Effects of petroleum contamination on soil microbial numbers, metabolic activity and urease activity

The influence of petroleum contamination on soil microbial activities was investigated in 13 soil samples from sites around an injection water well (Iw-1, 2, 3, 4) (total petroleum hydrocarbons (TPH): 7.5-78 mg kg⁻¹), an oil production well (Op-1, 2, 3, 4, 5) (TPH: 149-1110 mg kg⁻¹), and an oil spill accident well (Os-1, 2, 3, 4) (TPH: 4500-34 600 mg kg⁻¹). The growth rate constant (μ) of glucose stimulated organisms, determined by microcalorimetry, was higher in Iw soil samples than in Op and Os samples. Total cultivable bacteria and fungi and urease activity also decreased with increasing concentration of TPH. Total heat produced demonstrated that TPH at concentrations less than about 1 g kg⁻¹ soil stimulated anaerobic respiration. A positive correlation between TPH and soil organic matter (OM) and stimulation of fungi-bacteria-urease at low TPH doses suggested that TPH is bound to soil OM and slowly metabolized in Iw soils during OM consumption. These methods can be used to evaluate the potential of polluted soils to carry out self-bioremediation by metabolizing TPH.     

Occurrence of polychlorinated biphenyls (PCBs) together with sediment properties in the surface sediments of the Bering Sea, Chukchi Sea and Canada Basin

The spatial distribution and potential source of polychlorinated biphenyls (PCBs) in surface sediments from Bering Sea, Chukchi Sea, and Canada Basin and the relationship between PCBs and sedimentary properties including grain size, water content, loss on ignition, total organic carbon, and black carbon were explored. ΣPCBs (the sum of the detected PCB congeners) concentrations fluctuated in the study area, ranging from 22-150, 60-640 and 24-600 pg g(-1) dry weight for the Bering Sea, Chukchi Sea, and Canada Basin. A similar homologue pattern was observed at different locations, with tri-chlorinated PCBs being the dominant homologue, implying that the PCBs came mainly from the atmospheric transportation and deposition and ocean current transportation. No apparent co-relationships between PCB concentrations and sediment properties were obtained, indicating that the distribution of PCBs was not only controlled by their source, but also by the multi-factors such as atmospheric transport and depositing, mixing, partitioning and sorption in the water column and sediments.     

Potential mechanisms of phthalate ester embryotoxicity in the abalone Haliotis diversicolor supertexta

The effects and associated toxicological mechanisms of five phthalate esters (PAEs) on abalone embryonic development were investigated by exposing the embryos to a range of PAEs concentrations (0.05, 0.2, 2 and 10 μg/mL). The results showed that PAEs could significantly reduce embryo hatchability, increase developmental malformations, and suppress the metamorphosis of abalone larvae. The possible toxicological mechanisms of PAEs to abalone embryos included, affecting the Na⁺-K⁺-pump and Ca²⁺-Mg²⁺-pump activities, altering the peroxidase (POD) level and the malondialdehyde (MDA) production, damaging the extraembryonic membranes structure, as well as disrupting endocrine-related genes (gpx, cyp3a, and 17β-hsd 12) expression properties. Taken together, this work showed that PAEs adversely affected the embryonic ontogeny of abalone. The abilities of PAEs affecting the osmoregulation, inducing oxidative stress, damaging embryo envelope structure, and causing physiological homeostasis disorder, are likely to be a part of the common mechanisms responsible for their embryonic toxicity.     

7种水生植物去除城市生活污水氮磷效果的研究

在对南方地区水生植物全面了解的基础上,选择凤眼莲、长鬃蓼、美人蕉、短叶茳芏、鸭趾草、空心莲子草和风车草7种南方地区最常见的水生植物作为研究对象,分别从7种水生植物对城市生活污水中NH3-N、TN和TP等污染的净化效果进行研究,结果表明,7种植物对生活污水中的NH3-N、TN和TP等污染成分都有一定的去除效果,其中凤眼莲...     

