运用神经网络方法进行电网最小割集搜索的硬件实现研究

本文研究了神经网络搜索图最小割集的方法，提出了这一方法硬件实现的可行方案，并已完成了电网可靠性计算的实验研究。     

研华工控机在酒精蒸馏控制系统中的应用

本文描述了一个应用于酒精蒸馏生产过程、以研华工业控制计算机为核心的控制系统，并介绍了系统硬、软件的配置和设计思想．     

大齿轮齿形在机测量原理与技术

在机测量大齿轮齿形误差具有广阔的发展前景。本文分析了大齿轮齿形误差在机测量的关键问题，提出了运用齿条刃边测头与被测齿轮横截面进行啮合的测量方法，既能测量齿轮的端截面齿形误差，又使仪器结构紧凑。在分析影响大齿轮形在机测量的诸误差因素的基础上，得出了在仪器的制造及安装精度要求不很高的情况下仍能实现齿轮的高精度测量的可喜结论。     

Adsorption of oxytetracycline from aquaculture wastewater by modified carbon nanotubes: kinetics,isotherms and thermodynamics

Abstract

In the present study, lanthanum modified carbon nanotubes (La-CNTs) were prepared by the impregnation method and used as adsorbents to remove oxytetracycline (OTC) from aquaculture wastewater. La-CNTs were characterized by SEM, EDS, XRD, BET analysis. The effects of adsorbent dosage, concentration of OTC, adsorption time, pH and interfering ions on the adsorption of OTC by La-CNTs were investigated. The optimum adsorbent dosage, OTC concentration, adsorption equilibrium time and pH for OTC adsorption by La-CNTs are 0.03?g, 20?mg/L, 180?min and 7, respectively. The outcome of the kinetics studies showed a significant linear correlation between the experimental results and the quasi-second-order kinetics model. As an adsorption isotherm model, the Langmuir model showed a very good consistency with the adsorption of OTC by La-CNTs, as the maximum adsorption quantity reached 117.23?mg/g. Through the thermodynamic analysis showed that the adsorption of OTC by La-CNTs was an endothermic process of entropy increase, which occurs spontaneously. The predominant forces promoting this adsorption were van der Waals force, π-π electron donor-acceptor interaction, and electrostatic interaction.     

Economic analysis of two processes for biodiesel production

In this study, two continuous processes for biodiesel production, alkali catalyzed process and solid acid catalyzed process, are discussed with the help of Aspen Plus. By comparing some economic indicators, it can be found that solid acid catalysis could be a good choice for investors in the near future.     

论我国北煤南运建设CWF加工业和CWF管道的可行性

据我国专家预测,我国在2030年之前,煤炭仍将是主要能源,北煤南运和节煤减排仍是长期的任务。分析了第二代水煤浆燃料(CWF)的优点:流变性稳定,储存期长(两年);加工过程并不复杂;可管输,埋于地下安全不冻,不受恶劣气候影响,无爆炸危险,可沿铁路铺设,不占农田。CWF发电NOx排放量比煤粉发电低20%～30%,又无堆煤场及煤粉加工粉尘危害。建议十二五规划中引进该项技术,在山西、陕西、内蒙古自治区西部交界地区建设CWF生产基地、集输管网并沿北煤南运三大铁路运煤通道敷设3条529mm实验CWF管道。采用开式流程和滚动开发技术,边建设边投产运行,尽快产生经济效益,立竿见影缓解北煤南运紧张度,以保证运输安全。     

周期性隔震基础的优化设计与试验验证

周期性隔震基础是利用周期性结构的衰减域特性,将地震动与上部结构自振频率接近的频率范围内的能量衰减,从而控制上部结构响应的新型隔震装置。周期性基础的隔震性能受到多方面因素的影响,包括局域共振子的调谐频率比、质量比、阻尼比、基体的刚度、上部结构与基础的相互作用以及地震动的频谱特性等。目前尚未有研究综合考虑上述因素的影响并提出周期性基础的设计方法。提出以一组地震动作用下上部结构峰值响应衰减率的平均值为目标函数,对周期性基础进行优化的设计方法。计算结果表明,按照该优化方法得到的周期性基础对上部结构在选取的44条地震动作用下,峰值响应的平均衰减率达30%。参数敏感性分析表明,优化设计得到的周期性基础对于自身参数的变化具有良好的鲁棒性。最后利用缩尺振动台试验验证了优化设计得到的周期性基础的隔震性能,证明了优化方法的有效性和优化结果的正确性。     

Porous Ni2P nanoflower supported on nickel foam as an efficient three-dimensional electrode for urea electro-oxidation in alkaline medium

Porous Ni₂P nanoflower supported on nickel foam (Ni₂P@Ni foam) electrodes are synthesized via a simple hydrothermal growth strategy accompanied with further phosphating treatment. The prepared electrodes are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). Electro-catalytic performances towards urea electro-oxidation are tested by cyclic voltammetry (CV), chronoamperometry (CA) coupled with electrochemical impedance spectroscopy (EIS). By phosphating Ni(OH)₂ precursor, the final obtained Ni₂P@Ni foam electrode presents a porous Ni₂P nanoflower structure within abundant porosity, and so exposes a large amount of electro-catalytic active sites and electronic transmission channels to accelerate the interfacial reaction. Compared with Ni(OH)₂@Ni foam precursor, the Ni₂P@Ni foam catalyst exhibits more excellent electro-catalytic activity as well as lower onset oxidation potential. Remarkably, the Ni₂P@Ni foam catalyst reaches a peak current density of 750 mA cm^?2 with an onset oxidation potential of 0.24 V (vs. Ag/AgCl) accompanied by an excellent stability in 0.60 M urea with 5.00 M KOH solutions. Benefiting from the unique porous nanosheet structure, the as-synthesized Ni₂P@Ni foam catalyst performs a highly enhanced catalytic behavior for alkaline urea electro-oxidation, indicating that the material can be hopefully applied in direct urea fuel cells.