碱及等离子体处理对木棉纤维力学性能和吸水倍率的影响

研究了碱及等离子体处理对木棉纤维力学性能和吸水倍率的影响.结果表明:经碱处理后木棉纤维的力学性能得到了提高,纤维断裂强力提高了0.5~4 cN,断裂伸长率提高了18%~40%,吸水倍率提高了1.5倍;在板间距为3 mm的真空条件下用等离子体处理20 s后,木棉纤维的吸水倍率提高了2倍.     

化学吸收法测定多级离心雾化旋转填料床有效相界面积及体积传质系数

对多级离心雾化旋转填料床的有效相界表面积及体积传质系数,用化学吸收法做了实验测量。实验结果表明：多级离心雾化旋转填料床不仅具有超低气阻,而且可产生良好的喷雾扩展相界面积的作用,体积传质系数比传统填料塔提高一个数量级,接近气液逆流型旋转填料床。多级离心雾化旋转填料床开拓了新的气液传热传质途径。     

Preparation and properties of crystallizable Glass/Al<Subscript>2</Subscript>O<Subscript>3</Subscript> composites for LTCC material

The investigated low temperature Co fired ceramics(LTCC) composite of 60wt% CaO-Al2O3-B2O3-SiO2 glass and 40wt% α-Al2O3 as a filler is a non-reactive system, which is a critical part of the low temperature Co fired ceramics process. Through a study on densification process, the phase transformation and microstructure can be revealed. Its composites typically consist of CaO-Al2O3-B2O3-SiO2 glass and α-Al2O3 powders of average particle size (D50=3.49 mm). The sintering behavior, phase evaluation, sintered morphology, and microwave dielectric properties were investigated. In the fire range of 800 to 900 ℃, the composites were crystallized after completion of densification. It is found that the composites start to densify at 825 ℃, simultaneously, the dielectric constant (εr) reaches its maximum. With increasing heat-treatment temperatures, due to the loose microstructure of the material, tanδ increases slightly. The last of the sintered samples were identified as partly Anorthite at 850 ℃. At that temperature it has εr of 7.9 and tanδ less than 1×10-3, and can be used as a promising LTCC material.     

氧化铝/莫来石复合陶瓷的耐磨性

利用SiC和Al2O3纳米粉末在空气中通过反应烧结法制备了氧化铝陶瓷和氧化铝/0.96～8.7 2vol.%莫来石复合陶瓷。通过磨粒磨损试验测定了样品的耐磨性,观察了样品的磨损表面,测量了磨损表面的剥落面积比率。磨损率可以用磨损表面的剥落面积比率定量表示。相对于氧化铝陶瓷,氧化铝/莫来石复合陶瓷的耐磨性有很大提高,主要是由于减小了剥落面积比率。     

Oxidative coupling of methane in Ba0.5Sr0.5Co0.8Fe0.2O3−δ tubular membrane reactors

A dense membrane tube made of Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ (BSCF) was prepared by plastic extrusion from BSCF oxide synthesized by the complexing EDTA-citrate method. The membrane tube was used in a catalytic membrane reactor for oxidative coupling of methane (OCM) to C₂ without an additional catalyst. At high methane concentration (93%), about 62% C₂ selectivity was obtained, which is higher than that achieved in a conventional reactor using the BSCF as a catalyst. The dependence of the OCM reaction on temperature and methane concentration indicates that the C₂ selectivity in the BSCF membrane reactor is limited by high ion recombination rates. If an active OCM catalyst (La-Sr/CaO) was packed in the membrane tube, C₂ selectivity and CH₄ conversion increased compared to the blank run. The highest C₂ yield in the BSCF membrane reactor in presence of the La-Sr/CaO catalyst was about 15%, similar to that in a packed-bed reactor with the same catalyst under the same conditions. However, the ratio of C₂H₄/C₂H₆ in the membrane reactor was much higher than that in the packed-bed reactor, which is an advantage of the membrane reactor.     

