利用硅胶管采集空气中甲醇的气相色谱测定法

本文报道了以硅胶管采集空气中甲醇的热解吸气相色谱测定法。甲醇浓度为25mg/m~3(相对湿度>90％)时穿透量0.03mg/100mg硅胶;解吸效率100％。含20μg甲醇的硅胶管,室温放置实验第15日的平均回收率85.4％。采气体积0.5L,热解成100ML,进样量1.0ML条件下,最低检出尝试3.0mg/m~3。本法与大注射器采样法的测得结果无显著性差异。现场测定峰型与标准峰型一致。方法具有穿透量适宜,解吸效率高,采样后硅胶管稳定时间长,精密度,灵敏度高等特点。     

大口径毛细管气相色谱法测定蔬菜水果中农药残留量

用大口径毛细管柱为分离柱，测定蔬菜、水果中有机磷农药残留量。试验结果：有机磷农药回收率为84.1%-101.8%，最低检出浓度为2-8цg/kg。证明该法分离效果好，分析时间短，所得结果可以满足国际分析方法要求。     

交联聚乙烯亚胺螯合树脂对二价铜离子的吸附性能研究

考察了交联聚乙烯亚胺螯合树脂对溶液中铜离子的吸附性能,开展了饱和吸附容量、等温吸附曲线、PH影响曲线以及吸附速度测定等实验.结果表明,此交联螯合树脂对溶液中铜离子具有吸附能力强、吸附速度快等特点,可望用于含铜废水的处理及回收.     

Experimental Research on Atmospheric Electric Field and Extensive Air Shower Particle Increasing During Thunderstorms with ARGO-YBJ

From April lst to August 14th, 2006, thunderstorms had been recorded at Yangbajing Cosmic Ray Observatory by ARGO-YBJ experiment. This paper analyzed the correlation between atmospheric electric field (AEF) and "scaler mode" counting rate during thunderstorm. Counting rates of multiplicities n = 1,2 were found to have a large increase ( from 1.02% to 9.03% ), while there was few or no changes in those of multiplicities n =3 and n≥4 during the thunderstorms. The counts of different multiplicities had different feedbacks on the violent change of AEF, which showed that their energy and most components were distinguishing.     

气缸套的离子氮化技术分析

本文应用钢铁件离子氮化的理论及生产实践经验,遵照国家离子氮化行业标准的有关要求,阐明了气缸套离子氮化的原理、过程、工艺和特点;分析了本厂气缸套离：产氮化的工艺流程及操作要点。     

高速列车DZ2车轴离子渗氮工艺研究

采用N2+H2气氛对DZ2钢的试样及车轴进行离子渗氮工艺试验,通过温度、时间、N2比例3种因素的正交试验以及三段式深层离子渗氮试验,结合OM、XRD、SEM等检测与分析,实现渗氮层组织结构及硬度梯度调控,得到优化工艺参数,并对渗氮后的表面粗糙度及残余应力进行表征.结果表明,气氛含N2比例20％以下时表面可以获得γ'单相...     

二价金属阳离子对沥青与二氧化硅表面间胶体作用力的影响

为了从微观角度探索Ca2+和 Mg2+对沥青水基提取过程的影响,在1 mmol/L KC1溶液中加入不同浓度的Ca2+和 Mg2+,调节pH值,采用原子力显微镜检测SiO2与沥青表面间的胶体作用力.当溶液pH值分别为3.5,5.5和8.5时,随着Ca2+或Mg2+浓度的增加,沥青与SiO2表面间的长程排斥力减小,表面电...     

硫酸镁对重型颅脑损伤患者血清IL1β、TNFα浓度的影响

目的 研究硫酸镁对sTBI患者血清IL1β和TNFα浓度的影响,进一步探讨镁离子保护创伤神经元的机制.方法 将入选病例随机分为治疗组和对照组,每组30例.对照组按常规治疗,治疗组加用硫酸镁.正常组20例,为成年健康献血员.按预设时间抽取肘静脉血,采用原子分光光度法和放射免疫法分别测定血清Mg2+与IL1β、TNFα浓度.应用SPSS13.0软件包分析数据.结果 sTBI后血清IL1β和TNFα浓度24h内即明显升高,3d达到高峰,以后逐渐下降;治疗组患者血清IL1β浓度于伤后2、3、7d和TNFα于伤后2、3d明显低于对照组(P<0.01或P<0.05).结论 sTBI患者伤后早期即出现血清IL1β和TNFα浓度升高;早期应用硫酸镁治疗能明显抑制sTBI患者急性期炎症反应,保护神经功能.     

Effect of acidity of drugs on the prediction of human oral absorption by biopartitioning micellar chromatography

Biopartitioning micellar chromatography (BMC) is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption, which can mimic the drug partitioning process in biological systems. In this paper, a data set of 56 compounds representing acidic, basic, neutral and amphoteric drugs from various structure classes with human oral absorption (HOA) data available were employed to show the effect of acidity of drugs in oral absorption prediction. HOA was reciprocally correlated to the negative value of the capacity factor (kBMC) determined by BMC at pH 7.4 and 6.5. The relationships between kBMC and the corresponding HOA values of all compounds were rather poor, but the correlations were improved when the acidity of drugs was taken into consideration. Moreover, the proposed models allowed obtaining of good predictive values for both highly and poorly absorbed compounds. It is demonstrated that the constructed models derived from compounds with the same kind of charge property are of more practically meaningful and rigorous.