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1.
N503萃取Fe3+工艺研究   总被引:2,自引:0,他引:2  
用N503对Fe3 溶液进行萃取实验研究.结合试验详细阐述了萃取相Fe质量分数与水相中Fe3 质量浓度变化的曲线关系,并分析了主要因素对萃取的影响.通过再生萃取剂的循环萃取试验研究了其萃取效果,结果表明再生萃取剂可循环使用.  相似文献   

2.
用恒界面搅拌池研究了伯胺N_(1923)萃取盐酸、硝酸和高氯酸的动力学。从实验结果推断出萃取反应速率控制步骤是下述两步界面化学反应: RNH_(2(i)) HA(?)RNH_3A_((i)) RNH_3A_((i)) RNH_(2(o))(?)RNH_3A_((o)) RNH_(2(i)) 文中就不同酸根离子对萃取选率的影响作了讨论。  相似文献   

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叔胺—盐权体系萃取分离铝中的铁和铅   总被引:1,自引:0,他引:1  
《吉林工学院学报》1999,20(4):16-18
  相似文献   

5.
萃取新技术在食品工业中的应用   总被引:3,自引:0,他引:3  
作为新的萃取技术,超临界流体萃取、微波萃取、双水相萃取具有许多优点.介绍了这几种萃取技术的机理,综述了其在食品工业中的应用,讨论了它们的工业化应用前景及存在的问题,以期加速其在食品工业中的应用.  相似文献   

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研究了不同稀释剂中,2-乙基己基膦酸单(2-乙基己基)酯从硝酸介质中对Zn(Ⅱ)的萃取,其萃取能力在不同稀释剂中按正己烷〉四氢化碳〉苯〉氯仿的顺序变化。萃取平衡常数与稀释剂的极性参数DP、S间呈线性关系。  相似文献   

8.
超临界萃取法提取海带多不饱和脂肪酸的研究   总被引:2,自引:0,他引:2  
对以海带(Laminaria japonica)为原料,采用超临界CO2萃取技术提取海藻多不饱和脂肪酸的可行性进行了研究,结果表明,当CO2流量2.5-3.5L/h,萃取压力25MPa,萃取温度30℃,萃取时间3h,原料粒度40-60目,分离压力5MPa和分离温度35℃时最利于海带脂质的提取,此萃取条件可使海带总脂肪酸中多不饱和脂肪酸含量达到67.2%。  相似文献   

9.
P5709萃取镉的机理研究   总被引:1,自引:0,他引:1  
本文采用P5709从硫酸介质中萃取镉(Ⅱ)。确定了其萃取机理及萃合物组成,并用红外光谱确证;测定出表观萃取平衡常数Kex=10~(1.29),讨论了影响萃取的有关因素。  相似文献   

10.
固相微萃取技术的研究进展   总被引:3,自引:0,他引:3  
较为详细地综述了固相微萃取的仪器构造,原理,应用和发展前景,固相微萃取是近年来发展起来的一种无溶剂、简单、高效、经济的样品预处理方法,与传统的溶剂萃取技术相比具有许多突出的优点,目前已被应用于环境 药物分析等方面。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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