熔接痕位置预测及优化技术研究进展

综述了熔接痕位置预测、优化和控制技术的研究进展,介绍了填充过程熔接痕形成的数学模型。对数值模拟技术、数值模拟技术结合数学规划理论、阀式浇注和大型注射成型制品多浇口进料顺序控制技术等3种技术的分析流程、预测方法和应用实例进行了详细介绍,其中基于数值模拟技术和数学规划理论结合的熔接痕位置确定新算法是行之有效的熔接痕位置优化技术,已成为当前研究热点。随着该技术的日趋成熟,应用范围将逐渐增大。而阀式浇注和大型注射成型制品多浇口进料顺序控制技术的实施可以成功避免注塑件熔接痕的出现,在大型零件生产中具有广阔的应用前景。     

Optimization strategies for separation of sulfadiazines using Box-Behnken design by liquid chromatography and capillary electrophoresis

Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for the separation of interested components. Box-Behnken factorial design was effectively applied for the separation optimization of eight structurally related sulfonamides using capillary zone electrophorosis and reverse high performance liquid chromatography. Optimum values for volume ratio of THF to H2O in eluent, column temperature and flow rate of eluent are found as 12 to 88, 35 ℃ and 1.0 mL/min, respectively. Box-Behnken modified optimization model is extended to separation by capillary electrophoresis （CE）. While using CE, a satisfactory separation is achieved with a minimum resolution larger than 1.0 for a separation time less than 10 min.     

工艺参数对ABS、PP注塑件翘曲变形影响的对比研究

运用Taguchi DOE技术研究了工艺参数对丙烯腈-丁二烯-苯乙烯共聚物(ABS)和聚丙烯(PP)两种材料注塑件翘曲变形的影响,并获得优化的工艺参数以使制品的翘曲变形量最小.以碱性蓄电池盖为例,利用L9(34)正交矩阵进行实验,并采用标准变量分析法(ANOVA)对工艺参数对制品翘曲变形的影响程度进行了对比研究,结果表明:对于两种材料的电池盖,在所选工艺参数中,保压压力和熔体温度对翘曲变形的影响程度最大,获得了最佳工艺参数组合,并预测出在优化工艺参数组合下的最小翘曲量,对注塑生产具有一定的指导意义.     

镀银件废品镀层的回收和利用

通过试验,找到了不合格镀银件镀层的回收方法,确定了银镀层的回收和利用工艺.     

伊凡思蓝修饰玻碳电极上邻、对苯二酚的电化学性质及同时测定

循环伏安法和差分脉冲伏安法研究了伊凡思蓝修饰玻碳电极上邻苯二酚(Catechol,CC)和对苯二酚(Hydroquinone,HQ)共存体系在0.1 mol/L磷酸缓冲溶液(PBS)中的电化学行为。实验结果表明,在pH=7的PBS中,扫描速率为100 mV/s,循环伏安法扫描电位在-0.1~0.5 V时,分离效果明显。差分脉冲伏安法测定了两种物质的混合溶液,线性范围均为1×10-6~50×10-6mol/L,检出限分别为0.32×10-6和0.18×10-6mol/L。     

成型工艺参数对MBS、PP注塑件收缩率的影响

运用Taguchi技术研究了成型工艺参数对甲基丙烯酸甲酯-丁二烯一苯乙烯共聚物(MBS)和聚丙烯(PP)注塑制品收缩率的影响,并获得优化的成型工艺参数以使制品的收缩率最小.以碱性蓄电池壳为例,利用L9(34)正交矩阵进行实验,研究对比了成型工艺参数对制品收缩率的影响程度.结果表明,所选成型工艺参数中冷却时间和注射时间对MBS制品的收缩率影响较大.熔体温度和冷却时间对PP制品的收缩率影响较大.     

钢带氨基磺酸盐镀镍工艺

通过电镀工艺对比,证实了氨基磺酸盐镀镍工艺可以实现大电流快速电镀。给出了镀液配方及合理的工艺参数。电镀中氨基磺酸镍含量越高,则分散能力越高、结晶更细致、内应力更小;但当含量大于600g/L时,电流效率减小。氨基磺酸镍含量应控制在350～500g/L范围内为宜。尝试了将氨基磺酸盐镀镍工艺应用于钢带镀镍生产,保证了生产的进度。     

共沉淀法合成磷酸铁锂的途径概述

共沉淀法合成LiFePO4材料的步骤简单,成本低且颗粒均匀,通过控制材料的形貌,粒径,可制备出高振实密度,高倍率性能良好的材料。随着对共沉淀法的深入研究,合成的途径也越来越多,文章介绍了不同LiFePO4材料的合成途径和各种途径的优缺点,并对共沉淀法包覆和掺杂改性的研究情况做了简单的介绍。     

聚邻甲氧基苯胺薄膜对pH的光学响应

在盐酸介质中,应用循环伏安法通过电聚合在氧化铟锡(ITO)透明导电玻璃上形成聚邻甲氧基苯胺薄膜.用紫外可见光谱方法测定了聚合物薄膜在不同pH下的特征吸收光谱,聚邻甲氧基苯胺薄膜的λmax在557～746nm之间,作出了相应的滴定曲线.结果表明,在pH为1～12范围内聚合物薄膜对pH的变化表现了极高的光学敏感性,其表观pKa约为6.4.应用聚邻甲氧基苯胺薄膜测定了不同pH的溶液,其测定结果与精密酸度计相比误差＜±4%.     

Fast preparation of photopolymerized monolithic columns for capillary electrochromatography

Photopolymerized sol-gel（PSG） columns were prepared using methacryloxypropyltrimethoxysilane as the monomer, toluene as the porogen and hydrochloric acid as the catalyst. Four different photoinitiators such as benzoin methyl ether, Irgacure 819, Irgacure 1700 and Irgacure 1800 were comparatively used in the reaction solution in the presence and absence of sodium dodecyl sulfate. The above eight solutions were respectively irradiated at 365 nm for 5 10 min in each capillary （75 μm inside diameter） to prepare the porous monolithic sol-gel column by a one-step, in situ, process. The chromatographic behavior of the eight PSG columns were comparatively studied, all of which exhibit reversed-phase character. Using these columns, several neutral compounds, namely thiourea, benzene, toluene, ethyl benzene, biphenyl and naphthalene can be separated from mixtures with a largest column efficiency of 74 470 plate/column for thiourea. Addition of sodium dodecyl sulfate in the polymerization process has a significant influence on the morphology and migration time.