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31.
Modeling Studies of the Formation and Destruction of NO in Pulsed Barrier Discharges in Nitrogen and Air 总被引:1,自引:0,他引:1
This paper presents the results of modeling studies on the formation and destruction of NO in pulsed barrier discharges in nitrogen and air. The goals of this work are to identify the major processes involved in the formation and destruction of NO in air discharges, to distinguish between oxidative and reductive paths for NO destruction, to explore the potential importance of excited state reactions, to evaluate the role of water in such systems, and to identify the final products in the absence of heterogeneous processes. In all cases, the systems were modeled with 100×10–4% (100 ppm) of added NO, with and without 3% added water. The focus in all of this work is chemistry in the post-pulse regime. 相似文献
32.
YiJianCHEN GuiYingXU ShiLingYUAN HaiYingSUN 《中国化学快报》2005,16(5):688-690
Molecular dynamics (MD) simulation are used to study the properties of gemini surfactant of ethyl-α,ω-bis(dodecyldimethylammonium bromide) (C12C2C12) and dodecyl-trimethylammonium bromide (DTAB) at the air/water interface, respectively. In the two systems,t he surfactant concentrations are both 28 wt.%, and other conditions are also the same. After reaching the thermodynamic equilibrium, the concentration profiles, the radial distributions functions (RDF) and the mean squared displacement (MSD) are investigated. The results reveal that the surface activity of C12C2C12 surfactant is higher than DTAB surfactant. 相似文献
33.
Ranjana Yadav 《European Polymer Journal》2007,43(8):3531-3537
Models capable of predicting the maximum extent of conversion (p) of cardanol-based novolac-type phenolic resin, have been developed using response surface methodology to determine the optimum reaction conditions. Three-dimensional response surface and their contour plot were drawn. The maximum extent of conversion (98.93%) was predicted when the cardanol was condensed with formaldehyde (molar ratio 1:0.652) at 119.84 °C for a time period of 3 h with the catalyst (e.g., citric acid) concentration of 1.988% of total volume of cardanol and formaldehyde. The pH of the reaction mixture was maintained at 3.0. These predicted values for optimum process conditions were in good agreement with experimental data. 相似文献
34.
The monoclinic modification of terbium oxide hydroxide, TbOOH, was prepared using hydrothermal technique. The crystal structure was investigated by three-dimensional single-crystal X-ray analysis and was refined to a conventional R-value of 8.1%. The space group is , No. 11, with a = 6.04 Å, b = 3.69 Å, c = 4.33 Å, and β = 109.0°. The terbium atom is seven coordinated with oxygen atoms, and the structure is not hydrogen bonded.The compound is antiferromagnetic with a Néel temperature of 10°K. Neutron diffraction powder patterns were measured at 300°K and 4.2°K. The magnetic super lattice reflections were indexed on the basis of a monoclinic unit cell with the dimensions aM = 2a, bM = b, cM = c, and βM = β, where a, b, c, and β are the dimensions of the chemical unit cell. The structure contains two independent magnetic atoms. A nonclinear antiferromagnetic arrangement of the spins describes the magnetic structure. The spin at one atom has an angle of 43° with the ac plane and the projection of the spin on the ac plane has an angle of 59° with the a axis. The spin on the other atom has an angle of ?43° with the ac plane, the projection having the same angle of 59° with the a axis. 相似文献
35.
36.
Anna Worobiec Lucyna Samek Zoya Spolnik Velichka Kontozova Elzbieta Stefaniak René Van Grieken 《Mikrochimica acta》2006,156(3-4):253-261
The St. Michael Archangel’s Church in Szalowa, Poland, was selected for closer investigation with respect to the indoor/outdoor
air exchange and its influence on the air quality and work arts preservation. Chemical composition, size and abundance of
particulate matter and concentration of gases NO2, SO2, O3 inside and outside the church were determined. To study seasonal variation of the weather condition (temperature, inversion
level, wind direction) and the influence of seasonal sources of the air pollution (like heating of the nearby houses), samples
were collected in winter and summer time. It was stated that suspended particulate matter inside the wooden church has in
general an outdoor source. Several groups of particles were distinguished such as the organic ones, soil dust, nitrates and
sulphates. In case of organic and soil dust particles, the concentration inside was higher than outside. From the results,
in comparison to literature data, one can conclude that accumulation of particulate suspended matter in the church is more
intense than in other types of buildings. Gaseous pollutants were detected but their concentration was negligible. 相似文献
37.
38.
Interfacial layers have been widely applied to study the formation and stability of emulsion-based systems. However, the application of isolated interfaces to address digestibility of emulsions is often limited because of the complexity of experimental methods and results. This review summarizes the latest developments in analytical methods and literature data on effects of digestion on interfacial layers. Particular emphasis is given to understand the changes on interfacial magnitudes during oral, gastric, and duodenal digestion, either applied separately or sequentially. Limitations of interfacial aspects and key factors that influence emulsion microstructure in bulk and lipid digestion are identified. Understanding the behavior of interfacial layers upon gastrointestinal digestion promotes an accurate tracking of the physiological fate of emulsions. 相似文献
39.
M. Paluch 《Colloid and polymer science》1998,276(7):648-652
The results of experimental studies of the adsorption at the solution/air interface from an aqueous mixture: 2,4,6-trimethylphenol–2,4,6-trichlorophenol
are presented. The surface properties of the above-mentioned mixture were studied by surface potential and surface tension
measurements. These measurements were carried out as a function of the concentration of 2,4,6-trimethylphenol aqueous solution
at a constant concentration of 2,4,6-trichlorophenol.
Using the results obtained and based on the Gibbs equation, Helmholtz formula and Motomura’s method the relative surface excesses
of adsorbed substances, effective dipole moments, surface molar fractions of solutes and miscibility of adsorbed films were
determined.
Received: 7 November 1997 Accepted: 26 February 1998 相似文献
40.
A. Račkauskas 《Acta Appl Math》1995,38(1):109-129