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91.
Effects of various additives, such as diatomaceous earth, inorganic adsorbent, and polymeric flocculant, on cake filtration
performance were evaluated. By performing the standard vacuum filtration experiments under a constant pressure condition,
we quantified their ability to reduce cake compressibility and to remove fine particulate matters. From the flux decline curves
obtained, we used modified Ruth equation to determine the cake compressibility index. The filtrate clarity was quantified
by measuring its turbidity spectrophotometrically. Diatomaceous earth filter aid was very effective in reducing the compressibility
thereby improving filtrate flux. Calcium phosphate adsorbent was more effective in clarity improvement than in flux enhancement,
whereas an anionic flocculant was effective in both aspects. When these additives were used together, the expected additive,
synergic effect was not realized. However, about 3.5 times higher initial flux and 6-fold improved clarity were obtained as
compared to the control experiment. Experimentally obtained flux decline curves were perfectly fitted into one of the Hermia’s
blocking filtration law equations. Also, it was experimentally observed that the compressibility reduction improved filtrate
clarity in a linear fashion. This type of approach is useful to quantitatively determine each additive’s characteristics and
thus to maximize the performance of cake filtration operations. 相似文献
92.
Jae‐Ho Kim Ho‐Gyum Kim Jeoung‐Cheol Lim Kwang‐Soo Cho Kyung‐Eun Min 《应用聚合物科学杂志》2012,124(4):3312-3319
The thermal stability and adhesion properties, such as lap‐shear strength of hot‐melt adhesives were obtained from amorphous poly(α‐olefins) and thermoplastic rubber [styrene–ethylene–butylene copolymer (SEBS)] blends. The addition of SEBS increased the toughness and viscosity and decreased the lap‐shear strength of the hot‐melt adhesive. Terpene tackifier resin offered enhanced lap‐shear strength; this was more effective when combined tackifier resin was added on the hot‐melt adhesive. Only a small amount of wax and antioxidant affected the thermal stability and lap‐shear strength of the hot‐melt adhesive. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
93.
Duc Quy Vo Eun Woo Shin Jae-Seong Kim Sunwook Kim 《Korean Journal of Chemical Engineering》2012,29(1):120-124
A significant change in the UV-vis absorption of TiO2 nanorods (NRs) was induced by changing electrondonating stabilizer from oleic acid (OA) to acrylic acid (AcA). When TiO2 NRs with an average size of 2.5 nm in diameter and 30 nm in length were dispersed in an aqueous AcA solution, a red shift in the optical absorption (0.73 eV at the band edge and 0.55 eV at the onset) was observed. The red shift was attributed to an increase in the electron density inside the TiO2 NRs. The applicability of the AcA-exchanged TiO2 NRs for the photocatalyst as well as a UV sensor was evaluated. The AcA-exchanged TiO2 NRs showed significant photocatalytic activity on the degradation of toluene in the visible light region. Moreover, thin film of the AcA-exchanged TiO2 NRs on a quartz plate was tested as a UV sensor and it exhibited a good response to a wide range of the UV light. 相似文献
94.
Eun Young Park Yasushi Nakamura Kenji Sato Yasuki Matsumura 《Journal of the American Oil Chemists' Society》2012,89(3):477-484
We investigated the effects of amino acids and peptide on lipid oxidation in emulsion systems. For comparative purposes, we
also tested the antioxidant activity of ferulic acid, a typical phenolic antioxidant. Histidine and cysteine retarded lipid
oxidation (the amount of thiobarbituric acid [TBA]-reactive substances reached approximately 13 and 18 μM after 7 days, respectively),
whereas arginine, methionine, and tryptophan did not inhibit the progression of oxidation. Soy peptide also inhibited lipid
oxidation. Ferulic acid was found to be the most effective suppressor of lipid oxidation (TBA-reactive substances were suppressed
to <3 μM over 7 days). The antioxidant activities of soy peptide and ferulic acid were related to the purity of the emulsifier
used. The radical scavenging activities of soy peptide and ferulic acid were closely related to their inhibitory effects on
lipid oxidation. However, this was not the case for amino acids. Decreases in the turbidity of emulsions were closely related
to increases in TBA values. 相似文献
95.
Tae-Jun Ko Eun Kyu Her Bongsu Shin Ho-Young Kim Kwang-Ryeol Lee Bo Ki Hong Sae Hoon Kim Kyu Hwan Oh Myoung-Woon Moon 《Carbon》2012,50(14):5085-5092
We have explored the condensation behavior of water on a superhydrophobic carbon fiber (CF) network with high-aspect-ratio hair-like nanostructures. Nanostructures ranging from nanopillars to hairy shapes were grown on CFs by preferential oxygen plasma etching. Superhydrophobic CF surfaces were achieved by application of a hydrophobic siloxane-based hydrocarbon coating, which increased the water contact angle from 147° to 163° and decreased the contact angle hysteresis from 71° to below 5°, sufficient to cause droplet roll-off from the surface. Water droplet nucleation and growth on the superhydrophobic CF were significantly retarded due to the high-aspect-ratio nanostructures under super-saturated vapor conditions. CFs are observed to wet with condensation between fibers of the pristine surface under super-saturated vapor conditions, which eventually leads to flooding. However, dropwise condensation became dominant in the superhydrophobic CF network, allowing for easy removal of the condensed droplets, which largely allowed the interstitial spaces of the fiber network to remain dry. It is implied that superhydrophobic CF can provide a passage for vapor or gas flow in wet environments such as a gas diffusion layer requiring the effective water removal in the operation of proton exchange membrane fuel cell. 相似文献
96.
