Extraction Behavior of Rare Earths with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 Using Solid-liquid Extraction Technique

The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib-rium extraction constants and pH_(1/2) values of solid-liquid extraction are higher than those of normalliquid-liquid extraction.The extraction efficiency tends to maximum when the ratio of phases is 1:1.When theextraction temperature is higher than the melting point of paraffin and the extraction time is over 10 min,theextraction efficiency keeps constant.Moreover,the relationship among separation factor,equilibrium extrac-tion constant,pH_(1/2) value and atomic number was obtained.The mechanism of solid-liquid extraction isanalogous to that of liquid-liquid extraction.     

Paraffin wax as a diluent for extraction and separation of trivalent gallium, indium, and thallium with 2,6-bis-(1′-phenyl-3′-methyl-5′- oxopyrazole-4′) pyridineacyl

A method is proposed for the extraction and separation of trivalent gallium, indium and thallium from their corre-sponding aqueous solutions at 65°C with 2, 6-bis-(l'-phenyl-3'-methyl-5'-oxopyrazole-4') pyridineacyl (H2PMBPPor H2A)using molten paraffin wax as a diluent. The values of pH 1/2 for extraction of gallium, indium and thallium are 2.62, 4.32 and4.93, respectively. Gallium can be extracted by H2PMBPP at a lower acid medium. The effect of solvent and the composi-tion of the extracted species are reported. And the thermodynamic data of the extraction are also obtained.     

Oxidation Behavior and Oxide Layers of Ti–50Al Intermetallics by Preoxidation in High-Pressure Oxygen

The oxidation resistance of Ti–50Al intermetallics is improved bypreoxidation for 1, 4, or 16 hours in high-pressure, pure oxygen(3.9 atm) at 900°C. Specimens preoxidized for 1 hr exhibit betteroxidation resistance than others. Prolonged preoxidation time candeteriorate the oxidation resistance and reduce the parabolic-lineartransition time during subsequent cyclic oxidation in 800°C air. Theoxide-mound occurrence is an important factor for evaluating theeffectiveness of the preoxidation treatment in oxygen. The formationmechanism of Z-phase (Ti₅Al₃O₂) in the Al-depleted layer beneath theflat oxide scale and that beneath the oxide mound are also proposed inthis study.     

Potentialities of Raman Imaging for the Analysis of Oxide Scales Formed on Zircaloy-4 and M5® in Air at High Temperature

Micro-Raman imaging was used to investigate oxide scales formed on Zircaloy-4 and M5^® alloys in air, in the 800–1,000 °C temperature range. To create the 2D spectral images, the data were processed by different ways. The results clearly show that a microscopic picture of the scales in terms of microstructure and internal stresses can be developed from Raman spectral maps at the micron scale. Data on the microstructure, crystallography, and composition, are presented. They confirm that the crystallographic phases observed for the Zircaloy-4 and M5^® alloys are different, since, for Zircaloy-4, we clearly observed additional Raman signatures which most probably track the presence of nitrogen in the layers well before the occurrence of the kinetic transition. In particular, they show the presence of cubic zirconia in the layers, and strongly suggest the presence of zirconium nitride and oxynitride. Results also suggest the presence of strong stress gradients in the oxide scales.     

Synthesis and electrochemical properties of nanocrystalline Li[Li1／3Ti5／3O4] by complex sol-gel method

1　INTRODUCTIONSpinelLi[Li1/3Ti5/3O4 ]isaveryattractiveelec trodematerialforitsexcellentcyclelifeandpromisingchargingrateinrechargeableenergystoragecells .Duringelectrochemicalreactionsconsistingofelectronandlithiumioninsertionintoorextractionfromit,itslatticeconstantchangesveryslightly ,soitiscon sidereda“zero strain”insertioncompound[13] .Thismaterialwassuccessfullyusedasanodecoupledwithhighpotentialcathodematerials (LiMn2 O4 ,LiCoO2oractivecarbonfiber)toprovideacellorhybridsu perc…     

Microstructure and corrosion behaviour of plain carbon steel–B4C composite produced by GTAW method in 3·5 wt-%NaCl solution

In this work, the corrosion behaviour of metal matrix composite plain carbon steel–B₄C was studied in 3·5 wt-%NaCl solution. The composite was locally produced as weld band on plain carbon steel by means of gas tungsten arc welding process and using nickel as wetting agent. Samples from weld band, heat affected zone and base regions were extracted precisely, and electrochemical techniques including open circuit potential, linear polarisation resistance, electrochemical impedance spectroscopy, potentiodynamic polarisation in combination with SEM-EDX surface analysis and microhardness were used for characterisation. The results showed that hardness value of made composite increased significantly to 642 HV10. However, the corrosion resistance of composite region during 7 days (168 h) of exposure to 3·5 wt-%NaCl solution was slightly reduced. This was attributed to the fact that B₄C particles play as cathode site for oxygen reduction; therefore, they increase the corrosion rate slightly.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Paraffin wax as a diluent for extraction and separation of trivalent gallium, indium, and thallium with 2,6-bis-(l''''-phenyl-3''''-methyl-5''''-oxopyrazole-4'''') pyridineacyl

