羧甲基纤维素钠对纳米Fe_3O_4在石英砂中迁移的影响

为提高纳米四氧化三铁(MNPs)在悬浊液中的稳定性,强化其在多孔介质中的迁移能力,实验选用羧甲基纤维素钠(CMC)修饰MNPs,通过zeta电位、颗粒粒径和沉降曲线的变化考察了修饰前后的MNPs在模拟地下水溶液中的稳定性,并通过一维柱实验考察了修饰前后的MNPs在石英砂介质中的迁移性能.结果表明:由于CMC对MNPs的修饰增大了MNPs表面的负电荷电量,有效抑制了MNPs的团聚,从而使得MNPs在CMC溶液中的稳定性远高于其在背景模拟地下水溶液的稳定性,相应作用也使得CMC修饰下的MNPs在石英砂介质中的迁移性能大大增强.     

表面活性剂二次包覆制备Fe3O4水基磁流体

以化学共沉淀法制备了Fe3O4磁性微粒,并以油酸为内层表面活性剂,分别以乳化剂-10(OP-10)、吐温-20(T-20)、壬基酚聚氧乙烯醚(Oπ-10)三种非离子型表面活性剂进行外层包覆,制备得到了双层表面活性剂修饰的Fe3O4水基磁流体。通过研究pH值、表面活性剂包覆温度、种类及用量对磁流体分散稳定性和磁性的影响,得到了能获得最佳性能的磁流体的实验条件,并用透射电镜(TEM)、红外光谱、磁化率曲线进行表征,证明该条件下制得的二次包覆的Fe3O4磁流体饱和磁化率强度高且能在水中稳定分散。     

不同修饰磁性纳米粒子生物安全性比较

 为了研究不同表面修饰的磁性纳米粒子（MNPs）的细胞毒性作用,评价其生物安全性,选用小鼠成纤维细胞（L929）,使用MTT比色法,对3-氨基丙基三乙氧基硅烷（APTS）修饰和溴化双十二烷基二甲基铵修饰的两种磁性纳米粒子不同剂量、时间对细胞的影响进行研究。结果发现,不同修饰的两种MNPs的浸提液的毒性分级试验中,APTS修饰的MNPs主要为1级,2级,合格;而高浓度DMAB修饰的MNPs的浸提液在48h组中为4级,有较强的毒性。MNPs的体外细胞毒性检测显示,APTS修饰的MNPs与DMAB修饰的MNPs相比,对细胞的生存率抑制较小。结果表明,APTS修饰的磁性纳米粒子生物相容性更好,磁性纳米粒子在不同剂量、时间对细胞毒性表现出一定的差异,存在一定程度的剂量、时间依赖性,且对细胞增殖抑制较低。     

叶酸/β-环糊精修饰的磁性纳米药物载体的合成及表征

采用共沉淀法在水相中合成表面修饰氨基的磁性纳米粒子(MNPs),进一步在其表面接枝叶酸(FA)修饰的β-环糊精衍生物(β-CDs),制得一种新型药物载体材料(FA-β-CDs-MNPs),并通过核磁共振光谱(1 H NMR)、红外光谱(FTIR)进行了结构表征。透射电镜(TEM)、X-射线衍射(XRD)、磁性能(VSM)分析表明:该纳米复合材料的尺寸为16nm左右,近似圆形且分散性能良好,用振动磁强计测得其具有超顺磁性,饱和磁化率为58emu/g,是潜在的肿瘤细胞靶向型药物载体材料。     

表面修饰的金纳米棒的生物相容性和细胞摄取研究

制备了棒状纳米金颗粒并对其表面进行了修饰,研究了其生物相容性以及运载荧光物质进入细胞的功能.所制备的材料通过聚乙二醇稳定、采用双修饰的方法获得了具有活性-NH2基团存在、稳定性好且生物相容性高的表面修饰的金纳米棒.采用透射电子显微镜和紫外可见吸收光谱对表面修饰的金纳米棒进行了表征,运用MTT比色分析法通过细胞毒性研究了表面修饰的金纳米棒的生物相容性,用流式细胞仪和激光共聚焦显微镜考察了其运载荧光物质进入细胞的功能.结果表明,表面修饰的金纳米棒具有良好的生物相容性,具有作为荧光物质或药物载体的应用前景,可应用于疾病的诊断治疗.     

基于γ-Fe_2O_3磁性纳米微球的MSPE研究

采用共价修饰方法得到海藻酸钠修饰的γ-Fe_2O_3@SiO_2-NH2-AA纳米粒子,用X-射线衍射法确定γ-Fe_2O_3的结构,用IR对纳米粒子γ-Fe_2O_3,γ-Fe_2O_3@SiO_2-NH2和γ-Fe_2O_3@SiO_2-NH2-AA进行结构确证.结果表明,氨基化和多糖化修饰成功.在静电相互作用下,利用γ-Fe_2O_3@SiO_2-NH2-AA纳米粒子对罗丹明B进行磁固相萃取,并对其进行优化.     

钛酸钡粉体的表面包覆与电子陶瓷改性

为实现改性杂质与钛酸钡粉体的均匀混合，达到对材料微结构、相结构和电学特性的准确控制，对水热纳米晶钛酸钡粉体进行了改性杂质的非均匀形核表面淀积包覆．文中利用包覆Y（OH），后的钛酸钡粉体在水中的毛细管浸润性得到改善、以及两种工艺方法制备的粉体在液一固分离离心过程中离心转速对液一固分离率的影响，判断Y（OH），对钛酸钡粉体的包覆效果；探讨了掺杂工艺对Y掺杂钛酸钡陶瓷半导化和室温电阻率的影响，以及用非均匀形核表面淀积包覆工艺制备的陶瓷PTCR和细晶介质陶瓷的性质．润湿性实验显示，利用表面淀积包覆工艺确实能获得良好的包覆效果．     

表面修饰纳米氧化锆的制备与表征

本文初步研究了丙烯酸对纳米氧化锆陶瓷粉体的表面修饰作用及其对粉体在丙酮中分散性和稳定性的影响，采用TEM、TG和FT-IR对表面修饰后的纳米氧化锆结构和表面特性进行了表征和研究，TEM分析结果说明用丙烯酸进行表面修饰大大改善了纳米氧化锆在丙酮中的分散性；TF-IR分析证实了修饰后的纳米氧化锆表面确实存在修饰剂的有机官能团，可能是因为丙烯酸中的羧基(-COOH)与纳米氧化锆粉体颗粒表面的羟基(-OH)发生了脱水酯化反应，TG结果给出氧化锆粒子表面键合的丙烯酸的质量百分比。     

超临界CO_2抗溶剂方法修饰碳纳米管

为增加碳纳米管与高分子材料的相容性,增强其在树脂共混体系中的稳定性,用超临界CO2抗溶剂沉积方法将PCL包覆到碳纳米管的表面,以阻止其分散后再次团聚,该方法对多壁碳纳米管和单壁碳纳米管均适用.探讨了CO2压力和PCL浓度与碳纳米管修饰效果之间的关系,为碳纳米管修饰提供了有效方法.     

单基包覆火药界面粘结强度研究

该文提出了一种改善单基包覆火药界面粘结强度的方法，其工艺过程如下：（１）将单基火药吸收增塑剂进行表面预处理；（２０进行包覆，制备了用增塑剂ＮＧ和ＤＢＰ进行表面预处理的２种单基包覆火药，与直接包覆的单克包覆火药作对比，进行老化和落锤冲击试验，测试其界面粘结强度。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to