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981.
Zhiyun Zhang Chonggao Bao Wenjing YaoShengqiang Ma Lili ZhangShuzeng Hou 《Superlattices and Microstructures》2011
Al-doped ZnO (AZO) transparent conducting films were successfully prepared on glass substrates by RF magnetron sputtering method under different substrate temperatures. The microstructural, electrical and optical properties of AZO films were investigated in a wide temperature range from room temperature up to 350 °C by X-ray Diffraction (XRD), Field-Emission Scanning Electron Microscopy (FESEM), High-Resolution Transmission Electron Microscopy (HRTEM), Hall measurement, and UV–visible meter. The nature of AZO films is polycrystalline thin films with hexagonal wurtzite structure and a preferred orientation along c-axis. The crystallinity and surface morphologies of the films are strongly dependent on the growth temperature, which in turn exerts a great effect on microstructural, electrical and optical properties of the AZO films. The atomic arrangement of AZO film having an wurtzite structure was indeed identified by the HRTEM as well as the Selected Area Electron Diffraction (SAED). The defect density of AZO film was investigated by HRTEM. The film deposited at 100 °C exhibited the relatively well crystallinity and the lowest resistivity of 3.6 × 10−4 Ω cm. The average transmission of AZO films in the visible range is all over 85%. More importantly, the low-resistance and high-transmittance AZO film was also prepared at a low temperature of 100 °C. 相似文献
982.
Abstract
The photoinduced electron transfer from chlorophyll a through the interface of positively charged dioctadecyltrimethylammonium chloride (DODAC), neutral dipalmitoylphosphatidylcholine (DPPC) and negatively charged dihexadecylphosphate (DHP) headgroup of the lipid bilayers was studied. The photoinduced radicals were identified by electron spin resonance (ESR) and radical yields of chlorophyll a were determined by double integration of the ESR spectra. The formation of vesicles was identified indirectly by measuring change of the λ max value of optical absorption spectrophotometer from diethyl ether solution to vesicle solutions, and observed directly with scanning and transmission electron microscopic images. The interaction distance between chlorophyll a and interface water (D2O) determined by deuterium modulation depth with electron spin echo modulation (ESEM) showed a decreasing order DODAC > DPPC > DHP. The interface charge of each vesicle was determined with zeta potential measurement. The interface charge of the lipid bilayers affected the radical yields of chlorophyll a more critically than the interaction distance between chlorophyll a and interface water. 相似文献983.
针对红外偏振成像系统,运用等效介质理论,在氟化钙基底上设计了周期为200 nm,深度为100 nm的金属铝栅.模拟计算结果表明,设计的金属铝栅在中红外(3—5 μm)和远红外(8—12 μm)双波段范围内,以及±20°的视场范围内能够提供大于35dB的消光比.利用电子束曝光、反应离子束刻蚀、等离子去胶等工艺完成了金属铝栅的制作.将金属铝栅放在中波红外热像仪前,得到了目标轮廓清晰的偏振图像.
关键词:
亚波长衍射光栅
偏振成像
等效介质理论 相似文献
984.
Gaass M Hüttel AK Kang K Weymann I von Delft J Strunk Ch 《Physical review letters》2011,107(17):176808
We investigate quantum dots in clean single-wall carbon nanotubes with ferromagnetic PdNi-leads in the Kondo regime. Most of the Kondo resonances exhibit a splitting, which depends on the tunnel coupling to the leads and an external magnetic field B, but only weakly on the gate voltage. Using numerical renormalization group calculations, we demonstrate that all salient features of the data can be understood using a simple model for the magnetic properties of the leads. The magnetoconductance at zero bias and low temperature depends in a universal way on gμ(B)(B-B(c))/k(B)T(K), where T(K) is the Kondo temperature and B(c) the external field compensating the splitting. 相似文献
985.
The physics behind the spin (polarization)-dependent electromagnetic hot-spot phenomenon is due to the presence of the geometric phase resulting from the optical spin-orbit interaction in the interaction of light with the subwavelength microstructures. Unlike the tiny spin-dependent shift of light associated with the usual spin-Hall effect of light, here we present the distinct polarization-dependent angular shift by employing an array of subwavelength metallic apertures. More importantly, this novel electromagnetic precession is accompanied by the extraordinary optical transmission phenomenon and offers the exciting possibilities for novel applications for subwavelength structured metallic systems. 相似文献
986.
