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.     

PC机通过USB口与工业控制系统的通信实现

工业领域中PC机与工业控制系统的通信方式一般通过串行口实现,鉴于通用串行总线USB（Universal Serial Bus）的优越性,设计了基于USB总线的数据采集系统．该系统是由增强型P89C61X2单片机、CAN控制器SJA1000和USB2．0接口芯片ISP1581组成,工业控制网络为基于CAN总线的现场总线控制系统。阐述了PC机通过USB口与工业控制系统（CAN网络）通信的实现方法和设计细节。结果表明,通过PC机的USB口可以对CAN总线控制网络上的数据和信息进行实时采集和处理,     

Nd对锌电积用Pb-Ag合金阳极性能的影响

采用恒流极化、失重法和抗拉强度测试研究不同含量Nd的加入对锌电积用铅银合金阳极主要性能(稳定阳极电位、耐腐蚀性能及力学性能)的影响,并在此基础上采用循环伏安(CV)和计时电位(CP)等电化学手段对恒流极化条件下Nd的作用机理进行研究。结果表明:0.03%Nd(质量分数)加入可以将Pb-Ag合金的抗拉强度提高21.8%;锌电积条件下,铅阳极表面腐蚀膜主要成分为PbO2及PbSO4,Nd加入可以抑制PbSO4的形成,从而明显降低阳极腐蚀速率;由于Nd能降低析氧过电位,且对高阻抗PbSO4的生成具有抑制作用,使得Pb-Ag合金的阳极电位亦有一定程度的下降。Nd对锌电积阳极主要性能均有较大程度的改进作用,是很好的锌电积阳极改性剂,具有较好的工业应用前景。     

二步煅烧法制备高振实密度钛酸锂负极材料

以Li2CO3和纳米TiO2为原料,通过二步煅烧固相反应法制备Li4Ti5O12负极材料。研究前驱体球磨以及球磨时间对合成Li4Ti5O12样品振实密度和电化学性能的影响。借助XRD、SEM、振实密度仪和充放电测试仪、电化学综合测试仪表征Li4Ti5O12材料的物理性能和电化学性能。结果表明:球磨工艺能够提高Li4Ti5O12的纯度,并有效提高其振实密度和电化学性能;球磨时间为2 h时,所得材料的振实密度达1.70 g/cm3,0.1C首次放电比容量为174 mA.h/g,5C放电比容量达124.2 mA.h/g。