过渡金属掺杂ZnO的电子结构和光学性质

利用基于密度泛涵理论的超软赝势法(USPP)，结合局域密度近似(LDA)，对过渡族金属离子掺杂的纤锌矿型ZnO做第一性原理计算，得到了它的平衡晶格常数、结合能、电子态密度分布、能带结构、介电函数、光学吸收系数等性质，详细讨论了掺杂后ZnO化合物的电子结构及成键情况，并结合实验结果定性分析了掺杂后光学性质的变化. 关键词： 氧化锌 掺杂 第一性原理 光学性质     

采用拉曼光谱技术研究纳米锐钛矿到金红石的相转变

采用化学沉淀法制备出40nm的锐钛矿，并用拉曼光谱对纳米和块体锐钛矿到金红石的相转变过程进行了研究。实验结果表明：对于块体锐钛矿，在950℃保温1h，金红石的特征峰446cm^-1开始出现，随着温度的升高，金红石的特征峰446，610和231cm^-1继续增强，锐钛矿的特征峰639，515和397cm^-1逐渐减弱。在1100℃保温1h，锐钛矿转变为金红石；对于纳米锐钛矿，在900℃保温1h后几乎全部转变为金红石，比块体（微米级）锐钛矿到金红石的相转变温度降低了200℃。     

+3价离子掺杂钨酸铅晶体发光性能和微观缺陷的研究

通过透射光谱、x射线激发发射光谱（XSL）的测试，研究了Bridgman法生长的几种不同+3价离子掺杂钨酸铅晶体的发光性能，并利用正电子湮没寿命谱（PAT）和x光电子能谱（XPS）的实验手段，对不同钨酸铅晶体的微观缺陷进行研究.实验表明，不同的+3价离子掺杂，对钨酸铅晶体发光性能的改善不同，并使得晶体中正电子俘获中心和低价氧的浓度发生不同变化.其中掺镧晶体的正电子俘获中心和低价氧浓度均上升，而掺钇和掺铋晶体的正电子俘获中心和低价氧浓度均下降，掺锑晶体则出现了正电子俘获中心浓度上升、低价氧浓度下降的情况.提 关键词： 钨酸铅晶体 +3价离子掺杂 正电子湮没寿命谱 x光电子能谱     

利用Gupta势结合遗传算法研究ConCu55－n(n=0—55)混合团簇的结构演化及基态能量

采用半经验的Gupta多体势结合遗传算法对Co_nCu_55－n(n=0—55)混合团簇的基态结构和能量进行了研究,发现这些混合团簇的基态结构是在Co₅₅,Cu₅₅单质团簇(Mackay二十面体)的基础之上发生的畸变;从n=0(Cu₅₅)开始,Co原子从中心到表面,从棱到顶点依次、连续替换Cu原子;基态结构与键能较大键的数目及其平均键长有关;Co₁₃Cu₄₂具有最稳定的结构,13个Co原子全部位于团簇内部形成Mackay二十面体对整个团簇的稳定性有显著影响. 关键词： 团簇 结构和能量 Gupta势 遗传算法     

高压下制备的累托石/酚醛树脂复合材料微结构和热性能研究

 采用物理方法在高压下制备了酚醛树脂（PF）/累托石（REC）纳米复合材料,用X射线衍射（XRD）、透射电子显微镜（TEM）及热分析（DSC/TGA）等方法,研究了复合材料的物相、显微结构以及热学性能。结果表明,不通过层间高分子聚合反应,不预先对累托石进行有机化处理,在高压下,由聚合物分子插入粘土层间,可以形成剥离型树脂/粘土纳米复合材料,并且其热学性能发生了较大的改变。     

Thermo-Responsive ZnPc-g-TiO2-g-PNIPAM Photocatalysts Sensitized with Phthalocyanines for Water Purification under Visible Light

A novel thermo-responsive 2,9(10),16(17),23(24)-tetrakis[(3-carboxyacrylamide) phthalocyaninato] zinc (ZnPc)-g-TiO₂-g-poly(N-isopropylacrylamide) (PNIPAM) photocatalyst modified with phthalocyanines was prepared. The photocatalyst exhibited thermo-responsive properties due to the introduction of PNIPAM, which performed recovery for reuse above the lower critical solution temperature (LCST, about 26 °C). ZnPc-g-TiO₂-g-PNIPAM effectively expanded the light response range to the visible light region and inhibited the recombination of electron–hole pairs, which enhanced the performance of the photocatalyst. As expected, ZnPc-g-TiO₂-g-PNIPAM (0.3 g/L) exhibited excellent photocatalytic performance for the removal of Rhodamine B (RhB, 1.0 × 10⁻⁵ mol/L) and methylene blue (MB, 1.0 × 10⁻⁵ mol/L) under visible light, which reached 97.2% and 88.6% at 20 °C within 40 min, respectively. Furthermore, the influence of temperature upon photocatalytic performance was also investigated. When the temperature increased from 20 °C to 45 °C, the removal of RhB decreased by approximately 53.8%. The stability of the photocatalyst demonstrated that the photocatalytic activity was still above 80% for the removal of RhB after 3 cycles. Above all, this work provided an intelligent thermally responsive photocatalyst based on phthalocyanine for water purification under visible light.     

