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491.
Antoni Sym 《Fluid Dynamics Research》1988,3(1-4):151-156
The paper summarizes a solution generation technique for the Localized-Induction-Approximation eqs. based on the approach of soliton surfaces. The technique is then applied to compute a four-real-parameter family of localized excitations of an arbitrary vortex filament motion of Kida class. The resulting formulae involve Jacobi theta functions. 相似文献
492.
493.
Joanna Faber Krzysztof Brodzik Anna Gołda-Kopek Damian Łomankiewicz Jan Nowak Antoni Świątek 《Chemical Papers》2015,69(6):799-809
The investigation of air pollution is a highly important field of research. Air quality in a vehicle’s interior has attracted growing attention since people spend much of their time in vehicles and those frequently travelling in new cars are exposed to harmful compounds. The main air pollutants inside new vehicles are volatile organic compounds (VOCs), present as a result of interior materials’ de-gassing. Among the sampling methods used in indoor air quality research, active sampling for VOCs collection is one method that has been extensively described and applied. The present study sought to implement passive sampling with Radiello® samplers to collect air samples directly in the car factory. The results from passive sampling were compared with results derived from active sampling using Carbograph 1TD and silicagel coated with 2,4-dinitrophenylhydrazine cartridges, based on previously validated methods. The identification and quantification of organic compounds was performed using gas chromatography with flame ionisation coupled with a mass spectrometer after thermal desorption. Aldehydes were determined by means of high-performance liquid chromatography. In the present study, the results obtained with the use of active and passive methods of air sampling were compared, correlations between the two sampling methods were designated and the repeatability of passive sampling was detailed. 相似文献
494.
Jacek yczko Jacek Piotr Twardowski Bartomiej Skalny Renata Galek Antoni Szumny Iwona Gruss Dariusz Piesik Sebastian Sendel 《Molecules (Basel, Switzerland)》2021,26(9)
Rare carnivorous plants representing the genus Sarracenia are perceived as very interesting to scientists involved in various fields of botany, ethnobotany, entomology, phytochemistry and others. Such high interest is caused mainly by the unique capacity of Sarracenia spp. to attract insects. Therefore, an attempt to develop a protocol for micropropagation of the Sarracenia alata (Alph.Wood) Alph.Wood, commonly named yellow trumpets, and to identify the specific chemical composition of volatile compounds of this plant in vitro and ex vivo was undertaken. Thus, the chemical volatile compounds excreted by the studied plant to attract insects were recognized with the application of the headspace solid-phase microextraction (HS-SPME) coupled with the GC-MS technique. As the major volatile compounds (Z)-3-hexen-1-ol (16.48% ± 0.31), (E)-3-hexen-1-ol acetate (19.99% ± 0.01) and β-caryophyllene (11.30% ± 0.27) were identified. Further, both the chemical assumed to be responsible for attracting insects, i.e., pyridine (3.10% ± 0.07), and whole plants were used in in vivo bioassays with two insect species, namely Drosophila hydei and Acyrthosiphon pisum. The obtained results bring a new perspective on the possibilities of cultivating rare carnivorous plants in vitro since they are regarded as a valuable source of bioactive volatile compounds, as including ones with repellent or attractant activity. 相似文献
495.
Yuriy A. Knirel Evgeny V. Vinogradov Alexander S. Shashkov Zygmunt Sidorczyk Antoni Rozalski Ioanna Radziejewska-Lebrecht 《Journal of carbohydrate chemistry》2013,32(4-5):379-414
Abstract Proteus bacteria are important human opportunistic pathogens which frequently cause urinary tract infections. According to Bergey's Manual of Systematic Bacteriology,1 this genus includes three species: P. mirabilis, P. vulgaris, and P. myxofaciens. A novel species of P. penneri has been recently proposed2,3 for strains formerly called P. vulgaris biogroup I. Proteus is an antigenically heterogeneous group of bacteria, and this is mainly associated with diverse composition and structures of O-specific polysaccharide chains of outer-membrane lipopolysaccharides (O-antigens). The Kauffman-Perch serological classification4 of P. mirabilis and P. vulgaris includes 49 O-serogroups. However, a number of S-strains remain unclassified,5 including strains of P. penneri. 相似文献
496.
Charles Ng Xiangju Kong Dr. Dongxia Wu Dr. Min Song Dr. Xiaohong Shi Xiaochun Xu Wei‐Han OuYang Rongxian He Prof. Xing‐Zhong Zhao Tom Lee Prof. F. Charles Brunicardi Dr. Mitch André Garcia Prof. Antoni Ribas Prof. Roger S. Lo Prof. Hsian‐Rong Tseng 《Angewandte Chemie (International ed. in English)》2013,52(12):3533-3533
497.
498.
We provide a tour of Barcelona, Catalonia, Spain, following four routes through the city and one elsewhere in the city and beyond, focusing on sites of importance in physics. Route 1 covers the Old Town, its Gothic Quarter, Plaça del Rei, Plaça de Sant Jaume, and Jewish Quarter. Route 2 identifies sites on and close to La Rambla, the main promenade in the city. Route 3 goes from the medieval shipyards to the Board of Commerce to Citadel Park. Route 4 concentrates on the Extension (Eixample) and covers the restored University, the Industrial University, and the new campus of the University of Barcelona. Elsewhere in the city and beyond are the Fabra Observatory; the Plaça de les Glòries with its large steel sculpture depicting the meridian arc from Dunkirk to Barcelona; Montjuïc, the site of the National Art Museum of Catalonia; and the National Museum of Science and Technology in Terrassa. 相似文献
499.
Gas turbine propulsion and aircraft engines involve a great number of rotating shrink-fit assemblies. In presence of high-speed rotations and thermal effects, the reliability of such components with respect to contact separation and failure occurrences needs to be analyzed in the very early design of those structures. In particular, engineers and designers are to prescribe an adequate shrink interference to ensure a structural safe life for a given range of operating conditions. This paper is devoted to the determination of those critical contact and plastic states. To that end, a thermo-elastic–plastic analytical model of a rotating shrink-fit assembly is studied. The stress distributions and contact/plasticity/failure conditions are then derived analytically. In the last part, the determination of the safe operating domain and optimum shrink interference is illustrated through a numerical example. 相似文献