两广地区水域对酸雨的敏感性及其分区图

酸沉降对水生生态的影响程度,取决于降水中化学组分的输入量和地表水体对所输入的酸性物质的敏感性.湖泊对酸性沉降物影响的敏感性,决定于多种相互作用的因素,除酸沉降的强弱和影响酸沉降的气象因素外,还取决于湖泊的水文学及水化学性质、集水区的特点和土壤与基岩等诸因素.我国两广地区位于重酸雨区,酸雨频率高,酸度大,每     

用自旋捕集技术研究氟化物刺激人多形核白细胞呼吸爆发产生的活性氧自由基

用ESR波谱研究证明,F^-刺激人多形核白细胞（PMN）呼吸爆发产生活性氧自由基（O₂^-和·OH）,同时消耗O₂.用DMPO自旋捕集技术表明,在高浓度F^-刺激下PMN产生DMPO-OOH加合物;在低浓度F^-刺激下则产生DMPO-OH;在适中浓度F^-刺激下PMN先产生DMPO-OOH,随浓度降低变为DMPO-OH.用超氧化物歧化酶和过氧化氢酶的实验确定氧自由基主要来自O₂^-.用CTPO和CrOX的自旋探针测氧法证明,PMN受F^-刺激产生氧自由基时消耗的O₂是细胞外介质中的O₂.     

直筒式旋风脉冲静电除尘器性能研究

实验研究了电压、入口粉尘浓度和入口风速对直筒式旋风脉冲静电除尘器除尘效率的影响,测定了在不同入口风速下除尘器的分级效率.结果表明,脉冲供电能显著提高除尘器的除尘效率和分级效率,在脉冲电压为80 kV、入口粉尘质量浓度为5.0 g/m3N、入口风速为7～10 m/s时,除尘效率在99%以上,并在实验的基础上分析了脉冲供电下除尘器的除尘机理.     

吸烟烟气对鼠肺细胞膜的损伤和茶多酚的保护作用

本文以香烟气相物质作用鼠肺细胞膜为模型,用脂肪酸自旋标记物5-DOXYL和16DOXYL分别研究膜浅层和深层的动态性质受气相烟的影响,并用紫外可见分光光度法研究气相烟对膜脂的作用。结果发现,在实验的气相烟流量下,香烟气相物质能引发鼠肺细胞膜的脂质过氧化,并且使膜浅层的流动性增大。但对膜深层的动态性质没有明显的改变,如果在鼠肺细胞中预先加入粗晶态或粉态茶多酚。则肺细胞的过氧化和膜的动态性质改变受到抑制,而且这种抑制作用与茶多酚浓度呈量效关系,而茶多酚本身对膜浅层无明显作用,但对膜深层的流动性有一定影响,而且两种茶多酚的作用相似。     

Variation of airborne quartz in air of Beijing during the Asia-Pacific Economic Cooperation Economic Leaders' Meeting

Quartz particles are a toxic component of airborne paniculate matter(PM).Quartz concentrations were analyzed by X-ray diffraction in eighty-seven airborne PM samples collected from three locations in Beijing before,during,and after the Asia-Pacific Economic Cooperation(APEC) Leaders' Meeting in 2014.The results showed that the mean concentrations of quartz in PM samples from the two urban sites were considerably higher than those from the rural site.The quartz concentrations in samples collected after the APEC meeting,when the pollution restriction lever was lifted,were higher than those in the samples collected before or during the APEC meeting.The quartz concentrations ranged from 0.97 to 13.2 μg/m~3,which were among the highest values amid those reported from other countries.The highest quartz concentration exceeded the Californian Office of Environmental Health Hazard Assessment reference exposure level and was close to the occupational threshold limit values for occupational settings.Moreover,a correlation analysis showed that quartz concentrations were positively correlated with concentrations of pollution parameters PM_(10),PM_(2.5),SO_2 and NO_x,but were negatively correlated with O_3 concentration.The results suggest that the airborne quartz particles may potentially pose health risks to the general population of Beijing.     

