碰撞反应池-电感耦合等离子体质谱法测定锆基合金中痕量镉

用电感耦合等离子体质谱法测定锆基合金中痕量镉。以氧气作为碰撞反应气,消除锆基体中多原子离子ZrOH对镉测定的影响。镉元素的质量浓度在5.0μg·L-1以内与其峰面积呈线性关系,检出限(3σ)为0.122μg·L-1。在0.5μg·L-1镉(Ⅱ)的水平上进行精密度试验,测定值的相对标准偏差(n=11)为2.8%。     

Structural,morphological and optoelectronic aspects of YAlO3:Dy3+ doped nanocrystalline materials for NUV energized WLEDs

Cost-effective urea assisted solution combustion (SC) synthetic method was employed to prepare a series of doped YAlO₃:xDy³⁺ (0.01–0.08 mol) phosphors. The resulting powdered samples were comprehensively examined through various structural as well as optical measurements. Rietveld refinement studies concluded that prepared nanomaterials structured into the orthorhombic system having Pbnm (62) space group. Energy dispersive spectral (EDS) analysis was executed to observe the relative proportions of constituent elements in all doped nanophosphors. Transmission electron microscopy (TEM) micrograph indicated the presence of agglomerated particles with the average size in the nano range. Photoluminescence excitation (PLE) spectra showed that the designated phosphors could be excited by near ultraviolet (NUV) energized lighting sources. The strongest emission centred at 576 nm, corresponding to electric dipole (⁴F_9/2 → ⁶H_13/2) transition of Dy(III) ion. Furthermore, characteristics photometric parameters viz. correlated color temperature (CCT), chromaticity coordinates (x and y), and color purity (%) were figure out with the aid of PL data, which strongly endorsed their usage in NUV energized WLEDs applications.     

CCT型超导组合磁体样机结构设计

基于斜螺线管型(Canted-Cosine-Theta,简称CCT)线圈结构,研制了一台四极与六极组合的超导磁体样机,它的四极和六极梯度场分别为22 T/m和120 T/m²。该组合型磁体的好场区范围为Φ0.16 m×1.3 m,有效长度为1.3 m。其中四极与六极磁体均采用两层骨架结构,每层骨架的线槽内并排放置多层多根超导线。本文根据导体轨迹,以约束电磁力为结构设计目标,设计了磁体关键部件线圈支撑骨架和磁体内外支撑结构,并介绍了磁体制造过程中的关键环节。     

Effects of N and B on continuous cooling transformation diagrams of Mo–V–Ti micro-alloyed steels

Effects of the single addition of nitrogen (N) and boron (B) and the combined addition of N and B on continuous cooling transformation (CCT) diagrams and properties of the three Mo–V–Ti micro-alloyed steels were investigated by means of a combined method of dilatometry and metallography. Microstructures observed in continuous cooled specimens were composed of pearlite (P), quasi-polygonal ferrite (QPF), granular bainite (GB), acicular ferrite (AF), lath-like bainite (LB) and martensite (M) depending on the cooling rates and transformation temperatures. Single addition of 12?ppm B effectively reduced the formation of QPF and broadened the cooling rate region for LB and M. Added N makes the action of B invalid and the QPF region was prominently broadened, and even though the cooling rate is higher than 50°C?s^?1, it cannot obtain full bainite.     

微波消解-ICP-MS法同时测定木薯淀粉中铅、铜、镉、砷、汞的含量

用硝酸-过氧化氢溶液(3+3)作为消解剂,微波消解法处理木薯淀粉等样品,采用电感耦合等离子体质谱法,选择适合的同位素元素,运用碰撞池技术(CCT)降低元素Cu、As的多原子离子干扰,测定样品溶液中Pb、Cu、Cd、As、Hg等元素的含量,各元素线性相关系数为0.9997 ～0.9999,元素的检出限(3sd)分别为pb...     

基于AutoCAD与VB的焊接CCT图形制作与应用

将CAD技术和焊接技术相结合．研制开发了基于AutoCAD与VB的焊接CCT图形调用系统．首先将焊接CCT图形在AutoCAD平台下制作成图形块，然后通过两种方法实现其调用，第一对AutoCAD下拉菜单进行定制后直接调用；第二应用AutoCAD的ActiveX Automation技术通过Visual Basic 6．0进行调用．并将焊接CCT有关数据制作成数据库．通过调用组织图可以预测焊缝组织．调用性能图可以预测焊缝的力学性能．并且可以实现对数据库的动态添加、生成并打印报表．系统的实现充分运用了计算机快速绘图、超大容量信息存储功能，实现了无纸化信息传输．有利于焊接CCT图的推广和应用．     

甲基丙烯酸甲酯,甲基丙烯酸与分子氧的初始氧化反应

本文研究了甲基丙烯酸及其甲酯与分子氧Ｏ２的初始氧化反应?随着通Ｏ２后密封放置时间的增加，ＭＭＡ中所生成的氢过氧化物浓度逐渐增加。而ＭＡＡ中却无变化。     

聚丙烯酸甲酯及其模型化合物与O2的初始暗氧化反应

烯酸甲酯及其模型化合物２－甲丁酸甲酯与Ｏ２能够形成不稳定的接触电荷转移复合物。在无光照条件下，通Ｏ２放置一段时间以后再通Ｎ２，ＣＣＴ吸收峰不再完全消失，其残留峰的强度随存放时间的延长，温度的升高而增加，而形和峰位与原ＣＣＴ相似。     

聚环氧丙烷与氧的接触电荷转移复合物及其暗氧化降解

聚醚已被广泛应用于聚合物及生物材料的制备和改性，如聚乙二醇（ＰＥＧ）已在生物、医学等许多领域获得应用［１］．但是聚醚容易被氧化，并导致分子量降低，因此影响由它制备的聚合物的性能［２］．人们对聚醚的光氧化及氧化降解已有许多报道［３，４］，然而缺少对聚醚...     

量子点网点导光板的制备及性能研究

为了实现量子点背光源的白平衡,将红量子点和绿量子点与油墨均匀混合,采用丝网印刷的工艺将混合后的量子点浆料印刷到导光板的下表面,作为导光板的网点,在侧边蓝光LED激发下,使红、绿量子点发光并和蓝光共同复合发光。通过调整优化量子点在混合浆料中的比例和红、绿量子点的配比最终实现白平衡。利用OLYMPUS显微镜、F-4600荧光分光光度计和SRC-200M光谱彩色亮度计对量子点网点导光板表面形貌和光学性能进行了表征和分析。实验结果表明:当量子点在混合浆料中的质量分数为7%并且红量子点和绿量子点满足1∶12时,能够实现白平衡,CIE 1931色坐标为(0.330 8,0.327 1),色温为5 588 K,在100 m A的激发电流下亮度可达4.136×10~3cd/m~2,色域为NTSC的122.4%。