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在实验基础上确立了含钛高炉渣水解制取钛白过程中钛液TiOSO4浓度随时间的变化关系,经数学分析建立了动力学方程并讨论了方程的适应性。为信水解过程听进一步研究和生产实践提供了数据。 相似文献
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136.
为优化恩拉霉素提取工艺,以70%甲醇溶液为提取剂,提取恩拉霉素,经过浓缩、脱色、结晶、重结晶,制备高含量恩拉霉素产品。得到最佳提取工艺条件是:浸提pH3.5~4.0,浸提温度30 ℃,三次浸提时间1 h,一次浸提料液比1∶7,二次浸提料液比1∶3,三次浸提料液比1∶3,活性炭用量是浓缩液体积的1.0%~1.5%,粗精粉重结晶得到纯品,含量97%。 相似文献
137.
NaOH溶液脱绒对白羊草种子活力的影响 《畜牧与饲料科学》2022,43(5):87-92
[目的] 探究NaOH溶液脱绒处理对白羊草(Bothriochloa ischaemum)种子活力的影响,为机械化播种提供便利条件。[方法] 分别利用浓度为10%、20%、30%、40%、50%(W/V)的NaOH溶液对白羊草种子进行脱绒处理0(CK)、1、5、10、15 min,分析其对发芽率(Gp)、发芽指数(Gi)、平均发芽时间(MGT)、幼苗活力指数(SVI)的影响,筛选白羊草种子NaOH溶液脱绒的最佳条件。[结果] NaOH溶液浓度及处理时间均对白羊草种子活力具有极显著(P<0.01)影响。相同处理时间下,白羊草种子脱绒1~10 min后Gp、Gi随NaOH溶液浓度的增加而增加,脱绒1 min和10 min后SVI随着NaOH溶液浓度的增加而增加,脱绒5 min后SVI随NaOH溶液浓度的增加呈先降低后升高的趋势,脱绒15 min时Gp、Gi和SVI随NaOH溶液浓度的增加呈先升后降的趋势;在20%~50%的NaOH溶液浓度下,脱绒后白羊草种子Gp、Gi和SVI随处理时间的增加呈先升后降的趋势。经NaOH溶液脱绒处理后白羊草种子的MGT均高于CK。[结论] 适宜浓度的NaOH溶液浸种能有效脱去白羊草种子表面的绒毛,提高白羊草种子的活力。浓度为50%的NaOH溶液浸种5 min对白羊草种子活力的促进效果最好。 相似文献
138.
Effects of NaCl on seed germination, leaf gas exchange and seedling growth were investigated. The germination of P. tatarinowii seeds was delayed in the presence of NaCl, and was significantly inhibited when NaCl concentration exceeded 17 mM (1.0 g·L−1). NaCl treatments induced reductions of transpiration rate, stomatal conductance and net photosynthetic rate and their reductions
were significant with the increasing of NaCl concentration. However, intercellular CO2 concentration in seedling leaves under salt stress was significantly higher than that of controls. There was a significant
reduction in survival, basal diameter increment and height increment with increasing NaCl concentration 50 days after NaCl
treatment, and a significant reduction in the dry weight increment of roots, stems, and leaves was also observed in the NaCl
treatments. The deleterious effect on the biomass increment was more evident in the case of stems and leaves. Results from
this study suggest that P. tatarinowii is sensitive to salinity stress and the salinity threshold for seedling growth might be less 34 mM (2.0 g·L−1).
Biography: FANG Sheng-zuo (1963–), male, Professor, College of Forest Resources and Environment, Nanjing Forestry University, Nanjing
210037, P. R. China. 相似文献
139.
The resin content in larch wood is usually determined by the traditionalBenzene-Alcohol Extract Method(BAEM).In order to meet the requirement of production prac-tice,the authors present two simple quick determination methods,IR lamp method and hydrogenperoxide solution method.Compared with the results of traditional method,the results of newmethods are nearly the same as former,therefore,both two methods can reflect the change condi-tion of resin content in wood. 相似文献
140.
For the fundamental study of oxygen delignification of kraft pulp, structural changes of kraft lignin during alkaline oxygen treatment were investigated with the use of infrared measurement with attenuated total reflectance (ATR) technique. In the neutralized reaction mixture of alkaline oxygen-treated kraft lignin, there is a significant amount of NaCl, so that the spectral changes of water due to the coexistence of NaCl was investigated, and how to remove the huge absorption of NaCl solution is discussed. Sodium vanillate–NaCl solutions were employed as model solutions for the reaction mixture. Partial least square (PLS) regression was applied for the prediction of NaCl concentration, and the spectrum of NaCl solution was subtracted from the spectrum of sodium vanillate–NaCl solution as background measurement. This allowed us to obtain the vanillate spectra free from the absorption of NaCl solution. In addition, the mathematical method for reconstructing the spectrum of NaCl solution is discussed. The spectrum of NaCl solution is reconstructed as the linear combination of basic spectra calculated by singular value decomposition (SVD), and it was subtracted from that of the sodium vanillate–NaCl solution. By this procedure, the vanillate spectra were also obtained quantitatively, as has been demonstrated in PLS regression study. It was also confirmed that the quantitative spectra of high molecular weight fraction of alkaline oxygen-treated kraft lignin were obtained by the use of this reconstruction technique.Parts of this report were presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, Japan, April 2002 and the 12th International Symposium on Wood and Pulping Chemistry, Madison, USA, June 2003 相似文献