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101.
102.
Sun-Ae Moon Tae-Gu Lee Jin-Huek Hur Ki-Moo Heo Hoseon Yoo Seung-Jae Moon Jae-Heon Lee 《Heat and Mass Transfer》2008,44(11):1345-1353
In this paper, the averaged reentering rates of the densely built cooling towers, which form banks on the building roof in
Seoul, Korea have been predicted by a numerical method according to various summer wind conditions and roof wall types. The
averaged reentering rates of all the cooling towers are compared according to two wall types to study the effect of the intake
outdoor air louver on the reentering rates. Consequently, two findings are drawn as follows. (1) With a curtain wall, the
averaged reentering rates of the total cooling towers against the west and the south wind at ν = 5 m/s are 13.3 and 24.4%, respectively. Therefore, it is strongly needed to find a method to reduce the reentering of the
discharged air from the cooling towers. (2) In the case of a louver wall, the averaged reentering rates of the cooling towers
with the west and south wind at ν = 5 m/s are 2.5 and 9.74%, respectively, which have been estimated to be lower than those of the curtain wall. Therefore,
the louver wall can be suitably adopted to reduce the reentering of the discharged air from the cooling towers in the present
study. 相似文献
103.
B.S. Kang S. Kim F. Ren K. Ip Y.W. Heo B.P. Gila C.R. Abernathy D.P. Norton S.J. Pearton 《Applied Physics A: Materials Science & Processing》2005,80(2):259-261
Bulk Pt/ZnO Schottky rectifiers show gas sensitivities for CO of 4% and 8%, respectively, at 150 °C for 1 and 10% CO in N2. The current or voltage changes are time dependent, with an activation energy of 40.7 kJmol-1. Over a limited range of partial pressures of CO (PCO) in the ambient gas, the on-state resistance R of the sensor at fixed bias voltage decreased according to R=(RO+A(PCO)0.5)-1, where A is a constant and RO is the resistance in N2. Since these devices are also sensitive to H2 and C2H4, the ZnO rectifiers appear promising for a range of gas-sensing applications. PACS 81.05.Dz; 73.61.Ga; 72.80.Ey 相似文献
104.
Geetha Thiagarajan Effendi Widjaja Jun Hyuk Heo Jason K. Cheung Busolo Wabuyele Xiaodun Mou Mohammed Shameem 《Journal of Raman spectroscopy : JRS》2015,46(6):531-536
Structural complexity of biological drug products presents an analytical challenge in terms of early detection of aggregation and/or degradation. In the present study, Raman and Raman optical activity (ROA) were evaluated for their sensitivity to detect heat‐induced molecular instability in an Immunoglobulin G4 subclass therapeutic monoclonal antibody present in its formulation matrix. The therapeutic antibody was subjected to heat stress at 50 °C and was analyzed at various time points up to 1 month. The current results suggest that Raman and ROA are sensitive to early‐stage detection of heat‐induced instability of the antibody, in which significant changes could be observed at 1 week of stress. ROA could provide early detection of the subtle differences at the tertiary structure level in a heat‐stressed monoclonal antibody and Raman/ROA spectra could provide early detection in secondary structural changes as well. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
105.
Effect of sorbitol doping in PEDOT:PSS on the electrical performance of organic photovoltaic devices
Organic photovoltaic cells have important advantages, such as low cost and mechanical flexibility. The conducting polymer poly(3,4 ethylenedioxy-thiophene):poly(styrene sulfonate) (PEDOT:PSS) has been widely used as an interfacial layer or a polymer electrode in polymer electronic devices, such as photovoltaic devices and light-emitting diodes. In this report, we discuss the direct current (DC) conductivity of PEDOT:PSS films containing various weight ratios of sorbitol dopant. The work function is shown to steadily decrease with increasing dopant content. With different dopant contents, illuminated current–voltage photovoltaic characteristics were observed. Ultraviolet photoelectron spectroscopy (UPS) analysis revealed that the work function of the PEDOT:PSS was affected by its sorbitol content. The morphologies of the doped PEDOT:PSS films were characterized by atomic force microscopy (AFM). For the device fabrication, we made organic photovoltaic cells by a spin-coating process and Al deposition by thermal evaporation. The sorbitol dopant is able to improve the efficiency of the device. 相似文献
106.
Das A Heo J Jankowski M Guo W Zhang L Deng H Bhattacharya P 《Physical review letters》2011,107(6):066405
We report ultralow threshold polariton lasing from a single GaN nanowire strongly coupled to a large-area dielectric microcavity. The threshold carrier density is 3 orders of magnitude lower than that of photon lasing observed in the same device, and 2 orders of magnitude lower than any existing room-temperature polariton devices. Spectral, polarization, and coherence properties of the emission were measured to confirm polariton lasing. 相似文献
107.
