碱性去活柱反相高效液相色谱法分析红霉素肟及相关化合物

采用碱性去活(BDS)C18柱分离测定了红霉素肟及相关化合物。以0.02 mol/L 磷酸氢二钾(用磷酸调pH 7.2)-乙腈-甲醇(体积比为50∶40∶10)为流动相,检测波长为210 nm,柱温为35 ℃。红霉素肟E、Z异构体及相关化合物红霉素A、红霉素A 8,9-脱水-6,9-半缩酮和红霉素A 6,9-9,12-螺缩酮五种组分分离完全,检测限(S/N=3)为6.0～24.0 ng,线性关系良好,方法准确可靠,用于实际样品分析时取得较好的效果。     

二｛桥-2,4,6-三[二(2-吡啶基)胺]-1,3,5-三嗪-N,N',N',N''｝·四氯合二锌(Ⅱ)的合成与晶体结构(英文)

The derivatives of1,3,5-triazine are a class ofim portant polydentate ligands that offer the potentialto bind m ulti-m etal ions in a certain preorganizedtrigonal spatial arrangem ent[1].These com pounds andthe related m etal com plexes could provide vers…     

能量色散X荧光分析中元素间效应的蒙特卡罗模拟

针对能量色散X荧光分析(EDXRF)技术中元素间效应实验研究的难点问题,采用蒙特卡罗方法对基于Si（PIN）探测器的EDXRF系统建立模拟模型,并对模拟微束软X射线注量谱建立了高斯展宽算法。对Fe-Ni样品进行模拟计算,表明经该算法展宽后的注量谱与实测K系特征X射线谱吻合度较高,并得到了各元素特征X射线归一计数与元素含量关系曲线,结果表明该方法可自行校正EDXRF中元素间效应,获得准确的元素K系特征X射线谱理论强度。     

飞秒激光烧蚀镍钛形状记忆合金的蚀除机理

结合双温模型的分子动力学模拟方法,研究了飞秒激光脉冲辐照B2结构镍钛合金时烧蚀阈值附近的靶材蚀除机制,数值模拟了中心波长为800 nm,脉宽为100 fs,能量密度为25~50 mJ/cm2的激光与90 nm厚B2结构镍钛合金薄膜相互作用过程。确定了脉宽为100 fs的脉冲激光与镍钛形状记忆合金相互作用的烧蚀阈值,发现烧蚀阈值条件下,靶材的蚀除机制是单纯基于应力作用的机械破碎;烧蚀阈值附近,未蚀除靶材受热影响发生无序化相变的区域较小,且随激光能量密度的降低而减小。 提高激光功率密度,烧蚀同时呈现热机械蚀除和机械破碎机制。     

Arificial Leaves for Solar Fuels

Large amounts of anthropogenic CO2 emissions asso-ciated with increased fossil fuel consumption have led to global warming.Upgrading CO2 and water into solar fu...     

云纹干涉条纹倍增方法研究

本文将云纹干涉法与载波法、倍增技术相结合,提出一种位移场和应变场云纹干涉条纹倍增方法,该方法使得云纹干涉法测量灵敏度提高四倍以上。文中对该方法给出了严格的理论推导和实验验证。     

电感耦合等离子体原子发射光谱法在稀有难熔金属及其合金分析中的应用

综述了电感耦合等离子体原子发射光谱法(ICP-AES)在钨、钼、钽、铌、钛、锆等稀有难熔金属及其合金分析方面的应用情况(引用文献52篇)。     

Thermoelectric Properties and Stability of Nanocomposites Type I Clathrate Ba-Cu-Si with SiC

Thermoelectric (TE) materials attract interest for the capability of converting waste heat into electricity. Nanostructuring is considered as an effective approach to improve the conversion efficiency by reducing the lattice thermal conductivity. Nanostructured materials are metastable due to the high interface energy of grain boundaries, therefore they lose easily the nanostructure features during the thermal cycling at high temperatures, i.e., showing instabilities in TE properties. Here we show the structural/microstructural stability of type I clathrate nanocomposites in the Ba-Cu-Si system with SiC as the secondary phase. SiC has no influence on the crystal structure of the type I clathrate and very limited contributions to the grain size reduction and size-growth prevention during the ball milling and hot pressing processes, but stabilizes the TE properties during thermal cycling. A high bulk density and as low as possible contamination in nanocomposites are essential for high TE performance and high stability in nanostructured materials.     

On the limits of a class of sequences

The matrix diagonalization method is used to solve a limit problem.