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In this work, the fluorescence of FLEET (femtosecond laser electron excited tagging) was enhanced by two color femtosecond laser. the intensity of FLEET was increased about 20% with two laser pulses that were 400 μJ/pulse at 266 nm and 3 mJ/pulse at 800 nm, and the results indicated that there was nearly no influence on lifetime and wavelength of fluorescence from FLEET. This result provides many
Recent studies suggest that concrete creep may be further exacerbated by climate change. However, up to now this effect has not been quantified in literature. The current study addresses this gap and presents a probabilistic approach for quantitatively assessing this effect. For this purpose, five different stochastic creep models (i.e. Model Code 1999, Model Code 2010, B3, B4, and B4s models) are
Today, in developing countries, the low surface water distribution efficiency and the lack of supplying water needs of farmers by surface water resources are compensated by excessive aquifer water withdrawal. This mismanagement has caused a sharp drop in the groundwater level in many countries. On the other hand, climate change and drought have intensified the pressure on water resources. This stu
In view of climate change, increasing soil salinity is expected worldwide. It is therefore important to improve prediction ability of plant salinity effects. For this purpose, brackish/saline irrigation water from two areas in central and coastal Tunisia was sampled. The water samples were classified as C3 (EC: 2.01–2.24 dS m−1) and C4 (EC: 3.46–7.00 dS m−1), indicating that the water was question
During the last two decades, applications of nonlinear dynamic and chaos theories to hydrologic systems and processes have been on the rise. Early applications of these theories focused mainly on the investigation and prediction of chaos in rainfall and river flow dynamics. Subsequent years witnessed their applications for other purposes (e.g. data disaggregation, missing data estimation, reconstr
In the present study, we apply deterministic chaos theory to investigate nonlinear dynamics in monthly precipitation at Mokpo, Korea, after wavelet decomposition. The wavelet transform is used not only for removal of noise but also for extraction of low and high frequency components in the data, representing low-dimensional dynamics. In order to determine an appropriate decomposition level for the
Common irrigation procedures in many parts of the world involve flood irrigation. Observations during recent years have, however, indicated that preferential flow may be an important phenomenon that could affect the outcome of both irrigation and fertilizer application for this irrigation type. To analyze and visualize solute transport by preferential flow mechanisms, field experiments were carrie
Cross-correlation structures based on daily rainfall data recorded during a period of 5 years at 67 stations throughout Tunisia are used to examine spatial rainfall variability. Basic properties of the correlation-distance function such as cumulating period, exclusion versus inclusion of dry periods, and data volume are analysed. Analysis of the correlation patterns for each month shows that two p
The relative effect of combined sewer overflow (CSO) discharge into receiving waters has increased during the last decades due to improved efficiency at treatment plants. In association with the rapid urbanization in the sixties and early seventies, new areas were connected to old sewer networks with limited capacity, leading to an increase in overflow volumes and, thus to an increase in pollution
In this thesis, a microfluidics platform with high-speed imaging system was built to investigate gas-liquid flow in single microchannel and interfacial instability in porous media with microchannel network:The mass transfer of slug flow in the rectangular and square microchannels was experimentally studied by using water as liquid phase and CO2 as gas phase. Depending on flow rates, flow patterns
