摘要：
Single-atom catalysts have wide application prospects in peroxydisulfate (PDS)-based advanced oxidation process to degrade organic pollutants, but its catalytic performance is limited due to its cost, Metal-N coordination number, and single-atom loading amount. Herein, a novel nitrogen doped algal-based carbon confined singleatom copper catalyst (Cu-N/C-SAC((S))) was synthesized using molten salt assisted pyrolysis and coupling with PDS to degrade tetracycline (TC). AC-HAADF-STEM and XAFS analysis proved that single atom Cu was loaded (Content 1.9 %) successfully and coordinated with two N and two C. XPS and XANES spectra analysis suggested that Cu atoms mainly existed in a positive divalent state in Cu-N/C-SAC(S). When the catalyst dosage of Cu-N/CSAC((S)) was 0.1 g/L, TC was almost completely removed. Moreover, Cu-N/C-SAC(S) had a broad pH adaptation range and strong ability against interference. Singlet oxygen (O-1(2)), superoxide radicals (center dot O-2(-)), and electron transfer had an important contribution for TC removal. DFT calculations confirmed that the activation process of Cu-N/C-SAC((S)) producing SO4 center dot- was easier than the nitrogen doped blue-green algal-based carbon (N-BGAC). In addition, Cu-N/C-SAC((S)) possessed good recyclability and stability. The main degradation pathways of TC were analyzed, and the toxicity of the intermediates was calculated. This study provides a new solution strategy for the resource utilization of waste biomass, and provides technical support and theoretical guidance for the efficient application of single-atom catalysts in organic wastewater.
作者机构：
[Wang, Ping; Jia, Meiying; Xu, Haiyin] Cent South Univ Forestry & Technol, Coll Life & Environm Sci, Coll Environm Sci & Engn, Yuelushan Lab, Changsha 410004, Peoples R China.;[Ma, Yuanyuan] Tongji Univ, Sch Environm Sci & Engn, State Key Lab Pollut Control & Resource Reuse, Shanghai 200092, Peoples R China.;[Yang, Zhaohui; Kang, Anqi; Wang, Wenxuan; Xiong, Weiping] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Peoples R China.
通讯机构：
[Wang, P ] C;Cent South Univ Forestry & Technol, Coll Life & Environm Sci, Coll Environm Sci & Engn, Yuelushan Lab, Changsha 410004, Peoples R China.
摘要：
The development of photoanodes with stable photoelectrocatalytic (PEC) performance is crucial to solve the secondary pollution caused by powder-based catalysts in antibiotic removal. In this study, FTO-alpha-Fe2O3@CeO2 photoanodes were prepared using a short-time effective electrochemical pulse deposition method for PEC degradation of antibiotics. Based on the outstanding light absorption capability conferred by the narrow bandgap of alpha-Fe2O3, the separation advantage of photogenerated carriers conferred by the unique oxygen vacancies of CeO2 and the variable polymetallic ion valence states (Fe2+/Fe3+, Ce3+/Ce4+), the target photoanode could achieve 93.13% degradation efficiency for tetracycline (TC) within 120 min. Ion leaching after degradation was controlled at an environmentally friendly level, and the universality was evaluated in configuration solutions from actual water. The matched Z-type heterojunction energy band structure and synergistic interaction between alpha-Fe2O3 and CeO2 enhanced the catalytic efficiency of the photoanode, and the main contribution was attributed to the generation of the free radical <middle dot>OH and active species h+. Furthermore, cyclic voltammetric characteristic curves and Tafel curves demonstrated the advantages of the FTO-alpha-Fe2O3@CeO2 photoanode in terms of stability and reaction kinetics. Ultimately, more complete TC degradation pathways were proposed based on the 13 intermediates detected, and the toxicity of the intermediates was assessed. This work enriched the development of catalytic photoanodes and provides new ideas for antibiotic removal involving non-powder catalysts.
作者机构：
[Liu, Yuwei; Lin, Baining; Luo, Lukai; Liu, Hongyang; Zhou, Yonghua] Cent South Univ, Coll Chem & Chem Engn, Changsha 410083, Peoples R China.;[Wang, Hanqing; Wang, Ping; Mao, Yu] Cent South Univ Forestry & Technol, Coll Environm Sci & Engn, Hunan Engn Res Ctr Full Life Cycle Energy Efficien, Changsha 410004, Peoples R China.
