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991.
Dan Dougherty Pierre Lescanne Luigi Liquori Frdric Lang 《Electronic Notes in Theoretical Computer Science》2005,127(5):57
We present a formalism called Addressed Term Rewriting Systems, which can be used to define the operational semantics of programming languages, especially those involving sharing, recursive computations and cyclic data structures. Addressed Term Rewriting Systems are therefore well suited for describing object-based languages, as for instance the family of languages called , involving both functional and object-based features. 相似文献
992.
Performances of some modern power BJT's in inductive turn-off are experimentally evaluated, by means of an unclamped non-destructive method. The different instabilities exhibited are classified and their influence on device performances is discussed both in clamped and unclamped applicationsAn “Instability Map” is proposed both as a synthetic picture which eases comparison of reverse-bias performances of devices having different ratings, and as an investigation tool for linking device behaviour to its physical features.It results that RBSOA performances are not just related to lateral dimensions of the emitter, but also to metallization lay-out of the chip, which evidently influences current distribution among cells.Finally, stray elements of testing circuit which affect results of RBSOA measurements are investigated, and some suggestions are proposed in order to let measurement results become independent of testing circuit. 相似文献
993.
利用自行设计的金属燃料点火温度测试系统,测试了常压下分别在空气和氧气中的镁包覆硼粉(包覆度20%)、镁粉及铝合金am-Al的点火温度。结果表明,与在空气中相比,3种金属燃料在氧气中的点火温度均有所降低;镁包覆硼粉有效降低了硼的燃点,促进了硼的点火和燃烧,且镁包覆硼粉在氧气中更易燃烧,其点火温度仅为约195.92℃;am-Al在氧气中可点燃,其点火温度低于镁,且燃烧放出的热量最高。在充足的氧气环境下,镁包覆硼粉及am-Al的点火温度均低于300℃,二者均可用作高热值金属燃料。 相似文献
994.
Dr. Valentina Gallo Pasquale Stano Prof. Pier Luigi Luisi 《Chembiochem : a European journal of chemical biology》2015,16(14):2073-2079
Water‐in‐oil (w/o) emulsions are used as a cellular model because of their unique cell‐like architecture. Previous works showed the capability of eukaryotic‐cell‐sized w/o droplets (5–50 μm) to support protein synthesis efficiently; however data about smaller w/o compartments (<1 μm) are lacking. This work focuses on the biosynthesis of the enhanced green fluorescent protein (EGFP) inside sub‐micrometric lecithin‐based w/o droplets (0.8–1 μm) and on its dependence on the compartments’ dynamic properties in terms of solute exchange mechanisms. We demonstrated that protein synthesis is strongly affected by the nature of the lipid interface. These findings could be of value and interest for both basic and applied research. 相似文献
995.
Laurent Pelliser Mathieu Manceau Clotilde Lethiec Delphine Coursault Stefano Vezzoli Godefroy Leménager Laurent Coolen Massimo DeVittorio Ferruccio Pisanello Luigi Carbone Agnes Maitre Alberto Bramati Emmanuelle Lacaze 《Advanced functional materials》2015,25(11):1719-1726
Arrays of liquid crystal defects—linear smectic dislocations—are used to trap semiconductor CdSe/CdS dot‐in‐rods which behave as single‐photon emitters. Measurements of the emission diagram are combined together with measurements of the emitted polarization of the single emitters. It is shown that the dot‐in‐rods are confined parallel to the linear defects to allow for a minimization of the disorder energy associated with the dislocation cores. It is demonstrated that the electric dipoles associated with the dot‐in‐rods, tilted with respect to the rods, remain oriented in the plane including the smectic linear defects and perpendicular to the substrate, most likely due to dipole/dipole interactions between the dipoles of the liquid crystal molecules and those of the dot‐in‐rods. Using smectic dislocations, nanorods can consequently be oriented along a unique direction for a given substrate, independently of the ligands' nature, without any induced aggregation, leading as well to a fixed azimuthal orientation for the dot‐in‐rods' dipoles. These results open the way for the fine control of nanoparticle anisotropic optical properties, in particular, fine control of single‐photon emission polarization. 相似文献
996.
