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131.
Moschini  Ugo  Fenialdi  Elena  Daraio  Cinzia  Ruocco  Giancarlo  Molinari  Elisa 《Scientometrics》2020,125(2):1145-1158
Scientometrics - In this paper, we compare the distribution of Elsevier Scopus subject areas of authors’ documents, their bibliographical references and their citing documents. We compute the...  相似文献   
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At the few‐atom‐thick limit, transition‐metal dichalcogenides (TMDs) exhibit strongly interconnected structural and optoelectronic properties. The possibility to tailor the latter by controlling the former is expected to have a great impact on applied and fundamental research. As shown here, proton irradiation deeply affects the surface morphology of bulk TMD crystals. Protons penetrate the top layer, resulting in the production and progressive accumulation of molecular hydrogen in the first interlayer region. This leads to the blistering of one‐monolayer thick domes, which stud the crystal surface and locally turn the dark bulk material into an efficient light emitter. The domes are stable (>2‐year lifetime) and robust, and host strong, complex strain fields. Lithographic techniques provide a means to engineer the formation process so that the domes can be produced with well‐ordered positions and sizes tunable from the nanometer to the micrometer scale, with important prospects for so far unattainable applications.  相似文献   
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In this study, the combined effects of hydrological and chemical stressors on benthic macroinvertebrates were evaluated in order to explore the response of the biological community to multiple stressors. The Adige River, located in the south‐eastern Alps, was selected as a case study because representative of the situation of a large river in which the variety of stressors present in the Alpine region act simultaneously. As expected, streamflow showed a seasonal pattern, with high flows in the spring–summer period; however, locally, the natural hydrological regime was altered by the presence of hydropower systems, which chiefly affected low flows. Multivariate analysis showed seasonal and spatial patterns in both chemical and hydrological parameters with a clear gradient in the concentration of nitrate, personal care, and pharmaceutical products moving from headwaters to the main stem of the river. The macroinvertebrate community composition was significantly different in summer and winter and between up and downstream sites. Streamflow alteration chiefly due to water use by hydropower affected community composition but not richness or diversity. Gammarus sp., Hirudinea, and Psychomyia sp., were positively correlated with flow variability, increasing their densities in the sites with higher streamflow variability because of hydropeaking. The results obtained in this study show that the composition of the macroinvertebrate community responded to seasonality and to changes in the main stressors along the river and highlights the importance of the spatial and temporal variability of stressors in this Alpine river. Taking into account, this variability will help the decision‐making process for improving basin management.  相似文献   
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Inspired by the recent success of buckling-induced reconfigurable structures, a new class of deployable systems that harness buckling of curved beams upon a rotational input is proposed. First, experimental and numerical methods are combined to investigate the influence of the beam's geometric parameters on its non-linear response. Then, it is shown that a wide range of deployable architectures can be realized by combining curved beams. Finally, the proposed principles are used to build deployable furniture such as tables and lamp shades that are flat/compact for transportation and storage, require simple or no assembly, and can be expanded by applying a simple rotational input.  相似文献   
138.
Pieri  Luca  Serino  Silvia  Cipresso  Pietro  Mancuso  Valentina  Riva  Giuseppe  Pedroli  Elisa 《Virtual Reality》2022,26(2):639-648
Virtual Reality - One important feature of a neuropsychological test is its ecological validity, which defines how much patients’ test scores are linked to real-life functioning. However,...  相似文献   
139.
Software assurance tools – tools that scan the source or binary code of a program to find weaknesses – are the first line of defense in assessing the security of a software project. Even though there are a plethora of such tools available, with multiple tools for almost every programming language, adoption of these tools is spotty at best. And even though different tools have distinct abilities to find different kinds of weaknesses, the use of multiple tools is even less common. And when the tools are used (or attempted to be used), they are often used in ways that reduce their effectiveness. We present a step‐by‐step discussion of how to use a software assurance tool, describing the challenges that can occur in this process. We also present quantitative evidence about the effects that can occur when assurance tools are applied in a simplistic or naive way. We base this presentation on our direct experiences with using a wide variety of assurance tools. We then present the US Department of Homeland Security funded Software Assurance Marketplace (SWAMP), an open facility where users can upload their software to have it automatically and continually assessed by a variety of tools. The goal of the SWAMP is to simplify the task of the programmer in using assurance tools, thereby removing many of the obstacles to their adoption. Copyright © 2016 The Authors. Software: Practice and Experience Published by John Wiley & Sons, Ltd.  相似文献   
140.
The chemical modification of isotactic polypropylene was performed by the free‐radical‐promoted grafting of 1,1,1‐trimethylolpropane trimethacrylate (TMPTMA) in the presence of dicumyl peroxide (DCP) as the initiator. The reaction was carried out both in a batch internal mixer and in a corotating twin‐screw extruder; the effects of the peroxide and monomer concentrations on the extent of modification in terms of the grafting efficiency and polymer chain structure variations were investigated. The modified samples were characterized with Fourier transform infrared to determine the structure of the grafted groups and the degree of functionalization, with gel permeation chromatography and the melt flow index to evaluate changes in the molecular weight, and with differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical thermal analysis to measure the final thermal properties. In addition, solvent extraction with xylene was performed to highlight the presence of gel and its extent. The structure of the grafted groups was determined, and the number of grafted groups was quantitatively evaluated. The degree of functionalization increased with an increasing TMPTMA/DCP molar ratio. Thermal analysis results hinted at the presence of grafted chains with an increased percentage of TMPTMA. Although degradation reactions predominated at high amounts of peroxide, grafting and branching processes became competitive at high levels of TMPTMA. The balance between competing β‐scission and grafting/branching reactions could be adjusted on the basis of feed conditions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 950–958, 2007  相似文献   
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