Publications by authors named "Dan Zhi"

21 Publications

  • Page 1 of 1

Microplastics and environmental pollutants: Key interaction and toxicology in aquatic and soil environments.

J Hazard Mater 2021 Aug 8;422:126843. Epub 2021 Aug 8.

Pyrolysis Technology Research Group, Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia.

Nowadays, a growing number of microplastics are released into the environment due to the extensive use and inappropriate management of plastic products. With the increasing body of evidence about the pollution and hazards of microplastics, microplastics have drawn major attention from governments and the scientific community. As a kind of emerging and persistent environmental pollutants, microplastics have recently been detected on a variety of substrates in the world. Therefore, this paper reviews the recent progress in identifying the sources of microplastics in soil, water, and atmosphere and describing the transport and fate of microplastics in the terrestrial, aquatic and atmospheric ecosystems for revealing the circulation of microplastics in the ecosystem. In addition, considering the persistence of microplastics, this study elucidates the interactions of microplastics with other pollutants in the environment (i.e., organic pollutants, heavy metals) with emphasis on toxicity and accumulation, providing a novel insight into the ecological risks of microplastics in the environment. The negative impacts of microplastics on organisms and environmental health are also reviewed to reveal the environmental hazards of microplastics. The knowledge gaps and key research priorities of microplastics are identified to better understand and mitigate the environmental risks of microplastics.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126843DOI Listing
August 2021

Sustainable biochar/MgFeO adsorbent for levofloxacin removal: Adsorption performances and mechanisms.

Bioresour Technol 2021 Nov 31;340:125698. Epub 2021 Jul 31.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China. Electronic address:

The limitation of low efficiency and complicated separation after adsorption make the practical application of biochar a huge challenge. Here, one pomelo peel-derived magnetic biochar composite, biochar supported MgFeO (BMF) was fabricated and adopted for Levofloxacin (LFX) adsorption. Adsorption behaviors and mechanisms were investigated by characterization analysis, batch experiments, and data modeling. Results indicated that adsorption could be strikingly influenced by pyrolysis temperature. Adsorption kinetic was well fitted by pseudo-second-order model. Adsorption isotherm was best fitted with Freundlich model. The maximum adsorption capacity was 115 mg g. Moreover, hydrophobic effect played a limited contribution according to dual-mode model analysis. LFX adsorption was spontaneous and endothermic. Adsorption mechanisms were ascribed to electrostatic interactions, H-bonding, functional groups complexation, and π-π electron donor-acceptor interactions. Besides that, BMF had the potential for repeated use. This research proposed a novel and promising method for LFX or other antibiotics adsorption removal.
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http://dx.doi.org/10.1016/j.biortech.2021.125698DOI Listing
November 2021

Global evolution of research on green energy and environmental technologies:A bibliometric study.

J Environ Manage 2021 Nov 28;297:113382. Epub 2021 Jul 28.

College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha, 410082, China.

To better grasp developments and trends in research on green energy and environmental technologies, the published literatures in the Web of Science Core Collection database from 1998 to 2020 were utilized to reveal critical information and guidance on what has been investigated, and what are the changes in research interests using a bibliometric method. Herein, yearly quantitative distribution of literatures, author contribution and collaboration, productive and influential institutions and countries/territories, co-citation analysis, keywords co-occurrence analysis, and research frontier identification are analyzed via information visualization technology. The results show that the publications on green energy and environmental technologies have grown exponentially, that China, the USA, and Italy are the most active countries, but the global cooperation is not close at present. The research frontier identification results reveal that the categories of energy, wastewater, and performance remain stable, while the trending up and emerging categories of catalyst and CO emission show clear shift over the last decade, indicating that catalytic production of clean energy and value-added chemicals, strategies to reduce greenhouse gas emissions, and other related studies to solve the global energy crisis and environmental problems are the research frontiers. This bibliometric study provides unique insights and offers research guidance on green energy and environmental technologies.
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http://dx.doi.org/10.1016/j.jenvman.2021.113382DOI Listing
November 2021

Current progress in electrochemical anodic-oxidation of pharmaceuticals: Mechanisms, influencing factors, and new technique.

J Hazard Mater 2021 09 6;418:126313. Epub 2021 Jun 6.

