菱锰矿与石英浮选行为及其机理研究

研究了十二胺对菱锰矿与石英分离的浮选行为,以及调整剂水玻璃和六偏磷酸钠对菱锰矿和石英浮选的影响.结果表明,在pH=7～12时,十二胺对两种矿物都具有良好的捕收性;水玻璃和六偏磷酸钠均抑制石英而活化菱锰矿.人工混合矿浮选表明,在pH=7时六偏磷酸钠为调整剂,菱锰矿与石英可浮性相当,不可分离.紫外分光光度法结果表明,Mn2+在pH=7时可与石英发生静电吸附.红外分析结果显示,水玻璃可吸附于石英和菱锰矿表面,六偏磷酸钠可吸附于菱锰矿表面.     

硅藻土、钠长石及石英的可浮性研究

实验考察了十二胺对硅藻土、钠长石、石英的捕收能力.通过ζ-电位、红外光谱检测对十二胺与硅藻土、钠长石、石英的作用机理进行了分析.浮选实验结果表明,pH为5.5~10.5,十二胺浓度为2.38×10-4mol/L时,钠长石和石英单矿物浮选回收率分别在92%和97%以上,而硅藻土的回收率在5%以下.ζ-电位分析结果表明,pH为5.5~10.5时,十二胺在钠长石和石英表面的吸附明显强于在硅藻土表面的吸附,这与浮选结果一致.红外光谱分析结果表明,pH为5.5时,十二胺在硅藻土、钠长石、石英表面均存在物理吸附、氢键作用,且在硅藻土表面的吸附强度相对弱,导致其可浮性差.     

硅藻土、钠长石及石英的可浮性研究

实验考察了十二胺对硅藻土、钠长石、石英的捕收能力.通过ζ-电位、红外光谱检测对十二胺与硅藻土、钠长石、石英的作用机理进行了分析.浮选实验结果表明,pH为55～105,十二胺浓度为238×10-4mol/L时,钠长石和石英单矿物浮选回收率分别在92%和97%以上,而硅藻土的回收率在5%以下.ζ-电位分析结果表明,pH为55～105时,十二胺在钠长石和石英表面的吸附明显强于在硅藻土表面的吸附,这与浮选结果一致.红外光谱分析结果表明,pH为55时,十二胺在硅藻土、钠长石、石英表面均存在物理吸附、氢键作用,且在硅藻土表面的吸附强度相对弱,导致其可浮性差.     

十二胺体系中异极矿浮选行为的研究

以十二胺为捕收剂,通过单矿物浮选试验对异极矿的可浮性及正辛醇对异极矿可浮性的影响进行了初步研究.结果表明,当pH值在10~11范围内,适量的十二胺对未经活化的异极矿具较好的捕收性;正辛醇对异极矿不具有捕收性.正辛醇能够强化十二胺阳离子在异极矿表面的吸附,降低十二胺的浮选起始浓度;当正辛醇以25%的物质的量比取代十二胺组成胺醇复合捕收剂时,使用复合捕收剂可获得与使用十二胺相同的浮选效果.     

氢化松香酯基阳离子捕收剂M--N的合成及浮选性能

以石英纯矿物浮选回收率和季铵盐活性物含量为指标,进行了摩尔比、温度、时间等合成条件的优化.以酒钢焙烧磁铁矿实际矿石在捕收剂M-N作用下进行脱硅反浮选,所得铁精矿品位56.54%、回收率77.33%.在5~30℃ 条件下,浮选精矿指标稳定,耐低温性优良.捕收性能优于传统药剂十二胺和醚胺.Zeta电位和红外光谱分析表明,M-N在石英表面发生静电吸附作用和氢键作用,因此加强了浮选分离的效果.     

十二胺浮选黄锑矿的作用机理

利用单矿物实验,研究了十二胺(DDA)对黄锑矿的浮选行为.研究发现:pH值为2.0~8.0时,黄锑矿浮选回收率达到90%以上;pH值为8.0~10.0时,黄锑矿浮选回收率急剧降低;当pH值>10.0时,十二胺对黄锑矿几乎没有捕收作用.十二胺浮选溶液化学分析结果表明,十二胺阳离子(DDA+)是对黄锑矿产生捕收作用的主要成分.采用密度泛函理论研究了黄锑矿晶体以及十二胺离子和分子的电子结构性质,考察了十二胺离子、十二胺分子和水分子在黄锑矿表面的吸附行为.三种吸附质在黄锑矿表面吸附能顺序为DDA>H2O>DDA+,十二胺离子可排开黄锑矿表面的水化膜,实现黄锑矿的疏水上浮,十二胺离子主要通过物理吸附形式吸附于黄锑矿表面.     

