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141.
Hirotaka Fujita Qingrong Qian Takao Fujii Kazuhiro Mochizuki Akiyoshi Sakoda 《Adsorption》2011,17(5):869-879
A novel bioethanol separation process was proposed in this study employing molecular sieving carbon (MSC) as an adsorbent,
whose pore diameter is close to molecular size of ethanol. In the proposed process, fermentation broth is first introduced
to the adsorption bed packed with MSC. In this step, ethanol is selectively adsorbed onto MSC, with highly enriching ethanol
in the micropore of MSC. Subsequently, the concentrated ethanol is desorbed from MSC to gaseous phase, resulting in further
purification of ethanol owing to a considerable difference in desorption rate between water and ethanol; Because of molecular
sieving effect of MSC, the desorption rate of ethanol is much smaller than that of water. To establish this process, adsorption
equilibrium and kinetics of ethanol on various MSCs were investigated in aqueous phase as the first step. Also, desorption
kinetics of ethanol and water in gaseous phase were investigated. As a result, it was suggested that highly concentrated ethanol
could be obtained with high recovery ratio through these simple operations, meaning the proposed process is quite promising. 相似文献
142.
Katsumi Katoh Shunsuke Ito Yusuke Wada Eiko Higashi Yasuhiro Suzuki Kazuhiro Kubota Katsuyuki Nakano Yuji Wada 《The Journal of chemical thermodynamics》2011,43(8):1229-1234
In this study, we examined the reaction hazard during the hydrosilylation reaction between trichlorosilane (TCS) and 1,6-divinyl(perfluorohexane) (FDV) in the presence of a butanol solution of chloroplatinic acid (Pt-Cat) as the catalyst. Assuming the three industrial risks of excessive addition of Pt-Cat, contamination by iron rust and mixing with cooling water, we observed the temperature and pressure change of TCS/FDV with an excessive amount of Pt-Cat, TCS/FDV/Pt-Cat with Fe2O3 and TCS/FDV/Pt-Cat with distilled water, using an accelerating rate calorimeter (ARC). The temperature and pressure greatly increased, especially in the sample with Fe2O3. For instance, in TCS/FDV/Pt-Cat with 1.5 wt.% Fe2O3, the heat release rate exceeded 624 K · min?1 and the pressure rose above 25 MPa during the exothermic reaction. 相似文献
143.
Yatsukawa Y Ito H Matsuda T Nakamura M Watai M Fujita K 《Journal of AOAC International》2011,94(4):1319-1327
A new analytical method for the simultaneous determination of seven fluoroquinolones, namely, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, orbifloxacin, sarafloxacin, and difloxacin, especially in dark-colored honey, has been developed. Fluoroquinolone antibiotics were extracted from samples with MacIlvaine buffer solution (pH 4.0) containing EDTA disodium salt dihydrate. The extracts were treated with both a polymeric cartridge and a metal chelate affinity column preloaded with ferric ion (Fe3+). LC separation with fluorescence detection was performed at 40 degrees C using an Inertsil ODS-4 analytical column (150 x 4.6 mm, 3 microm). The mobile phase was composed of 20 mM/L citrate buffer solution (pH 3.1)-acetonitrile mixture (70 + 30, v/v) containing 1 mM/L sodium dodecyl sulfate. Lomefloxacin was used as an internal standard. The developed method was validated according to the criteria of European Commission Decision 2002/657/EC. Decision limits and detection capabilities were below 2.9 and 4.4 microg/kg, respectively. 相似文献
144.
Yabuuchi N Yamakawa Y Yoshii K Komaba S 《Dalton transactions (Cambridge, England : 2003)》2011,40(9):1846-1848
A nearly single-phase of a low-temperature (LT) phase of Li(2)FeSiO(4) is prepared by a hydrothermal method at 150 °C. We report the detailed crystal structure of LT-Li(2)FeSiO(4) (S.G. Pmn2(1)) by applying Rietveld/MEM analysis to the synchrotron XRD pattern. LT-Li(2)FeSiO(4) shows 150 mA h g(-1) as the positive electrode materials of rechargeable batteries. 相似文献
145.
