钼酸钠抑制GCr15钢点腐蚀机理的研究

根据实验结果,作者认为钼酸钠抑制GCr15钢在中性介质中点腐蚀不是由于钼酸钠的去极化作用,而可能是由于MoO_4~(2-)与Cl~-竞争吸附,使Mo在点蚀活性点上富集,从而减弱了Cl~-的侵蚀活性,并且生成含有Fe~(3+)和Mo~(6+)的比较复杂的钝化膜。 根据MoO_4~(2-)和Cl~-竞争吸附模型,导出了MoO_4~(2-)和Cl-临界浓度之间的对数关系logC_(Mo)O_4~(2-)=AlogCc-+B,这与实验得到的结果完全一致.     

Rapid synthesis and properties of color-tunable phosphors SrMoO_4:Eu~(3+),Tb~(3+)

Color-tunable phosphors Sr_(0.94)MoO_4 :xEu~(3+),(0.06-x)Tb~(3+) were synthesized rapidly by microwave radiation method with active carbon particle as microwave absorbent. The synthesized phosphors were investigated by X-ray powder diffraction(XRD) and fluorescence spectrophotometer. The effects of the ratio of Eu~(3+) and Tb~(3+) on the phase structure and luminescent properties of the phosphors were discussed. The results show that Eu~(3+),Tb~(3+)-doped samples can be well indexed to the pure tetragonal scheelitetype SrMoO_4, indicating that Eu~(3+) and Tb~(3+) are effectively doped into the SrMoO_4 host lattices. The as-synthesized SrO 94 MoO_4:xEu~(3+),(0.06-x)Tb~(3+) phosphors have two luminescent centers(Eu~(3+) and Tb~(3+)), which can show red and green emissions under ultraviolet light excitation, respectively. Doping concentration of Eu~(3+) and Tb~(3+) has great effect on the intensity of emission peaks and the chromaticity of the samples, and the full color between green and red light can be achieved by adjusting the relative concentration of Eu~(3+)and Tb~(3+).     

Selective extraction of zinc from sulfate leach solution of zinc ore

1　INTRODUCTIONSolventextractionwasregardedasahighlyeffi cienttechniqueofseparationandpurification .Ithasbeenwidelyappliedinmetalextractionandrecoveryduringhydrometallurgicalprocessandenvironmentalprotection[14 ] .Solventextractionhasbeencommer ciallyusedintheextractionofuranium ,rarenoblemetals ,copper ,cobaltandnickel,whichwastypical lypresentedbythetechniqueofleach solventextrac tion electrowinning .Presently ,thecopperproductionfromsolventextractionhasbeenaccountedformorethan 2 0 %oft…     

几种离子对硫化亚铁膜离子选择性的影响

使用除氧的FeCl2和Na2S溶液在纤维素膜上制备出了硫化亚铁膜,通过测量膜电位曲线的方法,研究了硫化亚铁膜的离子选择性和几种阴、阳离子以及咪唑啉缓蚀剂对膜的离子选择性的影响.结果表明,硫化亚铁膜是一种双极结构膜,靠近FeCl2溶液一侧为阳离子选择性,与Na2S溶液接触一侧为阴离子选择性.这种双极结构膜能够加速钢铁的阳极溶解进而导致严重的腐蚀.硫化亚铁膜吸附Ca2+、Mg2+、Ba2+等阳离子后,由双极膜变为阴离子选择性膜;而吸附MoO2-4、PO3-4以及咪唑啉缓蚀剂后则变为阳离子选择性膜,这种阳离子选择性膜对膜下金属有一定的保护作用.同时采用动电位扫描法测试了表面形成硫化亚铁膜的A3钢在含有不同离子的3%NaCl溶液中的极化曲线.  TQ0288     

新混合萃取剂体系的萃取动力学和胶团化作用SCIEI

本文研究了协同萃取体系(D_2EHPA-H_2RPA-Al^(3+))的胶团化作用和界面特性[H_2RPA为长碳链单烷基磷酸脂,D_2EHPA为二(2—乙基己基)磷酸],以及液—液界面动力学。结果发现,混合体系中H_2RPA具有较强烈的胶团化作用和较高的界面活性,随着[D_2EHPA]的增加,其胶团化倾向和界面活性随之下降,H_2RPA和D_2EHPA具有完全相反的界面吸附行为,证实了非胶束混合萃取体系的动力学控制机制为界面化学反应控制型,得到了反应速率方程式,非胶束体系为有应用前景的混合萃取剂体系。     

