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951.
The effects of antimony (Sb) doping on solution‐processed indium oxide (InOx) thin film transistors (TFTs) were examined. The Sb‐doped InSbO TFT exhibited a high mobility, low gate swing, threshold voltage, and high ION/OFF ratio of 4.6 cm2/V s, 0.29 V/decade, 1.9 V, and 3 × 107, respectively. The gate bias and photobias stability of the InSbO TFTs were also improved by Sb doping compared to those of InOx TFTs. This improvement was attributed to the reduction of oxygen‐related defects and/or the existence of the lone‐pair s‐electron of Sb3+ in amorphous InSbO films. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
952.
Previously, plasma‐enhanced dry etching has been used to generate three‐dimensional GaAs semiconductor structures, however, dry etching induces surface damages that degrade optical properties. Here, we demonstrate the fabrication method forming various types of GaAs microstructures through the combination etching process using the wet‐chemical solution. In this method, a gold (Au)‐pattern is employed as an etching mask to facilitate not only the typical wet etching but also the metal‐assisted chemical etching (MacEtch). High‐aspect‐ratio, tapered GaAs micropillars are produced by using [HF]:[H2O2]:[EtOH] as an etching solution, and their taper angle can be tuned by changing the molar ratio of the etching solution. In addition, GaAs microholes are formed when UV light is illuminated during the etching process. Since the wet etching process is free of the surface damage compared to the dry etching process, the GaAs microstructures demonstrated to be well formed here are promising for the applications of III–V optoelectronic devices such as solar cells, laser diodes, and photonic crystal devices. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
953.
Jae Hoon Lim Sung-Yu Hong Soo Jung Kang Hyun-Ju Doh Jaewoo Song Jong Rak Choi Kwang-Hoe Chung Jinsub Choi 《Electrochemistry communications》2009,11(11):2141-2144
Simple and cost-effective process for the fabrication of a nanodot strip which can electrochemically determine blood coagulation time was described in detail. We observed that the beginning of blood coagulation on the nanodot surface gives rise to increase in resistance against current flow, leading to suddenly increase in potential when constant current is applied between the nanodot electrodes. Interestingly, such dramatic increase in potential was not observed in the plain surface and non-controlled rough surface. 相似文献
954.
Md. Iqbal Rouf Mamun Jong Hyouk Park Jeong‐Heui Choi Hee Kwon Kim Woo Jung Choi Seong‐Soo Han Kyungsup Hwang Nam‐IK Jang Mohamed Ezzat Assayed Mohamed Anwer El‐Dib Ho‐Chul Shin A. M. Abd El‐Aty Jae‐Han Shim 《Journal of separation science》2009,32(4):559-574
Several methods used for the multiresidue analysis of pesticides from the environment and drinking water have been reported. However, most of these reports dealt with a small number of targeted pesticides or some special groups. A method that is simple, faster, and more cost‐effective than the environmental protection agency (EPA) method has been developed for the analysis of 82 frequently used pesticides in water samples obtained from Yeongsan and Sumjin rivers, as well as rice fields located in various locations around the two rivers. The samples were extracted by dichloromethane, and the pesticides were analyzed using a GC‐electron capture detector (ECD), followed by confirmation with GC‐MS. Recoveries were found to be between 82 and 120.1% for most of the tested pesticides, which were in agreement with the standard values dictated by the EPA. The method was potentially applied to 66 water samples for human consumption and 90 water samples from the rice fields and irrigation ditches that were collected from June to September 2007. Oxadiazon, butachlor, and alachlor were detected in some of the river water samples collected in June, iprobenfos (IBP) was detected in samples collected in August, and no pesticide was detected in September. On the other hand, chlorpyrifos‐methyl, IBP, hexaconazole, diazinon, oxadiazon, butachlor, and isoprothiolane were detected at relatively high concentrations in 48 rice paddy field water samples collected between June and September 2007. Alachlor in one sample and procymidone in some of the rice paddy field water samples were also detected in trace amounts. The results were consistent with the temporal pattern of pesticide application in Korean rice fields. 相似文献
955.