Min Yeong Park Sang Eun Ha Hun Hwan Kim Pritam Bhagwan Bhosale Abuyaseer Abusaliya Se Hyo Jeong Joon-Suk Park Jeong Doo Heo Gon Sup Kim 《Molecules (Basel, Switzerland)》2022,27(12)
Inflammation is a severe topic in the immune system and play a role as pro-inflammatory mediators. In response to such inflammatory substances, immune cells release cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). Lipopolysaccharide (LPS) is known as an endotoxin in the outer membrane of Gram-negative bacteria, and it catalyzes inflammation by stimulating the secretion of inflammatory-mediated cytokines such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by stimulated immune cells. Among the pathways involved in inflammation, nuclear factor kappa (NF-кB) and mitogen-activated protein kinases (MAPKs) are important. NF-kB is a diploid composed of p65 and IkBα and stimulates the pro- gene. MAPKs is a family consisting of the extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38, JNK and p38 play a role as proinflammatory mediators. Thus, we aim to determine the scutellarein (SCU) effect on LPS stimulated RAW264.7 cells. Furthermore, since scutellarein has been shown to inhibit the SARS coronavirus helicase and has been used in Chinese medicine to treat inflammatory disorders like COVID-19, it would be required to examine scutellarein’s anti-inflammatory mechanism. We identified inflammation-inducing substances using western blot with RAW264.7 cells and SCU. And we discovered that was reduced by treatment with SCU in p-p65 and p-IκBα. Also, we found that p-JNK and p-ERK were also decreased but there was no effect in p-p38. In addition, we have confirmed that the iNOS was also decreased after treatment but there is no change in the expression of COX-2. Therefore, this study shows that SCU can be used as a compound to treat inflammation. 相似文献
108.
Agusbudiman Agung Lee Kyoung Beom Lee Jong Man Hwang Sang Hoon Heo Dong Hye 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):539-550
Journal of Radioanalytical and Nuclear Chemistry - The sheared granite of El Sela represents one of the most promising uranium mineralization in the southern part of the eastern desert, in Egypt.... 相似文献
109.
Gwang-Sik Song Youn-Jung Heo Jeong Ju Baek Hyosun Lee Geun Yeol Bae Kyung Ho Choi Won-Gun Koh Gyojic Shin 《Journal of polymer science. Part A, Polymer chemistry》2021,59(4):340-352
In this article, photosensitive polyimides (PSPIs) with photosensitive groups, o-nitrobenzyl ether groups (Nb), were successfully synthesized based on 2,2′-dihydroxy benzophenone-3,3′,4,4′-tetracarboxylic dianhydride and on diamine containing ethylene glycol chains (ODA). Also, a series of polyimide (PI), ODA-1-PI, ODA-3-PI, and ODA-5-PI with a number of ethylene glycol chains of 1, 3, and 5 were prepared to investigate the relationship between structure and solubility. Interestingly, ODA-5-PI, which possesses a large number of ethylene glycols, exhibited the most excellent solubility. Therefore, due to the good solubility of ODA-5-PI in organic solvents and alkaline solutions, a PSPI, poly(1,4-phenyleneoxy-3,6,9,12,15-pentaoxaoctane-1,4-phenylene-2,2′-di[2-nitrobenzyloxy]benzophenone-3,3′,4,4′-tetracarboxdiimide), named ODA-5-PSPI, was synthesized by linking Nb, which is a photosensitive group. Aiming at producing positive tone patterns, the synthesized ODA-5-PSPI was exposed to UV irradiation and then to a post-exposure bake. Afterward, it was developed using a 2.38 wt% tetramethylammonium hydroxide solution. Furthermore, a photoacid generator (PAG) was additionally incorporated for a micropatterning process. Notably, in the presence of the PAG, the photocleavage of ODA-5-PSPI occurred not only by the intramolecular rearrangement of Nb but also by its hydrolysis reaction. As a result, due to the synergistic effect of photocleavage, the micropatterning of ODA-5-PSPI with PAG could be clearly obtained with less energy (2.0 J/cm2) compared with that without PAG (3.6 J/cm2). Therefore, through the addition of PAG, the photosensitivity was improved by 45%. 相似文献
110.
Free solution capillary electrophoresis of proteins using untreated fused-silica capillaries. 总被引:2,自引:0,他引:2
Numerous efforts have been made to separate proteins by capillary zone electrophoresis (CZE). The most common optimization techniques are changing the pH of the running buffer, coating the capillary surface with a hydrophilic polymer, or using additives in the sample solution. Surface coatings and solution additives can reduce the adsorption of the protein onto the capillary surface, but they diminish the separation efficiency and the resolution of CZE. This paper reports the successful separation of proteins in a untreated fused-silica capillary by raising the pH of the running buffer and washing between runs with 1.0 M sodium hydroxide. Under these conditions, model proteins and proteins in human serum have been determined by CZE. It is shown that the results from CZE are compatible with those of sodium dodecyl sulphate-polyacrylamide gel electrophoresis. 相似文献