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51.
Effect of solvent on electrical conductivity and gas sensitivity of PEDOT: PSS polymer composite films 下载免费PDF全文
Jun Sung Hwang Tae Hwan Oh Se Hyun Kim Sung Soo Han Sung Jun Lee Se Geun Lee Young Jae Lee Seung Soon Jang 《应用聚合物科学杂志》2015,132(40)
Poly(3,4‐ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT:PSS) was blended with polyethylene oxide (PEO) and polyvinyl alcohol (PVA) and composite film was cast. Additional solvents of dimethyl sulfoxide (DMSO) and ethylene glycol (EG) were mixed and their effects on electrical conductivity and structural changes were investigated. The electrical conductivity increased in response to the additional solvent, leading to an increase in the PEDOT ratio relative to the control. PEDOT:PSS/PEO composite film had a much higher electrical conductivity than PEDOT:PSS/PVA. When blended with PEO, the quinoid structure revealed by Raman spectroscopy increased relative to the PVA‐blended case, indicating higher electrical conductivity. The current–voltage response and gas sensitivity showed much better performance in PEDOT:PSS/PEO/DMSO composite film. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42628. 相似文献
52.
Hee Jeong Yoo Kyung Kim In Hyang Kim Seong-Hwan Rho Jong-Eun Park Ki Young Lee Soon Ae Kim Byung Yoon Choi Namshin Kim 《International journal of molecular sciences》2015,16(3):5697-5713
Rubinstein-Taybi syndrome (RSTS) is a rare condition with a prevalence of 1 in 125,000–720,000 births and characterized by clinical features that include facial, dental, and limb dysmorphology and growth retardation. Most cases of RSTS occur sporadically and are caused by de novo mutations. Cytogenetic or molecular abnormalities are detected in only 55% of RSTS cases. Previous genetic studies have yielded inconsistent results due to the variety of methods used for genetic analysis. The purpose of this study was to use whole exome sequencing (WES) to evaluate the genetic causes of RSTS in a young girl presenting with an Autism phenotype. We used the Autism diagnostic observation schedule (ADOS) and Autism diagnostic interview revised (ADI-R) to confirm her diagnosis of Autism. In addition, various questionnaires were used to evaluate other psychiatric features. We used WES to analyze the DNA sequences of the patient and her parents and to search for de novo variants. The patient showed all the typical features of Autism, WES revealed a de novo frameshift mutation in CREBBP and de novo sequence variants in TNC and IGFALS genes. Mutations in the CREBBP gene have been extensively reported in RSTS patients, while potential missense mutations in TNC and IGFALS genes have not previously been associated with RSTS. The TNC and IGFALS genes are involved in central nervous system development and growth. It is possible for patients with RSTS to have additional de novo variants that could account for previously unexplained phenotypes. 相似文献
53.
54.
In this work, we investigated the effects of quantum dot (QD) annealing (as-grown, 600°C-annealed, and 750°C-annealed) on the preliminary performances of 1.3-μm InAs-InGaAs-GaAs quantum dot electroabsorption modulators (QD-EAMs). Both extinction ratio and insertion loss were found to vary inversely with the annealing temperature. Most importantly, the 3-dB response of the 750°C-annealed lumped-element QD-EAM was found to be 1.6 GHz at zero reverse bias voltage - the lowest reverse bias voltage reported. We believe that this work will be beneficial to researchers working on on-chip integration of QD-EAMs with other devices since energy consumption will be an important consideration. 相似文献
55.
Ji‐Kang Jeong Young‐Wook Kim Hye‐Sun Choi Dong Sun Lee Soon‐Ah Kang Kun‐Young Park 《International Journal of Food Science & Technology》2011,46(10):2015-2021
Kimchi was fermented in onggi and other containers at 4 °C for 4 weeks. Two types of onggi were used: glazed and nonglazed onggi. Other containers such as polyethylene plastic containers, polypropylene containers for use in a kimchi refrigerator, stainless steel and glass bottles were used. During the fermentation, kimchi fermented in onggi showed relatively stable acidity change compared with those in the other containers. Also it showed higher lactic acid bacteria multiplication (108–109 cfu g?1 at 4th week) but slower general aerobic bacteria multiplication than the others. The springiness of kimchi fermented in onggi was more than 50% at 4th week, it is higher than the others. Its carbonic acid taste and overall acceptability were excellent in sensory evaluations. The antioxidative and cancer‐cell antiproliferative activities were also greater in kimchi fermented in onggi than the others. Between the two types of onggi, nonglazed onggi showed better results in both properties and functionalities of kimchi. Onggi showed higher gas permeability than polyethylene plastic containers and glass bottles because of its porous structure, and lactic acid bacteria could have benefited from this condition. It possibly contributes to optimal ripening of kimchi resulting in better properties, especially texture and taste, and health functionalities. 相似文献
56.
