低温浓缩-气质联用分析污染源废气中环氧氯丙烷

建立了气袋采样-液氮低温浓缩-气质联用分析污染源废气中环氧氯丙烷的方法,优化了相关监测参数。优化后的方法在环氧氯丙烷质量浓度10~500μg/m~3范围内线性良好,相关系数0.999,加标回收率为72.1%~85.7%,相对标准偏差5%,气体进样量为5.0 mL时,检出限为4.37μg/m~3,可以满足废气中环氧氯丙烷监测的要求。     

实时荧光定量PCR法快速测定水中微囊藻

以铜绿微囊藻（Microcystis aeruginosa）16S rRNA基因片段为靶序列设计一对特异性引物,采用Real-time PCR法,对铜绿微囊藻进行定性、定量检测。试验表明,仅含铜绿微囊藻DNA模板的样品有特异性扩增,扩增产物熔解曲线平稳,峰尖且窄,熔解温度为（87±1）℃。以重组质粒pMD-18T-16S为标准品,检测区间为1．1×102 copies/mL～1．1×108 copies/mL,所得标准曲线符合制备实时定量PCR标准曲线的要求,对标准品进行测定,方法检出限为11 copies/mL。用该标准曲线对实验室培养获得的铜绿微囊藻DNA样品进行定量检测,与显微镜计数结果基本一致。     

Soil surface Hg emission flux in coalfield in Wuda,Inner Mongolia,China

Hg emission flux from various land covers, such as forests, wetlands, and urban areas, have been investigated. China has the largest area of coalfield in the world, but data of Hg flux of coalfields, especially, those with coal fires, are seriously limited. In this study, Hg fluxes of a coalfield were measured using the dynamic flux chamber (DFC) method, coupled with a Lumex multifunctional Hg analyzer RA-915+ (Lumex Ltd., Russia). The results show that the Hg flux in Wuda coalfield ranged from 4 to 318 ng m^?2 h^?1, and the average value for different areas varied, e.g., coal-fire area 99 and 177 ng m^?2 h^?1; no coal-fire area 19 and 32 ng m^?2 h^?1; and backfilling area 53 ng m^?2 h^?1. Hg continued to be emitted from an underground coal seam, even if there were no phenomena, such as vents, cracks, and smog, of coal fire on the soil surface. This phenomenon occurred in all area types, i.e., coal-fire area, no coal-fire area, and backfilling area, which is universal in Wuda coalfield. Considering that many coalfields in northern China are similar to Wuda coalfield, they may be large sources of atmospheric Hg. The correlations of Hg emission flux with influence factors, such as sunlight intensity, soil surface temperature, and atmospheric Hg content, were also investigated for Wuda coalfield.

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湖南省四水流域水沙周期特征及其影响因素分析

采用复小波变换和M K非参数检验的方法分析了湖南省四水流域主要控制站1951~2011年径流量与输沙量周期规律和突变特征。结果表明：(1)湖南四水径流量存在多个波动增加和波动减少的波动变化现象,但无显著变化趋势;而输沙量虽然有一定的波动,但总体上呈波动减少变化态势,而且下降趋势较显著;(2)湘潭站、桃江站和桃源站径流量和输沙量存在20~25 a的第一主周期,而石门站径流量和输沙量的第一主周期不具有一致性,径流量主周期为2 a,输沙量主周期为13 a,但其径流量和输沙量第二、三主周期变化规律相吻合,均为3~5 a的周期;(3)大量的水利工程建设是导致输沙量减少的主要原因,径流量的变化与降水的变化规律较为一致     

Degradation of the potential rodent contraceptive quinestrol and elimination of its estrogenic activity in soil and water

Quinestrol has shown potential for use in the fertility control of the plateau pika population of the Qinghai–Tibet Plateau. However, the environmental safety and fate of this compound are still obscure. Our study investigated degradation of quinestrol in a local soil and aquatic system for the first time. The results indicate that the degradation of quinestrol follows first-order kinetics in both soil and water, with a dissipation half-life of approximately 16.0 days in local soil. Microbial activity heavily influenced the degradation of quinestrol, with 41.2 % removal in non-sterile soil comparing to 4.8 % removal in sterile soil after incubation of 10 days. The half-lives in neutral water (pH 7.4) were 0.75 h when exposed to UV light (λ?=?365 nm) whereas they became 2.63 h when exposed to visible light (λ?>?400 nm). Acidic conditions facilitated quinestrol degradation in water with shorter half-lives of 1.04 and 1.47 h in pH 4.0 and pH 5.0 solutions, respectively. Moreover, both the soil and water treatment systems efficiently eliminated the estrogenic activity of quinestrol. Results presented herein clarify the complete degradation of quinestrol in a relatively short time. The ecological and environmental safety of this compound needs further investigation.     

