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111.
采用静态消化模型和半动态消化模型,评价经透析处理和未经透析处理的大豆蛋白的胃消化特性。结果表明:在静态消化模型中,透析对大豆蛋白的胃消化过程没有影响;但在半动态消化模型中,未经透析的大豆蛋白pH值、排空内容物的干物质质量和游离氨基的含量与经透析处理的大豆蛋白存在一定差异,表明未经透析处理的大豆蛋白保留较多大豆中的成分,使其缓冲能力更强,胃排空滞后,蛋白质消化速率减慢。此外,静态消化模型和半动态消化模型有不同的优势,所以可以根据不同的研究目的采用不同的消化模型。这项工作将为大豆蛋白产品的开发和健康效应提供新的见解。 相似文献
112.
113.
渗析法确定土水特征曲线的试验研究 总被引:1,自引:0,他引:1
土水特征曲线(SWCC)描述的是土体基质吸力与含水率之间的关系,它对于非饱和土的研究具有重要意义。在测定SWCC的各种方法中,渗析法的试验过程较简单、安全且可靠。本文以合肥地区非饱和膨胀土为研究对象,详细介绍了渗析法获得SWCC的试验过程和技术要领,并采用水浴恒温振荡器代替磁力搅拌器改进了渗析试验。结果表明:采用水浴恒温振荡器进行渗析试验是合理可行的,其优点是一次可以进行相同环境条件下多个浓度的渗析试验;使用水浴恒温振荡器对合肥地区膨胀土进行渗析试验时,其渗析平衡时间约为8天。在此基础上,采用Fredlund-Xing模型的3种型式对渗析试验结果进行了曲线拟合,得到了试验土体的SWCC及其拟合参数,可知模型3种型式的区别主要在高吸力部分。 相似文献
114.
信息网络数据立方(InfoNetCube)的计算是进行信息网络在线分析处理的基础.然而,不同于传统的数据立方,信息网络数据立方由多个子方体格组成,每个方体格中的任意方体(cuboid)的任意单元格都包含一个主题图(或称图度量),因而空间开销较传统数据立方大2个数量级以上.如何快速、高效进行信息网络数据立方的部分物化是极具挑战的研究课题.本文提出基于“透析计算”思想的信息网络立方物化策略,通过主题图度量在信息维和拓扑维上反单调性运用,提出基于“透析计算”的空间剪枝算法,快速透析掉不可能命中的子图度量、方体单元、方体乃至方体格.实验结果表明,本文提出的基于“透析计算”的部分物化策略,可以对信息网络方体进行有效剪枝,算法较基于基本方体的部分物化策略运行时间平均降低75%. 相似文献
115.
Remi O. Hombrouckx Dirk S. De Wachter Pascal R. Verdonck 《Hemodialysis international. International Symposium on Home Hemodialysis》1998,2(1):26-29
Go slow” dialysis is a gentle, intermittent hemodialysis therapy for acute renal failure patients, with advantages compared to slow, continuous therapies. It employs a recirculating closed dialysate circuit. A two-pool urea kinetic model is elaborated to determine kinetic parameters from blood and dialysate concentrations. This will allow quantification of the therapy. Variable clearance is included to accurately describe the kinetic process. The model is tested in an acute renal failure patient. Solute removals, as determined from direct dialysis quantification and by the model, are comparable. Variable clearance is not required to determine the kinetic parameters, because the constant mean clearance delivers equal results. The dialysis dose, as defined, allows comparison with chronic renal therapies. It requires solute removal determined from dialysate sampling and time-averaged concentration (TAC) from the urea kinetic modeling. In the test patient, dialysis dose is lower compared to standard thrice-weekly therapies because of its lower efficiency and higher TAC, a result of his highly catabolic state. 相似文献
116.