Deok Yeon LeeMi-Sun Lee Iseul LimSoon Hyung Kang Yoon-Chae NahWonjoo Lee Sung-Hwan Han 《Applied Surface Science》2011,257(23):9879-9884
Triruthenium carbonyl clusters {[Ru3(Br)(CO)11]− (denoted as Ru-1), [Ru3(μ2-Br)(CO)10]− (denoted as Ru-2), and [Ru3(μ3-NPh)(Br)(CO)9]− (denoted as Ru-3)} were synthesized on di(3-aminopropyl)viologen (DAPV)/indium tin oxide (ITO) using a surface reaction in a ruthenium (III) carbonyl [Ru3(CO)12] solution, and were applied to photoelectrochemical cells (PECs) at the molecular level. The formation of DAPV on ITO was realized in the form of self-assembled monolayers. Ru3(CO)12 then easily reacted with the Br− of DAPV, and a mixture of Ru-1 and Ru-2 was formed on DAPV/ITO. Furthermore, Ru-3 was successfully anchored on DAPV/ITO by adding nitrosobenzene in order to react with Ru-2 on DAPV/ITO. The photocurrents of (Ru-1 and Ru-2)/DAPV/ITO and Ru-3/DAPV/ITO in PECs at the molecular level were 6.3 nA cm−2 and 8.6 nA cm−2, respectively. The quantum yield of Ru-3/DAPV/ITO was ∼0.8%. Time-resolved photoluminescence spectroscopy and emission spectroscopy were recorded to bring out the photoinduced charge transfer process from ruthenium clusters to DAPV. 相似文献
987.
Jihui Lang Xue Li Jinghai Yang Lili Yang Yongjun Zhang Yongsheng YanQiang Han Maobin Wei Ming Gao Xiaoyan Liu Rui Wang 《Applied Surface Science》2011,257(22):9574-9577
ZnO quantum-dot chains codoped with Eu3+ and Er3+ were synthesized by the chemical precipitation method and the codoping effects on the structures, morphologies and optical properties of the powders were briefly investigated. The X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) results indicated the Eu3+ and Er3+ were incorporated into the crystal lattice of ZnO host. Transmission electron microscope (TEM) measurements showed the sizes of the ZnO quantum dots decreased with the increase of Eu3+ and Er3+ doping concentration, and the quantum-dot chains were formed by codoping with Eu3+ and Er3+. The green emissions in the photoluminescence spectra were attributed to 4f-4f of Er3+ inner shell 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions, and the characteristic red emissions of Eu3+ ions were attributed to the 5D0 → 7F1 and 5D0 → 7F2 transitions, respectively. Moreover, the red emission of the Eu3+ ions gradually decreased with the Er3+ ions doping concentration increased, which may be due to the different energy storage centers in the powders. 相似文献
988.
Xiangman Zhang Bin Chen Weiguo Fu Zhengdong FangZhenjie Liu Weifeng LuZhengyu Shi Lili ChenTao Chen 《Applied Surface Science》2011,258(1):196-200
The use of current drug-loaded vascular scaffolds is limited in sustained drug release and stability studies in clinical and preclinical trials. We found that poly(l-glutamic acid)-b-poly(propylene oxide)-b-poly(l-glutamic acid) (PLGA-b-PPO-b-PLGA) triblock copolymers can deliver multiple poorly water-soluble drugs (e.g., Paclitaxel) at clinically relevant doses. In this study, we synthesized a new drug-loaded vascular external graft with electrospun nanofibrous scaffolds [poly(l-lactide-co-?-caprolactone) (PLCL):fibrinogen; 2:1 (w/w)] and drug-loaded PLGA-b-PPO-b-PLGA micelles. Cell proliferation and viability assay results showed that beagle smooth muscle cells grew well on the surface of vascular graft-coated micelles at a percentages of 10% (w/w) GPG:PLCL-fibrinogen. This study demonstrates that micelle-coated electrospun PLCL-fibrinogen vascular scaffolds have potential applications in vascular tissue engineering. 相似文献
989.
Xiangqing LiLifang Liu Shi-Zhao Kang Jin MuGuodong Li 《Applied Surface Science》2011,257(14):5950-5956
In order to study the effects of anchoring modes on the properties of porphyrin zinc (ZnP) coupled titanate nanotubes (TNTs), the TNTs coupled with 5,10,15,20-tetraphenylporphyrin zinc (ZnTPP) and 5-(4-hydroxyphenyl)10,15,20-triphenylporphyrin zinc (ZnMOHPP), which were denoted as TNTs-ZnTPP and TNTs-ZnMOHPP, were prepared using a simple refluxing method, respectively. Based on the different experimental phenomena observed during the synthesis process as well as the results of the spectral characterization, thermogravimetric analysis, photocatalysis test and photoelectrochemistry measurement, it was demonstrated that the ZnMOHPP molecules were bonded mainly on the outer surfaces of the TNTs through hydrogen bonds, while the ZnTPP molecules were physically adsorbed into the pore channels of the TNTs via a capillary process. The different anchoring modes of ZnP on the TNTs as well as the special morphology of TNTs resulted in the remarkable distinctions in the thermal stability, photocatalytic and photoelectrochemical properties. 相似文献
990.