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951.
The large-scale commercialization of aluminum-matrix composites   总被引:2,自引:0,他引:2  
The successful commercialization of aluminum composites depends on much more than just the development of the material and the discovery of suitable applications. In order for large potential users to consider a new material adequate production capacity must be demonstrated and costs must be reduced to levels consistent with the products targeted. For all potential applications, appropriate secondary fabrication techniques must be developed. Recycling and reclamation assume a special importance in particularly cost-sensitive markets, such as automobiles, as they have a sizable impact on the final cost of a component. Finally, suitable analytical techniques are required by all parties, including the material producer, secondary fabricators, and end-users. While many of these enabling technologies will eventually be further developed and refined by fabricators and end-users, the initial development, in most cases, has been left to the materials producer.  相似文献   
952.
953.
A widely operated way to treat industrial air loaded with VOCs is the absorption technique. For this, the choice of a well-adapted solvent is obviously of prime importance. In the present work an absorption process using viscous organic absorbents, namely, phthalates was studied to scrub flue gases. A suitable thin film device, the cables-bundle contactor, was applied both to favor mass transfer and to limit the pressure drops, and various experiments were achieved at the pilot-scale. Correlations predicting hydrodynamic and mass transfer parameters (interfacial area, liquid hold-up, liquid phase mass transfer coefficients) essential for the design of industrial absorption units, were deduced from experimental results. A comparison of performances of the cables contactor and a packed bed scrubber of same void fraction was made for absorption of toluene into DEHP.  相似文献   
954.
In the present study two synthetic mesoporous carbons, a highly ordered CMK-3 sample with hexagonal structure and a disordered mesoporous carbon (denoted DMC) were investigated for the sorption of Remazol Red 3BS (C.I. 239) dye in comparison to three commercial activated carbons and a HMS mesoporous silica with a wormhole pore structure. The structural, porosity and surface characteristics of the materials were evaluated using XRD, TEM, N2 porosimetry, FT-IR spectroscopy and zeta-potential measurements. Optimal dye sorption occurred at pH ~2. Equilibrium sorption data followed the Langmuir model and showed that the two synthetic mesoporous carbons exhibit higher sorption capacities (qmax  500–580 mg/g at 25 °C) in comparison to the commercial activated carbons which possessed either microporous (Takeda 5A and Calgon carbon) or combined micro-/mesoporous (Norit SAE-2) structures and to the HMS mesoporous silica. Thermodynamic parameters as the change in free energy, enthalpy, and entropy of sorption were also estimated. Kinetic studies were carried out and showed a rapid sorption of dye in the first ca. 30 min while equilibrium was reached after ca. 3 h. The sorption kinetics of dye was best described by a second-order kinetic model. A surfactant enhanced carbon regeneration (SECR) technique was used to regenerate the dye-loaded carbon sorbents.  相似文献   
955.
Skim natural rubber latex is a protein‐rich byproduct obtained during the centrifugal concentration of natural rubber latex. Skim latex has a very low dry rubber content (4–8%), and the rubber particles are smaller in size. It has a higher proportion of nonrubber solids, which are mostly proteinaceous in nature. It is difficult to coagulate, and it takes more processing time. The proteins in skim latex can be decomposed by proteolytic enzymes. This article discusses the use of stabilized liquid papain from the papaya plant (Carica papaya) for deproteinization followed by creaming for quick and easy coagulation of skim latex. The technological properties and aging characteristics of the deproteinized skim rubber are compared with those of conventionally prepared skim rubber and block rubber. The deproteinized skim rubber showed enhanced quality parameters. Particle size analysis revealed that deproteinization and creaming of the skim latex did not markedly change the particle size. Gel permeation chromatography showed a reduction in the quantity of fatty acids after deproteinization and creaming, which was reflected in the improvement of the aging characteristics in comparison with the control sample. Vulcanizates prepared with the deproteinized skim rubber had higher resilience, lower heat buildup, lower compression set, and good tensile strength and elongation at break in comparison with conventionally prepared skim rubber, and the properties were almost comparable to those of block rubber. The improvement in the mechanical properties and aging characteristics could be attributed to the reduction of the protein content, the partial removal of unsaturated fatty acids, and the removal of metal ions that were pro‐oxidants during the deproteinization and creaming process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
956.
Telmisartan was originally designed as an AT1 antagonist but was later also characterized as a selective PPARγ modulator. This study focused on the identification of the essential structural motifs of telmisartan for PPARγ activation activity, elucidating the individual SAR of each different component (shown).

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957.
Plaque visualisation : We identified three different D ‐enantiomeric peptides that bind to Alzheimer's amyloid β (Aβ1‐42). As there is currently no definitive pre‐mortem diagnosis for Alzheimer's disease, we investigated the peptides' suitability as molecular probes for in vivo imaging in transgenic mouse models.

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958.
The CoxZn1?xAl2O4 system (x = 0; 0.1; 0.3; 0.5; 0.7; 0.9 and 1) was synthesized by the polymeric precursor method and characterized by the techniques XRD, TG-DTA, IR, UV–vis and colorimetry. The XRD patterns displayed the characteristic peaks of the spinel structure and a good crystallinity. The DTA curves showed an exothermic peak corresponding to the enthalpy of the transition taking place at about 700 °C. The infrared spectra displayed vibrations at about 650, 550, 540, 520, 500, 490 cm?1, which were ascribed to the spinel structure. The UV–vis spectra presented three bands at 550, 580 and 620 nm attributed to the Co2+ spin transitions in tetrahedral sites. The colorimetric data point out the formation of blue pigments, corresponding to highly negative values of b1. The lightness, coordinate L1, increases with the heat treatment temperature. These facts reveal that CoxZn1?xAl2O4 is a promising system that can be employed to obtain ceramic blue pigments.  相似文献   
959.
The dielectric response in the microwave field of polyaniline prepared at different temperatures and using different inorganic and organic dopants was studied. Chemical oxidative polymerization of aniline was done at low temperature (0–5°C), at room temperature, and at high (60°C) temperature using different inorganic dopants like HCl, HNO3, H2SO4, HClO4, etc. Polyaniline was also prepared with different organic dopants like camphor sulfonic acid, Toluene sulfonic acid, and Naphthalene sulfonic acid. All polymers formed were characterized using IR, TGA, DSC, and SEM, etc. The dielectric responses of all polymers are studied using cavity perturbation technique in the microwave field. The studies indicates that the polyaniline prepared with perchloric acid at room temperature shows higher conductivity and absorption coefficient compared with all other samples. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
960.
Probing SAR : The 1‐(biphenyl‐4‐ylmethyl)‐1H‐benzo[d]imidazole moiety is known to be an essential structural component of telmisartan for PPARγ activation. This study focused on the substituents at position 2 of the benzimidazole in an attempt to optimize PPARγ activation. In particular, the elongation of the alkyl chain and the introduction of an aromatic ring system were studied (shown).

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