鄱阳湖平原浅层地下水有机污染物含量特征与健康风险评价

为掌握鄱阳湖平原地下水的有机物污染状况,采样并分析了该区地下水中14种挥发性有机物(VOCs)与10种半挥发性有机物(SVOCs)的含量,利用美国环境保护署(USEPA)的健康风险评价模型对其进行健康风险评价。结果表明:鄱阳湖平原地下水的这些有机物的检出率为3. 03%～27. 27%,其中14种VOCs的检出率为6. 06%～15. 15%,10种SVOCs的检出率为3. 03%～27. 27%,部分区域地下水受有机物污染,主要污染物为1,1,2-三氯乙烷、苯并(a)芘和萘;使用内梅罗多项指标的综合污染指数评价污染程度,区域有机物污染特征分为无污染、轻度污染、中度污染以及严重污染四个等级,污染源主要来自杀虫剂、石油化工企业和垃圾填埋场;有机的致癌物质通过饮用途径产生的健康风险远大于非致癌物质的健康风险,其中三氯乙烯、1,1-二氯乙烷、1,2-二氯乙烷、1,1,2,2-四氯乙烷、1,2-二氯丙烷、1,1,2-三氯乙烷、苯并[a]芘等通过饮水产生的致癌风险水平分别为最小可接受水平10-6的7. 06、1. 06、18. 7、54、1. 64、14. 4、2. 87倍,a-六六六通过饮水途径引起的致癌风险水平甚至高达1. 03×10~(-4),是区域地下水中主要致癌风险物质。研究成果可为鄱阳湖平原地下水水质污染状况研究及治理监管工作提供理论依据,为其他区域地下水有机物的监测和质量控制提供参考和借鉴。     

Hydrophobic organic chemicals in urban fog

The concentrations and aqueous/particle distributions of three classes of hydrophobic organic chemicals, n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were measured during the autumn of 1986's fog events in the urban area of Zürich, Switzerland. Concentrations of the chemicals in fog were in the range of 10–110 ng ml⁻¹ for n-alkanes (C₁₉–C₃₅), 6–60 ng ml⁻¹ for PAHs (21 compounds) and 7–22 ng ml⁻¹ for PCBs (31 congeners). In many samples, the concentration of individual n-alkanes and PAHs exceeded their water solubility, probably due to their association with dissolved and/or colloidal organic matter. All of the PAHs, except for phenanthrene, were measured as part of the particulate phase. Both the n-alkanes and PCBs showed a trend of increasing particle association with increasing hydrophobicity, but the trends were distinctly different. The presence of PCBs, PAHs, and n-alkanes at these concentrations suggest that fog is an excellent scavenger of hydrophobic organic chemicals. For a forested area near Zürich, Switzerland, it was estimated that the deposition of n-alkanes and PAHs by fog may be about equal to deposition via rain, but that fog may be 100 times more important than rain for the deposition of PCBs.     

铜铈复合氧化物上石化行业典型VOCs的氧化行为与动力学

采用共沉淀法和等体积浸渍法制备了CuCeO x复合催化剂,对材料的物化性质进行了XRD、低温N2吸脱附、H2-TPR和O2-TPD表征.以石化行业典型VOCs(苯、甲苯和正己烷)为探针污染物,研究了污染物组成与浓度、反应空速、O2浓度、H2O浓度和催化剂种类对其氧化行为的影响,并对反应动力学参数进行了模型拟合.共沉淀得到的催化剂具有均匀的活性相、好的低温可还原性能和较多的活性表面氧物种.甲苯氧化率随着污染物浓度升高而降低,高转化率下苯浓度与其氧化率无相关性,正己烷的氧化率与入口浓度呈正比.苯能够显著抑制甲苯的氧化,而甲苯加入有利于苯的氧化.正己烷对苯氧化的影响较小,但能够促进甲苯的转化,苯系物对正己烷氧化有明显的抑制作用.低空速和高氧浓度都有利于污染物的氧化,氧浓度的变化对正己烷和苯的氧化影响较小.水汽对甲苯的氧化有明显的抑制作用,而对苯和正己烷氧化有明显的促进作用.共沉淀催化剂具有更好的甲苯和苯氧化性能,而无水条件下浸渍催化剂具有更好的正己烷氧化性能.拟一级动力学模型能够很好地模拟不同条件下污染物的氧化行为.     