Sung Bong Kim Sang Jun Lee Eun Ji Jang Sung Ok Han Chulhwan Park Seung Wook Kim 《Journal of Industrial and Engineering Chemistry》2012,18(1):183-187
Rice straw was pretreated with dilute sulfuric acid in order to decrease the amorphous portion and enhance enzyme accessibility. Dilute acid pretreatment process was optimized using a statistical method, and the relationships between each factor were investigated. Saccharification of pretreated rice straw was then performed, followed by fermentation of glucose, the hydrolysate of the saccharification process. The optimal dilute acid pretreatment process was as follows: temperature 110 °C, reaction time 14.02 min, and acid concentration 1.2%. Following dilute acid pretreatment, the solid weight was decreased by about 20% and 73.14% of the theoretical maximum content of xylose was solubilized. Glucose was recovered at a rate of about 90% at 24 h after rice straw was treated with dilute acid. Qualitative analysis such as SEM, XRD, and FT-IR were conducted after the pretreatment process, and the results supported the pretreatment process. 相似文献
97.
Chun Dong Hyun Rhim Geun Bae Youn Min Hye Deviana Deviana Lee Ji Eun Park Ji Chan Jeong Heondo 《Topics in Catalysis》2020,63(9-10):793-809
Topics in Catalysis - Fischer–Tropsch synthesis (FTS) is a promising way to produce clean liquid fuels and high value-added chemicals from low-value carbon-containing resources such as coal,... 相似文献
98.
To improve the electrical conductivity of polyacrylonitrile (PAN) film, metallic sulfides and PAN composite film were prepared by the chelating method. Dense PAN film and porous PAN film were prepared by dry process and wet process, respectively. These PAN films were treated to NH2OH solution to introduce the amidoxime group coordinated with metallic ion. Cu+2 and Cd+2 ions were adsorbed to amidoximated PAN films, the sulfur ion was treated with metal-adsorbed PAN films, and thus CuS—and CdS–PAN composite films were prepared. The adsorptive capacity of amidoximated PAN film for the Cu+2 ion was independent of the morphology of the PAN film, but the adsorptive capacity of the Cd+2 ion on amidoximated PAN film was dependent on porosity of the polymer. Adsorptive capacity of amidoximated porous PAN film for Cd+2 was improved about four times than that of amidoximated dense PAN film. The electrical conductivities of CuS–dense and porous PAN composite film were both 10?1 S/cm in optimum condition, but because of the difference in adsorptive capacity, the electrical conductivities of CdS–dense and CdS–porous PAN composite films were 10?9 S/cm and 10?4 S/cm, respectively. Additionally, because CdS was known as a photoconductive material, the photoconductive properties of CdS–porous PAN composite film were investigated. 相似文献
99.
Unsaturated polyester (UP)/montmorillonite (MMT) nanocomposite was prepared by using hydroxypropylacrylate (HPA) as a reactive diluent instead of conventional styrene monomer and the effect of polarity of reactive diluent on properties of nanocomposite was investigated. X‐ray and mechanical test data indicated that mixing for an extended period of time is essential to enhance the physical properties of nanocomposites in the UP/Cloisite 6A system. This was attributed to the high polarity of HPA that may disturb the preintercalation of UP resin into the galleries of MMT. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 238–242, 2004 相似文献
100.
Formation and Accumulation of Intragranular Pores in the Hydrothermally Synthesized Barium Titanate Nanoparticles 下载免费PDF全文
Changyeon Baek Ji Eun Wang San Moon Chang‐Hak Choi Do Kyung Kim 《Journal of the American Ceramic Society》2016,99(11):3802-3808
As highly integrated circuits are demanded for high‐performance electric devices, small sizes of barium titanate (BaTiO3) as a dielectric material are desirable for the application of multilayer ceramic capacitors. Since the small sizes of the particles degrade the dielectric property, especially below a certain critical size, understanding the probable cause is significant for the high‐performance capacitors. Here, we have demonstrated nanosized BaTiO3 with average size below 30 nm and a uniform size distribution. High‐resolution transmission electron microscopy (TEM) shows that the as‐synthesized BaTiO3 contains intragranular pores. We have analyzed the correlation between the intragranular pores inside nanoparticles and their phase ratio of cubic and tetragonal. We have found that the presence of the intragranular pores affects low tetragonality of BaTiO3 particles, and the intragranular pores are generated by the accumulation of hydroxyl groups during hydrothermal reaction. Formation and accumulation of intragranular pores have been investigated by ex‐situ synchrotron X‐ray diffraction and TEM analysis, suggesting the phase evolution model of nanosized BaTiO3. 相似文献