EXTRACTION KINEIICS,MICELLIZATION AND INTERFACIAL CHARACTERISTICS OF A NEW EXTRACTANT SYSTEM

The interfacial kinetics,micellization and interfacial characteristics of the synergetic extrac-tion system,D_2EHPA-H_2RPA-Al~(3+),have been studied.H_2RPA is a single long chain alkylphosphate.We have found that H_2RPA in the mixed extractant system strongly exhibits thecharacteristics of micellization and interfacial activity.As the concentration of D_2EHPA in-creases,the micellization and interracial activity of H_2RPA decrease.The interfacialadsorption behaviour of H_2RPA is opposite to that of D_2EHPA.It was proved that the kine-tics of non-micella mixed extraction system was controlled by the chemical reaction at inter-face,and the reaction rate equation was obtained.This non-micella mixed extraction systemis expected to be used in the future.     

金属离子对低铬铸铁腐蚀磨损的影响

采用三体腐蚀磨损试验方法,研究了低铬铸铁在含Cu2 、Fe3 和SO42-离子的介质中的腐蚀磨损特性,并对腐蚀磨损机理进行了分析.结果表明,随着介质中Fe3 和SO2-4离子浓度的增加,低铬铸铁的腐蚀磨损耐磨性降低,而随着Cu2 离子浓度的增加,则耐磨性表现出先降低后增加的趋势.低铬铸铁在Cu2 和SO2-4离子介质中的磨损机制以显微切削、犁沟和腐蚀剥落为主,在Fe3 离子介质中以腐蚀和显微切削、剥落为主,但在原始介质中,则以显微切削和犁沟为主,兼有少量剥落.因此,介质中的离子参与了低铬铸铁的磨损过程.     

Existing form of Mo(Ⅵ) in acidic sulfate solution

The existing form of molybdenum in acidic sulfate solution was studied by means of ion exchange,infrared(IR) spectra and X-ray photoelectron spectroscopy(XPS).The results indicate that the anionic molybdenum species are predominant in acidic sulfate solution,and Mo(VI) can combine with sulfate radical to form heteropoly acid anions[Mo_2O_5(SO_4)_2]~(2-) and[MoO_2(HSO_4)_4]~(2-).With the decrease in solution pH from 1.92 to 0.06,the existing form of Mo(VI) changes from Mo_7O_(21)(OH)_3~(3-) to[Mo_2O_5(SO_4)_2]~(2-) and then becomes[MoO_2(HSO_4)_4]~(2-),which results in the decrease in the resin adsorption capacity for molybdenum.     

La~(3+)掺杂Y_2O_3透明陶瓷制备及发光性能

以Y2O3为基质材料,掺杂不同含量的La3+,采用机械力化学法制备纳米粉,粉体压制后在真空度1×10-3Pa下烧结得到La3+掺杂Y2O3透明陶瓷。采用透射电子显微镜(TEM)观察粉体一次颗粒形貌,扫描电镜(SEM)观察样品表面形貌,HV-1000型维氏硬度计测定样品硬度和断裂韧性,阿基米德法测定烧结后试样的相对密度,自动记录分光光度计测定试样透过率。结果表明:制备的La3+∶Y2O透明陶瓷透光率可达80%,掺杂La3+可以显著降低La3+∶Y2O3透明陶瓷的烧结温度;随着La2O3添加量的提高,样品透光率逐渐提高,但La2O3添加量过大会造成点阵畸变严重;随着La2O3添加量的提高,样品相对密度、维氏硬度和断裂韧性均逐渐提高,最后趋于平稳;随着保温时间延长,样品透光率也逐渐增大,继续增大保温时间,透光率趋于平缓。结合样品的透光率、相对密度、维氏硬度和断裂韧性考虑可知La2O3适合掺杂量、烧结温度和保温时间分别为10at%、1550℃和3h。     

Separation of Indium and Iron from Dilute Sulphate Solutions with a Phosphorous Mixer Extractant

In the conventional process [l], indium couldbe seParated from some bi-valence metals whileimpurity Fe' tha was most difficult to be sepa-rated was co-extfacted. When the extraCtion ofIn3 from lowly acidic solotions with D2EHPAas eXtfactani was carried ollt, the organic phasewas easily emulsified. FUrthermore, sttippingwas carried out difficultly and a high concelltfa-tion of striPping agent was required. IInPurityFe3 co-extracted with In3 into the organic phasecould not be strtheed …     

新型硫脲螯合树脂对金(Ⅲ)吸附性能的研究

用静态法较系统地研究了新型硫脲树脂从酸性含金氯化溶液中吸附金及其解吸金的性能,结果表明,在实验条件下,新树脂在含有Au3+、Cu2+、Ni2+和Fe3+等离子的混合体系中,对Au3+有良好的吸附容量和选择性,并能定量地解吸树脂所吸附的Au3+。在适宜条件下,该树脂对金的吸附率和解吸率均达到98%以上。     