挥发性氯代烃在湿润土壤中的平衡吸附研究

吸附是挥发性氯代烃(volatile chlorinated hydrocarbons,VCHs)赋存于土壤的主要机制之一.开展动态吸附实验,研究了4种常见VCHs污染物在我国8种典型土壤中的吸附平衡关系.结果表明,土壤在干燥条件下对VCHs气体的吸附能力要远大于湿润条件,且随含水率的升高吸附能力急剧下降,在含水率达到10%以后土壤吸附量趋于稳定.湿润土壤对三氯乙烯(TCE)、四氯乙烯(PCE)、1,1,1-三氯乙烷(MC)气体的吸附等温线符合Henry型吸附等温式,而1,1,2-三氯乙烷(1,1,2-TCA)符合Freundlich模型.VCHs在湿润土壤中的吸附量总体上与土壤有机碳(soil organic carbon,SOC)含量呈正相关,且受SOC类型和化合物极性影响较大.弱极性的TCE、PCE在土壤中的吸附能力与SOC含量呈严格正相关,而极性的MC、1,1,2-TCA在黑土等高碳土壤中不仅与SOC含量有关,还受到SOC物质组成的影响.建立了TCE和PCE在湿润土壤中的平衡吸附量预测模型,预测值与实测值相关性良好(n=80,R2=0.98).     

珠江三角洲机动车挥发性有机物排放化学成分谱研究

根据珠三角地区机动车挥发性有机物排放(VOCs)贡献特征,选取在用轻型汽油车、轻型柴油车、液化石油气(LPG)出租车和摩托车,采用底盘测功机及实际道路测试,获取了以上车型尾气排放的VOCs化学成分(59种非甲烷碳氢化合物)特征谱.轻型汽油车以及摩托车的尾气组成中芳香烃含量最高,其次为烷烃;苯系物、异戊烷以及乙烯占轻型汽油车尾气VOCs组成的54.5%;苯系物、异戊烷以及乙炔占摩托车尾气组成的54.6%.轻型柴油车的尾气组成中烷烃比例最高,其次是芳香烃和烯炔烃.除了苯和甲苯,正十一烷、正十二烷、正癸烷、乙烯、丙烯、1-丁烯亦在柴油车尾气中占有重要比例(41.2%).LPG出租车尾气组成以丙烷、正丁烷、异丁烷为主,并伴有较高比例的1,2,4-三甲基苯、1,2,3-三甲基苯和甲苯.与类似研究比较结果表明:由于在油品、排放标准及采样与分析方法等方面的差异,机动车排放源成分谱相关研究结果仍存在一定的差异性,建议对机动车成分谱研究在尾气采样与分析方法等方面进行规范化和标准化.     

Modeling the influence of ethanol on the adsorption and desorption of selected BTEX compounds on bentonite and kaolin

The study investigated the effects of ethanol on the adsorption properties of bentonite and kaolin for benzene and toluene removal.     

Detection and Molecular Characterization of Human Noroviruses in Korean Groundwater Between 2008 and 2010

RT-PCR, nucleotide sequencing, and phylogenetic analysis were performed for genotyping and molecular characterization of noroviruses isolated from Korean groundwater. Among 160 samples collected from 80 sites between 2008 and 2010, 14 samples (8.7?%) from 12 sites were positive for noroviruses (NoVs). The percentages of NoV-positive samples in 2008, 2009, and 2010 were 22.2, 3.2, and 0?%, respectively, representing a yearly decrease. GII-positive samples (n?=?9, 5.6?%) outnumbered GI-positive samples (n?=?5, 3.1?%). The genotypes of the GI NoVs were GI.2, GI.5, and GI.6, and the genotypes of the GII NoVs were all GII.4. One sample, HM623465, was very similar to CUK-3 and CBNU2 and two GII.4 sequences isolated from the stool of Korean gastroenteritis patients. A BLASTN search revealed several nucleotide sequences highly similar to those of NoVs isolated in this study. The original isolation sources for these similar NoVs were mostly stool (n?=?731, 80.0?%) and groundwater (n?=?135, 14.8?%), and all the countries from which they were isolated were almost in Asia (96.0?%); specifically, China (n?=?192, 21.0?%), Japan (n?=?383, 41.9?%), Korea (n?=?296, 32.4?%), and other Asian countries (n?=?6, 0.7?%). These results suggest that Korean groundwater might be contaminated with NoVs from the stool of infected patients and that these NoVs in turn cause new cases of gastroenteritis through a typical fecal-oral route with region-specific circulation. Therefore, it is important to properly treat sewage, which may include waterborne viruses and manage point sources in groundwater for national health and sanitation. In addition, continuous molecular surveillance remains important for understanding circulating NoVs.     

