实验室安全环保意识的调查与分析——以中山大学化学类专业学生为例

A survey about students' laboratory safety and environmental protection consciousness was performed in the freshmen majored in chemistry at Sun Yat-Sen University. Results showed that laboratory safety and environmental protection consciousness of most students' are weak. After analyzing the reasons, we put forward some suggestions. Cultivating students' laboratory safety and environmental protection consciousness should be carried out from several aspects such as emphasizing and regulating from school level, training in laboratory teaching, maintaining good cultural atmosphere of laboratory, as well as providing perfect laboratory safety and environmental protection facilities. We should guide students to actively learn knowledge and skills of laboratory safety and environmental protection in order to develop their good behavior and raise their consciousness.     

火焰原子吸收光谱法测定饲料级硫酸盐中的铜

建立了火焰原子吸收光谱法测定饲料级硫酸盐中铜的方法,讨论了共存离子的干扰情况.在最佳实验条件下,该方法测定铜的特征浓度为0.019μg/mL,相对标准偏差为0.24％,样品加标回收率为99.2％-105.6％.被分析的饲料级硫酸盐中的共存离子对铜的测定基本无干扰.方法简便、快速,具有较高的准确度和精密度,适合用于饲料级硫酸盐中微量铜的测定.     

纳米金/β-环糊精复合修饰碳糊电极测定亚硝酸盐

本文研究了亚硝酸盐(NO_2~-)在纳米金和β-环糊精复合修饰碳糊电极(AuNPs-β-CD/CPE)上的电化学行为。实验结果表明,与裸CPE相比,AuNPs-β-CD/CPE对NO_2~-的电化学氧化有显著的促进作用,其氧化峰电流显著增加。同时用循环伏安法(CV)、计时电流法(CA)测定了NO_2~-在AuNPs-β-CD/CPE上的电极反应动力学参数,用线性扫描伏安法(LSV)法测得NO_2~-氧化峰电流与其浓度在6.0×10-6~8.0×10-3 mol·L-1范围内呈良好的线性关系,检出限(S/N=3)为5.7×10-7 mol·L-1。将该传感器应用于水样的检测,相对标准偏差在0.15%~1.40%之间,回收率达99.3%~104.0%,检测结果符合定量测定要求。     

铈基催化剂催化氧化燃煤烟气中汞的实验及机理研究

采用超声波增强的浸渍法合成了CeO₂-TiO₂催化剂,并采用BET,XRD,XPS等分析手段对催化剂进行了表征。利用固定床反应器,在模拟燃煤烟气条件下研究了CeO₂-TiO₂催化剂对单质汞的催化氧化行为及机理。结果表明:CeO₂-TiO₂催化剂在低温范围（150～250°）具有很强的催化氧化汞的能力;最佳的CeO₂/TiO₂质量比在1.5左右,此时汞的氧化效率可高达90%以上;P25,Evonik TiO₂比锐钛矿TiO₂更适合做铈基催化剂载体;CeO₂-TiO₂催化剂上汞的催化氧化符合Langmuir-Hinshelwood机理,即吸附态的汞与其邻近的活性物质反应生成氧化态汞。     

含参广义集值强向量平衡问题的稳定性

本文借助集合极限的性质和弱f-性假设证明了含参广义集值强向量平衡问题解集映射的下半连续性,其方法不同于最近文献(Zhao,2016和Meng,2018).此外,建立了含参广义集值强向量平衡问题解集连通性的充分条件,并举例验证了所得结果的正确性.本文得结果推广和改进了已有文献(Gong,2008,Xu,2009,Chen,2010,Xu,2013和Zhao,2013)中相应结果.     

Research Progress and Application of Ion Funnel Technique

Ion funnel is a new-style ion guider which can reduce spatial divergence and energy dispersity of the transmission ions by using radio frequency (RF) electric field to confine the ions radially and the direct current (DC) axial electric field to move the ions toward the exit, and thus it can greatly increase the ion transmission efficiency and improve the sensitivity of the mass spectrometry. Since ion funnel was invented in 1997, it has attracted a close attention of mass spectrometry scientists all over the world. Ion funnel has been used in various kinds of mass spectrometry, and built a bridge with high efficiency ion transmission between low vacuum ionization source and high vacuum mass analyzer. In this paper, the principle, technology development, and application progress of ion funnel are reviewed, and the future prospects are prospected.     

旋涂法制备WO3薄膜电致变色性能

"智能窗"大规模推广顺应可持续发展潮流,三氧化钨(WO_3)是生产"智能窗"的一种重要电致变色材料,但调控WO_3薄膜电致变色性能机制仍待进一步研究。采用旋涂法制备WO_3薄膜,重点研究了溶液浓度和旋涂次数对调控WO_3薄膜电致变色性能的影响。通过表面轮廓仪测量薄膜厚度,X射线衍射(XRD)测量薄膜结晶情况,原子力显微镜(AFM)和扫描电子显微镜(SEM)分析薄膜表面形貌,光谱仪测量薄膜初始态、着色态和褪色态的透射率。实验结果表明,随着溶液浓度增加(0. 2～1. 0 mol/L),薄膜厚度从9. 7 nm增加到33. 3 nm,透射率调制能力从0%提升到37. 0%;多次旋涂薄膜厚度线性增长,线性拟合优度(R~2)达0. 98,5次旋涂后透射率调制能力达51. 3%。改变溶液浓度和旋涂次数都是调控薄膜透射率调制能力的有效手段,精准调控薄膜透射率调制能力对设计不同应用场景的电致变色器件具有重大意义。     

Characteristics of the magnetic analysis system for a compact MPR-type spectrometer

The magnetic proton recoil(MPR)spectrometer is a novel diagnostic instrument with high perfor-mance for measurements of neutron spectra in inertial confinement fusion(ICF)experiments and high power fusion devices.A compact MPR-type spectrometer dedicated to the research of pulsed deuterium-tritium(DT)neutron spectroscopy of special experimental conditions is currently under design.Analyses of the main parameters and performance of the magnetic analysis system through 3-D particle transport calculations and MonteCarlo simulations and calibration of the system performance as a test using CR-39 solid track detector and α particle from 239pu and 226Ra radioactive sources are presented in this paper.The results indicate that the magnetic analysis system will achieve a detection efficiency level of 10-5-10-4 at an energy resolution of 1.5%-2.1%,and fulfills the design goals of the spectrometer.     

R~N上具有渐近线性项的奇异椭圆问题的研究（英文）

本文通过变分方法,证明包含Hardy位势的奇异椭圆问题-Δu(x)-μ/|x|2u(x)=K(x)f(u),x ∈RN,x在u∈D1,2(RN)中至少有一个非平凡解,其中N≥3,0≤μ≤∶=((N-2)/2)2,f(t)是在R上的连续函数并且在无穷远处渐近线性.