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131.
Margherita Durso Cristian Bettini Alberto Zanelli Massimo Gazzano M. Grazia Lobello Filippo De Angelis Viviana Biondo Denis Gentili Raffaella Capelli Massimiliano Cavallini Stefano Toffanin Michele Muccini Manuela Melucci 《Organic Electronics》2013,14(11):3089-3097
The synthesis of two new thieno(bis)imide (TBI, N) end functionalized oligothiophene semiconductors is reported. In particular, trimer (NT3N) and pentamer (NT5N) have been synthesized and characterized. Two different synthetic approaches for their preparation were tested and compared namely conventional Stille cross coupling and direct arylation reaction via C–H activation. Theoretical calculations, optical and electrochemical characterization allowed us to assess the role of the π-conjugation extent, i.e., of the oligomer size on the optoelectronic properties of these materials. In both TBI ended compounds, due to the strong localization of the LUMO orbital on the TBI unit, the LUMO energy is almost insensitive to the oligomer size, this being crucial for the fine-tailoring of the energy and the distribution of the frontier orbitals. Surprisingly, despite its short size and contrarily to comparable TBI-free analogues, NT3N shows electron charge transport with mobility up to μN = 10−4 cm2 V−1 s−1, while increasing the oligomer size to NT5N promotes ambipolar behavior and electroluminescence properties with mobility up to μN = 0.14 cm2 V−1 s−1 and to μP = 10−5 cm2 V−1 s−1. 相似文献
132.
Luigi Schibuola Massimiliano Scarpa Chiara Tambani 《能源与动力工程:英文版》2014,(6):1012-1020
The reliable assessment of the annual energy demand has become necessary in view of building energy performance certification. Accurate models must be used to simulate the behaviour of HVAC (heating, ventilation and air conditioning) components in real operation, usually characterized by a wide variation of building loads. In this context, this paper deals with the development and validation of an algorithm aimed at the assessment of part load performance of various kinds of controls for vapour compresion based heat pumps and chillers, in particular referring to on-off, inverter-driven and multi-stage vapour compression. The reliability of this algorithm in the calculation of seasonal performances is checked against monitoring of heat pumps and chillers operating under real conditions. 相似文献
133.
Lucio Boschetti Matteo Ottavian Pierantonio Facco Massimiliano Barolo Lorenzo Serva Stefania Balzan Enrico Novelli 《Meat science》2013
The use of near-infrared spectroscopy (NIRS) is proposed in this study for the characterization of the quality parameters of a smoked and dry-cured meat product known as Bauernspeck (originally from Northern Italy), as well as of some technological traits of the pork carcass used for its manufacturing. In particular, NIRS is shown to successfully estimate several key quality parameters (including water activity, moisture, dry matter, ash and protein content), suggesting its suitability for real time application in replacement of expensive and time consuming chemical analysis. Furthermore, a correlative approach based on canonical correlation analysis was used to investigate the spectral regions that are mostly correlated to the characteristics of interest. The identification of these regions, which can be linked to the absorbance of the main functional chemical groups, is intended to provide a better understanding of the chemical structure of the substrate under investigation. 相似文献
134.
Stefania Galdiero Annarita Falanga Marco Cantisani Mariateresa Vitiello Giancarlo Morelli Massimiliano Galdiero 《International journal of molecular sciences》2013,14(9):18758-18789
The interactions between peptides and lipids are of fundamental importance in the functioning of numerous membrane-mediated cellular processes including antimicrobial peptide action, hormone-receptor interactions, drug bioavailability across the blood-brain barrier and viral fusion processes. Moreover, a major goal of modern biotechnology is obtaining new potent pharmaceutical agents whose biological action is dependent on the binding of peptides to lipid-bilayers. Several issues need to be addressed such as secondary structure, orientation, oligomerization and localization inside the membrane. At the same time, the structural effects which the peptides cause on the lipid bilayer are important for the interactions and need to be elucidated. The structural characterization of membrane active peptides in membranes is a harsh experimental challenge. It is in fact accepted that no single experimental technique can give a complete structural picture of the interaction, but rather a combination of different techniques is necessary. 相似文献
135.
