The toxicity of methyl tert-butyl ether （MTBE） to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high （2.00×10^4 mg/L） to low...The toxicity of methyl tert-butyl ether （MTBE） to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high （2.00×10^4 mg/L） to low （2 mg/L）. The results showed that the toxicity was low when the concentration of MTBE was in the range 1.00× 10^4-2.00× 10^4 mg/L （the greatest inhibition of growth-rate was 70%-71%, occurred during the day 1-5）. Low concentrations （2-500 rag/L） stimulated algal growth up to the greatest effect of 85%-200% when the concentration of MTBE was 50-100 mg/L during day 3-5. The toxicity of MTBE （72-120 h EC50） was 6.65×10^3-9.58×10^3 mg/L for C. ellipsoidea and that is 1.14× 10^4-2.00× 10^4 mg/L for A. floc-aquae. We found that the toxicity and ecological risk of MTBE for the algal community structure were low and the toxicity was influenced by the duration time of the test.展开更多
The contamination of methyl ten-butyl ether （MTBE） in underground waters has become a widely concerned problem all over the world. In this study, a novel dosed culture system with oxygen supplied by H2O2 was introdu...The contamination of methyl ten-butyl ether （MTBE） in underground waters has become a widely concerned problem all over the world. In this study, a novel dosed culture system with oxygen supplied by H2O2 was introduced for MTBE aerobic biodegradation. After 7 d, almost all MTBE was degraded by a pure culture, a member of β-Proteobacteria named as PMI, in a closed system with oxygen supply, while only 40% MTBE was degraded in one without oxygen supply. Dissolved oxygen （DO） levels of the broth in closed systems respectively with and without H2O2 were about 5-6 and 4 mg/L. Higher DO may improve the activity of monooxygemase, which is the key enzyme of metabolic pathway from MTBE to tert-butyl alcohol and finally to CO2, and may result in the increase of the degrading activity of PM1 cell. The purge and trap GC-MS result of the broth in closed systems showed that tea-butyl alcohol, isopronol and acetone were the main intermediate products.展开更多
A method was developed to determine the concentration of methyl tert-butyl ether(MTBE) in gasoline, diesel and heating oil by gas chromatography(GC) with mass spectrometry(GC-MS) or flame ionization detection(FID). Th...A method was developed to determine the concentration of methyl tert-butyl ether(MTBE) in gasoline, diesel and heating oil by gas chromatography(GC) with mass spectrometry(GC-MS) or flame ionization detection(FID). The diluted gasoline was directly injected into the GC, and the complete separation of MTBE from co-eluting hydrocarbons was not required. GC/MS or GC/FID method can be used to analyze MTBE in different concentration range and have good consistency.展开更多
The power and efficiency of gasoline engines is often improved through the use of fuel with high octane ratings.The octane rating of fuel could be further increased with oxygenate additives such as alcohols and ethers...The power and efficiency of gasoline engines is often improved through the use of fuel with high octane ratings.The octane rating of fuel could be further increased with oxygenate additives such as alcohols and ethers,with methyl tert-butyl ether(MTBE)being one of the most common gasoline additives.展开更多
采用原子转移自由基聚合(ATRP)法聚合甲基烯丙基聚氧乙烯醚(HPEG)和丙烯酸甲酯(PMA),生成低分子量梳形结构的低聚物HPEG/PMA.经Fourier红外光谱(FT-IR)和核磁共振氢谱(1 H NMR)对其结构特征基团进行分析,确认合成了目标产物.对HPEG/PMA...采用原子转移自由基聚合(ATRP)法聚合甲基烯丙基聚氧乙烯醚(HPEG)和丙烯酸甲酯(PMA),生成低分子量梳形结构的低聚物HPEG/PMA.经Fourier红外光谱(FT-IR)和核磁共振氢谱(1 H NMR)对其结构特征基团进行分析,确认合成了目标产物.对HPEG/PMA进行凝胶渗透色谱(GPC)测试,结果表明,ATRP法制备的梳形HPEG/PMA分子量为7.7×103,分布系数为1.11,具有优异的可控性.梳形HPEG/PMA经V(乙醇)∶V(水)=1的NaOH溶液水解,得到梳形结构甲基烯丙基聚氧乙烯醚和丙烯酸(HPEG/PAA)低聚物.展开更多
Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective...Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective detector （GC-MSD） after cryogenic pre-concentration.Benzene,toluene,ethylbenzene and xylenes （BTEX） at the platforms and mezzanines inside the stations averaged （10.3±2.1）,（38.7±9.0）,（19.4±10.1） and （30.0±11.1） μg/m 3,respectively;while trichloroethylene （TrCE）,tetrachloroethylene （TeCE） and para-dichlorobenzene （pDCB）,vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of （3.6±1.3）,（1.3±0.5）,（4.1±1.1）,（2.2±1.1） and （1.2±0.3） μg/m 3,respectively.Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor （platforms and mezzanines） than outdoor with average indoor/outdoor （I/O） ratios of 1.1–9.5,whereas no significant indoor/outdoor differences were found except for benzene and TrCE.The highly significant mutual correlations （p0.01） for BTEX between indoor and outdoor and their significant correlation （p0.05） with methyl tert-butyl ether （MTBE）,a marker of traffic-related emission without other indoor and outdoor sources,indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source.TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air,especially in the mezzanines.展开更多
基金supported by the National Natural Science Foundation of China (No. 20476099)
文摘The toxicity of methyl tert-butyl ether （MTBE） to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high （2.00×10^4 mg/L） to low （2 mg/L）. The results showed that the toxicity was low when the concentration of MTBE was in the range 1.00× 10^4-2.00× 10^4 mg/L （the greatest inhibition of growth-rate was 70%-71%, occurred during the day 1-5）. Low concentrations （2-500 rag/L） stimulated algal growth up to the greatest effect of 85%-200% when the concentration of MTBE was 50-100 mg/L during day 3-5. The toxicity of MTBE （72-120 h EC50） was 6.65×10^3-9.58×10^3 mg/L for C. ellipsoidea and that is 1.14× 10^4-2.00× 10^4 mg/L for A. floc-aquae. We found that the toxicity and ecological risk of MTBE for the algal community structure were low and the toxicity was influenced by the duration time of the test.
