DEHP与OVA联合染毒对小鼠肺功能和肺部IL-17表达的作用

为探讨邻苯二甲酸二乙基己酯(di-(2-ehtylhexyl)phthalate,DEHP)在单独染毒和与卵清蛋白(ovalbumin,OVA)联合染毒条件下对小鼠气道的影响及其相关机制,将Balb/c小鼠随机分为:未处理对照组(生理盐水组)、DEHP染毒组、OVA染毒组、DEHP+ OVA联合染毒组(DEHP+ OVA),每组雄性Balb/c小鼠6只.用OVA致敏加激发的方式制作小鼠哮喘模型.DEHP染毒组每天给予10 mg·kg-1 DEHP灌胃,连续54 d.OVA染毒组、DEHP+ OVA染毒组小鼠均在第54～60 d(共计1周)进行1％ OVA雾化(30 min·d-1),每日1次,诱发哮喘.第60 d进行以下操作:肺功能测试,肺泡灌洗液(bronchoalveolar lavage fluid,BALF)样品收集和肺组织中的Interleukin-17A(IL-17A)含量的测定.结果显示,与DEHP染毒组相比,DEHP与OVA联合染毒组小鼠BALF的IL-17A显著增加(p＜0.05),肺功能降低(p＜0.05),气道重塑,肺部细胞浸润明显.提示DEHP对小鼠哮喘模型佐剂作用的分子机制可能涉及IL-17的介导作用.     

Investigation of oil vapor emission and its evaluation methods

In oil operations such as storage, loading, and unloading, there are many chances for oil vapor to be emitted from tanks, tankers or truck tanks into the air. Oil vapor emission (OVE), having serious harmful effects on people and the environment, is always an important research topic for scientists, engineers or managers engaged in the fields of oil production and transportation, fire prevention, and environmental protection. As the second greatest oil consuming country in the world, China has particular interests in investigating ways to better methods to realize and then control the OVE. In this paper, three evaluation methods for the OVE are introduced and summed up. In particular, a set of self-founded OVE’s appraisement methods, which work by theoretical deduced equations integrated with both a software PELES-2.0 and a simple correction method, was systematically investigated. This appraisement system can conveniently and accurately be applied to evaluate the OVE, and further it can also provide base references and/or guides for the law makers, enterprise managers and equipment developers in controlling OVEs.     

长江中下游浅水湖泊沉积物对磷的吸附特征

研究了长江中下游浅水湖泊1 1个沉积物对磷的吸附等温线及其吸附动力学,并分析了沉积物理化特征对磷吸附特征的影响,研究发现:①沉积物对磷酸盐的吸附主要在前1 0h内完成,在0.5h内吸附反应十分迅速,并逐渐达到吸附平衡;②沉积物本底吸附态磷与其有机质、CEC、总磷、无机磷、有机磷、Fe/Al 磷和总氮显著正相关;对磷酸盐的最大吸附量与其CEC和无机磷、有机质和总磷呈显著负相关;而总最大吸附磷量与其有机质、CEC、总磷、无机磷、有机磷、Fe/Al 磷和总氮含量呈显著正相关;③就目前长江中下游浅水湖泊的水质而言,其沉积物存在解析;沉积物对磷酸盐的吸附 解吸平衡浓度与其有机质,CEC ,总氮,总磷以及各形态磷含量均有显著的正相关关系.本研究条件下,即使是污染较为严重的湖泊,其沉积物也具有向上覆水体释磷酸盐的趋势.     

HITNP同步除磷脱氮新工艺

HITNP同步除磷脱氮新工艺采用复合式活性污泥生物膜系统,避免了硝化菌和聚磷菌的污泥龄矛盾.利用反硝化除磷的“一碳两用”缓解原水碳源不足的矛盾.通过独特的硝化液回流方式,使全部污泥经历了释磷和聚磷循环,厌氧池污泥浓度是缺氧池污泥浓度的1.5～2倍,对进水中的大分子有机物降解效果好,厌氧池COD的去除率高,强化系统的除磷能力.以低碳氮比的生活污水为处理对象,长期的运行结果表明,该工艺出水中的总磷、氨氮、总氮和COD的去除率分别为91.1% 、88.7%、58.1%和88.6%.出水水质平均值为磷0.27 　mg/L,氨氮1.74 　mg/L,总氮17.30 　mg/L和COD 24.38 　mg/L.HITNP同步除磷脱氮新工艺具有稳定的同步除磷脱氮效果,出水达到国家城市污水厂污染物排放标准GB18918-2002一级B标准要求.     

污泥中磷的形态与生物可利用磷的分布及相互关系

应用SMT法(The Standards, Measurements and Testing Programmed)对南京市江心洲污水处理厂不同处理阶段污泥中磷的形态进行了分析,揭示了污泥中生物有效磷的可利用性和迁移性.结果表明,污泥中的磷主要以无机磷(IP)的形态存在,占总磷(TP)的61%以上;有机磷(OP)含量较低,仅为15%-35%;而在无机磷中,非磷灰石无机磷(NAIP)是主要的赋存形态,占IP的60%以上.这表明污泥中的磷具有较高的潜在生物可利用性. TP与NAIP OP呈极显著的正相关关系(R2=0.9607, p<0.01),表明在不具备磷形态分析的情况下,可以通过TP的测定来预测污泥中磷的潜在生物有效性.污泥的理化性质和磷形态含量的相关分析表明,有机质和pH是污泥理化性质中的重要指标,对污泥中磷的潜在环境行为具有重要影响.     

