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Nicola Curci Andrea Strazzulli Roberta Iacono Federica De Lise Luisa Maurelli Mauro Di Fenza Beatrice Cobucci-Ponzano Marco Moracci 《International journal of molecular sciences》2021,22(7)
In the field of biocatalysis and the development of a bio-based economy, hemicellulases have attracted great interest for various applications in industrial processes. However, the study of the catalytic activity of the lignocellulose-degrading enzymes needs to be improved to achieve the efficient hydrolysis of plant biomasses. In this framework, hemicellulases from hyperthermophilic archaea show interesting features as biocatalysts and provide many advantages in industrial applications thanks to their stability in the harsh conditions encountered during the pretreatment process. However, the hemicellulases from archaea are less studied compared to their bacterial counterpart, and the activity of most of them has been barely tested on natural substrates. Here, we investigated the hydrolysis of xyloglucan oligosaccharides from two different plants by using, both synergistically and individually, three glycoside hydrolases from Saccharolobus solfataricus: a GH1 β-gluco-/β-galactosidase, a α-fucosidase belonging to GH29, and a α-xylosidase from GH31. The results showed that the three enzymes were able to release monosaccharides from xyloglucan oligosaccharides after incubation at 65 °C. The concerted actions of β-gluco-/β-galactosidase and the α-xylosidase on both xyloglucan oligosaccharides have been observed, while the α-fucosidase was capable of releasing all α-linked fucose units from xyloglucan from apple pomace, representing the first GH29 enzyme belonging to subfamily A that is active on xyloglucan. 相似文献
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Cristina Marullo Alberto Di Minin Chiara De Marco Andrea Piccaluga 《Creativity & Innovation Management》2020,29(2):209-223
Open innovation (OI) projects are increasingly adopted by small‐ and medium‐sized enterprises (SMEs). Yet, undertaking OI is not only a source of opportunities for SMEs as it can, at the same time, present risks. How SMEs manage the balance between the potential benefits and the emerging challenges of OI is still an overlooked topic in the literature. Using evidence gathered through multiple case studies and drawing upon the relational view of the firm, we explore how and why value creation opportunities and different managerial challenges emerge for SMEs pursuing OI projects. We analyze different stages of OI projects in several different contexts of their implementation. Our analysis sheds light on the different nature and dynamics of knowledge involved within OI projects as important boundary conditions affecting successful search paths, learning processes, and the development of appropriability mechanisms. By offering a contextualized view of OI in SMEs, this study also provides insights to business managers on the situational opportunities and constraints of OI, including managerial suggestions on actions to manage tensions within differing OI projects. 相似文献
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Alicia Torres Beatriz Fuentes Karina E. Rodríguez Andrea Brito Laura Díaz 《Journal of the American Oil Chemists' Society》2020,97(6):651-661
The increasing importance of sustainability in energy production has led to a global commitment to the use of fuels derived from renewable biological sources, such as biodiesel produced from plant crops or biomass residues, that do not compete with human food for their production. For a biofuel to be considered biodiesel, it must satisfy the specifications described in the UNE 14214, with the UNE-EN 14103 referring to the determination of fatty acid methyl ester content. This standard applies gas chromatography as an analytical technique. Gas chromatography is a widely used technique in the analysis of methyl ester although it has a number of drawbacks such as: long analysis times, a high consumption of high-quality gases and internal standards, does not allow the analysis of different compounds with the same column, etc. From an industrial production point of view, is necessary to know the fatty acid methyl ester content in biodiesel samples quickly. This paper studies the development of an analytical method using Fourier transform infrared spectroscopy (FTIR) as alternative to gas chromatography (GC), since it is a simple, rapid, and precise analytical technique to quantify fatty acid methyl ester content in biofuel samples. 相似文献
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A rich research stream investigates the drivers and enablers of supplier sustainability practices, usually classified into suppliers’ monitoring and collaboration with suppliers. Differently from previous works analysing relationships between supplier sustainability practices and drivers or enablers, this research investigates how well-defined configurations of monitoring and collaboration can be characterised in terms of drivers and enablers. In this way, it intends to advance knowledge by identifying what drivers and enablers are important and distinctive for the different configurations of supplier sustainability practices. A first result is that moving from configurations of plants which less adopt supplier sustainability practices (i.e. non-adopters) to those which invest on monitoring and/or collaboration to a limited extent (i.e. partial adopters) up to the most advanced ones (i.e. full-adopters), the pressure due to cost reduction lessens its relative importance as a driver, while the pressure due to regulations remains essential. Other relevant results are that plant size acts as a barrier for non-adopters, and the alignment between the sustainability project and plant goals results determinant especially for full-adopters. This research also enriches the debate on the opportunity of differentiating between supplier monitoring and collaboration when investigating drivers/enablers, providing evidence of the risk of oversimplifications for some enablers/drivers. 相似文献
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Erdin Ibraim Jean-Francois Camenen Andrea Diambra Karolis Kairelis Laura Visockaite Nilo Cesar Consoli 《Geotextiles and Geomembranes》2018,46(4):497-510
This paper explores the aspects related to the energy consumption for the compaction of unreinforced and fibre reinforced samples fabricated in the laboratory. It is well known that, for a fixed soil density, the addition of fibres invariably results in an increased resistance to compaction. However, similar peak strength properties of a dense unreinforced sample can be obtained using looser granular soil matrices mixed with small quantities of fibres. Based on both experimental and discrete element modelling (DEM) procedures, this paper demonstrates that less compaction energy is required for building loose fibre reinforced sand samples than for denser unreinforced sand samples while both samples show similar peak strength properties. Beyond corroborating the macro-scale experimental observations, the result of the DEM analyses provides an insight into the local micro-scale mechanisms governing the fibre-grain interaction. These assessments focus on the evolution of the void ratio distribution, re-arrangement of soil particles, mobilisation of stresses in the fibres, and the evolution of the fibre orientation distribution during the stages of compaction. 相似文献