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电感耦合等离子体原子发射光谱(ICP-AES)法与内标法的结合扩展了ICP-AES法的分析范围。采用氢氧化钠熔融样品,ICP-AES-内标法测定各类水泥标准物质样品中SiO_2、Al_2O_3、TFe_2O_3、MgO、TiO_2等氧化物的含量。实验结果表明,标准物质测定值与标准值吻合,6次平行样品测定相对标准偏差小于1.4%。方法一次熔样,纵向测定主常量元素,操作简单,快速,准确,为水泥标准物质的研制提供了另一种定值方式。 相似文献
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A new conserved quantity is deduced from Mei symmetry of Tzenoff equations for holonomic systems. The expression of this new conserved quantity is given, and the determining equation to induce this new conserved quantity is presented. The results exhibit that this new method is easier to find more conserved quantities than the previously reported ones. Finally, application of this new result is presented by a practical example. 相似文献
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仿生超润湿材料是指类似自然界中生命体具有的特殊浸润界面性质的一类材料。近20年来,研究人员通过模仿自然,揭示了一系列超润湿界面材料的构建机理,设计制备了多种仿生超润湿材料,并将这些具有特殊表面浸润性能的材料拓展应用到了国防、军工、航空航天、建筑、农业、医疗、海洋防污等众多领域。本文首先介绍表面润湿现象的基础理论,接着从仿生的角度出发,介绍了以仿荷叶、鱼鳞、沙漠甲虫、猪笼草为代表的几种拥有不同表面浸润性能的材料,并总结了这几种材料的仿生设计原理、结构与性能的关系以及所面临的问题。综述了近年来仿生超润湿材料在防污抗菌、防雾防霜防覆冰、油水分离等方面的应用进展,最后展望了仿生超润湿材料的发展方向。 相似文献
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Zhenzhen Wang 《中国物理 B》2022,31(12):126801-126801
We report comprehensive investigations into the structure of high-quality (111)-oriented SrRuO3 films on SrTiO3 substrates to elucidate the effect of (111) heteroepitaxial strain. We found that SrRuO3 film with a thickness of ~ 40 nm is compressively strained in plane on the substrate with full coherency. Nevertheless, the out-of-plane spacing is almost the same as in the bulk, which is at odds with the conventional paradigm. By probing a series of half-order Bragg reflections using synchrotron-based x-ray diffraction combined with analyses of the scanning transmission electron microscopy images, we discovered that the heteroepitaxial strain is accommodated via significant suppression of the degree of c+ octahedral tilting and the formation of three equivalent domain structures on the (111) SrTiO3 substrate. This anomalous effect sheds light on the understanding of an unconventional paradigm of film-substrate coupling for the (111) heteroepitaxial strain. 相似文献
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In situ angle dispersive synchrotron X-ray diffraction and Raman scattering measurements under pressure are em- ployed to study the structural evolution of Cu4Bi4S9 nanoribbons, which are fabricated by using a facile solvothermal method. Both experiments show that a structural phase transition occurs near 14.5 GPa, and there is a pressure-induced re- versible amorphization at about 25.6 GPa. The electrical transport property of a single Cu4Bi4S9 nanoribbon under different pressures is also investigated. 相似文献
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煤炭资源型城市可持续发展的综合评价方法研究 总被引:1,自引:0,他引:1
"环境与发展"是21世纪时代的主题,全方位、多视角研究煤炭资源型城市的可持续发展是研究我国区域社会经济持续发展的重要内容和前提条件.提出了基于因子分析法和DEA方法相结合的资源型城市可持续发展能力的评价方法,并以鸡西市为例,选取1995到2006年作为决策单元,评价了该市12年的可持续发展状况,并用理想点法对有效年限进行排序.结果表明:2001年是个转折点,鸡西市从2002年开始各年相对前几年都有效,在DEA有效的年份中2004年排名最后,因此,要增加城市的可持续发展能力,必须突出系统性、整体性原则. 相似文献
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Continuously Doping Bi2Sr2CaCu2O8+δ into Electron-Doped Superconductor by CaH2 Annealing Method 下载免费PDF全文
As a typical hole-doped cuprate superconductor, Bi2Sr2CaCu2O8+δ(Bi2212) carrier doping is mostly determined by its oxygen content. Traditional doping methods can regulate its doping level within the range of hole doping.Here we report the first application of CaH2 annealing method in regulating the doping level of Bi2212. By continuously controlling the anneal time, a series of differently doped samples can be obtained. The combined experime... 相似文献
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氟代丙烯酸酯三元共聚物细乳液的合成与表征 总被引:17,自引:1,他引:17
在低乳化剂用量和不加助乳化剂的条件下,采用细乳液聚合方法,合成了平均粒径在110~150nm的氟代丙烯酸酯(FA)、甲基丙烯酸甲酯(MMA)及甲基丙烯酸丁酯(BMA)三元共聚物乳液.利用GPC,FTIR及1HNMR谱表征了共聚物分子量和结构组成,采用激光光散射法研究了聚合过程中粒径变化规律,通过接触角方法对共聚物表面性能进行了表征.结果表明,油溶性引发剂AIBN引发FA-MMA-BMA三元细乳液共聚合的主要成核场所为单体液滴.即每个单体液滴都是一个独立的微型反应器,可避免因为单体水溶性的差异而使共聚组成产生漂移.细乳液聚合合成含氟共聚物乳液的分子量分布窄(1.3~1.5),乳液稳定性能好,共聚物在低含氟量下即表现出优异的疏水疏油性能. 相似文献