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101.
102.
《Calphad》2014
Experimental investigations and Gibbs energy modelling of KCl–LiCl–UCl3 system employing CALPHAD method are reported. Gibbs energy modelling of the subsystems KCl–UCl3 and LiCl–UCl3 was carried out primarily using phase diagram data from the literature. For the Gibbs energy modelling of the KCl–LiCl subsystem, new phase boundary data corresponding to four terminal compositions , 0.05, 0.95 and 0.97) obtained through differential thermal analysis data along with thermochemical and phase diagram data from the literature were used. Thermal analysis was also carried out for KCl–LiCl eutectic mixture containing small amounts of UCl3 and ). The liquidus temperatures for these compositions were found to be 637 K and 674 K. Electromotive force data for dilute solutions of UCl3 in the KCl–LiCl eutectic melt, measured in the temperature range 708–833 K in the present work, were found to be in good agreement with the literature data. These data were also used as input for the Gibbs energy modelling of the KCl–LiCl–UCl3 system. In order to improve the quality of the resulting Gibbs energy functions of the quasibinaries and the quasiternary, enthalpies of mixing of the corresponding melts estimated using an empirical correlation based on surrounded-ion model were also used as input. Finally, the generated Gibbs energy functions were used to compute phase equilibria. 相似文献
103.
Sridhar Komarneni Bharat L. Newalkar Dongsheng Li Tarun Gheyi Christina L. Lopano Peter J. Heaney Jeffrey E. Post 《Journal of Porous Materials》2003,10(4):243-248
Several nitrate containing anionic clays were synthesized at different temperatures and the kinetics of NO3
– release were determined to test their suitability as slow-release N fertilizers. A sample (Mg:Al = 2:1) synthesized at 60°C with smaller particle size released 75, 86 and 100% of its NO3
– in 1, 3 and 7 days, respectively when equilibrated with a simulated soil solution. On the other hand, the 175°C/2 hrs sample with larger particle size released 65, 77 and 84% of its nitrate in 1, 3 and 7 days, respectively. Another anionic clay (synthesized at 175°C/24 hrs) of higher charge density (Mg:Al = 2:1) containing NO3
– was equilibrated with a 0.012 N NaCl or Na2CO3 to test the role of different anions in releasing the NO3
– anion from the interlayers. The results showed that Cl– released more NO3
– than did CO3
2– from this anionic clay after all the treatment times probably as a result of the CO3
2– anion blocking the release of NO3
– from the interior of the crystals. When a lower charge density (Mg:Al = 3:1) sample (synthesized at 175°C/48 hrs) was equilibrated with 0.02N solution of anions the release of nitrate was as follows: Cl– < F– < SO4
= CO3
2–. These results suggest that the divalent SO4
= and CO3
2– anions are more effective in the release of NO3
– from this lower charge density anionic clay. Time-resolved structural analysis of NO3
– exchange with CO3
2– in the above anionic clay using synchrotron x-ray diffraction showed that ion exchange is rapid because of small crystal size and lower charge density. Thus the release of NO3
– from anionic clays is an interplay among the type of anions present in soil solution, their concentration, pH of soil solution, the charge density and crystal size of anionic clay etc. 相似文献
104.
采用共形离子溶液模型(conformalionic solution model, CIS) 在二元熔盐体系相图的基础上,对三元熔盐体系LiNO3-NaNO3-KNO3进行了相图计算,得到该三元体系最低共熔点为117.7℃,相应的摩尔分数组成分别为x(LiNO3) = 0.375,x(NaNO3) = 0.075,x(KNO3) = 0.550。按照热力学最低共熔点计算结果,采用熔融法制备了三元硝酸熔盐,通过DSC和TG实验测定其最低共熔点为118.3℃,这与计算得到的结果(117.7℃)基本一致。TG测试结果表明当温度低于587.2℃时,该三元熔盐体系较为稳定,其工作温度范围为118.3~587.2℃,该三元硝酸熔盐适合在太阳能热发电中作为高温传热蓄热材料使用。 相似文献
105.
Advanced Sn/C composite anodes for lithium ion batteries 总被引:2,自引:0,他引:2
Metallic tin was deposited in fine particulate form on the surface of carbonaceous mesophase spherules (CMS) and in the pores of porous carbon by the decomposition and reduction of tin(II) 2-ethylhexanoate at 450 °C. The Sn/C composite powders obtained were used as anode materials for lithium ion cells. Electrochemical cycling tests of coin cells show that the dispersion of tin into the carbonaceous materials enhances the reversible capacity of the electrodes. The capacity retention at the 50th cycle is 91 % for Sn/CMS composite containing 22% tin, against 428 mAh g–1 at the first cycle. With further increase in tin content, the capacity fade upon cycling is more rapid. 相似文献
106.
改性硝酸铵的工业制备方法及其性能 总被引:2,自引:0,他引:2
硝酸铵饱和溶液中加入表面活性剂辛基三甲基溴化铵,采用真空膨胀结晶技术工业制备一种新型改性硝酸铵,并介绍其性能特点。 相似文献
107.
采用高温熔融法,在磷酸盐玻璃的配合料中引入抗菌剂硝酸银,一次熔化制得抗菌玻璃材料。通过对磷酸盐玻璃的抗菌性能和缓释性能分析,结果表明:制备抗菌磷酸盐玻璃,合适的银含量为1.5%~2.0%(质量),处理温度在1200~1350℃,即可获得良好的抗菌效果和缓释性。 相似文献
108.
采用电导法研究了水溶液中盐的浓度与其电导率的关系,根据模拟水样和实际水样在电导率与全盐量的关系上有较好的吻合性,介绍了电导法测定水中全盐量的方法,结果表明在低浓度范围内电导率与盐浓度成线性关系,与传统的重量法相比,具有快速、简便、准确度高的特点。 相似文献
109.
超重力反应结晶法纳米碳酸钙浆料及粉料的表面处理 总被引:3,自引:0,他引:3
研究了脂肪酸盐A、水溶性铁酸酯偶联剂B(B1)以及铁酸酯偶联剂C对新型超重力反应结晶法所得的纳米CaCO3浆料及粉料的湿法表面处理的配方与工艺,确定了A体系的最佳改性时间为30~40min、改性温度为40~50℃、改性剂用量(质量分数)为3%~5%;B(B1)体系搅拌强度必须很高,改性时间30~40min,改性温度80℃左右,改性剂用量(质量分数)3%~5%;C体系的最佳改性时间为30~40min,改性剂用量(质量分数)为3%~5%。同时,采用红外光谱对改性前后的纳米碳酸钙进行了表征,表明改性刑已连接至CaCO3表面。最后,用分散稳定模型简要分析了改性机理。 相似文献
110.
Yutaka Kagawa Yasuo Kogo Hiroshi Hatta 《Journal of the American Ceramic Society》1989,72(6):1092-1094
Thermal expansion behaviors of a Si3 N4 -whisker-reinforced sodaborosilicate glass matrix composite are studied. An abrupt increase of the coefficient of thermal expansion is observed and is attributed to formation of crystobalite in the sodaborosilicate glass matrix. This thermal expansion behavior is discussed with special reference to the phase transformation of the crystobalite. 相似文献