1,720,981 research outputs found
Laser Processing in the Manufacture of Dye-Sensitized and Perovskite Solar Cell Technologies
No full textDye-sensitized and perovskite solar cells have seen tremendous efforts in their development in recent years. Amongst these developments are the design and implementation of fabrication techniques that can guarantee high performance as well as scalability over large areas. Laser processing has become a versatile and important tool in many industries and has also been applied successfully to both types of solar cell technologies, culminating in the demonstration of dye solar devices where all temperature treatments have been replaced with laser techniques, and of high-performance solid-state perovskite modules. Herein, we introduce concepts and review the available literature, pertaining to the effective utilization of laser beams for the development of both dye-sensitized and perovskite photovoltaic technologies
Process of manufacturing of the catalytic layer of the counter-electrodes of dye-sensitized solar cells. - Procedimento di fabbricazione dello strato catalitico dei controelettrodi di celle foto elettrochimiche (CURING LASER).
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Double- and multi-femtosecond pulses produced by birefringent crystals for the generation of 2D laser-induced structures on a stainless steel surface
Full text linkLaser-induced textures have been proven to be excellent solutions for modifying wetting, friction, biocompatibility, and optical properties of solids. The possibility to generate 2D-submicron morphologies by laser processing has been demonstrated recently. Employing double-pulse irradiation, it is possible to control the induced structures and to fabricate novel and more complex 2D-textures. Nevertheless, double-pulse irradiation often implies the use of sophisticated setups for modifying the pulse polarization and temporal profile. Here, we show the generation of homogeneous 2D-LIPSS (laser-induced periodic surface structures) over large areas utilizing a simple array of birefringent crystals. Linearly and circularly polarized pulses were applied, and the optimum process window was defined for both. The results are compared to previous studies, which include a delay line, and the reproducibility between the two techniques is validated. As a result of a systematic study of the process parameters, the obtained morphology was found to depend both on the interplay between fluence and inter-pulse delay, as well as on the number of incident pulses. The obtained structures were characterized via SEM (scanning electron microscopy) and atomic force microscopy. We believe that our results represent a novel approach to surface structuring, primed for introduction in an industrial environment
Sintering process of metal oxide based formulations. - Procedimento di sinterizzazione di formulazioni a base di ossidi metallici.
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Blocking layer optimisation of poly(3-hexylthiopene) based Solid State Dye Sensitized Solar Cells
Full text linkThe optimisation study of the fabrication of a compact TiO2 blocking layer (via Spray Pyrolysis
Deposition) for poly(3-hexylthiopene) (P3HT) for Solid State Dye Sensitized Solar Cells
(SDSCs) is reported. We used a novel spray TiO2 precursor solution composition obtained
by adding acetylacetone to a conventional formulation (Diisopropoxytitanium bis(acetylacetonate)
in ethanol). By Scanning Electron Microscopy a TiO2 layer with compact morphology
and thickness of around 100 nmis shown. Through a Tafel plot analysis an enhancement of the
device diode-like behaviour induced by the acetylacetone blocking layer respect to the conventional
one is observed. Significantly, the device fabricatedwith the acetylacetone blocking
layer shows an overall increment of the cell performance with respect to the cellwith the conventional
one (DJsc/Jsc = +13.8%, DFF/FF = +39.7%, DPCE/PCE = +55.6%). A conversion efficiency
optimumis found for 15 successive spray cycles where the diode-like behaviour of the acetylacetone
blocking layer is more effective. Over three batches of cells (fabricated with P3HT and
dye D35) an average conversion efficiency value of 3.9% (under a class A sun simulator with 1
sun A.M. 1.5 illumination conditions) was measured. From the best cell we fabricated a conversion
efficiency value of 4.5% was extracted. This represents a significant increment with
respect to previously reported values for P3HT/dye D35 based SDSCs
- …