College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China. Electronic address:

Various pharmaceuticals have been detected in natural water and wastewater bodies, causing threats to water ecosystem and human health. Although electrochemical anodic-oxidation (EAO) has been shown to be efficient for pharmaceuticals degradation from aqueous solution, it still has a distinct need to apply EAO technology for pharmaceuticals removal rationally. This review provides the most recent progress on the mechanisms, influencing factors, and new technique of EAO for pharmaceuticals degradation. The mechanism and superiority of EAO were analyzed. Major influencing factors (e.g., electrode materials, electrochemical reactor, applied current density, anode-cathode distance, electrolyte type and concentration, initial solution pH value, and initial pharmaceuticals concentration) were discussed on the removal of pharmaceuticals. The latest development of reactive electrochemical membranes (REM) was regarded as an emerging EAO technique, and it was also highlighted. This work revealed that the EAO of pharmaceuticals has extraordinary application prospects in the field of water and wastewater treatment.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126313DOI Listing
September 2021

Clinical efficacy of vitamin B in the treatment of mouth ulcer: a systematic review and meta-analysis.

Ann Palliat Med 2021 Jun 16;10(6):6588-6596. Epub 2021 Jun 16.

Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China.

Background: Our study sought to determine the efficacy of vitamin B in treating mouth ulcers.

Methods: The databases PubMed, Web of Science, Embase, Chinese National Knowledge Infrastructure (CNKI), and Wanfang were comprehensively searched to identify relevant articles published between 2010 and 2021. Subsequently, the clinical efficacy of vitamin B in the treatment of mouth ulcers was comprehensively and quantitatively evaluated through meta-analysis.

Results: Totally, 16 studies were finally included in the meta-analysis, including 1,534 patients. Patients who did not receive treatment were taken as controls, while those who were treated with vitamin B alone or vitamin B combined with pantothenic acid were included in the treatment group. In comparison with the control group, the effective rate was higher [odds ratio (OR) =5.24, 95% confidence interval (CI): 3.72 to 7.37, P<0.001] while the recurrence rate was lower (OR =0.194, 95% CI: 0.128 to 0.295, P<0.001) in the treatment group. Additionally, both the ulcer healing time [standardized mean difference (SMD) =-2.15, 95% CI: -2.80 to -1.50, P<0.001] and treatment time (SMD =-2.31, 95% CI: -2.67 to -1.96, P<0.001) in the treatment group were shorter than those of the control group.

Discussion: Vitamin B enables a higher effective rate and lower recurrence rate, accelerates ulcer healing, and shortens the course of treatment. Collectively, vitamin B has a high clinical value in treating patients with mouth ulcers.
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http://dx.doi.org/10.21037/apm-21-1064DOI Listing
June 2021

A review on percarbonate-based advanced oxidation processes for remediation of organic compounds in water.

Environ Res 2021 09 31;200:111371. Epub 2021 May 31.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha, 410028, China. Electronic address:

Sodium percarbonate (SPC) is considered a potential alternative to liquid hydrogen peroxide (HO) in organic compounds contaminated water/soil remediation due to its regularly, transportable, economical, and eco-friendly features. The solid state of SPC makes it more suitable to remediate actual soil and water with a milder HO release rate. Apart from its good oxidative capacity, alkaline SPC can simultaneously remediate acidized solution and soil to the neutral condition. Conventionally, percarbonate-based advanced oxidation process (P-AOPs) system proceed through the catalysis under ultraviolet ray, transition metal ions (i.e., Fe, Fe, and V), and nanoscale zero-valent metals (iron, zinc, copper, and nickel). The hydroxyl radical (OH), superoxide radical (O), and carbonate radical anion (CO) generated from sodium percarbonate could attack the organic pollutant structure. In this review, we present the advances of P-AOPs in heterogeneous and homogeneous catalytic processes through a wide range of activation methods. This review aims to give an overview of the catalysis and application of P-AOPs for emerging contaminants degradation and act as a guideline of the field advances. Various activation methods of percarbonate are summarized, and the influence factors in the solution matrix such as pH, anions, and cations are thoroughly discussed. Moreover, this review helps to clarify the advantages and shortcomings of P-AOPs in current scientific progress and guide the future practical direction of P-AOPs in sustainable carbon catalysis and green chemistry.
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http://dx.doi.org/10.1016/j.envres.2021.111371DOI Listing
September 2021

A novel modified Fe-Mn binary oxide graphite felt (FMBO-GF) cathode in a neutral electro-Fenton system for ciprofloxacin degradation.

