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91.
Magatte Diagne Mamadou Gueye Anicet Dasilva Loic Vidal Adams Tidjani 《Journal of Materials Science》2006,41(21):7005-7010
Nanocomposites of polypropylene-graft-maleic anhydride/clay were prepared by melt blending in an extruder mixer. The nanoscale dispersion of the clay in the polymer was analysed by wide-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results of XRD and TEM showed that the nanocomposites obtained were a kind of intercalated-delaminated structures side by side with different dominant states, depending on the clay used and on the processing conditions. The consequences of photo-oxidation on the thermal stability and fire retardant properties of the nanocomposites were investigated using thermogravimetric analysis and cone calorimetry tests. It appeared that this degradation dramatically affected the important properties of the nanocomposites. A loss of thermal stability and fire retardant performance was observed. This was ascribed to scission reactions that occurred during the oxidative degradation prior to thermal and fire tests. 相似文献
92.
Burle Borís; Allain Sonia; Vidal Franck; Hasbroucq Thierry 《Canadian Metallurgical Quarterly》2005,31(4):831
Although it is widely accepted that control mechanisms are necessary for human behavior to be adapted, very little is known about how such mechanisms are recruited. A suggestion to fill the gap was put forward by M. M. Botvinick, T. S. Braver, C. S. Carter, D. M. Barch, and J. D. Cohen (2001), who proposed the conflict-loop theory. This theory has been successful in accounting for the reduction of compatibility effects after an incompatible trial: The level of conflict being, on average, higher during an incompatible trial, more control occurs after such a trial. The authors have tested this prediction by sorting the trials on the basis of amount of conflict (quantified by the electromyographic activity) they presented. A reduction of the compatibility effect was observed after incompatible trials, but it was independent of the level of conflict on previous trials, suggesting that the conflict does not trigger changes in executive control. Consequences for the conflict monitoring model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Rene Mayrhofer Florian Ortner Alois Ferscha Manfred Hechinger 《Electronic Notes in Theoretical Computer Science》2003,85(3):105
Security and privacy in mobile ad-hoc peer-to-peer environments are hard to attain, especially when working with passive objects (without own processing power, e.g. RFID tags). This paper introduces a method for integrating such objects into a peer-to-peer environment without infrastructure components while providing a high level of privacy and security for peers interacting with objects. The integration is done by associating public keys to passive objects, which can be used by peers to validate proxies (peers additionally acting on behalf of objects). To overcome the problem of limited storage capacity on small embedded objects, ECC keys are used. 相似文献
94.
Recent proposals for multi-paradigm declarative programming combine the most important features of functional, logic and concurrent programming into a single framework. The operational semantics of these languages is usually based on a combination of narrowing and residuation. In this paper, we introduce a non-standard, residualizing semantics for multi-paradigm declarative programs and prove its equivalence with a standard operational semantics. Our residualizing semantics is particularly relevant within the area of program transformation where it is useful, e.g., to perform computations during partial evaluation. Thus, the proof of equivalence is a crucial result to demonstrate the correctness of (existing) partial evaluation schemes. 相似文献
95.
A new approach to formation control of nonholonomic mobile robots equipped with central panoramic cameras is presented. The approach uses motion segmentation techniques to estimate the position of each leader and omnidirectional visual servoing for tracking and collision avoidance. The paper showed that direct feedback-linearization of the leader-follower dynamics leads to asymptotic tracking but suffers from degenerate configurations. A nonlinear controller was presented that avoids such singularities but can only guarantee input-to-state stability of the formation. 相似文献
96.
Industrial control applications are usually developed in two phases: control design and real-time system implementation. In the control design stage a regulator is obtained and later it is translated into an algorithm in the implementation phase. Traditionally, these two phases have been developed in separate ways. Recently, some works have pointed out the necessity of the integration of the control design and its implementation. One of these works reduce the delay variance of control tasks (defined as the control action interval (CAI) and data acquisition interval (DAI) parameters) splitting every task into three parts. The CAI reduction method highly reduces the delay variance and improves the control performance. This work shows how to evaluate these delays under static and dynamic scheduling policies. A new task model is proposed in order to reduce the CAI and DAI parameters, which implies an improvement in the control performance. The new task model will be implemented in a real process, and the experimental measurements will show how, effectively, the control performance is highly improved with the methods presented in this paper. 相似文献
97.
