Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium?

The extraction of Nd3 and Sm3 , including the extraction and stripping capability as well as the separation effect of Nd3 or Sm3 , from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd3 and Sm3 in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm3 or Nd3 . The chemical compositions of the extracted complex were determined as Nd·(HA2)2·HL2 and Sm·(HA2)2·HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.     

Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-（2-ethylhexyl） phosphoric acid from sulfuric acid medium

The extraction of Nd^3＋ and Sm^3＋, including the extraction and stripping capability as well as the separation effect of Nd^3＋ or Sm^3＋, from a sulfuric acid medium, by mixtures of di-（2-ethylhexyl） phosphoric acid （HDEHP, H2A2（0）） and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester （HEH/EHP, H2L2（0）） were studied. The distribution ratios and synergistic coefficients of Nd^3＋ and Sm^3＋ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3＋ or Nd^3＋. The chemical compositions of the extracted complex were determined as Nd.（HA2）2-HL2 and Sm.（HA2）2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.     

TRANSFER OF Ti AND Si BETWEEN SLAGS AND MOLTEN Cu UNDER CONSTANT OXYGEN POTENTIAL

An experimental study has been made of the mass transfer of Ti and Si between slags and mol-ten Cu under constant oxygen potential at 1500℃.Apparent mass transfer coefficients of Tiand Si in molten Cu have been obtained.     

高孔密度的泡沫铜对石蜡储热性能的研究

基于石蜡和高孔密度的泡沫铜制备了复合相变储热材料,设计并搭建了一套可视化储热实验装置,分析了高孔密度下泡沫铜的填充率对石蜡储热性能的影响.实验结果表明,当泡沫铜填充率从0％增至2.15％时,复合相变储热材料的融化时间从992 s缩短至872 s,缩短了11.69％,温度梯度从23.23 K减至7.77 K,降低了66....     

层燃炉中的“微爆燃”现象及其与炉拱的关系：炉拱理论的新进展

根据层燃炉冒正压的程度与燃煤挥发分含量有很大关系这一点,判定炉膛空间内未燃可燃气的“微爆燃”是一种未被发现的导致冒正压的原因。通过分析和验证“微爆燃”的机理及其与炉拱几何特性的关系,提出了消除微爆的各种方法。     

MgH2反应器储氢反应速度特性

为了探究镁基固态储氢反应器储氢反应速度的影响因素,建立了反应器三维数学模型.通过与文献中实验数据的对比验证了所建立模型的有效性.采用数值方法研究了导热油入口温度、供氢压力和环形导热油的油层厚度对储氢反应速度的影响.模拟结果表明,镁基固态储氢反应器存在最佳反应温度,过高或者过低的导热油入口温度都会降低储氢反应速度.导热油...     

基于可射击概率约束的防空作战火力优化分配

针对防空作战火力优化分配中未考虑可射击概率影响防空作战效能的问题,提出一种基于可射击概率约束的火力分配模型.该模型综合考虑可射击概率、空袭强度、火力单元转火时间等多种因素,能够在保证满足可射击概率和联合毁伤概率阈值前提下,优先使用反应快的火力单元拦截飞临时间短的目标,并尽量减少火力资源消耗,为防空系统提供持续作战能力....     

三叶片直线翼垂直轴风力机非定常流场速度分析

垂直轴风力机在回转过程中,叶片尾流的相互干涉和叶片攻角变化,使垂直轴风力机周围流场异常复杂。为探明直线翼垂直轴风力机在二维流场中速度分布及风力机叶片迎风角度变化关系,在风洞试验中采用激光多普勒测速仪(Laser Doppler velocimetry,LDV)技术,对所设计的三叶片直线翼垂直轴风力机流场风速进行试验研究,获得了该风力机叶片周围流场的速度分布情况。在建立直线翼垂直轴风力机在不同转速下叶片迎风角度变化的数学模型基础上,应用仿真软件对被测风力机流场进行分析计算。通过数学模型得知,来流风速夹角随回转角的变化情况可用正弦函数近似表示, 并且随着叶尖速比的增大逐渐减小。风洞试验和CFD结果表明,风力机在回转过程中,叶片前缘场域有乱流生成,并且该域风速值偏大;而在叶片旋转内部以及下流区域内会形成一个宽大的低速区域,并且伴随叶尖速比的增加,低速区域具有扩大趋势。     

基于流形学习和支持向量机的太赫兹谱分类

太赫兹时域光谱技术是一门新兴光谱检测技术,广泛应用于安检及反恐、生物医学和食品质量检测等方面。太赫兹谱的分类识别技术是太赫兹光谱检测技术的一个重要环节。由于受到噪声的影响,太赫兹谱可能在高维空间中成复杂的非线性分布,传统的分类方法难以取得理想的分类效果。流形学习和支持向量机都是当前机器学习领域的研究热点,都采取了核方法来解决非线性问题,正因为两者之间有很多共通之处,将这两种方法充分结合提出了一种称之为ISOMAP-SVM的新算法。这种新算法拥有比传统的支持向量机算法更快的训练速度和更好的分类效果。实验结果表明利用新算法可以实现对不同种类药品的识别,为太赫兹光谱技术用于药品的检测和识别提供了一种新的有效方法。     

不同岩石声发射时频特性实验研究

通过对变粒岩、花岗岩、石灰岩、粉砂岩等四种岩石进行室内单轴加载声发射试验,获取岩石破裂全过程的应力-应变曲线、声发射参数及声发射信号。根据岩石破裂过程,从时、频域对声发射信号进行分析,着重对比了不同岩石的力学性质、声发射信号频域特征。研究结果表明:采用声发射率、能率可以很好地描述岩石破裂损伤的整个阶段;随着加载的进行,根据岩体变形及破裂程度的不同,不同岩石破裂阶段的声发射信号的频带范围也在不断发生变化。结合声发射时间序列参数特征和频谱特性,可得出岩石破裂时的损伤特性,为现场岩体的稳定性监测提供技术支持。