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391.
非典型环境案件法律适用问题初探 总被引:1,自引:0,他引:1
代杰 《中国环境管理干部学院学报》2012,22(3):1-4
实践中一些非典型环境案件的法律适用问题存在争议。对此,必须明确:生态破坏侵权属于一般侵权行为,应当适用《侵权责任法》对一般侵权行为的规定;家庭生活污染和劳动环境污染属于环境污染,受害者在法律适用上有选择权;室内装修污染不属于环境污染,其责任属于产品责任,不适用环境污染侵权规则。 相似文献
392.
代伟 《中国环境管理干部学院学报》2012,(1):69-71
针对传统教学方法存在的问题,在《营销统计》课程教学实践中采用"教学做"一体化教学模式,构建了"一条主线、两个知识模块、三种关键能力"的教学内容体系,将统计调查工作设置为一个实训项目,形成"一个项目四个环节"的教学过程。 相似文献
393.
代伟 《中国环境管理干部学院学报》2012,22(3):73-75
OBTL模式是以明确的目标和成果为导向,以学生为中心,以培养学生适应未来岗位要求的能力和素质为根本目的的教育模式。借鉴OBTL教学模式及其理念,依据市场营销专业的人才培养目标,确立了数据处理能力、案例分析能力和数学建模能力的能力目标,设计相匹配的多种数学实践活动,并构建多元化评估体系,旨在增强教学的针对性和实效性,提升高职学生的数学应用能力。 相似文献
394.
Li J Liu X Liu Y Ramsay J Yao C Dai R 《Environmental science and pollution research international》2011,18(9):1567-1573
Introduction
This study investigated the effect of copper on chemical oxygen demand (COD) removal efficiency and on the properties (mainly settling and dewatering) and the composition of extracellular polymeric substances (EPS) when 20 mg/L Cu(II) was continuously dosed to a sequencing batch reactor (SBR) inoculated with activated sludge. 相似文献395.
Liting Yang Chunlan Dai Lijun Ma Shaoquan Lin 《Journal of Polymers and the Environment》2011,19(1):189-195
The conjugated soybean oil was synthesized through the isomerization reaction of soybean oil to transformed the structure
of linoleic acid into conjugated linoleic acid structure, and Rhodium complexes (RhCl(Pph3)3) was used as catalyst. The efficiency on the conjugation of catalyst RhCl (Pph3)3, tin dichloride dehydrate (SnCl2·2H2O) and triphenylphosphine (Pph3) were evaluated. The results showed when RhCl(Pph3)3, SnCl2·2H2O and Pph3 are 9.25, 9.0 and 13.1 mg in 100 g soybean oil respectively, the highest conversion of conjugation achieved 96%. The free
radical copolymerization of conjugated soybean oil with acrylonitrile (AN) and dicyclopentadiene (DCP) was studied. AIBN was
used as the initiator. FT-IR and 1H-NMR results indicates that the conjugated soybean oil with AN and DCP did occur free radical copolymerization with the initiator
AIBN. The product is light yellow powder. The thermal properties of the soy-based copolymer were investigated by TG and DSC.
The initial degradation temperature of polymers is higher then 250 °C. 相似文献
396.
The biosorption of lead(II) ions in both simulated and real wastewater by spent mushroom Tricholoma lobayense, was studied in this work. The results show a biomass with a high potential for removing lead ions from wastewater. The optimum pH for the adsorption is 4, and the adsorption process is fast. The best sorbent mass of the biomaterial is 5 g/L with an initial lead(II) concentration of 1 mmol/L. The process follows the Langmuir isotherm model, and the biosorption capacity of lead ions reaches to 210 mg/g, which is higher than many biosorbents previously studied. The mechanism of biosorption may be mainly attributed to ion exchange. The FT-IR study identifies the functional groups responsible for this process. A scanning electron microscope showed a significant change of the sorbent surface after the biosorption process. The energy dispersive elemental analysis also confirmed the adsorption of lead(II) ions. 相似文献
397.
