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61.
Christine Kenter Christa M Hoffmann 《Journal of the science of food and agriculture》2006,86(1):62-70
The chemical composition of sugar beet is the most important parameter affecting its processing. Sugar factories require beet with high concentrations of sucrose and low concentrations of melassigenic substances to maximise the amount of extractable sugar. In order to plan the processing campaign, forecasts of root and sugar yield by prediction models are possible but there are no means to predict the technical quality of the beet. In the present study, the seasonal development and physiological relationships of different parameters of sugar beet quality were analysed. In order to estimate possibilities for quality forecasts, the concentrations of beet quality variables in October were correlated with corresponding quality measurements in late summer and to weather variables during the growing season by linear regressions. In 2000 and 2001, 27 field trials were conducted on commercial farm fields in all sugar beet growing areas in Germany. From June to October, sequential samples were taken every 4 weeks and the concentrations of sucrose, potassium, sodium, total soluble nitrogen, α‐amino nitrogen, nitrate, betaine, reducing sugars and marc in the beet were determined. The sucrose concentration increased progressively until the final harvest date in autumn, whereas the concentrations of the melassigenic substances decreased markedly until late summer and remained fairly constant as the season progressed. Marc concentration was the most stable of the parameters analysed. The sucrose concentration was positively correlated with the concentrations of dry matter, betaine and marc, but negatively with nitrate concentration and leaf yield throughout the season. The correlation between the concentrations of sucrose and nitrogenous compounds measured in summer and their final concentrations in autumn was rather weak. However, it was close for potassium, sodium and marc and a satisfactory prediction of their final concentrations was possible by the end of August. Based on weather data, beet quality was not predictable. Therefore, it seems to be difficult to integrate beet quality parameters into prediction models. Copyright © 2005 Society of Chemical Industry 相似文献
62.
The results of ultrasonic velocity and attenuation measurements in deuterated betaine phosphite (DBPI) and its compounds near the antiferrodistortive phase transition (PT) are presented for X, Y and Z crystallographic directions. For longitudinal ultrasonic modes propagating along X and Z axes in DBPI the critical slowing down in ultrasonic velocity and attenuation maxima have been observed at PT. Instead, we have not found the critical elastic anomalies for longitudinal Y mode. In DBP crystals the elastic anomalies appeared at PT for all X, Y and Z modes. In solid solution DBP/DBPI the orientation dependencies of elastic anomalies varied from those of DBPI to those of DBP. The phase diagram has been obtained from ultrasonic data. The experimental data in the antiferrodistortive phase have been interpreted in terms of the mean field Landau theory. It is shown that the phase transitions are very close to the tricritical ones. 相似文献
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以芥酸、N,N-二甲基-1,3-丙二胺与氯乙酸钠为原料,经过酰胺化、季铵化两步反应,合成了芥酸酰胺丙基羧基甜菜碱EBC。使用FTIR、MS对酰胺中间体EA和甜菜碱产物EBC的结构进行了表征。评价了甜菜碱EBC的表界面性能、吸附特性和增黏性。结果表明,该表面活性剂的临界胶束浓度(CMC)为1.02×10-5mol/L,对应的表面张力γCMC为29.60 mN/m;最小烷烃碳数(nmin)为16;无碱条件下,EBC与大庆和苏丹油田原油达到10-4~10-3mN/m数量级的超低界面张力,m(EBC)∶m(DABS)=8∶2,复配体系质量分数0.001%~0.20%与长庆马岭油田原油达到超低界面张力,界面性能优异,且抗稀释能力强;该表面活性剂在天然油砂上的吸附量为0.07~0.51 mg/g砂,小于1.0 mg/g砂的指标要求;而且具有明显的增黏性能。甜菜碱EBC可作为较理想的驱油用表面活性剂应用于化学复合驱。 相似文献
66.
Jayaranjan R. Kar John E. Hallsworth 《International Journal of Food Properties》2016,19(11):2510-2521
We used glycine betaine (5–20% w/v) for blanching green peas (100°C, 60 s), and their subsequent freezing and storage (–20°C, 90 days). Blanching after the addition of glycine betaine at ≥10% (w/v) followed by a 90 day storage period which resulted in the most desirable outcome: higher vitamin C levels, a superior green color, enhanced organoleptic quality and texture, and improved retention of peroxidase and lipoxygenase activity relative to control peas (no glycine betaine added). Microscopic characterizations of control and treated peas revealed that glycine betaine acts as a cryoprotectant which maintains cellular integrity. Glycine betaine (10% w/v) could be used commercially for production of frozen peas with better quality attributes. 相似文献
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将脂肪醇聚氧乙烯醚硫酸酯盐(AES)烷基醇酰胺(6501)甜菜碱溶于水中,再加入其它助剂,制得羊绒洗涤剂,实验确定了最佳组分配比。 相似文献
69.
月桂酸乙酯基甜菜碱表面活性剂的合成研究 总被引:1,自引:0,他引:1
以N,N-二甲基乙醇胺与月桂酸为原料,对甲苯磺酸作催化剂,合成了月桂酸乙酯基二甲基叔胺中间体,继而与氯乙酸钠反应制得标题化合物.中间体合成的正交实验优化条件为:n(N,N二甲基乙醇胺):n(月桂酸)=1.6:1;催化剂用量为反应物总质量的1.5% ;170℃反应12 h,最高产率> 85%.最终产品合成的均匀实验优化结果:异丙醇为溶剂,n(中间体):n(氯乙酸钠)=1:2.2,90℃反应21 h,中间体转化率>8%.得到的标题化合物经丙酮重结晶提纯,HPLC法分析其质量分数>99%,使用FT-IR、ESI-MS 、1 HN M R进行了结构表征. 相似文献
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