含聚苯胺粒子的电流变液及其性能

研究了分散介质、电场种类、表面活性剂以及工作温度和时间对含聚苯胺（ＰＡｎ）粒子的电流变（ＥＲ）液性能的影响。研究发现，以氯化石腊为分散介质的ＰＡｎ的ＥＲ液的屈服应力（τｓ）最大；ＥＲ液在直流电场比在有效值相同的交流电场作用下产生的τｓ大，电流密度（ｉ）小；随表面活性剂用量的增加，ＥＲ液的τｓ出现最大值，而ｉ和零场屈服应力单调降低。结果表明，无水的ＰＡｎ的ＥＲ液具有高的ＥＲ活性、宽的工作温度区间、低     

Fabrication and characteristics of porous germanium films

Porous germanium films with good adhesion to the substrate were produced by annealing GeO₂ ceramic films in H₂ atmosphere. The reduction of GeO₂ started at the top of a film and resulted in a Ge layer with a highly porous surface. TEM and Raman measurements reveal small Ge crystallites at the top layer and a higher degree of crystallinity at the bottom part of the Ge film; visible photoluminescence was detected from the small crystallites. Porous Ge films exhibit high density of holes (10²⁰ cm⁻³) and a maximum of Hall mobility at ∼225 K. Their p-type conductivity is dominated by the defect scattering mechanism.     

Application of photoelectrochemical methods for the characterization of Cu(I) oxide layers modified in the presence of corrosion inhibitors

The influence of azole-type corrosion inhibitors (benzotriazole, mercaptobenzothiazole or mercaptobenzoxazole) on the photoelectrochemical behaviour of copper electrodes under open-circuit potential was investigated in a 0.5 M NaCl solution. A correlation between the inhibition efficiency of an inhibitor, the oxide layer thickness, the polarization resistance and the semiconducting properties of the Cu₂O layer more or less stabilized by the inhibitor was proposed. It appeared that a protective oxide layer is characterized by simultaneous p and n-type conductivities, and by a decrease of the photocurrent in the cathodic range, with increasing immersion time.     

Impedance Spectroscopy of Ion Beam Mixed Cu/BaTiO_3PTCR Ceramics

The positive temperature coefficient resistance ( PTCR) barium titanate ceramic samples have been prepared by the standard solid-state reaction method, and the ceramic samples have been treated by depositing copper films with magnetron sputtering method. The metallic copper films deposited on the ceramic substrates have been mixed at room temperature with argon ions in energy of 400 keV. Ion beam mixing induced modification of PTCR behavior of the ceramics was studied by using the ac complex impedance method and the resistance vs. temperature measurements . The results showed that room temperature resistance dramatically decreased and Curie point shifted toward higher temperature side for the ion beam mixed samples.     

用正电子湮没谱研究半导化掺杂的ZnO压敏陶瓷

用正电子湮没技术研究了半导化掺杂的ZnO压敏陶瓷,发现在配方配方ZnO-Bi2O3-TiO2-Co2O3-MnO2中掺杂半导化添加剂Z、ZN、ZCr和ZT后,商谱谱峰依次降低;正电子寿命依次增加。其中掺杂ZT的样品三电性能参数比较理想,分别为E1mA=17V/mm,α=18,IL=37。     

Photoluminescence Intermittency from Single Quantum Dots to Organic Molecules: Emerging Themes

Recent experimental and theoretical studies of photoluminescence intermittency (PI) or “blinking” exhibited by single core/shell quantum dots and single organic luminophores are reviewed. For quantum dots, a discussion of early models describing the origin of PI in these materials and recent challenges to these models are presented. For organic luminophores the role of electron transfer, proton transfer and other photophysical processes in PI are discussed. Finally, new experimental and data analysis methods are outlined that promise to be instrumental in future discoveries regarding the origin(s) of PI exhibited by single emitters.     

Ta~（5＋）掺杂的SrTiO_3系复合功能陶瓷的半导化和晶界层的研究

采用一次烧成法制备了Ｔａ５＋掺杂的ＳｒＴｉＯ３系复合功能陶瓷，测试了样品的介电性能，分析了晶粒的半导化机理，并讨论了晶界层对样品复合功能效应的影响。