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31.
Si Hyung Lee See Jo Kim Jaewook Nam Hyun Wook Jung Jae Chun Hyun 《Journal of Coatings Technology and Research》2014,11(1):47-55
As an indicator for determining the operability window in slot coating flow, the viscocapillary model considering various configurations of upstream and downstream slot die lips was tested and compared with Navier–Stokes two-dimensional model. Bead pressure and sloped lip angle conditions for uniform coating operation demarcated from leaking and bead break-up defects were quantitatively predicted from the position of upstream meniscus from both models. By comparing the results, it is confirmed that the viscocapillary model for many kinds of sloped die lips could predict the operability window accurately. It is also found that there exists vortex or recirculation regimes inside upstream and downstream coating bead regions, depending on the angles of sloped die lips, even for the stable coating flow. The flow control by die lip structure will be usefully applied to design the strategy for the reliable and optimal coating process, including vortex-free windows. 相似文献
32.
Jun-Tae Kim Seo Hee Jung Sun Young Kang Chung-Kyu Ryu Nam Sook Kang 《International journal of molecular sciences》2014,15(11):20403-20412
We report the discovery of aurora kinase inhibitor using the fragment-based virtual screening by multi-docking strategy. Among a number of fragments collected from eMololecules, we found four fragment molecules showing potent activity (>50% at 100 μM) against aurora kinase. Based on the explored fragment scaffold, we selected two compounds in our synthesized library and validated the biological activity against Aurora kinase. 相似文献
33.
Park TJ Lee SY Lee SJ Park JP Yang KS Lee KB Ko S Park JB Kim T Kim SK Shin YB Chung BH Ku SJ Kim do H Choi IS 《Analytical chemistry》2006,78(20):7197-7205
An efficient strategy for immobilizing proteins on a gold surface was developed by employing the gold binding polypeptide (GBP) as a fusion partner. Using the enhanced green fluorescent protein (EGFP), severe acute respiratory syndrome coronavirus (SARS-CoV) envelope protein (SCVme), and core streptavidin (cSA) of Streptomyces avidinii as model proteins, specific immobilization of the GBP-fusion proteins onto the gold nanoparticles and generation of protein nanopatterns on the bare gold surface were demonstrated. The GBP-fused SCVme bound to gold nanoparticles successfully interacted with its antibody and showed changes in absorbance and color, allowing efficient diagnosis of SARS-CoV. The fusion proteins could be successfully immobilized on the gold surface by nanopatterning and microcontact printing as examined by atomic force microscopy and surface plasmon resonance analysis. The poly(dimethylsiloxane) microfluidic channels were created on the gold surface and were used for antigen-antibody and DNA-DNA interaction studies. Specific immobilization of GBP-EGFP fusion protein and its interaction with the antibody in the microchannels could be demonstrated. By immobilizing the DNA probe through the use of GBP-fused cSA, specific hybridization of the target DNA prepared from Salmonella could also be achieved. The GBP-fusion method allows immobilization of proteins onto the gold surface without surface modification and in bioactive forms suitable for studying protein-protein, DNA-DNA, and other biomolecular interaction studies. Furthermore, these studies can be carried out in a microfluidic system, which allows high-throughput analysis of biomolecular interactions. 相似文献
34.
Peter H. Foss Huan‐Chang Tseng John Snawerdt Yuan‐Jung Chang Wen‐Hsien Yang Chia‐Hsiang Hsu 《Polymer Composites》2014,35(4):671-680
In the automotive industry, glass‐filled thermoplastics are used in air intake manifolds, radiator tanks, and many other parts. However, widespread application of glass‐filled thermoplastic materials has been limited in many cases by the inability to accurately predict performance and durability. Since a more accurate fiber orientation prediction will lead to more accurate local mechanical property predictions, this work investigated a recently proposed mathematic model of fiber suspension rheology, which considers the anisotropic fiber diffusion and fiber–matrix interaction from a microscopic viewpoint. The new model proved able to predict many details of the fiber orientation distribution and could be applied advantageously as part of the product and manufacturing development processes. POLYM. COMPOS., 35:671–680, 2014. © 2013 Society of Plastics Engineers 相似文献
35.
Bit-Na Go Yang Doo Kim Kyoung suk Oh Chaehyun Kim Hak-Jong Choi Heon Lee 《Nanoscale research letters》2014,9(1):486
To provide a front transparent electrode for use in highly efficient hydrogenated amorphous silicon (a-Si:H) thin-film solar cells, porous flat layer and micro-patterns of zinc oxide (ZnO) nanoparticle (NP) layers were prepared through ultraviolet nanoimprint lithography (UV-NIL) and deposited on Al-doped ZnO (AZO) layers. Through this, it was found that a porous micro-pattern of ZnO NPs dispersed in resin can optimize the light-trapping pattern, with the efficiency of solar cells based on patterned or flat mesoporous ZnO layers increased by 27% and 12%, respectively. 相似文献
36.
Tae-Woo Kim Tasneem Islam Kang-Yeoun Jung 《Journal of Industrial and Engineering Chemistry》2010,16(3):461-466
In the course of our studies directed towards the discovery of novel non-steroidal anti-inflammatory agents (NSAIDs), which are expected to have improved drug efficacy and better toxicity profile than diclofenac, we have synthesized new derivatives of diclofenac phosphonates. These phosphonate analogs were efficiently prepared from commercially available 2-hydroxymethylaniline in three steps. The 2-hydroxymethylaniline was converted to the azide in reasonable yield. Click chemistry with a variety of alkynes followed by Arbuzov reaction resulted in a series of triazole based phosphonate products. Our inhibitors are designed to reduce the gastrointestinal bleeding caused by diclofenac by substituting the carboxylic acid group with the phosphonate group and in addition replacing with the triazole ring would allow the flexibility to explore the importance of both hydrophilicity and hydrophobicity of the ring at the active site. 相似文献
37.