Fullerenes are set to be produced on an industrial scale in anticipation of their wide applications. This calls for research on their environmental and health impacts. This study investigates and compares the cell toxicity of different aqueous fullerene aggregates. Popular C60 dispersal methods were used to prepare four types of nC60 aggregates. These aggregates were tested against the indicator species Escherichia coli (E. coli) AMC 198. With aggregates of around 150 nm in diameter, the THF/nC60 suspension was very toxic and gave rise to a half maximal effective concentration (EC50) of 0.54 mg L−1 in E. coli. By contrast, the Tol/nC60 suspension exhibited a cytoprotective role while the Aqu-N2/nC60 and Aqu-O2/nC60 suspensions enhanced the metabolism of E. coli. Although some toxicants, such as THF and THF-peroxide, were introduced into the THF/nC60 suspension during the dispersion, the toxicity of nC60 itself cannot be neglected. 相似文献
398.
Anthocyanins inducibly synthesized by Cd treatment showed high antioxidant activity and might be involved in internal detoxification mechanisms of Azolla imbricata against Cd toxicity. In order to understand anthocyanin biosynthesis mechanism during Cd stress, the cDNAs encoding chalcone synthase (CHS) and dihydroflavonol reductase (DFR), two key enzymes in the anthocyanin synthesis pathway, were isolated from A. imbricata. Deduced amino acid sequences of the cDNAs showed high homology to the sequences from other plants. Expression of AiDFR, and to a lesser extent AiCHS, was significantly induced in Cd treatment plant in comparison with the control. CHS and DFR enzymatic activities showed similar pattern changes with these genes expression during Cd stress. These results strongly indicate that Cd induced anthocyanin accumulation is probably mediated by up-regulation of structural genes including CHS and DFR, which might further increase the activities of enzymes encoded by these structural genes that control the anthocyanin biosynthetic steps. 相似文献
399.
以废渣磷石膏为原料水热法制备硫酸钙晶须 总被引:1,自引:0,他引:1
以磷石膏为原料,采用水热法制备硫酸钙晶须。借助X射线衍射仪(XRD)、扫描电子显微镜(SEM)及红外光谱仪(FT-IR)等仪器对产物进行表征,研究了反应温度和时间、料浆初始固液比及不同添加剂等因素对产物形貌及可溶磷含量等的影响。结果表明,最佳反应条件为:反应温度140℃,反应时间2 h,料浆固液比为1∶10,最佳添加剂及剂量为丙三醇(V醇/V总液为50%)。所得产物为六方晶系的CaSO4.0.5H2O,直径1~3μm,晶须长径比为45左右,合成率约95%,产物可溶磷含量由原样的0.41%降至0.21%。 相似文献
400.
天然锰砂去除水中的砷 总被引:2,自引:0,他引:2
天然锰砂是一种廉价、高效的水处理用材料,但尚未用于水中砷的去除。实验研究了反应时间、砷形态、初始砷浓度、温度、溶液初始pH对吸附过程的影响。结果表明,天然锰砂对As(Ⅲ)的吸附能力大于As(Ⅴ)。25℃时,固液比为10 g/L的条件下,天然锰砂对初始浓度为5.0 mg/L的砷溶液吸附过程经72 h基本达到平衡,平衡时对As(Ⅲ)和As(Ⅴ)的去除率分别达到94.5%和85.9%。吸附过程符合Lagergren准一级反应动力学模型和假二级反应动力学模型。相比之下,假二级动力学模型拟合程度更高。对As(Ⅲ)和As(Ⅴ),45℃时的吸附量均大于25℃时。不同温度下,天然锰砂对As(Ⅲ)和As(Ⅴ)的吸附过程更符合Freundlich等温吸附模型。在溶液初始pH为3~10范围内,锰砂对砷的吸附能力受pH的影响较小。实验结果表明,天然锰砂是一种具有实际应用潜力的除砷材料。 相似文献