邻甲苯胺在银纳米棒生长中作用的探讨

探讨了邻甲苯胺在制备银纳米棒中的作用.在邻甲苯胺存在下利用乙醇还原硝酸银制备了银纳米棒.产物经过XRD、TEM表征.对比实验表明不加邻甲苯胺或当邻甲苯胺形成配合物(2-(2-甲基苯基)氨基-4-(2-甲基苯基)亚氨基-2-戊烯)后,在类似条件下得到银纳米粒子.     

TiO_2纳米棒阵列的水浴法制备及形貌控制

展示一种在FTO玻璃基底上直接生长TiO2纳米棒阵列的简单方法.利用化学水浴法,通过控制反应过程中钛源和盐酸(HCl)量,在FTO导电玻璃基底上直接生长分布均匀的TiO2纳米棒阵列,棒的高度约为500nm,直径约为20nm.纳米棒阵列薄膜在退火之前为无定型结构;经过450℃退火0.5h后,为锐钛矿和金红石的混合相.     

单晶钛酸铅纳米棒的可控水热合成研究

以不同浓度的聚乙烯醇(PVA)和聚丙烯酸(PAA)作为添加剂,利用水热合成法成功制备出具有不同直径的钛酸铅纳米棒.X射线衍射(XRD)结果表明纳米棒为四方相纯钙钛矿结构.透射电子显微镜(TEM)研究表明,随着PVA浓度的升高,纳米棒的直径变小,长度变短,纳米棒在产物中所占比例提高;当在反应物中同时加入少量的PVA和PAA时,能合成直径近乎高浓度PVA作用下的纳米棒.高分辨透射电子显微镜(HRTEM)分析表明纳米棒为单晶结构,且纳米棒主要沿着[100]方向生长.     

ATO纳米棒的水热法制备及其性能

以SnCl4·5H2O和SbCl3为原料,采用水热法制备了锑掺杂氧化锡(ATO)纳米棒,产物的电阻率约为100Ω·cm.通过扫描电镜(SEM)、X射线衍射(XRD)、能谱(EDS)对产物的形态结构进行表征,结果发现,随着反应时间的延长,ATO纳米棒直径不变,长度逐渐增大,长径比(L/D)逐渐增大;随着反应物SnCl4浓度的升高,ATO纳米棒的直径和长度均增大,L/D基本不变.简单阐述了ATO纳米棒的形成机理,并对反应条件对纳米棒L/D的影响进行了探索.     

水热法Na2SeSO3歧化反应制备单质硒纳米棒

在HAC-NaAC组成为1：1的缓冲溶液中，以聚乙烯醇为导向剂，通过Na2SeSO3的歧化作用生成无定形硒前驱体，对前驱体进行水热处理合成单质硒纳米棒。通过表征表明所制得产物结构为三方相硒纳米棒，并且形貌稳定、产率高，它的平均直径为30～80nm，长度可达到170～1100nm。     

ZnSe/聚合物纤维纳米复合物结构及发光特性

将甲基丙烯酸甲酯、甲基丙烯酸丁酯、丙烯酸三元共聚物与聚丙烯腈共混,通过静电纺制得聚合物纳米纤维;将Zn2+通过配位与聚合物中的羧酸根阴离子结合,与NaHSe溶液中的Se源反应,在聚合物纳米纤维表面生长出ZnSe纳米粒子.使用场发射扫描电子显微镜、X射线光电子能谱(XPS)、荧光光谱仪对ZnSe/聚合物纳米复合材料进行表征,结果表明,ZnSe纳米粒子直径为20～60 nm; Zn与Se的原子数之比为 3∶1;在波长为260 nm的光激发下,ZnSe/聚合物纤维纳米复合材料发射光谱的峰值为396 nm,与ZnSe的本征发射带468 nm相比,产生了约70 nm的蓝移.     

以AAO模板为基底可控合成一维碳纳米材料

将不负载任何活性组分的阳极氧化铝模板分别放入两段炉中,700℃下催化裂解乙炔可控合成一维碳纳米材料,反应气氛分别为氩气和氢气;产物通过扫描电子显微镜和高分辨透射电子显微镜进行了表征.结果表明:当反应气氛为氩气时,第一段炉中模板表面为相互缠绕的蠕虫状的碳纳米管,其直径在100nm左右,模板孔内为开口的碳纳米管,其直径约为50nm左右;第二段炉中模板表面沉积了密集的碳纳米棒,其形貌规整,棒体很直,散落在模板表面,粗的直径约200nm,细的约100nm,长度短的不到1μm,长的约2.5μm;当反应气氛为氢气时,模板表面沉积了规整的直立碳纳米棒,其长度长的约1μm,短的约为100nm,粒径约为50nm.所合成的碳纳米棒为实心的断断续续的石墨片层组成的波纹状结构.     

低温水热制备ZnO纳米棒及其生长机理

以Zn(NO3)2·6H2O为前驱体,在碱性环境中,低温水热方法直接制备了ZnO纳米棒.应用场发射扫描电子显微镜(FESEM)、能谱仪(EDS)和X射线衍射仪(XRD)对样品进行了表征;通过光催化降解亚甲基蓝来评价ZnO的光催化活性;对60℃,1～24 h范围内不同水热样品,进行了形貌观察,分析了ZnO的形核过程.结果表明:ZnO为六边棱柱状纳米棒,晶型为纤锌矿结构;ZnO纳米棒的表观生长速率约为0.7μm/h,表观形核时间约为3 min;碱性条件是影响形核的重要因素;光催化活性随水热时间的增加而增强.     

溶胶-凝胶-水热法制备Na0.5Bi0.5TiO3单晶纳米棒的研究

采用溶胶-凝胶-水热法在一定条件下合成单晶Na0.5Bi0.5TiO3纳米棒.该方法能够很好地控制产物的组分,避免高温晶化过程中Na或Bi离子的挥发.利用XRD、SEM、TEM和紫外/可见吸收光谱等分别对产物的物相、形貌、微结构以及光吸收等性质进行表征.结果表明获得的产物为三方相钙钛矿结构,NBT纳米棒与NBT粗晶材料...     

MnO2纳米棒的水热制备及表征

以MnCl2·4H2O和KMnO4为主要反应物,通过简单的水热方法合成了MnO2纳米棒,所得产物用粉末X射线衍射（XRD）、扫描电镜（SEM）进行了表征。在水热反应过程中,反应时间和反应浓度对纳米棒的形成有重要的作用,在MnO2纳米棒催化过氧化氢降解亚甲基蓝过程中表明其具有催化性能。     

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