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101.
The lithium metal battery has attracted considerable attention as the ultimate lithium secondary battery for high energy density. However, safety issues and battery performance deterioration due to the growth of lithium dendrites have hampered the practical use of lithium metal batteries. Recently, lithium fluoride has been considered as a lithium metal protective layer to solve this problem. In this review, firstly, the results of the studies on dendrites and SEI that have been carried out to date are reviewed. Secondly, the results of studies on lithium fluoride are divided into additive, artificial SEI, and other methods and the possibilities of their practical use are discussed. Finally, the significance and limitations of the lithium fluoride studies are summarized, and general conclusions and prospects for recommended research directions to accelerate the commercialization of lithium metal batteries are presented. 相似文献
102.
Samira Lotfian Tommy Vikström Andreas Lennartsson Bo Björkman Hesham Ahmed Caisa Samuelsson 《Canadian Metallurgical Quarterly》2019,58(2):164-176
Shredder residue materials are produced after the removal of ferrous and non-ferrous fractions from end-of-life electronic equipment. Despite the high plastic content and metal value in the ash, high percentages of these materials are currently sent to landfills. In this study, the potential of utilising shredder residue material and other plastic-containing materials as reducing agents was studied. Plastic-containing materials were co-injected with coal into a zinc-fuming furnace in Boliden-Rönnskär smelter. The data obtained from the trial, such as the data from the chemical analysis of the slag and the steam production, are discussed. The observations indicate that plastic-containing material can replace up to 1?ton?h?1 of coal without a significant decrease in the zinc reduction rate. 相似文献
103.
104.
受环保压力影响,西乡公司生产水泥用河道淤沙供应紧张,难以满足生产需求且价格上涨幅度较大,严重影响到水泥生产及成本,我们开展了磁铁尾矿在水泥中的应用研究工作,通过连续几个月的生产实践,对物料配比优化,磨机技术改造,实现利用磁铁尾矿与石灰石双掺解决混合材紧缺问题,降低了水泥生产成本,水泥质量及性能稳定。 相似文献
105.
Alkali metal ion substitution is an effective strategy to improve the luminescence properties of phosphors. In this work, a series of red-emitting phosphors Na1-xLix/2Kx/2La0.6Eu0.4MgWO6 were prepared by a traditional high-temperature solid-state reaction. Their phase structure, microstructure, luminescence properties and potential application in phosphor-converted white light-emitting diodes (pc-WLEDs) were investigated in detail. X-ray diffraction (XRD) result revealed the formation of a solid solution when x?≤?0.3, which kept monoclinic structure of NaLaMgWO6. Photoluminescence investigation indicated that the partial substitution of Li+/K+ ions for Na+ ions improved largely the red emission of Eu3+. Based on the optimized Na0.7Li0.15K0.15La0.6Eu0.4MgWO6 sample with relatively good thermal stability, a WLED device was fabricated by combining a near-ultraviolet (NUV) chip (~400?nm) with the phosphor mixture of commercial green/blue phosphors and the optimized red phosphor. The results indicated that the optimized red phosphor in this work could be a potential candidate for WLEDs pumped by NUV chips. 相似文献
106.
物质平衡-拟压力近似条件法确定气藏储量 总被引:5,自引:3,他引:2
物质平衡法作为一种有效的手段被广泛应用于气藏储量或井控储量的确定。为简便准确地确定气藏储量,笔者从物质平衡原理出发导出了"物质平衡条件",求解气体渗流数学模型,得到了"拟压力近似条件"。将二者结合,提出了"物质平衡-拟压力近似条件法"(MB-QAC方法)。利用该方法,通过边界控制流阶段(产量波动相较于边界作用可忽略)的生产数据便可准确地计算气藏储量。定产量、定流压以及复杂生产计划条件下的数值模拟数据以及气藏实例验证了其有效性。在生产数据记录可靠的条件下,储量计算误差一般小于5%。同时,数值模拟结果表明,动态物质平衡方程是一种近似关系,拟压力近似条件对于模拟的各种情形均成立。由于考虑了岩石和束缚水的压缩性、气井产量的波动和气体性质的变化,MB-QAC方法具有一定的理论基础,对于异常高压和正常压力系统的气藏均适用,但不适用于水体活跃的气藏。 相似文献
107.
采用TC4和ER2319焊丝直流/变极性冷金属过渡实现异种金属电弧增材制造,通过金相显微镜、扫描电镜、透射电镜、能谱、硬度试验、纳米压痕以及拉伸试验等方法对钛/铝构件界面组织特征与力学性能进行分析.结果表明,在钛合金表面堆积铝合金时,只有少量的钛合金熔化,钛原子扩散到液态铝合金中,形成不同长度的TiAl3金属间化合物.10 μm左右的反应层在钛/铝界面形成.邻近钛侧的反应层均匀连续,靠近铝合金一侧的反应层呈现长条状或块状.界面反应层的显微硬度介于钛合金和铝合金显微硬度之间.构件的最高抗拉强度为111 MPa. 相似文献
108.
Ehsan Yaghoubi Mahdi M. Disfani Arul Arulrajah Jayantha Kodikara 《Soils and Foundations》2019,59(2):443-457
Despite extensive research on the behavior of unsaturated fine-grained materials, there is still a lack of understanding of the volumetric behavior of unsaturated granular materials. In this research, a model has been developed to predict the fundamental volumetric behavior of unsaturated granular materials through loading and wetting state paths. In this regard, a loading-wetting surface was developed in a space of void ratio-moisture ratio-net stress. A distinctive feature of the proposed model is the relative simplicity in obtaining the model parameters using conventional geotechnical testing equipment. Two types of recycled granular materials, commonly applied in unbound pavements were used, namely, recycled crushed brick (CB) and excavation waste rock (WR). The uniqueness of the developed surface was evaluated by employing a number of loading and wetting state paths. The results indicate that the developed surface is unique in its loading state paths; however, it only shows uniqueness in its wetting state paths for stress levels greater than 2000 kPa. The proposed model seeks to introduce the application of the unsaturated soil mechanics theory, for predicting the behavior of granular materials in the field, by providing a practical and cost-effective methodology. 相似文献
109.
110.
Alafara A. Baba Daud T. Olaoluwa Ayo F. Balogun Abdullah S. Ibrahim Fausat T. Olasinde Folahan A. Adekola 《Canadian Metallurgical Quarterly》2019,58(2):232-240
This study examines the extraction of beryllium and aluminium from a Nigerian beryl ore using Cyanex®272 in kerosene from an aqueous sulphate pregnant solution. Parameters such as extractant concentration and equilibrium pH that dictates the extraction yield were studied. Under the following conditions: temperature 27?±?2°C, phase ratio 1?1, about 45.50 and 46.76% of beryllium and aluminium were extracted by 0.15?mol?L?1 Cyanex®272 concentration within 30?min. However, the extraction yield of beryllium and aluminium was increased to 91.68% and 97.89% at equilibrium pH of 3 and 4, respectively, for beryllium and aluminium at 27?±?2°C. A 0.05?mol?L?1 H2SO4 solution was found to be adequate for the stripping of about 99.00% Be and 95.40% Al from the loaded organic phase. The pure solutions containing metal ions were accordingly beneficiated to obtain beryllium and aluminium compounds of industrial values. 相似文献