胺类捕收剂对铝硅矿物的浮选性能研究

通过浮选实验、动电位测定、红外光谱测试、结构/性能及量化计算,研究了十二胺、N,N-二甲基十二胺、N-十二烷基-1,3-丙二胺三种药剂的结构和物化性质,讨论了它们对高岭石、叶腊石和伊利石的表面电性及浮选行为的影响.结果表明:胺类化合物易阳离子化,在铝硅矿物表面主要发生了静电吸附,多胺和叔胺在矿物表面吸附后,能显著改变矿物的ζ—电位;当药剂分子中引入亚氨基,药剂与矿物的氢键作用也变为明显;药剂所含N数越多、N上烃基越多,药剂的阳离子化趋势越强;基团电负性、浮选剂特性指数、水油平衡度和疏水链长等物化参数表明胺类捕收剂对铝硅酸盐类矿物捕收性能的决定因素是极性基的特性,而因为高岭石晶体的特殊性,疏水链长对其在微酸性、中性和微碱性条件下捕收有特别的影响;捕收矿物的能力为多胺>叔胺>脂肪伯胺;应用于铝土矿反浮选以N-十二烷基-1,3-丙二胺为最佳.     

胺类捕收剂对铝硅矿物的浮选性能研究

通过浮选实验、动电位测定、红外光谱测试、结构／性能及量化计算，研究了十二胺、N，N-二甲基十二胺、N-十二烷基-1，3-丙二胺三种药剂的结构和物化性质，讨论了它们对高岭石、叶腊石和伊利石的表面电性及浮选行为的影响．结果表明：胺类化舍物易阳离子化，在铝硅矿物表面主要发生了静电吸附，多胺和叔胺在矿物表面吸附后，能显著改变矿物的ζ-电位；当药剂分子中引入亚氨基，药刑与矿物的氧键作用也变为明显；药剂所含N数越多、N上烃基越多，药剂的阳离子化趋势越强；基团电负性、浮选剂特性指数、水油平衡度和疏水链长等物化参数表明胺类捕收剂对铝硅酸盐类矿物捕收性能的决定因素是极性基的特性，而因为高岭石晶体的特殊性，疏水链长对其在微酸性、中性和微碱性条件下捕收有特别的影响；捕收矿物的能力为多胺〉叔胺〉脂肪伯胺；应用于铝土矿反浮选以N-十二烷基-1，3-丙二胺为最佳．     

N，N-二(3-氯-2-羟丙基)十二胺对菱镁矿浮选脱硅性能的影响

通过浮选实验研究了N，N-二(3-氯-2-羟丙基)十二胺(NCDA)作用下石英、菱镁矿和白云石的浮选行为.通过zeta电位测试、基团电负性判据和量子化学计算等分析研究了NCDA的性能及作用机理.浮选实验结果表明:在矿浆自然pH值条件下，加入同等用量的捕收剂，NCDA对石英的捕收能力比十二胺(DDA)强，对菱镁矿和白云石的捕收能力明显弱于DDA.zeta电位测试结果表明，NCDA与石英表面发生静电吸附和氢键作用.基团电负性、水油度和前线轨道能计算结果表明，相比DDA，NCDA具有更好的捕收性能和起泡性能，更容易与石英表面发生相互作用.     

铝硅酸盐矿物捕收剂的设计研究

铝硅酸盐矿物是层状硅酸盐矿物,破碎后晶体端面荷电是表面原子的选择性吸附和解离而成,并随pH变化而变化,其层面荷电为金属离子的晶格取代造成,荷永久负电荷,不随溶液pH值变化而改变.阳离子捕收剂是铝硅酸盐矿物捕收剂的设计首选.多胺类药剂与十二胺相比增加了吸附活性点,浮选性能得到改善.有关参数的计算结果说明多胺类药剂是比十二胺更佳的铝硅酸盐矿物捕收剂.浮选试验也证实这一结论.     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Design and analysis of generic LBS application developing platform

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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