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991.
Huirui Zhou Ke Tao Yunqi Sui Kang Sun 《Physica E: Low-dimensional Systems and Nanostructures》2011,44(3):597-604
The heterogeneous nucleation and growth of CdSe domains on the Fe3O4 seed nanocrystals are hard to be controlled because of significant lattice mismatch between Fe3O4 and CdSe nanocrystals. Current study exploits the choice of surface ligand and crystal morphology for Fe3O4 seed to investigate ways to overcome the energy barrier imposed by the lattice mismatch for the promotion and control of subsequent growth of CdSe nanocrystals on seeded crystals. Results indicate that the growth of CdSe domains on seed nanocrystals not only depends on the affinity of ligands toward seed nanocrystals, but also is affected by the seed ligands in a similar way to synthesizing individual second-domain nanocrystals. Furthermore, preferential growth of CdSe domains on the corner of cubic seeds are observed, and cubic Fe3O4 nanocrystals are favored for the heterogeneous nucleation of CdSe as opposed to spherical ones. A three-stage growth model (heterostructures formation, the adsorption of Se and the heterogeneous nucleation and growth) is proposed, where choice of ligands, geometry features, such as surface curvature and defects are found to have significant impact to overcome energy barrier from lattice mismatch. 相似文献
992.
Motivated by the recent pioneering advances on nanoscale plasmonics and also nanophotonics technology based on the surface plasmons (SPs), in this work, we give a master equation model in the Lindblad form and investigate the quantum optical properties of single quantum dot (QD) emitter coupled to the SPs of a metallic nanowire. Our main results demonstrate the QD luminescence results of photon emission show three distinctive regimes depending on the distance between QD and metallic nanowire, which elucidates a crossover passing from being metallic dissipative for much smaller emitter-nanowire distances to surface plasmon (SP) emission for larger separations at the vicinity of plasmonic metallic nanowire. Besides, our results also indicate that, for both the resonant case and the detuning case, through measuring QD emitter luminescence spectra and second-order correlation functions, the information about the QD emitter coupling to the SPs of the dissipative metallic nanowire can be extracted. This theoretical study will serve as an introduction to understanding the nanoplasmonic imaging spectroscopy and pave a new way to realize the quantum information devices. 相似文献
993.
Luu Viet Hung O. D. Maslov M. V. Gustova Trinh Thi Thu My Phung Khac Nam Ho 《Physics of Particles and Nuclei Letters》2011,8(4):412-416
The leaves, stem, and roots of two types of shrubs (tea (Camellia sinensis) and sweet leaf (Sauropus androgynus)) and two types of herbs (vetiver grass (Vetiveria zizanioides L. Nash) and maize (Zea mays L)) and the Thucuc soil where the plants were growing were collected to be studied. The contents of 22 elements in the samples
were determined by three methods: X-Ray fluorescence analysis (XRFA), gamma activation analysis (GAA), and the tracking method
to study the distribution of these elements in plants and the soil-plant relationship. This study was carried out at the Flerov
Laboratory of Nuclear Reactions (FLNR), Joint Institute for Nuclear Research (JINR), Dubna, Russia. The distribution of the
elements in the soil-plant system was studied. 相似文献
994.
Il-Suk Kang Young-Su Kim Hyun-Sang Seo Chi Won Ahn Jun-Mo Yang Wook-Jung Hwang 《Current Applied Physics》2011,11(6):1319-1321
The effect of two-step hydrogenation, consisting of plasma hydrogenation and annealing in hydrogen, on the hysteresis phenomenon of metal-induced unilaterally crystallized silicon thin-film transistors (MIUC-Si TFTs) was investigated. The large hysteresis level of the conventional MIUC-Si TFTs caused a wide variation of the drain current with the previous gate voltage. As the plasma exposure time increased, the plasma hydrogenation commonly used for stability in poly-Si TFTs was found to increase the hysteresis level of MIUC-Si TFTs after a minimum point. This is because plasma-induced damages correlated with unique defects of MIUC-Si such as metal-related weak bonds, are accompanied by passivation. The following annealing repaired the damages. Consequently the hysteresis level was lower, which resulted in a narrower variation of the drain current. 相似文献
995.
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996.
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
997.
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
998.
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
999.
1000.
J. Glister G. Ron B.W. Lee R. Gilman A.J. Sarty S. Strauch D.W. Higinbotham E. Piasetzky K. Allada W. Armstrong J. Arrington H. Arenhövel A. Beck F. Benmokhtar B.L. Berman W. Boeglin E. Brash A. Camsonne J. Calarco J.P. Chen S. Choi E. Chudakov L. Coman B. Craver F. Cusanno J. Dumas C. Dutta R. Feuerbach A. Freyberger S. Frullani F. Garibaldi J.-O. Hansen T. Holmstrom C.E. Hyde H. Ibrahim Y. Ilieva C.W. de Jager X. Jiang M.K. Jones Hyekoo Kang A. Kelleher E. Khrosinkova E. Kuchina G. Kumbartzki J.J. LeRose R. Lindgren P. Markowitz S. May-Tal Beck E. McCullough D. Meekins 《Physics letters. [Part B]》2011