汽提气制冷天然气液烃回收新工艺

介绍一种新型汽提气制冷天然气液烃回收工艺,阐述了工艺流程及特点。采用Aspen Hysys2006软件对汽提气制冷天然气液烃回收工艺进行了模拟计算。通过对模拟结果的分析发现,在回收率相同的情况下,新型汽提气制冷天然气液烃回收工艺比现役工艺能耗降低了15%。对国内现役天然气液烃回收工艺的改进有一定参考价值。     

企业加强纪检监察工作的思考

纪检监察工作是企业党建工作的重要方面,是党的思想建设的主要内容。企业专业化重组的新形势下,对进一步做好纪检监察工作提出了新要求。文章就如何进一步加强和改进纪检监察工作、促进企业科学发展进行思考。     

Optimal disc cutters plane layout design of the full-face rock tunnel boring machine (tbm) based on a multi-objective genetic algorithm

Improving of the quality of the disc cutters’ plane layout design of the full-face rock tunnel boring machine (TBM) is the most effective way to improve the global performance of a TBM. The plane layout design of disc cutters contains multiple complex engineering technical requirements and belongs to a multi-objective optimization problem with multiple nonlinear constraints. Based on analysis of the technical requirements of the plane layout problem, an optimizing mathematical model was built. To obtain a set of design schemes for engineers to choose from, a multi-objective genetic algorithm (MOGA) was applied to carry out the optimization of the mathematical model. A constraint-domination principle was utilized to handle the constraints, and a nondominated sorting method was adopted to obtain Pareto solutions. Simulation results showed that the proposed method was efficient and accurate in obtaining the Pareto layout solutions.     

经管类"管理信息系统"课程教学改革探讨

"管理信息系统"是一门非常重要的基础性课程.随着课程建设的不断发展,在教学过程中会不可避免地暴露出一些问题.为此,本文在问卷调查的基础上,分析了经管类学生的学习现状,并透过学生的视角,总结了MIS教学过程中存在的问题,进而提出"四位一体"的教学改革模式,以期推动管理信息课程的建设.     

Electrochemical performance of Nd1.93Sr0.07CuO4 nanofiber as cathode material for SOFC

Nd_1.93Sr_0.07CuO₄ nanofibers are prepared by electrospinning technique followed by a simple thermal treatment. The morphology and phase evolution of as-obtained fibers are characterized by TG-DTA, XRD, FT-IR and SEM, respectively. Typical ceramic fiber diameter is 100–200 nm, with length exceeding tens of microns. Rapid heating the nanofiber cathode at 1000 °C for 15 min results in homogeneous porous microstructure and good contact with the CGO electrolyte. EIS analysis of the nanofiber electrode gives a polarization resistance of 0.26 Ω cm² at 700 °C in air, two times smaller than that from the powder cathode with the same composition. The excellent electrochemical performance can be attributed to the well constructed microstructure of the fiber cathode, which can promote surface oxygen diffusion or adsorption processes on the cathode.     

高功率脉冲磁控溅射沉积原理与工艺研究进展*

高功率脉冲磁控溅射技术是一种峰值功率超过平均功率2个量级、溅射靶材原子高度离化的脉冲溅射技术,作为一种新的离子化物理气相沉积技术,已成为国际研究的热点,有关高功率脉冲放电、等离子体特性、薄膜及其工艺等方面的研究进展十分迅速。文中从高功率脉冲磁控溅射的原理出发,介绍10多年来高功率脉冲电源的发展,从高功率脉冲放电等离子体特性与放电物理、等离子体模型,以及沉积速率和薄膜特性等方面综述技术的研究进展。     

微观相场法研究应变能对Ni68.2Al22.7V9.1合金中两相沉淀及原子占位的影响

采用微观相场方法,以 Ni68.2Al22.7V9.1 合金为例研究了应变能对两相沉淀及原子占位的影响。研究结果显示:沉淀过程中应变能明显使 L12沉淀相增加,对DO22相的沉淀有一定的抑制作用;由于 DO22相减少,V原子在L12相中各个位置的占位几率增大,而且应变能越大占位几率越高;应变能对Al原子在L12相中的α1位的占位几率影响不大,只有小幅度的降低,但明显降低了Al原子在α2位和β位的占位几率;各种情况下V原子在 L12相β位的占位几率始终高于α位。     

Effect of oxidation and heat treatment on the morphology and electronic structure of carbon-encapsulated iron carbide nanoparticles

Carbon-encapsulated iron carbide nanoparticles have been produced by co-carbonization of a mixture of an aromatic heavy oil and ferrocene at 450 °C under autogenous pressure. Transformations of the morphology and electronic structure of nanoparticles induced by air oxidation and subsequent heat treatment in a nitrogen atmosphere were examined using transmission electron microscopy, X-ray diffraction, near edge X-ray absorption fine structure spectroscopy, and X-ray emission spectroscopy. It was found that hollow nanoparticles, composed of iron oxides and oxidized carbon, were developed with thermal air oxidation of the initial product at 280 °C for 5 h. The mild oxidation of the product (250 °C for 3 h) followed by the carbonization at 500–550 °C yielded the hollow nanoparticles containing iron carbide/oxides and defective graphite-like carbon. The further annealing of nanoparticles at 1000 °C produced carbon nanocapsules with highly graphitized carbon walls and partially filled by spherical iron carbide nanoparticles.