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101.
To apply sericite effectively in the adsorption process, it was immobilized by entrapment method using sodium alginate. Since the immobilized sericite beads have excellent mechanical strength and swelling characteristics, channeling of flow and the increase of pressure drop were not observed through column operations. In addition, it was also stable under pH 10 and 45 °C of cesium solution. The maximum adsorption capacity and Langmuir adsorption constant was 1.430mg/g and 2.329 L/mg, respectively, at initial pH 5 of cesium solution in batch type and the Langmuir model with higher correlation coefficient of 0.997 fits experimental data better than Freundlich model. The breakthrough point emerged around 15 (1.0 mL/min) and 20 bed volumes (0.5 mL/min), and the cesium ions bound to the immobilized sericite beads were readily released and quantitatively recovered by a few bed volumes of 1.0M of HNO3 solution. Furthermore, bed volumes of cesium ions for firstly reused sericite beads can be still maintained as 18, which shows good regeneration ability. 相似文献
102.
Woo Hyung Jeon Jeong‐Yu Son Sun‐Eung Kim Phil Ho Lee 《Advanced Synthesis \u0026amp; Catalysis》2015,357(4):811-817
An efficient phosphaannulation via palladium(II)‐catalyzed C H activation/oxidative cyclization by the 6‐endo mode is reported for the synthesis of 3‐substituted phosphaisocoumarins from the reaction of arylphosphonic acids with unactivated alkenes under aerobic conditions. Also, α,α‐disubstituted benzylphosphonic acids were phosphaannulated with unactivated alkenes, producing phosphaisochromanones having (Z)‐alkylidenyl groups via anti‐phosphoryloxypalladation by the 6‐exo mode.
103.
104.
Dae Gyu Kwon Myung Ku Kim Yoon Sang Jeon Yoon Cheol Nam Jin Seong Park Dong Jin Ryu 《International journal of molecular sciences》2022,23(3)
Osteoarthritis (OA) has generally been introduced as a degenerative disease; however, it has recently been understood as a low-grade chronic inflammatory process that could promote symptoms and accelerate the progression of OA. Current treatment strategies, including corticosteroid injections, have no impact on the OA disease progression. Mesenchymal stem cells (MSCs) based therapy seem to be in the spotlight as a disease-modifying treatment because this strategy provides enlarged anti-inflammatory and chondroprotective effects. Currently, bone marrow, adipose derived, synovium-derived, and Wharton’s jelly-derived MSCs are the most widely used types of MSCs in the cartilage engineering. MSCs exert immunomodulatory, immunosuppressive, antiapoptotic, and chondrogenic effects mainly by paracrine effect. Because MSCs disappear from the tissue quickly after administration, recently, MSCs-derived exosomes received the focus for the next-generation treatment strategy for OA. MSCs-derived exosomes contain a variety of miRNAs. Exosomal miRNAs have a critical role in cartilage regeneration by immunomodulatory function such as promoting chondrocyte proliferation, matrix secretion, and subsiding inflammation. In the future, a personalized exosome can be packaged with ideal miRNA and proteins for chondrogenesis by enriching techniques. In addition, the target specific exosomes could be a gamechanger for OA. However, we should consider the off-target side effects due to multiple gene targets of miRNA. 相似文献
105.
Robert F. DeJaco Matheus Dorneles de Mello Huong Giang T. Nguyen Mi Young Jeon Roger D. van Zee Michael Tsapatsis Joern Ilja Siepmann 《American Institute of Chemical Engineers》2020,66(4):e16868
In this work, batch-adsorption experiments and molecular simulations are employed to probe the adsorption of binary mixtures containing ethanol or a linear alkane-1,n-diol solvated in water or ethanol onto silicalite-1. Since the batch-adsorption experiments require an additional relationship to determine the amount of solute (and solvent) adsorbed, as only the bulk liquid reservoir can be probed directly, molecular simulations are used to provide a relationship between solute and solvent adsorption for input to the experimental bulk measurements. The combination of bulk experimental measurements and simulated solute–solvent relationship yields solvent and solute loadings that are self-consistent with simulation alone, and allow for an assessment of the various assumptions made in the literature. At low solution concentrations, the solute loading calculated is independent of the assumption made. At high concentrations, a negligent choice of assumption can lead to systematic overestimation or underestimation of calculated solute loading. 相似文献
106.
Jae-Sung Kim Seok-Jun Mun Euni Cho Donggyu Kim Wooic Son Hye-In Jeon Hyo Keun Kim Kiseok Jang Chul-Su Yang 《International journal of molecular sciences》2020,21(22)
Dense granule proteins (GRAs) are essential components in Toxoplasma gondii, which are suggested to be promising serodiagnostic markers in toxoplasmosis. In this study, we investigated the function of GRA9 in host response and the associated regulatory mechanism, which were unknown. We found that GRA9 interacts with NLR family pyrin domain containing 3 (NLRP3) involved in inflammation by forming the NLRP3 inflammasome. The C-terminal of GRA9 (GRA9C) is essential for GRA9–NLRP3 interaction by disrupting the NLRP3 inflammasome through blocking the binding of apoptotic speck-containing (ASC)-NLRP3. Notably, Q200 of GRA9C is essential for the interaction of NLRP3 and blocking the conjugation of ASC. Recombinant GRA9C (rGRA9C) showed an anti-inflammatory effect and the elimination of bacteria by converting M1 to M2 macrophages. In vivo, rGRA9C increased the anti-inflammatory and bactericidal effects and subsequent anti-septic activity in CLP- and E. coli- or P. aeruginosa-induced sepsis model mice by increasing M2 polarization. Taken together, our findings defined a role of T. gondii GRA9 associated with NLRP3 in host macrophages, suggesting its potential as a new candidate therapeutic agent for sepsis. 相似文献
107.
