首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 13 毫秒
1.
The available thermochemical data for silicate liquids and glasses indicate that the customary assumption of heat-capacity additivity is not valid, particularly for liquid silicates near 1000 K. Estimates are obtained for the heat capacities of KO0.3-SiO2, NaO0.3-SiO2, and CaO-SiO2 liquids. The excess heat capacity of mixing of alkali silicates at 1000 K is:
in units of cal mol−1 K−1. Analytical expressions are given for C ep for KO0.5-NaO0.5-SiO2 and NaO0.3-CaO-SiO2 liquids at 900 to 1800 K.  相似文献   

2.
尹海英  舒明勇 《广州化工》2014,(21):85-87,109
以攀枝花市大龙潭地区的硅藻土为原料,采用水热碱溶法,通过煅烧、碱溶、过滤、结晶等工艺制得硅酸钠。并通过正交试验研究了液固比、反应时间、煅烧温度、Na OH用量四个因素对硅酸钠模数的影响。结果表明,当液固比为3∶1,反应时间60 min,反应温度700℃,Na OH用量12 g时可制备出最佳模数为1.341的硅酸钠。  相似文献   

3.
The thermally stimulated polarization and depolarization current (TSPC/TSDC) technique was used to study Naplus; ion motion in phase-separated silicate glasses containing between 10.3 and 20 mol% Na2O. Generally, two TSDC peaks and a high-temperature background (HTB) current were observed. The two TSDC peaks were attributed to different types of Naplus; motion, i.e. a short-range reorientation process and a longer-range translational motion. Changes in the microstructure affected only the size of the larger TSDC peak located at higher temperatures.  相似文献   

4.
张红洪  张峻 《云南化工》2008,35(2):62-64
介绍了建设10万t/a工业液体水玻璃生产装置财务评价内容,经财务盈利能力分析、清偿能力分析和敏感性分析,做出财务评价结论。  相似文献   

5.
向小军 《广东化工》2009,36(9):34-35
针对传统湿法泡花碱生产工艺能耗大,投资高,操作复杂,人员素质高的特点进行优化,采用废气回用、自然沉降、回配系统等措施对其进行优化,新建车间不仅能耗能降低25%以上,大大降低投资成本、维护成本、劳动强度,而且对原材料石英砂的质量要求更加宽松。  相似文献   

6.
张浩勤 《化工设计》2002,12(2):23-25
分析研究硅酸钠的干燥特性,测定硅酸钠的干燥速率;探讨了穿流风速、风湿对干燥速率的影响;依据实验结果进行了工业放大,设计出穿流带式干燥机。实践证明,设备干燥效果良好,解决了长期困扰企业的产品结块问题。  相似文献   

7.
水玻璃是一种基础无机化工原料,在国民经济的发展过程中有着重要作用。阐述了与水玻璃相关的几组常见名词,介绍了其基本理化性质、用途及湿法和干法的生产工艺,并详细对比了这两种生产工艺的区别;提出了生产水玻璃所需原料规格和产房设备的要求;最后,总结了水玻璃的行业现状,展望了未来的发展趋势。  相似文献   

8.
吕亮 《江西化工》2000,(2):13-15
在分析国内外五水偏硅酸钠生产工艺的基础上,利用水溶液结晶法生产五水偏硅酸钠,具有设备简单,易于操作,生产稳定,投资省等优点。  相似文献   

9.
Data are given on electrical activation of water and the use of its alkaline fraction (catholyte) in the preparation of liquid sodium silicate, intended to accelerate the process and decrease the viscosity of the resulting product. As a consequence, the silicate melting rate increased 2 times, and the viscosity decreased 1.5 times.  相似文献   

10.
The iron-nucleated devitrification of a sodium lead silicate glass was studied; it produces a glass-ceramic consisting of sodium metasilicate crystals in a lead silicate glass matrix. The nucleating agent is not incorporated in the crystal phase, Anisotropic devitrification of the glass in a thermal gradient produces an aligned microstructure with needles of sodium metasilicate oriented with the c axis parallel to the direction of crystallization.  相似文献   

11.
Nernst-Einstein Relation in Sodium Silicate Glass   总被引:1,自引:0,他引:1  
The diffusion coefficient and the electric mobility of sodium (22Na) ions in a sodium silicate glass (25 mol% Na2O) were measured simultaneously at 300°C in an experiment of the type used by Chemla, where the diffusion heat treatment is made in a constant dc electric field. The diffusion coefficient remained unchanged with an applied electric field. The correlation factor in the Nernst-Einstein relation calculated from the simultaneously measured diffusion coefficient and electric mobility was 0.5±0.05.  相似文献   

