Search results for " characterization"

The nickel-support interaction as determining factor of the selectivity to ethylene in the oxidative dehydrogenation of ethane over nickel oxide/alum…

2021

[EN] Nickel oxides supported on gamma-alumina (Ni-loading from 5 to 30 wt% NiO) have been synthesized and tested in the oxidative dehydrogenation (ODH) of ethane in order to determine the importance of the NiO-support interaction. The best performance was achieved by the catalyst with 15 wt% NiO; higher NiO-loadings lead to the formation of unselective bulk-like NiO and lower Ni-loadings present high proportion of free alumina surface sites. The presence of oxalic acid and/or niobium in the synthesis gel resulted in the formation of NiO particles with similar size, but higher crystallinity and reducibility than the standard 15 wt% NiO catalyst. The obtained results have revealed that, in ad…

(Photo)catalyst characterization techniques: Adsorption isotherms and BET, SEM, FTIR, UV-Vis, photoluminescence, and electrochemical characterizations

2019

This chapter reports on some characterization techniques that are commonly used for catalysts and photocatalysts. Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), UV-visible (UV-Vis), photoluminescence (PL), and electrochemical characterization techniques are presented with experimental details and actual case studies from literature are discussed. The chapter starts with adsorption phenomena on (photo)catalysis and adsorption isotherms are presented. Then BET analysis technique and its applications in (photo)catalysis are explained. Morphological properties (SEM), functional groups, and the interaction of substrate (and inter…

Label swapper device for spectral amplitude coded optical packet networks monolithically integrated on InP

2011

In this paper the design, fabrication and experimental characterization of an spectral amplitude coded (SAC) optical label swapper monolithically integrated on Indium Phosphide (InP) is presented. The device has a footprint of 4.8x1.5 mm 2 and is able to perform label swapping operations required in SAC at a speed of 155 Mbps. The device was manufactured in InP using a multiple purpose generic integration scheme. Compared to previous SAC label swapper demonstrations, using discrete component assembly, this label swapper chip operates two order of magnitudes faster. © 2011 Optical Society of America.

Electrical characterization of deoxyribonucleic acid hybridization in metal-oxide-semiconductor-like structures

2012

In this work, metal-oxide-semiconductor (MOS)-like sensors in which deoxyribonucleic acid (DNA) strands are covalently immobilized either on Si oxide or on a gold surface were electrically characterized. Si oxide fabrication process allowed us to have a surface insensitive to the solution pH. A significant shift in the flat band voltage was measured after single strand DNA immobilization (+0.47 +/- 0.04 V) and after the complementary strand binding (+0.07 +/- 0.02 V). The results show that DNA sensing can be performed using a MOS structure which can be easily integrated in a more complex design, thus avoiding the problems related to the integration of micro-electrochemical cells.

Multifunctional biosourced materials : durability of unidirectional recycled matrix composites reinforced with flax fibers

2022

Now more than ever, many engineering sectors are turning to natural fiber composites because of the need for more environmentally friendly solutions. One of the main challenges in developing the use of biocomposites in outdoor applications is the lack of knowledge about their long-term durability. The main objective of this work is to provide a better understanding of the mechanisms involved in photooxidative aging of unidirectional composites made of a virgin or recycled polypropylene matrix, reinforced with long flax fibers. In addition, this work aims to study the potential use of a recycled matrix by comparing the evolution of its behavior to photooxidative aging with a virgin matrix. T…

Seasonal characterization of nutritional and antioxidant properties of Opuntia ficus-indica [(L.) Mill.] mucilage

2021

Abstract Opuntia ficus-indica fruit and cladodes are a source of mucilage, a carbohydrate complex, as well as of phytochemicals and other nutrients, useful in the food industry. Despite the environmental-based composition variability has been studied, there is no information on its seasonal variability, which is particularly important for its industrial use. In this study, some technological, nutritional, and bioactive properties of O. ficus-indica cladodes mucilage were analyzed during the seasonal growth period. Total proteins did not change during the whole period and the lipid content significantly decreased from winter to the onset of summer. The fatty acid profile showed high levels o…

The Girgentana Goat Breed: A Zootechnical Overview on Genetics, Nutrition and Dairy Production Aspects

2017

In recent years, there has been a great interest in recovering and preserving local livestock breeds. An interesting situation is represented by the Girgentana goat, an ancient local breed reared in Sicily. Over recent years, this breed has become almost extinct, in part as a consequence of the marked decrease in fresh goat milk consumption. On the basis of these considerations, several studies on its genetic structure and management aspects have been conducted in order to protect the Girgentana goat from the risk of extinction and recover its genetic and economic value. In this context, information on genetics, nutrition and dairy production aspects may have a crucial role in the improveme…

The effect of body shape and gender on wireless Body Area Network on-body channels

2010

Technological advancements have made possible the emergence of Body Area Networks (BANs). There are numerous on-body channel characterizations in the literature performed on a phantom or a single human subject. In this paper, using multiple subjects, we consider the effect of body shape and gender on the on-body channel. A characterization of a narrowband on-body to on-body channel among different subjects is presented. The paper investigates the relationship between the propagation and the subject's physical characteristics. The investigation is performed at 2360 MHz; the new medical band undergoing FCC approval. Our results show that the path loss in women is less than that in men and the…

The Odd Sibling: Features ofβ3-Adrenoceptor Pharmacology

2014

beta(3)-Adrenoceptor agonists have recently been introduced for the treatment of overactive urinary bladder syndrome. Their target, the beta(3)-adrenoceptor, was discovered much later than beta(1)- and beta(2)-adrenoceptors and exhibits unique properties which make extrapolation of findings from the other two subtypes difficult and the beta(3)-adrenoceptor a less-understood subtype. This article discusses three aspects of beta(3)-adrenoceptor pharmacology. First, the ligand-recognition profile of beta(3)-adrenoceptors differs considerably from that of the other two subtypes, i.e., many antagonists considered as nonselective actually are beta(3)-sparing, including propranolol or nadolol. Man…

Il miglioramento energetico nel recupero degli edifici storici. Applicazione al patrimonio architettonico palermitano

L'architettura storica può assumere un ruolo rilevante nel raggiungimento degli obiettivi europei di efficienza energetica per il settore edile, obiettivi che, tuttavia, devono essere compatibili con la conservazione del patrimonio storico e del suo valore culturale. A tal fine è necessario far riferimento ai caratteri specifici dell'architettura storica e alla sua dimensione locale. La presente tesi, sulla base di tale assunto, esamina le prestazioni energetiche degli edifici storici e il loro potenziale miglioramento, concentrandosi sul patrimonio architettonico di Palermo, caso di studio significativo per l'area mediterranea. La ricerca, condotta con riferimento sia alla scala urbana sia…