Solvent co-distillation was employed to isolate and collect the aroma compounds of tobacco,which were then determined by GC/MS.The major aroma compounds in the isolated mixture were quantified with the internal standard(methyl nicotinate) added.Compared with the simultaneous distillation extraction(SDE),the solvent co-distillation was fast,convenient,and easy to operate.The repeatability was satisfactory.The obtained result was comparable to those obtained from SDE.
High resolution capillary gas chromatographic(GC)fingerprint was used to detect major constituents in cut tobacco.Trimethylsilylation was used to improve the separation and detection of constituents.Chromatogram data were analyzed by PCA method combined with GC fingerprint.Results indicated that this method provided more sensitive information of the complicated GC data and could be used as an assistant method to evaluate cigarette quality.
Various studies proved that the smoking quality of cigarettes are not merely decided by one or several kinds of chemical components, the aroma and flavor perceptions of a cigarette are the combined results from multi-components of cigarette smoke. Methods of data processing such as chromatograms subtraction, pattern recognition based on principal components analysis (PCA), factor analysis and cluster analysis had been applied for the cigarette smoke evaluation. However the fingerprint total abnormal index (TAI) method hasn't been reported in this field. In this paper, The TAI method combined with high resolution capillary gas chromatographic analysis of cigarette smoke was used to analyze the cigarette smoke. The TAI represents the difference between two cigarette smoke fingerprint chromatograms, includes abnormal index of common, absent and excess chromatographic peaks. Finally, the TAI was successfully employed in the processing of GC data for cigarette smoke and the examples were given. The chromatograms of twelve brands cigarettes including Virginia-type, British flue-curing type and American blended-type were collected and the TAI of every chromatogram was calculated with a Virginia-type cigarette as standard. The TAI method was compared with PCA and chromatograms subtraction methods, the results indicated that the TAI provides more useful information of the complicated GC data.
<span id="ChDivSummary" name="ChDivSummary" class="abstract-text"><正> 肺功能障碍是尘肺的主要症状之一。为了解铸工尘肺肺功能损伤情况,本文对不同期次的铸工矽肺肺功能和小气道功能进行了调查。 1 对象与方法 1.1 调查对象调查对象为上海机电管理局所属企业的翻砂、清砂、铸铁、造型等作业100例男性不同期次的矽肺患者。对照组为无尘毒接触史男性健康</span>
> 电镀铬的过程中形成的铬酸雾,可对人体产生危害。急性吸入表现为刺激性损伤(引起喷嚏,咳嗽,头痛,鼻腔分泌物增多,甚至呼吸困难),长期接触铬可表现为腐蚀性损害(皮肤铬疮,手指畸形,以及鼻中隔粘膜糜烂、溃疡甚至穿孔)。近年来有资料表明,从事铬作业的工人其肿瘤发病率有增高的趋势,主要
