| 查看: 197 | 回复: 1 | |||
| 当前主题已经存档。 | |||
[交流]
翻译一段化学类英语~
|
|||
| A rapid and reliable analytical method is presented for the determination of trace amounts of benzo[a]pyrene（苯并[a]芘） in roasted coffee, coffee brew, and spent grounds. Roasted coffee and spent grounds were extracted with acetone, followed by saponification and cyclohexane extraction. Coffee brew was extracted three times with cyclohexane, and the combined extracts were purified by chromatography on a silica gel column. The extracts were analyzed by HPLC with a 5-pm Vydac reversed-phase 201 TPB 5 column and fluorescence detection under isocratic conditions. The benzo[a]pyrene levels in 55 roasted coffee samples, commercially available in The Netherlands, ranged from not detectable (<0.1 pg/kg) to 0.5 bg/kg. Coffee brews were prepared by two different methods from an over-roasted coffee sample with an elevated benzo[a]pyrene level of 2 pg/kg. These brews yielded benzo[a]pyrene contents of approximately 1 ng/L, indicating benzo[a]pyrene extraction yields of about 1% for both coffee preparation methods. |
回复此楼» 猜你喜欢
酰胺脱乙酰基
已经有9人回复
-
有时候真觉得大城市人没有县城人甚至个体户幸福
已经有3人回复
-
CSC & MSCA 博洛尼亚大学能源材料课题组博士/博士后招生｜MSCA经费充足、排名优
已经有5人回复
-
有70后还继续奋斗在职场上的吗？
已经有6人回复
-
博士延得我，科研能力直往上蹿
已经有7人回复
-
退学或坚持读
已经有27人回复
-
面上基金申报没有其他的参与者成吗
已经有5人回复
-
遇见不省心的家人很难过
已经有22人回复
xiaoqihu
铁杆木虫 (著名写手)
- 翻译EPI: 88
- 应助: 1 (幼儿园)
- 贵宾: 0.005
- 金币: 9724.8
- 散金: 7
- 红花: 4
- 帖子: 1337
- 在线: 105.6小时
- 虫号: 590066
- 注册: 2008-08-31
- 专业: 有机合成
carloslangel(金币+19): 2010-03-01 20:13
|
这里展现了一个快速可信赖的检测烘烤咖啡豆，调制咖啡和咖啡残渣里痕量的benzo[a]pyrene的分析方法。烘烤的咖啡豆和咖啡残渣用丙酮萃取，皂化后用环己烷萃取。调制咖啡用环己烷萃取3遍，合并萃取液后用硅胶柱色谱提纯。萃取物用高效液相色谱分析，采用5pm Vydac 反相 201 TPB 5 柱，荧光监测，梯度洗脱。 55个烘烤咖啡（荷兰生产）样品中benzo[a]pyrene的含量从小于0.1pg每公斤到0.5g每公斤。用两种方法制备的过度烘烤的调制咖啡样品中 benzo[a]pyrene的含量提高了2pg每公斤。从这些调制咖啡所得到的 benzo[a]pyrene的含量约为1ng每升，这表明通过两种制备方法得到的 调制咖啡内benzo[a]pyrene大概都为1% roasted coffee指的是烘烤的咖啡豆磨的咖啡粉 coffee brew指的是用咖啡粉煮得的咖啡 spent grounds指的是调制完咖啡剩下的咖啡粉残渣 |
2楼2010-03-01 19:55:39