Zhang C.,CAS Research Center for Eco Environmental Sciences |
Zhang C.,University of Chinese Academy of Sciences |
Shan B.,CAS Research Center for Eco Environmental Sciences |
Shan B.,University of Chinese Academy of Sciences |
And 5 more authors.
Ecotoxicology and Environmental Safety | Year: 2017
Heavy metal (Cr, Cu, Ni, Pb, and Zn) pollution and the risks posed by the heavy metals in riverine sediments in a mountainous urban-belt area (MB), a mountain–plain urban-belt area (MPB), and a plain urban-belt area (PB) in the Haihe Basin, China, were assessed. The enrichment factors indicated that the sediments were more polluted with Cu and Zn than with the other metals, especially in the MPB. The sediments in the MPB were strongly affected by Cu and Zn inputs from anthropogenic sources. The risk assessment codes and individual contamination factors showed that Zn was mobile and posed ecological risks, the exchangeable fractions being 21.1%, 21.2%, and 19.2% of the total Zn concentrations in the samples from the MB, MPB, and PB, respectively. Cr, Cu, and Zn in the sediments from the MPB were potentially highly bioavailable because the non-residual fractions were 56.2%, 54.9%, and 56.5%, respectively, of the total concentrations. The potential risks posed by the heavy metals (determined from the chemical fractions of the heavy metals) in the different areas generally decreased in the order MPB > MB > PB. Pictorial representation of cluster analysis results showed that urbanization development level could cause Cr and Zn pollution in the urban riverine sediments to become more severe. © 2017 Elsevier Inc.
Zhang J.,Shanghai JiaoTong University |
Zhang J.,Tianjin Hydraulic Research Institute |
Shen Z.,Shanghai JiaoTong University |
Shan W.,Hebei University |
And 2 more authors.
Journal of Hazardous Materials | Year: 2011
An inorganic/organic hybrid adsorbent for phosphate adsorption was synthesized by introducing lanthanum (La) onto diamino modified MCM-41. The adsorbent was characterized by XRD, SEM, BET, TGA, and FTIR spectroscopy. A series of batch tests were conducted to investigate the influence of contact time, initial phosphate concentration, pH of the solution, and competitive ions on the phosphate adsorption capacity. The Langmuir and Freundlich models were used to simulate the sorption equilibrium, and the results indicated that the Langmuir model fitted the experiment data better than the Freundlich model. The maximum adsorption capacity calculated from the Langmuir model is 54.3mg/g. For kinetic study, phosphate adsorption followed the pseudo-second-order equation well with a correlation coefficient greater than 0.99. Optimum pH value for the removal of phosphate was between 3.0 and 7.0. The presence of Cl- and NO3 - has neglectable influence on the phosphate adsorption. F-and SO4 2- have negative effects on the adsorption of phosphate. Phosphate on the spent adsorbent can be almost released by 0.01M NaOH solution in 12min. © 2010 Elsevier B.V.
Li J.,China Agricultural University |
Zhao S.,Tianjin Hydraulic Research Institute
Procedia Engineering | Year: 2012
In order to provide some useful lessons to basin water resources management practice, this paper summarized the successful experience of the two modes of basin water resources management in the United States; one is the mode of the bureau of river basin water resources management represented in Tennessee, and the other is the mode of the committee of river basin water resources management represented in Delaware. The result shows that the improvement in legislation and management and coordination capacity and the increase in multi-stakeholder involvement is the key issue in the water resources management. © 2012 Published by Elsevier Ltd.
Sheng J.-C.,Hohai University |
Bai K.-H.,Hohai University |
Yang X.,Hohai University |
Zheng Z.-W.,Hohai University |
And 3 more authors.
