南京冬季气溶胶光学特性及黑碳光吸收增强效应

2016年1月1~19日在南京北郊利用三波长光声黑碳光度仪(PASS-3)对气溶胶的光学性质进行了实时在线观测,同时结合气溶胶化学组成分析了黑碳气溶胶的光吸收增强效应.结果表明,观测期间气溶胶在532 nm下的吸收系数、散射系数、单散射反照率的平均值为(64.19±35.28)Mm-1、(454.68±238.71)Mm-1、0.87±0.03,受边界层高度及颗粒物浓度的影响,呈现出明显的日变化特征.黑碳气溶胶的质量吸收截面(MAC)在观测期间的变化趋势为前期低,后期高,与非EC组分相对EC比值的变化趋势一致,受不同污染条件下二次物质的占比及覆盖物厚度变化的影响.基于MAC计算得到的405、532、781nm下的光吸收增强(EMAC)平均值分别为1.53±0.56、1.34±0.47、1.14±0.40,随着波长增加而降低,存在棕色碳(Br C)的贡献.各非EC组分相对EC的比值与EMAC均有一定相关性,其中OC/EC与EMAC相关性最高,说明有机物的积累是导致黑碳光吸收增强的主要原因.K+/EC与EMAC的高相关性表明生物质燃烧过程对光吸收增强也有一定影响.     

生物表面活性剂产生菌的分离鉴定及碳氮源优化

采集炼油厂内长期石油污染土壤,经富集培养、蓝色凝胶平板筛选和发酵液表面张力测定等方法,从油泥中筛选出产生物表面活性剂的土著微生物1株,命名为S2,并对其进行生理生化性能测定与产物特性及结构研究.结果表明,该菌鉴定为铜绿假单胞菌Pseudomonas aeruginosa,测定证明其发酵液表面张力稳定,最佳条件下发酵液表面张力可由75mN·m-1降至35mN·m-1,临界束胶浓度（CMC）值为0.25g·L-1,远远低于一般化学表面活性剂的CMC值.发酵液乳化性能优于对照的十二烷基磺酸钠(SDS)及十六烷基三甲基溴化铵(CTAB)等常用的化学表面活性剂.对培养基成分进行优化,选定的最佳碳源为菜油,最佳氮源为硝酸钠,优化培养条件后,产物最大产量达到了4.7g·L-1.     

生物炭对塿土土壤温室气体及土壤理化性质的影响

通过田间小区试验,分别向塿土土壤中添加0、20、40、60、80 t·hm~(-2)的苹果果树枝条生物炭后,分析了生物炭对土壤温度、土壤团聚体、NO_3~--N、NH_4~+-N、微生物量碳以及土壤温室气体排放的影响.结果表明,生物炭可以缓解土壤温度的变化,增加土壤大团聚体的数量,尤其是5 mm、5~2 mm和1~0.5 mm的团聚体数量.与对照相比,随着生物炭施用量的增加,土壤NO_3~--N、NH_4~+-N、微生物量碳分别增加了4.9%~33.9%、9.1%~41.1%和11.8%~38.5%.本研究中生物炭对土壤温室气排放的影响主要表现为:添加生物炭后,土壤CO_2的排放量以及CH_4的吸收汇分别增加了6.73%~23.35%和3.62%~14.17%;施用20 t·hm~(-2)和40 t·hm~(-2)的生物炭降低了土壤N_2O的排放和综合增温潜势(GWP),而当生物炭施用量大于等于60 t·hm~(-2)时反而增加了土壤N_2O的排放和综合增温潜势(GWP).说明生物炭作为一种土壤改良剂和碳减排剂,能够改善土壤质量,提高土壤肥力,提高农田土壤增汇减排的作用,此外,选择合适的生物炭施用量至关重要.     

UASB反应器快速启动的试验研究

在中温条件下投加颗粒活性炭可加快ＵＡＳＢ反应器颗粒化进程。通过对比试验,表明投加和不投加活性炭的反应吕处理石化石废水污泥颗粒化时间分别为３９ｄ和６２ｄ。投加活性炭反应器的颗粒污泥粒径也较大。最大ＣＯＤ去除率在８６％以上。并且投加活性炭反应器的有机负荷为不投加的２倍,运行效果更稳定。     

普光气田含硫污水尾气处理工艺应用与优化

针对中国石化普光气田产出水属于典型的含硫污水,密闭处理系统中产生大量高含硫尾气,论述了尾气处理工艺中存在的问题,优化了单一的生物除硫、活性炭吸附工艺,增加了一级碱洗、氧化除硫工艺,实现尾气达标排放。     

杭州黑碳气溶胶污染特性及来源研究

2011年7月~2012年6月对黑碳气溶胶(BC)、PM2.5、污染气体及气象因子进行同步观测,以评估杭州市BC污染特征、来源分布及对大气能见度的影响.结果表明:杭州市大气BC日均浓度范围为1.3~16.5μg/m3,年均值达到(5.1±2.5)μg/m3.BC呈明显的季节变化趋势,秋冬季高,夏季低.BC也呈典型的日变化趋势,交通高峰期高,下午低,同时与NOx呈较好的相关性,表明城市中BC受到机动车尾气排放的重要影响;而BC/CO低于其他城市则表明生物质燃烧排放可能是杭州BC的另一大重要来源.BC随风速下降呈上升趋势, BC超过10μg/m3的高浓度事件中,风速基本低于2m/s,北-西北-西风对高浓度BC的输送作用明显.观测期间BC的吸收系数为(44.8±23.0)Mm-1,占到总消光比例的10.4%.灰霾和重度灰霾天气下,吸收系数分别为(66.2±30.1),(100.2±49.2)Mm-1,达到非霾天气的2.2和3.4倍, 表明BC吸收消光作用是影响杭州市大气能见度下降和灰霾天气发生的重要因素之一.     