Jin Sup Yang Won Young Jung Gun-Dae Lee Seong Soo Park Seong-Soo Hong 《Topics in Catalysis》2010,53(7-10):543-549
The effect of the pretreatment conditions on the catalytic combustion of benzene over copper oxides supported on SBA-15 was investigated. The catalytic activities of the reduced catalysts were higher than those of the unreduced catalysts, indicating that the metallic Cu is much more active than the copper oxides. 相似文献
38.
Zhongqing Zheng Kent C. Johnson Zhihua Liu Thomas D. Durbin Shaohua Hu Tao Huai David B. Kittelson Heejung S. Jung 《Journal of aerosol science》2011,42(12):883-897
A Particle Measurement Program (PMP) compliant system, an AVL advanced particle counter (APC) and an alternative volatile particle removal system, a catalytic stripper (CS) were evaluated and compared for measuring solid particle number (PN) emissions. The evaluations and comparisons were conducted using sulfuric acid and hydrocarbon particles as model volatile particles in laboratory tests, and diluted exhaust from a diesel particle filter (DPF)-equipped heavy-duty diesel vehicle operated on a heavy-duty chassis dynamometer under steady speed conditions at two different engine loads. For the laboratory test, both the APC and CS removed more than 99% of the volatile particles in terms of PN when using aerosols composed of pure sulfuric acid or hydrocarbons. When using laboratory test aerosols consisting of mixtures of sulfuric acid and hydrocarbons more than 99% of the particles were removed by the APC but the surviving particles were no longer entirely volatile, 12–14% were solid. For the chassis dynamometer test, PN emissions between 3 and 10 nm downstream the APC were ∼2 and 7 times higher than the PN emissions of particles above 10 nm at the 74% and 26% engine load, respectively. At the 26% engine load, PN level of the 3–10 nm particles downstream the APC were significantly higher than that in the dilution tunnel, demonstrating that the APC was making 3–10 nm particles. The PN emission of 3–10 nm particles downstream the APC was related to the heating temperature of the APC evaporation tube, suggesting these particles are artifacts formed by renucleation of semivolatiles. Considerably fewer particles between 3 to 10 nm were seen downstream of the CS for both engine loads due mainly to removal of semivolatile material by the catalytic substrates, although some of this difference could be attributed to diffusion and thermophoretic losses. The findings of this study imply that improvement of the current PMP protocol would be necessary if the PMP were to be used in other applications where the PN emissions of particles below 23 nm are important. 相似文献
39.
Shu‐Ping Lee Shyh‐Chyun Yang Yen‐Shih Cheng Wan‐Jung Lien Lean‐Teik Ng 《European Journal of Lipid Science and Technology》2010,112(7):712-719
Tocotrienols, a group of important phytonutrients of palm oil, have been shown to possess antioxidant, anticancer, neuroprotectory, and anti‐inflammatory activities. In this study, our objective was to examine the protective effects of tocotrienol‐rich fraction (TRF) from palm oil on chronic carbon tetrachloride (CCl4)‐induced hepatotoxicity in rats. Animals were subjected to vehicle only (control), CCl4 only, CCl4 + 100 mg/kg silymarin (silymarin), CCl4 + 25 mg/kg TRF (TRF‐25) and CCl4 + 50 mg/kg TRF (TRF‐50) treatments for a period of 8 wks. Results showed that daily oral administration of TRF‐25, TRF‐50, and silymarin prevented the elevation of serum glutamate oxalate transaminase (sGOT) and glutamate pyruvate transaminase (sGPT), liver thiobarbituric acid reactive substances (TBARS), triglycerides and total cholesterol levels, as well as enhancing the liver catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels in rats with hepatotoxicity. At 50 mg/kg, the hepatoprotection of TRF was as good as or better than silymarin (100 mg/kg) in normalization of oxidative stress parameters in liver injury rats. These results suggest that TRF exerts effective protection against chronic CCl4‐induced hepatic injury in rats, and its mechanism of action could be related to reducing oxidative stress in the liver tissue. 相似文献
40.
Jung Peter Kammerlander Karl Berens Friedbert Plechinger Jorg 《International Journal of Wireless Information Networks》1997,4(2):63-87
The combination of code division multiple access(CDMA) and multicarrier (MC) transmission techniques,termed MC-CDMA, is considered a promising alternative toconventional DS (direct sequence)-CDMA. For this reason, recent research activities haveconcentrated on the application of MC-CDMA to mobileradio systems. In this paper an MC-CDMA concept which iswell suited for mobile radio applications is described. The described MC-CDMA concept overcomesdisadvantages of previously proposed concepts. InMC-CDMA mobile radio systems, signal reception isimpaired by time-varying multipath propagation. Theimpairments can be reduced by applying diversitytechniques. Coherent receiver antenna diversity (CRAD)is especially attractive because only the signalprocessing at the receivers must be modified. In thiscommunication, the application of CRAD in combination withjoint detection (JD) techniques to the more criticaluplink of MC-CDMA mobile radio systems is investigated.It is explained that the deployment of JD techniques for CRAD is an effective countermeasure againstthe influence of the mobile radio channel on the systemperformance. Four JD techniques for CRAD which areapplicable to MC-CDMA are presented. Their performances are studied in bad urban, typical urban, andtypical macrocellular environments. It is shown thatMC-CDMA allows a favorable performance compared to otherCDMA concepts. 相似文献