Environ Pollut 2021 Oct 15;286:117310. Epub 2021 May 15.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China. Electronic address:

A graphite felt (GF) cathode was firstly modified by Fe-Mn binary oxide (FMBO), active carbon (AC), carbon black (CB), and polytetrafluoroethylene (PTFE), which exhibits satisfactory ciprofloxacin (CIP) removal efficiency at neutral pH value in electro-Fenton (EF) system. Morphological data showed that modified cathodes have larger surface area and volume pore as well as more active sites. And electrochemical properties have proved stronger current response after modification. In compassion to the unmodified GF, the FMBO/AC/CB modified GF (FMBO-GF) has wider pH range and higher CIP removal efficiency due to its unique nanoparticles structure. The CIP removal efficiency achieved 95.40% in 30 min, and the removal efficiency of total organic carbon (TOC) achieved 93.77% in 2 h when conditions were optimal (25 mg/L initial CIP concentration, 2 mA/cm current density, FMBO/AC: CB: PTFE of 1:1:5, and 7 initial pH value) in this study. The results of great degradation and mineralization of CIP in this study indicate that the FMBO-GF cathode has huge potential on antibiotics removals in neutral environment.
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http://dx.doi.org/10.1016/j.envpol.2021.117310DOI Listing
October 2021

High-efficiency degradation of p-arsanilic acid and arsenic immobilization with iron encapsulated B/N-doped carbon nanotubes at natural solution pH.

Sci Total Environ 2021 Sep 17;785:147152. Epub 2021 Apr 17.

College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China. Electronic address:

p-arsanilic acid (p-ASA) is still widely applied as feed additive in many countries. Accompanied with chemical reactions in the environment, p-ASA will release more toxic inorganic arsenic. In order to safely and efficiently treat p-ASA flow washing into the environment, iron encapsulated B/N-doped carbon nanotubes ([email protected]) were fabricated and used as the catalyst for the degradation of p-ASA. The calcination temperature and the dose of the iron salt have significant effects on the structure and properties of the catalysts. We have produced a series of catalysts of the same type to facilitate the degradation of p-ASA. Under optimal conditions of material ([email protected]) syntheses, both 95% degradation of p-ASA and 86% total arsenic immobilization can be obtained with oxidant (Peroxymonosulfate, PMS) and catalyst ([email protected]) treatment after 60 min. The effects of oxidant types (peroxydisulfate (PDS), PMS, hydrogen peroxide (HO)), amount, initial solution pH, inorganic anion, and other reaction conditions were studied in the p-ASA removal. In this Fenton-like reaction, the [email protected] exhibits high efficiency and excellent stability without complex preparation methods; besides, the advantages of short reaction time and natural reaction conditions in [email protected]/PMS system will promote the practical application of Fenton-like.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147152DOI Listing
September 2021

FeFe layered double hydroxide modified carbon felt cathode for removal of ciprofloxacin in electro-Fenton process.

Environ Res 2021 06 16;197:111144. Epub 2021 Apr 16.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China. Electronic address:

The disadvantages of limited working pH range and poor stability have hindered the practical application of traditional electro-Fenton process. In this research, a novel heterogeneous electro-Fenton (HEF) process with FeFe layered double hydroxide/carbon felt (FeFe LDH/CF) as cathode was developed for the rapid destruction of ciprofloxacin (CIP) in bulk solution. Effects of crucial influencing factors (initial pH, current intensity) on CIP degradation were investigated. Results indicated that FeFe LDH/CF cathode was efficient for CIP degradation (88.11%). Furthermore, CIP degradation performance in HEF could remain stable over wide range of pH (pH 3-9). The catalytic degradation of CIP in HEF process might be a combined effect of homogeneous EF reaction, anodic oxidation, and surface catalysis process via≡Fe/≡Fe cycle. Possible degradation pathways were proposed. The results suggested that FeFe LDH/CF cathode showed great application potential for CIP degradation.
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http://dx.doi.org/10.1016/j.envres.2021.111144DOI Listing
June 2021

Current progress in degradation and removal methods of polybrominated diphenyl ethers from water and soil: A review.

