变厚度透镜注射压缩成型的三维数值模拟

基于有限元法、Arbitrary Lagrangian-Eulerian有限元网格变形法理论及White-Metzner粘弹性本构方程,采用Moldex软件进行了变厚度光学透镜成型的三维仿真分析。模拟表明,压缩阶段的挤压流存在显著三维流动特征,较常规注射,注射压缩能有效地降低注射压力、剪切率与流动残余应力及因此造成的翘曲和光程差。减小压缩速度使压缩阶段浇口压力升高较小、熔体剪切作用减弱;增大压缩距离,可以降低注射压力,减弱剪切作用。实际上这些变量在厚度和距离浇口不同位置的分布不同。     

Metallic Graphene Nanoribbons

Isolated graphene nanoribbons(GNRs)usually have energy gaps,which scale with their widths,owing to the lateral quantum confinement effect of GNRs.The absence of metallic GNRs limits their applications in device interconnects or being one-dimensional physics platform to research amazing properties based on metallicity.A recent study published in Science provided a novel method to produce metallic GNRs by inserting a symmetric superlattice into other semiconductive GNRs.This finding will broader the applications of GNRs both in nanoelectronics and fundamental science.     

基于免疫聚类的RBF神经网络在中医舌诊诊断中的应用

研究基于人工免疫聚类的RBF(Radial-Basis Function)神经网络应用于中医舌诊诊断,构建一个中医舌诊智能诊断的神经网络模型,旨在提高模型的诊断能力和收敛速度.对输入样本集进行数据归一化处理,采用改进的基于免疫聚类的RBF算法进行学习、训练.以肝病病证诊断进行仿真,结果表明:该中医舌诊智能诊断系统具有诊断能力强、收敛速度快,泛化能力强等特点.因此,基于人工免疫聚类的RBF神经网络应用于中医舌诊诊断的研究是可行的,有效的.     

Insight into crystal growth and upconversion luminescence property of tetragonal Ba3Sc2F12 nanocrystals

Sc-based nanomaterials have attracted consid-erable attention due to their unique optical properties dif-ferent from those of Ln/Y-based nanomaterials.However,s...     

中空海胆状结构的碳包覆Fe2O3用作锂离子电池的高性能负极材料

Fe2O3由于成本低廉,储量丰富和理论比容量高(1007 mA hg^-1)等特点,在锂离子电池负极材料的应用中极具发展前景.然而一些问题仍然存在,如:充放电过程中比容量的迅速衰减,不可逆的体积膨胀以及较短的循环寿命等.这些问题严重制约了Fe2O3在锂离子电池中的实际应用.为了突破这些局限,本文以金属-有机骨架(MOF...     

Dried Blood Spots as Matrix for Evaluation of Valproate Levels and the Immediate and Delayed Metabolomic Changes Induced by Single Valproate Dose Treatment

The immediate and delayed metabolic changes in rats treated with valproate (VPA), a drug used for the treatment of epilepsy, were profiled. An established approach using dried blood spots (DBS) as sample matrices for gas chromatography/mass spectrometry-based metabolomics profiling was modified using double solvents in the extraction of analytes. With the modified method, some of the previously undetectable metabolites were recovered and subtle differences in the metabolic changes upon exposure to a single dose of VPA between males and female rats were identified. In male rats, changes in 2-hydroxybutyric acid, pipecolic acid, tetratriacontane and stearic acid were found between the control and treatment groups at various time points from 2.5 h up to 24 h. In contrast, such differences were not observed in female rats, which could be caused by the vast inter-individual variations in metabolite levels within the female group. Based on the measured DBS drug concentrations, clearance and apparent volume of distribution of VPA were estimated and the values were found to be comparable to those estimated previously from full blood drug concentrations. The current study indicated that DBS is a powerful tool to monitor drug levels and metabolic changes in response to drug treatment.     

侧链多阳离子型氟化聚芴醚阴离子交换膜及其全钒液流电池性能

阳离子基团的分布对阴离子交换膜的微观相态和阴离子传导率有显著的影响.为开发全钒液流电池用高性能阴离子交换膜,本文通过向含有二甲胺基团的氟化聚芴醚前驱体接枝含阳离子烷基链的方式,合成了具有相似离子交换容量的一系列侧链多阳离子型氟化聚芴醚.实验结果表明,多阳离子侧链的引入能促进微观相分离的形成并提升阴离子传导率.同时,侧链...     

Flexibility analysis and design of heat exchanger network for syngas-to-methanol process

The heat exchanger network (HEN) in a syngas-to-methanol process was designed and optimized based on pinch technology under stable operating conditions to balan...     

PCC在双转子连续混炼机控制系统中的应用

采用先进的PCC控制系统实现了对双转子连续混炼机的有效控制。介绍了该系统的整体方案,简述了该控制系统的特点,重点阐述了在设备运行中对混炼机、喂料机、单螺杆挤出机及切粒机等主要部件的连锁控制及对相关回路的PID控制。该系统具有友好的人机界面、操作简便、运行可靠等特点。