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81.
Toshimitsu Ichimori Shinichi Yamazaki Kunio Kimura 《Journal of polymer science. Part A, Polymer chemistry》2013,51(20):4301-4308
Composition control of aromatic poly(thioester‐amide) was examined by the reaction‐induced phase separation during polymerization of S‐acetyl‐4‐mercaptobenzoic acid (AMBA) and p‐acetylaminobenzoic acid (AABA) in aromatic solvent. The poly(thioester‐amide)s were obtained as precipitates and their yields became lower at the middle range of the content of AMBA in feed (χf). The contents of p‐mercaptobenzoyl (MB) moiety (χp) in the precipitates prepared without shearing were in good agreement with the χf values. In contrast to this, the χp values of the precipitates prepared at χf of 50–70 mol % under shearing were much lower than the χf values. The reaction rate of AMBA increased with shearing, whereas that of AABA was unchanged by shearing. This shearing effect on the reaction rates accelerated to form the homo‐oligomers. The solubility of MB oligomers enhanced by shearing, whereas that of p‐benzamide oligomers did not enhance owing to the strong interaction through hydrogen bonding. The MB oligomers were inhibited to be precipitated, resulting in the lower χp values than the χf values. The composition could be controlled by the application of the shearing to the heterogeneous polymerization. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4301–4308 相似文献
82.
T Adzuhata J Inotsume T Okamura R Kikuchi T Ozeki M Kajikawa N Ogawa 《Analytical sciences》2001,17(1):71-76
Fog and rain water samples were collected at the same time in the Akita Hachimantai mountain range in northern Japan from June to September in 1998 and 1999. The various ion concentrations in these samples were analyzed, and the fog droplet sizes were measured for each fog event. As the fog droplet size increased, the ion concentration decreased. The slope of log-log plots of the concentration versus the droplet size differed with the kind of ion. In order to characterize the air pollutant, moreover, these data were quantitatively analyzed by an oblique rotational factor analysis. We found that three factors were extracted as the air pollutant source: (NH4)2SO4, acids (HNO3 + H2SO4) and sea-salt. Combining the factor analysis with the 72 h back-trajectory at 850 hPa level, we found that the contribution of each factor varied with the transport pattern of air masses. 相似文献
83.
Haruko Okamura 《Graphs and Combinatorics》1995,11(2):141-170
LetG be ak-edge-connected graph and letf
1,f
0,f
2 be consecutive edges. We call a cycleC (not necessarily simple) 2-reducible ifG – E(C) is (k – 2)-edge-connected. We here characterize the graphsG having no 2-reducible cycle containingf
1,f
0 andf
2. 相似文献
84.
Chen MS Chen M Takamizawa S Okamura TA Fan J Sun WY 《Chemical communications (Cambridge, England)》2011,47(13):3787-3789
A unique 4-fold interpenetrated (10,3)-b copper(II) framework exhibits reversible dehydration and rehydration in a single-crystal-to-single-crystal (SC-SC) process, and the dehydrated material can encapsulate CH(3)OH molecules, again in a SC-SC fashion, and shows selective adsorption of H(2) and CO(2) over N(2). 相似文献
85.
Takagi T Shum D Parisi M Santos RE Radu C Calder P Rizvi Z Frattini MG Djaballah H 《Combinatorial chemistry & high throughput screening》2011,14(8):669-687
Several assay technologies have been successfully adapted and used in HTS to screen for protein kinase inhibitors; however, emerging comparative analysis studies report very low hit overlap between the different technologies, which challenges the working assumption that hit identification is not dependent on the assay method of choice. To help address this issue, we performed two screens on the cancer target, Cdc7-Dbf4 heterodimeric protein kinase, using a direct assay detection method measuring [(33)P]-phosphate incorporation into the substrate and an indirect method measuring residual ADP production using luminescence. We conducted the two screens under similar conditions, where in one, we measured [(33)P]-phosphate incorporation using scintillation proximity assay (SPA), and in the other, we detected luminescence signal of the ATP-dependent luciferase after regenerating ATP from residual ADP (LUM). Surprisingly, little or no correlation were observed between the positives identified by the two methods; at a threshold of 30% inhibition, 25 positives were identified in the LUM screen whereas the SPA screen only identified two positives, Tannic acid and Gentian violet, with Tannic acid being common to both. We tested 20 out of the 25 positive compounds in secondary confirmatory study and confirmed 12 compounds including Tannic acid as Cdc7-Dbf4 kinase inhibitors. Gentian violet, which was only positive in the SPA screen, inhibited luminescence detection and categorized as a false positive. This report demonstrates the strong impact in detection format on the success of a screening campaign and the importance of carefully designed confirmatory assays to eliminate those compounds that target the detection part of the assay. 相似文献
86.
87.
Journal of Theoretical Probability - We consider symmetric stable-type processes with degenerate/singular Lévy densities via Dirichlet form theory. We give conditions of some global path... 相似文献
88.
The possible formation of antihydrogen atoms via the collision of metastable antiprotonic helium atoms with positrons and
positroniums is discussed based on the known behavior of positrons in helium media. 相似文献
89.
A novel synergistic extraction system was investigated for the possible selective separation of light lanthanoids using an ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, as an extraction solvent and 2-thenoyltrifluoroacetone and 18-crown-6 as extractants. Trivalent lanthanum was efficiently extracted as a cationic ternary complex by the cation-exchange process, whereas europium and lutetium showed relatively low extractability without forming respective ternary complexes. This result is thought to originate in a size-fitting effect of 18-crown-6 to lanthanum and the unique nature of the ionic liquid as a chelate extraction solvent. 相似文献
90.