Optimization of sugar release from banana peel powder waste (BPPW) using box-behnken design (BBD): BPPW to biohydrogen conversion

Optimization of pre-treatment conditions has been achieved for total sugar release from banana peel powder waste (BPPW) feedstock modelled through a three-level Box-Behnken design (BBD) of the response surface methodology (RSM). A series of various runs were executed at varied acid (H₂SO₄) concentrations (0.05%–0.15% v/v), incubation periods (1 h–3 h) in water bath at 95 °C and alkali (NaOH) concentrations (0.05%–0.15% v/v) according to the Box-Behnken design (BBD). From RSM the significant values of incubation period, acid concentration and alkali concentration were obtained as 3 h, 0.095% v/v, and 0.05% v/v respectively. The maximum total sugar release was reported as 5243.62 μg/ml which was highly close to the predicted value (5010.07 μg/ml). The model P- value (0.001), R-sq (98.26%), (adj) R-sq (95.14%) and (pred) R-sq (79.56%) obtained through ANOVA justified the results. The mutual impact of alkali and incubation period had the highest effect on total sugar release from dried banana peel powder, followed by mutual impact of acid and incubation period based on ANOVA (Analysis of Variance) results.Under optimized conditions of pre-treatment six different substrate concentrations (1%, 3%, 5%, 7% and 9% w/v) of BPPW was hydrolyzed and used to obtain volumetric bio-hydrogen evolution. The highest cumulative volumetric bio hydrogen gas 43 ml H₂/30 ml media was achieved at 5% w/v of pretreated BPPW. The substrate concentration above 5% w/v resulted in lowered fermentation process owing to product and substrate inhibition.     

应用Minitab进行测量系统分析

测量系统分析是工程应用领域中分析测试数据是否可靠的方法之一。阐述了测量系统分析的基本概念、重复性和再现性的定义、测量系统分析的前提、数学模型、测量系统能力的评价准则,同时以电子枪旋转度测量系统为例阐述了利用Minitab进行测量系统分析的过程,并对Minitab生成的图形进行分析和阐述。     

基于Minitab的TFT-LCD产品标准化率影响因素分析及改进

利用Minitab软件,结合无辐射薄膜晶体管有源矩阵液晶显示器(TFT-LCD)行业特点,分析了产品标准化率的影响因素。从共用次数权衡系数K1和跨工厂共用修正系数K2两个维度完成了模型改进,并成功应用于实际数据分析中,证实改进模型的可行性,实现了预期效果。     

对位芳纶聚合物黏度对纤维断裂强度的影响分析

采用Minitab软件对千吨级对位芳纶生产中聚合物比浓对数黏度对纤维断裂强度的影响进行分析。首先,对聚合物比浓对数黏度和纤维断裂强度的测量系统进行验证,得出测量系统的变异影响都是在可接受的范围;然后采集生产现场数据对聚合物比浓对数黏度对纤维断裂强度和纺丝成纤率的影响进行分析,得出纤维断裂强度和纺丝成纤率随着聚合物比浓对数黏度的增大而增大,但当聚合物比浓对数黏度达到一定值后成纤率下降,并找出了聚合物比浓对数黏度较佳控制范围为6.3~7.0 d L/g。     

汽车用POM油泵支架法兰注塑工艺研究

通过Moldllow分析法兰成型填充特点,采用DOE方法设计注塑工艺参数,通过分析试验数据,研究注塑工艺参数对法兰质量的影响.结果表明,保压时间是聚甲醛(POM)油泵支架法兰注塑工艺中最重要的影响因素,对提高注塑工艺水平具有指导意义,同时可缩短产品的开发周期、降低后续的调机费用,为企业带来显著经济效益.     

基于Minitab DOE的铝丝楔焊键合工艺参数优化

为提高国产陶瓷外壳用于铝丝楔焊键合的可靠性和产品质量,利用Minitab统计软件对一种封装形式为CQFP84的国产陶瓷外壳用于铝丝楔焊键合的工艺参数进行试验设计,并对试验结果进行直观分析和方差分析。讨论过键合功率、键合压力、键合时间及超声功率缓慢上升时间(Ramp)对键合拉力的影响及其显著程度。试验研究表明第2段参数的键合压力、第2段参数的键合功率及第1段参数的Ramp对键合拉力值有显著影响,以键合拉力为参考指标,得到了较优的键合工艺参数,通过验证试验键合拉力相比工艺参数优化前有明显提高,分散度也有明显改善,达到了提高产品可靠性的目标。     

用Minitab进行测量系统分析

以滚动轴承制造现场使用的D0 12轴承检测仪的“GR&R”研究为例 ,介绍用Minitab进行测量系统分析的方法 ,并以分析数据为依据对测量仪器作相应的调整和改进     

Effect of various packaging materials on storage stability of refined,bleached, deodorized palm oil

Refined, bleached, deodorized palm oil (RBD palm oil) was packaged in lacquered metal cans (LMC), green glass bottles (GGB), amber glass bottles (AGB), clear glass bottles (CGB), clear plastic bottles (CPB) and sealed polyethylene film (POLET), and stored in direct sunlight (40 ± 1°C) or in darkness (27 ± 1°C). Measurements of free fatty acid (FFA), peroxide value and anisidine value, at 14-day intervals for a period of 98 days, were used to assess the stability of the oil towards hydrolytic and oxidative deterioration. Total oxidation values for packaged oils stored in direct sunlight showed that LMC gave the greatest protection against oxidative deterioration, followed by GGB and AGB. POLET offered the least protection to the oil against oxidative deterioration, while CPB and CGB proved superior to POLET but inferior to GGB and AGB. For storage in the dark, LMC, AGB and GGB gave the greatest protection to RBD palm oil against oxidative deterioration, with no significant statistical differences between them, while CPB, CGB and POLET followed in that order, with significant differences between their respective abilities to protect the oil against oxidative deterioration. Oils packaged in CPB gave the highest FFA levels (statistically significant). The investigations clearly indicated that LMC is superior to all other tested packaging materials in offering maximum protection to RBD palm oil against hydrolytic and oxidative deterioration. Amber and green glass bottles could serve as viable alternatives to LMC, while CGB and CPB could be tolerated as suitable packaging systems for RBD palm oil. However, the study also clearly showed that POLET is unsatisfactory for use as packaging material for RBD palm oil.     

基于对应分析的汽车细分市场购买因素研究

通过大规模的消费者问卷调查,运用Minitab软件,采用对应分析的统计方法,分析了不同类别的乘用车细分市场中消费者购买因素的差别。大规模的消费者调研能获得足够的样本对市场进行细分,而Minitab对应分析模块则突破了以往的频度统计和相关分析对数据挖掘的局限性,将细分市场和购买因素的对应关系直观地呈现在二维坐标图中。结果表明,随着乘用车类别由小型车向大型车的提升,消费者购买时考虑的因素从价格、省油和亲友推荐等车辆的外在属性,逐步过渡到考虑容易驾驶、外观、质量和舒适等车辆本身的属性,直至对车辆的性能、安全和品牌信誉等更高属性的追求。     

基于六西格玛管理法在降低焦比方面的分析

以六西格玛管理理念为基础,利用Minitab软件对2500m3高炉生产焦比进行过程能力分析,确定焦比过程能力不足,有很大的降低空间,并通过失效矩阵分析、相关分析和回归分析确定影响焦比的主要因素有煤比、富氧率和入炉矿石品位,并利用试验设计（DOE）确定当煤比为180kg/t、富氧率为2.9%、入炉品位为57.5%时,焦比达到最低值,以此为现场生产提供参考和指导。