Excel在玻纤配合料计算中的应用

介绍了在玻璃纤维生产中,利用Excel中的规划求解工具进行玻纤配合料的计算步骤,以实例详细阐述了玻纤配合料的计算过程,说明如何保存和使用一个非常简单实用的Excel计算模型,从而提高生产过程中工程技术人员的工作效率和计算精度。经过验证,计算结果准确无误。     

Regulation of biohydrogen production by heat-shock pretreatment facilitates selective enrichment of Clostridium sp.

The effect of heat-shock treatment to selectively enrich acidogenic, H₂ producing consortia was investigated for inoculum preparation and to control the process operation. Long term operation (520 days) in suspended-batch mode bioreactors illustrated relative efficiency and feasibility of heat-shock treated consortia (15.78 mol/kg COD_R) in enhancing H₂ production (3.31 mol/kg COD_R) when compared to parent (control) consortia. On the contrary, substrate degradation was higher in the control operation (ξ_COD, 62.86%; substrate degradation rate (SDR), 1.34 kg COD_R/m³-day) compared to heat-shock operation (ξ_COD, 52.6%; SDR, 1.10 kg COD_R/m³-day). Heat-shock pretreatment has resulted in a marked fermentation pathway shift towards acetic-butyric acid type production. The microbial diversity illustrated dominance in the Clostridia class after applying heat-shock pretreatment. The redox catalytic currents and Tafel analysis strongly support the conclusion of an improved biocatalyst performance after pretreatment with regards to H₂ production.     

Cost optimization for series–parallel execution of a collection of intersecting operation sets

A collection of intersecting sets of operations is considered. These sets of operations are performed successively. The operations of each set are activated simultaneously. Operation durations can be modified. The cost of each operation decreases with the increase in operation duration. In contrast, the additional expenses for each set of operations are proportional to its time. The problem of selecting the durations of all operations that minimize the total cost under constraint on completion time for the whole collection of operation sets is studied. The mathematical model and method to solve this problem are presented. The proposed method is based on a combination of Lagrangian relaxation and dynamic programming. The results of numerical experiments that illustrate the performance of the proposed method are presented. This approach was used for optimization multi-spindle machines and machining lines, but the problem is common in engineering optimization and thus the techniques developed could be useful for other applications.     

Dynamic simulation,numerical control and analysis of a novel bottom flashing scheme in batch distillation

In this communication, the concept of bottom flashing under the mechanical heat pump system is introduced in the batch distillation columns. Proposing an operating strategy at transient state, a numerical control mechanism is formulated to simultaneously adjust the following variables aiming to ensure the optimal use of internal heat source: flow rate of reboiler liquid subjected to bottom flashing, operating pressure of throttling valve, compression ratio for pressure adjustment in the isentropic compressor and external heat input to the reboiler. The potential of this novel energy efficient batch distillation is numerically quantified in terms of the two performance indexes, namely energy savings and cost. Finally, a binary system is dynamically simulated to demonstrate the proposed configuration.     

基于DMOLPP的间歇过程在线故障检测

为了保持过程数据集的局部结构,确保数据投影后的投影向量正交,降低数据误差重构方面的难度,提出了一种基于动态多向正交局部保持投影(DMOLPP)进行间歇过程故障检测的方法。该方法将滑动窗口技术和正交局部保持投影(OLPP)相结合用于间歇过程在线检测。首先,将批次数据展开成二维数据,利用滑动窗口技术分别在时间片内运用OLPP算法提取能表征过程正常数据内在局部近邻结构的特征;然后,对于新来批次数据标准化处理后分别在相应窗口内投影,提取特征向量;最后利用核密度估计(KDE)确定控制限进行过程检测。通过仿真结果表明,运用DMOLPP算法检测到故障发生的时刻早于动态多向局部保持投影(DMLPP)、动态多向邻域保持嵌入(DMNPE)方法。与动态多向主元分析(DMPCA)相比,具有较低或者无误报时刻,验证了该方法的有效性。     

无铵助镀剂条件下氯化镍对锌层厚度及组织结构的影响

采用光学显微镜和扫描电镜对角钢在氯化镍含量不同的无铵助镀剂中助镀获得的镀层进行了镀层金属间化合物层形貌和镀层厚度的分析。结果表明,在一定范围内,随着氯化镍含量的增加,获得的镀层厚度不断减小,当氯化镍含量增加到6g/L时镀层厚度不再随氯化镍含量的增加而减薄,氯化镍含量增加到6~8g/L时镀层最薄,氯化镍含量为4~8g/L时能获得厚度适中的镀层;氯化镍含量对镀锌层的形貌有影响,随着氯化镍含量的增加金属间化合物层中的ζ金属间化合物层减薄,晶粒尺寸减小。Γ和δ金属间化合物变化不明显。     

间歇蒸煮技术的发展

介绍了上世纪80年代以来发展起来的三种间歇蒸煮技术,即RDH法、Sunds-Celleco法和超级间歇蒸煮法,并说明了它们比传统的间歇蒸煮技术优越的原因。     

冷堆前处理的工艺与设备

根据笔者设计的冷堆练标工艺和设备条件，论述了冷堆练漂的工艺技术，设备要求、操作要点和实践效果。采用冷堆前处理工艺，可大幅度降低设备投资费用、能源消耗，且能减少定员，提高正品率和实物水平，适应小批量多品种生产，为短流程前处理开辟了一条高效，经济的新途径。