电化学微传感器检测水中痕量铜离子

为改善微电极在阳极溶出伏安法检测重金属离子过程中低电流响应和低电催化能力的缺点,提出了一种在碳纤维微电极表面合成还原氧化石墨烯/纳米金材料制得还原氧化石墨烯纳米金修饰碳纤维微电极（rGO/AuNPs CFMEs）的方法.通过SEM表征,所制备的rGO/AuNPs CFMEs具有比表面积高、吸附能力强和催化活性好的特点,因此改性微电极适合作为方波阳极溶出伏安法（SWASV）测定水中铜离子（Cu²⁺）的工作电极.在构建微传感器测试水中痕量铜离子系统后,对pH值、电导率、富集时间和富集电位等检测条件进行了优化.在pH值为4,电导率为36.1S/m,富集时间为360s,富集电位为-1.2V的最佳条件下,铜的线性范围和检出限分别0~1.0μmol/L和2.4nmol/L.此外,微传感器的可重复性、长期稳定性以及选择性也得到了验证.     

黑色金属材料在长江淡水中的腐蚀行为

通过现场暴露试验,获得了2种碳钢、3种不锈钢及1种不锈钢与碳钢复合板材料在武汉长江淡水中的4年腐蚀试验结果,总结了它们的腐蚀行为。结果表明,Q235和16Mn碳钢在武汉长江中有较高的腐蚀率和明显的点蚀,稳定腐蚀率为0.055 mm/a;暴露4 a,奥氏体不锈钢304和316L没有明显腐蚀,而马氏体不锈钢430有较明显的点蚀和缝隙腐蚀;马氏体不锈钢0Cr13Ni5Mo与Q345C复合钢板在长江淡水中使用4 a后,0Cr13Ni5Mo发生严重的点蚀,说明马氏体不锈钢在淡水中的应用应慎重。     

Pd-MnO2 nanoparticles/TiO2 nanotube arrays (NTAs) photo-electrodes photo-catalytic properties and their ability of degrading Rhodamine B under visible light

Pd-MnO_2/TiO_2 nanotube arrays(NTAs) photo-electrodes were successfully fabricated via anodization and electro deposition subsequently; the obtained Pd-MnO_2/TiO_2 NTAs photo electrodes were analyzed by scanning electron microscopy(SEM), X-ray diffraction(XRD) and characterized accordingly. Moreover, the light harvesting and absorption properties were investigated via ultraviolet–visible diffuse reflectance spectrum(DRS); photo degradation efficiency was investigated via analyzing the photo catalytic degradation of Rhodamine B under visible illumination(xenon light). The performed analyses illustrated that Pd-MnO_2 codoped particles were successfully deposited onto the surface of the TiO_2 nanotube arrays;DRS results showed significant improvement in visible light absorption which was between400 and 700 nm. Finally, the photo catalytic degradation efficiency results of the designated organic pollutant(Rhodamine B) illustrated a superior photocatalytic(PC) efficiency of approximately 95% compared to the bare TiO_2 NTAs, which only exhibited a photo catalytic degradation efficiency of approximately 61%, thus it indicated the significant enhancement of the light absorption properties of fabricated photo electrodes and their yield of UOH radicals.     

Mesoporous carbon nanomaterials induced pulmonary surfactant inhibition, cytotoxicity, inflammation and lung fibrosis

Environmental exposure and health risk upon engineered nanomaterials are increasingly concerned. The family of mesoporous carbon nanomaterials(MCNs) is a rising star in nanotechnology for multidisciplinary research with versatile applications in electronics,energy and gas storage, and biomedicine. Meanwhile, there is mounting concern on their environmental health risks due to the growing production and usage of MCNs. The lung is the primary site for particle invasion under environmental exposure to nanomaterials. Here, we studied the comprehensive toxicological profile of MCNs in the lung under the scenario of moderate environmental exposure. It was found that at a low concentration of 10 μg/mL MCNs induced biophysical inhibition of natural pulmonary surfactant. Moreover, MCNs at similar concentrations reduced viability of J774 A.1 macrophages and lung epithelial A549 cells.Incubating with nature pulmonary surfactant effectively reduced the cytotoxicity of MCNs.Regarding the pro-inflammatory responses, MCNs activated macrophages in vitro, and stimulated lung inflammation in mice after inhalation exposure, associated with lung fibrosis.Moreover, we found that the size of MCNs played a significant role in regulating cytotoxicity and pro-inflammatory potential of this nanomaterial. In general, larger MCNs induced more pronounced cytotoxic and pro-inflammatory effects than their smaller counterparts. Our results provided valuable information on the toxicological profile and environmental health risks of MCNs, and suggested that fine-tuning the size of MCNs could be a practical precautionary design strategy to increase safety and biocompatibility of this nanomaterial.