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131.
Marco Masi Seyed Arash Moeini Angela Boari Alessio Cimmino Maurizio Vurro 《Natural product research》2018,32(13):1611-1615
Cavoxin is a tetrasubstituted phytotoxic chalcone and cavoxone is the corresponding chroman-4-one, both produced in vitro by Phoma cava, a fungus isolated from chestnut. Cavoxin showed biofungicide potential against fungal species responsible for food moulding. Therefore, cavoxin has potential to be incorporated into biopolymer to generate ‘intelligent food packaging’. To reach this objective, large-scale production of cavoxin by P. cava fermentation needs to be optimized. A rapid and efficient method for cavoxin analysis, as well as of cavoxone, in the fungal culture filtrates and the corresponding organic extracts is the first experimental step. Thus, a HPLC method was developed and applied to quantify cavoxin and cavoxone production in two different fungal culture conditions. The analysis proved that cavoxin production in stirred culture filtrates is significantly higher than in static ones. 相似文献
132.
Alessio Figalli Ludovic Rifford Cédric Villani 《Calculus of Variations and Partial Differential Equations》2010,39(3-4):307-332
We investigate the properties of the Ma–Trudinger–Wang nonlocal curvature tensor in the case of surfaces. In particular, we prove that a strict form of the Ma–Trudinger– Wang condition is stable under C 4 perturbation if the nonfocal domains are uniformly convex; and we present new examples of positively curved surfaces which do not satisfy the Ma–Trudinger–Wang condition. As a corollary of our results, optimal transport maps on a “sufficiently flat” ellipsoid are in general nonsmooth. 相似文献
133.
Michele Mangiameli Alessio Candiano Gabriele Fargione Andrea Gennaro Giuseppe Mussumeci 《Mathematical Methods in the Applied Sciences》2020,43(13):7640-7646
We propose a new GIS-based procedure to retrieve archaeological elements using satellite remote sensing. The processing of multispectral satellite images consists in a preprocessing phase using the pansharpening technique to improve the spatial quality and in the exploitation of linear equations of the initial spectral bands with the aim of generating accurate and precise raster data that can be used as input for an object classification. The proposed methodology has been tested in an archaeological area located on the north-west flank of Etna volcano (Sicily, Italy). 相似文献
134.
Boege Tobias D’Alì Alessio Kahle Thomas Sturmfels Bernd 《Foundations of Computational Mathematics》2019,19(4):775-812
Foundations of Computational Mathematics - A gaussoid is a combinatorial structure that encodes independence in probability and statistics, just like matroids encode independence in linear algebra.... 相似文献
135.
Francesca Leonelli Luisa Maria Migneco Alessio Valletta Rinaldo Marini Bettolo 《Molecules (Basel, Switzerland)》2021,26(9)
The scientific activity carried out over forty-five years on stemodane diterpenes and diterpenoids structure elucidation, biogenesis, biosynthesis, biological activity and biotransformations was reviewed. 相似文献
136.
137.
In this work, we show how to obtain for non-compact manifolds the results that have already been done for Monge Transport
Problem for costs coming from Tonelli Lagrangians on compact manifolds. In particular, the already known results for a cost
of the type d
r
, r > 1, where d is the Riemannian distance of a complete Riemannian manifold, hold without any curvature restriction. 相似文献
138.
Ombretta Largiuni Emiliano Castellano Alessio Migliori Rita Traversi Giovanni Piccardi Roberto Udisti 《International journal of environmental analytical chemistry》2013,93(6-7):537-549
Formaldehyde concentrations were determined in over 1800 snow samples (snowpit, firn cores and superficial snow) from Antarctica by a sensitive spectrofluorimetric Flow Injection Analysis method. The method performances (detection limit: 55?ng/L; reproducibility: 2.5% at 1?µg/L level; linear range: 0.1–3000?µg/L) allowed a reliable determination of formaldehyde content in all the collected samples. The range of determined concentrations was 0–70?µg/L with a mean concentration of 7.7?µg/L and a median concentration of 5.8?µg/L. The formaldehyde background level was estimated at a few micrograms per liter in coastal and plateau areas of Northern Victoria Land. In some stations the background values are modulated by HCHO deposition events recurring over relatively large time periods. 相似文献
139.
Influence of the interface material layers and semiconductor energetic disorder on the open circuit voltage in polymer solar cells 下载免费PDF全文
Martina Dianetti Luigi Salamandra Francesco Santoni Alessio Gagliardi Matthias Auf der Maur Francesca Brunetti Andrea Reale Thomas M. Brown Aldo Di Carlo 《Journal of Polymer Science.Polymer Physics》2015,53(10):690-699
Material layers at electrode/semiconductor interfaces are fundamental for the photovoltaic properties of polymer solar cells. The relationship between open‐circuit voltage ( VOC ) and the work function ( φ ) of these interface layers is still a matter of debate. Simulations, together with experiments on over more than 20 cell architectures based on P3HT:PC60BM, enabled us to analyze the physical dependence of VOC on φ . In particular, when the work function of the contacts is well inside the gap we observe that performance depends strongly on even small variations of φ . On the other hand, when it approaches the energy levels of the semiconducting polymers, device operation becomes the most efficient and less sensitive to variations in φ . Furthermore, by varying the Gaussian density of states (DOS) of the active blend we were able to show that VOC performance depends significantly also on the DOS. Our study based on the simultaneous variation of transport layers represents a promising method to optimize the design and performance of polymer solar cells. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 690–699 相似文献
140.
Trentin Priscila O. Perardt Mariana Medeiros-Junior Ronaldo A. 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6631-6642
Journal of Thermal Analysis and Calorimetry - The search for new materials to replace Portland cement (PC) has increased due to the high release of carbon dioxide (CO2) and the exploration of raw... 相似文献