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1.
用二氯化锡和NaY沸石为原料,经浸渍、焙烧等工序制备SnO2/NaY光催化剂,通过X射线粉末衍射、透射电镜和紫外可见漫反射光谱表征显示:尺寸在20~60二氧化锡纳米棒在NaY沸石表面上形成;以紫外光为光源,对甲基橙溶液进行光催化降解以检验其光催化性能,结果表明:该催化剂具有紫外光催化活性.  相似文献   

2.
以钛酸四丁酯和NaY沸石为原料,通过浸渍、焙烧等工序制备出TiO2/NaY复合光催化剂,经X射线粉末衍射、透射电镜和紫外可见漫反射光谱表征显示,在沸石表面上形成了粒径5~7 nm二氧化钛粒子;该催化剂对亚甲基蓝溶液的降解呈现紫外光催化活性.  相似文献   

3.
用钛酸四丁酯和NaY沸石为原料,经浸渍、焙烧等工序制备出TiO2/NaY复合催化剂。通过X射线粉末衍射及透射电镜表征,结果显示:在NaY沸石表面上形成了二氧化钛粒子(尺寸5~7nm)。以紫外光为光源,对甲基橙溶液的光催化性能进行检验,证实该催化剂具有紫外光催化活性。  相似文献   

4.
用硝酸铋、偏钒酸铵和NaY沸石为原料,经浸渍、焙烧等工序制备出BiVOJNaY光催化剂。通过X射线粉末衍射、透射电镜表征,结果显示:在NaY沸石表面上形成了尺寸为7nm的钒酸铋纳米粒子。光催化降解甲基橙实验表明,BiVOJNaY比BiVO4具有更高的光催化活性。  相似文献   

5.
以钛酸四丁酯、AgNO3和NaY沸石为原料,通过浸渍、焙烧、离子交换等工序制备出TiO2/AgY复合材料.制备的复合材料具有抗大肠杆菌功能,在紫外光照射下,该材料可以将大肠杆菌完全氧化分解.  相似文献   

6.
用正电子湮没寿命谱学的方法研究微量水对KCl在NaY沸石中扩散的影响, 实验分别测量了有吸附水与脱水后担载量为10%的KCl/NaY寿命谱.所有寿命谱经4个寿命分量分解,其中三、四寿命分量分别对应β笼与超笼微环境状态.实验表明在无水常温条件下KCl不能自发地在NaY沸石中扩散,微量水对KCl在NaY沸石中扩散有非常明显的影响.  相似文献   

7.
刘粤丽  朱光中 《江西科学》1993,11(4):252-258
介绍了NaA、NaY和ZSM-5等重要沸石的工业合成.讨论了合成中的化学、技术及经济等因素.此外,还描述了SiCl_4脱铝和沸石的成型等过程.  相似文献   

8.
通过考察实验影响因素以在最佳条件合成一种具有潜在应用价值的高水热稳定性材料。通过降解NaY分子筛形成其前驱体,以CTMABr(十六烷基三甲基溴化铵)为模板剂合成介-微孔分子筛。XRD和FT IR表征结果表明材料的孔壁含有沸石结构单元,在750?℃,100%水蒸汽中处理2?h后介孔结构依然存在。研究认为在最佳条件下合成的材料是一种高水热稳定性的孔壁含有沸石结构单元的介孔材料,且与直接制备分子筛前驱体的过程相比,降解微孔分子筛制备前驱体有沸石回收和成本低廉两方面的优点。  相似文献   

9.
通过考察实验影响因素以在最佳条件合成一种具有潜在应用价值的高水热稳定性材料。通过降解NaY分子筛形成其前驱体,以CTMABr(十六烷基三甲基溴化铵)为模板剂合成介-微孔分子筛。XRD和FT-IR表征结果表明材料的孔壁含有沸石结构单元,在750℃,100%水蒸汽中处理2h后介孔结构依然存在。研究认为在最佳条件下合成的材料是一种高水热稳定性的孔壁含有沸石结构单元的介孔材料,且与直接制备分子筛前驱体的过程相比,降解微孔分子筛制备前驱体有沸石回收和成本低廉两方面的优点。  相似文献   

10.
对以NaY为原料、用水热脱铝法制备超稳Y沸石(USY)过程中钠离子交换深度、超稳化过程的温度和压力对USY性质的影响进行了研究.结果表明,Al—O键在500℃水热条件下可以较快地水解.钠离子可以阻止脱铝反应.当超稳化处理温度升高时,脱铝深度增加,USY的酸量下降.超稳Y沸石的结晶度随超稳化压力的增加而降低.高硅铝比的超稳Y沸石具有好的热稳定性和抗积炭性.通过调节超稳化处理过程中的控制因素而改变USY的硅铝比,可对表面酸性产生有效的调变作用.  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.
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.  相似文献   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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。  相似文献   

18.
19.
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  相似文献   

20.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

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