A method is proposed for the extraction and separation of trivalent gallium, indium and thallium from their corresponding aqueous solutions at 65 ! with 2, 6-bis-(1'-phenyl-3'-methyl-5'-oxopyrazole-4') pyridineacyl (H2PMBPPor H2A) using molten paraffin wax as a diluent. The values of pH1/2for extraction of gallium, indium and thallium are 2.62,4.32 and 4.93, respectively. Gallium can be extracted by H2PMBPP at a lower acid medium. The effect of solvent and the composition of the extracted species are reported. And the thermodynamic data of the extraction are also obtained.     

Determination of CeO_2 , Dy_2O_3, CuO and PbO in Yttrium Oxide Reference Material by Isotope Dilution Spark Source Mass Spectrometry

This paper describes the quantitative determination of rare-earth elements cerium, dysprosium andnon-rare-earth element copper, lead and the homogeneity examination of these four elements in yttrium oxidereference material by isotope dilution spark source mass spectrometry (ID-SSMS). The sensitivity of the meth-od is l0~(-5)～10~(-7%). The precision is better than 6%. The accuracy is better than 5%. The interferences of thespectra and the optimum amount of the spike added to the sample are discussed. The choice of the conductingmaterial for the sample electrodes is studied.     

Induced Co-colouration and Induced Co-decolouration between Different Rare Earths in the System of 《Metal(Ⅱ)-Rare Earth(Ⅲ)-Chromophoric Reagent-Sensitizer》

In co-colouration systems of rare earth(Ⅲ) with a metal(Ⅱ), induced colouration and decolouration ef-fects between different rare earths have been discovered. A sensitive co-colouration system of 《Lead(Ⅱ)-RareEarth(Ⅲ)-Alizarin Violet-Sensitizer》 was chosen as a typical one to study; and neodymium, gadolinium andyttrium were used to represent light, middle and heavy rare earths respectively. Semiquantitative relationshipsfor the induced effects between yttrium and neodymium as well as between gadolinium and neodymium havebeen determined and discussed. In the presence of a sensitizer, these metal ions cannot always be coloured byalizarin violet when each of them is present alone, but a very sensitive co-colouration or co-decolouration mayoccur during their coexistence under certain conditions. If these metals exist as foreign ions in the photometricdetermination of another metal, serious unperceivable interference will possibly occur. Moreover, the condi-tions leading to induced co-colouration and co-decolouration are very complicated, so that close attention mustbe paid to this area in the photometric determination of certain metals.     

Synergistic Extraction of Lanthanides by 1-Nitroso-2-Naphthol and Trioctylphosphine Oxide in Paraffin Wax

1 ＩｎｔｒｏｄｕｃｔｉｏｎＡｓａｋｉｎｄｏｆｓｅｐａｒａｔｉｏｎｔｅｃｈｎｉｑｕｅ ,ｓｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｉｓｗｉｄｅｌｙａｐｐｌｉｅｄ .Ｍｏｒｅ ｏｖｅｒ ,ｉｎｓｙｎｅｒｇｉｓｔｉｃｓｙｓｔｅｍｔｈｅｅｘｔｒａｃｉｎｇｐｏｗｅｒｏｆｔｈｅｍｉｘｔｕｒｅｅｘｃｅｅｄｓｏｂｖｉｏｕｓｌｙｔｈｅｓｕｍｅｆｆｅｃｔｏｆｔｈｅｅｘｔｒａｃｔｉｎｇｐｏｗｅｒｓｏｆｉｔｓｃｏｍｐｏｎｅｎｔｓ .Ｔｈｅｅｎｈａｎｃｅｄｅｘｔｒａｃｔｉｏｎｈａｓｂｅｅｎｏｂｓｅｒｖｅｄｉｎｍａｎｙｍｅｔａｌｅｘｔｒａ…     

Solvent Extraction of Some Lanthanides with Trioctylphosphine Oxide in Molten Paraffin Wax

TOPO has been applied to tiranium separation[l]. Some fundamental investigations for uranium extraction have also been well done [2, 3].However little data have been reported for theextraction of lanthanides with TOPO. Ceccoine[4] reported the lanthanides extraction withTOPO in chloroform at 25 C. Other authors stUdied the synergistic extraction of lanthanides byusing TOPO as a neutral adducts [5].For the past decade, the method using themolten paraffin wax as a diluent for the lanthan…     

稀土离子和香兰素在H2SO4溶液中对冷轧钢的缓蚀协同效应

用失重法研究了四种稀土离子(La3+,Ce3+,Ce4+,Nd3+)和香兰素(4-羟基-3-甲氧基-苯甲醛)在1.0 mol/LH2SO4介质中对冷轧钢的缓蚀协同效应。结果表明,香兰素对冷轧钢有中等程度的缓蚀作用,缓蚀率随其浓度的增加而增大;四种稀土离子对冷轧钢的缓蚀作用均较差,最大缓蚀率仅为20%左右。香兰素和稀土Ce4+复配后对冷轧钢产生了明显的缓蚀协同效应,最大缓蚀率可达95%左右;而与La3+,Ce3+和Nd3+复配后均无缓蚀协同效应。     

