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141.
Takahiro Noda Shogo Tsuda Motoyuki Mori Tatsuro Suzuki Shigenobu Takigawa Chie Matsuura‐Endo Hiroaki Yamauchi Mahammed Zaidul Islam Sarker 《Starch - St?rke》2012,64(3):229-236
To test the effects of the annual fluctuation of the environmental factors on the starch properties in potato tuber development, starches were isolated from potato cultivars grown for ten consecutive years (2001–2010) on the experimental farm in Memuro, Hokkaido, the northernmost island of Japan. The median granule size, phosphorus content, and rapid visco‐analyzer pasting properties, peak viscosity, breakdown, and pasting temperature of these starches were analyzed. Daily temperature and precipitation records in Memuro were obtained from the Japan Meteorological Agency. Moreover, the correlation coefficients of yearly accumulated temperature and precipitation from flowering to harvesting with all the starch quality parameters were calculated. No relationships of accumulated temperature with median granule size, peak viscosity, and breakdown were found. The low phosphorus content was slightly associated with the high accumulated temperature. The pasting temperature was significantly and positively correlated with the accumulated temperature, suggesting that the pasting temperature strongly responds to the environmental temperature during potato tuber development. In contrast, all the starch quality parameters were almost irrespective of the precipitation during potato tuber development. 相似文献
142.
To investigate unusual odd-chain fatty acids (FA) from gonads of archaeogastropods, limpets Cellana grata and Cellana toreuma, a subfraction enriched in FA with two double bonds extracted from the gonads was obtained by using argentation thin-layer chromatography. The resulting fraction was analyzed by using capillary gas chromatography-mass spectrometry of its methyl esters, 3-pyridylcarbinol esters and pyrrolidide derivatives. Six novel all-cis diene isomers were identified as 7,18-heneicosadienoic (21:2Δ7,18), 8,14-tricosadienoic (23:2Δ8,14), 9,15-tricosadienoic (23:2Δ9,15), 7,18-tricosadienoic (23:2Δ7,18), 9,18-tricosadienoic (23:2Δ9,18), and 9,20-tricosadienoic (23:2Δ9,20) acids. In the present study, the differences in the proportion of tricosadienoic acid isomers between the ovary lipids of C. grata and C. toreuma were recognized. 相似文献
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146.
Sn-Zn alloy thin films were deposited on a polyester (PET) film substrate by co-evaporation and evaluated their surface, tensile and adhesion properties with a vacuum forming test and pull test.Relationship between the surface roughness and elemental composition of these thin films was evaluated. The surface roughness decreased with increase of the Sn content.The tensile property was estimated by observations of micro-cracks of the thin films due to a vacuum forming test. Sn-Zn alloy thin film, whose elemental composition is 85:15 (wt%), had high vacuum forming durability.The adhesion strength between the Sn-Zn alloy thin films and PET substrate was measured with a pull test apparatus. The pull strength decreased with increase of the Sn content. 相似文献
147.
Feng Wang Jie Xu Xiaoqiang Li Jin Gao Lipeng Zhou Ryuichiro Ohnishi 《Advanced Synthesis \u0026amp; Catalysis》2005,347(15):1987-1992
We conducted the liquid phase oxidation of toluene with molecular oxygen over heterogeneous catalysts of copper‐based binary metal oxides. Among the copper‐based binary metal oxides, iron‐copper binary oxide (Fe/Cu=0.3 atomic ratio) was found to be the best catalyst. In the presence of pyridine, overoxidation of benzaldehyde to benzoic acid was partially prevented. As a result, highly selective formation of benzaldehyde (86% selectivity) was observed after 2 h of reaction (7% conversion of toluene) at 463 K and 1.0 MPa of oxygen atmosphere in the presence of pyridine. These catalytic performances were similar or better than those in the gas phase oxidation of toluene at reaction temperatures higher than 473 K and under 0.5–2.5 MPa. It was suggested from competitive adsorption measurements that pyridine could reduce the adsorption of benzaldehyde. At a long reaction time of 4 h, the conversion increased to 25% and benzoic acid became the predominant reaction product (72% selectivity) in the absence of pyridine. The yield of benzoic acid was higher than that in the Snia‐Viscosa process, which requires corrosive halogen ions and acidic solvents in the homogeneous reaction media. The catalyst was easily recycled by simple filtration and reusable after washing and drying. 相似文献
148.
