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.
关键词：
Antioxidant enzymes;Cadmium;Chemical forms;Gene expression;Salix;Subcellular distribution
摘要：
Cadmium (Cd) is a highly toxic element for plant. In order to reveal the effects of NaHS on Cd uptake, physiological and molecular responses of salix to Cd toxicity, NaHS-mediated hydroponics of salix under Cd stress was performed. The addition of NaHS reduces the salix biomass reduction caused by Cd poisoning. NaHS did not obviously reduce the total Cd level absorbed by salix, but significantly reduced the soluble Cd fractions and increased the insoluble Cd fractions in salix leaves and roots. NaHS reduced the distribution of Cd in organelles and vacuoles and increased the distribution of Cd in the cell wall of salix leaves and roots. NaHS promotes the level of antioxidant enzyme activities and gene expression of salix, and reduces the accumulation of MDA and H2O2 caused by Cd. NaHS increases the content of GSH and endogenous H2S in salix leaves and roots. The addition of NaHS can reduce the toxicity of Cd to salix without obviously reducing the Cd uptake by salix, thus improving the application of salix in phytoremediation to Cd.
作者机构：
[杨雨中; 朱健; 肖媛媛; 谭蓉; 王平; 陈润华; 徐海音; 杨雄] College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha;410004, China;Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha;[杨雨中; 朱健; 肖媛媛; 谭蓉; 王平; 陈润华; 徐海音; 杨雄] 410004, China;[朱健; 王平] 410004, China<&wdkj&>Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha
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
摘要：
In this study, a novel method based on the magnetic Fe/C crosslinked nanoparticles (MNZVI/CNTs-OH) is reported for the effective removal of Cr(VI) in aqueous solutions. Parameters that influence the effectiveness of the nanoparticles, such as pH, temperature, reaction time, and particle dosage, was analyzed. It was found that MNZVI/CNTs-OH particles exhibit significantly higher activity toward Cr(VI) removal than bare NZVI, carbon nanotubes (CNTs), and other synthetic nanomaterials. Under optimized conditions, the removal efficiency of Cr(VI) by MNZVI/CNTs-OH is up to 98% with an initial contaminant concentration of 50 mg/L, and chromium content in the residue up to 48 mg/g. Physical characterizations, including Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and TG-TD measurements, provide insights into the working mechanism of Cr(VI) purification. Our findings suggest that immobilization of MNZVI onto carbon nanotubes increase the covalent bond property, while crosslinked nanoparticles (NPs) provide the electron transfer passage from the NZVI surface and improves the dispersity of the MNZVI, thus enhancing the performance. These results demonstrate the potential of the MNZVI/CNTs-OH nanoparticles for the rapid and efficient treatment of Cr(VI)-containing wastewater.
摘要：
Koelreuteria paniculata were cultivated in nutrient solution with different concentrations of Cd (0, 50, 150, 250 and 500microM) and sampled after 90 days. The resistance, translocation, accumulation and stress responses in Koelreuteria paniculata were investigated by hydroponic experiments. The results showed that Koelreuteria paniculata is an efficient Cd excluder that can tolerate high concentrations of Cd (up to 150-250microM of Cd). The concentration of Cd never exceeds 5ppm in leaves and 10ppm in roots. The high concentration of Cd (>/= 250microM) had a toxic effect on K. paniculata and significantly restricted the plant growth. The accumulation ability of Cd by different plant tissues followed the sequence of roots > leaves > stems. The bioconcentration factors and translocation factors both were less than 1. Cd has the highest content in the cell wall and is migrated to soluble fractions and organelles at high concentrations. Undissolved Cd phosphate, pectates and protein-bound Cd were the predominant forms. The low concentration of Cd (</=150microM) promoted the synthesis of soluble proteins, AsA and GSH, while high concentration of Cd clearly inhibited the physiological and biochemical process, caused membrane lipid peroxidation and severe membrane damages, and increased MDA and H2O2 contents. POD, CAT and SOD exhibited positive and effective responses to low concentration Cd stress, but could not remove the toxicity caused by high concentration Cd stress. The content of IAA, GA and ZT decreased and ABA content was significantly increased under high-concentration Cd stress.