Douglas A. Orsini Kevin Rhoads Kyle McElhoney Erin Schick Danny Koehler Olga Hogrefe 《Aerosol science and technology》2013,47(5):343-356
A miniature cyclone was designed to gently capture fine aerosols into a continuous liquid flow. The geometry of the cyclone was designed so that the friction of the turning air swirls a 100 μl volume of water at the base of the cone, creating a standing liquid vortex which coats the inside deposition surface. The collection efficiency of the cyclone was characterized as a function of insoluble particle size, both in stand-alone operation and preceded by aerosol growth by water vapor condensation. The aerosol growth lowered the smallest collected particle size and created synonymous sample-into-substrate material conditions at the point of impact. The cyclone collection efficiencies were higher than 88% for the fluorescent polystyrene latex bead diameter sizes 50–3000 nm. The cyclone was further interfaced to a flow cytometer to detect airborne nucleic acid (as a virus test aerosol) in the cyclone sample flow. The flow cytometer, which is commonly used for single cell identification via fluorescence, was modified to accept a continuous sample flow (nominal 60 μl min?1) from the cyclone for real-time detection. A rod-shaped plant virus (Tobamovirus) and a protein-enveloped insect virus (Baculovirus) were aerosolized, collected by the cyclone, and stained inline using the nucleic acid dyes SYBR Green I, SYTO-9, and SYTO-24 (Molecular Probes, Inc.). In addition, an Environmental Scanning Electron Microscope (ESEM) was used to confirm the collection of single virus particles and qualitatively evaluate the degree to which the aerosolization and collection process affected the integrity of the virus. 相似文献
136.
Ehud Greenspan Ser Gi Hong Ki Bog Lee Lanfranco Monti Tsuyoshi Okawa Arnaud Susplugas Massimiliano Fratoni Lance Kim Sara Mattafirri Robert Petroski 《Progress in Nuclear Energy》2008,50(2-6):129-139
A number of approaches were explored for improving characteristics of the encapsulated nuclear heat source (ENHS) reactor and its fuel cycle, including: increasing the ENHS module power, power density and the specific power, making the core design insensitive to the actinides composition variation with number of fuel recycling and reducing the positive void coefficient of reactivity. Design innovations examined for power increase include intermediate heat exchanger (IHX) design optimization, riser diameter optimization, introducing a flow partition inside the riser, increasing the cooling time of the LWR discharged TRU, increasing the minor actinides' concentration in the loaded fuel and split-enrichment for power flattening. Another design innovation described utilizes a unique synergism between the use of MA and the design of reduced power ENHS cores.
Also described is a radically different ENHS reactor concept that has a solid core from which heat pipes transport the fission power to a coolant circulating around the reflector. Promising features of this design concept include enhanced decay heat removal capability; no positive void reactivity coefficient; no direct contact between the fuel clad and the coolant; a core that is more robust for transportation; higher coolant temperature potentially offering higher energy conversion efficiency and hydrogen production capability. 相似文献
137.
In this paper, the debonding strength of axially loaded double shear lap specimens between steel plates and carbon fibre reinforced plastic plates is investigated from the analytical, numerical and experimental point of view. Two steel plates were joined together by two carbon fibre reinforced plastic (CFRP) plates and epoxy adhesive in order to realize double shear lap specimens of different length. Failure of the steel-adhesive interface was identified as the dominant failure mode and fracture mechanics and stress based approach are presented in order to estimate the relevant failure load. A good agreement between the analytical-numerical results and experimental data is achieved. 相似文献
138.
This paper investigates the relationship between absolute energy consumption and gross domestic product (GDP) per capita for 113 countries over the period 1971–2004. Energy has been scarcely explored in the Environmental Kuznets curve (EKC) debate and is taken as the indicator of overall environmental pressure. The following aspects of this work are rather innovative. Firstly, in order to closely adhere to the EKC narratives, the indicator of environmental pressure (energy) is taken in absolute terms rather than per capita. Secondly, we look for consistency both between different econometric techniques (parametric and semi-parametric) and across different analytical levels (world, time series/cross-countries, and single countries). Finally, the dataset is large and not limited to developed countries. 相似文献
139.
Silvano Tosti Angelo Basile Rodolfo Borelli Fabio Borgognoni Stefano Castelli Massimiliano Fabbricino Fausto Gallucci Celeste Licusati 《International Journal of Hydrogen Energy》2009
The ethanol steam reforming reaction carried out in a Pd-based tubular membrane reactor has been modelled via a finite element code. The model considers the membrane tube divided into finite volume elements where the mass balances for both lumen and shell sides are carried out accordingly to the reaction and permeation kinetics. Especially, a simplified “power law” has been applied for the reaction kinetics: the comparison with experimental data obtained by using three different kinds of catalyst (Ru, Pt and Ni based) permitted defining the coefficients of the kinetics expression as well as to validate the model. Based on the Damkohler–Peclet analysis, the optimization of the membrane reformer has been also approached. 相似文献
140.
Tonino Caruso Marta Feroci Achille Inesi Monica Orsini Arrigo Scettri Laura Palombi 《Advanced Synthesis \u0026amp; Catalysis》2006,348(14):1942-1947
Solvent‐ and supporting electrolyte‐free electrolysis in a two‐compartment cell proved to be effective for the direct electroactivation of C H acid‐containing compounds vs. catalytic addition processes. Michael adducts (including quaternary carbon centres) and 2‐nitroalkanols were obtained in very good yields and selectivity on application of a catalytic amount of electricity under galvanostatic conditions. 相似文献