6,058 research outputs found
Development and Assessment of Passive air sampler for Sampling Semi-Volatile Organic Compounds
Earth & Environmental SciencesAs increasing about concerns of air quality, demand of air samplers is also increasing. Among the air pollutants, SVOCs are important pollutants because of their toxic properties. There are mainly two sampling method for collecting SVOCs. One is active air sampling and the other is passive air sampling. Most of existing passive air samplers can only collect gaseous phase. However for correct assessment of air quality, passive air samplers which collect both gaseous and particulate phase SVOCs are needed. In this study, we developed new passive air samplers for SVOCs, and we verified the sampler’s ability. Among the SVOCs, we selected 16 EPA priority PAHs as target compounds. We deployed 16 samplers and periodically recovered during 120 days. We also sampled with active air sampler for obtaining the real value of air concentrations. We analyzed the recovered samples with GC/MS. During sampling period, 8 compounds showed linearity in gaseous phase, and 14 compounds had linearity in particulate phase. There were tendency that heavier compounds were distributed in particulate phase, however lighter compounds were mainly distributed in gaseous phase. Both of samples which were obtained from actively and passively sampling were showed similar patterns. The cacluated uptake rates are 2 ng/m3 ~ 21 ng/m3 in gaseous phase PAHs, and 0.073 ng/m3 to 18 ng/ m3 in particulate phase PAHs. We identified the ability of developed passive air samplers, and this passive air sampler will be useful for assessing the air quality.ope
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Style And Performance Aspects In The Newly Published Piano Sonata By Witold Lutos?awski
Polish composer Witold Lutos?awski (1913-1994) was one of the most representative composers of the twentieth-century. Lutos?awski’s style progressed from traditional to modern avant-garde. His Piano Sonata belongs to his first compositional period, and is the only extant work from his student years. His remarkable synthesis of classical structures and impressionistic harmonic sonorities distinguishes the Sonata. Lutos?awski’s Piano Sonata is divided into three movements, and each movement is written in traditional sonata allegro form, sonata form without development and modified sonata form respectively. The Sonata contains both considerable elements of Classicism and Impressionism, as well as traits of Post-romanticism and Neoclassicism. The evolution of Lutos?awski’s compositional language can be better understood through an in-depth study of his Piano Sonata. Although Lutos?awski did not allow the work to be published during his lifetime, this occurred posthumously, ten years after the composer´s death. The recent publication of the work, paired with its substantial technical demands, both account for the fact that the Sonata is not frequently performed. The complex textures of Sonata place extensive technical and musical demands on the performer. In this study, a detailed description of the composer´s early style and influences as relates to this work will be analyzed and technical and pianistic approaches necessary for a performance of the work will be addressed. Also, there are significant discrepancies between the manuscript and printed score, even though the edition is based on the manuscript. Only one manuscript survives and scholarly research involving the work is scarce. Discrepancies between the manuscript and the published edition will be detailed, with suggestions for performance. It is hoped that this study will provide interest and be conducive to better approach the performance of this Piano Sonata
Doubly responsive polymersomes towards monosaccharides and temperature under physiologically relevant conditions
Organoboronic acid-containing polymers and block copolymers have recently attracted attention because of their ability to recognize important natural diol compounds such as saccharides and nucleotides under physiologically relevant conditions at neutral pH. In particular, polymers and block copolymers that are responsive toward multiple stimuli can be utilized to create smart delivery vehicles for use in applications in a complex environment. Here we report the monosaccharide-responsive polymers and block copolymers comprising styreneboroxole and oligo(ethylene glycol)-functionalized styrenes (OEG-STs) as repeating units. We have shown that homopolymers and copolymers of OEG-STs are thermally responsive by demonstrating that they possess the characteristic of tunable lower critical solution temperature (LCST) in water. When copolymerized with OEG-STs, styreneboroxole units function as a switch to change the solubility of the resulting polymers in aqueous solution by recognizing mono-saccharides via the formation of boronate ester. By introducing the minimum number of monosaccharide-responsive styreneboroxole units onto the thermally responsive OEG-ST backbone, we demonstrated the monosaccharide-responsive behavior of the resulting copolymers and their amphiphilic block copolymers in aqueous solution at physiologically relevant pH and temperature. A strategy based on doubly responsive block copolymers reported here could be utilized as new delivery vehicles for cargo molecules such as insulin, due to their ability to function in an in vivo environmentopen
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