层间组装TiO2蒙脱土的制备及其用于汽油脱硫过程的研究

采用溶胶凝胶法制备了TiO2柱撑蒙脱土,并将样品用于FCC汽油的脱硫。利用XRD、SEM、N2吸附/脱附和FTIR分析技术对制备样品进行表征。考察了钛酸丁酯与NaMMT的比例以及焙烧温度对样品结构和脱硫性能的影响。TiO2柱撑蒙脱土的比表面积为100～215 m2/g,平均孔径为40～70 nm,总孔容为015～022 cm3/g。硫容量达到165 mg/g,是400 ℃焙烧原土硫容量的2倍。     

芳胺抗爆剂对100号无铅航空汽油性质的影响

研究了马达法辛烷值（MON）不低于95的无铅航空汽油的配制方法,考察了加入苯胺、N-甲基苯胺、间甲苯胺后,所调制汽油的MON、冰点、馏程等重要性质受到的影响。航空汽油的MON随芳胺添加量增加而提高,且不同芳胺对MON的影响程度不同。向基础油中添加体积分数为5%的苯胺、间甲苯胺或7%的N-甲基苯胺时,MON均可达99.5以上,而加入芳胺会同时提高航空汽油的冰点、90%馏出温度和终馏点,使汽油难以达到质量指标。用沸点较低的苯胺和熔点较低的N-甲基苯胺复配的方法,添加后所调制航空汽油的MON、冰点和馏程均可满足国标要求。     

钙改性NiO/ZnO-Al2O3-SiO2吸附剂成型后的 反应吸附脱硫性能

采用浸渍沉淀法制备钙改性NiO/ZnO-Al₂O₃-SiO₂粉末吸附剂,通过压片成型方式制备成型吸附剂。比表面积及孔径分布（BET）、扫描电子显微镜（SEM）和X射线衍射（XRD）表征结果表明,成型吸附剂ZnO和NiO晶体分布均匀,比表面积147.51 m²/g,孔容0.28 cm³/g,平均孔径6.38 nm。在420℃、氢气压力2.9 MPa、氢油体积比52.5、质量空速9.76 h^-1的反应条件下,成型吸附剂的穿透硫容可达46.51 mg/g,经过5个周期循环再生后脱硫性能保持优良。此外,吸附剂还具有一定的脱氮性能。反应后吸附剂的X射线能量色散谱（EDS）表征结果表明氧质量分数降低,硫质量分数增加;ZnO的XRD特征峰变弱,出现了明显的ZnS特征峰;X射线光电子能谱（XPS）结果表明吸附剂在结合能为852.78 eV处分裂出一个对应于NiS_x的特征谱,说明吸附脱硫过程有NiS_x的生成。     

鞋用胶粘剂“三苯”来源分析

目的:为了解未使用"三苯"作为鞋用胶粘剂溶剂时制鞋车间检测到"三苯"的来源。方法:抽取本地现有5家鞋用胶粘剂厂家的20份产品和40份原材料,依据GB 19340-2003、GB 18583-2001检测评价。结果:检测出"三苯"的胶粘剂占80%(16/20);原材料溶剂汽油检测出"三苯"占80%(8/10),二氯乙烷、丙酮、醋酸乙酯各10份未检测出"三苯"。结论:把好原材料进货关,在鞋用胶粘剂生产的督查中加强原材料的检查。     

The global experience with lead in gasoline and the lessons we should apply to the use of MMT

As leaded gasoline is on the verge of being eliminated from all gasoline worldwide another neurotoxin has been put on the market as a lead substitute. Initial concerns regarding the potential adverse health impacts of this additive have emerged and some evidence indicates that its use could damage pollution controls on advance gasoline fueled vehicles. This paper attempts to draw upon the experience with lead in gasoline to see what lessons we should have learned and how these lessons should apply to the use of the new additive, methylcyclopentadienyl manganese tricarbonyl (MMT). Based on the global experience with lead, the question is whether we have sufficient information to conclude that the precautionary principle should apply to the use of MMT; this would require the developer of the additive to demonstrate conclusively that it is safe before it is sold around the world.     

