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991.
992.
An innovative material based on natural rubber and leather tannery waste to be applied as antistatic flooring
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Marcos R. Ruiz Eduardo R. Budemberg Giovanni P. da Cunha Felipe S. Bellucci Helder N. da Cunha Aldo E. Job 《应用聚合物科学杂志》2015,132(3)
In recent decades, the production chain of beef and bovine leather has grown significantly because of an increase in the world's population and improved access to consumption. However, the generation of waste derived from this sector has grown simultaneously, and consequently, improved ways of adding value, reusing, and disposing these waste materials are being sought. In this article, we present a new and innovative composite material based on vulcanized natural rubber (NR), carbon black (CB), and leather waste (NR/CB/leather). The NR/CB/leather composites were prepared by thermal compression with 60 phr of CB and 60 or 80 phr of leather waste. In accordance with Brazilian sanitary laws, we exposed these composites for 24 h to bleach (B) and a disinfectant with the aim of simulating a true everyday cleaning use. The deconvolution of the impedance semicircles was carried out, and two relaxation phenomena around linear relaxation frequencies of about 105 and 106 Hz were found and associated mainly with charge carriers from CB and leather waste. With the addition of leather, the electrical conductivity of the composites increased two orders of magnitude from 5.70 × 10?6 for the NR/CB to 7.97 × 10?4 S/cm for NR/CB/leather‐60 phr B. These results point to the possibility of using these composites as an antistatic flooring once they exhibit acceptable values of electrical conductivity and once they withstand, from the structural, morphological, and electrical point of view, exposure to sanitizing agents. Furthermore, the production of these composites will add value to and enable an environmentally acceptable disposal of leather waste. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41297. 相似文献
993.
Stefania D’Arpa Gianpiero Colangelo Giuseppe Starace Irene Petrosillo Delia Evelina Bruno Vito Uricchio Giovanni Zurlini 《Energy Efficiency》2016,9(5):1065-1085
Greenhouse farming, where energy consumptions are mainly related to the greenhouses heating, is one of the sectors consuming the most energy in the agricultural industry. High costs and the uncertain availability of fossil fuels constrain the use of heating applications. Among possible solutions, the utilization of renewable heating systems such as geothermal energy through ground-source heat pump systems (GSHPs) at competitive prices has to be taken in consideration. The competitiveness of these systems depends mainly on the characteristics of the end-users, i.e., the annual heating loads. Few studies focusing on the potential of using these systems start with an analysis of the thermal requirements and end with a cost evaluation in tune with local assets, geo-climatic conditions, and landscape protection. This paper analyzes the greenhouse crop industry in the Apulia region in southern Italy, as a potential end-user of GSHP systems. Data collected from an area mainly devoted to greenhouse crop production have been used to (a) describe greenhouse farms, (b) define the heating requirements of a greenhouse model representative of the most used typology in the investigated area, and (c) examine the economic viability of greenhouse heating with GSHP systems. Both vertical and horizontal ground heat exchanger (GHE) configurations are compared with conventional fossil-fuel heating systems. In all scenarios considered, the observed payback periods appear reasonable and worthy of consideration. The results suggest that these technologies can fully satisfy the winter heating requirements in a cost-effective way and they can support the planning of measures aimed to improve the sector competitiveness. 相似文献
994.
995.
Maria Tufariello Maria A. Chiriatti Francesco Grieco Carla Perrotta Simonetta Capone Patrizia Rampino Mariana Tristezza Giovanni Mita Francesco Grieco 《LWT》2014
Saccharomyces cerevisiae is the yeast species predominating the alcoholic fermentation of grape must. The aim of this research was to evaluate the impact of indigenous S. cerevisiae strains biodiversity on the aroma of wines from Negroamaro grapes. Grapes collected in two different Negroamaro producing micro districts in Salento (Southern Italy), were subjected to natural fermentation and two indigenous S. cerevisiae populations were isolated. Fifteen strains for each of the two populations were selected and tested by micro fermentation assay in order to evaluate their specific contribute to the volatiles composition and sensory impact of the produced wines. The aromatic profile of wines obtained by each selected strain was characterized by different contents of acetates, ethyl esters of fatty acids, higher alcohols, thus showing to be related to the strains geographical origin. The sensorial analysis of wines produced by the six best performing strains confirmed that they are good candidates as industrial starter cultures, This study indicates that the use of a “microarea-specific” starter culture is a powerful tool to enhance the peculiarity of wines deriving from specific areas. 相似文献
996.
Kamel Agroui George Collins Flamanio Giovanni Wolfang Stark 《Polymer-Plastics Technology and Engineering》2015,54(7):719-729
The goal of this research is to better understand the effect of aging on thermal relaxations, physical properties, and thermo-mechanical properties of the cross-linked EVA. The results suggest that for the aged EVA, recrystallization due to the UV photo-degradation is the dominant physical process occurring during indoor aging. The aged EVA shows clear evidence several additional secondary melting peaks, as well as changes in the main melting region. Higher temperature levels during outdoor exposure caused greater changes in the polymer morphology, which led to stiffening of the polymer and solar cell delamination due to adhesion loss of the packaging system. 相似文献
997.
Sungroh Yoon Luca Benini Giovanni De Micheli 《IEEE transactions on information technology in biomedicine》2007,11(4):493-494
Co-clustering has not been much exploited in biomedical informatics, despite its success in other domains. Most of the previous applications were limited to analyzing gene expression data. We performed co-clustering analysis on other types of data and obtained promising results, as summarized in this paper. 相似文献
998.
Reflection principles in computational logic 总被引:1,自引:0,他引:1
Barklund J; Dell'Acqua P; Costantini S; Lanzarone GA 《Journal of Logic and Computation》2000,10(6):743-786
999.
The deformation recovery at room temperature of a polycarbonate after large tensile deformation and subsequent stress relaxation is measured as a function of time. The effect of the main parameters which affect the amount of recovered deformation is analyzed. This suggests a plot of the recovery versus time curves by means of proper coordinates which allow shifting of all curves towards a single master curve, thus indicating that most of the phenomena involved in the recovery process are taken into account. 相似文献
1000.
Giovanni Bentivenga Maurizio D'Auria Pietro Fedeli Giacomo Mauriello & Rocco Racioppi 《International Journal of Food Science & Technology》2004,39(10):1079-1086
Solid‐phase microextraction gas chromatography‐mass spectrometry analysis of nineteen samples of honey from Basilicata (southern Italy) showed the presence of some flavour components never described before in honey. Furthermore, some phenyl‐substituted hydrocarbons were detected. These compounds may be derived from the wastewater treatment plant in the area. Furthermore, in honey collected near an oil extraction plant, hydrocarbons were found; these may be derived from such plants present in the area. 相似文献