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991.
992.
以松香、二乙烯三胺、3-氯-2-羟基丙烷磺酸钠和硫脲为主剂合成了硫脲基松香咪唑啉季铵盐,对其结构进行了红外和核磁(~(13)CNMR)表征。通过静态失重法和电化学方法考察了硫脲基松香咪唑啉季铵盐在酸性介质中的缓蚀性能,结合成膜理论以及缓蚀剂的分子结构,对自制缓蚀剂的缓蚀机理做出了解释。结果表明:303 K下,在质量分数为15%的盐酸介质中加入占盐酸质量0.4%的硫脲基松香咪唑啉季铵盐,其缓蚀率可达90.81%;自制缓蚀剂吸附在碳钢表面形成吸附膜,从而起到缓蚀作用。 相似文献
993.
994.
《Ceramics International》2016,42(15):16916-16926
In recent years, multi-component integrated composite cathodes for lithium ion batteries have attracted considerable attention. In this work, novel layered-spinel integrated cathode materials of (1−x)LiNi0.5Mn0.5O2-xLiMn1.9Al0.1O4 were synthesized by a sol-gel method, and their phase structures, morphologies and electrochemical performance were investigated. The crystal structure of the (1−x)LiNi0.5Mn0.5O2-xLiMn1.9Al0.1O4 is changed from layered to spinel structure with increasing x. All the samples exhibit nanoscale grains with the minimum grain size of ~130 nm when x = 0.5. The composite electrode with x = 0.5 exhibits the optimal discharge capacity, presenting a large initial discharge capacity of 236 mAh g−1 at the current density of 20 mA g−1. Good rate capability is also obtained at the composite electrode with x = 0.5 where the electrode displays the relatively high discharge capacity of 64.9 mAh g−1 at the high rate of 5 C. The improved electrochemical performance is related to the introduction of spinel structure into layered structure and small grain size. The spinel structure can stabilize the layered structure, which leads to the improvement in the electrochemical performance of the composites; and the small grain size in the sample with x = 0.5 provides short lithium ion diffusion way and thus enhances the electrochemical performance. 相似文献
995.
《Ceramics International》2016,42(13):15005-15011
Disperse pure tetragonal zirconia (t-ZrO2) nanoparticles smaller than 10 nm are essential for preparation of structural and functional zirconia materials, but syntheses of t-ZrO2 nanoparticles using inorganic zirconium salts usually result in severe agglomeration. In this paper, we report a hydrothermal corrosion approach for improving the dispersity of t-ZrO2 nanoparticles synthesized by precipitation using zirconium oxychloride without any surfactants. Disperse pure t-ZrO2 nanoparticles with average sizes of 4.5 and 6 nm and size distributions of 2–11 and 3–12 nm were obtained by calcining precipitates at 400 °C for 2 h and 500 °C for 0.5 h followed by HCl corrosion at 120 °C for 75 h, respectively. Disperse t-ZrO2 nanoparticles with an average size of 6 nm and a size distribution of 3–12 nm were pressed into green compacts at 500 MPa and sintered by two-step sintering (heating to 1150 °C without hold and decreasing to 1000 °C with a 10 h hold). The sintered bodies are dense pure monoclinic ZrO2 nanocrystalline ceramic with a relative density of 99.9% and an average grain size of 110 nm. 相似文献
996.
Influence of FeO/SiO2 and CaO/SiO2 Ratios in Iron‐Saturated ZnO‐Rich Fayalite Slags on the Corrosion of MgO 下载免费PDF全文
Liugang Chen Muxing Guo Huayue Shi Peter Tom Jones Bart Blanpain Annelies Malfliet 《Journal of the American Ceramic Society》2016,99(11):3754-3760
The corrosion behavior of MgO in iron‐saturated ZnO‐rich fayalite (ZFS) slags having various FeO/SiO2 ratio and CaO/SiO2 ratio was investigated using MgO crucible tests for 12 h at 1200°C. The FeO/SiO2 and CaO/SiO2 ratios in the ZFS slags were varied from 1.0 to 2.2, and from 0.04 to 0.32, respectively. In all of the tests, it was observed that MgO dissolves into ZFS slags and that (Zn,Fe,Mg)2SiO4 olivine and (Zn,Fe,Mg)O solid solution are formed at the crucible/slag interface. The MgO dissolution decreased with the FeO/SiO2 ratio up to a value of 1.7 and then slightly increased, whereas it continuously increased with the CaO/SiO2 ratio. There is no obvious relationship between the amount of olivine and the FeO/SiO2 ratio or CaO/SiO2 ratio. In comparison, the formation of (Zn,Fe,Mg)O solid solution is enhanced by increasing the FeO/SiO2 ratio or CaO/SiO2 ratio in ZFS slags. The results suggest that MgO corrosion is the lowest for FeO/SiO2 and CaO/SiO2 ratios around 1.7 and 0, respectively. 相似文献
997.
998.
中东地区伊拉克新投产的H油田地表水资源有限,急需研究注海水工程配套技术,因此海水对注水管柱的腐蚀速率显得至关重要。以H油田注水系统环节涉及的6种挂片(碳合金、35Cr Mo、N80、L80、80ss、90s)为研究对象,以高温高压动态腐蚀仪为技术手段,研究了高温高压及离子浓度变化条件下的动态腐蚀速率情况,研究表明,碳合金、35Cr MO和N80属于尚耐蚀型材料,L80、80ss和90s属于完全耐蚀型材料,从技术经济较大考虑推荐L80和80ss管材。Cl~-、SO_4~(2-)和HCO_3~-浓度对腐蚀速率影响主次顺序为:Cl-HCO_3~-SO_4~(2-)。 相似文献
999.
1000.