麦草及其烟尘中正构烷烃的组成

在明火和闷烧条件下对6种麦草进行焚烧试验,用GC/MS测定了秸秆和烟尘中正构烷烃的组成.结果表明,从麦秆和烟尘中检出的正构烷烃主要是C16~C33.麦秸中正构烷烃的总含量变化范围是19.6~62.3 mg·kg-1,平均值为36.0mg·kg-1.低碳数(碳数相似文献   

孔径调变对MCM-41分子筛吸附VOCs性能的影响

采用3种不同碳链长度的季铵盐表面活性剂C_nTAB(n=8,12,16)为模板剂,分别合成8-MCM-41、12-MCM-41和16-MCM-41介孔分子筛,并以甲苯、邻二甲苯、均三甲苯为吸附对象,考察了介孔分子筛动态吸附VOCs的性能.结果表明,通过减少表面活性剂的碳链长度,可以成功地把MCM-41分子筛的孔径调变为4.1、3.2和2.4 nm.吸附实验结果表明,当MCM-41孔径减小时,其对低浓度甲苯、邻二甲苯的吸附量大幅上升,均三甲苯存在孔道扩散效应,其吸附量增加不明显.吸附等温线表明,在2.4 nm孔道内,3种芳烃分子均属于典型的Langmuir单分子层吸附;当孔径大于2.4 nm时,芳烃分子出现明显的多层吸附和毛细凝聚现象.     

Occurrence and fate of chlorinated methylsiloxanes in surrounding aqueous systems of Shengli oilfield, China

Mono-chlorinated products of cyclic volatile methylsiloxanes (cVMS), i.e., Monochlormet-hylheptamethylcyclotetrasiloxane [D3D(CH₂Cl)], monochlormethylnonamethylcyclopenta-siloxane [D4D(CH₂Cl)], and monochlormethylundemethylcyclohexasiloxane [D5D(CH₂Cl)], were detected in water [<LOQ (Limit of quantitation) -86.3 ng/L, df (detection frequency) = 23%-38%, n=112] and sediment samples [<LOQ-504 ng/g dw (dry weight), df = 33%-38%, n=112] from 16 lakes located in Shengli oilfield of China, and had apparent increasing trends (31%-34% per annum) in sediments during Year 2014-2020. Simulated experiments showed that chloro-cVMS in sediment-water system had approximately 1.7-2.0 times slower elimination rates than parent cVMS. More specifically, compared with those of parent cVMS, volatilization (86-2558 days) and hydrolysis (135-549 days) half-lives of chloro-cVMS were respectively 1.3-2.0 and 1.8-2.1 times longer. In two species of freshwater mussels (n=1050) collected from six lakes, concentrations of chloro-cVMS ranged from 9.8-998 ng/g dw in Anodonta woodiana and 8.4-970 ng/g dw in Corbicula fluminea. Compared with parent cVMS, chloro-cVMS had 1.1-1.5 times larger biota-sediment accumulation factors (2.1-3.0) and 1.1-1.7 times longer half-lives (13-42 days). Their stronger persistence in sediment and bioaccumulation in freshwater mussels suggested that environmental emission, distribution and risks of chloro-cVMS deserve further attention.     

机动车尾气排放VOCs源成分谱及其大气反应活性

选取轻型汽油车、重型柴油车和摩托车等城市典型机动车种分别采用底盘测功机及实际道路实验,结合SUMMA罐采样的方法,获得了小轿车、出租车、公交车、卡车、摩托车和LPG助动车的尾气VOCs样品,利用气相色谱-质谱分析了各车型机动车尾气VOCs的浓度及其物种组成.结果表明,轻型汽油车尾气VOCs以甲苯、二甲苯等芳香烃为主,占43.38%～44.45%;重型柴油车以丙烷、n-十二烷及n-十一烷等烷烃组分为主,占46.86%～48.57%,还有13.28%～15.01%的丙酮等含氧特征组分;摩托车与LPG助动车的主要成分为乙炔,分别占39.75%和76.67%左右.各车型中,摩托车和轻型汽油车尾气VOCs的化学活性显著高于重型柴油车辆,以上海市为例,其大气化学活性贡献分别占55%和44%左右,是影响城市和区域大气氧化能力的关键污染源,其中以甲苯、二甲苯、丙烯、苯乙烯等关键活性物种的贡献最大.     

