含磷酸根离子和三价铁离子的溶液中镓的沉淀行为研究

研究了磷酸根离子对镓离子和三价铁离子沉淀过程的影响以及在含磷酸根离子的溶液中三价铁离子对镓离子沉淀过程的影响。实验结果表明磷酸根离子能促进镓离子和三价铁离子的沉淀,其沉淀率都随磷酸根离子浓度的增加而增加,直至磷酸根离子与待沉淀的金属离子摩尔比达到1∶1,进一步提高磷酸根离子浓度,镓离子和铁离子沉淀率几乎不变。在相同的磷酸根离子浓度和pH下,三价铁离子比镓离子容易沉淀。在含磷酸根的溶液中,三价铁离子对镓离子的沉淀过程具有促进作用,并且镓的沉淀率随Fe3+/Ga3+摩尔比的增加而增加,Fe3+/Ga3+摩尔比从0增加至5∶1时,镓完全沉淀所要求的pH从3.5降低到3.0。采用共沉淀法可以在较低的pH下比较完全地从溶液中回收镓。     

In-situ energy calibration of SSRF macromolecular crystallography beamline using powder diffraction

<正>For X-ray powder diffraction spectra collected by an area detector of MarCCD on macromolecular crystallography beamline of SSRF,an energy calibration method was developed using LaB_6(660a) powder diffraction for in-situ rapid energy calibration of the X-rays without changing the experimental conditions.The intensity of each diffraction ring was integrated,and the accurate peak positions were fitted by Pseudo-Voigt function model.The sample's interplanar spacing for XRD analysis and the calibrated energy were obtained by the PCPDFWIN code and by fitting all the energies with the least-square method.The exposure time and the sample-to-detector distance were found no effect on accuracy of the energy calibration,and the in-situ energy calibration could be done with an accuracy of better than 0.4‰in 7-18 keV.This method is applicable to other X-ray beamlines.     

Mathematical Simulation of Flow Field for Molten Steel in an 80–ton Single Snorkel Vacuum Refining Furnace

The three–dimensional flow field of molten steel in an 80–ton single snorkel vacuum refining furnace has been mathematically simulated to attain the optimal configuration and operation parameters, such as the bottom blowing Ar flow rate, the eccentric position of bottom blowing Ar port at ladle bottom, the single snorkel inner diameter, and the single snorkel immersion depth into molten steel. The mathematical simulation results show that a stable flow field of molten steel can be achieved in 70–second; meanwhile, the maximal circulation intensity of molten steel in the 80–ton single snorkel vacuum refining furnace can be found on a cross–section with y as 0 mm based on the middle of ladle bottom as circular point of the Cartesian space coordinate under the condition of injecting Ar gas on x coordinate considering the asymmetry of flow field for molten steel in the single snorkel vacuum refining furnace. The recommended parameters of the 80–ton single snorkel vacuum refining furnace with ideal circulation intensity as 970.1 kg/s are the bottom blowing Ar flow rate as 450–500 Nl/min, the eccentric position of bottom blowing Ar port as 250 mm, the single snorkel inner diameter as 1000 mm, and the single snorkel immersion depth as 500 mm.     

世界航空钛市场现状及发展趋势

介绍了美国、俄罗斯、欧洲及亚洲的航空钛市场现状,分析了民用客机、军用飞机及航空发动机对钛材的需求形势。目前,世界航空钛市场处于复苏阶段,波音与空客两大公司的订单开始大幅增加。世界航空钛市场中长期前景看好,用钛量将持续攀升。预计到2015年,世界航空用钛材交货量将达到12.5万t。     

谈黄金工业污染源及其治理现状

随着中国黄金工业的迅速发展,黄金生产过程中的工业污染物排放总童和种类也在增加和变化.为了确保黄金工业的可持续发展,黄金行业主管部门、黄金生产企业及科研单位,应及时掌握黄金工业污染源的产生及其治理情况和发展变化规律,并依据国家环境保护法律法规、技术政策和相关标准,及时提出主要污染源削减和治理的技术途径.文中通过对部分黄金...     

唐钢连铸坯热送热装实践

结合唐钢连铸坯热送热装工作实践，提出做好生产组织协调提高企业整体管理水平是热送热装工作的关键，多品种，批量生产是提高热送热装率的有利条件。     

当归药膳的配伍与制作探讨

当归是目前药膳餐厅中的常用中药材,具有补血活血的作用,对于平时保健也大有裨益,但其在餐饮行业中运用较混乱,没有相应的制作标准。本文从食物搭配、烹饪方法、选用合理的调味等方面,就如何合理有效地制作当归相关药膳进行了研究、探讨,为药膳的发展、推广提供参考。     

利用中子CT技术定量分析钛合金含氢量的理论研究

钛合金机械性能受氢含量的影响,由于中子与氢反应截面相对于钛合金基底要大得多,因此中子照相技术在钛合金氢含量定量分析中具有潜在应用价值。为将中子照相技术应用于钛合金含氢量定量分析中,提出了通过钛合金标准件与含氢样品的中子CT图像获取氢分布状况的方法;推导出计算钛合金含氢量的公式,并通过蒙特卡罗方法模拟了不同厚度、不同含氢量的钛合金来验证该公式的正确性。     

PEM系统中可控时钟电路设计的优化

介绍了为乳腺专用正电子发射断层扫描仪PEM(Positron Emission Mammography)电子学数据获取(Data Acquisition,DAQ)系统提供稳定、可靠、抗干扰的高精度同步时钟的电路,它采用了基于单片机和高精度时钟产生芯片的电路设计方法,可以得到多路可控时钟信号.设计中采用差分传输,大大降低...     

ADS次临界系统中子时空动力学计算与瞬态分析

加速器驱动次临界反应堆(ADS)中子时空动力学计算需要考虑外中子源和空间分布的影响,比临界系统中子动力学计算要复杂得多。本文将改进准静态(IQS)近似与蒙特卡罗(MC)方法相结合,对于带外源的ADS次临界系统中子时空动力学过程,形状函数、动力学参数由MCNPX程序计算得到,幅度函数与集总参数热工反馈模型进行耦合计算,并开发了IQS/MC计算程序可视化操作界面。针对CIADS靶堆耦合系统参考方案物理模型,对引入束流瞬变及无保护失流工况过程进行瞬态模拟计算分析,给出了堆芯相对功率、燃料温度及冷却剂出口温度随时间的变化曲线。同时,将中子注量率进行分群计算,得到了堆芯分能群的相对中子注量率网格分布随时间的变化,模拟结果与理论分析一致。