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排序方式: 共有273条查询结果,搜索用时 15 毫秒
171.
Venture capital has proven to be an essential resource for economic growth, especially in some technological clusters. The focus is on the way the venture capitalist makes the investment decision and the portfolio selection. The aim of this paper is to formulate the venture capital investment problem through the Goal Programming model where the Financial Decision-Maker’s preferences will be explicitly incorporated through the concept of satisfaction functions. The proposed model will be illustrated by using data from an Italian venture capital fund. 相似文献
172.
Chiappe C Pomelli CS Bardi U Caporali S 《Physical chemistry chemical physics : PCCP》2012,14(15):5045-5051
Interfaces and surfaces are the regions where important events happen: catalysis, molecular recognition, charge transfer, polymerization, and many other critical processes take place at the boundary between one medium and another. In this article we discuss the interface (liquid/air) properties of ionic liquids (ILs) containing dissolved metal ions with the aim to show the possibility to use metal salts to transform ILs and their surfaces into engineered liquid supports to apply in material sciences, separation procedures or to use as optical devices. 相似文献
173.
The goal of this study is to inform those potentially interested (researchers, farmers, industry and public bodies) in the medicinal and aromatic properties, and profitability of Perilla frutescens (L.) Britton (Lamiaceae). Perilla, a medicinal and edible plant of Asian origin, was recently introduced to the Piedmont Region in the north-west of Italy. P. frutescens is commonly known for its anti-allergic, anti-tumor, and anti-oxidant properties. It is also widely used as human food. We collected a variety of data on Perilla crops in the Piedmont Region, including: agricultural practices, crop profitability, and its value as a bee plant. Our results suggest that ease of cultivation, approximate break-even economics, medicinal claims, and value for bees all contribute to make Perilla of economic interest in Italy. 相似文献
174.
Maxia A Sanna C Frau MA Piras A Karchuli MS Kasture V 《Natural product communications》2011,6(10):1543-1544
The topical anti-inflammatory activity of essential oil of Pistacia lentiscus L. was studied using carrageenan induced rat paw edema and cotton pellet induced granuloma. The effect on serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in rats inserted with cotton pellet was also investigated. On topical application, the oil exhibited a significant decrease in paw edema. The oil also inhibited cotton pellet-induced granuloma, and reduced serum TNF-alpha and IL-6. It can be concluded that the essential oil of Pistacia lentiscus reduces leukocyte migration to the damaged tissue and exhibits anti-inflammatory activity. 相似文献
175.
Guzzi C Angulo J Doro F Reina JJ Thépaut M Fieschi F Bernardi A Rojo J Nieto PM 《Organic & biomolecular chemistry》2011,9(22):7705-7712
In this work, we have studied in detail the binding of two α-fucosylamide-based mimics of Lewis(X) to DC-SIGN ECD (ECD = extracellular domain) using STD NMR and docking. We have concluded that the binding mode occurs mainly through the fucose moiety, in the same way as Lewis(X). Similarly to other mimics containing mannose or fucose previously studied, we have shown that both compounds bind to DC-SIGN ECD in a multimodal fashion. In this case, the main contact is the interaction of two hydroxyl groups one equatorial and the other one axial (O3 and O4) of the fucose with the Ca(2+) as Lewis(X) and similarly to mannose-containing mimics (in this case the interacting groups are both in the equatorial position). Finally, we have measured the K(D) of one mimic that was 0.4 mM. Competitive STD NMR experiments indicate that the aromatic moiety provides additional binding contacts that increase the affinity. 相似文献
176.
