Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni.     

Synthesis of TiO2 supported on activated carbon by MOCVD:operation parameters study

A novel metallo-organic chemical vapor deposition (MOCVD) technique has been applied to the preparation of the photocatalytic titanium dioxide supported on activated carbon. The effects of various condition parameters such as carrier gas flow rate, source temperature and deposition temperature on the deposition rate were investigated. The maximum deposition rate of 8.2 mg/(g.h) was obtained under conditions of carrier gas flow rate of 400 ml/min, source temperature of 423 K and deposition temperature of 913 K. The deposition rate followed Arrhenius behavior at temperature of 753 K to 913 K, corresponding to activation energy Ea of 51.09 kJ/mol. TiO2 existed only in anatase phase when the deposition temperature was 773 K to 973 K. With increase of deposition temperature from 1073 K to 1273 K, the rutile content sharply increased from 7% to 70%. It was found that a deposition temperature of 773 K and a higher source temperature of 448 K resulted in finely dispersed TiO2 particles, which were mainly in the range of 10-20 nm.     

鬼针草的研究现状与应用前景

针对近年来对鬼针草属植物研究的资料 ,系统总结了鬼针草药用成分分析 (细胞学、生药学、化学成分、药理学 )和品种的鉴定方法 ,同时对鬼针草资源进一步开发利用指出了更广阔的前景。     

2-（1，2-亚乙／1，3-亚丙二硫）亚甲基-3-羰基-N-芳（烷）基丁酰胺制备的新方法

以易制备的2-（1,2-亚乙／1,3-亚丙二硫）亚甲基-3-羰基丁酸1为原料,经与氯化亚砜的氯化反应后,与胺反应成功地以较好产率（40．5％-72．0％）合成重要的有机合成中间体2-（1,2-亚乙／1,3一亚丙二硫）亚甲基-3-羰基-N-芳（烷）基丁酰胺3．     

从国家社会科学基金项目课题指南论体育学术期刊传播的导向——以2016年国家社会科学基金项目课题指南（体育学）为例

摘要：国家社会科学基金项目课题指南正越来越深刻地影响着学术期刊编辑的选题策划,进而影响到编辑传播行为的导向。研究试图为编辑传播行为提供科学的理论指导,以体育学术期刊的传播导向为研究对象,采用综合分析法与文献资料法,以2016年国家社会科学基金项目课题指南（体育学）为例,阐述了该课题指南从体育改革与发展、体育与健康促进、全民健身、体育产业、体育法学、公共体育服务、体育传播学等领域对体育学术期刊编辑选题策划的借鉴价值及其传播行为的导向价值。体育学术期刊编辑在传播实践中,应注重参考国家社会科学基金项目课题指南,力求提升选题策划的整体质量,不断提升体育学术期刊的学术影响力与社会美誉度。该研究有助于学者与编者更精准地把握好研究方向与选题方向,进一步繁荣体育人文社会学领域的学术研究。     

核酸四碱基体及四螺旋模型的理论构建

核酸的结构具有多态性 ,核酸的功能取决于其结构 .了解核酸不同结构的特征有利于对其功能的充分认识 .本文对核酸四碱基体及其形成的四链结构模型进行了理论研究 .这些工作有助于从理论上进一步研究核酸四螺旋结构 ,对相关的实验研究也将起到有益参考作用 .     

茭白孕茭前后植株叶片和叶鞘器官中游离氨基酸和总糖含量的变化

试验比较了“河姆渡”双季茭在孕茭前和膨大期植株叶片和叶鞘中营养成分的变化。结果表明：(1)膨大期茭白叶鞘和叶片内的总糖含量分别比孕茭前显著增加99．07%和123．79%(P＜0．05);(2)膨大期,叶鞘内总糖的含量显著大于叶片中总糖的含量,增加达18．1%(P＜0．05);(3)孕茭前和膨大期相比．茭白叶片内游离氨基酸的组成和含量无显著差异;但叶鞘内游离氨基酸的组成和含量却差异显著(P＜0．05),氨基酸总量提高了127．8%;(4)膨大期与孕茭前相比,叶鞘中有6种氨基酸的含量增幅最大,依次是：谷氨酸(Glu;610．0%)＞甘氨酸(Gly;303．6%)＞丙氨酸(Ala;228．7%)＞赖氨酸(Lys;207．2%)＞丝氨酸(Ser;203．7%)＞天门冬氨酸(Asp;172．0%);其中,丝氨酸含量最高,孕茭前和膨大期分别占氨基酸总量的34．81%和46．42%;(5)膨大期与孕茭前相比,叶片和叶鞘中脯氨酸(Pro)、精氨酸(Arg)和亮氨酸(Leu)含量均有明显降低。     

急性力竭运动对大鼠血浆支链氨基酸及氨量变影响的研究

本研究选用９ 只健康成年 Ｓ Ｄ 雄性大白鼠,采用一次性力竭游泳运动方式,通过运动前及运动后即刻从心脏取血, 测定其力竭运动前后血浆尿素氮、支链氨基酸、氨的量变情况。结果表明急性力竭性运动后大鼠血浆尿素氮、支链氨基酸、氨含量均呈明显增高, 且前两者的变化差异有显著意义（ Ｐ＜ ０． ０５）。结果提示急性力竭运动后体内蛋白质分解代谢、支链氨基酸的代谢增强,血浆氨、支链氨基酸的含量变化与运动性疲劳的出现和疲劳程度有密切关系。     

构建网络环境下的CSCL应用模式

随着网络技术的深入发展和在教育教学中的广泛应用,计算机支持的协作学习逐渐成为网络教育中的一种非常重要的学习模式.Internet作为网络教育的主要媒体,为协作学习提供了有效的支持环境,构建了计算机支持的协作学习应用模式.     

接骨木果实营养成分的分析

本文利用氨基酸自动分析仪、等离子发射光谱仪和高效液相色谱仪等仪器，对接骨木果实氨基酸含量，微量元素含量营养成分进行了测定，从而为接骨木的进一步开发利用提供了营养学方面的依据。