Application of response surface methodology to evaluate the effect of dry‐spinning parameters on poly (ε‐caprolactone) fiber properties 下载免费PDF全文
Bahareh Azimi Parviz Nourpanah Mohammad Rabiee Shahram Arbab Maria Grazia Cascone Andrea Baldassare Luigi Lazzeri 《应用聚合物科学杂志》2015,132(24)
Poly (ε‐caprolactone) fibers were prepared by dry‐spinning method. The effect of processing parameters on linear density, mechanical, and morphological properties of fibers was investigated using the response surface methodology (RSM). This method allowed evaluating a quantitative relationship between polymer concentrations, spinning speed, and draw ratio on the properties of the fibers. Polynomial regression model was fitted to the experimental data to generate predicted response. The results were subjected to analysis of variance to determine significant parameters. It was found that all three parameters had significant effect on linear density of fibers. Combined effect of concentration and spinning speed was observed in which the linear density of fiber was more sensitive to changes in the solution concentration at lower spinning speed. Polymer concentration had the largest influence on the mechanical properties of fibers. An average cross‐sectional radius of fibers was affected by concentration and draw ratio in opposite manner. Among all three parameters, only polymer concentration had significant effect on circularity of fiber cross sections. By applying the RSM, it was possible to obtain a mathematical model that can be used to better define processing parameters to fabricate dry‐spun PCL fiber in a more rational manner. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42113. 相似文献
997.
The effect of processing routes on the thermal and mechanical properties of poly(urethane‐isocyanurate) nanocomposites 下载免费PDF全文
A systematic investigation of four processing routes was implemented so as to evaluate the thermal and mechanical properties of nanosilica (NS) reinforced poly(urethane‐isocyanurate) nanocomposites (NC). The NS dispersion in the Polmix and the Isomix routes was performed in the polyol and the isocyanate precursor, respectively. The Isopol and the Solvmix routes consisted on the dispersion of the filler after the mixing of the precursors and with the aid of solvents, respectively. The NS dispersion, fractography (SEM, TEM), flexural and tensile mechanical properties, thermogravimetric analysis and FTIR analysis of NCs was performed as a function of processing route, isocyanate index, and NS concentration. Each route produced a NC with distinct properties, which were correlated to the NS agglomeration degree and how the NS affected the thermal transitions of the HS and the relative ratio of urethane and isocyanurate chemical groups. For example, the NC prepared with the Polmix route had substantial improvements of σt and εt of around +40 and +52%, respectively and an improved thermal resistance of the Hard Segments. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42750. 相似文献
998.
Dasiel O. Borroto-Escuela Ismel Brito Wilber Romero-Fernandez Michael Di Palma Julia Oflijan Kamila Skieterska Jolien Duchou Kathleen Van Craenenbroeck Diana Suárez-Boomgaard Alicia Rivera Diego Guidolin Luigi F. Agnati Kjell Fuxe 《International journal of molecular sciences》2014,15(5):8570-8590
G protein-coupled receptors (GPCRs) oligomerization has emerged as a vital characteristic of receptor structure. Substantial experimental evidence supports the existence of GPCR-GPCR interactions in a coordinated and cooperative manner. However, despite the current development of experimental techniques for large-scale detection of GPCR heteromers, in order to understand their connectivity it is necessary to develop novel tools to study the global heteroreceptor networks. To provide insight into the overall topology of the GPCR heteromers and identify key players, a collective interaction network was constructed. Experimental interaction data for each of the individual human GPCR protomers was obtained manually from the STRING and SCOPUS databases. The interaction data were used to build and analyze the network using Cytoscape software. The network was treated as undirected throughout the study. It is comprised of 156 nodes, 260 edges and has a scale-free topology. Connectivity analysis reveals a significant dominance of intrafamily versus interfamily connections. Most of the receptors within the network are linked to each other by a small number of edges. DRD2, OPRM, ADRB2, AA2AR, AA1R, OPRK, OPRD and GHSR are identified as hubs. In a network representation 10 modules/clusters also appear as a highly interconnected group of nodes. Information on this GPCR network can improve our understanding of molecular integration. GPCR-HetNet has been implemented in Java and is freely available at http://www.iiia.csic.es/~ismel/GPCR-Nets/index.html. 相似文献
999.
1000.
采用真空熔烧工艺在SiC陶瓷表面制备了三种化学成分的Mo-Ni-Si金属化涂层,研究涂层的相组成和涂层/SiC陶瓷界面的微结构。通过座滴法实验考察纯Ag在SiC陶瓷涂层上的润湿与铺展特性,分析和讨论了Ag/金属化SiC陶瓷体系的界面行为。实验结果表明,该金属化涂层主要由Mo5Si3, MoSi2, Ni2Si, NiSi2 和MoNiSi组成,同时随着涂层中Mo的摩尔比由20%增加至40%,位于涂层表面的具有四方结构的MoSi2晶粒逐渐消失。Ag对Mo20-Ni32-Si48、Mo30-Ni28-Si42、Mo40-Ni24-Si36金属化SiC陶瓷在1000 oC保温30分钟后对应的最终接触角分别为45o, 79o 和 85o,该结果与Ag滴和三种Mo-Ni-Si涂层之间的相互作用密切相关。同时在润湿试验前后,在Mo-Ni-Si涂层/SiC衬底界面没有发现明显的反应层。 相似文献