基金Project supported by the National Natural Science Foundation of China (No. 20476099) Zhejiang Provincial Natural Science Foundation (No. Y504272).
文摘The contamination of methyl ten-butyl ether （MTBE） in underground waters has become a widely concerned problem all over the world. In this study, a novel dosed culture system with oxygen supplied by H2O2 was introduced for MTBE aerobic biodegradation. After 7 d, almost all MTBE was degraded by a pure culture, a member of β-Proteobacteria named as PMI, in a closed system with oxygen supply, while only 40% MTBE was degraded in one without oxygen supply. Dissolved oxygen （DO） levels of the broth in closed systems respectively with and without H2O2 were about 5-6 and 4 mg/L. Higher DO may improve the activity of monooxygemase, which is the key enzyme of metabolic pathway from MTBE to tert-butyl alcohol and finally to CO2, and may result in the increase of the degrading activity of PM1 cell. The purge and trap GC-MS result of the broth in closed systems showed that tea-butyl alcohol, isopronol and acetone were the main intermediate products.
文摘A method was developed to determine the concentration of methyl tert-butyl ether(MTBE) in gasoline, diesel and heating oil by gas chromatography(GC) with mass spectrometry(GC-MS) or flame ionization detection(FID). The diluted gasoline was directly injected into the GC, and the complete separation of MTBE from co-eluting hydrocarbons was not required. GC/MS or GC/FID method can be used to analyze MTBE in different concentration range and have good consistency.
文摘The power and efficiency of gasoline engines is often improved through the use of fuel with high octane ratings.The octane rating of fuel could be further increased with oxygenate additives such as alcohols and ethers,with methyl tert-butyl ether(MTBE)being one of the most common gasoline additives.
文摘采用原子转移自由基聚合(ATRP)法聚合甲基烯丙基聚氧乙烯醚(HPEG)和丙烯酸甲酯(PMA),生成低分子量梳形结构的低聚物HPEG/PMA.经Fourier红外光谱(FT-IR)和核磁共振氢谱(1 H NMR)对其结构特征基团进行分析,确认合成了目标产物.对HPEG/PMA进行凝胶渗透色谱(GPC)测试,结果表明,ATRP法制备的梳形HPEG/PMA分子量为7.7×103,分布系数为1.11,具有优异的可控性.梳形HPEG/PMA经V(乙醇)∶V(水)=1的NaOH溶液水解,得到梳形结构甲基烯丙基聚氧乙烯醚和丙烯酸(HPEG/PAA)低聚物.
基金Key Project of National Natural Science Foundation of China (No.20436040) and the National NaturalScicnce Foundation of China (No.20176044, No.20476084).
基金supported by the National Natural Science Foundation of China (No. 40821003)the Guangdong Natural Science Foundation (No. 7118013)the State Key Laboratory of Organic Geochemistry and the Hong Kong Polytechnic University Joint Student Program
文摘Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective detector （GC-MSD） after cryogenic pre-concentration.Benzene,toluene,ethylbenzene and xylenes （BTEX） at the platforms and mezzanines inside the stations averaged （10.3±2.1）,（38.7±9.0）,（19.4±10.1） and （30.0±11.1） μg/m 3,respectively;while trichloroethylene （TrCE）,tetrachloroethylene （TeCE） and para-dichlorobenzene （pDCB）,vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of （3.6±1.3）,（1.3±0.5）,（4.1±1.1）,（2.2±1.1） and （1.2±0.3） μg/m 3,respectively.Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor （platforms and mezzanines） than outdoor with average indoor/outdoor （I/O） ratios of 1.1–9.5,whereas no significant indoor/outdoor differences were found except for benzene and TrCE.The highly significant mutual correlations （p0.01） for BTEX between indoor and outdoor and their significant correlation （p0.05） with methyl tert-butyl ether （MTBE）,a marker of traffic-related emission without other indoor and outdoor sources,indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source.TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air,especially in the mezzanines.
