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891.
We study the entanglement dynamics for a double Jaynes-Cummings model where two entangled atoms A and B locally interact with independent cavities a and b, respectively, but there are no interactions between locations Aa and Bb. We point out that there exists a parameter range in which simultaneous pairwise entanglement sudden death (ESD) for remote parties, i.e. AB, ab, Ab and Ba, may occur. We show that during this simultaneous ESD period various multipartite entanglement can be created. Our results imply that the pairwise entanglement between two independent locations may be transferred into other multipartite forms which account for the correlations between the two independent locations.  相似文献   
892.
Randomly oriented ZnO microsheets were successfully self-assembled on TiO2 nanoparticle (TN) film to act as the scattering layer via a cathodic electrodeposition process. The light scattering properties of ZnO microsheets were studied by UV-Vis spectrometer in the 400–800 nm wavelength range. It was found that ZnO microsheets exhibited excellent ability to scatter the incident light for ZnO microsheet-TiO2 nanoparticle (ZT) composite films. The results showed that dye-sensitized solar cells (DSSCs) fabricated with ZT composite films showed higher short-circuit density (Jsc) and conversion efficiency than TN-based DSSCs, due to the light scattering properties of ZnO microsheets.  相似文献   
893.
The calcifying phytoplankton species,coccolithophores,have their calcified coccoliths around the cells,however,their physio-logical roles are still unknown.Here,we hypothesized that the coccoliths may play a certain role in reducing solar UV radiation(UVR,280-400 nm) and protect the cells from being harmed.Cells of Emiliania huxleyi with different thicknesses of the cocco-liths were obtained by culturing them at different levels of dissolved inorganic carbon and their photophysiological responses to UVR wer...  相似文献   
894.
Based on the recent research progress in fractal super fibers,the growth kinematics(or pattern kinematics) of(6+1) -circle fractal super fiber with snowflake-like cross section(abbreviated asfractal super snowflake) is explored.The following results are obtained.(1) The fractal super snowflake obeys simply the straight-line growth mode.(2) At a given movement,the growth speed of the snowflake distributes uniformly in space.At a given point in space,the growth speed decreases along with the time.(3) The grow...  相似文献   
895.
In order to examine the effect of EGF1 peptides in directing nanoparticles to thrombi, the synthesized EGF1 peptide was conjugated to poly (ethyleneglycol)-poly (lactide) (PEG-PLA) nanoparticles (NP) to form EGF1-NP. A lipophilic fluorescent dye, coumarin-6, was incorporated into EGF1-NP so as to detect its loading and release capacity. The binding ability of EGF1-NP with TF-expressing cells was shown to be significantly higher than that of the non-conjugated NP. Following an intravenous administration, fluorescence was distributed along the vessel wall of the thrombosis regions in the model rats injected with coumarin-6-loaded EGF1-NP. The in vitro and in vivo results suggest that EGF1-NP is a promising drug delivery system for targeting cerebral thrombi.  相似文献   
896.
Effects of typhoon Matsa on ionospheric TEC   总被引:3,自引:0,他引:3  
The effects of typhoon Matsa on the ionosphere are studied by using GPS-TEC data observed at about 50 GPS stations.It is shown that the ionosphere has been already influenced and TEC tends to increase before the landing of Matsa,and the difference of TEC from its monthly median over the typhoon area is about 5 TECU.With the landing of Matsa,both the magnitude and the area of increased TEC decrease.One day after the landing of Matsa,TEC reaches its minimum and is lower than the monthly median.In comparison o...  相似文献   
897.
Progress on gecko-inspired micro/nano-adhesion arrays   总被引:2,自引:0,他引:2  
Gecko’s excellent adhesion ability is thought to derive from van der Waals force generated between the millions of keratinous hairs/setae and the contact surface. Fabricating highly gecko-inspired foot-hair becomes one of the key technologies to realize the three-dimensional-obstacle-free motion of robot. Researchers have fabricated various gecko-like foot-hair arrays which have leaning, large end, and hierarchical structures. Those significant works are summarized and suggestions for future work are proposed in this paper.  相似文献   
898.
U-Pb dating was made by the LA-ICP-MS method for detrital zircons from the Wudangshan volcanic-sedimentary succession in the South Qinling. Samples comprise quartz sandstones of the Wudangshan Group collected from the base of the Yangping Formation and an upper layer of the Shuangtai Formation overlain its volcanic sequence, and two river-sand collections from the drainage systems cutting across the two formations, respectively. The results show that the Yangping detrital zircons are dominated by 830–780 Ma grains with a minor population of ~1.0–0.84 Ga and sporadic grains of ~2.6, ~2.4 and 2.0 Ga, whereas the Shuangtai zircons yield an upper intercept age of 763±33 Ma, identical to the timing of the Wudangshan volcanism within error, with few concordant grains of 1.9 and 0.86 Ga. Age spectra for the two river-sand samples are similar to those of the Yangping and Shuangtai Formations, respectively. It thus suggests that the Wudangshan strata are less than 780 Ma, whereas their major detrital zircon populations of 1.0–0.85 Ga and 830–780 Ma are consistent with timing of the Hannan magmatic activities along the northwestern margin of the South China Block. This suggests a Hannan or adjacent area provenance for the Wudangshan strata. The Wudang area is characterized by rift-related igneous events at ~755 and ~680 Ma, respectively, pointing to a tectono- magmatic history different from the Hannan area. It is inferred that the ~755 Ma magmatism is likely to indicate a separation of the South China Block from the supercontinent Rodinia, while the ~680 Ma event suggests a further split between the South Qinling and some unknown continent.  相似文献   
899.
Leaf senescence as an active process is essential for plant survival and reproduction. However, premature senility is harmful to agricultural production. In this study, a rice mutant, named as psl3 (presescing leaf 3) isolated from EMS-treated Jinhui 10, displays obvious premature senility features both in morphological and physiological level. Genetic analysis showed that mutant trait was controlled by a single dominant gene (PSL3), which was located on rice chromosome 7 between SSR marker c7sr1 and InDel marker ID10 with an interval of 53.5 kb. The result may be useful for the isolation of the PSL3 gene.  相似文献   
900.
The influences of a tidal cycle on the distribution of autotrophic plankton were investigated in a hyper-eutrophic lagoon designated as a scenic area. Results showed that the highest concentrations of picoplankton and phytoplankton were found in the middle and inner part of the lagoon, irrespective of the tides. The MDS result also revealed that phytoplankton communities, dominated by Ceratium furca, were similar among stations in the inner bay during both flood tides and ebb tides. The time series sampling results at the inlet-outlet channel revealed that almost the same amounts of phytoplankton and picoplankton were carried through the channel during flood and ebb tides, with no trend in nutrient fluctuations except for phosphate which had a net loss from the lagoon. The results showed that tidal cycles do not effectively flush away phytoplankton and picoplankton from the lagoon, and the blooming of phyto- and picoplankton is inevitable should the situation stay the same. Steps are needed to alleviate the eutrophication condition instead of depending on the natural process such as tidal cycle.  相似文献   
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