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The design of a liquid/liquid contact apparatus necessitates the knowledge of fluid dynamics and mass transfer in the dispersion. Prediction of process parameters is challenging due to swarm and interfacial effects. Single drop investigations are suitable to enable a sophisticated dimensioning based on few simple experiments combined with published theories and correlations. In the first part of this article, the fundamentals of fluid dynamics and mass transfer in absence of interfacial effects were explained. Here, an overview of relevant interfacial phenomena and the influence of different substances typically occurring in technical applications as impurities or accompanying components is given. 相似文献
3.
为改进模型对高寒地区融雪径流模拟不足的缺陷,将融雪模块耦合到传统 abcd 模型。利用 1980—2018 年
逐月实测的径流数据和通过 AnuSpline 方法插值的格网气象要素,驱动改进后的abcd 模型,分析三江源生态保护
措施实施前后(1980—1999 年和 2000—2018 年)黄河源区径流的动态变化,并量化关键气象因素与人类活动对
径流变化的影响程度,即相对贡献。结果表明:耦合融雪模块的 abcd-snow 模型完善了高寒地区水文过程的模拟,
提高对径流的模拟性能,在黄河源区表现出较好的适用性;整个研究时段黄河源区的实测径流呈不显著减少趋势
(?0.80?mm/a,p>0.05),但 2000 年前径流则呈现显著下降趋势(?4.12?mm/a,p<0.05),2000 年后径流则呈显著增加
趋势(3.16?mm/a,p<0.05);?归因分析表明气候变化是源区径流变化的主导因素。2000 年前,气候变化对径流减少
的相对贡献率为 62.8%,人类活动对径流的贡献为 37.2%;2000 年后,气候变化对径流增加的贡献率达到 120.0?%,
人类活动对径流的贡献为?20.0%。其中:降水的变化是决定径流变化主导因素;其他气候因素的相对贡献较小;
以人类活动为主的生态恢复可显著降低河川径流。本研究有助于理解气候变化和下垫面变化对黄河源区水资源
变化的系统驱动机理,并为流域水资源合理配置提供科学参考依据。 相似文献
4.
Scientometrics - Computer-assisted methods and tools can help researchers automate the coding process of literature reviews and accelerate the literature review process. However, existing... 相似文献
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Altair T. Contreras Jaimes Araceli de Pablos-Martín Katrin Hurle Juliana Martins de Souza e Silva Lutz Berthold Thomas Kittel Aldo R. Boccaccini Delia S. Brauer 《Journal of the European Ceramic Society》2021,41(9):4958-4969
One key issue influencing a broader application of Bioglass 45S5 in tissue engineering is its inherent crystallization tendency, severely limiting the mechanical strength of 3D porous scaffolds. Despite numerous studies, Bioglass 45S5 crystallization is not yet fully understood with regard to the mechanisms involved or morphology of the crystal phases forming. Here we show how two cutting-edge imaging techniques, state-of-the-art transmission electron microscopy (TEM) with image correction including energy dispersive X-ray spectroscopy and X-ray nano-computed tomography (nano-CT), allowed us to visualize changes in microstructure from near-nucleation to almost full crystallization in bulk Bioglass 45S5. At early times of heat treatment at 660 °C the formation of phase-separated nano-droplets within the glassy matrix was observed. Later, besides surface crystallization, bulk crystallization of combeite spheres was predominant. The formation of the first combeite spheres, their coarsening with time and finally their merging at near full crystallization were recorded by in situ high-temperature optical microscopy videos. The 3D nature of these spheres was confirmed by nano-CT, while TEM showed that their internal structure was composed of sub-micron grains. X-ray diffraction analysis at early time points showed a much higher crystalline fraction in bulk samples compared to powder samples, highlighting the influence of processing and sample morphology. These results show the importance of using complementary techniques for gaining insight into the crystallization process in the volume. In addition, we show that TEM and nano-CT are suitable characterization techniques to visualize the crystallization even in fast crystallizing systems, such as bioactive glasses. 相似文献
7.
Katarzyna Tokarczyk-Dorociak Jan K. Kazak Haładyj Anna Szymon Szewrański Małgorzata Świąder 《影响评估与项目评价》2019,37(3-4):279-291
The paper presents the results of an evaluation of the effectiveness of SEA obtained as a result of a survey with the participation of stakeholders. In Poland, several hundred SEAs are conducted annually at the local and regional levels and several at the national level. Although the survey demonstrated that SEA is evaluated as effective or quite effective, the respondents pointed to several irregularities in the non-procedural dimension of effectiveness. The main ones in terms of substantive effectiveness are that SEA is rarely used to help develop plans/programmes and procedures are highly politicised. Moreover, low effectiveness in terms of variant assessment and cumulative impacts and nearly non-existent monitoring of the actual effects of implementing plans/programmes influence substantive effectiveness significantly. The respondents pointed to the problem resulting from the fact that plan-makers are unwilling to take into account the SEA recommended changes. They also emphasised that there are certain attempts to put pressure on SEA consultants to make the conclusions less stringent. Respondents indicate that in Poland the costs associated with conducting SEA often outweigh the profits. The research shows that the society is properly informed about SEA, but public involvement is still low. 相似文献
8.
Bahreini Kiavash van der Vegt Wim Westera Wim 《Multimedia Tools and Applications》2019,78(14):18943-18966
Multimedia Tools and Applications - This paper represents our newly developed software for emotion recognition from facial expressions. Besides allowing emotion recognition from image files and... 相似文献
9.
Scientometrics - While bibliometrics are widely used for research evaluation purposes, a common theoretical framework for conceptually understanding, empirically studying, and effectively teaching... 相似文献
10.
Sanaz Salati Frank J. A. van Ruitenbeek Freek D. van der Meer 《International journal of remote sensing》2019,40(13):4934-4954
The persistent natural hydrocarbon seepage in onshore basins challenges observation and exploration technologies, which are required to document and assess these valuable indications of the presence of oil and gas in the subsurface. This paper aims at demonstrating the relationship between the compositional variation of an evaporite cap rock and the types of seeps occurring at the surface. For this purpose, the multispectral Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data was utilized for mapping mineral variations of a petroleum system in the Zagros oil fields. Relative absorption-band depth (RBD), band rationing and the boosted regression trees (BRT) were applied to enhance and classify the mineral composition of evaporite, sandstone, and marly limestone formations. The gas seeps were associated with the areas of gypsum-bearing evaporite cap rock while oil seeps were mostly associated with calcite and clay zones within the cap rock, which was more prone to fracturing during the tectonic activities of the basin. It is suggested that the application of remote sensing in the oil and gas industry could be widened by detection of sleep-induced alteration to assess the efficiency of cap rock and to evaluate the productivity of reservoirs at a regional scale. 相似文献