The roots of Mirabilis jalapa are used traditionally in allergic skin disorders and asthma. The effect of an ethanol:acetone (1:1) extract of the roots of M. jalapa was studied for antihistaminic activity using a guinea pig tracheal chain preparation and clonidine-induced mast cell granulation in mice. Its antiallergic activity was evaluated using milk-induced eosinophilia and albumin-induced paw oedema in mice. The extract (0.5 mL of 100 mg mL(-1)) inhibited histamine-induced guinea pig tracheal chain contractions non-competitively. The extract (100 or 200 mg kg(-1) i.p.) inhibited milk-induced eosinophilia, albumin-induced paw oedema and protected mast cells against clonidine-induced granulation. The study justified the folkloric use of M. jalapa in the treatment of allergic diseases and asthma. 相似文献
177.
A study of the reaction of thioanisole with singlet oxygen in different ionic liquid-acetonitrile binary mixtures has shown that ILs are able to accelerate the thioanisole sulfoxidation when used as additives. With imidazolium ILs, the maximum efficiency is reached at x(IL) ~ 0.1-0.2, whereas for the pyrrolidinium IL a plateau is reached. These results are discussed in terms of the ILs' tendency to form ionic aggregates and of differences in sulfoxidation reaction mechanism. 相似文献
178.
Maria Vittoria Ciampolillo Annamaria Zaltron Marco Bazzan Nicola Argiolas Cinzia Sada Sabrina Mignoni Marc Fontana 《Applied Physics A: Materials Science & Processing》2011,104(1):453-460
Thermal diffusion from thin film is one of the most widespread approaches to prepare iron doped regions in lithium niobate
with limited size for photorefractive applications. In this work, we investigate the doping process with the aim of determining
the best process conditions giving a doped region with the characteristics required for photorefractive applications. Six
samples were prepared by changing the atmosphere employed in the diffusion treatment in order to obtain different combination
of diffusion profiles and reduction degrees and also to check the effect of employing a wet atmosphere. The compositional,
optical, and structural properties are then extensively characterized by combining Secondary ion Mass Spectrometry, UV, visible
and IR spectrophotometry, High Resolution X-Rays Diffraction, and Micro-Raman Spectroscopy. Moreover, the sample topography
was checked by Atomic Force Microscopy. An analysis of all our data shows that the best results are obtained performing a
double step process, i.e. diffusion in oxidizing atmosphere and subsequent reduction at lower temperature in an hydrogen-containing
atmosphere. 相似文献
179.
180.
Templateless synthesis of polypyrrole nanowires by non-static solution-surface electropolymerization
Antonio Turco Elisabetta Mazzotta Cinzia Di Franco Maria Vittoria Santacroce Gaetano Scamarcio Anna Grazia Monteduro Elisabetta Primiceri Cosimino Malitesta 《Journal of Solid State Electrochemistry》2016,20(8):2143-2151
Polypyrrole nanowires (PPy-NWs) are synthesized by a novel templateless approach based on non-static solution-surface (NSSS) electropolymerization. The mechanism responsible for PPy-NW formation is the simultaneous oxidation of pyrrole and water, with concomitant formation of hydroxyl radicals and dioxygen nanobubbles. In particular, a localized PPy-NW deposition at the solution-air interface is enabled by solution-surface electropolymerization due to the surface excess of the monomer at the interface favored by the large surface tension of the solvent. In the proposed approach, solution-surface electropolymerization is performed in non-static conditions (NSSS), as the solution-air interface is shifted by flowing the electrolyte solution over the electrode surface. This allows a PPy-NW homogeneous deposition on whatever large area electrode to be rapidly achieved. Parameters influencing the morphology of PPy-NWs are studied, particularly focusing on flow rate, pH of the electrolyte solution, and electropolymerization time. The growth process of PPy-NWs is examined and the way of tuning their resulting morphology is discussed. Morphological investigation by scanning electron microscopy and chemical/electrochemical characterization of PPy-NWs by X-ray photoelectron spectroscopy and cyclic voltammetry, respectively, further support the proposed nanowire formation mechanism. Nanowires with diameter in the range of 40–300 nm are obtained, and the possibility of depositing differently sized nanowires with a predetermined spatial distribution on the same substrate is also demonstrated. 相似文献