钛酸钠纳米线的合成和结构

利用TiO₂粉末和NaOH水溶液在175℃～240℃水热反应得到了具有层状结构的钛酸钠纳米线。研究了原料比例和反应温度的影响。利用X射线粉末衍射、电子显微术和X射线能量色散谱等结构分析手段研究了纳米线的微观结构。观察到纳米线内部存在大量畴界和缺陷。发现上述钛酸钠纳米线的结构与任何已知结构都不相同,初步标定为单斜结构,单胞参数为a=2.15nm, b=0.377nm, c=1.28nm, β=103.5°。进一步用上述纳米线和KOH溶液水热反应合成了钛酸钾(K₂Ti₈O₁₇)纳米线。     

Na0.5Bi0．5TiO3纳米线的制备及其光致发光特性研究

采用溶胶-凝胶-水热合成技术,以钛酸四丁酯、醋酸钠和五水硝酸铋为原料,NaOH为矿化剂,合成了直径约10～20 nm,长度达到微米量级的钙钛矿结构钛酸铋钠纳米线单晶. 通过X射线衍射仪,透射电子显微镜,X射线光电子能谱等技术对纳米线的形貌和成分进行了表征,并研究了Na0.5Bi0.5TiO3纳米线的光致发光特性.     

PbTiO_3纳米线的合成及其光致发光特性研究

采用水热合成技术,以钛酸四丁酯和三水醋酸铅为原料,NaOH为矿化剂,合成了直径约12nm的钙钛矿结构钛酸铅纳米线.通过X射线衍射,扫描电子显微镜,X射线光电子能谱等技术对纳米线的形貌和成分进行了表征并研究了PbTi O3纳米线的光致发光特性.     

水热合成PbTiO_3纳米线

采用水热法合成了纯钙钛矿钛酸铅纳米线.实验采用醋酸铅[Pb(AC)2.3H2O],钛酸四丁酯[Ti(OC4H9)4]为原料,氢氧化钠为矿化剂,研究了不同水热反应温度对产物物相及形貌的影响.当温度为200℃,反应48h,可以生成直径为10nm左右,长度在几百纳米到几微米之间的纯钙钛矿钛酸铅纳米线.     

两步法仿生合成TiO2纳米线及其表征

以钛酸正四丁酯及L-半胱氨酸为钛源和模板剂,醇热法仿生合成纳米TiO2前体,冉将前体与氢氧化钠溶液水热反应制备出TiO2纳米线．通过SEM、XRD、FTIR以及比表面积及孔径分析仪对前体及纳米线进行表征,结果表明：TiO2纳米线为无定型的钛酸盐结构,直径在20～40nm,长度达数微米,其比表面积为312．58m2／g;煅烧后TiO2纳米线由无定型转变成锐钛矿型结构,FT—IR图谱分析表明纳米线含有Ti—O键．     

化合物LaCo2Al8的晶体结构及其Rietveld精修

利用X射线粉末衍射技术和Rietveld结构修正方法对LaCo2Al8进行了研究,结果表明,化合物LaCo2Al8具有正交CaCo2Al8结构类型,空间群为Pbam(№.55),点阵参数为α=1.252 711(4)nm,b=1.441 71(5)nm,c=0.404 22(1)nm,指标化的可靠性因子为152.0(4...     

基于多孔氧化铝模板的勃姆石纳米线的形成

使用高纯铝箔作为初始原料,以多孔阳极氧化铝模板为中间产物,通过对多孔阳极氧化铝模板进行水热反应的方法制备出勃姆石（γ-AlOOH）纳米线,产物的特征长度为60 nm,直径在2～5 nm之间。整个实验方法简单,且没有引入其他杂质元素。分析了反应过程及水热反应温度和时间对勃姆石纳米线形貌的影响,并通过对比实验表明AAO模板的纳米多孔结构是水热反应生成勃姆石纳米结构的必要条件和主要原因。     

ZnS和C60纳米线阵列的构筑和表征

以多孔氧化铝为模板,通过水热反应制备出ZnS 和 C₆₀纳米线阵列,分别用透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线衍射(XRD)、拉曼光谱以及选区电子衍射图谱(SAED)等,对纳米线阵列形貌和化学成分进行表征.结果表明,ZnS 和C₆₀纳米线均为有序阵列.ZnS纳米线为多晶结构,在波长332 nm紫外光激发下, 发射519 nm特征荧光.同时介绍了水热条件下,在多孔氧化铝模板中填充目的产物,以及制备纳米线有序阵列的相关过程.该方法具有一定的普适性.     

多金属氧酸盐纳米线的制备表征及独特性质

在适当表面活性剂存在下，利用低温固相反应首次制备多金属氧酸盐纳米线，并用红外、透射电镜、X射线粉末衍射等手段进行表征。结果表明纳米线长为1－2μm，平均直径为20nm。此外多金属氧酸盐纳米线还具备其他一维纳米材料所不具有的特殊表面形貌。     

乙醇助水热法制备钛酸铋光催化剂的研究

以Bi(NO3)3·5H2O和Ti(SO4)2为反应物,用乙醇助水热法制备了钛酸铋光催化剂,并研究了水热温度、水热时间对样品光催化活性的影响.用X射线衍射表征了样品的结构,紫外可见漫反射光谱测试显示含有Bi12TiO20的样品吸收带发生了红移,比表面积及孔结构分析表明样品的比表面积远远高于化学溶剂分解法制备的钛酸铋的比表面积.以甲基橙为模拟污染物,评价了样品的光催化性能,发现当水热反应温度为140 ℃、水热反应时间为1.5 h时,样品的光催化活性最高.     

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.     

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.     

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.     

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.     

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.