催化型微粒捕集器的再生与压降数值研究

采用新的再生机理对催化型微粒捕集器（CPF）深床捕集微粒的氧化再生过程进行了建模,并将微粒捕集器中的压降分成5个部分分别计算,对其压降特性进行了数值研究。结果表明,新模型对深床捕集微粒的氧化再生计算与实验值吻合良好,比原模型更能反映微粒沉积的实际过程,深床捕集微粒的压降计算值也更精确。在排气流量大、温度高的工况下,深床捕集微粒的压降先迅速增大再减小的现象明显。研究结果能为工程应用提供验证手段,为CPF的优化设计提供依据。     

Application of a DPSIR Modeling Framework to Assess Spatial–Temporal Differences of Water Poverty in China

Water shortage is a common problem around the world, especially in developing countries. Water shortage is closely linked to natural and social conditions, but the linkages between these natural and social conditions and their underlying temporal and spatial variation are less well explored. This paper details an application of the Driving‐Force‐Pressure‐State‐Impact‐Response (DPSIR) model, a holistic and sustainable tool for resources planning and management, and uses comprehensive weights to evaluate the water poverty (wp) in China from 1997 to 2014. This study applies the Kernel density estimation model to analyze the temporal variation trend and uses the least square error model to analyze the spatial pattern of wp. The results show the level of wp is gradually declining over time and the improvements in the coastal and inland wp situation are not spatially harmonious, and there are four primary types of wp in China based on drivers and causal mechanisms: D‐P‐I, D‐P‐I‐R, D‐P‐S‐I, and D‐P‐S‐I‐R. Furthermore, we analyze the main causes of spatial difference of wp and put forward corresponding countermeasures. The research findings are intended to provide a new insight for the evaluation of wp in the context of sustainable development, breaking past limitations that arise in simplified analyses using a single method, and to provide a strategy for regional water resources management to relieve wp.     

电凝并式空气净化单元对颗粒物和甲醛净化效果的实验

研究一种新型电凝并式空气净化单元对室内空气中颗粒物和甲醛的净化效果.实验结果表明,高压高频(HV-HF)电凝并装置能促使小粒子相互凝并为较大的电中性的粒子团,这些具有较高比表面积的电中性粒子团进入室内空间,能继续粘附空气中及物体表面上的颗粒,形成更大的粒子团,从而易于被净化单元中的中效过滤器捕集,而且该净化单元对于大粒子(粒径＞0.7μm)浓度较高的场所净化效果更加明显.另外,室内空气中吸附在颗粒物表面的甲醛也随之被高效去除.该净化单元的投入使用,起到了提高过滤效率、去除气溶胶小粒子、降低能耗、进一步改善室内空气品质等多重功效.     

沸石生物联合吸附再生工艺参数优化研究

简述了沸石生物联合吸附再生工艺(ZCS工艺)的工艺原理,选取了影响沸石生物联合吸附再生工艺污水处理效果的影响因素,通过正交实验,优化了工艺的运行参数.在优化结果为泥龄(SRT)40 d、沸石投加量16.8 g/L、外回流比(R)1、内回流比(r)1、A池碳源投加比(m)0、吸附池溶解氧(DO吸)1 mh/L和O池溶解氧(DOO)2 mg/L的条件下稳定运行后,出水水质达到《城镇污水处理厂污染物排放标准》(GB18918-2002)中一级B标准的要求.     

粉煤灰/污泥烧结陶粒的研制与应用

以粉煤灰和工业污水处理站的剩余污泥为主要原材料,采用烧结法研制复合陶粒.分析了不同配方和不同烧结温度对陶粒性能的影响,以陶粒吸水率、容重为评价指标确定最佳配比和最佳烧结温度,并对陶粒用于铺设景观水底、治理城市水体进行了可行性分析.粉煤灰/污泥陶粒的容重为0.79～0.90 g/m3,吸水率为68.95%～80.01%.陶粒对水中氨氮和总磷吸附容量分别为0.03～0.05 mg/g和0.01～0.02 mg/g.     

冀西北半干旱区等高植物篱面源污染控制机理

坡面养分流失是造成面源污染的主要形式.本研究利用冀西北黄土丘陵区的试验小区的长年观测资料,并结合野外全坡面大型人工模拟降雨试验及室外实验数据,分析了冀西北温带及半干旱地区等高植物篱对面源污染控制机理,得出在暴雨条件下细沟产生并导致侵蚀剧烈增加的临界坡长为10～15m;研究揭示出冀西北半干旱区面源污染形态以泥沙携带养分流失为主,等高植物篱控制面源污染的途径是控制土壤颗粒中的养分流失.