排序方式: 共有5条查询结果,搜索用时 0 毫秒
1
1.
2.
运用分子轨道理论考察甲酚的生物降解特性 总被引:1,自引:0,他引:1
运用分子轨道理论考察了甲酚同分异构体的生物降解特性。计算出最高占据轨道(HOMO)能量的大小,反映了甲酚同分异构体生物降解反应的难易程度,且结论与事实相符合。 相似文献
3.
4.
A method for sampling and analysis of phenolic compounds in workplace atmospheres using Amberlite XAD‐2 sorbent tubes has been laboratory and field tested. After extraction of the adsorbed phenols with methylene chloride, the concentrated extract was analyzed by capillary column gas chromatography coupled with a flame ionization detector or a mass spectrometer. For a 3L air sample, the method has a detection limit for phenol, cresols, alkyl‐substituted phenols and xylenols of 0.3 mg/m3 using gas chromatography with flame ionization detection (GC/FID) analysis and 0.07 mg/m3 using gas chromatography mass spectroscopy/selected ion monitoring GC‐MS/SIM. Evaluation tests conducted in the laboratory indicated recoveries >85% for a wide range of phenols, cresols, xylenols and other alkyl‐substituted phenols and resorcinol. Sampling conditions were established to ensure that no breakthrough occurred for a predetermined sample volume of three (3) liters even in humid atmospheres. Stability tests indicated that for storage of up to 2 weeks at 4°C, only resorcinol showed a significant reduction in sample recovery. The proposed method and NIOSH Method 3502 were compared for the determination of phenol concentrations in air samples collected at a plant processing phenolic resins. Phenol was positively identified in the XAD sample using GC‐MS/SIM and was detected at concentrations of 40–50% of the total phenols detected using NIOSH Method 3502. This difference is attributed to the airborne paniculate matter which is known to contain bisphenols that will contribute to the total phenolic content sampled in Method 3502, but not on the XAD sample. 相似文献
5.
甲酚异构体在活性炭上的吸附与解吸平衡特性 总被引:1,自引:1,他引:1
以邻、间、对甲酚为模拟废水,考察甲基的取代位置对吸附和解吸特性的影响,并以此评价活性炭吸附生物再生工艺处理甲酚废水的可行性.平衡数据经Freundlich模型拟合后表明,活性炭(AC)对3种甲酚的吸附能力由大到小的顺序为:对甲酚>邻甲酚>间甲酚,与pKa呈正相关,与可溶性和氧化电极电位呈负相关;解吸能力由大到小的顺序为:邻甲酚>间甲酚>对甲酚,与沸点和黏度呈负相关.此外,对比吸附和解吸平衡曲线,发现吸附不可逆性是两曲线差异的重要原因,并结合数理统计的方法推导出理论不可逆吸附量的计算方法,得到AC对邻、间、对甲酚的不可逆吸附量Qi分别为27.9、 28.5、 33.4 mg/g. 相似文献
1