期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
Natural Gas and Indoor Air Pollution: A Comparison With Coal Gas and Liquefied Petroleum Gas
1
作者 YUEZHANG BAO-SHENGCHEN +3 位作者 GUANG-QUANLIU JU-NINGWANG ZI-IEN-HUAZHAO LIAN-QINGLIN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第3期227-236,共10页
Objective The study was designed to compare the combustion products of coal gas, liquefied petroleum gas and natural gas in relation to indoor air pollution. Methods Regular pollutants including B(a)P were monitored a... Objective The study was designed to compare the combustion products of coal gas, liquefied petroleum gas and natural gas in relation to indoor air pollution. Methods Regular pollutants including B(a)P were monitored and 1-hydroxy pyrene were tested in urine of the enrolled subjects. Radon concentrations and their changes in four seasons were also monitored in the city natural gas from its source plant and transfer stations to final users. To analyze organic components of coal gas, liquefied petroleum gas and natural gas, a high-flow sampling device specially designed was used to collect their combustion products, and semi-volatile organic compounds contained in the particles were detected by gas chromatograph-mass spectrograph (GC/MS). Results Findings in the study showed that the regular indoor air pollutants particles and CO were all above the standard in winter when heating facilities were operated in the city, but they were lowest in kitchens using natural gas; furthermore, although NO2 and CO2 were slightly higher in natural gas, B(a)P concentration was lower in this group and 1-hydroxy pyrene was lowest in urine of the subjects exposed to natural gas. Organic compounds were more complicated in coal gas and liquefied petroleum gas than in natural gas. The concentration of radon in natural gas accounted for less than 1‰ of its effective dose contributing to indoor air pollution in Beijing households. Conclusion Compared to traditional fuels, gases are deemed as clean ones, and natural gas is shown to be cleaner than the other two gases. 展开更多
关键词 Natural gas Indoor air pollution Organic compounds RADON 1-hydroxy pyrene Environmental monitoring
下载PDF
披针叶茴香果实的化学成分研究 被引量:8
2
作者 李慧娟 王丽霞 +3 位作者 刘孟奇 张雁冰 毕跃峰 柳继锋 《中国药学杂志》 CAS CSCD 北大核心 2014年第8期636-639,共4页
目的研究八角科(Illiciaceae)植物披针叶茴香(Illicium lanceolatum)果实的化学成分。方法应用硅胶、Sephadex LH-20、MCI等各种色谱技术进行分离纯化,根据化合物的理化常数和波谱数据鉴定其结构。结果从披针叶茴香果实的体积分数9... 目的研究八角科(Illiciaceae)植物披针叶茴香(Illicium lanceolatum)果实的化学成分。方法应用硅胶、Sephadex LH-20、MCI等各种色谱技术进行分离纯化,根据化合物的理化常数和波谱数据鉴定其结构。结果从披针叶茴香果实的体积分数95%乙醇提取物中分离得到12个化合物,通过渡谱数据和理化常数分别鉴定为2,4-dihydroxy—allylbenzene-2-O-β-D—glucopyranoside(1),(+)-儿茶素(2),槲皮素-3-O-β-L-鼠李糖苷(3),芦丁(4),异鼠李素-3-D-β-D-芸香糖苷(5),6-deoxy-1-hy—droxy neoanisatin(6),莽草毒素(7),icarisideE3(8),(75,8R)-urolignoside(9),对羟基苯甲酸(10),莽草酸(11),β-谷甾醇(12)。结论化合物1,4~6,8~10为首次从该植物中分离得到。 展开更多
关键词 八角属 披针叶茴香 2 4-dihydroxy—allylbenzene-2-O-β-D—glucopyranoside 芦丁 异鼠李素-3-O-β-D-芸香糖苷 6-deoxy-1-hydroxy neoanisatin
原文传递
An Alternative Method for Anomeric Deacetylation of Per-acetylated Carbohydrates
3
作者 李玉文 李英霞 +1 位作者 张伟 管华诗 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第1期117-118,共2页
An alternative method for anomeric deacetylation of fully acetylated carbohydrates has been developed using imidazole in methanol.
关键词 acetylated 1-hydroxy sugar anomeric deacetylation IMIDAZOLE
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部