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81.
Michele Scaraggi 《Tribology Letters》2014,53(1):127-143
We present the calculation results of optimal texture geometries which maximize the supported load for a three-dimensional thrust bearing pad. By making use of the recently developed mean field theory of texture hydrodynamics, we develop an efficient multigrid optimization procedure based on the sequential genetic and conjugate gradient optimization. We show that our model allows to determine optimal solutions based on a two-scale hierarchy of structures, and the existence of particularly effective optimal geometries is presented and discussed. 相似文献
82.
Federico Bertasi Keti Vezzù Guinevere A. Giffin Tetiana Nosach Paul Sideris Steve Greenbaum Michele Vittadello Vito Di Noto 《International Journal of Hydrogen Energy》2014
Molecular relaxation and polarization phenomena of twelve single-ion-conducting nanocomposite polymer electrolytes (nCPEs) are studied using Broadband Electrical Spectroscopy (BES). The electrolytes are obtained by combining PEG400 oligomers with increasing amounts of anionic nanofiller comprised of fluorinated-TiO2 associated with Li+ cations (LiFT®), resulting in [PEG400/(LiFT)y] systems with 0 ≤ y ≤ 26.4. This new class of [PEG400/(LiFT)y] electrolytes allows us to achieve a significant single-ion conductivity (1.1·10−5 S cm−1 at 30 °C for nLi/nO = 0.113) without the addition of lithium salts. To the best of our knowledge, this is the highest conductivity value reported for this class of electrolytes. This study, in conjunction with the results reported in Part 1, leads us to hypothesize a conduction mechanism in terms of two types of long-range charge-transfer processes. The first charge-transfer occurs at the interface between the filler nanoparticles and filler-PEG domains, while the second occurs through the PEG400 matrix with the assistance of polymer segmental motion. The measured Li+ transference numbers confirm that the studied materials are single-ion conductors. 相似文献
83.
This paper investigates the within-country location choices of a large sample of foreign and domestic firms in 19 Sub-Saharan African countries. We show that foreign firms are more likely to locate in core regions compared to domestic ones but generate significantly more jobs per productive unit in the periphery. We find some evidence that foreign firms generate relatively better jobs in peripheral areas: more skill intensive and better paid. These results highlight a fundamental role that FDI in peripheral areas might play in rebalancing the spatial distribution of economic opportunities in developing countries where highly congested megacities exercise a strong centripetal force. 相似文献
84.
Soil sealing footprint as an indicator of dispersed urban growth: a multivariate statistics approach
The present study introduces a set of indicators derived from high-resolution land-use maps with the aim to illustrate the spatial distribution, intensity, and diversity of sealed soils in a Mediterranean region (Rome, Italy) shifting from a mono-centric spatial organization toward a dispersed urban agglomeration. A multivariate approach provides a comprehensive assessment of Rome ‘sealing footprint’, classifying local districts according to different imperviousness profiles. Results illustrate the rearrangement of the land-use structure determined by suburbanization with higher soil consumption and lower land-use efficiency. The approach is considered a promising tool to inform policies for a spatially balanced and land-saving urban development. 相似文献
85.
Dr. Francesca Ferlenghi Dr. Michele Mari Prof. Gabriella Gobbi Dr. Gian Marco Elisi Prof. Marco Mor Prof. Silvia Rivara Prof. Federica Vacondio Dr. Silvia Bartolucci Prof. Annalida Bedini Dr. Fabiola Fanini Prof. Gilberto Spadoni 《ChemMedChem》2021,16(19):3071-3082
The MT2-selective melatonin receptor ligand UCM765 (N-(2-((3-methoxyphenyl)(phenyl)amino)ethyl)acetamide), showed interesting sleep inducing, analgesic and anxiolytic properties in rodents, but suffers from low water solubility and modest metabolic stability. To overcome these limitations, different strategies were investigated, including modification of metabolically liable sites, introduction of hydrophilic substituents and design of more basic derivatives. Thermodynamic solubility, microsomal stability and lipophilicity of new compounds were experimentally evaluated, together with their MT1 and MT2 binding affinities. Introduction of a m-hydroxymethyl substituent on the phenyl ring of UCM765 and replacement of the replacement of the N,N-diphenyl-amino scaffold with a N-methyl-N-phenyl-amino one led to highly soluble compounds with good microsomal stability and receptor binding affinity. Docking studies into the receptor crystal structure provided a rationale for their binding affinity. Pharmacokinetic characterization in rats highlighted higher plasma concentrations for the N-methyl-N-phenyl-amino derivative, consistent with its improved microsomal stability and makes this compound worthy of consideration for further pharmacological investigation. 相似文献
86.
Silvio Barbarelli Mario Amelio Teresa Castiglione Gaetano Florio Nino Michele Scornaienchi 《国际能源研究杂志》2021,45(1):661-690
The aim of this paper is to illustrate the design of a new wave energy converter, composed of a point absorber and a hydraulic system (power take off) and sized for recovering energy in calm seas from waves near the shore. The point absorber is consisting of a rectangular shaped buoy integrating a piston pump. The set buoy‐pump oscillates under the waves action and moves natural water in a closed circuit hydraulic system (power take off) composed of a piping connecting the piston pump itself, a pressurized reservoir, a hydraulic turbine and a discharge tank. The methodology adopted for designing the main constituents involves a 1D mathematical model, settled for understanding the motion of the buoy under the hypothesis of regular waves and fully developed sea, and a sizing procedure applied for the design of all the components of the hydraulic system. The project related to the Calabrian site of Cetraro (Mediterranean Sea—south Italy) led to designing a system with a 4 m large buoy, associated with a small 13 cm diameter micro Pelton turbine, so that more than 22 000 kWh could be recovered in a year. 相似文献
87.
Cristina Jansen-Alves Karina F. Fernandes Michele M. Crizel-Cardozo Fernanda D. Krumreich Caroline D. Borges Rui C. Zambiazi 《Food and Bioprocess Technology》2018,11(7):1422-1436
Propolis presents several health benefits due to the presence of bioactive compounds, mainly phenolic compounds; however, its application in food is limited due to undesirable odor and low water solubility. The bioactive compounds are usually susceptible to degradation by exposure to light, heat, or oxygen or by interaction with other compounds, which may limit its biological activity. The study aimed the propolis extract microencapsulation using rice, pea, soybean, and ovoalbumin proteins as wall material by spray drying and to analyze their in vitro digestion. The propolis extract presented a high concentration of apigenin. Encapsulation efficiency was greater than 70%, and it was maintained the antioxidant activity of propolis (88% inhibition of DPPH for propolis extract and >?73% for the microparticles). The DSC, ATR-FTIR, and X-ray diffraction techniques confirmed the encapsulation. The microparticles showed different shapes, sizes, and physical characteristics. The microparticles encapsulated with pea protein could be used in formulations of Minas Frescal cheese due to the controlled released, whereas the other microparticles could be used in pudding formulations. 相似文献
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