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101.
Vadukumpully S Basheer C Jeng CS Valiyaveettil S 《Journal of chromatography. A》2011,1218(23):3581-3587
The isolation and characterization of carbon nanofibers from soot obtained by burning natural oil is reported. The fibers were extracted from the soot with tetrahydrofuran followed by sonication. The carbon nanofibers were mixed with poly(vinyl alcohol) and electrospun to get the nanofiber mat. The extraction ability of electrospun nanofibers for the separation and preconcentration of aromatic compounds such as 3-nitroaniline, 4-chloroaniline, 4-bromoaniline and 3,4-dichloroaniline were tested and efficiently evaluated using high performance liquid chromatography. Under optimized conditions, the method showed good linearity in a range of 0.5–50 μg L−1 with correlation coefficient ranging from 0.989 to 0.998. High precision of the extraction with RSD values of 4.5–5.8% and low LOD value in a range of 0.009–0.081 μg L−1 for all aniline compounds were achieved. The proposed microextraction method offers advantages such as easy operation, high recovery, fast extraction, minimal use of organic solvent and elimination of tedious solvent evaporation and reconstitution steps. 相似文献
102.
Kwon KW Choi JC Suh KY Doh J 《Langmuir : the ACS journal of surfaces and colloids》2011,27(7):3238-3243
We present new methods that enable the fabrication of multiscale, multicomponent protein-patterned surfaces and multiscale topologically structured surfaces by exploiting the merits of two well-established techniques: capillary force lithography (CFL) and microscope projection photolithography (MPP) based on a protein-friendly photoresist. We further demonstrate that, when hierarchically organized micro- and nanostructures were used as a cell culture platform, human colon cancer cells (cell line SW480) preferentially adhere and migrate onto the area with nanoscale topography over the one with microscale topography. These methods will provide many exciting opportunities for the study of cellular responses to multiscale physicochemical cues. 相似文献
103.
Jaehong Kim Sung Heum Park Jinwoo Kim Shinuk Cho Youngeup Jin Joo Young Shim Hyunmin Shin Sooncheol Kwon Il Kim Kwanghee Lee Alan J. Heeger Hongsuk Suh 《Journal of polymer science. Part A, Polymer chemistry》2011,49(2):369-380
Newly designed 2H‐benzimidazole derivatives which have solubility groups at 2‐position have been synthesized and incorporated into two highly soluble carbazole based alternating copolymers, poly[2,7‐(9‐(1′‐octylnonyl)‐9H‐carbazole)‐alt‐5,5‐(4′,7′‐di(thien‐2‐yl)‐2H‐benzimidazole‐2′‐spirocyclohexane)] (PCDTCHBI) and poly[2,7‐(9‐(1′‐octylnonyl)‐9H‐carbazole)‐alt‐5,5‐(4′,7′‐di(thien‐2‐yl)‐2H‐benzimidazole‐2′‐spiro‐4′′‐((2′′′‐ethylhexyl)oxy)‐cyclohexane)] (PCDTEHOCHBI) for photovoltaic application. These alternating copolymers show low‐band gap properties caused by internal charge transfer from an electron‐rich unit to an electron‐deficient moiety. HOMO and LUMO levels are –5.53 and –3.86 eV for PCDTCHBI, and –5.49 and –3.84 eV for PCDTEHOCHBI, respectively. Optical band gaps of PCDTCHBI and PCDTEHOCHBI are 1.67 and 1.65 eV, respectively. The new carbazole based the 2H‐benzimidazole polymers show 0.11–0.13 eV lower values of band gaps as compared to that of carbazole based benzothiadiazole polymer, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), while keeping nearly the same deep HOMO levels. The power conversion efficiencies of PCDTCHBI and PCDTEHOCHBI blended with [6,6]phenyl‐C71‐butyric acid methyl ester (PC71BM) are 1.03 and 1.15%, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
104.
1,3-diproyloxycalix[4]arene azacrown ether was successfully synthesized in the fixed 1,3-alternate conformation which was confirmed by a solid state structure. 相似文献
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109.
A 3D porous metal-organic framework [Zn3(ntb)2(EtOH)2]n.4nEtOH (1) that generates 1D channels of honeycomb aperture has been prepared by the solvothermal reaction of Zn(NO3)(2).6 H2O and 4,4',4'-nitrilotrisbenzoic acid (H3NTB) in EtOH at 110 degrees C. Framework 1 exhibits reversible single-crystal-to-single-crystal transformations upon removal and rebinding of the coordinating EtOH as well as the EtOH guest molecules, which give rise to desolvated crystal [Zn3(ntb)2]n (1') and resolvated crystal [Zn3(ntb)2-(EtOH)2]n.4nEtOH (1'). The X-ray structures indicate that 3D host framework is retained during the transformations from 1 to 1' and from 1' to 1', but the coordination geometry of ZnII ions changes from/to trigonal bipyramid to/from tetrahedron, concomitant with the rotational rearrangement of a carboxylate plane of the NTB3- relative to its associated phenyl ring. To retain the single crystal integrity, extensive cooperative motions must exist between the molecular components throughout the crystal. Framework 1' exhibits permanent porosity, thermal stability up to 400 degrees C, and blue luminescence, and high storage capabilities for N2, H2, CO2, and CH4. 相似文献
110.
Inside Back Cover: Copper–Organic Framework Fabricated with CuS Nanoparticles: Synthesis,Electrical Conductivity,and Electrocatalytic Activities for Oxygen Reduction Reaction (Angew. Chem. Int. Ed. 49/2016) 下载免费PDF全文
Keumnam Cho Prof. Sung‐Hwan Han Prof. Myunghyun Paik Suh 《Angewandte Chemie (International ed. in English)》2016,55(49):15443-15443