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941.
This paper discusses responses of the city council in Palermo to trends in immigration, in the context of the long-term physical decline of the historic centre. The paper describes these trends, the role and needs of ethnic minorities and problems related to their living conditions in the historic centre. It goes on to assess whether the specific issue of planning and ethnic minorities can suggest new approaches to a wider re-analysis of planning practices.  相似文献   
942.
This paper presents results summary of an experimental investigation aimed at evaluating the influence of the bolt diameter on the bearing failure strength of glass fibre reinforced polymer (GFRP) bolted laminates with epoxy matrix, for different values of fibre-to-load inclination angle. In this study, three different types of laminates were tested: one of them is mono-directional while the other two are bi-directional, with two different stacking sequence. Reductions in the pin-bearing ultimate load was found to be linearly dependent on bolt diameter. A pin-bearing design formula is also proposed based on experimental results.  相似文献   
943.
Thermodynamics and kinetics of phase transformation in intercalation battery electrodes are investigated by phenomenological models which include a mean-field lattice-gas thermodynamic model and a generalized Poisson-Nernst-Planck equation set based on linear irreversible thermodynamics. The application of modeling to a porous intercalation electrode leads to a hierarchical equivalent circuit with elements of explicit physical meanings. The equivalent circuit corresponding to the intercalation particle of planar, cylindrical and spherical symmetry is reduced to a diffusion equation with concentration dependent diffusivity. The numerical analysis of the diffusion equation suggests the front propagation behavior during phase transformation. The present treatment is also compared with the conventional moving boundary and phase field approaches.  相似文献   
944.
945.
946.
Aryl α‐diimine derivatives have been used, for the first time, as efficient new ligands for the palladium‐catalyzed oxidative bis‐alkoxycarbonylation reaction of olefins. The most active catalyst was formed in situ from bis(9‐anthryl)‐2,3‐dimethyl‐1,4‐diazabutadiene and palladium(II) trifluoroacetate [Pd(TFA)2]. This catalytic system was able to selectively convert olefins into succinic diesters in good yields (up to 97%) and low catalyst loading (up to 0.5 mol%) under mild reaction conditions [4 bar of carbon monoxide (CO) at 20 °C in the presence of p‐toluenesulphonic acid as additive and p‐benzoquinone as oxidant]. The optimized conditions could be successfully applied to both aromatic and aliphatic olefins, by using methanol, benzyl alcohol or isopropyl alcohol as nucleophiles.

  相似文献   

947.
The study is focused on the extraction of valuable metals from automotive shredder residue (ASR) by different leaching solutions. First, ASR samples were roasted at 600 °C to simulate a thermal treatme...  相似文献   
948.
Monosaccharide lipid A mimetics based on a glucosamine core linked to two fatty acid chains and bearing one or two phosphate groups have been synthesized. Compounds 1 and 2 , each with one phosphate group, were practically inactive in inhibiting LPS‐induced TLR4 signaling and cytokine production in HEK‐blue cells and murine macrophages, but compound 3 , with two phosphate groups, was found to be active in efficiently inhibiting TLR4 signal in both cell types. The direct interaction between compound 3 and the MD‐2 coreceptor was investigated by NMR spectroscopy and molecular modeling/docking analysis. This compound also interacts directly with the CD14 receptor, stimulating its internalization by endocytosis. Experiments on macrophages show that the effect on CD14 reinforces the activity on MD‐2 ? TLR4 because compound 3 's activity is higher when CD14 is important for TLR4 signaling (i.e., at low LPS concentration). The dual targeting of MD‐2 and CD14, accompanied by good solubility in water and lack of toxicity, suggests the use of monosaccharide 3 as a lead compound for the development of drugs directed against TLR4related syndromes.  相似文献   
949.
PET radiotracer development to target in vivo P‐glycoprotein (P‐gp) could be an important strategy for the early diagnosis of neurodegenerative disorders such as Alzheimer’s disease (AD). Indeed, as a dysfunction of P‐gp is responsible for the accumulation of β‐amyloid plaques (a hallmark of AD) in brain parenchyma, P‐gp is the cause of AD onset. P‐gp substrates and inhibitors are useful for imaging the activity or expression of this protein, respectively; herein we discuss the in vivo evaluation of some 11C radiotracers with P‐gp‐inhibitory activity, such as [11C]MC18 and [11C]MC113, as well as P‐gp substrates [11C]MC266 and [11C]MC80. Moreover, the radiosynthesis of all these P‐gp probes is reported.  相似文献   
950.
Novel hybrid materials composed by a high density polyethylene (HDPE) matrix and powdered rubber coming from scrap tyres (ground tyre rubber [GTR]) were prepared. Two methods were followed: ethylene was polymerized by a metallocene catalyst (Cp2ZrCl2/methylaluminoxane) in the presence of a toluene dispersion of the filler (in‐situ polymerization); and the ethylene was polymerized out after supporting the aluminum‐based co‐catalyst onto the rubber particles surface (polymerization filling technique). The experimental conditions were varied in order to achieve the best catalyst productivity. All the synthesized composites were characterized in order to investigate the occurrence and the extent of interactions between HDPE macromolecular chains and the GTR components and their effects onto the final properties, by comparison with a composite where GTR was included into the matrix through blending in the melt. Scanning electron microscopy, atomic force microscopy, and solvent extractions were performed to this aim. The amount of thermoplastic matrix bonded to the filler was determined, and the extracted polymer was characterized by size exclusion chromatography and differential scanning calorimetry. Finally, stress–strain behavior of the composites obtained, respectively, by catalytic polymerization and melt mixing was compared. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40313.  相似文献   
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