关键词：
boron defects;direct dehydrogenation of ethylbenzene;metal-free catalysis;phosphorus doped boron nitride;styrene
摘要：
Ethylbenzene dehydrogenation: The m‐PBN with the optimal concentration of B defects improved the styrene production rate to 22.54 mmolST g−1 h−1. Meanwhile, when it was further in‐situ grown on Al2O3, the styrene production rate increased to 23.22 mmolST g−1 h−1 and stably run for more than 300 h. Abstract Phosphorus‐doped boron nitride (PBN) has been confirmed as an effective metal‐free catalyst for the direct dehydrogenation (DDH) of ethylbenzene to styrene. In this paper, we further used barbituric acid as co‐reactant sources to create B defects in both PBN and mesoporous PBN (m‐PBN) materials. The XPS, N2 adsorption‐desorption, UV‐vis DRS, EPR, 11B SS NMR characterizations indicated both the electronic and pore structures of the catalyst with B defects were adjusted. Except for the improvement of mass transfer caused by B defects, DFT calculations showed the increase of electron density in B defects areas could enhance the breaking of C−H in ethylbenzene and the bond‐forming of H−H, which was acted to improve the catalytic activity. The m‐PBN with B defects delivered the styrene production rate of 22.54 mmolST g−1 h−1 and stably run 300 h when in‐situ grown on Al2O3, proving that defect tuning strategy is useful to construct efficient catalysts for styrene production.
作者机构：
[何其浩; 王平] College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China;[周韬; 孙吉康; 白磊] College of Life Science and Technology, Central South University of Forestry and Technology, Changsha, 410004, China;[刘志明] Department of Biology, Eastern New Mexico University, Portales, NM 88130, United States
作者机构：
[Huang, Chenxi; Cao, Jingxiao; Li, Meifang; Wang, Ping] Cent South Univ Forestry & Technol, Coll Environm Sci & Engn, Shaoshan South Rd, Changsha 410004, Peoples R China.;[Huang, Chenxi; Cao, Jingxiao; Li, Meifang; Wang, Ping] Cent South Univ Forestry & Technol, Fac Life Sci & Technol, Changsha 410004, Peoples R China.;[Liu, Yunguo; Tan, Xiaofei] Hunan Univ, Coll Environm Sci & Engn, Lushan South Rd, Changsha 410082, Hunan, Peoples R China.;[Liu, Yunguo; Tan, Xiaofei] Hunan Univ, Key Lab Environm Biol & Pollut Control, Minist Educ, Lushan South Rd, Changsha 410082, Hunan, Peoples R China.;[Liu, Shaobo] Cent South Univ, Sch Architecture & Art, Lushan South Rd, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Wang, Ping] C;College of Environmental Science and Engineering, Central South University of Forestry and Technology, Tianxin District, Changsha, People’s Republic of China<&wdkj&>Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, People’s Republic of China
摘要：
<jats:title>Abstract</jats:title><jats:p>Humic acids (HAs) widely exist in water environment, and has an important impact on the adsorption of pollutants. Herein, HAs (both dissolved and coated) was employed to assess the effect on the removal of the organic contaminant tetracycline (TC) by K<jats:sub>2</jats:sub>CO<jats:sub>3</jats:sub> modified magnetic biochar (KMBC). Results showed that low concentration of dissolved HAs promoted TC removal, likely due to a bridging effect, while higher concentration of dissolved HAs inhibited TC adsorption because of the competition of adsorption sites on KMBC. By characterization analysis, coated HAs changed the surface and pore characteristics of KMBC, which suppressed the TC removal. In a sequential adsorption experiment involving dissolved HAs and TC, the addition of HAs at the end of the experiment led to the formation of HAs-TC ligands with free TC, which improved the adsorption capacity of TC. TC adsorption by KMBC in the presence of dissolved HAs and coated HAs showed a downward trend with increasing pH from 5.0 to 10.0. The TC adsorption process was favorable and endothermic, and could be better simulated by pseudo-second-order kinetics and Freundlich isotherm model. Hydrogen bonds and <jats:italic>π</jats:italic>–<jats:italic>π</jats:italic> interactions were hypothesized to be the underlying influencing mechanisms.</jats:p>
关键词：
Elaeagnusangustifolia L. Gum;Porous Carbon;Electrochemical Analysis;Chloramphenicol
摘要：
<jats:p>In this study, the method for detection of chloramphenicol was investigated by electrochemical sensor; the sensor was constructed by biomass derived porous carbon. At first, porous carbon doped with hetroatoms (nitrogen, sulfur, phosphorus) was synthesized based on the use of pyrolysis
and high temperature carbonization methods.<jats:italic> Elaeagnusangustifolia L.</jats:italic> gum was used as the carbon source in the facile template-free process. The biomass derived porous carbon was then used as the active electrode material for antibiotic sensing. The chemically modified electrodes properties
were studied with the cyclic voltammetry and differential pulse voltammetry methods. The effects of the scan rate, accumulation time and pH, were carefully considered. Comparison with other working electrodes at the optimized conditions indicated that the N, S, P triple doped porous carbon
modified glassy carbon electrode appeared a well-defined reduction peak towards chloramphenicol. The linear concentration response of chloramphenicol ranged from 1 to 40 <jats:italic>μ</jats:italic>M (<jats:italic>R</jats:italic>=0.9903) and 50 to 500 <jats:italic>μ</jats:italic>M (<jats:italic>R</jats:italic>=0.9923), and a low detection limit of 0.01 <jats:italic>μ</jats:italic>M