The efficacy of chelation therapy and factors influencing mortality in lead intoxicated petrol sniffers

Backgmund: The use of chelating agents to treat patients with petrol sniffing encephalopathy has been controversial, since alkyllead additives in petrol are not chelatable. A high mortality has also been reported in hospitalised petrol sniffers.
Aims : (i) Evaluate the efficacy of chelating agents in mobilising lead for excretion and lowering blood lead; (ii) Review factors contributing to mortality in hospitalised petrol sniffers.
Methods : All males chelated between 1992–1993 were studied (n = 20). Blood and urinary lead were measured daily before and during chelation then twice weekly until discharge. Parenteral calcium disodium edetate (EDTA) and dimercaprol (BAL) were administered together, every six hours for five days, seven patients subsequently received oral D-penicillamine until discharge. Clinical details were reviewed for eight patients with petrol sniffing encephalopathy who died between 1990–1994.
Results : Urinary lead excretion substantially increased during parenteral chelation (median excretion=I13 μM/L days, compared with pre-chelation excretion =1.1 μM/day). Median blood lead concentration fell from 4.83 μM/L (pre-chelation) to 1.91 μM/L (post-chelation). D-Penicillamine did not appear to increase urinary lead excretion appreciably. All eight deaths followed sepsis; five from complications of aspiration pneumonia.
Conclusions : Airway maintenance and management are crucial for survival in these patients. In the short-term, parenteral chelation was effective in mobilising lead for excretion and reducing blood lead in encephalopathic petrol sniffers and was comparable to cases of inorganic lead intoxication. However, as in the treatment of inorganic lead intoxication, the long-term efficacy of chelation for petrol sniffers remains controversial. Prevention strategies against petrol sniffing at a community level are recommended.     

Fresh gasoline emissions, not paved road dust, alter cardiac repolarization in ApoE−/− mice

Fresh vehicular emissions potentially represent a ubiquitous environmental concern for cardiovascular health. We compared electrocardiographic effects of fresh gasoline engine emissions with resuspended paved road dust in a mouse model of coronary insufficiency. Apolipoprotein E (ApoE)^−/− mice on a high fat diet were exposed by whole-body inhalation to either gasoline emissions at 60 μg/m³ particulate matter (PM), an equivalent atmosphere with particles filtered out of the whole exhaust, or paved road dust at 0.5 and 3.5 mg/m³ for 6 h/d for 3 d. Radiotelemetry recordings of electrocardiogram (ECG) were analyzed for changes in T-wave morphology (QT interval, T-wave amplitude, and T-wave Area). Following exposures, lung lavage and blood samples were obtained to assay for markers of pulmonary and systemic inflammation. No exposure induced significant changes in heart rate and only the high concentration of road dust induced signs of pulmonary inflammation. T-wave area exhibited significant deviation from baseline values during exposure to gasoline exhaust particulates, but not to either concentration of road dust or gasoline emissions sans particulates. Gasoline-exposed mice demonstrated elevated plasma endothelin-1, but did not cause systemic inflammation. These data support the hypothesis that freshly-generated engine emissions, as opposed to resuspended paved road dust, may drive cardiac effects that have been observed at road-sides in the environment. The absence of ECG effects for both very high concentrations of road dust PM and equivalent concentrations of the vapor/gas phase of gasoline engine exhaust further indicate the specific risk conferred by fresh vehicular PM.     