Construction of carbocyclic ring of indoles using ruthenium-catalyzed ring-closing olefin metathesis
The selective synthesis of substituted indoles was achieved by the ring-closing olefin metathesis (RCM)/elimination sequence or the RCM/tautomerization sequence of functionalized pyrrole precursors. The RCM/elimination sequence was also applied to double ring closure to yield a substituted carbazole. 相似文献
146.
Zeng J Wang W Deng P Feng W Zhou J Yang Y Yuan L Yamato K Gong B 《Organic letters》2011,13(15):3798-3801
Hydrogen-bonded zippers bearing terminal alkene groups were treated with Grubbs' catalyst, leading to covalently cross-linked zippers without violating H-bonding sequence specificity. The yield of a cross-linked zipper depended on the stability of its H-bonded precursor, with a weakly associating pair giving reasonable yields only at high concentrations while strongly associating pairs showed nearly quantitative yields. The integration of thermodynamic (H-bonding) and kinetic (irreversible C═C bond formation) processes suggests the possibility of developing many different covalent association units for constructing molecular structures based on a self-assembling way. 相似文献
147.
Takashima-Hirano M Tazawa S Takahashi K Doi H Suzuki M 《Chemical & pharmaceutical bulletin》2011,59(8):1062-1064
Ramelteon (TAK-375) is a novel melatonin receptor agonist that is used for clinical treatment of insomnia. The present report describes radiolabeling of ramelteon with the short-lived positron-emitter 11C (T(1/2)=20.4 min) by 2 methods. One method was [11C]methylation of an acetoamide precursor and the other was [11C]acylation of the corresponding amine precursor. First, [11C]methylation method showed the low reproducibility together with the production of many kinds of side products from which the [11C-methyl]Ramelteon was separated with chemical purity of <28% and radiochemical purity of >98%. Whereas, the [11C]acylation method showed high efficiency and reproducibility with a good radiochemical yield (22-43%, decay corrected), high chemical and radiochemical purities (>99% each), and high specific activity (43-162 GBq/μmol) (n=5) after HPLC purification. [11C]Ramelteon is a potential positron emission tomography (PET) probe for imaging the melatonin receptor. 相似文献
148.
Akiko Watanabe Naotoshi Kiyota Tetsuo Yamasaki Kazuhiro Tanda Tatsunori Miyagoe Masanori Sakamoto Masami Otsuka 《Journal of heterocyclic chemistry》2011,48(5):1132-1139
Four isomers of the monomer of peptide nucleic acid (PNA) were derived from (2S,4R)‐4‐hydroxyproline; they had different stereochemistries at the C2 and C4 positions in the pyrrolidine ring. These different backbone conformations corresponding to four different stereochemistries were realized through a combination of inversions at the C2 and the C4 positions in pyrrolidine ring. The obtained backbone frameworks were reacted with N‐benzoyl thymine to give the corresponding PNA monomers. Spectroscopic comparison of the resultant monomers confirmed their stereochemistries. J. Heterocyclic Chem., (2011). 相似文献
149.
We have shown from in situ synchrotron x-ray diffraction measurements that there are two thermodynamically stable liquid forms of SnI(4), depending on the pressure. Based on the liquid-liquid critical point scenario, our recent measurements suggest that the second critical point, if it exists, may be located in a region close to the point at which the melting curve of the crystalline phase abruptly breaks. This region is, unlike that of water, experimentally accessible with relative ease. 相似文献
150.
The new carboxamide protecting group, 4-(tert-butyldimethylsiloxy)-2-methoxybenzyl (SiMB), has been developed. While this SiMB group can be removed using mild basic desilylation methods, it can also be deprotected under strongly acidic or oxidative conditions. An application of this group to simple carboxamide groups, as well as to more complex and acid-sensitive adenosine derivatives containing a cyclophane scaffold, was also demonstrated. 相似文献