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排序方式: 共有387条查询结果,搜索用时 15 毫秒
91.
Molecular mechanisms of mammalian global genome nucleotide excision repair   总被引:19,自引:0,他引:19  
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92.
A new, simple, and fast one-pot synthesis of supported Au or Ag nanoparticles is implemented, for which a reactive Fe(II)-bearing green rust inorganic particle is used as an individual micro-reactor acting as both the reducing agent and support for the resulting metal nanoparticles. The mechanism involves both the solid-state oxidation of the green rust support (sulfate or carbonate) and the reduction-precipitation of soluble metal precursor. The resulting nanohybrids have a platy inorganic part supporting about one to ten nanoparticles with sizes in the 20 to 120 nm range.  相似文献   
93.
The aim of this study was to analyze the rat temporomandibular joint (TMJ) synovial membrane at different ages using light, scanning, and transmission electron microscopy. Under light microscopic analysis, the TMJ structures were observed such as condyle, capsule, disk, the synovial membrane collagen type, and cells distribution. In the scanning electron microscopy, the synovial membrane surface exhibited a smooth aspect in young animals and there was an increase with ageing in the number of folds. The transmission electron microscopic analysis showed more synoviocytes in the synovial layer in the young group and still a great number of vesicles and cisterns dilation of rough endoplasmic reticulum in the aged group. In the three groups, a dense layer of collagen fibers in the synovial layer and cytoplasmic extensions were clearly seen. It was possible to conclude that synovial membrane structures in aged group showed alterations contributing to the decrease in joint lubrication and in the sliding between disk and joint surfaces. These characteristic will reflect in biomechanics of chewing, and may cause the TMJ disorders, currently observed in clinical processes. Microsc. Res. Tech. © 2012 Wiley Periodicals, Inc.  相似文献   
94.
The design of fluorophores merging circularly polarized luminescence and thermally activated delayed fluorescence properties has recently emerged as a promising direction for the development of efficient CP-Organic Light-Emitting Diodes (CP-OLEDs). This progress report gives an overview of the molecular designs explored to obtain CP-TADF properties, of their performances as chiral emitters in CP-OLEDs, and discusses future challenges for this burgeoning field of research.  相似文献   
95.
Oxidation of Metals - The materials used for the design of solar receivers are one of the critical parts of the concentrated solar power (CSP) plants. An increase in the working temperature of a...  相似文献   
96.
Ultra-high temperature ceramics having melting points above 3500 K and high thermal conductivities are envisaged as future receivers of concentrating solar power plants. The high pressure and solar temperature reactor (Réacteur Hautes Pression et Température Solaire, REHPTS) implemented at the focus of the Odeillo 5 kW solar furnace was used to investigate the oxidation of three refractory carbides containing different sintering additives (HfC/MoSi2, ZrC/MoSi2, ZrC/TaSi2) that could be considered as promising candidates. The concentration of the additive, TaSi2 or MoSi2, was 20 vol%. Each kind of sample was oxidized in air for 20 min at 1800, 2000 and 2200 K. Experiments were filmed using a video camera and the gaseous phases were analyzed in situ by mass spectrometry. Various post-test characterizations have shown that the nature of the carbide and additive strongly affects the composition of the oxide layer and therefore the high-temperature behaviour.  相似文献   
97.
Component‐oriented software has become a useful tool to build larger and more complex systems by describing the application in terms of encapsulated, loosely coupled entities called components. At the same time, asynchronous programming patterns allow for the development of efficient distributed applications. While several component models and frameworks have been proposed, most of them tightly integrate the component model with the middleware they run upon. This intertwining is generally implicit and not discussed, leading to entangled, hard to maintain code. This article describes our efforts in the development of the GCM/ProActive framework for providing distributed and adaptable autonomous components. GCM/ProActive integrates a component model designed for execution on large‐scale environments, with a programming model based on active objects allowing a high degree of distribution and concurrency. This new integrated model provides a more powerful development, composition, and execution environment than other distributed component frameworks. We illustrate that GCM/ProActive is particularly adapted to the programming of autonomic component systems, and to the integration into a service‐oriented environment. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
98.
The effective mechanical properties of a polyurethane adhesive (oligoetherdiol, ‐triol, MDI) in gold joints (bond line thickness, dP = 35–550 µm) are studied in the linear deformation range by dynamic mechanical analysis in shear mode. These properties depend on dP: thin ones possess a higher dynamic glass transition temperature and show a narrower glass transition than the thick ones. The storage modulus rises with decreasing dP for the rubbery plateau. The results attest mechanical interphases in the polyurethane with increased crosslink density and reduced cooperative mobility than in bulk. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42058.  相似文献   
99.
This work considers the potential future use of hydrogen in fuel cell electrical vehicles to face problems such as global warming, air pollution, energy security and competitiveness. The lack of current infrastructure has been identified as one of the main barriers to develop the hydrogen economy. This work is focused on the design of a hydrogen supply chain through mixed integer linear programming used to find the best solutions for a multi-objective optimization problem in which three objectives are involved, i.e., cost, global warming potential and safety risk. This problem is solved by implementing an ?-constraint method. The solution consists of a Pareto front, corresponding to different design strategies in the associated variable space. Multiple choice decision making is then recommended to find the best solution through an M-TOPSIS analysis. The model is applied to the Great Britain case study previously treated in the dedicated literature. Mono and multicriteria optimizations exhibit some differences concerning the degree of centralization of the network and the selection of the production technology type.  相似文献   
100.
Macroporous polyamines containing β-cyclodextrin (β-CD) are used for the recovery of various organic pollutants from aqueous solutions. Several insoluble polyamines with various degrees of β-CD were prepared. Studies concerning the sorption kinetics, the effect of pollutant concentration, pH of the solutions, and β-CD content are presented here. The results of sorption experiments show that these sorbents exhibit high sorption capacities toward substituted phenolic derivatives. The mechanism of sorption is both physical adsorption in the resin polymer network through acid–base interactions, ion exchange, and hydrogen bonding due to the amino groups and the formation of an inclusion complex due to the β-CD molecules through host–guest interactions, and hydrophobic interactions such as guest–guest interactions. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2903–2910, 1999  相似文献   
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