Iron improving bio-char derived from microalgae on removal of tetracycline from aqueous system

Novel magnetic carbonaceous bio-char was hydrothermal prepared from microalgae under different loadings of iron and its structures and surface chemistry were characterized with Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and nitrogen adsorption-desorption isotherm (BET). The morphology of bio-char changed from sheet to particle as iron loading increased and its surface area also increased. When 3.0 g of dried microalgae and 6.0 mmol iron salt ((NH₄)₂SO₄·FeSO₄·6H₂O) were mixed and treated, the obtained bio-char possessing the highest amount of oxygen-containing functional groups resulted in the best adsorption performance on tetracycline (TC). This adsorption process was fitted to Langmuir adsorption isotherm and the maximum adsorption capacity was 95.86 mg/g, which is higher than other bio-char reported. The iron loading contributed to the higher adsorption capacity of bio-char, which may be due to three factors, the high surface area, more hydrogen bonding, and bridging effects of the structural Fe for TC. Our data suggest that bio-char may have more important role in stabilization of pollutants in the environment.     

The characteristics of nitrate removal by the psychrotolerant denitrifying bacterium Acinetobacter johnonii DBP-3, isolated from a low-temperature eutrophic body of water

A psychrotolerant denitrifying bacterial strain, DBP-3, was isolated from a eutrophic body of water by low-temperature-oriented acclimation culture. Based on its morphologicalandbiochemicalcharacteristics and 16S rDNA gene sequence, the bacterium was identified as belonging to the genus Acinetobacter and closely related to A. johnonii. The satisfactory growth of DBP-3 was observed at 10–30°C and pH 7–9. Strain DBP-3 was able to utilize three types of carbon sources (sodium acetate > sodium citrate > glucose) to support growth and denitrification. DBP-3 grew faster, but with lower nitrate removal efficiency and higher nitrite accumulation, under aerobic conditions than under anoxic conditions. DBP-3 was extremely susceptible to tetracycline and rifampicine and less sensitive to ampicillin and penicillin. The growth of DBP-3 was significantly affected by Hg (II), Cr (VI), Pb (II), Cd (II), and As (III) at 0.32, 0.63, 1.25, 2.5, and 25.0 mg L^?1, respectively. Interestingly, chromium (VI) significantly promoted DBP-3 growth at concentrations lower than 0.32 mg L^?1. These data may be helpful to support the use of strain DBP-3 in the purification of eutrophic water bodies at low temperatures.     

中性红在柚子皮上的吸附机制研究

采用柚子皮作为生物吸附材料吸附去除中性红。研究了中性红的初始浓度、吸附时间及反应温度对吸附效果的影响。结果表明,当中性红溶液从100 mg/L升高到250 mg/L时,反应95 min后,柚子皮对中性红的吸附量从16.80 mg/g增加到40.00mg/g。中性红在柚子皮上的吸附在60 min内基本上可以达到平衡,且柚子皮对中性红的吸附过程为放热过程;二级吸附动力学方程能更好地描述中性红在柚子皮上的吸附行为;中性红在柚子皮孔隙中的扩散不是唯一的吸附速率控制步骤,这个吸附过程可能受多个步骤共同控制;柚子皮对中性红的吸附是自发吸附,Langmuir、Freundlich和Temkin吸附等温式能很好地拟合柚子皮对中性红的吸附过程,拟合相关系数分别达到了0.991 8、0.993 4、0.989 0。     

中国海洋经济发展潜力分析

20世纪90年代以来,随着我国海洋经济的迅猛发展,海洋资源退化和海洋环境恶化已成为制约海洋经济可持续发展的"瓶颈"。因此,研究探讨海洋经济发展的潜力对于制定未来一段时期内我国海洋经济可持续发展战略具有重要意义。本文从海洋经济发展潜力的概念出发,以海洋资源分类为基础,综合考虑产业发展潜力和海洋环境生态损害造成损失,以较为合理的方法评估了我国海洋经济发展的潜力。海洋经济发展潜力是指海洋资源用于海洋开发和利用方面的潜在能力,具体计算时,应为海洋资源总价值扣除生态环境灾害造成损失后的价值。收益还原法是评估海洋经济发展的潜力的基本方法,对于不同的海洋资源潜力的评估采用的具体方法不同。本文分别核算了海洋渔业、海洋交通运输业、海洋石油天然气业、海洋盐业、滨海旅游业以及国际海底区域海洋经济的发展潜力,同时评估了未来我国海洋环境污染和海洋灾害的损失价值。结果表明:我国海洋经济发展潜力在199 737.16-320 335.57亿元,平均值为214 150.1亿元。