TiO_2粉末制备方法的研究及表征分析

本文用非极性条件下溶胶—凝胶法、极性溶剂条件下溶胶—凝胶法、钛盐水解法、沉淀法四种不同的方法制备出TiO2无定型粉末．经400℃热处理2小时TiO2微细粉末全部为锐钛矿结构，经550℃热处理2小时，TiO2粉末为锐钛矿和金江石混合结构．以X—射线衍射（XRD）、透射电镜（TEM）、比表面积测定仪等手段对不同方法制备的微细粉末进行微观结构、粒径、比表面积等进行测定，并对四种制备方法的优劣性加以分析．     

超声波强化均匀沉淀法制备纳米TiO2

为了改善纳米TiO2的分散性能和细化其颗粒尺寸,采用超声波强化均匀沉淀法制备纳米TiO2.首先以工业级硫酸氧钛为原料,用均匀沉淀法制备纳米TiO2,通过对比试验来反映超声波对于制备纳米TiO2的影响.然后采用BET比表面积与孔隙度分析、扫描电子显微镜、透射电子显微镜、X射线衍射分析研究了超声波的强化作用.试验结果表明:超声波的强化作用具有明显的细化颗粒尺寸的作用;能增加纳米TiO2的比表面积、孔容积与孔径;能改善分散度,使颗粒粒径分布范围变窄.通过均匀沉淀过程能直接获得纯锐钛型纳米TiO2,而无需经过特定温度的煅烧定型,超声波作用对产物晶型无影响.     

纳米TiO_2固载脂肪酶及其固载界面表征

以3种不同形貌的纳米TiO2为载体固定化脂肪酶,研究载体形貌、酶添加量、pH值、温度和时间对固载酶活性的影响.研究结果表明,纳米线形貌TiO2固定化效果最好,最优固定化条件为加酶量0.25g/25mL溶液、pH 7.0、固载温度40℃、固载时间6.3h.利用SEM、XRD、FT-IR等对固载酶及其界面进行表征,SEM和XRD结果表明,脂肪酶吸附于纳米线TiO2载体表面,且未改变纳米线TiO2的晶型结构;FT-IR表征表明固载酶含有脂肪酶的特征吸收峰;比表面积分析显示固定化后样品的BET明显减小,表明脂肪酶在纳米线TiO2表面进行物理型吸附.     

介孔TiO2的结构分析

研究了热处理过程中介孔TiO2的结构及晶粒尺寸、比表面积间的相互关系,为纳米结构材料的定量研究奠定了基础借助G W Shere的圆柱通孔模型,将有孔氧化物视为立方结构体,通过比表面积、孔径、密度等参数的计算,对介孔TiO2的微结构进行了分析,结果说明其高比表面积主要来自于纳米晶和孔结构两者共同作用并在晶粒尺寸、比表面积、孔容之间建立了定量关系模型,不仅解释了其比表面积的变化规律,也使得预测孔结构数据成为了可能。     

TiO2/竹炭复合体光催化材料的孔隙结构及分布

采用比表面积及孔径分析技术,测定了浸渍法制备的TiO2/竹炭复合体光催化材料的氮吸附等温线,进而运用BET理论计算了其比表面积、总孔容积和平均孔径分别为359.81 m2/g、0317 2 cm3/g和3.526 nm。同时,依据BJH模型分析了其中孔的孔隙结构参数和孔径分布。结果表明：经过纳米TiO2改性的竹炭不仅保留了竹炭固有的孔隙结构,而且其比表面积、孔容积、孔径都有所增加。经纳米TiO2改性制备的光催化材料的中孔孔容积比竹炭提高了65.86 %。     

超纯水对溶剂合成纳米TiO_2粒径的调控及其表征

以钛酸四丁酯和甘氨酸为钛源和模板剂,研究超纯水的添加量对溶剂热法合成纳米TiO2粒径的影响,来调控纳米TiO2粒径.并通过SEM、EDS、XRD、FT-IR以及N2吸附-脱附实验对产物进行了形貌、结构及成分的表征.结果表明,SEM表征表明超纯水的添加量对TiO2纳米粒子粒径形成有较大影响,当超纯水的添加量为3.5mL时,制备的纳米TiO2最小粒径小于10nm;EDS表征表明其Ti∶O原子百分比为1∶1.89;XRD表征表明其为锐钛矿型单晶;FT-IR表征表明其含有典型的Ti-O键,且比表面积及孔径分析表明其比表面积和平均孔径分别为109.444m2/g和37.087nm.研究结果证明,通过调节超纯水的添加量可以有效控制TiO2纳米粒子的粒径.     

以梳型聚合物为模板制备介孔Ag/AgBr/TiO_2纳米复合材料

以钛酸四丁酯为钛源,梳型聚合物为模板,采用溶胶-凝胶法低温水浴制备具有介孔结构的纳米TiO2,通过沉积-沉淀法将Ag/AgBr负载于介孔TiO2纳米微粒表面,制得高比表面积的Ag/AgBr/TiO2纳米复合材料。采用XRD,TEM,N2吸附-脱附和UV-vis DRS等方法对Ag/AgBr/TiO2纳米复合材料进行了表征。结果表明,所制备的纳米TiO2和Ag/AgBr/TiO2纳米复合材料具有介孔结构;Ag/AgBr的引入,减小了介孔TiO2的比表面积(由346m2/g减小为253m2/g),但大幅度提高了其可见光催化活性。在可见光下,Ag/AgBr/TiO2降解甲基橙的速率分别为商品TiO2P25和介孔TiO2的145倍和60倍。     

非水相一步合成TiO2纳米晶及其光催化性能

利用正丁醇与TiCl4反应,在非水溶剂和无表面活性剂的条件下,通过改变反应物TiCl4与丁醇的摩尔比制备了纯锐钛矿TiO2纳米粒子和金红石TiO2纳米棒.利用X射线衍射分析、拉曼光谱分析、透射电镜和比表面积测定等测试分析手段对样品进行了表征,并以罗丹明B的脱色降解为模式反应,考察了样品的光催化性能.结果表明:所制备的纳米级TiO2比表面积大、晶粒尺寸小、结晶性完好,具有比商用P25更好的光催化活性.     

硫酸浓度对纳米级SO4^2-／TiO2固体超强酸的影响

用锐钛型纳米TiO2制备了纳米级SO4^2-／TiO2固体超强酸，分析了硫酸浓度不同时其比表面积、失重率、红外光谱及催化活性的不同。当硫酸浓度为1．0mol／L时，它在450～900℃的失重率为3．3％，比表面积为105．2m^2／g，对乙酸和丁醇酯化反应的酯化率达到98．4％。玻璃球负载纳米级SO4^2-／TiO2固体超强酸的重复使用性能好，在乙酸和丁醇的酯化反应中重复使用9次后的酯化率才由初次的99．3％变为84．9％。     

硫酸钛水解制备TiO2纳米粒子载荷添加剂

以硫酸钛为前驱体 ,采用溶胶凝胶超临界干燥法制备TiO2 纳米粒子润滑油载荷添加剂。采用红外光谱、BET氮容量吸附、透射电镜、热重差热分析、X 射线衍射等手段对TiO2 纳米粒子的特性进行了表征 ,分析了制备过程中的各种影响因素。结果表明 ,采用强烈搅拌、匀速滴加絮凝剂、控制反应终点的 pH值以及用乙醇为介质进行超临界干燥的方法制备出的TiO2 纳米粒子的平均粒径为 15～ 2 0nm ,比表面积约为 10 0m2 /g ,其结构为锐态型 ,表面有微量水和乙醇吸附。     

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