This letter proposes an open‐ended waveguide antenna with a single split‐ring resonator. In contrast to the waveguide antennas incorporating multiple rings reported in a previous study, which exhibited narrow bandwidth, the proposed antenna uses only one ring to achieve broader bandwidth while keeping the aperture small. A single ring has a relatively low quality factor compared to multiple rings. The simulated and measured fractional bandwidth was 4.13% and 4.03%, respectively, which is much broader than the fractional bandwidth of about 1% demonstrated in a previous study. This simple technique can be used in many applications that require small apertures including near‐field probes and array elements. 相似文献
57.
Kyung Soon Jang Tae Won Kang Kee Sung Lee Chul Kim Tae-Woo Kim 《Journal of Mechanical Science and Technology》2010,24(6):1265-1271
Curved structural members are widely seen in our surroundings, such as railway supports in playgrounds resembling a c-ring
structure. The common geometry of the curved member consists of a segment of a circular ring with a uniform width. The curved
section is of constant width in most cardiovascular stents. This study focuses on curved strut members whose width changes
along the curved segment. The location of the maximum equivalent stress varies depending on the manner in which the width
changes. When the width is constant or larger toward the top, the maximum equivalent stress is developed at the top. Meanwhile,
when the area is reduced toward the bottom, the largest equivalent stress is developed some distance from the top. Simple
equations, based on the mechanics of materials and the theory of elasticity, were compared favorably with the results from
finite element analysis. Included are elaborations of the distribution of the change of stress. The suggested strategy of
changing the width, with refinements, could be applied to the optimal design of structural members, including pipes and medical
devices such as stents. 相似文献
58.
Mechanical properties and durability of PMMA impregnated mortar 总被引:1,自引:0,他引:1
Priya Nair Du Hyun Ku Chul Woo Lee Jung Soon Park Hun Young Park Won Mook Lee 《Korean Journal of Chemical Engineering》2010,27(1):334-339
Polymer impregnated concrete (PIC) is known to exhibit better strength and durability characteristics than the other classes
of polymer cement composites. In the work described herein the monomer was impregnated into cement mortar and polymerized
by two methods — the conventional thermal method and using microwaves. The mechanical properties and durability characteristics
of the samples and on exposure to chemical environments were then evaluated. The above studies revealed that the strengths
of PIC specimens were almost 2–3 times better than those of conventional cement mortars. The chemical resistance was also
found to be superior even on prolonged exposure to the chemical media. This may be attributed to the protective layer formed
by the polymer on the cement mortar, which prevents the external chemical media from interacting with the cement particles.
The properties of the PIC specimens prepared by both methods have also been compared and discussed in this paper. 相似文献
59.
Irisappan Ganesh Sambandam Ravikumar Si Jae Park Seung Hwan Lee Soon Ho Hong 《Korean Journal of Chemical Engineering》2013,30(7):1443-1447
The malate-pyruvate conversion pathway is catalyzed by two malic enzyme isomers, MaeA and MaeB. qRT-PCR was carried out under malate and pyruvate supplemented conditions to understand the dynamics of maeA and maeB gene expression. maeA expression was elevated by malate, and maeB expression was inhibited by levels of both malate and pyruvate higher than 0.1 mM. Green fluorescent protein (GFP) reporter plasmids were also constructed by integration of the maeA/maeB promoter with the gfp gene. We showed that maeA driven GFP expression was positively and negatively correlated with extracellular malate and pyruvate induction. In contrast, no significant changes in maeB driven GFP expression were observed under both malate and pyruvate supplemented conditions. 相似文献
60.
Polypyrrole (PPy) microstructures with diverse shapes were synthesized in an aqueous inorganic salt medium including organic crystals and pyrrole (Py). A series of sulfobenzoic acid salt forms with various cations (K+, Na+, Li+, NH4+) in different positions (para, meta, ortho) of the sulfonate group on the benzene ring were used to form organic crystals as sacrificial templates. Using these crystals, we produced five different shapes of PPy microstructures (hexagonal microplates, curled nanofibers, lozenge-shaped microplates, rigid rods, parallelogram microplates), which replicated the shapes of the organic crystal templates through electrostatic interaction between the anionic crystal surfaces and the cationic PPy chains. In contrast, PPy that was polymerized without crystals showed bulky agglomerates of 200-500 nm size. The electrical properties were dictated by the molecular structures of the organic salt molecules used. While the highest conductivity (200.3 Scm−1) was observed in PPy using crystals of para-linked 4-sulfobenzoic acid monopotassium salt, the lowest conductivity (0.8 Scm−1) was observed in PPy prepared in the presence of crystals of ortho-linked 2-sulfobenzoic acid monoammonium salt. 相似文献