Yeon Jae Ko Haopeng Wang Xiang Li Kit. H. Bowen Prof. Frédéric Lecomte Dr. Charles Desfrançois Prof. Jean‐Christophe Poully Gilles Grégoire Dr. Jean Pierre Schermann Dr. 《Chemphyschem》2009,10(17):3097-3100
Gas‐phase intrinsic structures of intact neutral and anionic glutathione (GSH) have been determined by means of a combination of negative ion photo‐electron spectroscopy and quantum chemistry calculations. The inferred structures of the neutral parents of those peptide anions are canonical (non‐zwitterionic). These intrinsic structures are compared to those already known in aqueous solution or determined by crystallography in binding sites of enzymes. 相似文献
956.
Thromboxane A2 modulates migration, proliferation, and differentiation of adipose tissue-derived mesenchymal stem cells 总被引:1,自引:0,他引:1
Doo Hee Yun Hae Young Song Mi Jeong Lee Mi Ra Kim Min Young Kim Jung Sub Lee Jae Ho Kim 《Experimental & molecular medicine》2009,41(1):17-24
Prostanoid metabolites are key mediators in inflammatory responses, and accumulating evidence suggests that mesenchymal stem cells (MSCs) can be recruited to injured or inflamed tissues. In the present study, we investigated whether prostanoid metabolites can regulate migration, proliferation, and differentiation potentials of MSCs. We demonstrated herein that the stable thromboxane A2 (TxA2) mimetic U46619 strongly stimulated migration and proliferation of human adipose tissue-derived MSCs (hADSCs). Furthermore, U46619 treatment increased expression of α-smooth muscle actin (α-SMA), a smooth muscle marker, in hADSCs, suggesting differentiation of hADSCs into smooth muscle-like cells. U46619 activated ERK and p38 MAPK, and pretreatment of the cells with the MEK inhibitor U0126 or the p38 MAPK inhibitor SB202190 abrogated the U46619-induced migration, proliferation, and α-SMA expression. These results suggest that TxA2 plays a key role in the migration, proliferation, and differentiation of hADSCs into smooth muscle-like cells through signaling mechanisms involving ERK and p38 MAPK. 相似文献
957.
Jong Il Lee Yun Jae Kim Heejin Bae Sung Suk Cho Jung-Hyun Lee Suk-Tae Kwon 《Applied biochemistry and biotechnology》2010,160(6):1585-1599
The Thermococcus peptonophilus (Tpe) DNA polymerase gene was expressed under the control of the T7lac promoter on pET-22b(+) in Escherichia coli BL21-CodonPlus(DE3)-RIL in order to fully elucidate its biochemical properties and evaluate its feasibility in polymerase
chain reaction (PCR) application. The expressed enzyme was then purified by heat treatment followed by two steps of column
chromatography after which optimum pH and temperature of the enzyme were evaluated to be 7.0 and 75 °C, respectively. The
optimal buffer for PCR with Tpe DNA polymerase consisted of 50 mM Tris–HCl (pH 8.0), 2 mM MgCl2, 80 mM KCl, and 0.02% Triton X-100. Tpe DNA polymerase revealed a 3.6-fold higher fidelity (3.37 × 10−6) than Taq DNA polymerase (12.13 × 10−6) and performed significantly more efficiently in PCR amplification than both Taq and Pfu DNA polymerases. Ratios of 31:1 of Taq to Tpe DNA polymerases allowed PCR amplification of targets up to 15 kb in length with a 2.2-fold higher fidelity than Taq DNA polymerase. The results of the PCR experiments indicate that Tpe DNA polymerase may provide a higher fidelity DNA amplification in a shorter reaction time. 相似文献
958.
Song JH Couzis A Lee JW 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18119-18124
Macroscopic interfacial interactions between cyclopentane (CP) hydrates and various surfactants droplets are examined in a CP/n-decane oil mixture. Initial contact force and subsequent z-axis dependent retraction force are measured utilizing a high-resolution microbalance integrated with a micrometer-precision stage. The resulting retraction force is utilized to determine the overall adhesion energy of the system. In addition, interfacial tensions and contact angles of the system are examined to further understand the effect of surface-active agents and substrates on the initial contact and retraction forces. 相似文献
959.
Organic and inorganic binder-coating properties for immobilization of photocatalytic ZnO nanopowders
Park Sung Choi Gil Rak Lee Jae Chun Kim Youn Cheol Oh Daniel Cho Sungkap Lee Ju-Hyeon 《Research on Chemical Intermediates》2010,36(6-7):819-825
Research on Chemical Intermediates - Five kinds of organic binders, three kinds of inorganic binders, and four kinds of organic–inorganic double-layer binders were prepared to immobilize... 相似文献