不同负荷餐饮垃圾与城市厌氧污泥混合厌氧消化研究

本实验研究了不同有机负荷下,餐饮垃圾与消化污泥不同方式混合中温厌氧消化的过程。实验结果表明,1#-4#的酸化点均可逆,1#的酸化低值点为4.11,3#的为6.04,通过加入氢氧化钠溶液有效控制系统的酸化过程,防止出现酸抑制现象,使得各有机负荷均能进入正常的产甲烷阶段。1#-4#的单位生物气产量分别为0.18 L/gVs、0.85L/gVs、0.69L/gVs和0.44L/gVs,甲烷含量分别为56%、69%、57%和66%。混合厌氧消化后的剩余物比原消化污泥具有更好的生物降解能力。各负荷氨氮浓度在消化过程中的变化趋势一致,最高含量达1 183.28 mg/L。     

月湖底泥疏浚后底栖动物群落的恢复及其与环境的关系

研究对月湖底泥疏浚后底栖动物群落动态进行逐月的周年调查,并分析了底栖动物密度、生物多样性与环境因子的关系,结果表明：疏浚导致大型底栖动物基本消失,现存量从疏浚前的（4387±885）ind·m-2降低至（80±21）ind·m-2。疏浚后,寡毛类成为受干扰系统恢复过程中的先锋种类,在春季（4月）和秋冬之际（11月）出现2个密度高峰,分别为（1010±230）ind·m-2和（1538±408）ind·m-2,而摇蚊幼虫在疏浚一年后的秋冬季密度达到高峰（2021±612）ind·m-2,二者均基本恢复到疏浚前的密度水平。种类组成与疏浚前相似,优势种类数较疏浚前多,7月份以前,以霍甫水丝蚓占绝对优势,7月份以后以长足摇蚊占绝对优势。生物多样性在秋冬季恢复到疏浚前水平。寡毛类、摇蚊幼虫的密度、生物多样性与湖水溶氧、透明度呈显著正相关,与水体营养水平（TN、TP、有机碎屑）呈显著负相关（P〈0.05）。分析认为疏浚后底栖动物群落的季节变化与动物的生命周期（繁殖和生长）密切相关,而营养水平不是限制动物种群密度分布的主要因子。从底栖动物群落的恢复情况来看,疏浚后的底质环境更有利于底栖动物群落的生存和底栖生态系统的重建。     

Biosorption of Cu(II) to extracellular polymeric substances (EPS) from Synechoeystis sp.: a fluorescence quenching study

Biosorption of extracellular polymeric substances (EPS) from Synechocystis sp. (cyanobacterium) with Cu(II) was investigated using fluorescence spectroscopy. Three fluorescence peaks were found in the excitation-emission matrix (EEM) fluorescence spectra of EPS. Fluorescence of peak A (Ex/Em = 275/452 nm) and peak C (Ex/Em = 350/452 nm) were originated from humic-like substances and fluorescence of peak B (Ex/ Em = 275/338 nm) was attributed to protein-like substances. Fluorescence of peaks A, B, and C could be quenched by Cu(II). The effective quenching constants (lg K_a) were 2.8?C5.84 for peak A, 6.4?C9.24 for peak B, and 3.48?C6.68 for peak C, respectively. The values of lg K_a showed a decreasing trend with increasing temperature, indicating that the quenching processes were static in nature. The binding constants (lg K_b) followed the order of peak A>peak B>peak C, implying that the humic-like substances in EPS have greater Cu(II) binding capacity than the protein-like substances. The binding site number, n, in EPS-Cu(II) complexes for peaks A, B, and C was less than 1. This suggests the negative cooperativity between multiple binding sites and the presence of more than one Cu binding site.     

固相微萃取在大气样品分析中的应用

固相微萃取技术(SPME)是一种集萃取、分离、浓缩、进样于一体的新型样品采集及前处理技术.本文综述了SPME法测定大气中挥发性有机物的研究进展,详细阐述了SPME法对气态样品测定装置的实现和工作条件的选择,包括萃取纤维涂层、萃取时间、萃取温度、萃取湿度以及解吸温度及时间等;同时例举了SPME法在气态有机物定量测定中的应用实例.本文可为SPME法测定气态样品的分析提供参考.     

膨润土基共聚复合物的制备及对亚甲基蓝的脱色性能

将乙酸乙烯酯、马来酸酐和丙烯酸作为功能性单体,在钠基膨润土分散体系中进行原位共聚反应,制备了一种膨润土基共聚复合物(P(MAVM)/NaB),采用FT-IR、XRD、SEM等手段对其结构进行了表征.结果表明,NaB与共聚物均匀复合,其中部分高分子链进入了膨润土层间,扩大了缝隙.将膨润土基共聚复合物用于染料亚甲基蓝(MB)的吸附,考察了影响膨润土基共聚复合物吸附亚甲基蓝的主要因素.结果表明:25℃,吸附剂用量为0.1 g.L-1,振荡5 min,MB初始浓度为20 mg.L-1的条件下,MB脱色率可达97.7%,吸附容量达195.46 mg.g-1.处理后水样的色度达到国家污水综合排放一级标准.同时研究了吸附机理,结果发现:吸附过程符合准二级动力学模型,MB通过电中和、氢键及范德华力作用被P(MAVM)/NaB吸附.