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21.
The modeling of particle aggregation under a simple shear flow and the extension of the model to a stirred vessel is described. The model quantitatively demonstrates the change of the number of aggregates with time for each shear rate. This number increased with higher shear rate and, conversely, the aggregate size became small when raising the shear rate. This was because aggregates were broken by the stronger shear force. The number of aggregates for different impellers was determined. The shear rate was back‐calculated from the experimentally obtained aggregate size and the model equation. This shear rate was different from that estimated from the Metzner‐Otto method, consequently, some revisions of the Metzner‐Otto equation might be necessary for its application to particle aggregation. 相似文献
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Yuta Fujita Akihiro Ametani Keisuke Nakamura Koichi Yamabuki 《Electrical Engineering in Japan》2014,188(1):36-45
This paper investigates the mutual grounding impedance between vertical grounding electrodes based on field measurements and FDTD simulations. In the case of vertical electrodes, the mutual impedance between the electrodes is almost completely independent of the electrode length, and thus the induced voltage is nearly constant as the electrode length becomes longer. This characteristic is different from that of an overhead conductor, where the electromagnetic‐induced voltage is proportional to the conductor length. The greater the separation distance between the electrodes, the smaller the induced voltage, as in the case of an overhead conductor. The propagation speed increases as the separation increases. It is found that the speed is not necessarily proportional to the inverse of the relative permittivity of the earth. 相似文献
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To understand the adsorption properties of a styrene–divinylbenzene copolymer functionalized with N,N,N-trimethylglycine, AMP03, the adsorption behaviours for platinoid ions (Ru(III), Rh(III) and Pd(II)) were examined. Furthermore, we performed adsorption experiments using sample solutions by adding triethylamine, thiourea and N,N,N-trimethylglycine. Based on the adsorption data obtained in this study, we performed chromatographic experiments. The results indicated that all platinoid ions in the feed solution completely adsorbed on AMP03, and almost 80% of the adsorbed platinoid ions were recovered. These results show that AMP03 has the potential to recover Ru(III), Rh(III) and Pd(II) from high-level liquid waste. 相似文献
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Ozonation and four types of advanced oxidation processes, including O3/H2O2, O3/UV, O3/H2O2/UV, and UV/H2O2, were evaluated for the treatment of contaminated groundwater at a Superfund site in Simpsonville, South Carolina using bench-scale, batch ozone and UV apparatuses. Although the contaminants of concern were 1,4-dioxane, 1,1-dichloroethene, and trichloroethene, several other chlorinated organics as well as tetrahydrofuran were found in the groundwater samples. The O3/H2O2 treatment with O3 and H2O2 doses of 6 and 1.5 mg/L, respectively, and the UV/H2O2 treatment with UV and H2O2 doses of 1,000 mJ/cm and 20 mg/L, respectively, were sufficient to degrade 200 µg/L of 1,4-dioxane, 110 µg/L of 1,1-dichloroethene, and 10 µg/L of trichloroethene below their performance standards of 10, 7, and 4 µg/L, respectively. Due to a high bromide concentration (0.35 mg/L) in the groundwater sample, bromate formation was found to be significant in ozone-based treatment, including O3/H2O2. 相似文献
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Back Cover: Tailored Synthesis of 162‐Residue S‐Monoglycosylated GM2‐Activator Protein (GM2AP) Analogues that Allows Facile Access to a Protein Library (ChemBioChem 20/2016) 下载免费PDF全文
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Keisuke Yotsuji Naoyuki Hoshiya Takaaki Kobayashi Hayato Fukuda Hiroshi Abe Mitsuhiro Arisawa Satoshi Shuto 《Advanced Synthesis \u0026amp; Catalysis》2015,357(5):1022-1028
We describe a nickel‐catalyzed Suzuki–Miyaura arylation of a tertiary iodocyclopropane with arylboronic acids; this is an efficient and convergent strategy for providing various enantioenriched arylcyclopropanes with a quaternary stereogenic center. This is the first metal‐catalyzed coupling between a tertiary alkyl electrophile and a wide range of aromatics, including heteroaromatics. We found that the outcome of the Ni‐catalyzed coupling with halides as electrophiles was dependent on the stability of the radical species formed during the reaction. The use of tert‐butyl alcohol (t‐BuOH) as the reaction solvent was very effective, because of its stability under the radical‐generating reaction conditions.