Investigation on Behavior of Rare Earth Element Cerium in Aluminum-Lithium Alloys by Internal Friction Method

1 ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｕｍｉｎｉｕｍ ｌｉｔｈｉｕｍａｌｌｏｙｓａｒｅｂｅｉｎｇｄｅｖｅｌｏｐｅｄａｓａｄｖａｎｃｅｄｓｔｒｕｃｔｕｒａｌｍａｔｅｒｉａｌｓｆｏｒａｅｒｏｓｐａｃｅｔｅｃｈｎｏｌｏｇｙｏｗｉｎｇｔｏｔｈｅｉｒｌｏｗｄｅｎｓｉｔｙ ,ｈｉｇｈｓｔｒｅｎｇｔｈａｎｄｓｐｅｃｉｆｉｃｒｉｇｉｄｉｔｙｃｏｍｐａｒｅｄｗｉｔｈｃｏｎｖｅｎｔｉｏｎａｌａｌｕｍｉｎｕｍａｌ ｌｏｙｓ ,ｂｕｔｔｈｅｒｅｓｔｉｌｌｅｘｉｓｔｓｏｍｅｄｉｓａｄｖａｎ ｔａｇｅｓ ,ｓｕｃｈａｓｌｏｗｐｌａｓｔｉｃ…     

Studies on the structural and ionic transport properties at elevated temperatures of La1−xMnO3±δ synthesized by a wet chemical method

Structural transformation and ionic transport properties are investigated on wet-chemically synthesized La_1−xMnO₃ (x=0.0–0.18) compositions. Powders annealed in oxygen/air at 1000–1080 K exhibit cubic symmetry and transform to rhombohedral on annealing at 1173–1573 K in air/oxygen. Annealing above 1773 K in air or in argon/helium at 1473 K stabilized distorted rhombohedral or orthorhombic symmetry. Structural transformations are confirmed from XRD and TEM studies. The total conductivity of sintered disks, measured by four-probe technique, ranges from 5 S cm⁻¹ at 298 K to 105 S cm⁻¹ at 1273 K. The ionic conductivity measured by blocking electrode technique ranges from 1.0×10⁻⁶ S cm⁻¹ at 700 K to 2.0×10⁻³ S cm⁻¹ at 1273 K. The ionic transference number of these compositions ranges from 3.0×10⁻⁵ to 5.0×10⁻⁵ at 1273 K. The activation energy deduced from experimental data for ionic conduction and ionic migration is 1.03–1.10 and 0.80–1.00 eV, respectively. The activation energy of formation, association and migration of vacancies ranges from 1.07 to 1.44 eV.     

十二烷基二羟乙基氧化胺在0.5 mol·L~(-1) H_2SO_4中对A3钢的缓蚀性能

通过失重法、电化学方法和量子化学计算法研究了十二烷基二羟乙基氧化胺(OAE-12)在0.5mol·L~(-1)H_2SO_4中对A3钢的缓蚀性能和作用机理。结果表明,在0.5mol·L~(-1)H_2SO_4中OAE-12能同时抑制A3钢的阴、阳极反应,缓蚀性能显著,当OAE-12质量浓度仅为200mg·L-1时,失重试验所得缓蚀率可达93.59%,且失重法、动电位极化曲线法、电化学阻抗谱法测试结果具有一致性;通过量子化学计算结果可知,OAE-12缓蚀作用机理可能是源于其分子内的氮、氧与钢表面的铁的相互作用。     

Corrosion inhibition of copper in chloride media by 1,5-bis(4-dithiocarboxylate-1-dodecyl-5-hydroxy-3-methylpyrazolyl)pentane

The efficiency of 1,5-bis(4-dithiocarboxylate-1-dodecyl-5-hydroxy-3-methyl-pyrazolyl)pentane (BDTCPP) as copper corrosion inhibitor in 3.5% NaCl solutions was studied by electrochemical polarization methods (Tafel extrapolation and polarization resistance method), electrochemical impedance spectroscopy and immersion assays. Results obtained in this study reveal that BDTCPP is a good inhibitor and the potentiodynamic polarization studies clearly show that BDTCPP is a mixed-type inhibitor for copper in chloride solutions. It decreases the anodic reaction rate more strongly than the cathodic reaction rate and it renders the open circuit potential of copper more positive in 3.5% NaCl solutions. The UV analysis of the protective layer of BDTCPP after corrosion experiments shows that the inhibitor prevents copper corrosion by physisorption on the metal surface, followed by chemisorption of a protective Cu(II)-complex. This Cu(II) is generated by oxidation of the Cu(I) ion formed at the beginning of the corrosion process in the aerated solution of NaCl.