Carbonaceous mesophase spherule/activated carbon composite as anode materials for super lithium ion capacitors

A series of carbonaceous mesophase spherule/activated carbon composites were prepared as anode materials for super lithium ion capacitors using carbonaceous mesophase spherules as the core materials and pitch as the active carbon shell precursor.The structures of the composites were examined by scanning electron microscopy and X-ray diffractometry.The electrochemical performance was investigated in electric double layer capacitor and half-cell.The results show that,the composite exhibits good performance in...     

Electrical conductivity of (Na_3AlF_6-40%K_3AlF_6)-AlF_3-Al_2O_3 melts

The effects of contents of AlF3 and Al2O3,and temperature on electrical conductivity of (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 were studied by continuously varying cell constant (CVCC) technique.The results show that the conductivities of melts increase with the increase of temperature,but by different extents.Every increasing 10 ℃ results in an increase of 1.85×10-2,1.86×10-2,1.89×10-2 and 2.20×10-2 S/cm in conductivity for the (Na3AlF6-40%K3AlF6)-AlF3 melts containing 0%,20%,24%,and 30% AlF3,respectively.An increase of every 10 ℃ in temperature results an increase about 1.89×10-2,1.94×10-2,1.95×10-2,1.99×10-2 and 2.10×10-2 S/cm for (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts containing 0%,1%,2%,3% and 4% A12O3,respectively.The activation energy of conductance was calculated based on Arrhenius equation.Every increasing 1% of AlF3 results in a decrease of 0.019 and 0.020 S/cm in conductivity for (Na3AlF6-40%K3AlF6)-AIF3 melts at 900 and 1 000 ℃,respectively.Every increase of 1% Al2O3 results in a decrease of 0.07 S/cm in conductivity for (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts.The activation energy of conductance increases with the increase in content of AlF3 and Al2O3.     

Fabrication and anodic polarization behavior of lead-based porous anodes in zinc electrowinning

A new type of lead-based porous anode in zinc electrowinning was prepared by negative pressure infiltration. The anodic polarization potential and corrosion rate were studied and compared with those of traditional fiat anodes （Pb-0.8%Ag） used in industry. The anode corrosion rate was determined by anode actual current density and microstructure. The results show that the anodic oxygen evolution potential decreases first and then increases with the decrease of pore diameter. The anodic potential decreases to the lowest value of 1.729 V at the pore diameter of 1.25-1.60 mm. The porous anode can decrease its actual current density and thus decrease the anodic corrosion rate. When the pore diameter is 1.60-2.00 mm, the anodic relative corrosion rate reaches the lowest value of 52.1%.     

Na3A1F6-K3A1F6-A1F3熔体的电导率研究

通过连续改变电导池常数法（CVCC）,用自制的电导率测试装置研究KCl溶液与熔融KCl的电导率。实验证明连续改变电导池常数法能满足于一般的科学实验要求,自制的电导率测试装跫能满足常温实验和高温实验的电导率测试要求。通过此装置测定了钾冰晶石在（Na3AlF6＋K3AlF6）熔体中的含量为40％,AlF3在（Na3AlF6＋K3AlF6＋AlF3）混合熔体中的含量分别为0、20％、24％和30％的电导率,实验还讨论了AlF3含量对电导率的影响。     

工艺条件对铝电解NiFe2O4基惰性阳极热应力的影响

近年来惰性阳极已成为铝电解工业中的研究热点.以有限元软件ANSYS为开发平台,建立了单个惰性阳极实际工作条件下的有限元模型,以降低热应力,优化热应力分布为目标,研究了工艺条件包括电解质温度、电流强度、极距、阳极浸入电解质深度、环境温度、阳极与环境的换热系数等参数对惰性阳极热应力分布的影响.结果表明,在实际的工作条件下,阳极与电解质相接触的界面附近存在的轴向拉应力,是阳极开裂的主要原因.电解质温度和阳极浸入电解质深度是影响阳极热应力的两个最主要因素.温度升高、阳极浸入电解质深度增加都会使阳极的热应力分布变差.当电解温度由750℃上升到970℃时,第1主应力最大值和最小值绝对值分别上升了29.7%和29.6%,阳极浸入电解质深度由0.01 m变化至0.10 m时,第一主应力最大值和最小值绝对值分别上升了52.1%和65%.其他参数对阳极热应力分布影响很小.     

Prediction of Al（OH）3 fluidized roasting temperature based on wavelet neural network

The recycle fluidization roasting in alumina production was studied and a temperature forecast model was established based on wavelet neural network that had a momentum item and an adjustable learning rate. By analyzing the roasting process, coal gas flux, aluminium hydroxide feeding and oxygen content were ascertained as the main parameters for the forecast model. The order and delay time of each parameter in the model were deduced by F test method. With 400 groups of sample data （sampled with the period of 1.5 min） for its training, a wavelet neural network model was acquired that had a structure of {7^-21^-1}, i.e., seven nodes in the input layer, twenty-one nodes in the hidden layer and one node in the output layer. Testing on the prediction accuracy of the model shows that as the absolute error ±5.0 ℃ is adopted, the single-step prediction accuracy can achieve 90% and within 6 steps the multi-step forecast result of model for temperature is receivable.     

用于铝电解质动态测温的一种新算法

动态温度估计方法是解决铝电解过程温度在线检测的有效途径之一.本文提出了一种基于热电偶响应曲线时间常数的动态温度估计方法.实验表明,该方法具有可靠的收敛性和满意的测量精度.     

预焙铝电解槽智能模糊控制系统监控软件

用BorlandC＋＋3．1开发了集控制和槽况诊断于一体的铝电解槽智能模糊控制系统监控软件。软件具有监控功能丰富、人机界面友好、结构模块化、可扩充性强等特点。     

冶金过程人工神经网络建模及其参数优化策略

鉴于人工神经（ANN）网络在处理复杂系统方面卓越的能力,采用人工神经网络来处理冶金过程的系统建模问题,分析并建立了人工神经网络建模的框架及应用方法。在用网络模型仿真实际系统的基础上,详细论述了基于网络模型的3种系统参数优化策略。将已建立的模型应用于冶金实际生产,结果表明,预测结果与实际生产数值相当吻合。