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21.
P. T. Tsilingiris 《国际能源研究杂志》1991,15(9):723-730
The paper describes the calculation of the beam solar radiation transmission across the uniform salinity upper convecting zone (UCZ) and the salinity stratified gradient zone (GZ), when the extinction coefficient is not only wavelength but also salinity-concentration dependent, assuming that the effect of scattering to be negligible. The results are useful in determining the effects of dissolved salt ions on pure water transmission, at least according to the existing measured data in the literature. 相似文献
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Two different generators for ozone were tested, a traditional electrical discharge generator and a generator based upon UV–irradiation of air at 150–180 nm. It was demonstrated that the traditional generator gave slightly higher reductions in levels of color for equivalent ozone dosages. Both gases affected the molecular weight distribution in the way that the bigger molecules were broken down to smaller ones. No significant difference between the molecular weight reduction efficiency of the gases was found. 相似文献
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Molecular dynamics simulation using a universal force field has been employed to determine the diffusion coefficients of O2 and Na2SO4 vapor into B2O3 and SiC from 700 K to 1273 K, respectively. Einstein diffusion was observed in a 250~300 ps simulation. 相似文献
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Javier Lara-Romero Rafael Maya-Yescas José Luis Rico-Cerda José Luis Rivera-Rojas Fernando Chiñas Castillo Matey Kaltchev 《Thin solid films》2006,496(2):463-468
The thermal decomposition of model extreme-pressure lubricant additives on clean iron was studied in ultrahigh vacuum conditions using molecular beam strategies. Methylene chloride and chloroform react to deposit a solid film consisting of FeCl2 and carbon, and evolve only hydrogen into the gas phase. No gas-phase products and less carbon on the surface are detected in the case of carbon tetrachloride. Dimethyl and diethyl disulfide react on clean iron to deposit a saturated sulfur plus carbon layer at low temperatures (∼600 K) and an iron sulfide film onto a Fe + C underlayer at higher temperatures (∼950 K). Methane is the only gas-phase product when dimethyl disulfide reacts with iron. Ethylene and hydrogen are detected when diethyl disulfide is used. 相似文献
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本文综述了国外碳纤维、陶瓷、聚芳酰胺、超高分子量聚乙烯、液晶聚合物纤维的发展现状,包括它们的生产能力、消费情况、性能特点,主要生产国和生产公司、产品牌号以及应用领域等,并指出了其生产进展和发展动向。 相似文献
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Recent advances in the realization of individual molecular‐scale devices [1,2] highlight the integration of individual devices into large‐scale functional circuits as the major challenge. DNA‐programmed assembly is a promising avenue in that direction due to the large amount of information that can be coded into the molecules and the ability to translate that information into physical constructs [3]. Large‐scale DNA‐templated electronics require, however, complex manipulation of double‐stranded DNA (dsDNA) molecules, as well as patterning of the electrical properties instilled to them by, e.g., metallization. To that end, sequence‐specific molecular lithography on single DNA molecules has been developed [4]. This was achieved by harnessing the exquisite homologous recombination process of the RecA protein. Sequence‐specific patterning of the metal coating of DNA molecules, localization of arbitrary labeled molecular objects at any desired dsDNA address without prior modifications, and generation of molecularly accurate stable dsDNA‐dsDNA junctions are demonstrated. The information encoded in the DNA molecules directs the lithographic process in analogy to the masks used in conventional microelectronics. The RecA protein provides the assembling capabilities, as well as the resist function. 相似文献