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71.
The device performances of spin-coated and stamp transfer printed devices were compared. There was little difference of morphology between the spin-coated and stamp transfer printed devices. However, the stamp transfer printing process was better than the spin-coating process in terms of current density, light-emitting efficiency and lifetime. In particular, the lifetime of the stamp transfer printed device was doubled compared with that of the spin-coated device. 相似文献
72.
Soon Ok Jeon Kyoung Soo Yook Chul Woong Joo Hyo Suk Son Sang Eok Jang Jun Yeob Lee 《Organic Electronics》2009,10(5):998-1000
High efficiency red phosphorescent organic light-emitting diodes have been developed using a spirobenzofluorene type phosphine oxide (SPPO2) as a host material. The SPPO2 had a high glass transition temperature of 119 °C and a smooth surface morphology with a surface roughness less than 1 nm. The red device with the SPPO2 as a host showed a quantum efficiency of 14.3% with a current efficiency of 20.4 cd/A. 相似文献
73.
Hong Kyoon Choi Mun Ho Kim Sang Hyuk Im O Ok Park 《Advanced functional materials》2009,19(10):1594-1600
Hexagonally arrayed structures of colloidal crystals with uniform surface are a good candidate for master molds to be used in soft lithography. Here, the fabrication of periodically arrayed nanostructures using poly(dimethylsiloxane) (PDMS) molds based on three‐dimensionally (3D) ordered colloidal crystals is reported. A robust, high‐quality 3D colloidal‐crystal master molds is prepared using the colloidal suspension containing a water‐soluble polymer. The surface patterns of the 3D colloidal crystals can then be transferred onto a polymer film via soft lithography, by means of the replication of the surface pattern with PDMS. Various hexagonally arrayed nanostructure patterns can be fabricated, including close‐packed and non‐close‐packed 2D arrays and honeycomb structures by the structural modification of the 3D colloidal‐crystal templates. The replicated hexagonally arrayed structures can also be used as templates for producing colloidal crystals with 2D superlattices. 相似文献
74.
Kyoung Soo Yook Soon Ok Jeon Chul Woong Joo Jun Yeob Lee 《Journal of Industrial and Engineering Chemistry》2009,15(6):907-909
Hole injection properties of copper phthalocyanine (CuPc) layer doped with hexaazatriphenylene–hexacarbonitrile (HAT) were studied by changing the doping concentration of HAT. Hole injection efficiency of CuPc layer was improved by doping of HAT as a p-dopant and a maximum current density was obtained at a HAT doping concentration of 10%. The use of HAT doped CuPc layer as a hole injection layer improved the current efficiency of green phosphorescent organic light-emitting diodes. 相似文献
75.
Ok Bin Kim Heinrich Luftmann Alexander Steinbüchel 《European Journal of Lipid Science and Technology》2009,111(10):972-978
Glycidol was biologically derivatized by the unspecific wax ester synthase/acyl coenzyme A (acyl‐CoA): diacylglycerol acyltransferase (WS/DGAT) from Acinetobacter baylyi ADP1 into glycidyl acyl ester. Catalysis of in vitro conversion of glycidol to glycidyl acyl ester by the WS/DGAT from A. baylyi was verified by (i) a radiometric assay, (ii) thin‐layer chromatography and (iii) also by ESI‐MS. A specific activity of 50 nmol·mg–1·min–1 was obtained when 10 mM glycidol and 5 µM palmitoyl‐CoA were used. In vivo synthesized glycidyl acyl esters in recombinant E. coli were detected and quantified by staining with the epoxide‐specific reagent 4‐(4‐nitrobenzyl)‐pyridine. Of glycidyl acyl esters, 1.5 mg/L was obtained from the culture in the presence of 10 mM glycidol and 10 mM oleate. 相似文献
76.
The preparation and microwave dielectric properties of ZnAl2O4-based glass–ceramic composites were investigated. Using zinc borosilicate (ZBS) glass and Al2O3, glass–ZnAl2O4 composites with high quality factor was successfully prepared at temperatures below 950 °C. The linear shrinkage for 50 vol% ZBS glass–ZnAl2O4 composite showed a steep increase up to 650 °C and a plateau between 700 °C and 950 °C, implying that one-stage densification process occurred. The crystallization of ZnAl2O4 was observed above 700 °C and an insufficient densification occurred due to the consumption of the glass. As the sintering temperature increased, the quality factor (Q × f0) showed an increase with an S-type curve whereas the dielectric constant was almost constant. The formation of ZnAl2O4 might correspond to the increase of Q × f0; a high value of 17,757 GHz (1415 at 12.6 GHz) was obtained for the specimen sintered at 900 °C. 相似文献
77.
78.
Chang HW Sung Y Kim KH Nam YD Roh SW Kim MS Jeon CO Bae JW 《Environmental science & technology》2008,42(16):6058-6064
A crucial problem in the use of previously developed genome-probing microarrays (GPM) has been the inability to use uncultivated bacterial genomes to take advantage of the high sensitivity and specificity of GPM in microbial detection and monitoring. We show here a method, digital multiple displacement amplification (MDA), to amplify and analyze various genomes obtained from single uncultivated bacterial cells. We used 15 genomes from key microbes involved in dichloromethane (DCM)-dechlorinating enrichment as microarray probes to uncover the bacterial population dynamics of samples without PCR amplification. Genomic DNA amplified from single cells originating from uncultured bacteria with 80.3-99.4% similarity to 16S rRNA genes of cultivated bacteria. The digital MDA-GPM method successfully monitored the dynamics of DCM-dechlorinating communities from different phases of enrichment status. Without a priori knowledge of microbial diversity, the digital MDA-GPM method could be designed to monitor most microbial populations in a given environmental sample. 相似文献
79.
Analysis of yeast and archaeal population dynamics in kimchi using denaturing gradient gel electrophoresis 总被引:2,自引:0,他引:2
Chang HW Kim KH Nam YD Roh SW Kim MS Jeon CO Oh HM Bae JW 《International journal of food microbiology》2008,126(1-2):159-166
Kimchi is a traditional Korean food that is fermented from vegetables such as Chinese cabbage and radish. Many bacteria are involved in kimchi fermentation and lactic acid bacteria are known to perform significant roles. Although kimchi fermentation presents a range of environmental conditions that could support many different archaea and yeasts, their molecular diversity within this process has not been studied. Here, we use PCR-denaturing gradient gel electrophoresis (DGGE) targeting the 16S and 26S rRNA genes, to characterize bacterial, archaeal and yeast dynamics during various types of kimchi fermentation. The DGGE analysis of archaea expressed a change of DGGE banding patterns during kimchi fermentation, however, no significant change was observed in the yeast DGGE banding patterns during kimchi fermentation. No significant difference was indicated in the archaeal DGGE profile among different types of kimchi. In the case of yeasts, the clusters linked to the manufacturing corporation. Haloarchaea such as Halococcus spp., Natronococcus spp., Natrialba spp. and Haloterrigena spp., were detected as the predominant archaea and Lodderomyces spp., Trichosporon spp., Candida spp., Saccharomyces spp., Pichia spp., Sporisorium spp. and Kluyveromyces spp. were the most common yeasts. 相似文献
80.