SOLVENT EXTRACTION OF LANTHANIDES IN AQUEOUS NITRITE MEDIA BY CYANEX 302

ＳＯＬＶＥＮＴＥＸＴＲＡＣＴＩＯＮＯＦＬＡＮＴＨＡＮＩＤＥＳＩＮＡＱＵＥＯＵＳＮＩＴＲＩＴＥＭＥＤＩＡＢＹＣＹＡＮＥＸ３０２￥ＹＵＡＮＭｅｎｇ;ＬＵＯＡｉｑｉｎｇ;ＷＡＮＧＣｈｕｎ;ＬＩＤｅｑｉａｎ（ＣｈａｎｇｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉ...     

Extraction of copper from bacterial leach solution using LIX98

1　ＩＮＴＲＯＤＵＣＴＩＯＮＳｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｆｏｌｌｏｗｅｄｂｙｅｌｅｃｔｒｏｗｉｎｎｉｎｇ(ＳＸ ＥＷ )ｈａｓｂｅｃｏｍｅａｋｅｙｐｒｏｃｅｓｓｉｎｔｈｅｌａｓｔｔｗｏｄｅｃａｄｅｓｆｏｒｒｅｃｏｖｅｒｙｏｆｃｏｐｐｅｒｆｒｏｍｔｈｅｂａ     

β-二酮与CYANEX923或LIX84I混合萃取剂从氨性体系中协同萃锌(英文)

研究β-二酮(HA)与CYANEX923或LIX84I的混合萃取剂在氨性溶液中的萃锌行为;系统讨论有机相萃取剂浓度、水相pH、总氨浓度、温度和阴离子等对萃取性能的影响,从锌萃合物及β-二酮萃取剂结构方面讨论2个混合萃取体系的协同萃取机理。结果表明,HA与CYANEX923混合比与LIX84I混合具有更加明显的协同效应;水相pH和总氨浓度的升高均使萃取性能降低,因为升高pH或氨浓度会促使锌氨配合物的生成,降低水相自由锌离子的浓度,但HA与CYANEX923混合体系在较高pH或总氨浓度下仍具有明显的萃取性能;不同阴离子对HA与CYANEX923混合萃取体系的性能没有明显影响,但在HA与LIX84I混合萃取体系和单独使用HA萃取过程中以(NH4)2SO4NH4NO3NH4Cl顺序降低。     

A strategy to achieve efficient green-emission dual-mode luminescence of Yb~(3+), Er~(3+) doped NaBiF_4

A series of hexagonal phase NaBiF_4: x Yb~(3+) ,y Er~(3+)were successfully synthesized by solvothermal method. The morphology, phase structure, up-conversion luminescence and down-conversion luminescence properties of Yb~(3+) and Er~(3+) doping concentration and the energy transfer mechanism were studied. It shows that the doping of Yb~(3+) and Er~(3+) does not cause the phase transition of NaBiF_4, but influences its morphology. In the NaBiF_4:Yb~(3+) , Er~(3+), Yb~(3+) can transfer energy with Er~(3+), enhancing up-conversion green emission. With Yb~(3+) doping concentration increasing, the up-conversion red-green ratio will increase while the down-conversion intensity of the green emission decreases and that of the red emission increases. Considering the potential application of Na BiF_4:x Yb~(3+) , y Er~(3+) phosphors in optical illumination, the thermal stability was carried out.     

碱热处理对TC4合金微弧氧化膜生物活性的影响

利用微弧氧化技术在Ti6Al4V合金表面制备含钙、磷的多孔TiO_2涂层(记为MAO),并对涂层进行碱热处理(记为MAONH).结果表明:MAONH膜层的相结构和MAO膜层的大有不同,它主要由TiO_2(金红石型和锐钛矿型)、钛酸钙相组成.钙和磷离子在MAONH膜层表面比在MAO膜层表面更容易沉积,其原因是钛酸钙在模拟体液浸泡时发生水解,生成大量的Ca~(2+)和OH~- 离子,Na~+和OH~-离子同模拟体液中的Ca~(2+)和PO_4~(3-)离子发生离子交换,导致磷灰石在MAONH膜层表面沉积.     