Risk of esophageal, ovarian, testicular, kidney and bladder cancers and leukemia among finnish workers exposed to diesel or gasoline engine exhaust

Occupational exposure to diesel exhaust has been classified as probably carcinogenic and that to gasoline engine exhaust as possibly carcinogenic to humans. Earlier results concerning cancers other than lung cancer are scarce and inconsistent, and exposure-response relations have seldom been reported. We followed up a cohort of all economically active Finns born between 1906 and 1945 for 30 million person-years during 1971-1995. Incident cases of esophageal cancer (n = 2,198), ovarian cancer (5,082), testicular cancer (387), kidney cancer (7,366), bladder cancer (8,110) and leukemia (4,562) were identified through a record linkage with the Finnish Cancer Registry. Occupations from the population census in 1970 were converted to exposures to diesel and gasoline engine exhausts with a job-exposure matrix (FINJEM). Cumulative exposure (CE) was calculated as product of prevalence, level and estimated duration of exposure. The relative risk (RR) of cancer for exposure categories in relation to the unexposed group was calculated using the Poisson regression model and adjusted for confounders. An increasing RR for ovarian cancer was observed with the increasing CE of diesel exhaust (p for trend = 0.006). The RR in the highest CE category was 3.69 (95% CI = 1.38-9.86). For gasoline engine exhaust, the RR was significantly increased only in the middle CE category (1.70; 95% CI = 1.11-2.62). Slight elevations of RR for bladder and kidney cancers were found at the lowest exposure level of engine exhausts, largely attributable to drivers. No effect of the exposures was observed for the other cancers. This study suggests an exposure-response relation between diesel exhaust and ovarian cancer.     

顶空进样毛细管气相色谱法测定蚕蛹提取物中汽油的残留量

目的 建立测定蚕蛹提取物中汽油残留量的方法.方法 采用顶空进样毛细管气相色谱法测定,色谱柱为HP-1毛细管柱;程序升温, 初始40 ℃,保持10 min,每分钟10 ℃升至150 ℃,保持8 min.结果 在确定的色谱条件下各组分能基线分离,线性关系良好;加样回收率为102.6%.最低检测限为26.3 ng·mL-1.结论 该方法灵敏度和准确度均达到有机溶剂残留量检测的要求,可用于蚕蛹提取物中汽油残留量的测定.     

Comparison of mutagenicity and calf thymus DNA adducts formed by the particulate and semivolatile fractions of vehicle exhausts

In this study we compared the ability of extractable organic material from particulate and semivolatile fractions of gasoline emission to induce mutations in bacteria and form adducts with calf thymus (CT) DNA with corresponding data obtained from diesel exhaust. Exhaust particles from gasoline-powered passenger cars were collected on filters and semivolatile compounds were collected on polyurethane foam (PUF). The mutagenicity of the soluble organic fraction (SOF) was determined in Salmonella typhimurium strain TA98 and the DNA binding of aromatic compounds in the extracts was assessed by in vitro incubations with CT DNA and rat liver S9 (oxidative activation) or xanthine oxidase (reductive activation) followed by butanol-enhanced (32)P-postlabeling analysis. Semivolatile fractions of gasoline emission collected on PUF formed more CT DNA adducts than filter extracts under all reaction conditions, but showed a lower mutagenic potential than the corresponding particulate samples. This suggests that the capacity of PUF to collect exhaust particle-derived compounds and/or the efficiency of xanthine oxidase and enzymes in the rat liver S9 to activate these compounds to DNA binding metabolites was higher than expected. Gasoline extracts, benzo[a]pyrene and diesel particulate matter (SRM 1650) formed more S9-mediated DNA adducts as their dose increased, although a linear dose-response was not observed for the gasoline exhausts. Lower concentrations of gasoline and diesel extracts bound to DNA with greater efficiency than did 8-fold higher doses, suggesting complex interactions and/or an inhibition of S9 enzyme activities by the high doses. Diesel extracts formed higher levels of adducts than gasoline extracts, especially with the reductive activation system, suggesting that diesel extracts contain high levels of nitro-polycyclic aromatic hydrocarbons (nitro-PAHs). The higher direct-acting Salmonella mutagenicity in diesel extracts in comparison with gasoline extracts is consistent with diesel extracts containing higher concentrations of nitro-PAHs. The results of this study indicate that diesel extracts are more mutagenic and form more DNA adducts than gasoline extracts and that the effects of extract dose on DNA adduct formation are complex.