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991.
Alexandra Alvarez Fernandez Paul H. J. Kouwer 《International journal of molecular sciences》2016,17(5)
Ionic liquid crystals are materials that combine the classes of liquid crystals and ionic liquids. The first one is based on the multi-billion-dollar flat panel display industry, whilst the latter quickly developed in the past decades into a family of highly-tunable non-volatile solvents. The combination yields materials with a unique set of properties, but also with many challenges ahead. In this review, we provide an overview of the key concepts in ionic liquid crystals, particularly from a molecular perspective. What are the important molecular parameters that determine the phase behavior? How should they be introduced into the molecules? Finally, which other tools does one have to realize specific properties in the material? 相似文献
992.
Clarice Gameiro da Fonseca Pachi Jorge Futoshi Yamamoto Anna Paula Amadeu da Costa Luis Fernandez Lopez 《Scientometrics》2012,93(2):265-278
A relevant factor in the growth of academic productivity in the second half of 20th century is the implementation of the internet, particularly in developing countries. One of the first networks in Brazil is the Academic Network at Sao Paulo (ANSP), a regional network implemented in the state of Sao Paulo, which contains the largest concentration of researchers in the country. This study presents a unique metric for analyzing the impact of ANSP in academic productivity in the state of Sao Paulo. We correlate academic production and available bandwidth using Fisher ideal price index with suitable variables to evaluate the impact of the internet on research centers and universities. We find that the members of ANSP show a steady growth in academic productivity compared with other institutions outside of the ANSP network. These results suggest that policies which increase available bandwidth can positively affect academic productivity. 相似文献
993.
M. Chapartegui J. Barcena X. Irastorza C. Elizetxea M. Fernandez A. Santamaria 《Composites Science and Technology》2012
A study of the requirements necessary to fabricate novel MWCNT buckypaper/benzoxazine nanocomposites, based on rheological results, is presented. Best conditions to infiltrate the resin, without any diluents, in the buckypaper are selected from viscosity data obtained under time–temperature cycles. Infiltration results are analyzed using SEM microphotographs. The nanocomposite is obtained after an adequate curing process of the benzoxazine impregnated buckypaper. The mechanical and electrical properties of the nanocomposite are investigated. The obtained electrical conductivity values are several orders of magnitude larger than the values reported for conventional CNT/polymer nanocomposites. 相似文献
994.
Quintana M. J. Gonzalez R. Fernandez D. Verdeja L. F. 《Protection of Metals and Physical Chemistry of Surfaces》2017,53(2):373-378
Protection of Metals and Physical Chemistry of Surfaces - Protection of conventional steel parts in equipment that must withstand wear of the tribo-corrosion type (combination of heat and an... 相似文献
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Rosfjord CH Webster KE Kahl JS Norton SA Fernandez IJ Herlihy AT 《Environmental science & technology》2007,41(22):7688-7693
Declines in Ca and Mg in low ANC lakes recovering from acidic deposition are widespread across the northern hemisphere. We report overall increases between 1984 and 2004 in the concentrations of Ca + Mg and Cl in lakes representing the statistical population of nearly 4000 low ANC lakes in the northeast U.S. Increases in Cl occurred in nearly all lakes in urbanized southern New England, but only 18% of lakes in more remote Maine had Cl increases. This spatial pattern implicates road salt application as the major source of the increased Cl salts. Among the 48% of the lake population classified as salt-affected, the median changes in Cl (+133 microeq/L) and Ca + Mg (+47 microeq/ L) were large and positive in direction over the 20 years. However, in the unaffected lakes, Cl remained stable and Ca + Mg decreased (-3 microeq/L), consistent with reported long-term trends in base cations of acid-sensitive lakes. This discrepancy between the Cl groups suggests that changes in ion exchange processes in salt-affected watersheds have altered the geochemical cycling of Ca and Mg. One policy-relevant implication is that waters influenced by Cl salts complicate regional assessments of surface water recovery from "acid rain" related to the passage of the Clean Air Act. 相似文献
1000.
In most of its publications, the International Commission on Radiological Protection has highlighted the importance of education and training in radiation protection (RP) for medical exposures. Spain, like other Member States of the European Union, has implemented the Directive and the Guidelines in the medical area. The purpose of this paper is to present the Spanish experience in RP education and training in medicine, the different objectives established according to professional levels, existing regulations and feedback obtained from various RP actions. 相似文献