硫磺制模法提取雪地足迹的优势

目的比较硫磺制模法与石膏制模法提取雪地足迹的效果。方法分别用两种制模法实验,观察比较操作流程、制模时间、细节特征反映等方面。结果硫磺制模法在雪地足迹提取的速度、细节特征反映等方面优于石膏制模法。结论与传统的石膏制模法相比,硫磺制模法更加迅速、简便,在细节特征的反映更加清晰。     

Prudence Required in Limiting Coal Imports

正Recently,the news that the National Development and Reform Commission(NDRC)will soon release provisional management rules on coal quality has sparked discussions in the market.According to a draft the NDRC has issued for public consideration,the country will limit imports of coal with heat value below 4,554 kilocalories,sulfur content higher than 1 percent or ash content above 25 percent.The policy remains to be discussed.With regard to resource     

Discriminating Hodgdon Pyrodex® and Triple Seven® Using Gas Chromatography–Mass Spectrometry

Abstract: Pyrodex ^® and Triple Seven ^® are black powder substitutes that often find use as fillers in improvised explosive devices, such as pipe bombs. These propellants have essentially the same overall appearance and oxidizers, but different fuels. For example, Pyrodex ^® contains sulfur, sodium benzoate, and dicyandiamide (DCDA), whereas Triple Seven ^® lacks sulfur but also contains 3‐nitrobenzoic acid. In this method, intact particles and postblast solid residues were reacted with bis(trimethylsilyl)trifluoroacetamide + 1% trimethylchlorosilane in acetonitrile for 30 min at 60°C. The resultant trimethylsilyl derivatives of the organic fuels were then analyzed by gas chromatography–mass spectrometry. Each derivative was clearly resolved from other components, and high‐quality mass spectra were obtained. In addition, characteristic fragments resulting from loss of a methyl radical from the molecular ion (m/z 163 for sulfur, m/z 171 for DCDA, m/z 179 for benzoic acid, and m/z 224 for nitrobenzoic acid) were able to be monitored.     

钼和铜对小鼠抗氧化机能的影响

在 3组昆明系小白鼠基础日粮中分别添加高剂量的Mo S、Mo S Cu和Cu ,饲喂 60d和 1 2 0d后 ,分析各组小白鼠肝组织中Mo、Cu、Se、Zn的含量变化 ,并通过检测组织中GSH Px活力和MDA含量 ,探讨饲料中添加过量的Mo、Cu和S ,对机体抗氧化机能的影响。结果表明 ,日粮中同时添加过量Mo S、Mo S Cu后 ,组织中Mo、Cu水平并不升高反而降低 ;添加这 3种元素之后 ,肝Zn水平下降明显 (P <0 .0 5 ) ;而添加Mo S后第 1 2 0d时 ,肝Se水平也会降低 ;添加Mo后 ,组织中GSH Px活力会代偿性升高 ,MDA的浓度明显增加。由此可见 ,饲料中同时添加过量Mo和S或Mo、Cu和S后 ,并不会导致动物Mo中毒     

一种全新的燃煤锅炉排气净化法

从理论上分析燃煤锅炉不用添加剂在排气的同时,达到除尘、脱硫和脱一氧化氮的效果,并介绍了该净化法的特点。     

传统硫熏加工与现代微波加工滁菊质量比较

目的 通过对硫熏加工滁菊和微波加工滁菊中主要化学成分进行比较,为滁菊的合理加工方法提供依据.方法 以挥发油、总黄酮、绿原酸及二氧化硫残留量为检测指标,对两种方法加工的滁菊的主要化学成分进行比较分析.结果 硫熏滁菊中挥发油、绿原酸含量均高于微波滁菊;硫熏滁菊中总黄酮的含量略低于微波滁菊;硫熏滁菊的薄层色谱斑点数与微波滁菊...