人工湿地硝化与反硝化细菌分布研究

试验通过考察水生蔬菜型垂直潜流湿地中硝化细菌、反硝化细菌的数量和分布情况．得出在现工艺的人工湿地中,硝化菌和反硝化菌满足一定的分布规律。硝化细菌和反硝化细菌数量的不同分布特点使人工湿地中形成上、下分层的硝化与反硝化活性区域。     

Biological treatment of chicken feather waste for improved biogas production

A two-stage system was developed which combines the biological degradation of keratin-rich waste with the production of biogas. Chicken feather waste was treated biologically with a recombinant Bacillus megaterium strain showing keratinase activity prior to biogas production. Chopped, autoclaved chicken feathers (4%, W/V) were completely degraded, resulting in a yellowish fermentation broth with a level of 0.51 mg/mL soluble proteins after 8 days of cultivation of the recombinant strain. During the subsequent anaerobic batch digestion experiments, methane production of 0.35 Nm³/kg dry feathers (i.e., 0.4 Nm³/kg volatile solids of feathers), corresponding to 80% of the theoretical value on proteins, was achieved from the feather hydrolyzates, independently of the pre-hydrolysis time period of 1, 2 or 8 days. Cultivation with a native keratinase producing strain, Bacillus licheniformis resulted in only 0.25 mg/mL soluble proteins in the feather hydrolyzate, which then was digested achieving a maximum accumulated methane production of 0.31 Nm³/kg dry feathers. Feather hydrolyzates treated with the wild type B. megaterium produced 0.21 Nm³ CH₄/kg dry feathers as maximum yield.     

Evidence for coupled iron and nitrate reduction in the surface waters of Jiaozhou Bay

Iron and nitrate (NO₃^?) are dominant physiologically required nutrients for phytoplankton growth, and iron may also play a key role in the marine nitrogen cycle. In this study, we investigated the temporal and spatial distributions of dissolved iron (DFe) and Fe(II) in the surface waters of Jiaozhou Bay (JZB) from April 2 to July 26, 2017. High concentrations of DFe and Fe(II) predominantly occurred in nearshore and estuarine stations and concentrations were generally higher in April and May. The highest DFe concentration was observed along the coast of Hongdao (51.55 nmol/L) in May, while the lowest concentration was observed in the western coastal region (2.88 nmol/L) in April. The highest and lowest Fe(II) concentrations were observed in the Licun estuary (22.42 nmol/L) and outer bay (0.50 nmol/L) in May, respectively. We calculated the proportions of nitrate, nitrite, and ammonium in dissolved inorganic nitrogen (DIN) as well as the ratio of Fe(II) to DFe in all four months. The mean Fe(II)/DFe ratio was 0.48 in April, 0.43 in May, 0.69 in June, and 0.32 in July. The mean ratio of NO₃^? to DIN was 0.78 in April, 0.54 in May, 0.20 in June, and 0.62 in July. NO₃^?/DIN continuously decreased in the first three months, while Fe(II)/DFe remained high, which suggests that the reduction of iron and nitrate occurred simultaneously in the surface waters of JZB.     

基于间歇饥饿的SNAD工艺运行

在室温下(22℃±3℃)用SBR反应器运行SNAD工艺,通过定期延长系统水力停留时间,营造间歇饥饿环境,探讨间歇饥饿策略下SNAD工艺的运行情况.结果表明,系统经过间歇饥饿运行后,好氧阶段末的NO_3~--N浓度降至8. 72 mg·L~(-1),亚硝酸盐积累率达到83. 18%,表明NOB活性得到了有效抑制,实现了亚硝化性能的提高;系统经过间歇饥饿运行后,好氧阶段末的亚氮与氨氮基质的比例得到调整,为后续厌氧氨氧化过程提供了合适底物,使出水氨氮浓度降至1. 0 mg·L~(-1)以下,同时由于出水硝氮浓度降低,总氮去除率达到了92. 07%左右,系统处理性能提高;通过测定功能菌活性,发现饥饿后亚硝化性能提高的主要原因是饥饿期AOB活性衰减速率低于NOB及恢复期前期AOB活性恢复速率显著高于NOB.     

重庆老龙洞地下河流域氮、磷及微生物污染调查研究

随着城镇化不断发展,我国地下水普遍遭受了不同程度的污染,尤其是西南岩溶区地下水是当地重要的水源,一旦遭受污染将很难恢复.本研究选取NO-3、PO34、NH+4和总细菌(total coliform)、大肠杆菌(total E.coli)、粪大肠杆菌(fecal coliform)作为指标,对重庆南山老龙洞流域进行多年来的调查研究.结果表明,老龙洞流域地下水NO-3、NH+4、PO3-4含量均超过天然水规定值,尤其以NH+4、PO3-4污染较为严重.桂花湾泉NO-3含量为19.78~68.55 mg·L-1,有的月份超过了世界卫生组织规定的标准50 mg·L-1.老龙洞出口NH+4、PO3-4含量分别为2.71~12.92 mg·L-1、0.16~11.22 mg·L-1,是污染最重的地下水.老龙洞地下河NO-3含量低于岩溶表层泉,而NH+4、PO3-4含量则高于表层岩溶泉.城镇化的发展、农田减少以及洞内还原环境是导致老龙洞地下河NO-3含量从2008~2013年降低的原因,而高PO3-4含量污水不断输入地下河使得老龙洞地下河PO3-4含量呈增加趋势.微生物污染极为严重,甚至远超过中国地下水和饮用水规定的Ⅴ类标准,以粪大肠菌为例,地下水中其含量波动范围为3.4×104~3.68×104CFU·mL-1.岩溶区由于特殊的水文地质结构,岩溶洼地、天窗、落水洞导致岩溶地下水极易遭受到污染.农业活动、城镇、企业和居民点生产生活排污,是地下水氮、磷和微生物污染的主要来源.