A preliminary investigation on the use of organic ionic liquids as green solvents for acylation and oxidation reactions

Different organic ionic liquids (OILs) have been used as green solvents in Friedel–Crafts acylation and alcohol oxidation reactions. Specifically, three OILs were employed, 1-ethyl-3-methylimidazolium chloride, tetraethylammonium bromide, and 1-butyl-3-methylimidazolium chloride, and four reactions studied, acylation of toluene by acetyl chloride, acylation of benzene by propionyl chloride, oxidation of benzyl alcohol by N-methylmorpholine N-oxide, and oxidation of salicylic alcohol by o-iodoxybenzoic acid. The reactions were carried out, at room temperature, in a well-stirred lab-scale glass batch reactor, under inert atmosphere and for reaction times ranging from 5 to 90 min. Gas chromatography was employed to characterize the reaction products. First of all, the desired products yield as a function of the reaction time was investigated. Moreover, simple kinetic models were built for the interpretation of the experimental results. Additional tests were carried out to assess the possibility of recycling the OILs employed. The results of this preliminary study were satisfactory as the OILs investigated proved to be good media in which to carry out the reactions studied in this work (desired products yield greater than 90% were achieved). Moreover, the reaction rate expressions of the kinetic models were able to satisfactorily predict the experimental results. Finally, the possibility of recycling the OIL (in one of the reactions) was proved to be feasible and this suggests the use of recycled OIL together with a fresh make-up, to match high yield values with economical/ecological advantages.     

Preparation of MnO2 decorated Co3Fe1Ox powder/monolithic catalyst with improved catalytic activity for toluene oxidation

In this paper, KMnO₄ was used to pre-treat Co₃Fe-layered double hydroxides (LDH) precursor to prepare MnO₂ decorated Co₃Fe₁O_x catalyst. The toluene oxidation performance of the catalyst was investigated systematically. The optimized 0.1MnCF-LDO catalyst exhibited the best catalytic performance, and the temperatures of 50% and 90% toluene conversion (T₅₀ and T₉₀) were 218 and 243°C, respectively. The apparent activation energy (E_a) was 31.6 kJ/mol. The characterization results showed that the pre-redox reaction by KMnO₄ could increase the specific surface area, Co³⁺ species amount and oxygen defect concentration of the catalyst, which are the main reason of the improved toluene catalytic activity. Besides, this method was also applied to enhance toluene oxidation of iron mesh based monolithic catalyst. The 0.1MnCF-LDO/Iron mesh (IM) catalyst showed a 90% toluene conversion at around 316°C which was much lower than that of without MnO₂ addition (359°C). In addition, the water resistant of all the catalysts was studied as well, all the samples showed relatively good water resistance. The toluene conversion still remained to be over >80% even in the presence of 10 vol.% water vapor.     

厦门冬春季大气VOCs的污染特征及臭氧生成潜势

2014年1~4月在厦门市城区和郊区开展冬春季节大气样品的采集,采用大气预浓缩系统与GC/MS联用技术定量了48种大气挥发性有机物(VOCs),对比分析了冬春季城区和郊区大气VOCs的污染特征,并利用最大增量反应活性(MIR)估算了大气VOCs的臭氧生成潜势(OFP).结果表明,冬季厦门城区和郊区大气中VOCs的平均体积分数分别为11.13×10-9和7.17×10-9,春季厦门城区和郊区大气中VOCs的平均体积分数分别为24.88×10-9和11.27×10-9,且均表现为烷烃芳香烃烯烃.通过B/T值探讨城区和郊区VOCs的来源发现,机动车和溶剂挥发是城区VOCs的主要来源,郊区VOCs除了局地源的贡献外,还受到外来污染物扩散传输的影响.城、郊区的主要VOCs包括丙烯、正丁烷、异丁烷、正戊烷、异戊烷、正己烷、苯、甲苯、乙苯和间对二甲苯,这10种组分对两地VOCs的贡献表现为春季(城区和郊区分别为62.83%和53.74%)高于冬季(城区和郊区分别为61.57%和45.83%).城、郊区VOCs的臭氧生成潜势分析显示,芳香烃的相对贡献率最大,其次是烯烃,烷烃最小.C3、C4类烯烃和苯系物是厦门城区和郊区活性较高的物种,对臭氧的贡献较大.比较观测期间城区和郊区VOCs的平均MIR值可知,郊区VOCs的活性高于城区.     

