Continuous extreme ultraviolet (EUV) emission intensity from a laser-produced plasma in the wavelength between 40 and 200 nm for a copper–tungsten alloy target was observed to be 1.3 times higher than that for a tungsten target. Using the alloy target, low-opacity regions of one material were filled with high-opacity regions of another material. This opacity effect resulted in the increase of a calculated Rosseland mean opacity compared with either of the constituents, which may explain the increase of the EUV emission intensity. 相似文献
AbstractFluorescence characteristics of uric acid in Red Sea bream (Pagrus major) eye fluid was explored as a potential rapid and simple assessment for fish freshness. To investigate this, eye fluid samples were collected during storage at 22?±?2?°C for standard uric acid measurements by high-performance liquid chromatography at 12?h intervals up until 36?h storage. Simultaneously, uric acid fluorescence spectroscopy measurements by fluorophotometer at 3?h intervals up until 36?h storage were made. High-performance liquid chromatography results showed the concentration of uric acid increased with storage time in the Red Sea bream eye fluid; changes similar to those observed in Japanese dace eye fluid, only differing in concentration and rate of accumulation. The fluorescence signals of uric acid in Red Sea bream eye fluid increased with storage time, which the high-performance liquid chromatography results confirmed. To further explore this, uric acid fluorescence signals were plotted against a standard fish freshness indicator “K value”, which is calculated from the concentration of adenosine triphosphate and its breakdown products using paper electrophoresis method. A good exponential relationship between these two parameters (determination coefficient of 0.94). A high linear correlation between the predicted K value from the uric acid fluorescence signals and the measured K value (determination coefficient of 0.94 and root mean square error of prediction of 6.37%) indicate uric acid fluorescence characteristics in fish eye fluid has a high potential to be employed as a new, fast and simple method to assess fish freshness. 相似文献
Porous surface patterns are used in a wide variety of practical applications. Honeycomb‐patterned porous polymer films are good templates for preparing porous surfaces due to their simple fabrication and the arrangement of pores on the surface. Catechol groups include in adhesive protein of mussels have attracted much attention due to their highly and substrate‐independent adhesive properties. In this paper, highly and substrate‐independent adhesive honeycomb‐patterned porous polymer films are prepared by using amphiphilic copolymer having catechol moieties. Furthermore, porous surface patterns are transferred on various organic or inorganic substrates by wet etching with using adhesive honeycomb films as templates.
The geometry and characteristic length of diffraction and re-initiation during a two-dimensional detonation propagation were revealed by visualization. C2H4 + 3O2 (unstable), 2C2H2 + 5O2 + 7Ar (stable) and 2C2H2 + 5O2 + 21Ar (stable) were used as the test mixtures. Experiments were performed over the deviation angle range from 30° to 150° and the initial pressure range from 15.8 to 102.3 kPa. By self-emitting photography, we confirmed that the geometry and the characteristic length of diffraction are not different among test gases, with the exception of the fan-like structure of re-initiation that occurred regardless of whether the mixture was unstable or stable. We conducted a compensative experiment by changing the deviation angle and initial pressure, and summarized the detonation diffraction by shadowgraph. At deviation angles larger than 60°, we measured the distances from the vertex of the channel corner to the point where the transverse detonation wave reflected on the under wall (= wall reflection distance) and confirmed that wall reflection distances are approximately in the range of 10–15 times the cell width, whether the mixture is unstable or stable. 相似文献
Understanding the mechanism of the oxygen reduction reaction over nonprecious metal catalysts is important for green and sustainable electrochemical energy conversion. This article presents our recent progress in kinetic studies using rotating ring-disk electrodes. We have established a mathematically and experimentally modified rotating ring-disk electrode approach to calculate the corresponding kinetic rate constants of the 4-e reduction of O2 to H2O (k1), the 2-e reduction of O2 to H2O2 (k2), and the 2-e reduction of H2O2 to H2O (k3). Furthermore, the overestimation of the 4-e reduction process, which derives from the (2 + 2)-e pathway in the catalyst layer matrix, was corrected by studying the effect of catalyst loading density. The established method has been successfully applied to the oxygen reduction reaction over Fe/N/C and N/C catalysts in acidic and alkaline media. 相似文献