J Hazard Mater 2021 02 18;403:123674. Epub 2020 Aug 18.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China. Electronic address:

The widespread of polybrominated diphenyl ethers (PBDEs) in the environment has caused rising concerns, and it is an urgent endeavor to find a proper way for PBDEs remediation. Various techniques such as adsorption, hydrothermal and thermal treatment, photolysis, photocatalytic degradation, reductive debromination, advanced oxidation processes (AOPs) and biological degradation have been developed for PBDEs decontamination. A comprehensive review of different PBDEs remediation techniques is urgently needed. This work focused on the environmental source and occurrence of PBDEs, their removal and degradation methods from water and soil, and prospects for PBDEs remediation techniques. According to the up-to-date literature obtained from Web of Science, it could be concluded that (i) photocatalysis and photocatalytic degradation is the most widely reported method for PBDEs remediation, (ii) BDE-47 and BDE-209 are the most investigated PBDE congeners, (iii) considering the recalcitrance nature of PBDEs and more toxic intermediates could be generated because of incomplete degradation, the combination of different techniques is the most potential solution for PBDEs removal, (iv) further researches about the development of novel and effective PBDEs remediation techniques are still needed. This review provides the latest knowledge on PBDEs remediation techniques, as well as future research needs according to the up-to-date literature.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123674DOI Listing
February 2021

Electrochemical treatments of coking wastewater and coal gasification wastewater with Ti/TiO and Ti/RuO-IrO anodes.

J Environ Manage 2020 Jul 13;265:110571. Epub 2020 Apr 13.

College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, PR China. Electronic address:

Electrochemical treatments of coking wastewater (CW) and coal gasification wastewater (CGW) were conducted with Ti/TiO and Ti/RuO-IrO anodes. The performances of Ti/TiO and Ti/RuO-IrO anodes were investigated by analyzing the effects of five key influencing factors including anodes material, current density, anode-cathode distance, initial pH value, and electrolyte type. The removal efficiencies of total organic carbon (TOC) were analyzed during the processes of CW and CGW electro-oxidation. The removal efficiencies of sixteen polynuclear aromatic hydrocarbons (PAHs) in CW and CGW by electro-oxidation were also explored to further assess the electrochemical activities of Ti/TiO and Ti/RuO-IrO anodes. The Ti/TiO anode achieved 78.7% COD removal efficiency of CW, 85.8% COD removal efficiency of CGW, 50.3% TOC removal efficiency of CW, and 54.8% TOC removal efficiency of CGW, higher than the Ti/RuO-IrO anode (76.7%, 78.1%, 44.8% and 46.8%). The COD removal efficiencies increased with the applied current density, decreased with the increase of the anode-cathode distance, and slightly decreased with the increase of the initial pH value. Meanwhile, the removal efficiencies of sixteen PAHs by the Ti/TiO anode were mostly higher than those by the Ti/RuO-IrO anode. By comprehensively analyzing the performances of Ti/TiO and Ti/RuO-IrO anodes on electrochemical treatments of CW and CGW, this study may supply insights into the application potentials of these anodes to the electrochemical treatments of real wastewater.
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http://dx.doi.org/10.1016/j.jenvman.2020.110571DOI Listing
July 2020

Effect of Fe, Mn catalysts on the performance of electro-Fenton degradation of antibiotic ciprofloxacin, and expanding the utilizing of acid mine drainage.

Sci Total Environ 2020 Jun 24;720:137560. Epub 2020 Feb 24.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China. Electronic address:

In this work, the removal of ciprofloxacin (CIP) was studied by electro-Fenton (EF) technique using different molar ratio of Mn/Fe based on a chemically modified graphite felt (MGF) cathode. The CIP removal efficiency reached 95.62% in 30 min and the removal efficiency of total organic carbon (TOC) reached 94.00% in 8 h under optimal conditions (50 mg/L initial CIP concentration, 400 mA applied current, 2:1 M ratio of Mn/Fe, and 3 initial pH value). A possible pathway of CIP degradation was supposed according to the analysis of the by-products detected during the EF process. An expanding experiment for CIP removal was also conducted by using acid mine drainage (AMD) rich in iron and manganese to replace the homogeneous solution in EF, and the CIP removal efficiency of 89.00% in 60 min under the optimal conditions may assign new perspectives for organic pollutants removals by utilizing AMD.
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http://dx.doi.org/10.1016/j.scitotenv.2020.137560DOI Listing
June 2020

Remediation of persistent organic pollutants in aqueous systems by electrochemical activation of persulfates: A review.

