北京及近中国海春季沙尘气溶胶浓度变化规律的研究

对北京和近中国海气溶胶观测资料的统计分析表明，沙尘气溶胶浓度呈现显的年示变化，该变化与沙尘源区及主要输送通道上的气象条件密切相关。运用多元线性回归分析结合气溶胶观测资料和气象资料计算了北京春季沙尘气溶胶家度。结果表明１９７１－１９９５年北京春季沙尘气溶胶浓度总体呈递砬趋势，但进入九十年代，这种递减趋势有所减缓。     

严惩环境污染犯罪观念之反思

目前,中国重大环境污染事故频发,严重危害了公民居住的环境甚至是公共安全,在社会上引起了广泛影响,民众要求严惩环境污染犯罪的观念也日益盛行。从客观上来讲,严惩环境污染犯罪有一定的意义,但此种观念的蔓延也可能带来一系列的副作用,因此有必要对此种观念进行深刻反思。通过对环境污染犯罪进行综合分析可以发现,导致此类犯罪的原因是多方面的,因而预防该类犯罪的方法也应当是多元的,仅仅严惩是起不到防治环境污染犯罪效果的。     

依据GB/T 23466-2009《护听器的选择指南》指导护听器选型

本文介绍了国家标准GB/T 23466-2009《护听器的选择指南》的实施背景及具体内容,对标准使用中噪声环境声压级测量及护听器选择原则中需要关注的事项进行了说明。     

废水中聚丙烯酰胺在H-Beta分子筛上的吸附特性

将H-Beta用于处理含聚丙烯酰胺(PAM)的驱油废水,研究了PAM在H-Beta上的吸附动力学和热力学特征,并考察了吸附条件对吸附效果的影响.结果表明,吸附过程遵循准二级动力学模型;在低PAM初始浓度(100 mg·L-1)时,吸附表观活化能40 k J·mol-1,说明H-Beta对PAM的吸附以化学吸附为主;在高PAM初始浓度(200和500 mg·L-1)时,吸附活化能降低,吸附向物理吸附转变.吸附等温线在低平衡浓度区符合Langmuir模型,25、40和50℃时的单层饱和吸附量分别达到70.2、76.9和90.9 mg·g-1;在高平衡浓度区符合Freundlich模型,表现为多层吸附.吸附主要来自氢键作用,为自发的吸热过程.p H为2~4,吸附剂用量为5 g·L-1时,具有更优的吸附效果.真实废水中油和盐类的存在对PAM在H-Beta上的吸附未产生不利影响.     

源解析中环境受体数据处理与扩展方法的建立

本文对包含污染源或气象条件等发生剧烈变化且数据量小的实测受体数据进行了正态扩展,得到扩展数据.同时,利用PMF和PCA模型验证了扩展方法得到的数据量是否能满足模型的要求.结果表明,扩展范围和扩展受体成分谱个数是两个影响扩展数据合理性的主要因素,最佳扩展条件为:扩展范围取标准差的0.5倍,扩展受体成分谱个数为6个.通过53 h算法标记出每个化学成分时间序列中能够代表污染源或气象条件等发生剧烈变化的值并给出对应的估计值.将与估计值的相对误差(RE)超过80%的被标记的值剔除,其余的替换成估计值,发现扩展后PCA解析结果与原始数据处理后数据解析结果基本一致,能够得到主要贡献的污染源及贡献率;若将被标记的值全部剔除后,则不适合做PCA解析;仅通过PMF验证,且扩展数据与原始数据的解析结果中污染源类的判断一致.将受体数据各化学成分的时间序列中代表污染源或气象条件等发生剧烈变化的值替换成53 h算法给出的估计值,对于受体数据量小且用无源成分谱的多元统计方法解析无法给出结果的情况下的源解析有更大价值.     

