人为土中纳米颗粒的发生、结构和矿物相

Soils contain various kinds of crystalline to amorphous solid particles with at least one dimension in the nanoscale (<100nm). These nanoparticles contribute greatly to dynamic soil processes such as soil genesis, trace element cycling, contaminant transport, and chemical reaction. The nano-sized fraction of an Anthrosol was obtained to determine the occurrence, chemical composition, structure, and mineral phases of nanoparticles using high-resolution transmission electron microscopy (HRTEM) equipped with an energy-dispersive X-ray spectroscopy. Selected area electron diffraction or the fast Fourier transform of high-resolution images was used in structural characterization of the nanoparticles with HRTEM. Two nanoscale mineral types, i.e., mineral nanoparticles and nanominerals, were observed in the Anthrosol. Mineral nanoparticles in soil included well crystalline aluminumsilicate nanosheets, nanorods, and nanoparticles. Nanosheets with a length of 120-150 nm and a width of about 10-20 nm were identified as chlorite/vermiculite series. The presence of clear lattice fringe spacing in HRTEM image of nanoparticles indicated that mineral nanoparticles had a relatively good crystallinity. The nanomineral ferrihydrite also existed in the Anthrosol. The HRTEM images and the particle size distribution histogram suggested that these ferrihydrite nanoparticles were quite homogeneous, and had a narrow size distribution range (1-7 nm) with a mean diameter of 3.6±1.6 nm. Our HRTEM observation indicated that mineral nanoparticles and nanominerals were common and widely distributed in Anthrosols. HRTEM and selected area diffraction or lattice fringe spacing characterization provided further proofs to the structure of nanoparticles formed in soil.energy-dispersive X-ray spectroscopy (EDS), ferrihydrite, high-resolution transmission electron microscopy (HRTEM), nanominerals, nano-sized fraction     

两系杂交水稻种子贮藏后的纯度鉴定

采用超薄等电聚焦电泳技术研究了经不同贮藏时期的两系杂交水稻F1种子中父本特征蛋白质带的变化情况。结果表明,贮藏了0-12个月的F1种子中父本特征蛋白质带依然清晰,而贮藏了18个月后,部分F1种子中的父本特征蛋白质带变得模糊。所以,贮藏一年以内的F1种子还能用超薄等电聚焦电泳技术鉴定纯度,而贮藏18个月以上的F1种子则不能继续用超薄等电聚焦电泳技术鉴定纯度。     

中国纯血马血红蛋白多态性的遗传分析

采用等电聚焦电泳对１７５匹中国纯血马幼驹进行了血红蛋白多态性的检测。结果发现该位点共有３种基因型,由２个等位基因Ｈｂ＾ＢＩ控制。基因型ＢⅡ和ＢⅠ／ＢⅠ的频率分别为０．６７４３,０．２８５７和０．０４００,其中纯合型ＢⅡ／ＢⅡ为优势基因型。基因频率Ｈｂ＾ＢＩ为０．８１７１,Ｈｂ＾ＢＩ为０．１８２９。通过计算得出该位点的个体识别概率为０．４６２和亲仔关系排除概率为０．１２７。     

老年性白内障囊外摘出并人工晶体植入术后视力低下的分析

分析老年性白内障囊外摘出并人工晶体植入术后眼视力低下的原因及防治。方法对老年性白内障囊外摘出并人工晶体植入术的患者,出院时的６２５例８０５眼和２个月后复诊的１８例２１０眼进行检查,对裸眼视力〈０．５者的原因进行统计分析。结果裸眼视力〈０．５者,出院组２３６眼,（２９．３％）,其中因术前原有眼病所致的１９例,因手术用光,过矫或欠矫等２１７眼;随诊组４３组,后囊混浊２２眼,散当、过中欠矫１４眼,角膜失     

报废汽车回收X射线分选技术研究进展与应用

介绍了X射线分选的具体原理,指出了目前X射线分选存在的问题,综述了国内外报废汽车回收X射线分选的研究进展与相关设备应用现状,展望了X射线分选技术的发展趋势.     

青海不同产区大黄的X-射线衍射图谱研究（摘要）

[目的]为区分不同产地大黄药材的质量及鉴别提供依据。[方法]将供试材料青海玉树掌叶大黄（样品1）、青海海南唐古特大黄（样品2）与青海果洛唐古特大黄（样品3）分别粉碎成粉末,过100目筛,即可供X射线衍射试验用。设定管压30 kV,管流20 mA,2θ扫描范围3°～90°,扫描速度0.06°/s,每种样时间0.5 s,获得3种不同产区大黄的X-射线衍射图谱。试验数据以晶面间距d与特征峰相对强度L/Io表示,记为d/（I/Io）。将试验数据导入中药指纹图谱相似度计算软件,经选峰,设定匹配模板,将谱峰自动匹配,然后设定标准模板,进行谱峰差异性评价和整体相似性评价。[结果]样品1中所含的化学成分与样品2相同,但峰的强度（I/Io）不同,表明相同成分在两种样品中的含量不相等。同样把样品3的图谱与其他两个样品进行比较,也会得到相同的衍射峰值。表明不同产区的大黄中各化学成分的含量有差异,但其衍射图谱及衍射峰值具有一定的指纹特征。[结论]X-射线衍射法是鉴别不同产区的大黄及其他中药材的一种快捷有效的方法。