J Environ Manage 2020 Apr 17;260:110125. Epub 2020 Jan 17.

College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, PR China.

Sulfate-radical-based advanced oxidation processes (SR-AOPs) have been widely applied in environmental remediation during the past decade, especially in the degradation of refractory organic contaminants. The electrochemical method, which is considered as one of the most efficient ways to generate sulfate radical, has been extensively investigated for the activation of persulfate recently. This work presented a thorough assessment towards the performance of electrochemically activated persulfate for the removal of persistent organic pollutants (POPs) in aqueous systems. The mechanism and superiority of electrochemically activated persulfates were revealed accordingly. Some major factors (e.g., electrode material, pH, current density, and persulfate concentration) influencing the electrochemical activation of persulfates to remove POPs were also discussed. Considering the increasing quantity of publications on this subject, it is significant to broader guidelines such as the efficiency for practical application, quantization of organic by-products, and cost-effectiveness of the electrochemical method to optimize active persulfate in the water treatment processes.
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http://dx.doi.org/10.1016/j.jenvman.2020.110125DOI Listing
April 2020

Effect of RM-based-passivator for the remediation of two kinds of Cd polluted paddy soils and mechanism of Cd(II) adsorption.

Environ Technol 2021 Apr 23;42(10):1623-1633. Epub 2019 Oct 23.

College of Resources and Environment, Hunan Agriculture University, Changsha, People's Republic of China.

This study aimed to investigate the effects of red mud-based-passivator (RM-based-passivator) on rice yield, cadmium (Cd) in brown rice, pH and available Cd in Cd-polluted soil by pot experiments, and to explore the adsorption mechanism of the passivator by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis. The results showed that this passivator obviously improved the pH, reduced the available Cd in soil and the Cd content in brown rice in Changsha Cd polluted soil (CS soil), while had little effect on Hengyang Cd polluted soil (HY soil). Compared with the control, the soil pH increased in the range from 0.31 to 1.37, the available Cd in soil decreased in the range from 13.25% to 52.34%, and the total Cd in brown rice decreased in the range from 46.44% to 84.98% in CS soil. Considering the impacts of RM-based-passivator on the growth of rice, the Cd content in brown rice, and the pH and available Cd in soil, 0.10-0.30% (w/w) of the passivator is recommended to apply in CS soil but not in HY soil. Based on the analysis of SEM, EDX, FTIR and XRD, the mechanism of Cd(II) adsorption by RM-based-passivator included physical adsorption, surface complexation and ion exchange. The present results indicated that the appropriate addition of RM-based-passivator could be an effective strategy for the remediation of acidic Cd-polluted soils.
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http://dx.doi.org/10.1080/09593330.2019.1675772DOI Listing
April 2021

Current progress in the adsorption, transport and biodegradation of antibiotics in soil.

J Environ Manage 2019 Dec 25;251:109598. Epub 2019 Sep 25.

International Joint Laboratory of Hunan Agricultural Typical Pollution Restoration and Water Resources Safety Utilization, College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China. Electronic address:

Antibiotic residues in soil may cause potential risks to human health and soil ecosystems. To avoid these potential risks, comprehensive study of the adsorption, transport and biodegradation of antibiotics in soil is very imperative. This review provided current views about the most recent studies, which have been conducted toward the adsorption, transport and biodegradation of antibiotics in soil. The influencing factors affecting the adsorption behaviors of antibiotics in soil, including the antibiotics properties (e.g., molecular structure, hydrophobicity, polarity, polarizability, and spatial configuration) and the soil characteristics (e.g., soil type, soil pH, coexisting ions, and soil organic matter), were discussed. The effects of fertilizer colloids, porous media, and pH of soil on the transport behaviors of antibiotics were analyzed. The biodegradation of antibiotics in soil were also highlighted by investigating the effects of soil microbiome, soil pH, soil temperature, and interactions between antibiotics. Prospects of antibiotics adsorption, transport and biodegradation were also proposed.
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http://dx.doi.org/10.1016/j.jenvman.2019.109598DOI Listing
December 2019

Research progress on the removal of hazardous perfluorochemicals: A review.