加油站埋地油罐人孔井油气爆炸事故模拟实验

根据加油站实际工况,模拟埋地油罐人孔井内发生汽油泄漏时,挥发的油气在人孔井内积聚并遇到点火源发生爆炸的事故.埋地油罐内布置压力传感器,实验人孔井内布置压力传感器,人孔井周围布置热流传感器,以获得事故对埋地油罐、人孔井口人员及设备的影响数据.实验结果表明:爆炸在人孔井内产生的压力冲击波和热辐射冲击,会对人孔井口的人员造成严重伤害,但对埋地油罐罐内不会造成影响.油气闪爆后,人孔井盖可能处于关闭或打开两种状态,使得人孔井内火焰熄灭或形成稳定燃烧,燃烧限制于人孔井,对埋地油罐和周围设施影响较小.     

Abatement of SO2-NOx binary gas mixtures using a ferruginous active absorbent: Part I. Synergistic effects and mechanism

A novel ferruginous active absorbent, prepared by fly ash, industrial lime and the additive Fe(VI), was introduced for synchronous abatement of binary mixtures of SO2–NOx from simulated coal-fired flue gas. The synergistic action of various factors on the absorption of SO2 and NOx was investigated. The results show that a strong synergistic effect exists between Fe(VI) dose and reaction temperature for the desulfurization. It was observed that in the denitration process, the synergy of Fe(VI) dose and Ca/(S + N) had the most significant impact on the removal of NO, followed by the synergy of Fe(VI) and reaction temperature, and then the synergy of reaction temperature and flue gas humidity. A scanning electron microscope(SEM) and an accessory X-ray energy spectrometer(EDS)were used to observe the surface characteristics of the raw and spent absorbent as well as fly ash. A reaction mechanism was proposed based on chemical analysis of sulfur and nitrogen species concentrations in the spent absorbent. The Gibbs free energy, equilibrium constants and partial pressures of the SO2–NOx binary system were determined by thermodynamics.     

自动消解仪-ICP法测定土壤中7种重金属离子实验研究

利用自动消解仪对土壤进行前处理,建立了电感耦合等离子体发射光谱法(ICP-OES)同时测定Cu、Zn、Ni、Cr、Sr、V、Co七种重金属元素含量的方法。该方法的相关系数均在3个9以上。测定了国家标准物质GBW07429土壤中的元素,测定值与标准值一致,相对标准偏差1.6%~4.5%,检出限0.000 2~0.005 mg/L。利用建立的方法测定了天津市土壤中的七种重金属元素含量,为土壤中重金属元素含量的测定提供了简单可靠的分析方法。     

某消失模铸造厂污染防治措施要点分析研究

根据某消失模铸造企业依托相邻的炼铁厂合作建厂的实际条件,对采用宝珠砂造型后消失模铸造车间的废气和废水污染产生环节进行了分析,确定主要污染为废气污染。环评根据企业的具体情况,有针对性地对中频炉熔炼、落砂及砂处理、真空浇铸、抛丸清理等各污染环节提出了合理可行的污染防治措施,并在此基础上重点对真空浇注产生的有机废气的几种处理方法进行了分析,确定该厂将有机废气经真空泵直接引入到炼铁厂煤气电站锅炉进行燃烧处理合理可行,并能满足相应的环保要求。     

Heterogeneous Fenton-like degradation of 4-chlorophenol using iron/ordered mesoporous carbon catalyst

Ordered mesoporous carbon supported iron catalysts(Fe/OMC) were prepared by the incipient wetness impregnation method and investigated in Fenton-like degradation of 4-chlorophenol(4CP) in this work. XRD and TEM characterization showed that the iron oxides were well dispersed on the OMC support and grew bigger with the increasing calcination temperature. The catalyst prepared with a lower calcination temperature showed higher decomposition efficiency towards 4CP and H2O2, but more metals were leached. The effect of different operational parameters such as initial pH, H2O2 dosage, and reaction temperature on the catalytic activity was evaluated. The results showed that 96.1% of 4CP and 47.4% of TOC was removed after 270 min at 30°C, initial pH of 3 and 6.6 mmol/L H2O2. 88% of 4CP removal efficiency was retained after three successive runs, indicating Fe/OMC a stable catalyst for Fenton reaction. 4CP was degraded predominately by the attack of hydroxyl radical formed on the catalyst surface and in the bulk solution due to iron leaching. Based on the degradation intermediates detected by high performance liquid chromatography, possible oxidation pathways were proposed during the 4CP degradation.