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81.
E. E. Son I. F. Suvorov S. V. Kakurov Al. F. Gaisin G. T. Samitova T. L. Solov’eva A. S. Yudin T. V. Rakhletsova 《High Temperature》2014,52(4):490-496
The results of experimental investigation of the DC electrical discharge with moving air bubbles in the electrolyte, as well as of high frequency electrical discharge with a diaphragm membrane, within a wide parameter range are presented. We investigated active component formation and enhancement of the wastewater decontamination by means of production of a disinfecting agent with a maximal content of the electrical discharge products (copper and silver ions and hydrogen peroxide). 相似文献
82.
Sang-Hoon Song Ju-Hee Son Anatta Wahyu Budiman Myoung-Jae Choi Tae-Sun Chang Chae-Ho Shin 《Korean Journal of Chemical Engineering》2014,31(2):224-229
The carbon dioxide dry reforming of methane (CDR) reaction could be thermodynamically favored in the range of 800 to 1,000 °C. However, the catalyst in this reaction should be avoided at the calcination temperature over 800 °C since strong metal support interaction (SMSI) in this temperature range can decrease activity due to loss of active sites. Therefore, we focused on optimizing the temperature of pretreatment and a comparison of surface characterization results for CDR. Results related to metal sintering over support, re-dispersion by changing of particle size of metal-support, and strong metal support interaction were observed and confirmed in this work. In our conclusion, optimum calcination temperature for a preparation of catalyst was proposed that 400 °C showed a higher and more stable catalytic activity without changing of support characteristics. 相似文献
83.
A Highly Planar Fluorinated Benzothiadiazole‐Based Conjugated Polymer for High‐Performance Organic Thin‐Film Transistors 下载免费PDF全文
84.
Effect of Sintering Temperature on Thermoelectric Properties of p‐Bi2Te3 Alloys Produced by Gas Atomization 下载免费PDF全文
Babu Madavali Hyo‐Seob Kim Min‐Gyu Choi Gi‐Chan Park Jar‐Myung Koo Hyeon‐Taek Son Soon‐Jik Hong 《International Journal of Applied Ceramic Technology》2016,13(2):245-251
In this research, p‐type Bi2Te3–75% Sb2Te3 thermoelectric alloy powders were produced by gas atomization and subsequently sintered by hot pressing at different temperatures. The grain growth of the hot‐pressed samples was observed with increasing sintering temperature from 380°C to 460°C. The compressive strength increased with increasing hot‐pressing temperature due to the high relative density of bulk samples obtained at high temperatures. The effect of sintering temperature on thermoelectric (TE) properties was studied. The maximum power factor 3.48 mW/mK2 was obtained for the sample hot pressed at 420°C due to the resulting high electrical conductivity and enhanced Seebeck coefficient values. 相似文献
85.
Preparation and characterization of composite gels and films containing gelatin and hydroxypropyl methylcellulose phthalate 下载免费PDF全文
Composite gels and films were prepared by the blending of hydrated gelatin as a base material and hydroxypropyl methylcellulose phthalate (HPMCP) at various mass ratios. A composite technology was applied to obtain improved mechanical, physicochemical, and antimicrobial properties of the gelatin used as a base material. We investigated the effects of different experimental conditions on the rheological and mechanical properties and antimicrobial activities of the composite gels, films, and solutions. The rheological values (storage modulus, loss modulus, and complex viscosity) of the composite solutions and gels increased with added HPMCP. Aerobic microorganisms, yeasts, and molds were not detected throughout the testing period in the gelatin–HPMCP composite solution. In contrast, many microorganisms were detected in the gelatin‐only samples beginning with day 3 of storage. The composite films exhibited relatively good mechanical and physical properties compared with the gelatin‐only film. The composite film containing HPMCP at a mass ratio greater than 1:4 did not dissolve in gastric juice (pH 1.2) for at least 2 h, but all other samples, including the gelatin‐only film dissolved in enteric juice (pH 6.8). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39597. 相似文献
86.
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.
87.
Maleated poly(lactic acid) (PLA-g-MA) was prepared through melt grafting of maleic anhydride onto a PLA backbone with the aid of a radical initiator. PLA-g-MA thus formed was incorporated into PLA/polyamide 11 (PA11) blends as a reactive compatibilizer. By morphological observation, it was assessed that PLA-g-MA lowered the interfacial energy and strengthened the interface between PLA and PA11. However, the compatibilized PLA/PA11 blends did not show significant improvement of impact strength compared with noncompatibilized PLA/PA11 blends. Measurements of the molecular weight and impact strength of PLAs compounded with various amounts of radical initiators revealed that decreased molecular weight of PLA by the radical initiator used for the preparation of PLA-g-MA is responsible for this unexpected result. To compensate the decrease of the molecular weight, a crosslinking agent was incorporated in the preparation step of PLA-g-MA. It was found that the crosslinking agent is effective in preventing the molecular weight reduction. As a result, the impact strength of the PLA/PA11 blend was enhanced to a great extent by the PLA-g-MA prepared with the crosslinking agent. 相似文献
88.
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
89.
Won-Jun Jang Taekwon Son Sang-Hoon Song In Soo Ryu Sooyeun Lee Chul-Ho Jeong 《International journal of molecular sciences》2020,21(22)
Methamphetamine (MA) use disorder is a chronic neuropsychiatric disease characterized by recurrent binge episodes, intervals of abstinence, and relapses to MA use. Therefore, identification of the key genes and pathways involved is important for improving the diagnosis and treatment of this disorder. In this study, high-throughput RNA sequencing was performed to find the key genes and examine the comparability of gene expression between whisker follicles and the striatum of rats following MA self-administration. A total of 253 and 87 differentially expressed genes (DEGs) were identified in whisker follicles and the striatum, respectively. Multivariate and network analyses were performed on these DEGs to find hub genes and key pathways within the constructed network. A total of 129 and 49 genes were finally selected from the DEG sets of whisker follicles and of the striatum. Statistically significant DEGs were found to belong to the classes of genes involved in nicotine addiction, cocaine addiction, and amphetamine addiction in the striatum as well as in Parkinson’s, Huntington’s, and Alzheimer’s diseases in whisker follicles. Of note, several genes and pathways including retrograde endocannabinoid signaling and the synaptic vesicle cycle pathway were common between the two tissues. Therefore, this study provides the first data on gene expression levels in whisker follicles and in the striatum in relation to MA reward and thereby may accelerate the research on the whisker follicle as an alternative source of biomarkers for the diagnosis of MA use disorder. 相似文献
90.
Mina Han Ikue Abe Jihun Oh Jaehoon Jung Young Ji Son Jaegeun Noh Mitsuo Hara Takahiro Seki 《International journal of molecular sciences》2022,23(2)
Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H2O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials. 相似文献