12.
本文首次将统计热力学的Weeks-Chandler-Anderson(简称WCA)微扰理论应用于非极性液体定容比热容和定压比热容的推算,用一些液体的p-v-T实验数据拟合了理论中所用LJ势能函数的势能参数,并提出一个通用关联式。本文方法具有通用性,在编制的计算程序中只需输入物质的临界温度、临界比容、偏心因子等就能算出相应的比热容,工程应用十分方便。  相似文献   

13.
李爱云  张浩勤 《河南化工》2001,(12):25-26,29
经过水淬形成的固体硅酸钠在堆放过程中极易结块,经过分析研究认为,硅酸钠的干燥基本上属于非结合水分的表面干燥,实验测定了硅酸钠的干燥速率,并探讨了穿流风速,风温对干燥速率的影响,依据实验结果进行了工业放大,设计了穿流带式干燥机,设备干燥效果良好,解决了产品结块问题,有良好的推广价值。  相似文献   

14.
从硅酸钠的性质特征出发,简要论述了硅酸钠制造工艺方法及目前我国该行业的状况。  相似文献   

15.
The calculation of the limiting opalescence temperature is proposed based on a model describing the mechanism of the formation of internal stresses in glass in cooling. The notion of the range of increased mobility of structural elements is introduced, which is identified with the glass softening range.  相似文献   

16.
Sodium-ion motion in three sodium silicate glasses and a sodium aluminosilicate glass was investigated by the thermally stimulated polarization (TSPC) and depolarization (TSDC) current techniques. The two TSDC peaks found in the sodium silicate glasses were attributed to localized sodium-ion movement around a nonbridging oxygen ion, a type of dipolar orientational polarization, and to a longer-range sodium motion leading to interfacial polarization at the immiscible phase boundaries. The high-temperature background (HTB) current corresponded to the sodium motion for dc conductivity and diffusion. The commonly observed dc absorption current was found to be related to the two TSDC peaks.  相似文献   

17.
硅酸钠模数测定方法的探究   总被引:1,自引:0,他引:1  
苏小莉  左国强  蔡天聪 《广州化工》2011,39(1):110-111,131
详细阐述了硅酸钠中氧化钠和二氧化硅含量测定的理论依据,在分析和总结现阶段测定二氧化硅含量存在问题的基础上,提出了改进的方法。通过采用过饱和氟化钠溶液,酸度计监测滴定终点的实验准确测定了二氧化硅含量,进而提高了硅酸钠模数测定的准确性和重复性。  相似文献   

18.
Activity data were calculated using the previously reported results for the variation of oxygen ion activity with composition and the best available thermodynamic data for the heats of formation of sodium monoxide, carbon dioxide, and sodium carbonate. The results are discussed in the light of the data for other systems and recent concepts of the structure of melts.  相似文献   

19.
由水玻璃(黑山膨润土制得)制备非晶态的纳米二氧化硅粉末.考察了乙醇浓度,电解质用量对白炭黑粒度的影响;酸化温度及酸化终点pH值对白炭黑回收率及质地的影响.并利用X射线衍射仪,红外光谱仪,扫描电子显微镜,粒度仪等对产品进行表征.研究结果表明当水玻璃的酸化温度为15℃时,产品白度下降,且回收率较低;当酸化温度为60℃时,红外分析显示SiO2分子中Si-O键和-OH增多,结合XRD图谱分析,SiO2分子中含有结晶水,呈结晶状,从扫描电子显微镜中可观察到SiO2粒径很大且不均匀;当酸化温度为30℃时,产品粒径均匀,为非晶态.由此确定水玻璃制备白炭黑的最佳工艺条件为:乙醇浓度为3.4 mol/L,NaCl用量为0.5g,在30℃时用一定浓度的硫酸溶液中和至pH =8.5,烘干后得白炭黑.此时得到的白炭黑回收率高,粒径均匀,达到纳米级别.  相似文献   

20.
Adlin Rose  R.  Preethi Jain  B.  Ramya  D.  Nilaa  M. 《SILICON》2021,13(2):599-603
Silicon - Around the world, agile growth in urbanization and industrialization led to increase in generation of solid wastes. Most of the time these solid wastes are not disposed properly. It is...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号