非共价键自组装制备聚对苯撑乙炔/聚丙烯酸水溶性荧光纳米粒子及其光物理行为研究

通过功能化聚对苯撑乙炔(含羟基与氨基)和聚丙烯酸之间的非共价键自组装制备了一系列含共轭聚合物的水溶性荧光纳米粒子, 并进行了相关结构和光学性质表征. 研究表明, 纳米粒子的大小和聚丙烯酸/聚对苯撑乙炔质量比直接相关. 光物理性质研究表明, 形成水溶性纳米粒子后, 疏水的聚苯撑乙炔链在纳米粒子中易于形成π-链间聚集, 其光物理性质与其在薄膜态时相似.     

一致结构的单子及其应用

讨论了乘积一致结构的单子的刻画 .利用一致结构的单子给出了 Cauchy网及含小集集族的非标准特征 .作为应用给出一致空间几个重要定理的离散化证明 .     

用介观动力学模拟Pluronic L64/水/p-Xylene体系的相分离

用介观动力学在介观层次上对不同组分的PluronicL64/水/p-xylene三元体系的相分离进行了研究,得到了和实验相吻合的结果。计算表明对于纯p-xylene溶剂和有含少量水的p-xylene溶剂,体系没有发生相分离,随着水的含量增加,体系发生了明显的相分离,产生了不同形态的胶团。本研究还通过对比不同溶剂组分下的体系介观形貌,讨论了水在体系相分离中的作用。同时通过分析模拟了1000步后体系中水的分布,证实在胶团核中存在自由水(freewater)的猜想。     

First-principles calculations for transition phase and thermodynamic properties of GaAs

The transition phase of GaAs from the zincblende (ZB) structure to the rocksalt (RS) structure is investigated by ab initio plane-wave pseudopotential density functional theory method, and the thermodynamic properties of the ZB and RS structures are obtained through the quasi-harmonic Debye model. It is found that the transition from the ZB structure to the RS structure occurs at the pressure of about 16.3\,GPa, this fact is well consistent with the experimental data and other theoretical results. The dependences of the relative volume V/V₀ on the pressure P, the Debye temperature \Th and specific heat C_V on the pressure P, as well as the specific heat C_V on the temperature T are also obtained successfully.     

罗丹明B荧光猝灭法测定水中痕量亚氯酸根

在有KI存在的乙酸钠-HCl酸性缓冲溶液中,用520 nm光激发罗丹明B(RhB),在580 nm处有一个荧光峰。当有亚氯酸根(ClO-2)存在时,罗丹明B荧光峰发生猝灭。亚氯酸根浓度在0.021 8～0.51 μg·mL-1范围内与荧光猝灭强度成线性关系,据此建立了一个简便灵敏的亚氯酸根荧光分析新方法,用于测定合成水样中(ClO-₂)的分析,结果令人满意。     

硅锆复合包覆BiVO4晶体的表征及其机理研究

利用正硅酸乙酯(TEOS)和氧氯化锆(ZrOCl2·8H2O)的水解反应并经高温煅烧后,在BiVO4晶体表面形成SiO2·ZrSiO4膜,以提高BiVO4的耐高温性.采用红外光谱仪、X射线衍射仪、差热分析仪对产品进行了表征,并得出结论:包覆SiO2·ZrSiO4膜后的BiVO4晶体,其耐热温度由680℃提高到1000℃,并对包覆机理进行了探讨.     

Finite-size effect and Kondo screening effect in an A-B ring with a quantum dot

The properties of the ground state of a closed dot－ring system with a magnetic flux in the Kondo regime are studied theoretically by means of a one-impurity Anderson Hamiltonian. The Hamiltonian is solved by means of the slave-boson mean-field theory. It is shown that at T=0, a suppressed Kondo effect exists in this system even when the mean level spacing of electrons in the ring is larger than the bulk Kondo temperature. The physical quantities depend sensitively on both the parity of the system and the size of the ring; the rich physical behaviour can be attributed to the coexistence of both the finite-size effect and the Kondo screening effect. It is also possible to detect the Kondo screening cloud by measuring the persistent current or the zero field impurity susceptibility χ_{imp} directly in future experiments.     

"引商进店"与商场--零售商的竞争和合作策略

“引商进店”是商场的新式经营策略,它通过把柜台出租给品牌零售商,从中收取租金获利.该模式目前被绝大多数的商场所采用,其本质就是零售租赁.本文在假设零售商支付给商场固定租金加分成租金的基础上,探讨了两种博弈类型下系统的均衡结果.     

CONSTRUCTING UNIFORM DESIGNS WITH TWO- OR THREE-LEVEL

When the number of runs is large, to search for uniform designs in the sense of low-discrepancy is an NP hard problem. The number of runs of most of the available uniform designs is small (≤50). In this article, the authors employ a kind of the so-called Hamming distance method to construct uniform designs with two- or three-level such that some resulting uniform designs have a large number of runs. Several infinite classes for the existence of uniform designs with the same Hamming distances between any distinct rows are also obtained simultaneously. Two measures of uniformity, the centered L2-discrepancy (CD, for short) and wrap-around L2-discrepancy (WD, for short), are employed.