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711.
烟气酸露点计算方法比较和分析 总被引:3,自引:0,他引:3
酸露点是锅炉设计和运行中重要参数之一,目前国内外计算烟气酸露点方法很多,但是不同方法计算结果差异较大.结合有关文献对几种计算烟气酸露点的方法进行了比较,分析了SO3浓度和水蒸气含量对烟气酸露点变化趋势的影响.研究结果表明,荷兰的A.G.Okkes公式和И.A.Bapahoba公式比较精确,前苏联热力计算酸露点经验公式、日本电力研究所经验公式和Haase & Borgmann公式的误差比较大.此外,对前苏联热力计算酸露点经验公式进行了修正. 相似文献
712.
《Ceramics International》2023,49(7):10342-10353
In this work, (75-x)B2O3-xTeO2-11Bi2O3–10Li2O-1Ho2O3-3Yb2O3 (x = 10–60 mol%) mixed glass former (MGF) glasses were prepared by using the melt-quenching method to investigate the effect of mixed glass former between B2O3 and TeO2 on the structural, optical and radiation shielding properties of glass. The amorphous nature of the glass samples was confirmed through XRD measurement. Optical ultraviolet–visible light (UV–Vis) spectroscopy revealed that the direct and indirect optical band gap (Eopt) decreased as TeO2 content increased except for the anomaly at x = 30 mol% due to the interchanging dominance of bridging oxygen (BO) and non-bridging oxygen (NBO) in the glass network. Both direct and indirect refractive indices, n posted an increment except for x = 30 mol% due to polarizability influence of BO and NBO. Urbach energy, Eu declined thus indicating lesser disorder and less defects on the glass structure. The radiation shielding properties of the glass samples were determined for 15 keV–15 MeV photon energy range by using Phy-X/PSD software. Atomic number-dependent parameters such as mass attenuation coefficient (MAC) and effective atomic number (Zeff) demonstrated an enhanced performances caused by higher Z of Te over B. Meanwhile, density-dependent parameters such as linear attenuation coefficient (LAC), mean-free path (MFP), half-value layer (HVL) and tenth-value layer (TVL) all exhibited an improvement over TeO2 concentration due to higher density data obtained. 相似文献
713.
Jiahui Zhang Chengwei Gao Chengmiao He Linling Tan Shiliang Kang Qing Jiao Tiefeng Xu Changgui Lin 《Journal of the American Ceramic Society》2023,106(1):354-364
Chalcogenide solid-state electrolytes (SSEs) have been receiving growing attentions due to their high ionic conductivity and suitable mechanic properties, especially the Li2S–P2S5 systems incorporated with a second glass network formers (Si, Ge, Sn, and so on) besides P. Although the ionic conductivities are generally enhanced with the second glass network formers, the comprehensive effects of different glass formers on other properties, including electrochemical, cycling, and air stability, remain elusive. To acquire deeper understanding, herein, three common but representative glass network formers (SiS2, GeS2, and SnS2) were introduced into Li2S–P2S5, and their individual effects were investigated systematically. The results of multiscale characterizations before and after lithium stripping/plating cycling confirmed that the introduction of metal cations (Ge, Sn) generally leads to worse electrochemical stability and shorter cycle life of these SSEs toward lithium metal compared with SSEs with nonmetal cation (Si) modification. However, the air stability is related to the binding energy of M–S (M = Si, Ge, Sn), which is consistent with the hard base soft acid theory. This work provides valuable understanding for designing pragmatic Li2S–P2S5–MS2-based SSEs with high electrochemistry, cycling, and air stability. 相似文献
714.
《Journal of the European Ceramic Society》2023,43(8):3447-3453
Producing ceramic asymmetric membranes usually requires several steps to prepare macroporous support and then the selective layer deposition. This process is energy and time-consuming, which is expensive. In this sense, the one-step centrifugal casting technique is an interesting alternative. Therefore, this work aimed to prepare ultrafiltration ceramic membranes by the centrifugal casting method, investigating the effect of a pore-forming agent on membrane performance. Different concentrations of activated carbon were used in the alumina suspension, and then the tubes were molded, dried, and sintered. The membranes' shrinkage, morphology, apparent porosity, hydraulic permeance, and BSA protein retention were evaluated to identify the effect of using the pore-forming agent. The membrane prepared without activated carbon rejected 91% of the BSA molecules (66 kDa), indicating its molecular weight cut-off. Using more than 2.5% of activated carbon increased the porosity and hydraulic permeance of the membranes, but at the expense of low BSA retention. 相似文献
715.
Xuefei Ke Xiaowei Wang Yadan Wang Xiaoming Ren Haizheng Tao 《Journal of the American Ceramic Society》2023,106(12):7449-7459
By using the aerodynamic levitation and laser melting technique to well extend the glass-forming region into the Mg-rich and peraluminous regime, a series of magnesium aluminosilicate glasses were prepared to investigate the Mg and Al mixed effects on thermal properties, including glass transition temperature (Tg), crystallization behavior, and thermal stability. With the gradual substitution of Mg by Al, Tg exhibits two types of near-linear rises with different slopes in two compositional regions separated by r = 0.57, where r is equal to the molar ratio of [Al2O3]/([Al2O3] + [MgO]). Moreover, when it comes to other properties, that is, crystallization behavior and thermal stability, this critical point precisely appears at the same r = 0.57. Compared to the slower increase of Tg in Mg-rich region, the steeper rise of Tg in the peraluminous region is mainly ascribed to the step-by-step formation of oxygen triclusters driven by Pauling's second rule. Moreover, the occurrence of the critical point for Tg rise at r = 0.57 rather than the theoretical 0.5 can be seen as a proof of the role of Mg cations partly as a network former. 相似文献