碳球负载四氧化三铁（Fe3O4／CNs）吸附Cu（Ⅱ）的性能研究米

利用水热法合成碳球（CNs）,原位生长四氧化三铁（Fe3O4）,通过SEM、XRD和FT—IR进行表征,研究碳球负载四氧化三铁（Fe3O4／CNs）对Cu（Ⅱ）的吸附性能,结果表明,当pH=6时,Fe3O4／CNs对Cu（Ⅱ）的去除率最大,吸附符合Langmuir等温方程,最大吸附量为44．08mgg。吸附动力学表明,Fe3O4／CNs对Cu（Ⅱ）的吸附符合准二级动力学方程。     

Chloronaphthalenes as food-chain contaminants: a review

Chloronaphthalenes are dioxin-like environmental and food contaminants that for many years have undergone diffusion from dispersed emission sources of various types on a global scale. When released into ambient air like many other semivolatile organohalogen compounds, chloronaphthalenes undergo various processes and pathways including sequestering by plant vegetation and biota. Recently available data indicate that sequestering rates of chloronaphthalenes by plant biomass and including edible plants as well as concentrations in food sources of plant origin can be greater than was earlier predicted. Additionally, it become known very recently that in some highly industrialized countries such as Japan, Canada and the UK, the technical chloronaphthalene mixtures are still a subject of industrial and commercial interest, even if such activities are illegal. Recent achievements in HRGC-HRMS have enabled elucidation and quantification of the chloronaphthalene congener composition in environmental matrices, food sources and technical mixtures, their persistency, environmental fate, accumulation in biota and potential for food chain biomagnification. However, at the same time this raised questions regarding human exposure to these compounds. By the late 1990s, these developments added to the relatively rapidly growing knowledge on these compounds and especially individual congener properties such as thermodynamic and physicochemical features and toxicity. Multistage fractionation has recently enabled routine congener-specific quantification of tetra- to octachloronaphthalene in various matrices. This paper reviews the literature on chloronaphthalenes as food chain contaminants and covers their origin, physicochemical properties, toxicity, environmental concentrations and persistency, and homologue group and congener composition in various matrices. The review also covers distribution in environmental compartments and subsequent fate and migration to food sources, as well as the magnitude of dietary intake and human body concentrations. Data on chloronaphthalene residues in food, however, are still scare, an exception being seafood sources and recently available data from Spain on their concentrations in staple foods and dietary intake.     

CNs−Bi12O17Cl2复合体系制备及光催化降解性能研究

采用简易水解法制备了一系列CNs−Bi₁₂O₁₇Cl₂复合半导体材料并对其物相、光学性质和光催化降解性能进行了分析表征。X射线衍射光谱表明复合体系衍射峰与四方晶相Bi₁₂O₁₇Cl₂一致,紫外可见漫反射光谱证明复合材料在可见区域具有较强的光吸收能力,由此可提高光催化活性。在可见光照射下,复合体系相对于纯Bi₁₂O₁₇Cl₂对亚甲基蓝具有更高的降解效率,特别是具有合适组分的样品CB50可以在180 min后完全去除20 mg·L⁻¹的亚甲基蓝分子,这主要是由于CNs的引入抑制了光生载流子的复合,使复合体系表现出更高的光催化降解性能。最后,提出了可能的光催化机理。