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1.
为了探究固液相微界面作用的物质输移机制,丰富水-沙-污染物微界面作用的数值模拟方法,本文基于光滑粒子流体动力学方法(SPH)耦合电场力、布朗运动力、曳力等弱作用力,构建复杂微界面作用模型,模拟了细颗粒泥沙吸附Pb2+的微界面作用过程.模拟结果演示了细颗粒泥沙与Pb2+的微界面作用全过程,Pb2+进入液膜,由液膜迁移至颗粒内,逐渐填满液膜和孔道,最终填充空腔.微界面作用动力学分析结果表明模拟结果符合准二级动力学模式;微界面作用模式识别结果表明0~10min为膜扩散阶段,10~60min为膜扩散和颗粒内扩散并存阶段,60~210min为颗粒内扩散阶段.模拟结果具有较好的微界面作用动力学相似性和微界面作用模式一致性.该方法适用于微米尺度下的微界面作用过程模拟,为水-沙-污染物交互作用的微观尺度建模提供新思路.  相似文献   

2.
用溶胶凝胶法制备了全丙基-β-CD气相色谱柱,得到了和对应静态柱相当的柱效,并和静态法色谱柱做了对Grob试剂和某些苯系位置异构体分离性能方面的比较.结果显示,这两种方法制备的毛细管气相色谱柱有相似的分离性能.初步探索了用溶胶凝胶法涂渍非端羟基固定相气相色谱毛细管柱的机理,说明了溶胶凝胶前体所形成的三维网状结构对固定相有裹挟作用,这种裹挟作用是固定相涂渍成功的关键因素.  相似文献   

3.
旋流分离器油水分离机理的数值分析   总被引:1,自引:0,他引:1  
采用计算流体动力学(CFD)的数值方法研究旋流分离器内的速度场分布,空气柱的产生、发展过程以及油滴粒子的运动轨道,探讨油水旋流分离器的分离机理.模拟结果表明:油水旋流分离器内的流场是三维非对称分布的;空气柱的产生和发展是负压和对流传输共同作用的结果;油滴粒子在径向力、轴向力以及周围湍流脉动流场的共同作用下作随机运动,部分粒子由溢流管排出而得到分离;通过计算溢流管排出的油滴粒子数与进入旋流分离器的油滴粒子总数之比可得到油水旋流分离器的分离效率.模拟结果为进一步研究旋流器特性参数对分离效率的影响和旋流器的结构优化提供了参考.  相似文献   

4.
利用“点击反应”合成了咪唑嵌合半胱氨酸硅胶固定相SIL-AVI-Cys,并通过热重、红外光谱以及元素分析对材料进行了表征.填充SIL-AVI-Cys色谱柱在分离胞核嘧啶、胞苷、肌苷、尿嘧啶和尿苷等5种亲水性化合物时表现为亲水作用模式,而在分离苯胺和苯酚类物质时则可表现出亲水/反相混合模式特征.通过考察流动相pH值、盐浓度对分析物保留的影响,进一步探讨了该固定相的分离机理.流动相pH值的改变可通过改变分析物的离子化影响其与固定相之间的作用力及其保留行为.流动相中盐浓度的增加,可减弱酸性分析物的保留,而对于碱性和中性分析物则无显著影响.此外,SIL-AVI-Cys色谱柱的分离性能采用酰胺及核酸碱基/核苷类物质进行了表征,并将其进一步应用于奶粉中三聚氰胺的表征和检测.  相似文献   

5.
研究了γ-氯丙基键合胶这种弱极性键合相作为色谱固定相在甲醇/水流动相体系下的柱效,动力学曲线及反相性能,显示其良好的色谱性能,以及在对前列腺的分离测定中,有效好的结果。  相似文献   

6.
针对微波腔内不均匀电磁场导致的微波加热不均匀现象,利用金属对微波具有反射的特点,将导电粒子与运动物料相结合,研究了随机运动导电粒子对微波转筒干燥腔内电场分布的影响.利用EDEM与COMSOL软件将运动场与电磁场相耦合,模拟导电粒子的尺寸、数量以及随机运动方式对微波腔内电场分布的影响.结果表明:直径小于20,mm的导电粒子对电场的影响较小;自由随机运动的导电粒子因粒子集聚而恶化微波腔内的电场分布;固定间距的随机运动导电粒子可提高微波腔内的平均电场强度及电场分布的均匀性.  相似文献   

7.
研究制备氯丙基功能化的有机-硅胶杂化整体柱,考察不同组成对整体柱聚合结构、渗透性、稳定性和柱效的影响,分析整体柱电渗流变化趋势和电色谱分离性能.所制备的氯丙基杂化硅胶整体柱结构稳定、固定相分布均匀,分离性能良好,包括反相色谱保留、静电荷吸附和电泳等多种模式的协同作用.应用加压电色谱模式,7种烷基苯、8种苯胺类化合物和7种苯甲酸类物质在氯丙基杂化硅胶整体柱中实现基线分离.  相似文献   

8.
建立C60-g-(乙二胺基)丙基键合硅胶填充柱毛细管电色谱法。研究操作条件如流动相组成、pH值对柱电渗流的影响.结果表明填充柱与流动相之间存在着快速平衡,可建立稳定的电色谱方法,并且填充柱可以在pH 2.5-7的范围内提供稳定的电渗流,有利于电色谱分离。  相似文献   

9.
用~(60)Co-γ辐射法制备载体型多孔芳类聚合物气相色谱固定相,考察了影响其色谱性能的主要因素.它与目前常用的多孔高分子小球固定相相比,柱效高,热稳定性好,未觉察到静电效应,对烷烃分离速度快,分离度高,色谱峰形对称.  相似文献   

10.
高小龙 《科技信息》2010,(24):I0085-I0086
本文研究了活性Al2O3微色谱柱分离锂(Li),使用原子吸收分光光度法(AAS)测定微量锂。改变实验条件,研究了柱径,洗脱方式对柱效的影响,活性Al2O3微色谱柱的吸附容量,吸附机理。  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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