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91.
Domènech O Morros A Cabañas ME Montero MT Hernández-Borrell J 《Ultramicroscopy》2007,107(10-11):943-947
In the study described here, supported planar bilayers (SPBs) of 1-palmitoy-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE):cardiolipin (CL) (0.8:0.2, mol/mol) were examined using atomic force microscopy (AFM). SPBs were formed from suspensions of POPE:CL (0.8:0.2, mol/mol) in inverted hexagonal (H(II)) phases (buffer containing Ca(2+)). Three laterally segregated domains which differ in height were observed at 24 degrees C. Based on the area accounted for each domain and the nominal composition of the mixture, we interpret that the higher domain is formed by CL, while the intermediate and lower domains (LDs) are formed by POPE. The three domains respond to temperature increase with relative changes in their area. At 37 degrees C, we observed that the increase in the area of the intermediate domain occurs at the expense of the LD. (31)P-nuclear magnetic resonance ((31)P-NMR) and Differential scanning calorimetry (DSC) were used in combination with AFM to characterize the phase behavior of the suspensions and to elucidate the nature of the structures observed. 相似文献
92.
Montero Rafael Agraz Fernando Pagès Albert Spadaro Salvatore 《Photonic Network Communications》2020,40(3):221-232
Photonic Network Communications - Network Slicing appears as one of the enabling technologies for 5G networks to accommodate services with different requirements and availability. The present work... 相似文献
93.
Rafael Moreno-Vozmediano Rubén S. Montero Eduardo Huedo Ignacio M. Llorente 《Journal of Grid Computing》2017,15(2):141-160
Federated cloud networking is needed to allow the seamless and efficient interconnection of resources distributed among different clouds. This work introduces a new cloud network federation framework for the automatic provision of Layer 2 (L2) and Layer 3 (L3) virtual networks to interconnect geographically distributed cloud infrastructures in a hybrid cloud scenario. This framework provides a simple, secure and elastic solution to create and manage federated networks across heterogeneous cloud providers, with abstraction of the underlying technologies. The paper also analyzes the main technologies and topologies that can used the framework to construct L2 and L3 overlay networks within hybrid clouds. In order to demonstrate the viability of the proposed solution and compare the different topologies, the article shows a proof-of-concept of a real federated network deployment in a hybrid cloud, which spans a local private cloud, managed with OpenNebula, and two public clouds, two different regions of Amazon EC2. Results show that L2 and L3 overlay connectivity can be achieved with a minimal bandwidth overhead, lower than 10%. 相似文献
94.
High performance mass spectrometry based proteomics reveals enzyme and signaling pathway regulation in neutrophils during the early stage of surgical trauma 下载免费PDF全文
95.
96.
A pure metallic nickel nanoparticle, spherical in shape, has been successfully synthesized by the chemical reduction of nickel chloride with hydrazine at room temperature without any protective agent and inert gas protection. The effect of nickel salt concentration and the molar ratio of hydrazine to Ni2+ on the properties of the resultant products were investigated by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). Also, the reaction mechanism is discussed in this paper. This synthetic method is proven to be simple and very facile. In addition, it is very interesting to note that the obtained nickel nanoparticle can be isolated in the solid state and stabilized for several months in the atmosphere. 相似文献
97.
M Carmen Gmez‐Guilln Ana Isabel Sarabia M Teresa Solas Pilar Montero 《Journal of the science of food and agriculture》2001,81(7):665-673
This paper examines the effect of a microbial transglutaminase (TGase) on the gelling and viscoelastic properties of a gelatin from megrim (Lepidorhombus boscii) skins. Although TGase extended the setting time of fish gelatin, it was found that melting temperature, gel strength and viscosity in solution at 60 °C were considerably increased by the covalent cross‐linking action of the enzyme, as observed by SDS‐PAGE and SEM. Increasing concentrations of TGase increased the elasticity and cohesiveness of gelatin gels but reduced gel strength and hardness. Partial inactivation of the enzyme was achieved thermally without negatively affecting the properties of the gelatin; whether or not gelatin is thermoreversible depends essentially on the degree of enzyme inactivation. © 2001 Society of Chemical Industry 相似文献
98.
Jooyoun Kim Gerardo Montero Youssef Habibi Juan P. Hinestroza Jan Genzer Dimitris S. Argyropoulos Orlando J. Rojas 《Polymer Engineering and Science》2009,49(10):2054-2061
Cellulose nanoparticles obtained by acid hydrolysis of cellulose paper were used to reinforce polystyrene composite films. The nonionic surfactant sorbitan monostearate was utilized to improve the dispersion properties of the hydrophilic cellulose in hydrophobic matrix and to prevent the formation of aggregates. Turbidity tests were used to measure dispersion stability of the cellulose crystallites in the hydrophobic solvent used in the composite manufacture. A correlation was found between the dispersion stability in solvent and the formation of aggregates in the polymeric composites. Nanocomposite films were processed using a casting/evaporation technique. Thermal and mechanical properties of processed composites were studied by differential scanning calorimetry (DSC) and dynamical mechanical analyses (DMA), respectively. The results showed that the optimum addition of surfactant produced better dispersion of the cellulose particles in the polystyrene matrix and improved the mechanical properties of the resulting composite due to an enhanced compatibility. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers 相似文献
99.
The miscibility of a thermoplastic with the precursors of different epoxy-amine systems was analyzed thermodynamically in which the dependence of interaction parameter on temperature and composition χ (T, ?) and the polydispersity of components were considered. The epoxy-amine precursors were different only in the nature of amino groups, which were provided by a monoamine and a diamine in different proportions. Cloud-point curves were measured for five unreacted modified systems resulting that miscibility of the system increased with the proportion of monoamine. The thermodynamic analysis was realized in two steps: first, the model was applied to each system individually and secondly, a general equation for χ (T, ?) depending on the monoamine-diamine proportion was searched and used to analyze all systems together. Theoretical calculations of cloud-point curves, shadow curves, spinodal curves, critical points, vitrification curves and species distributions were realized and discussed for those systems. 相似文献
100.
MATLAB? software named PRESUD (Pressurized Subunit Design) was developed to identify the optimum solid set sprinkler irrigation subunit design with a criterion of minimizing the annual water application cost (CT). This CT is defined as the cost per cubic meter of water applied to the soil for crop use. In this study, only rectangular subunits are considered, using an iterative method for calculating the lateral and manifold pipelines. The results indicate that water cost (Cw), which includes the investment and operation costs for pumping water from the source to the subunit inlet, makes up 75 % of CT. Another important factor is energy cost, which comprises 14 % of CT. The remaining variables, such as sprinkler spacing and layout, or application rate (ARa), have a lower impact on CT. In cases of use groundwater, the proportion of energy cost in CW can reach 40 %; thus, energy is an important part of CT. Results shows that the criterion of limiting the maximum difference in pressure heads in the irrigation subunit (Δh?20 %), widely used when designing a sprinkler irrigation subunit, does not always lead to a minimum CT, and the use of tools such as PRESUD can help obtain better solutions. 相似文献