Kinetics of gadolinium extraction with D2EHPA and Cyanex301 using single drop column

The extraction kinetics of Gd(III) from the nitric acid medium using bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex301) and 2-ethylhexyl phosphoric acid (D2EHPA) in kerosene solution were measured by the single drop technique. The influences of hydrogen ion concentration, gadolinium ion concentration, extractant concentration, column height, and nozzle diameter on the extraction rate were investigated. The forward rate equations for the gadolinium extraction with D2EHPA and Cyanex301 were obtained. Based on the experimental results, the forward extraction rate constant was calculated. With the increase of D2EHPA or Cyanex301 concentration, the drop rising diameter and the value of interfacial tension decrease in the studied system, which shows that D2EHPA or Cyanex301 has interfacial activity as a kind of surfactant. Also, the droplet diameter and interfacial tension decrease with the increase of aqueous solution acidity. The experimental results show that the D2EHPA extractant provides faster extraction rate in comparison with Cyanex301 extractant, and it would be useful in industrial continuous extraction process.     

预分散溶剂萃取法处理Cr(Ⅲ)废水(英文)

以2-乙基己基膦酸单2-乙基己基酯(HEHPEHE)为萃取剂,以及与其它萃取剂形成酸加酸、酸加碱、酸加中性混合萃取剂,通过考察萃取剂对废液中的Cr3+萃取分配比的影响,筛选出萃取Cr3+的适宜萃取剂HEHPEHE;采用预分散溶剂萃取技术对含Cr3+废液进行分离研究,以煤油为稀释剂,HEHPEHE为萃取剂,十二烷基苯磺酸钠(SDBS)为水性表面活性剂,吐温20(Tween-20)为油性表面活性剂,制备胶质液体泡沫CLAs。同时,为了研究预分散溶剂萃取技术萃取Cr3+废液的效果,考察了废液中的Cr3+浓度、胶质气体泡沫CGAs体积、萃取剂浓度、相比、阳离子表面活性剂十六烷基三甲基溴化铵(HTAB)浓度、阴离子表面活性剂SDBS浓度、表面活性剂Tween20浓度以及Cr3+废液的pH值等影响因素对Cr3+的萃取率影响,得到了萃取Cr3+的适宜条件;并用实际的含Cr3+废液进行检验,结果表明,在获得的适宜工艺条件下,经过二级萃取后,废水可以直接排放,Cr3+的萃取率超过99.9%。     

Photocatalytic activity of perovskite SrTiO_3 catalysts doped with variable rare earth ions

In this work,15 types of rare earth(Re) ions,including Y~(3+),La~(3+),Ce~(3+),Pr~(3+),Nd~(3+),Sm~(3+),Eu~(3+),Gd~(3+),Tb~(3+),Dy~(3+),Ho~(3+),Er~(3+),Tm~(3+),Yb~(3+) and Lu~(3+)doped perovskite SrTiO_3 powders were synthesized by solgel method.The influence of Re ions doping on the crystal structure,morphology and optical property as well as the photocatalytic activity for the photodegradation of rhodamine B(RhB) was investigated in detail when the synthesized Re ions doped SrTiO_3 powders were served as catalysts.The presented results revealed that the crystal structure is invariable,whereas the morphology and the optical bandgap are variable for the resultant SrTiO_3 powders when different Re ions were incorporated into the SrTiO_3 lattice.The relatedness between the morphology,optical property and photocatalytic activity of the synthesized SrTiO_3 catalysts doped with variable Re ions were analyzed deeply,providing an insight into the influence factors on the photocatalytic activity of catalysts.     

汽车发动机冷却液中镁合金缓蚀剂的研究

采用XRD、电化学极化曲线、化学浸泡等实验方法，研究了腐蚀性水体系中单种无机盐、复配无机盐缓蚀剂对AZ91D镁合金的缓蚀作用，并用正交优化设计确定了Na2MoO4+Na2SiO3+KMnO4复配无机盐缓蚀剂的优化配方；研究了水-乙二醇（1：1）防冻液基础液体系中缓蚀剂对AZ91D镁合金的缓蚀作用.结果表明，在腐蚀性水中KMnO4、Na3PO4、Na2MoO4和NaF对AZ91D镁合金有一定的缓蚀作用，Na2B4O7不具有缓蚀作用，有可能加速其腐蚀；复配Na3PO4+KMnO4及Na2MoO4+Na2SiO3+KMnO4对AZ91D镁合金腐蚀有缓蚀作用，而Na3PO4+Na2B4O7会加速其腐蚀.在水-乙二醇体系中，Na2S对AZ91D镁合金腐蚀有较好的缓蚀作用；确定了2种适用于水-乙二醇中的有机-无机复合缓蚀剂配方，缓蚀效率分别为98.1％和94.3％.