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The cryolite ratio of the commercial aluminum cell electrolyte was determined by measuring the conductivity of the aqueous leaching solution ofthe sintered specimen which was prepared by adding quantitative sodiumfluoride into quantitative electrolyte specimen and then sintering it at 700℃.At the same time, the influence of the content of Al_2O_3. CaF_2. MgF_2 andLiF in the electroyte on the conductivity of the aqueous leaching solutionof the sintered specimen was studied. Furthermore, the dependence of... The cryolite ratio of the commercial aluminum cell electrolyte was determined by measuring the conductivity of the aqueous leaching solution ofthe sintered specimen which was prepared by adding quantitative sodiumfluoride into quantitative electrolyte specimen and then sintering it at 700℃.At the same time, the influence of the content of Al_2O_3. CaF_2. MgF_2 andLiF in the electroyte on the conductivity of the aqueous leaching solutionof the sintered specimen was studied. Furthermore, the dependence of thetemperature coefficient of the conductivity of the aqueons leaching solutionon the excess AlF_3 content in electrolyte specimen was determined by regression analysis. At last, the formula to calculate the cryolite ratio of thealuminum electrolyte with was derived. Data resulting from the ‘conductivity-method’ were checked against the thermo--titrimetic method. The average difference was about 0.02 between them. The researeh shows, the improved‘conductivity--method’ can be well used in the measurement of the cryoliteratio of the commercial aluminum cell bath. 用添加定量的NaF于定量的工业铝电解槽电解质试样中,且在700℃进行烧结,然后测定烧结试样水浸液的电导率的方法来确定电解质的冰晶石分子比。同时研究了电解质中Al_2O_3、CaF_2、MgF_2和LiF含量对烧结试样水浸液电导率的影响。进一步利用回归分析确定了水浸液电导温度系数与电解质试样中剩余氟化铝含量的关系。最后推导了计算电解质冰晶石分子比的公式。实验所测定的数据,用热滴定法进行了校核,平均相差0.02。研究表明,经改进的电导法完全能够应用于测定工业铝电解质冰晶石分子比。 The photoelectrochemical properties of n-type semiconductor CdS_(1-x) Sex (X=0.05, 0.1, 0.15, 0.3, 0.5) liquid junction photoelectrochemical cell prepared bypowder sintering pressed electrodes are described in this paper. The cell is representedasCdS_(1-x) Se_x/1M Na_2S, 1MNaOH, 0.1M (or 1M) S/Pt. The electrodes were analysed by means of X-ray diffraction and the scanning elec-tron microscope. The optical to electrical energy conversion efficiencies (η) under dif-ferent light intensities and direct sunlight... The photoelectrochemical properties of n-type semiconductor CdS_(1-x) Sex (X=0.05, 0.1, 0.15, 0.3, 0.5) liquid junction photoelectrochemical cell prepared bypowder sintering pressed electrodes are described in this paper. The cell is representedasCdS_(1-x) Se_x/1M Na_2S, 1MNaOH, 0.1M (or 1M) S/Pt. The electrodes were analysed by means of X-ray diffraction and the scanning elec-tron microscope. The optical to electrical energy conversion efficiencies (η) under dif-ferent light intensities and direct sunlight irradiation were measured. The Conversionefficiencies obtained were about 3.2% for solar intensity of 43mw/cm~2, and 3.28%for light intensity of 75mw/cm~2. Besides, the influence of the etchants on the electrode be-havior was investigated. No photoanodic dissolution was found for the Cds_(0.085)Se_(0.15)electrode in an electrolyte consisting of 1.0M NaOH, 1.0MNa_2S, and 1.0MS within 7hrs. The current-voltage characteristics curves (Ⅰ-Ⅴ) and the anodic current-potentialcurves (Ⅰ-Ф) were recorded directly under solar irradiation. 本文报告了由粉末压块烧结制备的n型半导体CdS_(1-X)Se_X(x=0.05,0.10,0.15,0.3,0.5)液结电池的光电化学性能。电池形式为: CdS_(1-X)Se_X/1M NaOH,1M Na_2S,0.1M(或1M)S/Pt对电极进行了X射线衍射及扫描电镜的分析,测试了在不同光照强度以及太阳光照下的转换效率(η)。光照强度为75 mW·cm~(-2)叫,CdS_(0.1)Se_(0.3)电池的转换效率η为3.28%;太阳光强为43mW·cm~(-2)时,转换效率为3.20%。同时还考察了浸蚀剂对电极性能的影响。CdS_(0.85)Se_(0.15)电极采用1MS的电解液在7小时内没有发现光阳极分解。直接地记录了在太阳光照条件下电池的电流电压特性曲线(I-V)及阳极极化曲线(1-Φ)。 The sample was prepared by sintering coprecipitation mixtures,of com- position (X/2)Gd_2O_3+(1-x) BaO+6Fe_2O_3,at different temperature,The phase composition of sample and the phase transition during sintering pro- cess were studied by X-ray and magnetic analysis,The Gd content in sample were determined by thermoneutron transmission,The pure M structure was obtained bysintering at 1310℃ when x≤0.12,X structure (when x≤0.15) or W structure (when 0.4≤x≤0.6) was obtained by firing at 1400℃.M(?)ssbauer,... The sample was prepared by sintering coprecipitation mixtures,of com- position (X/2)Gd_2O_3+(1-x) BaO+6Fe_2O_3,at different temperature,The phase composition of sample and the phase transition during sintering pro- cess were studied by X-ray and magnetic analysis,The Gd content in sample were determined by thermoneutron transmission,The pure M structure was obtained bysintering at 1310℃ when x≤0.12,X structure (when x≤0.15) or W structure (when 0.4≤x≤0.6) was obtained by firing at 1400℃.M(?)ssbauer, magnetic and electric measurements were carried out,For X structure,the magnetocrystalline anisotropy constant increased with x at room temperature. The Curie temperature of the sample with Wstructure was found about 80℃ higher then reported data,The effect of Gd~(3+) on the magnetic properties and the resistivity,and the interaction between Gd~(3+) and Fe~(3+) in M-type phase,of composition Ba_(0.9)Gd_(0.1)Fe_(12)O_(19),were discussed. 采用草酸盐共沉淀工艺制备了组成为(χ/2)Gd_2O_3+(1-χ)BaO+6Fe_2O_3的草酸盐粉料,预烧、成型后在不同温度下进行烧结。用热中子透射法测定了样品中的含钆量。用 X 射线衍射物相分析和磁分析方法研究了烧结过程中生成物的相组成及其相变。当χ≤0.12时,在1310℃烧结得到纯 M 相。在1400℃烧结得到的样品中,当χ≤0.15时为 X 相;当0.4≤χ≤0.6时主要相为 W 相。测量了样品的磁性、电阻率和 M(?)ssbauer 谱。发现在 X 结构化合物中,室温下的磁晶各向异性常数随含钆量的增加而增加;W 相化合物的居里温度比文献报导的数据高80℃左右。讨论了在含钆的 M 型六角铁氧体中,Gd~(3+)对磁性和电阻率的影响,以及 Gd~(3+)和 Fe~(3+)间的交换作用。
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