直流分布供电系统稳定性的分析与仿真

研究供电系统稳定性优化问题,针对直流分布供电系统中单独设计的功率模块级联后引起整个系统不稳定。由于系统连接,造成系统稳定性下降。为解决上述问题,提出了一种通过测量直流分布供电系统的稳定余度来判断系统稳定性的方法。在分析传统的判定稳定性方法缺点的基础上,根据Middlebrook判据,提出了禁止区域的概念,并进一步简化,推导出测量稳定余度的方法来判断级联系统的稳定性,并在SABER环境下对BOOST供电系统功率因数校正电路的稳定性。实验结果表明,方法能较为简便的判断直流分布供电系统的稳定性,同时对于其它供电系统的稳定性分析均有较好的参考价值。     

文科《多媒体技术与应用》课程设置与教学研究

多媒体技术是以数字技术为基础的综合技术。本文结合文科学生的特点,探讨了《多媒体技术与应用》课程设置与教学。     

Pd/Mg(OH)2 Heterogeneous Nanocatalysts Synthesized by a Facile One-Pot Hydrothermal Method for CO Direct Esterification to Dimethyl Oxalate

Catalysis Letters - Pd-based heterogeneous nanocatalysts have wide application in chemical industry. However, the traditional synthesis process contains multi-steps such as impregnation, dry,...     

An Analytical Model Including Interface Traps and Temperature Effects in Negative Capacitance Double Gate Field Effect Transistor

Silicon - In this paper, an analytical model for negative capacitance double gate field effect transistor (NC-DG-FET) is proposed. This model includes interface traps and temperature effects, which...     

铸铁在700℃时氧化过程的观察

利用光学显微镜、电子探针以及扫描电镜研究了灰铁、球铁和蠕铁在７００℃时的氧化过程。结果表明：（１）灰铁的氧化主要沿石墨与基体的相界面进行，初生奥氏体枝晶对氧的侵入具有一定的阻碍作用；（２）球铁是沿晶界比先氧化来实现其间接氧化的；（３）蠕铁氧化的模式主要取决于蠕化率的高低。     

Effect of additives on formation of natural gas hydrate

The formation of natural gas hydrate (NGH) is studied in this work. Kinetics data of hydrate formation with no agitation were collected at various concentrations of the aqueous solutions with different additives such as alkylpolyglucside, sodium dodecyl benzene sulfonate and potassium oxalate monohydrate. Various kinds of additive increased the formation rates of NGH and its storage capacity and reduced the induction time of NGH formation. Moreover, the storage capacity, the induction time and the hydrate formation rate were influenced by the concentration of the aqueous solution.     

无芯胶管的研制、工艺现状和发展建议

20世纪60年代初,我国胶管领域自主开发创新研制了无芯胶管制造技术,并且形成定型技术,一直沿用至今,笔者参与、见证了该产品从试验到投产的全过程。本文对该产品的工艺进行了新旧对比,提出了今后发展的建议。     

国产脱砷剂及其应用

介绍了石油烃中砷的存在形式 ,石脑油中砷含量及对催化剂的危害 ,分析了脱砷机理 ,阐述了国产脱砷剂的类型、型号、特点 ,以及选用原则与工业应用情况。     

氯乙酸生产工艺的改进与探讨

介绍了影响氯乙酸质量、消耗的因素,探讨了对氯乙酸工艺的改进措施。