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161.
Yuqing Chen Donal O’Regan Ravi P. Agarwal 《Journal of Applied Mathematics and Computing》2012,38(1-2):63-70
In this paper, we study the anti-periodic problem for semi-linear evolution equations in reflexive Banach spaces. Several existence results are obtained under suitable conditions. 相似文献
162.
Fiona Regan Fiona Walsh James Walsh 《International journal of environmental analytical chemistry》2013,93(7-8):621-631
A novel plasticised PVC polymer membrane as a sensing film for the determination of BTEX compounds using ATR-FTIR spectroscopy is demonstrated. A range of 10 plasticised PVC phases have been investigated using toluene and tetrachloroethylene as test analytes. Both analyte enrichment rates and infrared absorbance values were considered when choosing a suitable polymer for sensing. An enhancement in analyte absorbance at the characteristic IR absorption bands was noted as the plasticiser concentration in the film was increased. 2% PVC with 75% diisooctyl azelate was found to show promising results for simultaneous determination of the BTEX compounds. All BTEX analytes can be measured in less than 8 min. A study of a multicomponent sample demonstrated that analyte enrichment times were influenced by the presence of even one additional analyte component in the sample. 相似文献
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Differential equations with impulses at random moments are set up and investigated. We study the case of Gamma distributed random moments of impulses. Several properties of solutions are studied based on properties of Gammma distributions. Some sufficient conditions for p-moment exponential stability of the solutions are given. 相似文献
167.
Donal O?Regan 《Journal of Mathematical Analysis and Applications》2011,380(2):882-887
We set out a rigorous presentation of Park?s classes of admissible multifunctions and we obtain a fixed point theorem for better admissible multifunctions defined on a proximity space via the Samuel-Smirnov compactification. 相似文献
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Refoldable Foldamers: Global Conformational Switching by Deletion or Insertion of a Single Hydrogen Bond 下载免费PDF全文
Dr. Bryden A. F. Le Bailly Dr. Liam Byrne Prof. Jonathan Clayden 《Angewandte Chemie (International ed. in English)》2016,55(6):2132-2136
Small changes in the structure of a foldamer may lead to gross changes in conformational preference. We show that the simple insertion or deletion of a single hydrogen bond by changes in pH or by photochemical deprotection is sufficient to refold a helical oligomer, interconverting M and P screw‐sense preference. As a consequence of the switch, information may be transmitted to a remote catalytic site, selectively directing the formation of either of two enantiomeric products by a reaction involving 1,22‐remote intermolecular asymmetric induction. 相似文献
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