J Environ Manage 2019 Nov 6;250:109488. Epub 2019 Sep 6.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China. Electronic address:

Perfluorinated substances are global and ubiquitous pollutants. The persistent organic pollution of perfluorochemicals (PFCs) have drawn attentions worldwide. In view of the current need for sustainable development, many researchers began to study the remediation techniques for PFCs. Due to its unique hydrophobic and oil-phobic characteristics, the requirements for the PFCs removal process are different, so that their remediation techniques are still under continuous exploration. Hence, this review summarized the removal behaviors of various PFCs on different materials which supply a good foundation for future investigations in this field. It is evident from previous literature that every remediation techniques for PFCs has its own advantages. Among various currently evaluated removal methods, adsorption seems to be one of the most commonly used and recognized techniques for PFCs pollution control. Other innovative and promising techniques, such as physical and/or chemical methods, have also been tested for their effectiveness in removing perfluorinated compounds.
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http://dx.doi.org/10.1016/j.jenvman.2019.109488DOI Listing
November 2019

A sustainable ferromanganese biochar adsorbent for effective levofloxacin removal from aqueous medium.

Chemosphere 2019 Dec 29;237:124464. Epub 2019 Jul 29.

Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.

This present study reported the synthesis and characterization of a low-cost, environment friendly and high efficient biochar, ferromanganese modified biochar (Fe/Mn-BC) for the removal of levofloxacin (LEV) from aqueous medium. Fe/Mn-BC was synthesized through the facile co-precipitation of Fe, Mn with vinasse wastes and then pyrolysis under controlled conditions. The characterization of Fe/MnBC was analyzed by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction patterns (XPS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman. Some influencing factors (e.g., pH, Fe/Mn-BC dosage, initial LEV concentration, ionic strength, contact time and temperature) were comprehensively investigated. The results manifested that the adsorption process of LEV onto Fe/Mn-BC was high pH dependence and the maximum adsorption capacity was achieved at pH 5. Moreover, the adsorption capacity of LEV was increased with increasing ionic strength. To gain a clearer perspective on the adsorption behavior of LEV onto Fe/Mn-BC, the adsorption kinetics and isotherms were also performed, revealing pseudo-second-order and Freundlich model had a better fitting effect. Reusability experiments indicated that Fe/Mn-BC could maintain a certain adsorption capacity for LEV after 5 recycles. Overall, this work showed that Fe/Mn-BC was an effective and promising adsorbent for eliminating LEV from aqueous medium.
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http://dx.doi.org/10.1016/j.chemosphere.2019.124464DOI Listing
December 2019

Evaluating tetracycline degradation pathway and intermediate toxicity during the electrochemical oxidation over a Ti/TiO anode.

Water Res 2018 06 12;137:324-334. Epub 2018 Mar 12.

School of Environment, Tsinghua University, Beijing 100084, PR China. Electronic address:

Tetracycline (TC) is one of the most widely used antibiotics with significant impacts on human health and thus it needs appropriate approaches for its removal. In the present study, we evaluated the performance and complete pathway of the TC electrochemical oxidation on a Ti/TiO anode prepared by plasma spraying. Morphological data and composition analysis indicated a compact coating layer on the anode, which had the characteristic peaks of TiO as active constituent. The TC electrochemical oxidation on the Ti/TiO anode followed a pseudo-first-order kinetics, and the TC removal efficiency reached 95.8% in 40 min. The influential factors on TC decay kinetics included current density, anode-cathode distance and initial TC concentration. This anode also had high durability and the TC removal efficiency was maintained over 95% after five times reuse. For the first time, we unraveled the complete pathway of the TC electrochemical oxidation using high-performance liquid chromatograph (HPLC) and gas chromatograph (GC) coupled with mass spectrometer (MS). ·OH radicals produced from electrochemical oxidation attack the double bond, phenolic group and amine group of TC, forming a primary intermediate (m/z = 461), secondary intermediates (m/z = 432, 477 and 509) and tertiary intermediates (m/z = 480, 448 and 525). The latter were further oxidized to the key downstream intermediate (m/z = 496), followed by further downstream intermediates (m/z = 451, 412, 396, 367, 351, 298 and 253) and eventually short-chain carboxylic acids. We also evaluated the toxicity change during the electrochemical oxidation process with bioluminescent bacteria. The bioluminescence inhibition ratio peaked at 10 min (55.41%), likely owing to the high toxicity of intermediates with m/z = 461, 432 and 477 as obtained from quantitative structure activity relationship (QSAR) analysis. The bioluminescence inhibition ratio eventually decreased to 16.78% in 40 min due to further transformation of TC and intermediates. By comprehensively analyzing the influential factors and complete degradation pathway of TC electrochemical oxidation on the Ti/TiO anode, our research provides deeper insights into the risk assessment of intermediates and their toxicity, assigning new perspectives for practical electrochemical oxidation to effectively eliminate the amount and toxicity of TC and other antibiotics in wastewater.
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http://dx.doi.org/10.1016/j.watres.2018.03.030DOI Listing
June 2018

