Dependence of Generator Parameters on Pulsed Power Ice Breaking

In this research, an investigation on breaking of ice using a pulsed power generator for navigation of an icebreaker in an ice‐covered ocean is described. In these experiments, a pulsed arc discharge was formed using a Marx generator. In order to investigate the dependence of the input energy required for ice‐breaking on the circuit parameters of the generator, the capacitance of the generator was varied. The input energy for ice‐breaking was calculated from the waveforms of the electric power. It was found that the input energy for ice‐breaking decreased as the peak power increased with a decrease in the capacitance of the generator. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(2): 1–9, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22317     

A verification of the thermal stress analysis,including the furan sand mold,used to predict the thermal stress in castings

The restraint exerted on a casting by a furan sand mold on the casting and the contraction of the casting during cooling was dynamically and simultaneously measured using a device that we developed. The measurements were compared during cooling with thermal stress analyses. The thermal stress analyses were based on the representative mechanical models for the furan sand mold, i.e., the elastic and elasto-plastic models used in previous studies. The comparison demonstrated that the elasto-plastic model simulates the restraint force more accurately than the elastic model. In the thermal stress analysis, it was important to describe the development of inelastic deformation and the fracture of the sand mold. However, the simulated restraint force was still twice as large as the measured force even in the elasto-plastic model. This error is most likely attributable to using the temperature-independent mechanical properties of the furan sand mold and the mechanical model of the casting alloy, which neglected the viscoplasticity at high temperature in the thermal stress analysis.     

Effects of monomer and ether structure on metal-free living cationic polymerization of various vinyl ethers using hydrogen chloride with ether

A highly effective initiating system has been achieved for living cationic polymerization of vinyl ethers consisting of HCl alone without Lewis acid. This system is a facile metal-free living cationic polymerization using no HCl/Lewis acid but the already adopted complex HCl·Et₂O. In this study, we investigated the effects of a monomer and ether structure on the polymerization behavior. The monomers are classified into three kinds of monomers: alkyl vinyl ether, vinyl ether with electron-donating groups in the pendant, and vinyl ether with bulky group next to the electron-donating substituent in the pendant. The HCl·Et₂O systems were applicable for the polymerizations of all vinyl ethers used. However the structure around electron-donating groups in the pendant of monomer affected the polymerizations rate and induction period. The initiation reactions can be successfully achieved using ether effectively dissociating HCl, especially symmetrical ether.     

几种燃油炉的喷燃器喷嘴性能分析

通过对几种燃油炉的喷嘴性能的分析 ,合理地选择燃烧器的喷嘴结构 ,提高热效率 ,达到节约能源的目的。     

粘接技术在选矿设备维修中的应用

本文主要介绍粘接技术在选矿设备维修上的应用和在使用中应注意的一些问题 ,以及使用的效果     

PD characteristics and mechanisms in artificial air-filled voids atroom and liquid nitrogen temperatures

In this study, partial discharge (PD) characteristics in artificial air-filled voids at room and liquid nitrogen temperatures were investigated experimentally. It was found that minimum PD inception voltage at liquid nitrogen temperature (77 K) decreased with decrease in ambient temperature due to condensation of oxygen in the void. By observation of PD current pulses and light images, it was found that there were three modes of discharge: streamer, Townsend and glow like discharges in PD at room and liquid nitrogen temperatures. Especially the mode at liquid nitrogen temperature changes markedly with the stress time     

Plasma surface treatment of polymers with inductivity-coupled RF plasmas driven by low-inductance antenna units

Plasma surface treatment of polymers has been carried out with argon/oxygen mixture plasmas driven by multiple low-inductance antenna units. Kinetic energy distribution of argon ions from the argon/oxygen mixture plasmas onto polymers showed considerable suppression of ion energies sufficiently less than 10 eV. Polyethyleneterephthalate (PET) films were exposed to argon/oxygen mixture plasma for 1-5 min on a water-cooled substrate holder. The etching depth of PET surface increased with increasing plasma-exposure time and the etching rate was 118 nm/min. Surface roughness of PET surface (root-mean-square value) increased from 0.5 nm to 2.7 nm with increasing plasma-exposure time from 0 min (original sample) to 5 min. Hard X-ray photoelectron spectroscopy (HXPES) was carried out for analysis of chemical bonding states of the PET surface. The HXPES analyses exhibited nano-surface modification of the PET surface without suffering degradation of molecular structures beneath.     

工业锅炉除尘系统改造实践

锅炉除尘系统改造后 ,处理后的烟尘及二氧化硫均可达标排放 ,实践表明 ,改造后的除尘系统操作简单 ,运行可靠 ,管理简便 ,对锅炉使用没有任何影响 ,该技术在蒸发量 4t/h以下的锅炉除尘系统改造 ,有推广价值     

粗精矿预先分级产品分别处理的新工艺探讨

在不降低铜及伴生元素回收率的前提下提高铜精矿品位 ,是江铜面临的攻关课题 ,根据德兴铜矿选矿多年的生产实践及试验研究 ,提出采用一段粗精矿预先分级溢流、沉砂分别选别的新工艺及其它工艺措施 ,达到提高精矿品位和伴生元素回收率的目的