Ultrasound-assisted electrodeposition synthesis of nZVI-Pd/AC toward reductive degradation of methylene blue

Environmental Science and Pollution Research - A novel composite (nZVI/Pd-AC) was prepared by loading nanoscale zero-valent iron (nZVI) and Pd on activated carbon (AC) electrode under...     

An asymmetric analysis of the impacts of energy use on carbon dioxide emissions in the G7 countries

Environmental Science and Pollution Research - The foremost theme of the paper is to explore the asymmetric/symmetric impact of energy consumption on the carbon dioxide emission of G7 countries...     

Effects of intercropping with floricultural accumulator plants on cadmium accumulation in grapevine

Environmental Science and Pollution Research - Grapevine (Vitis vinifera L.) intercropping with floricultural cadmium (Cd) accumulator plants (Helianthus annuus L., Cosmos sulphureus Cav., Cosmos...     

Effects of T-2 toxin on histopathology,fatty acid and water distribution of shrimp (Litopenaeus vannamei) muscle

T-2 toxin (T-2), one of the naturally occurring mycotoxins, often accumulates in aquatic animals from contaminated feed. Shrimp (n?=?30 per group) were fed with different concentrations (0, 0.5, 1.5, 4.5 and 13.5?mg kg^?1) of T-2 for 20?days. Changes in histopathology, fatty acid and water distribution of shrimp muscle were analyzed. Histopathology of shrimp muscle showed dose-dependent marked degenerative and necrotic changes on exposure to dietary T-2. The T-2 significantly (P?<?0.05) affected the muscle fatty acid composition. ∑SFA, ∑MUFA and ∑PUFA initially decreased and then increased slowly in the high-dosed groups. C16:0, C18:1n-9 and C18:2n-6 were the main saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), respectively. Also, T-2 significantly affected water distribution in shrimp muscle. High doses of T-2 reduced free water content, resulting in a reduction in the water holding capacity and hence changes to the shrimp muscle quality. Collectively, these results illustrated that T-2 significantly affects the fatty acid and water distribution, and also muscle histopathology, all of which would result in a reduction in the quality and nutritional value of shrimp.     

Synthesis of branched allylic sulfones by regioselective boron-catalysed hydrosulfonylation

Environmental Chemistry Letters - Branched allylic sulfones are scaffolds widely distributed in bioactive molecules and organic functional materials. The synthesis of allylic sulfones has been...     

神农架大九湖亚高山泥炭湿地甲烷通量变化特征及其与产甲烷菌群落组成的关系

2018年12月～2019年11月,采用涡度相关法和高通量测序技术,以湖北省神农架大九湖亚高山泥炭湿地为研究对象,对甲烷(CH4)通量以及产甲烷菌群落组成进行相关研究.结果 及分析表明:大九湖泥炭湿地研究期间表现为CH4的源,CH4总排放量为9333.26 mg· m-2,CH4日平均排放通量为18.50 nmol·m-2·s-1,冬、春、夏、秋四季的CH4平均排放通量分别为6.46、4.62、36.81、25.92 nmol·m-2·s-1,存在明显的季节变化;研究区产甲烷菌优势菌群为Methanoregula(66.73％)和Methanocella(21.99％);对样本中产甲烷菌的Shannon指数进行双因素方差分析发现,同一季节不同深度的样本中产甲烷菌多样性存在显著差异,随着深度的增加,产甲烷菌的多样性指数呈下降趋势;同一深度不同季节的样本中产甲烷菌多样性存在显著差异;夏季产甲烷菌群落组成与CH4排放通量为强正相关关系,春季产甲烷菌群落组成与CH4排放通量为强负相关关系,Methanothermus与CH4排放通量为显著正相关关系,Methanolinea与CH4排放通量为显著负相关关系.     

Effects of exogenous acylated homoserine lactones on biofilms in biofilters for gaseous toluene treatment

● Biofilm formation was enhanced by exogenous AHLs. ● EPS production and microbial adhesive strength of biofilm were promoted. ● Exogenous AHLs improved the performance of biofilters treating toluene. Biofilters are typical biofilm reactors, and they usually have poor biofilm formation resulting in limited reactor performance. Exogenous acylated homoserine lactones (AHLs) can enhance biofilm formation in many bioreactors based on quorum sensing regulation. However, their effect on biofilm in biofilters utilized for volatile organic compound (VOC) removal is unknown and needs to be investigated. In this study, the effects of the exogenous AHLs on biofilters for gaseous toluene removal were investigated. Analysis of biofilms in biofilters showed that the addition of exogenous AHLs considerably enhanced biofilm growth; the average biofilm concentration increased by 18%. Furthermore, the average biofilm coverage proportions in biofilters with and without exogenous AHLs were 17 % and 13 %, respectively, demonstrating the positive effect of exogenous AHLs on biofilm coverage. In particular, exogenous AHLs promoted the production of extracellular polymeric substances and the microbial adhesive strength of the biofilm. In addition, the exogenous AHLs showed no significant effect on the gaseous toluene removal efficiency of the biofilter. These results show that exogenous AHLs can enhance biofilm formation and can guide the application of exogenous AHLs in VOC biofilters.     

聚苯乙烯/CdS/TiO_2双壳层核壳纳米颗粒可见光催化降解甲基橙

采用溶胶-凝胶法,在聚苯乙烯(PS)/CdS核壳纳米颗粒表面包覆致密TiO_2层,制备出具有双壳层结构的PS/CdS/TiO_2纳米复合颗粒,考察了制备条件对材料结构的影响,并利用甲基橙溶液对其光催化性能进行了评价。SEM、TEM、XRD和FTIR分析结果表明,制得的微球单分散性良好,壳层包覆完整,厚度均匀。PS/CdS/TiO_2制备的适宜反应时间为12~18 h,适宜反应pH为7~9。PS/CdS/TiO_2较PS/CdS具有更为优异的可见光催化性能。     

不同培养条件下锰过氧化物酶(MnP)的合成及其对甲基橙的降解

高效、大规模、低成本合成木质素降解酶是直接采用其降解难降解有机污染物所必须解决的问题.对锰过氧化物酶(MnP)降解甲基橙和在非灭菌的反应器中连续合成MnP的可行性进行考察.结果表明,在采用2 mmol H2O2和1.5 mmol MnSO4的降解体系中,获最大脱色效果,且100、200和300 U/L的MnP可在8h内将甲基橙分别脱色18％、23％和35％;在非灭菌的反应器水平上实现了固定化培养的P.chrysosporium连续23 d合成MnP,但MnP酶活仅为2～ 23 U/L,难以酶解甲基橙;然而,在摇瓶培养条件下固定化的P.chrysosporium合成的MnP却能达1 152 U/L.因此,直接采用MnP对污染物进行降解以及在非灭菌的反应器中持续合成MnP是可行的,但就在非灭菌条件下如何提高MnP的合成量还有待开展深入的研究.