氮气保护在PP熔体流动速率测试中的作用

通过比较在有、无氮气保护的情况下聚丙烯(PP)熔体质量流动速率和熔体体积流动速率测试值的不同,探讨了PP熔体流动速率测试过程中氮气保护的作用。无氮气情况下PP在高温发生热氧化降解,分子链断裂,熔体变稀,致使测得的熔体流动速率值偏大;使用氮气吹扫可有效保护试样,更准确地测定熔体流动速率。     

配电网线路开断后潮流的新算法

在配电网回路阻抗法潮流算法的基础上,提出了一种新的配电网线路开断后潮流算法:对应取零法.该算法通过对已有的基态潮流方程的矩阵经过适当的变形,得到所求的因子表,从而节约了大量计算机时.对一个35节点配电网实例计算与比较的结果证明了"对应取零法"的可行性和正确性.     

油门踏板预变形注射模设计

介绍了汽车油门踏板的结构特点,通过模流分析计算出变形量,将3D数据按变形量进行反变形设计,达到注射成型后塑件的设计尺寸。     

中间轧制冷却工艺(IRQ)在炉卷生产线上的应用

介绍了安钢炉卷轧机生产线开发、应用IRQ控轧工艺替代传统控轧生产工艺的工艺流程及实施效果.     

The residual zonal flow in tokamak plasmas with a poloidal electric field

In a tokamak plasma with auxiliary heating by cyclotron waves, a poloidal electric field will be produced, and as a consequence influence the residual zonal flow(RZF) level. The poloidal electric field can also be induced through biasing electrodes at the edge region of tokamaks.Numerical evaluation for a large aspect ratio circular cross section tokamak for the electron cyclotron wave heating indicates that the RZF level decreases significantly when the poloidal electric field increases. Qualitatively, the ion cyclotron wave heating is able to increase the RZF level. It is difficult to apply the calculation to the real cyclotron wave heating experiments since we need to know factors such as the plasma profiles, the exact power deposition and the cross section geometry, etc. It is possible to use the cyclotron wave heating to control the zonal flow and then to control the turbulence level in tokamak experiments.     

Mucoadhesive Electrospun Nanofiber-Based Hybrid System with Controlled and Unidirectional Release of Desmopressin

The sublingual mucosa is an attractive route for drug delivery, although challenged by a continuous flow of saliva that leads to a loss of drug by swallowing. It is of great benefit that drugs absorbed across the sublingual mucosa avoid exposure to the harsh environment of the gastro-intestinal lumen; this is especially beneficial for drugs of low physicochemical stability such as therapeutic peptides. In this study, a two-layered hybrid drug delivery system was developed for the sublingual delivery of the therapeutic peptide desmopressin. It consisted of peptide-loaded mucoadhesive electrospun chitosan/polyethylene oxide-based nanofibers (mean diameter of 183 ± 20 nm) and a saliva-repelling backing film to promote unidirectional release towards the mucosa. Desmopressin was released from the nanofiber-based hybrid system (approximately 80% of the loaded peptide was released within 45 min) in a unidirectional manner in vitro. Importantly, the nanofiber–film hybrid system protected the peptide from wash-out, as demonstrated in an ex vivo flow retention model with porcine sublingual mucosal tissue. Approximately 90% of the loaded desmopressin was retained at the surface of the ex vivo porcine sublingual mucosa after 15 min of exposure to flow rates representing salivary flow.     

承钢炼铁3#风机计算机监控系统

介绍了“全可控涡”风机计算机监控系统的控制原理、系统组成及其功能,采用的新产品、新技术以及在承钢炼铁3#风机的应用情况。利用计算机监控系统进行风机监测;用DELPHI6作为开发平台,后台数据库采用InterBase7系统;首次采用阿牛巴流量计取代流量孔板,对风机出口流量进行检测;阐述了防喘振自动控制、轴振动和轴位移监测等几个风机运行关键问题。实际运行结果表明,该系统具有操作简便、控制精确、安全可靠等优点,提高了风机出风效率,降低了维护工作量和维护成本,具有较高的性价比。     

Synthesis and Biological Evaluation of Small Molecules as Potential Anticancer Multitarget Agents

Twenty-six triazole-based derivatives were designed for targeting both PD-L1 (programmed death receptor ligand 1) and VEGFR-2 (vascular endothelial growth factor receptor 2). These compounds were synthetized and biologically evaluated as multitarget inhibitors of VEGFR-2, PD-L1 and c-Myc proteins. The antiproliferative activity of these molecules on several tumor cell lines (HT-29, A-549, and MCF-7) and on the non-tumor cell line HEK-293 was determined. The effects on the abovementioned biological targets were evaluated for some selected compounds. Compound 23, bearing a p-chlorophenyl group, showed better results than sorafenib in regard to the downregulation of VEGFR-2 and a similar effect to BMS-8 on both PD-L1 and c-Myc proteins. The antiangiogenic and antivascular activities of chloro derivatives were also established by endothelial microtube formation assay on Matrigel^®.     

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...     

基于潮流跟踪的最小负荷削减费用计算

电网可靠性的经济性价值日益受到人们的重视,如何对其进行定量计算具有重要的现实意义.该文建立了体现电网可靠性经济价值的负荷削减费用模型,模型中综合考虑了节点负荷用户类型的分类和缺电损失评价率随停电时间的变化情况.在潮流跟踪法的基础上,提出了衡量负荷削减对缓解系统过负荷支路程度的经济性指标,并利用该指标对模型进行求解.算例结果验证了该方法的有效性和实用性.