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本研究应用XAD树脂富集,色谱/质谱联机分离鉴定的方法。对大骨节病病区(麟游县天堂村)三种饮水与对照(西安医科大学校园)深井水作了痕量有机化合物的测定分析。从天堂河水、深机井水、窑水与对照水样中分别检出了40种、31种、19种和10种有机化合物,且对每种检出物的结构式、分子量和峰面积均作了分析测定。其中芳核化合物分别为25种、19种、8种和4种。病区三种水样中均检出了烯类、烯酮类、酮类和萘类、苯并噻唑等稠环芳烃化合物;仅在河水和深井水样中检出了茚类化合物;在对照水样中未发现上述有机物。此结果未见文献报导。上述诸有机化合物可能是值得重视的可疑病因因素,但其真正的病因流行病学意义尚需进一步研究探讨。 相似文献
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The study inspects the traffic-induced gaseous emission dispersion characteristics from the urban roadside sites in Delhi, India. The concentration of pollutants viz. CO, NO2 and SO2 along with traffic and ambient atmospheric conditions at five selected local urban road sites were simultaneously measured. A developed General Finite Line Source Model (GFLSM) was used to predict the local roadside CO, NO2 and SO2 concentrations. A comparison of the observed and predicted values emission parameters using GFLS model has shown that the predicted values for SO2, CO and NO2 at all the selected local urban roadside locations are found to lie within the error bands of 5%, 6%, and 7% respectively. A high level of agreement was found between the monitored and estimated CO, NO2 and SO2 concentration data. From the study, it has also been established that the developed model exhibits the capability of reasonably predicting the characteristics of gaseous pollutants dispersion from on-road vehicles for the urban city air quality. 相似文献
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在运用热脱附-气相色谱/质谱(TD-GC/MS)联机技术分析杨木粉末无胶温压成形复合材料在4,60,90和160℃等4个环境温度点的挥发物总离子流图的基础上,采用色谱峰面积归一化法鉴定出杨木粉末基复合材料在各温度下的保留时间及峰面积,进而评价杨木粉末基复合材料的环境友好性。结果表明:在不同温度下,杨木粉末基复合材料挥发物中的有益成分含量明显多于有害成分,在40,60和160℃时,有益成分含量为有害成分含量的6倍以上,90℃时有益成分为有害成分的29倍,环境友好性良好;杨木粉末基复合材料总挥发物种类及有益成分种类、有害成分种类与杨木原粉相应种类大致相当,但有益成分明显增多,有害成分减少,增减幅度较大。说明这类杨木粉末基复合材料不仅无胶温压成形工艺具有环境友好性,且其制品的制备和使用过程都具有环境友好性。 相似文献
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随着信息时代的来临,利用信使服务在网络上进行广告宣传已经非常普遍,它改变了过去传统的宣传方式,但是随着技术的发展以及人们安全意识的提升,普通的发送技术已经收效甚微,但是利用系统漏洞通过缓冲区溢出技术完全可以突破这种限制,达到强行推送信使的目的。 相似文献
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阐述FTP基本原理,以VB和MS Winsock控件为工具,举例说明FTP客户端编程的一般方法. 相似文献
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A sensitive and reliable liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS) method was established to simultaneously quantitate four categories of compounds (isoflavonoids, flavonoids, alkaloids and saponins) in Gegen-Qinlian decoction (GQD). These compounds were separated by a Shiseido CAPCELL PAK C18 column with a linear gradient consisting of 0.1% (v/v) formic acid in water (A) and 0.1% (v/v) formic acid in acetonitrile (B), and delivered at a flow rate of 0.3 mL/min. All the analytes were determined by electrospray positive ionization tandem mass spectrometry in a multiple reaction monitoring (MRM) mode. Linearity, accuracy, precision, recovery and stability of the method were evaluated with the validation over the range of 4.0-538 5 ng/mL. The proposed method was applied to the analysis of a Chinese herbal preparation GQD successfully. 相似文献
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IntroductionThemainfeatureoftheC-DTListhatithasaphaseerrordetectorwithlinearcharacteristics,whichmeansthatithasawiderlock-inr... 相似文献