Florian Grond 《AI & Society》2012,27(2):293-295
Safety Certificate is a musical performance based on sensor data from high-speed trains. The original purpose of this data is to provide a basis
for the assessments of the mechanical aspects of train safety. In this performance, the data, which represents dynamical processes
below the audible range, are converted into sound through audification. The sound that is generated live during the performance
is manipulated through the Manta control interface, which allows for the convenient layering of 48 different timbres. Safety Certificate was premiered at Seconde Nature in Aix-en-Provence in March 2010 during the Sonification symposium–What, Where, How, Why, organized by Locus Sonus. The following short article gives details about the data, the audification technique, use of the
control interface, and the musical structure of the performance. 相似文献
98.
A. Ontiveros-Ortega F. Vidal E. Gimenez J. M. Ibáñez 《Journal of Materials Science》2014,49(9):3550-3559
We studied the surface properties of eruptive material from Deception Island (South Shetland Islands, Antarctica). The surface free energy and zeta potential were analyzed in obsidian and pumice stones immersed in different electrolytes (NaCl, BaCl2, AlCl3, VCl2, PbCl2, CdCl2, FeCl3, and CrCl3). The results show that obsidian has a monopolar character. The value of the obsidian electron-donor component increased in the presence of heavy metals, reaching 61.0 mJ/m2 in the case of CrCl3. This means that the heavy metals transform the surface of obsidian into a hydrophilic material in almost all cases, except in the case of FeCl3, which makes the obsidian surface hydrophobic. The pH variation of the liquid phase has a significant influence on the zeta potential, not only changing its value, but also the sign of the surface electric charge. A significant result is that a variation of two in pH (between 5 and 7) changes the sign of the charge from positive to negative or vice versa, depending on the electrolyte used. In general, the presence of electrolytes changes the surface properties of solid materials and consequently the adhesion and growth of microorganisms on coastal rocks. 相似文献
99.
Rosalía López-Ruiz Roberto Romero-González José Luis Martínez Vidal 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(11):1685-1692
The development and validation of a method to determine flonicamid and its metabolites as TFNA (4-trifluoromethylnicotinic acid), TFNG (N-(4-trifluoromethylnicotinoyl) glycine) and TFNA-AM (4-trifluoromethylnicotinamide) in bell pepper samples by ultra-high-performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS) was performed. A fast and simple extraction procedure with acidified acetonitrile and salts (magnesium sulfate and sodium chloride) was used. The methodology was validated, checking for specificity, recovery, precision, limits of detection (LODs) and limits of quantification (LOQs). The recoveries ranged from 84% to 98%, and precisions were lower than 17%. Finally, LODs ranged from 1 µg kg–1 (flonicamid) to 6 µg kg–1 (TFNA-AM), while LOQs ranged from 10 µg kg–1 (flonicamid) to 30 µg kg–1 (TFNA-AM). Bell pepper samples were analysed and concentrations up to 98 µg kg–1 (flonicamid) were detected, although the sum of flonicamid and metabolites did not exceed the maximum residue limit (MRL) set by the European Union. 相似文献
100.
Front Cover: Photoactivatable Mussel‐Based Underwater Adhesive Proteins by an Expanded Genetic Code (ChemBioChem 18/2017) 下载免费PDF全文
Dr. Matthias Hauf Dr. Florian Richter Tobias Schneider Thomas Faidt Dr. Berta M. Martins Dr. Tobias Baumann Dr. Patrick Durkin Prof. Dr. Holger Dobbek Prof. Dr. Karin Jacobs Prof. Dr. Andreas Möglich Prof. Dr. Nediljko Budisa 《Chembiochem : a European journal of chemical biology》2017,18(18):1771-1771