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991.
A graphene oxide/titania (GO/TiO(2)) nanocomposite was fabricated by a facile electrostatic attraction method. With high polarization of GO particles and a relatively high dielectric constant of TiO(2) nanoparticles, the GO/TiO(2) nanocomposite is observed to be a potential electro-responsive electrorheological material under an applied electric field. 相似文献
992.
Choi SH Hwang IS Lee JH Oh SG Kim ID 《Chemical communications (Cambridge, England)》2011,47(33):9315-9317
Microstructural evolution of spinel Zn(2)SnO(4) nanofibers was manipulated via an in situ phase separation process of inorganic precursors and a matrix polymer during electrospinning and calcination. Chemiresistive gas sensors using porous Zn(2)SnO(4) fibers exhibited superior C(2)H(5)OH sensing response. 相似文献
993.
Park JS Jeong S Chang DW Kim JP Kim K Park EK Song KW 《Chemical communications (Cambridge, England)》2011,47(16):4736-4738
We describe a novel anisotropic supramolecular gel made of cyclodextrin-dye, in which physical gelation is completed by lithium salt. Rheological experiment reveals the elastic behaviors of the hydrogel, and high ionic conductivity represents a good mobility of ions inside the gel matrix. 相似文献
994.
Paek S Choi H Kim C Cho N So S Song K Nazeeruddin MK Ko J 《Chemical communications (Cambridge, England)》2011,47(10):2874-2876
A new series of stable, unsymmetrical squaraine near-IR sensitizers (JK-216 and JK-217), which are assembled using both thiophenyl pyrrolyl and indolium groups, exhibit a panchromatic light harvesting up to 780 nm. The JK-216 based cell exhibited a record efficiency of 6.29% for near-IR DSSCs. In addition, the JK-217 device showed an excellent stability under a light soaking test at 60 °C for 1000 h. 相似文献
995.
Park J Lim DH Lim HJ Kwon T Choi JS Jeong S Choi IH Cheon J 《Chemical communications (Cambridge, England)》2011,47(15):4382-4384
The immune-response of macrophages is an important area of investigation since it represents the major pathway by which early-stage defense barriers are established in skin, lungs, and mucosal systems to counteract foreign objects. In this study, we have examined the size-dependent inflammatory and toxicological effects of nanostructured silver particles (nano-Ag) on macrophage immune cells. 相似文献
996.
Kim TI Park J Park S Choi Y Kim Y 《Chemical communications (Cambridge, England)》2011,47(47):12640-12642
We have presented a fluorescent probe 1 that exhibits a fluorescence turn-on signal upon reaction with tyrosinase, and we show that it is readily employed for the assessment of tyrosinase activity and tyrosinase inhibitor activity in buffered aqueous solution, and further utilized for the visualization of endogenous tyrosinase activity in living melanoma cells. 相似文献
997.
For the first time, employment of nicotinamide coenzyme NAD analogs has overcome the limitations of NAD in electrochemical regeneration. It has been shown that NAD analogs, APAD and PAAD, were electrochemically reduced more efficiently than original NAD and that the stability of their reduced products was also much higher than NADH. 相似文献
998.
Kim YS Bae SY Kim KH Lee TW Hur JA Hoang MH Cho MJ Kim SJ Kim Y Kim M Lee K Lee SJ Choi DH 《Chemical communications (Cambridge, England)》2011,47(31):8907-8909
A new pyrene-cored π-conjugated molecule has been synthesized through Sonogashira coupling reaction. The single-crystalline microribbon-based FET exhibited the highest mobility of 0.7 cm(2) V(-1) s(-1) (I(on)/I(off) > 10(6)). Single-crystalline microribbons were employed to operate in an organic phototransistor (OPT) under very low light intensity (I = 5.6 μW cm(-2)). 相似文献
999.
Choi J Jin J Jung IG Kim JM Kim HJ Son SU 《Chemical communications (Cambridge, England)》2011,47(18):5241-5243
Through a solution approach, SnSe(2) nanoplate-graphene composites were prepared and applied as anode materials in lithium ion batteries, showing promising storage performance superior to SnSe(2) nanoplates or graphene alone. 相似文献
1000.
Rho HS Ghimeray AK Yoo DS Ahn SM Kwon SS Lee KH Cho DH Cho JY 《Molecules (Basel, Switzerland)》2011,16(4):3338-3344
The objective of this study was to examine the biological activity of kaempferol and its rhamnosides. We isolated kaempferol (1), a-rhamnoisorobin (2), afzelin (3), and kaempferitrin (4) as pure compounds by far-infrared (FIR) irradiation of kenaf (Hibiscus cannabinus L.) leaves. The depigmenting and anti-inflammatory activity of the compounds was evaluated by analyzing their structure-activity relationships. The order of the inhibitory activity with regard to depigmentation and nitric oxide (NO) production was kaempferol (1) > a-rhamnoisorobin (2) > afzelin (3) > kaempferitrin (4). However, a-rhamnoisorobin (2) was more potent than kaempferol (1) in NF-kB-mediated luciferase assays. From these results, we conclude that the 3-hydroxyl group of kaempferol is an important pharmacophore and that additional rhamnose moieties affect the biological activity negatively. 相似文献