentiate contaminated from not-contaminated samples. Significant differences in the volatile profile of the analysed samples were found, assessing the reliability of the proposed method to detect the A. acidoterrestris contamination in orange juice.Neither guaiacol nor 2,6-dibromophenol, usually regarded as A. acidoterrestris contamination markers, were detected in the analysed samples.
|
|
| 2. |
- Braga, Antonio, et al.
(författare)
-
Panchromatic sensitized solar cells based on metal sulfide quantum dots grown directly on nanostructured TiO2 electrodes
- 2011
-
Ingår i: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 2:5, s. 454-460
-
Tidskriftsartikel (refereegranskat)abstract
- The use of narrow band gap semiconductors such as PbS may expand the light absorption range to the near-infrared region in quantum-dot-sensitized solar cells (QDSCs), increasing the generated photocurrent. However, the application of PbS as a sensitizer in QDSCs causes some problems of stability and high recombination. Here, we show that the direct growth of a CdS coating layer on previously deposited PbS by the simple method of successive ionic layer adsorption and reaction (SILAR) minimizes these problems. A remarkable short-circuit current density for PbS/CdS QDSCs is demonstrated, ∼11 mA/cm2, compared to that of PbS QDSCs, with photocurrents lower than 4 mA/cm2, using polysulfide electrolyte in both cells. The cell efficiency reached a promising 2.21% under 1 sun of simulated irradiation (AM1.5G, 100 mW/cm2). Enhancement of the solar cell performance beyond the arithmetic addition of the efficiencies of the single constituents (PbS and CdS) is demonstrated for the nanocomposite PbS/CdS configuration. PbS dramatically increases the obtained photocurrents, and the CdS coating stabilizes the solar cell behavior. © 2011 American Chemical Society.
|
|
| 3. |
- Comini, Elisabetta, et al.
(författare)
-
Metal oxide nanoscience and nanotechnology for chemical sensors
- 2013
-
Ingår i: Sensors and actuators. B, Chemical. - : Elsevier BV. - 0925-4005 .- 1873-3077. ; 179, s. 3-20
-
Tidskriftsartikel (refereegranskat)abstract
- This paper focuses on the capabilities and development prospects of nanostructured metal oxides (MOX) representing the most versatile and richest class of materials in terms of electronic structure and structural, chemical, and physical properties. MOX nano-materials with controlled composition, surface terminations, and crystalline structures to be used as chemical sensors as a new area in analytical chemistry and instrument engineering are discussed. Their principles of operation, and basic characteristics are outlined and main applications of MOX sensor technology are presented. © 2012 Elsevier B.V. All rights reserved.
|
|
| 4. |
- Concina, Isabella, et al.
(författare)
-
Alicyclobacillus spp Detection in soft drinks by Electronic Nose
- 2010
-
Ingår i: Food Research International. - : Elsevier BV. - 0963-9969 .- 1873-7145. ; 43:8, s. 2108-214
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper the skill of an electronic nose to early diagnose the natural contamination by Alicyclobacillus spp in commercial flavoured drinks is presented The instrument was able to identify contaminated products at very low bacterial loads (tens of copies/ml) with an excellent classification rate (almost 100%) The identification of Alicyclobacillus spp by means of the electronic nose was not based on the analysis of the secondary metabolites as it is done by classical analytical techniques thus allowing a surprising capability in recognising the contaminated products at early stage of growth This study strongly suggests the use of the Electronic Noses as screening tools in industrial quality control laboratories but at the same time it underlines some limits still present in the technology
|
|
| 5. |
|
|
| 6. |
- Concina, Isabella, et al.
(författare)
-
Electronic Noses As Flexible Tools For Evaluating Food Quality And Safety : Can We Trust Them?
- 2011
-
Ingår i: OLFACTION AND ELECTRONIC NOSE. - : AIP. ; , s. 109-110
-
Konferensbidrag (refereegranskat)abstract
- Since most food adulterations are reflected on volatile chemical profile, Electronic Noses (ENs) appear as excellent candidates for process monitoring, freshness evaluation, shelf-life investigation, sensory and authenticity assessment, microbial contamination diagnosis [1]. In this study three applications recently carried out in our laboratory are presented and discussed, with the aim to illustrate three paradigmatic and diverse issues related to food quality control in which EN can find application and discuss the reliability of sensor technology in food analysis.
|
|
| 7. |
- Concina, Isabella, et al.
(författare)
-
Electronic noses as flexible tools to assess food quality and safety : Should we trust them?
- 2012
-
Ingår i: IEEE Sensors Journal. - 1530-437X .- 1558-1748. ; 12:11, s. 3232-3237
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents three different applications of an electronic nose (EN) based on a metal oxide sensor array, in order to illustrate the broad spectrum of potential uses of the technique in food quality control. The following scenarios are considered: 1) the screening of a typical error that may occur during the processing of tomato pulp, which leads to sensory damage of the product; 2) the detection of microbial contamination by Alicyclobacillus spp. (ACB) affecting soft drinks; and 3) the proof of evidence of extra virgin olive oil fraudulently adulterated with hazelnut oil. In each case, the EN is able to identify the spoiled product by means of the alterations in the pattern of volatile compounds, reconstructed by principal component analysis of the sensor responses.
|
|
| 8. |
- Concina, Isabella, et al.
(författare)
-
Engineering metal oxide structures for efficient photovoltaic devices
- 2014
-
Ingår i: Oxide-based materials and devices V. - Bellingham, Wash. : SPIE - International Society for Optical Engineering. - 9780819499004
-
Konferensbidrag (refereegranskat)abstract
- Metal oxide-based photoanodes are critical components of dye sensitized solar cells (DSSCs), which are photoelectrochemical cells for the conversion of solar energy, promising to have several benefits as compared with their traditional counterparts. A careful engineering of the wide band gap metal oxide composing the photoanode, as well as their process design, is strategic for improving device performances and for planning a near future production scale up, especially devoted to reducing the environmental impact of the device fabrication. Herein, we present the application of ZnO hierarchical structures as efficient materials to be applied as photoanodes in DSSC, in the perspective of looking for alternative to TiO2 nanoparticles, currently the most exploited metal oxide in these devices. © 2014 SPIE.
|
|
| 9. |
|
|
| 10. |
- Concina, Isabella, et al.
(författare)
-
Light harvester band gap engineering in excitonic solar cells : A case study on semiconducting quantum dots sensitized rainbow solar cells
- 2014
-
Ingår i: Pure and Applied Chemistry. - : Walter de Gruyter GmbH. - 0033-4545 .- 1365-3075. ; 86:5, s. 575-584
-
Tidskriftsartikel (refereegranskat)abstract
- A systematic study on the fabrication of quantum dots sensitized solar cells (QDSSCs) exploiting hybrid networks of semiconducting light harvesters is presented, which shows how the engineering of band gaps of the device components by a very simple technique allows improving the solar energy conversion performances. Panchromatic devices are fabricated and tested, and correspondent functional parameters analyzed in order to highlight both advantages and drawbacks of the most common (CdS, CdSe, PbS) quantum dots applied for light collection in QDSSCs. Judicious engineering of the light harvester layer is demonstrated as a simple and powerful strategy for boosting device performances, through the management of light collection in a rather broad range of solar spectrum and photogenerated charges injection and collection. © 2014 IUPAC & De Gruyter.
|
|
