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81.
Tung VC Huang JH Tevis I Kim F Kim J Chu CW Stupp SI Huang J 《Journal of the American Chemical Society》2011,133(13):4940-4947
Heterojunctions between different graphitic nanostructures, including fullerenes, carbon nanotubes and graphene-based sheets, have attracted significant interest for light to electrical energy conversion. Because of their poor solubility, fabrication of such all-carbon nanocomposites typically involves covalently linking the individual constituents or the extensive surface functionalization to improve their solvent processability for mixing. However, such strategies often deteriorate or contaminate the functional carbon surfaces. Here we report that fullerenes, pristine single walled carbon nanotubes, and graphene oxide sheets can be conveniently coassembled in water to yield a stable colloidal dispersion for thin film processing. After thermal reduction of graphene oxide, a solvent-resistant photoconductive hybrid of fullerene-nanotube-graphene was obtained with on-off ratio of nearly 6 orders of magnitude. Photovoltaic devices made with the all-carbon hybrid as the active layer and an additional fullerene block layer showed unprecedented photovoltaic responses among all known all-carbon-based materials with an open circuit voltage of 0.59 V and a power conversion efficiency of 0.21%. The ease of making such surfactant-free, water-processed, carbon thin films could lead to their wide applications in organic optoelectronic devices. 相似文献
82.
Culture of cells as three-dimensional (3D) aggregates can enhance in vitro tests for basic biological research as well as for therapeutics development. Such 3D culture models, however, are often more complicated, cumbersome, and expensive than two-dimensional (2D) cultures. This paper describes a 384-well format hanging drop culture plate that makes spheroid formation, culture, and subsequent drug testing on the obtained 3D cellular constructs as straightforward to perform and adapt to existing high-throughput screening (HTS) instruments as conventional 2D cultures. Using this platform, we show that drugs with different modes of action produce distinct responses in the physiological 3D cell spheroids compared to conventional 2D cell monolayers. Specifically, the anticancer drug 5-fluorouracil (5-FU) has higher anti-proliferative effects on 2D cultures whereas the hypoxia activated drug commonly referred to as tirapazamine (TPZ) are more effective against 3D cultures. The multiplexed 3D hanging drop culture and testing plate provides an efficient way to obtain biological insights that are often lost in 2D platforms. 相似文献
83.
Nguyen HT Tran HQ Nguyen TT Chau VM Bui KA Pham QL Nguyen MC Kim YH 《Chemical & pharmaceutical bulletin》2011,59(11):1417-1420
Ten oleanane-type saponins (1-10), including three new compounds, namely bifinosides A-C (1-3), were isolated from the roots of Panax bipinnatifidus SEEM. Their structures were elucidated on the basis of chemical and spectroscopic methods. 相似文献
84.
Tung HT Hwu Y Chen IG Tsai MG Song JM Kempson IM Margaritondo G 《Chemical communications (Cambridge, England)》2011,47(32):9152-9154
CuGaS(2) nanorods were synthesized by irradiating the precursor solution with intense X-rays. The products are single crystal nanorods with preferential [220] growth and a uniform size distribution. We also report on the photoresponse of drop-cast films of these nanorods. 相似文献
85.
Ding T Tian Y Liang K Clays K Song K Yang G Tung CH 《Chemical communications (Cambridge, England)》2011,47(8):2429-2431
Oxygen plasma etching of electrospun polymer fibers containing spherical colloids is presented as a new approach towards anisotropic colloidal nanoparticles. The detailed morphology of the resulting nanoparticles can be precisely controlled in a continuous way. The same approach is also amenable to prepare inorganic nanoparticles with double-sided patches. 相似文献
86.
Douville NJ Zamankhan P Tung YC Li R Vaughan BL Tai CF White J Christensen PJ Grotberg JB Takayama S 《Lab on a chip》2011,11(4):609-619
Studies using this micro-system demonstrated significant morphological differences between alveolar epithelial cells (transformed human alveolar epithelial cell line, A549 and primary murine alveolar epithelial cells, AECs) exposed to combination of solid mechanical and surface-tension stresses (cyclic propagation of air-liquid interface and wall stretch) compared to cell populations exposed solely to cyclic stretch. We have also measured significant differences in both cell death and cell detachment rates in cell monolayers experiencing combination of stresses. This research describes new tools for studying the combined effects of fluid mechanical and solid mechanical stress on alveolar cells. It also highlights the role that surface tension forces may play in the development of clinical pathology, especially under conditions of surfactant dysfunction. The results support the need for further research and improved understanding on techniques to reduce and eliminate fluid stresses in clinical settings. 相似文献
87.
88.
Tetraarylthiophenes were prepared by regioselective Suzuki cross-coupling reactions of tetrabromothiophene. 相似文献
89.
90.
Parton distribution functions consistent with neutrino and muon deep inelastic scattering as well as Drell-Yan pair production results have been extracted. This analysis incorporates experimental systematic errors which are the dominant errors in recent deep inelastic scattering experiments. The dependence of the results on factors such as kinematic cuts in the data, heavy target corrections, and choice of initial functional form are also explored. The form adopted is motivated by perturbative QCD and particularly useful in exploring the small-x extrapolation of the distributions. This is crucial for studying the range of predictions for Collider, HERA, and SSC/LHC cross sections. Representative distribution function sets are presented in a very compact parametrized form both in the DIS and MS-bar renormalization schemes.This work is partially supported by the National Science Foundation under Grant No. PHY89-05161. This work was also supported by Argonne National Laboratory during the 1988–89 academic year when the author was on Sabbatical leave at the Laboratory from IIT 相似文献