海外新产品：VACISγ-射线多功能车辆与货柜检查系统专辑

车辆与货柜检查系统(VACIS)是一种利用γ-射线的成象系统,它是利用一个窄条状的γ-射线束照射到一系列线状排列的检测器来成象的。这种检查系统有两种类型的结构。一种是检查系统能移动来扫描一辆静止不动的车,另一种检查系统是固定的让要扫描检查的车辆移动检查系统。     

北偏西大风对北京冬季生物气溶胶的影响

生物气溶胶对大气成云过程、生态系统演化和人体健康都有着重要的影响,目前对生物气溶胶浓度、组成和活性的变化规律认识不足.因此,在2013年1月和2015年1月在北京市清华大学校园内进行了采样和观测,以分析气象条件对生物气溶胶浓度和组成的影响.生物气溶胶浓度用生物气溶胶在线检测器WIBS-4A(waveband integrated bioaerosol sensor)测定,生物气溶胶中细菌群落的组成用16S rDNA测序的方法来测定.结果表明,北京冬季生物气溶胶数浓度范围在2~150 L~(-1).风是影响生物气溶胶的浓度和组成的重要因素.主导风向为北偏西30°,风速大于4 m·s-1的大风天气时,生物气溶胶的数浓度升高1个数量级,生物气溶胶中细菌群落的组成也发生急剧的变化.大风天气过后,生物气溶胶中细菌群落的组成缓慢恢复到大风前的状态.     

Improved preparation and identification of aristolochic acid-DNA adducts by solid-phase extraction with liquid chromatography-tandem mass spectrometry

Aristolochic acid (AA) is a known nephrotoxin and potential carcinogen, which can form covalent DNA adducts after metabolic activation in vivo and in vitro. A simple method for preparation and characterization of aristolochic acid-DNA adducts was developed. Four AA-adducts were synthesized by a direct reaction of AAI/AAII with 2’-deoxynucleosides. The reaction mixture was first cleaned-up and pre-concentrated using solid phase extraction (SPE), and further purified by a reversed-phase high performance liquid chromatography (HPLC). By the application of developed SPE procedure, matrices and byproducts in reaction mixture could be greatly reduced and adducts of high purity (more than 94% as indicated by HPLC) were obtained. The purified AA-DNA adducts were identified and characterized with liquid-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-Q-TOF-MS/MS) and LC-Diode array detector-fluorescence (LC-DAD-FL) analysis. This work provides a robust tool for possible large-scale preparation of AA-DNA adduct standards, which can promote the further studies on carcinogenic and mutagenic mechanism of aristolochic acids.     

气相色谱法测定水中甲萘威

通过改进预处理方法,采用带氮磷检测器的毛细柱气相色谱仪测定水中甲萘威的含量,得到了较好的精密度和准确度。     

Improved method for analyzing the degradation of estrogens in water by solid-phase extraction coupled with ultra performance liquid chromatography-ultraviolet detection

We established an improved method for the determination of four estrogens including estriol (E3), 17 -estradiol (E2), 17 -ethynylestrodiol (EE2) and estrone (E1) in water. The method consisted of solid-phase extraction (0.5 L water) and subsequent analysis of analytes by ultra-performance liquid chromatography (UPLC) with an ultraviolet detector (UVD). Base-line separation was achieved for all studied estrogens using a column (50 mm 2.1 mm) packed with 1.7 m particle size stationary phase. Recovery was higher than 88% and detection limits ranged between 12.5–23.7 ng/L for the four estrogens, with the RSD ranging from 7% to 11%. The method was successfully applied to determine E2 and EE2 in simulated natural water, which found that about 70% of E2 was degraded (with a half-life of about 30 hr) within 48 hr and about 55% of EE2 was degraded (with a half-life of about 36 hr). Low levels of E1 were found, however E3 was undetectable during the process.     

气相色谱-电子捕获检测法在线观测12种卤代温室气体

利用自组装的气相色谱仪-电子捕获检测器系统(GC-ECD)测定大气中12种卤代温室气体,空气样品采样的时间分辨率80min,分析精度0.16%—4.87%,准确度-1.64%—3.05%.对2007年4月6日—2007年4月16日在北京上甸子站的观测结果进行分析,获得12种卤代温室气体的本底和非本底浓度,表明该系统适用于大气中卤代温室气体浓度在线观测。     

溢油指示物（或指标）的GC—FID研究

应用气相色谱氢焰离子化检测器（GC－FID）分析环境溢油，给出了GC－FID鉴别溢油的指示物（或指标）。结果表明，在溢油指示物（或指标）的研究中，气相色谱法（GC－FID）是一种快速有效的方法。     

离子色谱法测定地下水中碘离子

建立毛细管离子色谱-积分安培检测法测定地下水中碘离子的方法.样品经0.20 μm滤膜过滤后注入离子色谱仪,采用IonPac AS16阴离子交换分离柱分离,62.5 mmol/L NaOH溶液梯度洗脱,由安培检测器积分安培检测模式定量检测.方法检出限为0.20 μg/L,线性范围5～100μg/L,相关系数0.9999.重现性良好,相对标准偏差小于0.6％(n=9).加标回收率为91.2％～106.0％.     

乙腈盐析萃取HPLC-PDA同时测定水中11种苯胺类化合物

通过对色谱分析和样品萃取条件的选择和优化,建立了同时分析水中11种苯胺类化合物的HPLC方法。样品经乙腈盐析萃取后直接进样分析,采用 ODS色谱柱,以乙腈-水为流动相进行梯度洗脱,用PDA检测。结果表明,11种苯胺类化合物在0.20~100mg/L范围内其浓度和检测信号呈良好的线性关系,方法检出限为0.002~0.007mg/L,地表水和废水样品加标回收率为81.6%~97.4%,相对标准偏差为1.5%~5.5%。