溴的类镁离子跃迁谱线和能级扩展分析

用中国原子能科学研究院HI 13串列加速器提供的 90和 130MeV的Br离子和束箔技术 ,研究了波长在 13— 2 9nm范围内Br的类Mg离子的光谱 .识别出 2 4条属于BrXXIV的“3,3”跃迁 ,即 3s2 ,3s3p ,3p2 ,3s3d和 3p3d组态之间的跃迁谱线 ,其中 19条以前未见报道 .基于实验跃迁谱线 ,19个观测能级得以确立 ,其中有 14个能级此前未见报道 .相对论Hartree Fock(HFR)方法的计算结果对所观测的能级进行了解释.The spectrum of Mg-like Br, Br XXIV is investigated by means of beam-foil technique. Bromine ions of 90 and 130 MeV energy from the HI-13 tandem accelerator are used, and the wavelength region 13-29 nm is investigated. In the spectra, 24 Br XXIV transitions within the n=3 complex, i.e. between the 3s 2, 3s3p, 3p 2, 3s3d and 3p3d configurations are identifies, among them 19 have not been reported before. Based on these transition lines 19 energy levels have been determined and 14 energy level...     

碱性离子液体水解-双水相胶束体系提取-超高效液相色谱法测定水产品中胆固醇的含量

基于碱性离子液体水解以及双水相胶束体系(ATPMS)提取,以超高效液相色谱法(UHPLC)测定水产品中胆固醇的含量,并以分配系数为指标对ATPMS组成进行了优化.称取0.10 g肉糜状水产品,加入0.36 mol·L-1氢氧化1-丁基-3-甲基咪唑盐([C4 mim]OH)碱性离子液体1 mL,于90℃加热30 min...     

利用皮秒激光激发技术研究纳米硫增感溴化银中光电子特性

纳米硫增感作为一种新型的增感手段,能很大程度上提高卤化银感光材料的性能.卤化银中光电子信号十分微弱,光电子寿命在纳秒量级,本文采用微弱信号的微波吸收相敏检测技术,它能精确地测量载流子的时间特性,反映感光过程的细微变化.通过测量我们获得了不同纳米硫化物粒子增感的立方体溴化银乳剂中光电子的瞬态行为,分析了不同增感温度对增感的溴化银乳剂中光生电子随增感时间而衰减的影响.结果表明:当增感温度增加时,可以缩短乳剂达到最佳光电子利用率的增感时间.     

辉光放电等离子体处理阳离子染料结晶紫废水

用辉光放电等离子体技术对结晶紫进行了降解脱色处理,考察了多种因素对结晶紫降解效果的影响。实验发现,提高电解质浓度和增加电压均可提高结晶紫的脱色效果,考虑到电极损耗,辉光放电最佳条件为:电解质浓度为2 g/L Na2SO4,电压为600 V。当改变溶液的初始pH值时,结晶紫的脱色率随溶液的初始pH值升高而增加,加入一定量H2O2能明显地提高结晶紫的脱色效率;若加入0.4 mmol/L Fe2 ,5 min时结晶紫的脱色率由原来的13.64%增加到91.36%。结果表明,辉光放电产生的.OH对结晶紫的降解起重要作用。最佳条件下,40 min内的脱色率达到93%,降解率为74%。     

甲酸和草酸盐掺杂的AgBr乳剂对亲水型PTG材料感光性能的影响

研究了甲酸盐掺杂和草酸盐掺杂对AgBr乳剂和亲水型PTG材料感光性能的影响.实验结果表明,掺杂后的AgBr乳剂在PTG材料中作为光敏元显著提高了其相对感光度,而不引起灰雾的增加;掺杂增感与硫增感、金增感、硫加金增感在PTG材料中同样表现出协同增感效果,使PTG材料的感光度得到进一步的提高;掺杂后的AgBr乳剂在PTG材料中具有一个最佳使用量,即Ag-Br与硬脂酸银的摩尔比为1:4.     

Polymer thin-film transistor based on a high dielectric constant gate insulator

In this paper full polymer thin-film transistors (PTFTs) based on Poly (acrylonitrile) (PAN) as the gate dielectric and poly (2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene-vinylene) (MEH-PPV) as the semiconductor layer were investigated by using different channel width/length ratios. Relatively high dielectric constant of the polymer dielectric layer (6.27) can remarkably reduce the threshold voltage of the transistors to below -3V. Hole field-effect mobility of MEH-PPV of the PTFTs was about 4.8×10^-4cm²/Vs, and on/off current ratio was larger than 10², which was comparable with that of transistors with widely used Poly (4-vinyl phenol) (PVP) or SiO₂ as gate dielectrics.     

Noninvasive temperature estimation by detecting echo-strain change including thermal expansion

This article studies the feasibility of noninvasive temperature estimation by detecting echo-strain including thermal expansion in therapeutic ultrasound treatment. This technique evaluates distributions of echo-strain and temperature inside the tissue by detecting echo signals pre- and post-heating, in combination with the temperature dependence of sound speed and thermal expansion. In the computer simulation and experimental study, echo signals pre- and post-heating are acquired and then the temperature elevation is evaluated by correlation analysis. Results demonstrate that this technique can effectively extend the measured temperature range up to 75$^{\circ}$C with an accuracy of $\pm $2$\,^{\circ}$C.     

化学反应速率和活化能测定微型实验初探

根据无机实验的教学实际,对化学反应速率和活化能的测定进行了微型化学实验设计,其试剂用量比对应常规实验少90%左右,测定结果达到无机化学实验对测定精度的要求.     

NuTeV反常与奇异夸克反夸克不对称性

总结了利用核子内的奇异夸克反奇异夸克不对称性来解释NuTeV反常的工作,表明奇异夸克反奇异夸克不对称性可作为解释NuTeV反常的一种合理机制,也说明了NuTeV反常现象也可能是对奇异夸克反奇异夸克不对称性的一种支持。This talk summarized the results of using strange quark-antistrage quark asymmetry of the nucleon to explain the NuTeV anomaly. It is shown that asymmetric strange quark-antistrage quark distributions may be a reasonable explanation for the NuTeV defect. On the other side, the NuTeV anomaly could be the evidence for the existence of asymmetric strange-antistrange quark distributions.     

含双蒽基团酰胺受体分子的合成及阴离子识别研究

合成了一种新型的带有双蒽基团的酰胺阴离子受体B.用荧光光谱、紫外-可见吸收光谱以及核磁共振氢谱研究了B与Cl^-,Br^-,I^-及对硝基酚氧阴离子的相互作用.结果表明,B与Cl^-,Br^-,I^-等阴离子无识别作用,而与对硝基酚氧阴离子有较好的选择性识别能力,其络合比为1∶1.利用荧光发射强度和吸光度的变化分别计算出主体B与客体相互作用的络合常数KS分别为(1.24±0.07)×10⁵和(1.27±0.18)×10⁵,并对主体分子B与客体之间的相互作用进行了讨论.