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11.
12.
Exploring laccase and mediators behavior during saccharification and fermentation of steam‐exploded wheat straw for bioethanol production
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Sara Bagherifard Gianluca Roscioli Maria Vittoria Zuccoli Mehdi Hadi Gaetano D’Elia Ali Gökhan Demir Barbara Previtali Ján Kondás Mario Guagliano 《Journal of Thermal Spray Technology》2017,26(7):1517-1526
Cold spray offers the possibility of obtaining almost zero-porosity buildups with no theoretical limit to the thickness. Moreover, cold spray can eliminate particle melting, evaporation, crystallization, grain growth, unwanted oxidation, undesirable phases and thermally induced tensile residual stresses. Such characteristics can boost its potential to be used as an additive manufacturing technique. Indeed, deposition via cold spray is recently finding its path toward fabrication of freeform components since it can address the common challenges of powder-bed additive manufacturing techniques including major size constraints, deposition rate limitations and high process temperature. Herein, we prepared nickel-based superalloy Inconel 718 samples with cold spray technique and compared them with similar samples fabricated by selective laser melting method. The samples fabricated using both methods were characterized in terms of mechanical strength, microstructural and porosity characteristics, Vickers microhardness and residual stresses distribution. Different heat treatment cycles were applied to the cold-sprayed samples in order to enhance their mechanical characteristics. The obtained data confirm that cold spray technique can be used as a complementary additive manufacturing method for fabrication of high-quality freestanding components where higher deposition rate, larger final size and lower fabrication temperatures are desired. 相似文献
14.
Alkaline or alkaline earth octahydrotriborate M(B3H8)x and dodecahydro-closo-dodecaborate MxB12H12 (M = Li, Na, Mg or Ca with x = 1 or 2) have recently attracted a lot of interest for hydrogen storage and solid electrolyte applications. Nevertheless, their syntheses are still a roadblock for large scale applications. In this paper we propose a novel approach for their syntheses starting from the cheapest borohydride NaBH4. The process involves first the solvothermal synthesis of tetrabutylammonium octahydrotriborate (C4H9)4NB3H8 (TBAB3H8) being the basis for the syntheses of the others boranes. Starting from TBAB3H8, we have synthesized pure and unsolvated NaB3H8 by salt metathesis reaction with sodium tetraphenylborate. Then, we have successfully obtained Na2B12H12 by solvothermal decomposition of NaB3H8. This approach has shown to be quantitative and reproducible, which could lead to the development of these boranes in real life applications. 相似文献
15.
Daniele Viciani Lorella Dell’Olmo Antonio Gabellini Daniela Gigante Lorenzo Lastrucci 《Landscape Research》2018,43(7):952-964
Widespread trends of abandonment have strongly affected Mediterranean mountains after the Second World War, triggering spontaneous recolonisation of forests. A diachronic analysis of the landscape in a Natura 2000 site (Tuscany, Italy) was carried out using digital aerial photographs (1954, 2013) and a GIS-based methodology, focusing on territories above 1300 m a.s.l. The detected variations of total areas, patch shape, patch dimensions and selected metrics showed a notable shift of the vegetation towards woody types and a drastic reduction of open grasslands, some with high conservation value, accompanied by a strong increase in patch number, surface and edge. A decrease of SDI and SEI diversity indices was also observed. Considering that fragmentation is one of the main causes threatening habitats and species, our results point out a clear necessity for a monitoring programme and suitable actions aimed at improving the status of biodiversity-rich montane grasslands. 相似文献
16.
