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排序方式: 共有991条查询结果,搜索用时 15 毫秒
791.
Caballero Pablo Ortiz Guadalupe Garcia-de-Prado Alfonso Boubeta-Puig Juan 《Multimedia Tools and Applications》2021,80(14):21101-21133
Multimedia Tools and Applications - In recent years, the evolution of smartphones and their software applications has grown exponentially; together with the advance of the Internet of Things and... 相似文献
792.
Alfonso Díez-Minguela Rafael González-Val Julio Martinez-Galarraga M. Teresa Sanchis Daniel A. Tirado 《Papers in Regional Science》2020,99(3):479-508
This paper analyses the long-term relationship between regional inequality and economic development. Our data set includes information on national and regional per capita GDP for four countries: France, Italy, Portugal and Spain, compiled on a decadal basis for the period 1860–2010. Using parametric and semiparametric regressions, our results confirm the rise and fall of regional inequalities over time although in recent decades they are on the rise again. Finally, we identify structural change as being a significant transmission mechanism of the inverted-U relationship. The arrival of technological shocks, beginning during the onset of industrialization, and the transition from agrarian to industrial economies, would explain this result. 相似文献
793.
794.
Sara Stelitano Victor Lazzaroli Giuseppe Conte Valentino Pingitore Alfonso Policicchio Raffaele Giuseppe Agostino 《应用聚合物科学杂志》2020,137(48):49587
Carbon capture and storage (CCS) in conjunction with an increasing use of renewables provides a clean pathway to sustainable development and climate change mitigation. In selecting a low temperature CCS adsorbent, parameters such as selectivity, regeneration energy, and economicity play a crucial role. Poly(L-lactide) (PLA) is one of the most promising materials in science and engineering, not only because it is a green polymer progressively replacing petrobased plastics, but also for its carbon dioxide (CO2)-philic nature that makes it a suitable candidate for greenhouse gas capture and climate change mitigation. Literature data point to PLA as a valid CCS candidate, although no direct gaseous CO2 adsorption investigation or with mild preparation/regenerative energy was reported. In the present experimental work, a deeper investigation of the adsorption/desorption properties of PLA in presence of gaseous CO2 at room temperature was undertaken by means of a home-made Sievert-type apparatus. The effects of pressure (0–15 bar), morphology (commercial pellets, powder, and flakes), and regenerative energy (303 and 333 K) were investigated. PLA samples were also characterized by helium picnometry to obtain skeletal density and by XRD and SEM to obtain morphological and structural information. Results show that PLA represents a valid and ecological alternative among the materials for the capture of CO2. The PLA absorption capacity reaches 16 wt% at 15 bar and 303 K, and is closely linked to the thermal treatment, morphology, and crystalline structure of the material. 相似文献
795.
Marika Vellei Alfonso P. Ramallo-González David Coley Jeehang Lee Elizabeth Gabe-Thomas Tom Lovett 《Building Research & Information》2017,45(1-2):102-118
ABSTRACTAs the 2003 European heatwave demonstrated, overheating in homes can cause wide-scale fatalities. With temperatures and heatwave frequency predicted to increase due to climate change, such events can be expected to become more common. Thus, investigating the risk of overheating in buildings is key to understanding the scale of the problem and in designing solutions. Most work on this topic has been theoretical and based on lightweight dwellings that might be expected to overheat. By contrast, this study collects temperature and air quality data over two years for vulnerable and non-vulnerable UK homes where overheating would not be expected to be common. Overheating was found to occur, particularly and disproportionately in households with vulnerable occupants. As the summers in question were not extreme and contained no prolonged heatwaves, this is a significant and worrying finding. The vulnerable homes were also found to have worse indoor air quality. This suggests that some of the problem might be solved by enhancing indoor ventilation. The collected thermal comfort survey data were also validated against the European adaptive model. Results suggest that the model underestimates discomfort in warm conditions, having implications for both vulnerable and non-vulnerable homes. 相似文献
796.
Maria Giulia Fabbrini Damiano Cirri Dr. Alessandro Pratesi Dr. Lorenzo Ciofi Dr. Tiziano Marzo Dr. Annalisa Guerri Dr. Silvia Nistri Alfonso Dell'Accio Tania Gamberi Dr. Mirko Severi Prof. Andrea Bencini Prof. Luigi Messori 《ChemMedChem》2019,14(1):182-188
The silver(I) N-heterocyclic carbene (NHC) complex bis(1-(anthracen-9-ylmethyl)-3-ethylimidazol-2-ylidene) silver chloride ([Ag(EIA)2]Cl), bearing two anthracenyl fluorescent probes, has been synthesized and characterized. [Ag(EIA)2]Cl is stable in organic solvents and under physiological conditions, and shows potent cytotoxic effects in vitro toward human SH-SY5Y neuroblastoma cells. The interactions of [Ag(EIA)2]Cl with a few model biological targets have been studied as well as its ability to be internalized in cells. The in vitro anticancer activity is apparently related to the level of drug internalization. Notably, [Ag(EIA)2]Cl does not react with a few model proteins, but is capable of binding the C-terminal dodecapeptide of thioredoxin reductase hTrxR(488–499) and to strongly inhibit the activity of this enzyme. Binding occurs through an unconventional process leading to covalent binding of one or two carbene ligands to the C-terminal dodecapeptide with concomitant release of the silver cation. To the best of our knowledge, this mode of interaction is reported here for the first time for Ag(NHC)2 complexes. 相似文献
797.
César Muñoz-López Claude St Thomas Luis Alfonso García-Cerda Claudia Rivera-Vallejo Enrique Jiménez-Regalado 《应用聚合物科学杂志》2021,138(43):51270
The impact of additives on the rheological behavior of four associating water-soluble multiblock polyelectrolytes previously synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization was described. These polyelectrolytes contained different number of blocks ranged from 1 to 7 divided into hydrophilic and hydrophobic. The rheological analyses of polymers were performed at 25°C at a given concentration (0.1–15 wt%) in the presence of sodium chloride (NaCl) 0.1–0.5 M, sodium dodecyl sulfate (SDS) 2–10 mM or a mixture of both. Data demonstrated an increase in the viscosity of macroRAFT (ɳ = 0.002–9 Pa·s) and triblock copolymer-TBC (ɳ = 0.003–0.04 Pa·s) versus the concentration of NaCl. Meanwhile, the viscosity of penta and heptablock copolymer exhibited a diminution whatever the (NaCl) used. Results from the rheological analyses of the associative polyelectrolytes at different (SDS) revealed that the viscosity of macroRAFT and triblock copolymer was kept constant in spite of the increment of the (SDS) while the viscosity of PBC and HBC displayed a pronounced diminution at the lower (SDS). Finally, the results from the rheological analyses of these polyelectrolytes versus a mixture of NaCl-SDS showed a diminution in the viscosity of these solutions at any concentration of additives. 相似文献
798.
799.
Barrientos Eva Pelayo Fernández Noriega Álvaro Lamela María Jesús Fernández-Canteli Alfonso Tanaka Eiji 《Mechanics of Time-Dependent Materials》2019,23(2):193-206
Mechanics of Time-Dependent Materials - Viscoelastic models based on Prony series are usually used due to easy implementation in finite element analysis codes. The experimental data are fitted to a... 相似文献
800.