Regulatory effectiveness and the long-run policy horizon: The case of U.S. toxic chemical use

This paper employs state-of-the-art time series analysis to examine the long-run economic and institutional drivers of toxic chemical use behavior in the U.S. Toxic chemicals are classified into growth, Environmental Kuznets Curve (EKC), and kinked-growth chemicals, according to their long-run use trend behavior. Cointegration analysis shows that while some toxic chemicals have been successfully reduced by regulatory efforts, a majority of the toxic chemicals used in commercial products share a long-run equilibrium with national accounts and industrial production, suggesting that toxic chemical use has been largely driven by changes in GDP, industrial production, and private R&D investments, rather than by government regulations. Estimated structural break results indicate that the 1986 Emergency Planning and Community Right-to-Know Act, which created the Toxic Release Inventory has had impact on the consumptive use of more poisonous industrial chemicals than command-and-control regulations.     

印刷电路板(PCB)厂挥发性有机物(VOCs)排放指示物筛选

采用VOCs快速测定仪和SUMMA罐采样、GC/MS分析方法,采样分析了上海某工业区3个印刷电路板厂生产车间和废气排放口的VOCs含量水平、组成特征和源成分谱.结果表明,在9月和12月2次采样期间,A、B、H厂生产车间总挥发性有机物(TVOCs)(9月/12月)最高浓度分别为(2.94/2.01)×10-9、(3.18/1.11)×10-6、(0.70/0.18)×10-9;废气排放口TVOCs最高浓度则分别为(0.86/0.90)×10-9、(31.2/12.0)×10-6、(1.24/0.30)×10-9.GC/MS分析结果表明,主要检出了烷烃、烯烃、苯系物、酮类、氯代烷烃、氯代苯类、酯类等7大类共67种VOCs化合物;A、B、H厂生产车间/废气排放口最高检出物和检出浓度分别为:2-丁酮6.73 mg.m-3/2-甲基己烷5.93 mg.m-3、乙酸乙酯8.90 mg.m-3/丙烷9.64 mg.m-3、丙烷2.04 mg.m-3/丙烷1.69 mg.m-3.苯、甲苯、二甲苯检出率均为100%,三厂各点位最高检出浓度/平均浓度分别为0.077 mg.m-3/0.035 mg.m-3、0.56 mg.m-3/0.31 mg.m-3、0.21 mg.m-3/0.12 mg.m-3(间+对-二甲苯)和0.081 mg.m-3/0.050 mg.m-3(邻-二甲苯).源成分谱和PCA分析结果表明,A、B厂的VOCs特征轮廓图谱较相似,特征化合物为苯、甲苯、二甲苯以及丙酮和2-丁酮;H厂主要特征污染物除三苯外,还有氯苯和氯代烷烃类化合物.结合原辅材料及生产工艺分析,溶剂、涂料使用和工艺过程的逸散是生产车间面源VOCs排放的主要来源,废气排放口是VOCs重点排放点源.     

Physiological cellular responses and adaptations of Rhodococcus erythropolis IBBPo1 to toxic organic solvents