精馏过程的新逐板计算法 (Ⅳ)多元精馏过程的设计型计算

对于精馏过程的模拟计算,大都已有严格算法适用于操作型计算.操作型方法虽可用于设计型计算,但增长计算时间.本文则提出用于直接设计型计算的新逐板法.设计型新逐板法选择比值为迭代变量.对于理想系统和与之相近系统,比值是指塔上部各板上各重组分分流量之比和塔下部各板上各轻组分分流量之比.对于萃取精馏系统,比值是指各板上各被分离组分的浓度之比.与操作型的新逐板法”相比,强回路不再存在,迭代回路全部由弱回路构成,因此具有更快的收敛速度.由于这是逐板计算法,故各股进料和侧线出料的最优位置可以方便地确定,而不必应用最优化判据或作最优化计算.     

武器装备军地一体化维修保障体系探讨

建立有效合理的武器装备军地一体化维修保障体系,充分调动军方和地方的维修保障资源,加强维修保障网络的信息沟通,协同完成武器装备的维修保障任务,可以提高武器装备系统战备完好性和任务成功性,并尽可能地降低对维修保障资源的要求,减少全寿命周期费用。提出了一种武器装备军地一体化维修保障体系,并分析了典型任务及分工,简要论述了战时与重大任务的维修保障体系。     

5G无线网络智能规划技术的探索与实践

研究并应用了多制式多网络的站址协同分析、5G站址智能寻优、弱覆盖栅格聚类识别、高精度3D规划仿真呈现等技术手段,将工具与生产流程有机结合,实现流程自动化,减少不必要的人工参与,提升整体规划效率,实现对5G网络资源的快速精准投放。最后,提供后续研究方向,为5G无线网智能化平台的进一步研究提供参考。     

Electrochemical behavior of K<Subscript>4</Subscript>Fe(CN)<Subscript>6</Subscript> in [bmim]PF<Subscript>6</Subscript>/TX-100/H<Subscript>2</Subscript>O based microemulsions

The electrochemical behavior of potassium ferrocyanide [K₄Fe(CN)₆] at Pt/ionic liquid (IL) microemulsion interfaces was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). H₂O/TX-100/bmimPF₆ was used to prepare three IL microemulsions: water in 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF₆) (W/IL), bicontinuous (WIL) and bmimPF₆ in water (IL/W). The results show that the IL microemulsion systems have relatively narrower potential windows compared with the pure IL system. The redox potential gap is about 100 mV in the pure water and the three IL microemulsions. The redox potentials of K₄Fe(CN)₆/K₃Fe(CN)₆ and the redox peak currents decrease in the order pure water, IL/W, WIL, W/IL. Furthermore, the peak currents increase linearly with the square root of the scan rate, while the diffusion coefficient increased in the order W/IL, WIL, IL/W. The Nyquist plots obtained in the WIL and IL/W systems show capacitive resistance arcs at high frequencies and 45° straight lines at low frequencies, implying that the electrochemical reactions are controlled by charge transfer and diffusion steps. For the W/IL system there is only a 45° straight line in the Nyquist plot, indicating that diffusion is the controlling step at all frequencies.     

SCTφ4.5 m磁力脱水槽工业试验

SCTφ4.5 m磁力脱水槽采用多层环型磁系，磁场分布合理，更有利于磁性矿物的磁团聚，从而提高对磁性矿物的回收能力。同时这种磁系还可以根据实际情况调整磁环层数，满足大型化设计的需要。在鞍钢集团矿业公司大孤山选矿厂的工业试验结果表明：SCTφ4.5 m磁力脱水槽的干矿处理量是现场生产用SCTφ3 m常规磁力脱水槽的2.33倍；在相同的给矿条件下，SCTφ4.5 m磁力脱水槽的精矿品位、尾矿品位及磁性铁损失率等指标均优于φ3 m磁力脱水槽，且SCTφ4.5 m磁力脱水槽比φ3 m脱水槽更容易适应给矿条件的变化。因此，SCTφ4.5 m磁力脱水槽具有较好的推广价值