作者机构：
[Deng, B.; Jiang, C. B.; Zhang, W.] Changsha Univ Sci & Technol, Sch Hydraul & Environm Engn, Changsha 410114, Peoples R China.;[Deng, B.; Jiang, C. B.] Key Lab Water Sediment Sci & Water Disaster Preve, Changsha 410114, Peoples R China.;[Tang, H. S.] CUNY City Coll, Civil Engn Dept, 160 Convent Ave, New York, NY 10031 USA.;[Liu, X. J.] Pearl River Hydraul Res Inst, Guangzhou 510611, Peoples R China.
通讯机构：
[H.S. Tang] C;Civil Engineering Department, The City College of New York, 160 Convent Avenue, New York 10031, United States
关键词：
Bedform;Dam-break bore;Fractal dimension;Hydraulic jump;Sand migration;Swash zone
摘要：
This study makes an experimental study on hydrodynamics and sediment driven by dam-break waves in swash zones of three sandy beaches. The experiment adopts three beaches: a 1:10 uniform-sand beach, a 1:10 non-uniform-sand beach, and a 1:35 non-uniform-sand beach. This paper reports its measurements on swash water depth, morphology, bedload, and migration of sand particles. It also analyzes the hydraulic jump and sandbar, sorting and sedimentology characteristics, and fractal dimension of bedform. The analysis indicates that the uniformness of sand particle sizes plays an important role in hydrodynamic behaviors, bedform evolution, bedload transport, and migration of sand particles. The fractal dimension of beach profiles lies between 1.15 and 1.25 after swash action, despite changes in bed profiles.
摘要：
Understanding tsunami-induced scour at a pile breakwater is important for the foundation safety of this type of coastal defense structures. A series of wave-flume tests were performed for G∕D=0.11, with G being the gap size and D the pile diameter, to study the characteristics of the solitary-wave-induced local scour around a pile breakwater, including the scour-hole depth, scour-hole length, deposition sandbar height and the scoured volume. It was found that the jet flow through the gaps between piles caused the local scour around individual piles. A more or less two-dimensional deposition sandbar was found on the down-wave side of the pile breakwater in the later stage of the scour process. A new empirical equation was introduced to approximate the evolution of the depth of the scour hole induced by a series of solitary waves. The equation was verified by existing data reported in the literature for G∕D=0.39 and the new data reported in this study. Effects of the distance between piles on the characteristics of the local scour were discussed by comparing the results for G∕D=0.11 and 0.39. The comparison showed that the scour-hole depth and height of the sandbar for G∕D=0.11 were all noticeably larger than the corresponding values for G∕D=0.39.
摘要：
Increased chloride concentration can cause salinization, which has become a serious and widespread environmental problem nowadays. This review aims at providing comprehensive and state-of-the-art knowledge and insights of technologies for chloride removal. Mechanisms for chloride removal mainly include chemical precipitation, adsorption, oxidation and membrane separation. In chemical precipitation, chloride removal by forming CuCl, AgCl, BiOCl and Friedel's salt. Adsorbents used in chloride removal mainly include ion exchangers, bimetal oxides and carbon-based electrodes. Oxidation for chloride removal contains ozone-based, electrochemical and sulfate radical-based oxidation. Membrane separation for chloride removal consists of diffusion dialysis, nanofiltration, reverse osmosis and electrodialysis. In this review, we specifically proposed the factors that affect chloride removal process and the corresponding strategies for improving removal efficiency. In the last section, the remaining challenges of method explorations and material developments were stated to provide guidelines for future development of chloride removal technologies.
通讯机构：
[Minghua Zhou] K;Key Laboratory of Pollution Process and Environmental Criteria, Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
关键词：
TiO2 nanotubes;Co-doped boron and cobalt;Flow-through;Electrochemical activation of persulfate;Carbamazepine
摘要：
Degradation of carbamazepine (CBZ) was first conducted by electrochemical activation of persulfate (PS) in flow-through system using boron and cobalt co-doped TiO2 nanotubes (B, Co-TNT) as the anode and carbon felt (CF) as the cathode, achieving a higher removal efficiency than that in beaker mode ascribed to the higher PS decomposition for center dot OH production. Different operating parameters including applied current, initial pH, PS concentration and flow rate were explored, supporting that high current, acidic condition, lofty PS concentration and flow rate were beneficial for the removal of CBZ. The mechanisms of CBZ degradation by electrochemical activation of persulfate in flow-through system were the comprehensive effect of center dot OH, SO4 center dot- and O-1(2), and the possible CBZ degradation pathway was proposed. In summary, B, Co-TNT anode coupled with CF cathode in flow-through system by electrochemical activation of persulfate was an effective method for contaminants degradation.
摘要：
Oily sludge (OS), a hazardous waste produced in a large amount in petroleum industries, has raised great interest in research, and thermal treatment method such as pyrolysis is promising to achieve the goal. This research studied the pyrolysis behavior during co-pyrolysis of OS and high-density polyethylene (HDPE, plastic waste model component) with different blend ratios. The changes of functional groups against pyrolysis temperature were detected via in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The interactive effect between the two feedstocks during co-pyrolysis was analyzed via thermogravimetric analysis (TGA). The DRIFTS showed that the pyrolysis of HDPE can provide abundant center dot CH(3 )free radicals which may accelerate the pyrolysis of OS. The disparities between theoretical and experimental thermogravimetric/derivative thermogravimetry (TG/DTG) curves of mixtures indicated a synergistic interaction during co-pyrolysis. Besides, the activation energy of co-pyrolysis was obtained based on kinetic analysis, which showed that the average activation energy followed the trend of O3H1 < OS < O1H1 < HDPE < O1H3. In addition, two artificial neural network (ANN) models, namely ANN model I with training and testing R2 of 0.99 (for prediction of interactive effect) and ANN model II with training and testing R2 of 0.92 (for prediction of activation energy), were established and validated by comparing with the experimental data, which showed satisfied credibility. Ultimately, the two ANN models were used to reversely guide and optimize experiment design for the highest synergistic effect and the minimum activation energy. This study offers a new insight and strategy to aid pyrolysis experimental studies.
通讯机构：
[Shiquan Sun] K;Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province/School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China
摘要：
With the higher requirements of energy conservation and carbon emission reduction, wastewater treatment process is facing unprecedented challenges. Microbial electrochemical technologies (METs) have been gradually applied to wastewater treatment due to their unique ability to convert organic waste into green energy and recover useful byproducts. Here, we comprehensively summarize the recent advances in the following areas: (1) the basis of METs containing different types of electroactive microorganisms and the main extracellular electron transfer (EET) forms; (2) Key factors that affect electroactive biofilm formation and MET performance, such as the electrode potential, external resistance, dissolved oxygen, microbial inoculation source, chemical signaling, electrode materials, and substrates for wastewater treatment processes; (3) The application of METs in energy recovery synchronized with wastewater treatment, high value-added by-product recovery, heavy metal reduc-tion, biological early warning and nutrient recovery. Finally, we summarize and discuss the future development directions of METs.