(S/N=3). Furthermore, the constructed novel electrochemical sensor was used for detection of chloramphenicol in real samples and achieved satisfactory recovers.</jats:p>
作者机构：
[尹静玄; 王平; 徐海音; 张睿琦; 赵珮伶; 聂香兰; 彭创新; 龚绘林; 梁云涛] College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构：
College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, China
摘要：
<jats:title>Abstract</jats:title><jats:p>In this study, a molybdenum disulfide/multiwalled carbon nanotubes (MoS<jats:sub>2</jats:sub>@MWCNTs) nanocomposite was synthesized by employing a simple hydrothermal method. The flower‐like structure of the MoS<jats:sub>2</jats:sub>@MWCNTs was characterized via scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the load of crystalline MoS<jats:sub>2</jats:sub> was verified via X‐ray diffraction (XRD) and energy‐dispersive spectroscopy (EDS). The as‐prepared MoS<jats:sub>2</jats:sub>@MWCNTs nanocomposite was used to modify glassy carbon electrode (GCE) as an electrochemical sensor for detecting aristolochic acids (AAs). With the optimized parameters, the proposed electrochemical sensor exhibited good sensitivity and a broad linear concentration range for detecting AAs from 0.2 to 10 <jats:styled-content>μ</jats:styled-content>mol/L and 10 to 100 <jats:styled-content>μ</jats:styled-content>mol/L, with the sensitivity of −3.10 <jats:styled-content>μ</jats:styled-content>A/(<jats:styled-content>μ</jats:styled-content>mol/L) and −0.91 <jats:styled-content>μ</jats:styled-content>A/(<jats:styled-content>μ</jats:styled-content>mol/L), respectively. The detection limit was also calculated as 0.06 <jats:styled-content>μ</jats:styled-content>mol/L (S/N=3) based on the low background signal. Furthermore, the modified electrochemical sensor exhibited good selectivity, repeatability, reproducibility, and stability, thus showing potential application for detecting AA in chinese herbs with good mean recovery and accuracy. In other words, the MoS<jats:sub>2</jats:sub>@MWCNTs/GCE can be used as an excellent platform to detect AAs.</jats:p>
摘要：
Zanthoxylum is a precious medicinal woody plant with a very low seed germination rate in China. The gibberellin (GA) treatment extremely increased the germination rate of zanthoxylum seeds. Our previous transcriptome data showed that exogenous GA played a negative role in the expression levels of genes involved in lipid metabolism during imbibition. Our present data indicated that compared with the GA-treated seeds, the soluble sugars were more quickly consumed and lipid breakdown was prematurely and actively initiated in the water-treated seeds during the early germination. However, the application of sucrose could improve the germination of water-treated seeds and significantly inhibit lipid breakdown. Both the application of sucrose and exogenous GA could significantly reduce the catalytic activities of sugar-dependent 1 (SDP1) and isocitratelyase (ICL), the expressions of SDP1 and ICL genes, and decrease the products of lipid breakdown as well during the early germination. We suggested that exogenous GA might enhance starch hydrolysis by promoting the catalytic activity of a-amylase to supplement metabolically consumed soluble sugars, thus the increased sugars levels would help to inhibit the lipid breakdown to mitigate oxidative damages in the early germination of zanthoxylum seeds. In the end, we summarized the possible molecular mechanism on the exogenous GA weakening lipid breakdown by increasing soluble sugars levels in the early germination of zanthoxylum seeds.
摘要：
The frequent occurrence of thallium (Tl) in surface water has led to the imposition of strict environmental regulations. The need for an overview of effective and feasible technology to remove Tl from water/wastewater has therefore become urgently. This review introduced the current available methods for Tl removal, including adsorption, oxidation-reduction precipitation, solvent extraction and ion exchange processes, and summarized their advantages and disadvantages. The results showed that a single treatment technology was difficult to remove Tl to a trace level of "mug L(-1)", which required combined multi-technology to enhance the removal efficiency. In addition, the potential emergency and feasible technologies for Tl removal were recommended. However, several fundamental issues, such as the comparative toxicity of Tl(I) and Tl(III), the confliction of hydrolysis constants, the interference of complexant ligands as well as the influence of redox potential, were still needed to be addressed, since they would profoundly affect the selection of adopted treatment methods and the behavior of Tl removal. Future research efforts concerning the improvement of existing Tl removal technologies should be devoted to (a) developing multi-functional chemicals and adsorbents, non-toxic extractants, easy-recovery ion exchange resin and high-efficient coupling technology for advanced treatment, (b) carrying out large-scale experiments and economic assessment for real wastewater, and (c) providing safe-disposal treatment for the exhausted adsorption materials or sludge.
作者机构：
[李文娟] School of Life Science and Technology, Central South University of Forestry and Technology, Changsha, 410004, China;[徐海音; 尹静玄; 王平; 朱姗姗] College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构：
[Wang, P.] C;College of Environmental Science and Engineering, China
