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1.
表面活性剂辅助溶剂热方法合成PbS纳米立方微晶的研究   总被引:2,自引:0,他引:2  
借助表面活性剂辅助溶剂热方法合成了PbS纳米立方微晶,在合成过程中采用正丁醇与水构成溶剂,S2-由硫代乙酰胺在120℃分解提供.X-射线晶体衍射分析(XRD)表明产物属立方晶体,能谱分析(EDS)显示该样品存在Pb与S两种元素,二者比例为1∶1,并对PbS纳米立方微晶的形成机理进行了探讨。  相似文献   

2.
刺山柑多糖为刺山柑中主要成分,对其表征结构进行研究十分必要.采用扫描电子显微镜、粒径电荷分析仪、差式扫描量热仪、X-射线衍射仪及刚果红实验探讨了CSPSI-C的表征结构.结果表明,CSPSI-C为鳞片状、棒状及枝链状形态.并得到了其粒径和Zeta大小.热力学分析显示了CSPSI-C的热力学特性,X-射线衍射表明CSPSI-C为无定形态,刚果红实验提示CSPSI-C具有多股螺旋结构.研究了CSPSI-C的表征结构,为进一步研究其构效关系奠定基础.  相似文献   

3.
以硫代乙酰胺为硫源,采用一步溶剂热合成S掺杂TiO_2催化剂,以水中六价铬为污染物模型,考察S-TiO_2在可见光下的催化活性.采用X-射线光电子能谱、X-射线粉末衍射、紫外-可见吸收光谱、傅里叶变换红外光谱、荧光发射光谱和N2吸附-脱附等技术对S-TiO_2进行表征.结果表明,硫原子以S6+形式取代TiO_2晶格中的Ti~(4+),形成Ti-O-S键;S-TiO_2对六价铬的可见光还原率均高于TiO_2.适量硫掺杂可降低催化剂的荧光发射光谱强度,提高了光生载流子的利用率,使得S-TiO_2的光催化活性增强.  相似文献   

4.
采用溶剂热方法,以硫脲(TU)为硫源,CdCl2·2.5H2O、CdSO4·8H2O、Cd(Ac)2·2H2O为镉源,在相同的条件下合成了CdS纳米晶,掌握了不同镉源对产物物性和形貌的影响,并对溶剂热原位生长做了初步讨论.通过X-射线衍射(XRD)分析表明了产物均是六方相CdS,电子扫描电镜(SEM)展示了产物的形貌变化.利用溶剂热原位生长法改变产物的形貌,结果显示:产物结晶性提高、形貌均由纳米颗粒状转变为纳米棒状.  相似文献   

5.
以高炉钛渣和废玻璃为主要原料,在添加少量辅料的基础上研制矿渣微晶玻璃。研究中优化玻璃配方,采用反光显微镜、X-射线衍射和电镜,对样品进行显微结构分析,获得性能优良的矿渣微晶玻璃。可推荐建作材装饰和化工耐腐蚀管道的功能结构材料。  相似文献   

6.
采用聚乙二醇对异辛基苯基醚(Triton X-100)/正戊醇/环己烷/水溶液所形成的微乳液体系,控制合成出了四方晶系BaMoO4微晶,考察了微乳液中水与表面活性剂物质的量之比和反应物浓度对产物形貌的影响。采用扫描电子显微镜(SEM)、X-射线衍射(XRD)分别对产物的结构、粒度和形貌进行了表征。结果表明,在微乳液体系中,控制不同的实验条件,可以成功地合成蝴蝶结状以及不同长度树枝状的BaMoO4微晶,并且粒径分布集中,无团聚现象。论文还对不同形貌BaMoO4微晶的形成机理进行了初步探索。  相似文献   

7.
微凝胶模板法制备PNIPAM/PbS有机-无机复合微球   总被引:5,自引:2,他引:5  
采用反相乳液聚合方法合成了包埋有Pb2 的PNIPAM微凝胶,利用微凝胶的限域和导向作用,通过外源沉积法制备了PNIPAM/PbS有机 无机结构型复合微球.采用扫描电镜(SEM)、X射线衍射分析和热重分析对复合微球的形貌、无机沉积物PbS的晶型和相对含量等进行了表征.结果表明,高分子微凝胶的三维网络结构和所采用的制备方法确保了有机 无机复合材料复合的均匀性;微凝胶的模板作用使得复合材料呈现球状结构,微球的大小决定于模板的尺寸;复合微球中PbS具有面心立方结构;复合微球中无机物含量约为10%.实验所得PNIPAM/PbS复合微球明显兼有无机物的刚性和有机物的柔性.  相似文献   

8.
以2-氯吡嗪和硫脲为原料进行巯基化反应合成中间产物2-巯基吡嗪,进而与氯乙酸反应合成了目标产物(吡嗪-2-硫代)-乙酸,并用红外、元素、质谱和X-射线单晶衍射对其结构进行表征和分析.  相似文献   

9.
通过液相膜反应法成功合成氧化亚铜微晶,利用X-射线衍射、扫描电子显微镜表征分析探究了还原剂种类、膜两边反应物浓度以及反应温度等反应条件对其尺寸、形貌、晶体结构的影响,并以活性艳红X-3B为模拟污染物,考察了其吸附-可见光催化脱色性能。结果表明,以葡萄糖作还原剂、铜离子与氢氧化钠初始浓度比为1∶3、还原温度为50℃时,通过膜反应法制备出的氧化亚铜为表面粗糙的正八面体结构,同时具有良好的吸附和可见光催化性能,对活性艳红X-3B的光催化脱色率可达70%。  相似文献   

10.
以自制的高固体分热固性丙烯酸树脂为基质,以醋酸铅、硫代乙酰胺等为原料,在丙酮和甲醇的水溶液中,简便地制备了平均粒径为13nm的在聚合物基体中单分散的PbS纳米粒子,并对Pbs/聚丙烯酸酯复合材料采用X-射线粉末衍射、透射电镜、紫外一可见光谱和红外光谱进行了表征。研究结果表明,金属离子首先与聚合物的羧基络合,生成硫化物纳米微粒后,聚合物又包覆在纳米微粒的表面形成保护层。  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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