The Development of a Dual-Warhead Impact System for Dynamic Linearity Measurement of a High-g Micro-Electro-Mechanical-Systems (MEMS) Accelerometer.

Sensors (Basel) 2016 Jun 8;16(6). Epub 2016 Jun 8.

Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030000, Shanxi, China.

Despite its extreme significance, dynamic linearity measurement for high-g accelerometers has not been discussed experimentally in previous research. In this study, we developed a novel method using a dual-warhead Hopkinson bar to measure the dynamic linearity of a high-g acceleration sensor with a laser interference impact experiment. First, we theoretically determined that dynamic linearity is a performance indicator that can be used to assess the quality merits of high-g accelerometers and is the basis of the frequency response. We also found that the dynamic linearity of the dual-warhead Hopkinson bar without an accelerometer is 2.5% experimentally. Further, we verify that dynamic linearity of the accelerometer is 3.88% after calibrating the Hopkinson bar with the accelerometer. The results confirm the reliability and feasibility of measuring dynamic linearity for high-g accelerometers using this method.
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http://dx.doi.org/10.3390/s16060840DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4934266PMC
June 2016

A three-dimensional Zn(II) coordination framework: poly[[μ2-(E)-1,2-bis(pyridin-4-yl)ethene][μ4-(E)-2,2'-(diazene-1,2-diyl)dibenzoato][μ2-(E)-2,2'-(diazene-1,2-diyl)dibenzoato]dizinc(II)].

Acta Crystallogr C Struct Chem 2014 Mar 13;70(Pt 3):277-80. Epub 2014 Feb 13.

College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, Henan, People's Republic of China.

In the title coordination polymer, [Zn2(C14H8N2O4)2(C12H10N2)]n, the asymmetric unit contains one Zn(II) cation, two halves of 2,2'-(diazene-1,2-diyl)dibenzoate anions (denoted L(2-)) and half of a 1,2-bis(pyridin-4-yl)ethene ligand (denoted bpe). The three ligands lie across crystallographic inversion centres. Each Zn(II) centre is four-coordinated by three O atoms of bridging carboxylate groups from three L(2-) ligands and by one N atom from a bpe ligand, forming a tetrahedral coordination geometry. Two Zn(II) atoms are bridged by two carboxylate groups of L(2-) ligands, generating a [Zn2(CO2)2] ring. Each loop serves as a fourfold node, which links its four equivalent nodes via the sharing of four L(2-) ligands to form a two-dimensional [Zn2L4]n net. These nets are separated by bpe ligands acting as spacers, producing a three-dimensional framework with a 4(6)6(4) topology. Powder X-ray diffraction and solid-state photoluminescence were also measured.
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http://dx.doi.org/10.1107/S2053229614001077DOI Listing
March 2014

High-yield synthesis of single crystalline tin-doped indium oxide octahedrons via a low-temperature, catalyst-free process.

Nanotechnology 2006 Jul 20;17(14):3523-6. Epub 2006 Jun 20.

We report a large-scale synthesis of micron and nanosized tin-doped indium oxide (ITO) octahedrons via an ultrasonic spray assisted chemical vapour deposition, in which no catalyst is involved. The single crystalline nature of the ITO octahedrons was revealed by high-resolution transmission electron microscopy. The formation of ITO octahedrons, which are bounded by eight {111} facets, is due to the lowest surface energy of the {111} facet. The size of the octahedron was found to be strongly dependent on deposition temperature and the concentration of the precursor solution, with perfectly shaped ITO octahedrons being synthesized at a temperature between 400 and 550 degrees C. By simply changing the concentration of the precursor solution, we can produce well-dispersed ITO octahedral particles, dense ITO films with octahedral grains, or clusters of octahedral.
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http://dx.doi.org/10.1088/0957-4484/17/14/027DOI Listing
July 2006
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