氙弧灯和荧光紫外灯对面漆漆膜破坏性的比较

依据2项国家标准,分别采用氙弧灯和荧光紫外灯对不同颜色面漆漆膜的破坏性开展试验研究.试验结果显示,2种光源对面漆漆膜破坏性的区别主要表现在失光、色差和粉化方面.从成膜物质和试验条件方面分析试验结果的形成原因,比较2种光源对漆膜破坏的等效性.     

荧光显微分析技术在沥青研究中的应用

对现有沥青的荧光显微分析技术进行了总结,结合本试验室内沥青荧光显微检测案例,探讨了荧光显微镜在改性沥青质量检测、性能辅证等方面具有的直接、形象的使用优势,并提供了在沥青荧光显微镜使用中的某些经验和体会。     

On the relation between organic and inorganic carbon in the Weddell Sea

Carbon cycling in the Weddell Sea was investigated during the ANT X/7 cruise with `FS Polarstern' December 1992–January 1993. Samples were taken on a cross section from Kapp Norvegia to Joinville Island, and on a section from the Larsen Ice Shelf to the northeast. The following quantities were measured: total carbon dioxide (TCO₂), fluorescence from humic substances and total organic carbon. The distribution of TCO₂ was strongly positively correlated to the time elapsed since the various water masses were last ventilated. In general, humic substance fluorescence was positively correlated with TCO₂, with the exception of the productive part of the western Weddell Sea, where the correlation was negative in the surface mixed layer. The increased fluorescence at the surface is suggested to be a result of biological production. The distribution of total organic carbon showed less structure, since this quantity includes a particulate component, which is subject to dispersion processes different from those of the dissolved components TCO₂ and humic substances. The mean total organic carbon concentration below the surface mixed layer was 50 μmol l⁻¹. At some stations, a steep TOC maximum around 2000 m depth was observed. This was interpreted to result from mass sinking of phytoplankton blooms. Total organic carbon had a maximum in surface water, and at some stations also a second subsurface maximum. In the Warm Deep Water (WDW), TCO₂ and fluorescence had their maximum values, while total organic carbon tended to be low. In low productivity surface water in the eastern part of the Kapp Norvegia–Joinville Island section, the lowest flourescence was found. Surface water is eventually formed from Warm Deep Water, which had the highest fluorescence values, and therefore it is concluded that humic substances were removed in situ from surface water. In the central area of the Weddell Sea, TCO₂ and fluorescence showed the highest Warm Deep Water maxima, while total organic carbon was low. The Warm Deep Water in this area is part of the so-called Central Intermediate Water which circulates for a long time within the Weddell Gyre. Reduced total organic carbon, which coincides with the most pronounced Central Intermediate Water characteristics, and high TCO₂ can thus both be accounted for by continued degradation of organic matter in this water mass. The associated fluorescence maximum implies that humic substances are also produced during mineralisation. Recently formed bottom water, by contrast, could be seen as patches of low TCO₂, low fluorescence and high total organic carbon along the western slope of the Weddell Sea.