Engineered articular cartilage: influence of the scaffold on cell phenotype and proliferation 总被引:2,自引:0,他引:2
Gigante A Bevilacqua C Cappella M Manzotti S Greco F 《Journal of materials science. Materials in medicine》2003,14(8):713-716
Articular cartilage defects do not heal. Biodegradable scaffolds have been studied for cartilage engineering in order to implant autologous chondrocytes and help cartilage repair. We tested some new collagen matrices differing in collagen type, origin, structure and methods of extraction and purification, and compared the behavior of human chondrocytes cultured on them. Human chondrocytes were grown for three weeks on four different equine type I collagen matrices, one type I, III porcine collagen matrix and one porcine type II collagen matrix. After 21 days, samples were subjected to histochemical, immunohistochemical and histomorphometric analysis to study phenotype expression and cell adhesion. At 7, 14 and 21 days cell proliferation was studied by incorporation of [3H]-thymidine. Our data evidence that the collagen type influences cell morphology, adhesion and growth; indeed, cellularity and rate of proliferation were significantly higher and cells were rounder on the collagen II matrix than on either of the collagen I matrices. Among the collagen I matrices, we observed a great variability in terms of cell adhesion and proliferation. The present study allowed us to identify one type I collagen matrix and one type II collagen matrix that could be usefully employed as a scaffold for chondrocyte transplantation. 相似文献
17.
Elia M. Taricco G. Viterbo E. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1999,45(6):2020-2029
Maximization of the energy transfer ratio for time-limited signals over linear channels is considered. The case of linear channels with rational transfer function is addressed and a general procedure for the analytic solution of the maximization problem is outlined. The maximum energy transfer ratio over a fixed time interval is evaluated in some cases of interest. Two performance metrics-the energy transfer ratio and the energy intersymbol interference (ISI) ratio-are evaluated for optimal signals and compared to those of commonly used rectangular and sinusoidal pulses in order to determine the achievable gain 相似文献
18.
In this work we consider algorithms based on the singular value decomposition (SVD) to approximate Lyapunov and exponential dichotomy spectra of dynamical systems. We review existing contributions, and propose new algorithms of the continuous SVD method. We present implementation details for the continuous SVD method, and illustrate on several examples the behavior of continuous (and also discrete) SVD method. This paper is the companion paper of [L. Dieci, C. Elia, The singular value decomposition to approximate spectra of dynamical systems. Theoretical aspects, J. Diff. Equat., in press]. 相似文献
19.
K. Butalag L. Maruccio M. D’Elia 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(10):2353-2357
Obsidian tools from archaeological sites in Turkey and Southern Italy, 14C-AMS dated to the Neolithic were submitted to IBA analyses at CEDAD, University of Salento, Italy. PIXE and PIGE quantitative analysis of major and trace elements allowed the separation of the samples in different compositional groups corresponding to different sources of obsidian, identified on the basis of published data. 相似文献
20.
Anna Bonasia Giulia Conversa Corrado Lazzizera Giuseppe Gambacorta Antonio Elia 《Journal of the science of food and agriculture》2010,90(15):2689-2693
BACKGROUND: Three new artichoke seed‐propagated hybrids (Tempo, Opal and Madrigal) were compared with two standard cultivated varietal types [Catanese and Violet du Provence (VP)] in terms of head morphology, processing performance, nutritional or technological qualitative traits, in order to define their best use. RESULTS: Compared to the other genotypes, Opal and Madrigal had more rounded, heavier, larger heads, higher processing yield (>400 g of heart kg?1 raw head) and lower total phenol (TP) content (2.4 g of gallic acid equivalents kg?1 FW). VP gave a higher processing yield than Catanese and showed the highest TP content (6.5 g kg?1 FW). Tempo hearts were more similar to those of VP in biometrical and chemical terms (P, Na, K, Ca); they had the highest dry matter content (163 g kg?1 FW) and the waste left after peeling had the highest TP content. CONCLUSIONS: Hybrid artichokes, especially Opal and Madrigal, appear more suitable for the processing industry and also for fresh‐cut production due to their highest processing yield and lowest total phenol content. Because of its high total phenol content, Tempo waste represents a possible source of natural antioxidant in the pharmaceutical field and in the food industry (as a food additive). Copyright © 2010 Society of Chemical Industry 相似文献