Chen-Li Chiang Shau-Wei Tsai 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,54(1):27-32
A recycle dialysis stirred cell has been successfully used for integrating the reaction and product recovery of the lipase-catalyzed hydrolysis of olive oil in bis (2-ethylhexyl) sodium sulfosuccinate (AOT)-iso-octane reversed micelles. The resistance of membrane to reversed micelles was monitored by the water content and found to be 95.9% rejection after 24 h and 93.4% rejection after 48 h. The resistance of the membrane to free surfactants, by monitoring the UV absorption, was found to be 98.5% rejection after 10 h and 97.3% rejection after 24 h. Mathematical formulations involving the enzymatic reaction coupled with mass transfer were developed for predicting the performance of a membrane reactor. Theoretical predictions in terms of time course of oleic acid concentrations were found to be in agreement with the experimental results. 相似文献
117.
Noor Ul Afsar Dongbo Yu Congliang Cheng Kamana Emmanuel Liang Ge Bin Wu 《分离科学与技术》2017,52(6):1106-1113
We report polyvinyl alcohol (PVA)-based hybrid membranes composed of salt of lignin sulfonic acid (LSA) and tetraethyl orthosilicate. The concentration of LSA with respect to PVA varied from 10% to 40%. The hybrid membranes showed water uptake (WU) in the range of 122–210%, ion exchange capacities in the range of 0.32–0.75 mmol g?1, dialysis coefficient (UOH) from 0.0068 to 0.0119 m h?1, and selectivity (S) from 15 to 26. The hybrid membranes also showed thermal and mechanical stability. 相似文献
118.
Małgorzata Janiszewska Andrea Arguillarena Magdalena Wajs Katarzyna Staszak 《分离科学与技术》2020,55(12):2227-2237
ABSTRACT Diffusion dialysis (DD) was proposed as a pretreatment step to reduce the acidity of real sulfate/chloride pregnant leach solutions containing cobalt(II) and nickel(II). Optimum DD conditions that enable reduction of acidity in the feed while maintaining a high rejection level of metal ions present in PLS were proposed, e.g. for 0.06 dm3/min flow of both aqueous phases H+ concentration in the dialysate reached 3.8 and 2.99 M for PLS1 and PLS2, respectively. Acid diffusion coefficients varied from 0.32 ?10 ?6 to 3.15?10?6 m/s and decreased with increasing phase flow rates. Moreover, dialysate neutralization was beneficial for the H+ reduction in the feed. 相似文献
119.
Boron removal from aqueous solution by using plasma-modified and unmodified anion-exchange membranes
The removal of boron from aqueous solution through plasma-modified and unmodified AFX anion-exchange membrane was investigated by the Donnan dialysis (DD) method. The surface of anion-exchange membrane was treated by electron cyclotron resonance plasma (ECR) to enhance the performance. The effects of plasma-modified anion-exchange membrane and initial boron concentration on the boron removal were investigated at 25 °C. The optimum pH was chosen as 9.5 from the literature data. The flux values (J) and recovery factor (RF) of boron were obtained before and after the plasma modification. Under Donnan dialysis conditions, flux values and recovery factors of boron were calculated and the highest values were obtained for plasma-modified AFX membrane as compared with the unmodified one. This situation can be explained by change of morphology of pores in the plasma-modified membrane. In addition, the different valence anions also influence the flux of boron and the order of flux was found as Cl− > SO42−. 相似文献
120.
The removal of phosphate from aqueous solution by Donnan dialysis with anion-exchange membrane was investigated.The results show that phosphate could be removed from aqueous solution without supplying external high pressure or electrical potential.Under the conditions of influent phosphate of 2.0 mg/L,counterion(Cl-) concentration of 0.1 mol/L,stirring speed of 500 r/min and phase temperature of 298 K,the removal of phosphate achieves 70.0%.Decreasing counterion concentration has little influence on the removal of phosphate,but phosphate amount in anion-exchange membrane increases significantly.With the increase of stirring speed and phase temperature,the removal efficiency of phosphate greatly is improved.Existing forms of phosphate in aqueous solution affected transport of phosphate and only strong acidic pH of feed solution (pH=3.0) decreases the removal of phosphate.Transport of phosphate is also accompanied by change of pH value of feed solution.In consequence,it might be a promise potential process for phosphate advanced wastewater treatment,especially in the area where high salted nature water can be utilized. 相似文献