Hyun Ju Park Young-Kwon Park Jong-In Dong Joo-Sik Kim Jong-Ki Jeon Seung-Soo Kim Jinsoo Kim Byungho Song Junhong Park Kyung-Jin Lee 《Fuel Processing Technology》2009
The kinetic parameters for the pyrolysis of Oriental white oak were evaluated by thermogravimetric analysis (TGA). The white oak was pyrolyzed in a fluidized bed reactor with a two-staged char separation system under a variety of operating conditions. The influence of the pyrolysis conditions on the chemical and physical characteristics of the bio-oil was also examined. TGA showed that the Oriental white oak decomposed at temperatures ranging from 250 to 400 °C. The apparent activation energy ranged from 160 to 777 kJ mol− 1. The optimal pyrolysis temperature for the production of bio-oil in the fluidized bed unit was between 400 and 450 °C. A much smaller and larger feed size adversely affected the production of bio-oil. A higher fluidizing gas flow and higher biomass feeding rate were more effective in the production of bio-oil but the above flow rates did not affect the bio-oil yields significantly. Recycling a part of the product gas as a fluidizing medium resulted the highest bio-oil yield of 60 wt.%. In addition, high-quality bio-oil with a low solid content was produced using a hot filter as well as a cyclone. With exception of the pyrolysis temperature, the other pyrolysis conditions did not significantly affect the chemical and physical characteristics of the resulting bio-oil. 相似文献
108.
Thermal hydraulic performance analysis of the printed circuit heat exchanger using a helium test facility and CFD simulations 总被引:2,自引:0,他引:2
In Hun Kim Hee Cheon No Jeong Ik Lee Byong Guk Jeon 《Nuclear Engineering and Design》2009,239(11):2399-2408
The thermal-hydraulic performance of the PCHE was investigated using the KAIST helium test loop. Experiments were performed in the helium laminar region with 350 < Re < 1200. The hot/cold side inlet conditions were 25–550 °C/25–100 °C over the operating pressure of 1.5–1.9 MPa, respectively. Mass flow rates were controlled in the range of 40–100 kg/h. Pressure drop and temperature difference were measured at the inlet and outlet of the hot and cold sides. A global Fanning factor correlation and a global Nusselt number correlation were proposed using information only at the inlet and outlet of the hot and cold sides. A three-dimensional (3-D) numerical simulation was performed using FLUENT, a commercial computational fluid dynamics (CFD) code, to compare simulation results to the KAIST helium test data and to obtain the local Nusselt number in the PCHE. CFD predictions showed good agreement with experimental data. A local pitch-averaged Nusselt number correlation was proposed using local temperature, pressure, surface heat fluxes, and properties provided by CFD simulations. The system analysis code, GAMMA, was also utilized to identify which correlation was more applicable for system analysis. It turns out that the proposed local pitch-averaged Nusselt number correlation from CFD simulations is more appropriate than the global Nusselt number correlation developed from experimental data. 相似文献
109.
Hyunwoo Kim Younghoon You Dongkyu Kang Dasom Jeon Sanghyun Bae Yoonkyung Shin Joonseok Lee Jiseok Lee Jungki Ryu 《Advanced functional materials》2019,29(51)
The design and fabrication of solar‐to‐chemical energy conversion devices are enabled through interweaving multiple components with various morphologies and unique functions using a versatile layer‐by‐layer assembly method. Cationic and anionic polyelectrolytes are used as an electrostatic adhesive to assemble the following functional materials: plasmonic Ag nanoparticles for improved light harvesting, upconversion nanoparticles for utilization of near‐infrared light, and polyoxometalate water oxidation catalysts for enhanced catalytic activity. Polyelectrolytes also have an additional function of passivating the surface recombination centers of the underlying photoelectrode. These functional components are precisely assembled on a model photoanode (e.g., Fe2O3 and BiVO4) in a desired order and various combinations without degradation of their intrinsic properties. As a result, the performance of water oxidation photoanodes is synergistically enhanced. This study can enable the design and fabrication of novel solar‐to‐chemical energy conversion devices. 相似文献
110.
Young-Sang Jeon Jukyung Cha Sangwook Nam 《Microwave Theory and Techniques》2007,55(4):690-696
A novel bias-switching scheme for a high-efficiency power amplifier is proposed. Two voltage levels for the drain bias of the RF power amplifier are generated using a combination of a class E dc/ac inverter and a class E rectifier with offset voltage. When signal peaks occur, the output of the class E dc/ac inverter is rectified and the rectified dc is added to the offset voltage by the class E rectifier, which boosts the drain bias of the RF power amplifier. Except during peaks, the drain bias of the RF power amplifier is connected to the offset voltage directly. Since the efficiency when there are no peaks is very high due to the direct connection between the offset voltage and drain bias, the overall efficiency of the RF power amplifier can be improved dramatically in high peak-to-average power ratio (PAPR) systems. The measured results show that the drain bias of the RF power amplifier is boosted up to approximately 1.8 times the offset voltage when the RF peaks generate. The overall efficiency of the proposed bias-switching amplifier is improved by 62% compared to that of the fixed bias amplifier in high PAPR systems 相似文献