水热合成温度及Na~+对二氧化锰晶型和形貌的影响

在水热条件下,以过硫酸盐和二价锰盐为反应物,用XRD和SEM技术研究了合成温度及Na+对二氧化锰晶体结构和形貌的影响规律.结果表明:反应温度低于100℃,在Na+存在下易生成γ-MnO2,形貌呈球形,结构致密,在其表面呈向外突出的丝状物.随温度升高,晶型均向β型转变,微球逐渐发生破裂.     

用二氧化锰制备超级电容器及其电化学性能研究

以KMnO4为锰源,在180℃水热条件下反应24 h可控制备了α-,β-,δ-MnO2,采用高分辨扫描电镜、X射线衍射研究了它们的微观形貌和晶型结构,并通过循环伏安、交流阻抗和恒流充放电比较了三者的电化学电容器性能,结果表明,在6 mol/L KOH电解液中δ-MnO2表现出最好的电容性能,当电流密度为1 mA/cm2时,比电容最大,容量高达162.78 F/g。     

低温常压液相法制备纳米MnO2

纳米二氧化锰是一种重要的无机功能材料.本文提出了一种在低温、常压条件下,以KMnO4和HCl为原料,在液相环境中制备纳米二氧化锰的新工艺,研究了反应温度、盐酸浓度、反应物摩尔配比以及反应时间对产物结构及粒径的影响,探讨了反应生长机理,并指出制备纳米δ-MnO2的最佳方案为:反应物盐酸浓度2mol/L,反应物摩尔配比KM...     

不同晶型的纳米二氧化钛的合成

对不同晶型纳米二氧化钛的合成方法和及其形貌控制作了简要综述．前驱体的种类和浓度，溶剂的极性，pH值，反应温度，添加剂等反应条件对所得纳米二氧化钛的晶型，颗粒大小及形貌有很大影响．通过选择不同种类的模板剂和控制反应条件可以制得具有不同晶型的介孔二氧化钛．     

纳米二氧化锰的合成研究

以高锰酸钾(KMnO4)、硫酸锰(MnSO4·H2O)和乙酸乙酯为反应起始原料,采用不同反应条件制备出了纳米二氧化锰.文章主要探讨了反应物料比、反应时间、反应温度等对产物形貌的影响,并通过扫描电子显微镜(SEM)、透射电镜(TEM)和XRD对二氧化锰进行了形貌和结构分析.电化学性能研究表明,在-0.2 V~0.4 V的电位范围内,MnO2表现出典型的赝电容特性.     

液相法制备纳米二氧化锰

以过硫酸钾（K2S2O8）和硫酸锰（MnSO4.H2O）为反应起始原料,采用液相法制备出了纳米二氧化锰。通过X-射线衍射（XRD）、傅里叶变换红外光谱（FTIR）、激光粒度分析仪等表征手段对所制备的产物进行分析和表征。主要考察了反应时间（t）、pH值以及反应温度（T）对产物结构和粒径的影响,从而找出液相法制备纳米MnO2的最佳反应条件。结果表明,在控制溶液pH值等于1,反应温度为60℃,反应时间为22 h的条件下,可以制得纳米级的纯四方晶系α-MnO2.     

TiO2纳米颗粒电化学后处理对超级电容器性能的改善

通过水热法以硫酸钛为钛源制备TiO2 纳米颗粒,然后将样品制成电极模拟超级电容器.1)通过SEM观察TiO2 纳米颗粒的微观形貌,其直径大小分布在30～50 nm, 并通过XRD测定TiO2 纳米颗粒的晶相结构为锐钛矿型;2)对超级电容器进行电循环处理,其比电容从10 mF/cm2增长到103 mF/cm2,并达到稳定,说明电循环处理大幅度提高了该样品的电导率;3)CV曲线中观察到一对明显的氧化还原峰,其比电容主要起源于该氧化还原反应. 恒流充放电和CV曲线计算所得比电容基本一致,阻抗谱图谱也清晰地显示了氧化还原反应所对应的极化电阻的存在.     

硫化铋纳米晶的水热合成及表征

在低温水热条件下,以BiCl3、Na2S2O3(或Na2S、硫脲)为反应物,制备了硫化铋(Bi2S3)纳米晶.用X射线粉末衍射(XRD)、扫描电镜(SEM)及纳米粒度测定仪对样品的结构及形貌进行了表征分析.结果表明,所得样品为正交晶系的Bi2S3纳米晶,形貌主要为纳米棒;同时硫源、反应温度及反应时间会影响样品的粒径.     

铝钴掺杂对Ni（OH）2结构的影响

以NiSO4、Al2(SO4)3、CoSO4为原料,采用化学沉淀法分别制备铝、钴单独掺杂和复合掺杂的Ni(OH)2样品,利用XRD、EDS和SEM对产物的晶型结构、化学成分和微观形貌进行表征.结果表明:掺杂离子种类、数量及掺杂方式等因素对Ni(OH)2粉体的晶型结构、微观形貌均有较大影响.在掺铝量较低时样品为β-Ni(OH)2、α-Ni(OH)2混合相,当铝掺杂量(摩尔分数)大于10%时样品为单相的α-Ni(OH)2,微观形貌呈类球形;钴掺杂的样品为单相β-Ni(OH)2,微观形貌为纳米片构成的花瓣状微球,空隙清晰;Al/Co复合掺杂的样品为不规则层叠状结构的α-Ni(OH)2.     

纳米TiO_2的制备及其光催化性能的评价

采用钛酸四丁酯在酸性条件下水解生成溶胶、凝胶,进而将凝胶干燥、煅烧、研磨过筛,制成锐钛矿型TiO_2纳米晶。通过X射线粉末衍射、红外光谱、透射电镜等手段表征产品的组成、结构、形貌和粒径等。测定TiO_2纳米晶在紫外光条件下催化亚甲基蓝和甲基橙降解率,评价其光催化降解性能。实验结果表明,纳米TiO_2光催化降解亚甲基蓝和甲基橙的反应均符合一级动力学方程,且降解亚甲基蓝的反应速率常数明显高于降解甲基橙的速率常数。     

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.     

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.     

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.     

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.     

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.     

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.