Yantu Lixue/Rock and Soil Mechanics | Year: 2015
For thorough research of the anti-seepage problem in terms of seepage flux and seepage stability due to the geosynthetic clay liner(GCL) defects, the seepage physical test method for the simulation of GCL with defects in dam anti-seepage hydraulic projects is established by means of developing the seepage experimental apparatus consisting of pressure control system and model test system. Factors which affect the joint impermeability of dam soil and GCL with defects are preliminarily discussed according to the seepage test of GCL with different defect conditions. The results show that the hole-defect's size can be more sensitive to the impact of overall permeability of GCL with defects and soil than the defect rate. The main sensitive factors for defect's healing capacity include hole-defect's diameter and GCL specifications (material's own performance). Therefore, two following points should be considered in the projects: (1) the hole-defect's diameter should be less than 0.5 cm in the projects, the ones larger should be repaired; (2) make sure the GCL interface is smooth and flat in case that the local defect rate becomes more than 0.5%. ©, 2015, Academia Sinica. All right reserved.
Li Q.,Hohai University |
Bai X.,Tianjin Hydraulic Research Institute |
Lu G.,Hohai University |
Zou Z.,Changjiang River Scientific Research Institute |
Cai T.,Hohai University
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2011
With population increase and economic growth, the flow regime of the Yangtze River has been altered to some extent by human activities, and particularly by dam construction. Dam-induced alterations in the flow regime will unavoidably influence water allocation among different water uses and instream ecological water requirements may not be satisfied. To assess the impacts of the Three Gorges reservoir operation on the downstream minimum instream ecological water requirements, this paper selected this reservoir and the Yichang hydrological station below the reservoir as case study sites. The reservoir outflows of two water storage schemes were simulated using the long-term time series of daily discharge data, and a satisfaction factor for the downstream minimum ecological flow was computed. This work would provide references for the integrated management of the river's water resources and the assessment of dam-induced impacts on the river's ecosystem health. © Copyright.
Liu Z.,Tianjin Chengjian University |
Cui T.,Tianjin Chengjian University |
Dong L.,Tianjin Hydraulic Research Institute |
Zhang J.,Tianjin Chengjian University |
And 3 more authors.
Materials Express | Year: 2014
One-dimensional TiO2nanowires were fabricated on synthetic zeolite by simple sol–gel and hydrothermal alkali melting synthesis method in order to maximize the specific surface area and photocatalytic performance as well as the retrievability. Effect of reaction time, pH and calcining temperature on structure and photocatalytic activity of the composite photocatalysts were discussed. The decolouration of methylene blue dye in water can rapidly reach to 90% with as-synthetised one-dimensional TiO2nanowires/synthetic zeolite composite after 60 min under the irradiation of UV light, indicating the potential application of as-obtained photocatalysts in wastewater treatment. © 2014 by American Scientific Publishers. All rights reserved.
Yu B.,Dalian University of Technology |
Liang G.,Dalian University of Technology |
He B.,Dalian University of Technology |
Dong L.,Tianjin Hydraulic Research Institute |
Zhou H.,Dalian University of Technology
Shuikexue Jinzhan/Advances in Water Science | Year: 2015
Joint operation of multiple water sources plays a significant role in alleviating the conflict between urban water supply and demand. Firstly, to achieve the effective distribution of various urban water sources, an optimization model based on the network topology of “Source-Plant-User” urban water supply system is proposed. The objectives of this model include social benefit and total water supply cost, subject to the capacity of water sources, water pipes and water plants, and the water demand of users. Secondly, NSGA-II algorithm is applied to solve the model, based on which the optimal condition for the equilibrium solution is obtained. Thirdly, as a case study, the water-supply system in Tianjin city is a complex multi-source water-supply system after the Mid-route of South-to-North Water Diversion Project (SNWDP) begins to divert water to Tianjin. The optimization results show that this model could successfully provide corresponding reasonable allocation solutions compromising social benefit and water supply cost under different wetness and dryness probabilities at water sources. And the causes of water shortage and the existing design deficiency in the urban water supply network could be reflected through result analysis. For example, the water supply capacity (1 473 million m3) of the worst condition could satisfy the water demand of Tianjin (1 377 million m3); whereas, the water shortage of recommended solution, which balances the social benefits and water shortage, is 244 million m3 with water supply cost of 3 260 million yuan due to the capacity restriction of the pipelines under the specific water supply rule. Above all, this model is feasible to a certain extent and provides technical support for ensuring urban water-supply security of Tianjin city. © 2015, Science Press. All right reserved.
