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Wang Y.S.,University of Jinan | Wang Y.S.,Groundwater Technology | Xu Z.H.,University of Jinan
Applied Mechanics and Materials | Year: 2014

The stable isotope compositions of soil water from the profiles at Jinan southern mountain reveal information about the mechanism of soil movement. The stable isotopes in soil water have a wide range from -8.92‰ to -5.95‰ forδ 18O and -50.01‰ to -79.44‰ forδD. The mean isotope values is -7.75‰ forδ 18O and 65.84‰ forδD. The low-δD of shallow (<5cm) soil water is due to the precipitation infiltration. And deep soil water (>5cm) is enrichment, which indicates the soil water is evaporated before recharging. The stable oxygen and hydrogen isotope are plotted near the meteoric water line. The trend line for the relationship between δ18O and δD of soil water is given. © (2014) Trans Tech Publications, Switzerland. Source

Eschenbach W.,Johann Heinrich Von Thunen Institute | Well R.,Johann Heinrich Von Thunen Institute | Walther W.,Groundwater Technology
Biogeosciences | Year: 2015

Knowledge about the spatial variability of in situ denitrification rates (Dr(in situ)) and their relation to the denitrification capacity in nitrate-contaminated aquifers is crucial to predict the development of groundwater quality. Therefore, 28 push-pull 15N tracer tests for the measurement of in situ denitrification rates were conducted in two sandy Pleistocene aquifers in northern Germany.

The 15N analysis of denitrification-derived 15N-labelled N2 and N2O dissolved in water samples collected during the push-pull 15N tracer tests was performed using isotope ratio mass spectrometry (IRMS) in the lab and additionally for some tracer tests online in the field with a quadrupole membrane inlet mass spectrometer (MIMS) in order to test the feasibility of on-site real-time 15N analysis. Aquifer material from the same locations and depths as the push-pull injection points was incubated, and the initial and cumulative denitrification after 1 year of incubation (Dcum(365)) as well as the stock of reduced compounds (SRC) was compared with in situ measurements of denitrification. This was done to derive transfer functions suitable to predict Dcum(365) and SRC from Dr(in situ).

Dr(in situ) ranged from 0 to 51.5 Î1/4g N kgg'1 dg'1. Denitrification rates derived from on-site isotope analysis using MIMS satisfactorily coincided with laboratory analysis by conventional IRMS, thus proving the feasibility of in situ analysis. Dr(in situ) was significantly higher in the sulfidic zone of both aquifers compared to the zone of non-sulfidic aquifer material. Overall, regressions between the Dcum(365) and SRC of the tested aquifer material with Dr(in situ) exhibited only a modest linear correlation for the full data set. However, the predictability of Dcum(365) and SRC from Dr(in situ) data clearly increased for aquifer samples from the zone of NO3g'-bearing groundwater.

In the NO3g'-free aquifer zone, a lag phase of denitrification after NO3g' injections was observed, which confounded the relationship between reactive compounds and in situ denitrification activity. This finding was attributed to adaptation processes in the microbial community after NO3g' injections. It was also demonstrated that the microbial community in the NO3g'-free zone just below the NO3g'-bearing zone can be adapted to denitrification by NO3g injections into wells for an extended period. In situ denitrification rates were 30 to 65 times higher after pre-conditioning with NO3g. Results from this study suggest that such pre-conditioning is crucial for the measurement of Dr(in situ) in deeper aquifer material from the NO3g'-free groundwater zone and thus for the prediction of Dcum(365) and SRC from Dr(in situ). © Author(s) 2015. Source

Xing L.-T.,University of Jinan | Xing L.-T.,Groundwater Technology | Wu Q.,China University of Mining and Technology | Gu Y.-W.,University of Jinan
Meitan Xuebao/Journal of the China Coal Society | Year: 2013

Coal mining in Jurassic coalfields of the arid Northwest area has damaged the local water resources greatly. Basing on the analysis of diachronic changes of the drainage and water balance of Jinjie Coal Mine, the paper gave some explanations of the changes of circulation patterns of groundwater before and after the mining. According to the changing characteristics of the water levels of pore water, fissure water and mixed water of double aquifers before and after mining, it was believed that the variation of the hydraulic properties of the roof aquifer in the mining area is mainly induced by the unified evolution of the transmission and closing property of roof aquifuge during the promoting process of mining face. The variation of the transmission and closing property of roof aquifuge changes the circulation pathways of mine groundwater, and the heavy-water deposits could be formed in the arid area. Also, the paper holds that the prediction method of real-time mine inflow based on variations of roof hydraulic properties will be one of the key issues in the future studies of deposit hydrogeology. Source

Liu B.,University of Jinan | Liu B.,Groundwater Technology | Li Y.,Tianjin University | Ma J.,Chinese Research Academy of Environmental Sciences | And 2 more authors.
Water Science and Technology | Year: 2016

China is suffering from serious water and soil pollution, especially in the North China Plain. This work investigated semi-volatile organic compounds (SVOCs) in surface water, groundwater and soil within a chemical industrial park in Eastern China, for which the volatile organic compound (VOC) results have been previously reported. A total of 20 samples were collected from the field, and analyzed in the laboratory. A 100% detection frequency of SVOCs in samples from this chemical industrial park was observed (same as VOCs). Moreover, the detection frequency of 113 SVOCs in each sample reached 15.93, 12.39 and 20.35% for surface water, groundwater and soil, respectively. The most detected SVOCs in the park included N-containing SVOCs, polycyclic aromatic hydrocarbons, phthalates, organic pesticides and polychlorodiphenyls. The elevated detecting frequencies and concentration levels of SVOCs identified in the groundwater were attributed to the intensive chemical production activities in the park. In addition, the agricultural activities in the area might also have contributed to the SVOCs to the groundwater. The results of VOCs and SVOCs from this and previous studies suggest that the groundwater in this industrial park has been severely contaminated, and the contamination likely spreads beyond the park. Imminent hydrogeological assessments and remedial actions are warranted to eliminate the source and mitigate the potential plume expansion beyond the park boundary. © IWA Publishing 2016. Source

Hao Y.-F.,University of Jinan | Yan L.-G.,University of Jinan | Yan L.-G.,Groundwater Technology | Yu H.-Q.,University of Jinan | And 4 more authors.
Journal of Molecular Liquids | Year: 2014

Hydroxy-aluminum pillared bentonite (Al-Bent) was prepared and characterized in this work, and its dye adsorption capacity was comparatively studied in batch experiments. Results of characterization revealed that because of the intercalation of hydroxy-aluminum polyoxycations, a significant increase of interlayer basal spacing, BET surface area and total pore volume was beneficial to dyes' adsorption. The sodium bentonite had a higher adsorption affinity for Basic Fuchsin (BF) and Basic Green (BG) than Acid Turquoise Blue A (ATBA). After pillaring, the adsorption capacity of the three dyes increased and the rise of pH changed insignificantly with solution from 2 to 8. The pseudo-second-order kinetic model provided the best correlation of the experimental data (R2> 0.99). Henry and Freundlich models both described the adsorption isotherm data well. The adsorption capacity of Al-Bent for the three dyes, especially the basic dyes BF and BG, was high over a wide range of aqueous concentrations and followed the order of BG > BF > ATBA. © 2014 Published by Elsevier B.V. Source

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