This paper proposes some basic methods of content search yielding high user utility or user's satisfaction from numerous information sources scattered over large‐scale networks. In these methods, the search policy is decided by the estimated user utility gain and/or current user utility for each search action, and the most favorable combination of information sources and search content items is selected so as to enlarge the total user utility of the entire search activity. In addition, we evaluate the efficiency of the methods by computer simulations, in which we specify the network topology, user utility functions, probabilities of existence of the search content items in each information source, and so on, apply the proposed methods and other methods for comparison, and compare their aggregate utility gains as an estimation index. The proposed methods are found to achieve good performance in general and an index value about 2.45 times that of ordinary search is observed in an extreme simulation scenario. We discuss the pros and cons of the proposed methods for all the simulation scenarios. 相似文献
149.
In practice, water pricing is the main economic instrument used to discourage the wasteful use of residential water. Owing to considerations of affordability, residential water is systematically underpriced because water is essential for life. Such a low price results in water being used inefficiently. This paper proposes a system that supplements the existing price system with a cap-and-trade measure to reconcile conflicts among the goals of residential water use. It forces all people (independent of income) to be faced with reasonable price signals and to use water efficiently. The poor could, however, gain from trade and afford water. By taking advantage of the agent-based model, a simulation of this system applied to Taipei, Taiwan shows that those with lower income per capita are better off under this system even though the equilibrium price of residential water is higher. The simulated average price elasticity of market demand is ?0.449. 相似文献
150.
SM Ekramullah Y Saitoh N Arita T Ohnishi T Hayakawa 《Canadian Metallurgical Quarterly》1996,138(12):1449-1455
In order to improve our ability to predict the regrowth of nonfunctioning pituitary adenomas, we tried to assess the correlation between growth fractions with Ki-67 and PCNA (proliferating cell nuclear antigen) and tumour doubling times in regrowing tumours, and also to find out any difference of growth fractions between the regrowing and the cured cases. In 33 patients with non-functioning pituitary adenomas, 14 cases including 11 with cavernous sinus invasion showed residual tumour on MRI after the operation (regrowing group) and 19 cases had no tumour regrowth on MRI within 5 years after the operation (cured group). Immunocytochemical studies were done with monoclonal antibodies (anti-PCNA, anti-Ki-67: MIB-1). The growth fraction of each tumour was estimated by calculating the ratio of the positive nuclei to the total number of tumour cells with the aid of an image analyser (Mac SCOPE). The tumour doubling times were estimated from serial CT or MRI with the aid of the image analyser (NIH image). Ki-67 staining indices ranged from 0.2% to 1.5% (n = 14, 0.86 +/- 0.10%; mean +/- SEM) in the regrowing group, and from 0.1% to 0.5% (n = 19, 0.23 +/- 0.03%) in the cured group. PCNA staining indices of the regrowing group ranged from 0.6% to 24% (n = 14, 3.7 +/- 1.6%). In the regrowing group, the tumour doubling times ranged from 200 to 2550 days (930 +/- 180 days), and showed a significant inverse correlation with Ki-67 staining indices, but no correlation with PCNA staining indices. The regrowing group showed a significantly higher Ki-67 staining index (n = 14, 0.86 +/- 0.10%) than the cured group (n = 19, 0.23 +/- 0.03%) (p < 0.01). These results indicate that immunocytochemical studies using MIB-1 may be better than those with PCNA for the prediction of regrowth in non-functioning pituitary adenomas. Immunocytochemical study with MIB-1 could lead to the accurate prediction of the rapid regrowing lesions in non-functioning adenomas. 相似文献