Chang S.,Tianjin Hydraulic Research Institute |
Wu T.,Tianjin Hydraulic Research Institute |
Zhao J.,Tianjin University
Chinese Journal of Environmental Engineering | Year: 2016
The purification effects on Beidagang Reservoir water by planting Myriophyllum, Ceratophyllum and Potamogeton labyrinth were studied, according to its current characteristics of single submerged macrophyte and poor water purification capacity. It was indicated that Myriophyllum could provide carriers for aquatic microorganisms, which could help the removal of nitrogen, phosphorus and other nutrients, and also could prevent the resuspension of suspended material and improve the clarity of the water. Purification ability, removal efficiency and the water environment were improved when the submerged groups was planted together. Myriophyllum could be inhibited by planting together whith Ceratophyllum and Potamogeton. MATLAB software was also used for comprehensive analysis, which indicated that the best purification ability could be achieved when Myriophyllum, Ceratophyllum and Potamogeton labyrinth group was planted. It was mean that Ceratophyllum and Potamogeton labyrinth could be introduced to Beidagang Reservoir based on the existing situation, which would be favourable to improve its water ecological environment and self-purification capacity. © 2016, Science Press. All right reserved.
Liu B.,Tianjin Hydraulic Research Institute |
Liu X.,Tianjin Hydraulic Research Institute |
Yang J.,Tianjin Hydraulic Research Institute |
Garman D.E.J.,University of Wisconsin - Milwaukee |
And 2 more authors.
Water Science and Technology | Year: 2012
Phosphorus (P) is often the limiting nutrient for algal growth, and P in sediments can be released under suitable conditions. To control P release, in-situ control technology with lanthanum (La) modified bentonite clay (Phoslock®) was proposed and its effectiveness was tested and evaluated both in laboratory and field trials. The results of static and dynamic simulation experiments under different environmental conditions showed that with the application rate of Phoslock® at 0.5 kg/m 2, the orthophosphate (PO4-P) concentration of the overlying water decreased to a low level (≤0.02 mg/L) within 10 days. Even under anaerobic and high pH (pH = 9.0) conditions, the phosphate release suppression efficiency reached 98.3%, and the P-release rate was -8.20 mg/m 2 d (negative value indicates P adsorption by Phoslock®). The monitoring data of the field sediments rehabilitation project were consistent with the results achieved in laboratory experiments, thus showing that the application of Phoslock® could inhibit the internal P release effectively. © IWA Publishing 2012.
PubMed | Tianjin Hydraulic Research Institute
Type: Evaluation Studies | Journal: Water science and technology : a journal of the International Association on Water Pollution Research | Year: 2012
Phosphorus (P) is often the limiting nutrient for algal growth, and P in sediments can be released under suitable conditions. To control P release, in-situ control technology with lanthanum (La) modified bentonite clay (Phoslock()) was proposed and its effectiveness was tested and evaluated both in laboratory and field trials. The results of static and dynamic simulation experiments under different environmental conditions showed that with the application rate of Phoslock() at 0.5 kg/m(2), the orthophosphate (PO(4)-P) concentration of the overlying water decreased to a low level (0.02 mg/L) within 10 days. Even under anaerobic and high pH (pH = 9.0) conditions, the phosphate release suppression efficiency reached 98.3%, and the P-release rate was -8.20 mg/m(2) d (negative value indicates P adsorption by Phoslock()). The monitoring data of the field sediments rehabilitation project were consistent with the results achieved in laboratory experiments, thus showing that the application of Phoslock() could inhibit the internal P release effectively.