Suppression of Phase and Amplitude Damping Decoherence in a Three-Level Atom in A-Configuration Using Bang-Bang Controls

In this paper, we present decoupling bang-bang operations for the suppression of general decoherence, both amplitude and phase damping, in a three-level system in A-configuration. We give a program to design a sequence of periodic twinborn pulses to suppress the decoherence in such the system.     

Theoretical Investigating Mechanisms of Drug-Resistance Generated by Mutation-Induced Changes in Influenza Viruses

Influenza A (A/H\begin{document}$ x $\end{document}N\begin{document}$ y $\end{document}) is a significant public health concern due to its high infectiousness and mortality. Neuraminidase, which interacts with sialic acid (SIA) in host cells, has become an essential target since its highly conserved catalytic center structure, while resistance mutations have already generated. Here, a detailed investigation of the drug resistance mechanism caused by mutations was performed for subtype N9 (A/H7N9). Molecular dynamics simulation and alanine-scanning-interaction-entropy method (ASIE) were used to explore the critical differences between N9 and Zanamivir (ZMR) before and after R294K mutation. The results showed that the mutation caused the hydrogen bond between Arg294 and ZMR to break, then the hydrogen bonding network was disrupted, leading to weakened binding ability and resistance. While in wild type (A/H7N9\begin{document}$ ^{ \rm{WT}} $\end{document}), this hydrogen bond was initially stable. Meanwhile, N9 derived from A/H11N9 was obtained as an R292K mutation. Then the relative binding free energy of N9 with five inhibitors (SIA, DAN, ZMR, G28, and G39) was predicted, basically consistent with experimental values, indicating that the calculated results were reliable by ASIE. In addition, Arg292 and Tyr406 were hot spots in the A/H11N9\begin{document}$ ^{ \rm{WT}} $\end{document}-drugs. However, Lys292 was not observed as a favorable contributing residue in A/H11N9\begin{document}$ ^{ \rm{R292K}} $\end{document}, which may promote resistance. In comparison, Tyr406 remained the hotspot feature when SIA, ZMR, and G28 binding to A/H11N9\begin{document}$ ^{ \rm{R292K}} $\end{document}. Combining the two groups, we speculate that the resistance was mainly caused by the disruption of the hydrogen bonding network and the transformation of hotspots. This study could guide novel drug delivery of drug-resistant mutations in the treatment of A/H\begin{document}$ x $\end{document}N9.     

气相色谱与串联质谱联用检测血清中脱氢表雄酮

在晚期前列腺癌雄激素全阻断治疗最终导致前列腺癌雄激素非依赖性的转变过程中,肾上腺分泌脱氢表雄酮(DHEA)被认为是重要的诱因。本研究主要利用睾丸摘除(去势)大鼠模型,对血清中DHEA浓度进行测定。采用了气相色谱与串联质谱联用(GC-MS/MS)技术,建立了高灵敏度的测定大鼠血清中脱氢表雄酮(DHEA)的方法。样品经过甲醇沉蛋白,而后固相萃取提取血清中微量的DHEA,通过七氟丁酸酐(HF-BA)衍生,采用GC-MS/MS测定。对固相萃取条件、衍生化条件以及质谱测定条件进行优化。DHEA在0.1~100μg/L范围内线性良好,相关系数r为0.9996;在2~50μg/L浓度范围内,加标回收率在99%~106%之间;相对标准偏差小于5%。本方法灵敏度高,选择性好,可满足临床对于血清样品中DHEA的测定要求。对去势大鼠血清中DHEA测定结果表明,去势后DHEA明显上升。     

金属氧化物在蛋白质组学研究中的应用

本文对近年来金属氧化物在蛋白质组学研究中发挥的作用进行了综述。重点介绍了该类化合物在蛋白质样品富集、固定化酶反应器、生物传感器和生物移植材料等方面的应用,并展望了其在蛋白质组学研究中的发展前景。