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Fullerene is a well-known carbon nanomaterial, which can be potentially used for drug manufacture or delivery. Despite several successful examples of utilizing fullerene derivatives as drug candidate materials, their low water solubility under physiological conditions negatively affects the cell penetration efficiency after treatment. In this work, we successfully synthesized two fullerene derivatives with covalently attached fluorescein and boron dipyrromethene (BODIPY) fluorophore moieties, which exhibited cellular uptake and intracellular localization. While both fluorophores decreased their fluorescence intensity in the vicinity of fullerene, the cellar uptake of the fluorescein-modified fullerene was detected via fluorescence microscopy observations. Moreover, decreases in the fluorescence intensities of the intact fluorescein and BODIPY species were observed when both fluorophores and fullerene coexisted in aqueous media.  相似文献   
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The metal-induced regulation of fullerene complexation with double-calix[5]arene is described. The receptor shows strong binding to C70 only in the presence of Cu+.  相似文献   
66.
We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence.  相似文献   
67.
High‐density polycrystalline samples (above 98% of the theoretical density) of Ag8GeTe6 were prepared by solid‐state reactions of Ag2Te, GeTe, and Te, followed by hot‐pressing. The thermoelectric properties were measured at temperatures ranging from room temperature to around 700 K. The thermal conductivity values were extremely low (0.25 Wm–1 K–1 at room temperature), and consequently Ag8GeTe6 exhibited a relatively high thermoelectric figure of merit, ZT = 0.48 at 703 K. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
68.
In order to study the role of viologen-containing vinyl polymers in light energy conversion systems, the photoreduction of the polymer by 2-propanol and the properties of the reduced polymer were studied in comparison with methylviologen. There were marked polymer effects in the initial rate of photoreduction as well as in the absorption spectra of the photoreduced species. Both effects were interpreted in terms of the local concentration effect of viologen units in the photoreduction step. The spectral difference was found to be due to the dimeric association of the reduced viologen units on the polymer.  相似文献   
69.
The extraordinary Hall resistivity rho(xy) and the magnetization M of a canonical spin glass AuFe (8 at.% Fe) were measured simultaneously as functions of temperature with the best care to the thermal and the magnetic field hysteresis. The data of rho(xy) show an anomaly at the spin glass transition temperature T(g) and have different zero field cooling (ZFC) and field cooling (FC) measurements below T(g). Moreover, the value of rho(xy)/M, which represents the chiral susceptibility of the system in the present case, also shows the difference between ZFC and FC measurements. The results are consistent with the predictions of the chirality scenario of canonical spin glasses by Kawamura.  相似文献   
70.
We present a determination of the Cabibbo-Kobayashi-Maskawa parameter |V(us)| based on new measurements of the six largest K(L) branching fractions and semileptonic form factors by the KTeV (E832) experiment at Fermilab. We find |V(us)|=0.2252+/-0.0008(KTeV)+/-0.0021(ext), where the errors are from KTeV measurements and from external sources. We also use the measured branching fractions to determine the CP violation parameter |eta(+-)|=(2.228+/-0.005(KTeV)+/-0.009(ext))x10(-3).  相似文献   
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