A new Gram-positive bacterium, Rhodococcus erythropolis IBBPo1（KF059972.1） was isolated from a crude oil-contaminated soil sample by enrichment culture method. R. erythropolis IBBPo1 was able to tolerate a wide range of toxic compounds, such as antibiotics（800–1000 μg/mL）,synthetic surfactants（50–200 μg/mL）, and organic solvents（40%–100%）. R. erythropolis IBBPo1 showed good tolerance to both alkanes（cyclohexane, n-hexane, n-decane） and aromatics（toluene, styrene, ethylbenzene） with logPOW（logarithm of the partition coefficient of the solvent in octanol–water mixture） values between 2.64 and 5.98. However, alkanes were less toxic for R. erythropolis IBBPo1 cells, compared with aromatics. The high organic solvent tolerance of R. erythropolis IBBPo1 could be due to the presence in their large genome of some catabolic（alkB, alkB1, todC1, todM, xylM）, transporter（HAE1） and trehalose-6-phosphate synthase（otsA1, KF059973.1） genes. Numerous and complex physiological cellular responses and adaptations involved in organic solvent tolerance were revealed in R. erythropolis IBBPo1 cells exposed 1 and 24 hr to 1% organic solvents. R. erythropolis IBBPo1 cells adapt to 1% organic solvents by changing surface hydrophobicity, morphology and their metabolic fingerprinting.Considerable modifications in otsA1 gene sequence were also observed in cells exposed to organic solvents（except ethylbenzene）.     

Photochemical aerosol formation from aromatic hydrocarbons in the presence of NOx

By using a 4-m³ chamber, photochemical aerosol formation from mixtures of aromatic hydrocarbons (AHCs) and nitrogen oxides (NO_x) was studied with the main purpose of determining the aerosol yield. Altogether, 18 aromatic species were investigated, including toluene, xyluene, xylenes, ethylbenzene and methoxybenzene. Evolution of the aerosol was monitored through the measurement of the total number ([CN]) and volume (V) concentrations. Aerosol-forming potential of different aromatics was examined in terms of the maximum growth rates of [CN] and V. By putting dry sheath air into an electrical aerosol analyzer, the net organic volume concentration (V_d) was obtained; then a relation was established between V_d and the C mass concentration, and was used to determine the aerosol yield as defined by the ratio of the particulate C mass to the C mass of the reacted HC. It was found that the yields were larger for toluene, ethylbenzene, and o- and m-ethyltoluene (3.0, 3.1, 3.3 and 3.7%, respectively) but smaller for para-substituted toluene derivatives (< 1.5%).     

Aerosol formation and growth in atmospheric organic/NOχ systems—I. Outdoor smog chamber studies of C7- and C8-hydrocarbons

Outdoor smog chamber experiments have been performed to determine the aerosol-forming potential of selected C₇- and C₈-hydrocarbons in sunlight-irradiated hydrocarbon-NO_χ mixtures. Measured aerosol size distributions were used to determine the rates of gas-to-particle conversion and to study the effects of the addition of SO₂ and/or NH₃ on aerosol formation and growth. The average aerosol yields by mass for the hydrocarbons studied were (the range of measured values for methylcyclohexane and 1-octene are in parentheses):

• •methylcyclohexane 9.2% (0.12–18.8);
• •1-octene 4.2% (0.17–6.9);
• •toluene 18.6%;
• •n-octane <0.001%.

The average yields are accompanied by large standard deviations (see Table 3) and depended strongly on the conditions, particularly the hydrocarbon to NO_χ initial concentration ratio. Addition of SO₂ to the organic/NO_χ systems led to an early nucleation burst and subsequent rapid growth of the newly formed aerosol. In the presence of NH₃, the gas-to-particle conversion rate of the organic/NO_χ system was enhanced perhaps due to the formation of NH₄NO₃ or the reaction of NH₃ with carboxylic acids. Sustained particle formation was observed when both SO₂ and NH₃ were present, presumably as a result of (NH₄)₂SO₄ formation. We have estimated the complexity of the 1-octene aerosol and identified 5-propyl furanone as a component of the aerosol.     

膜生物反应器处理甲苯性能及机制

采用膜生物反应器处理甲苯有机废气,研究了进气浓度、停留时间、循环液喷淋密度和pH值对甲苯去除率的影响.膜生物反应器能高效净化挥发性有机废气,甲苯去除率可达99%.适宜运行条件为:pH值为7.2、停留时间为6.4 s、循环液喷淋密度为2.5 m3.(m2.h)-1.采用GC-MS分析出口气样,研究结果表明乙醛酸(C2H2O3)和乙烯基甲酸(C3H4O2)为甲苯生物降解的中间产物.膜生物反应器处理甲苯机制为甲苯气体通过中空纤维膜传质到生物膜,被生物降解为乙醛酸和乙烯基甲酸,然后继续好氧降解为最终产物二氧化碳和水.