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| 1 | 白云鄂博稀土、铌、钍在矿石中分布规律及伴生关系显示文摘利用电感耦合等离子原子发射光谱(ICP)对白云鄂博矿中稀土、铌、钍元素含量进行检测并分析这些元素在矿石中分布规律及伴生关系。分析显示,稀土、铌、钍元素呈类似于正态分布,但在高、低浓度显著偏离正态分布曲线;镧、铈、镨、钕具有很高的伴生关系,相关性均值为0.92;稀土与铌元素呈弱相关,相关系数为0.037;稀土与钍元素呈负相关,相关系数为-0.2。研究结果对稀土、铌、钍的富集分离具有重要的现实意义;低含量稀土可与高含量稀土如镧和铈一同富集分离;稀土元素的富集,使用适当的方法如X-射线拣选,可以不影响铌、钍元素的富集。 | 张铁柱 王建英 李保卫 刘明宝 张雪峰 | 2015 | 稀土2015，36，5： | 14 |
| 2 | Surface structure and catalytic performance of Sr-doped La_2NiAlO_6 double perovskite catalysts for methane combustion显示文摘A species of novel Sr-doped rare earth double perovskite catalysts(La_(2-x)Sr_xNiAlO_6,x=0,0.1) were prepared by the sol-gel method using citric acid as a complexing agent and calcined at 1100 ℃ for 3 h,then investigated for methane catalytic combustion.The as-prepared catalysts were characterized by X-ray diffraction patterns(XRD),H_2-temperature-programmed reduction(H_2-TPR),specific surface area(BET),magnetic property measurement technology(M-H),scanning electron microscopy(SEM),and X-ray photoelectron spectroscopy(XPS).Experimental results showed that La_(1.9)Sr_(0.1)NiAlO_6 catalyst exhibited significantly improved catalytic activity(T_(10)=378.7 ℃,T_(90)=602.9 ℃) compared with that of La_2NiAlO_6,whose T_(10) decreased by 74.4 ℃ and T_(90) decreased by66.8 ℃,respectively.The excellent catalytic activity of La_(1.9)Sr_(0.1)NiAlO_6 caused by Sr-doping could be explained by the larger number of adsorption oxygen on the catalyst surface,which could be proven by XPS analysis. | 胡瑞生 白雅琴 杜航宇 张慧敏 杜燕飞 张俊阁 周啟华 | 2015 | Journal of Rare Earths2015，33，12： | 7 |
| 3 | 白云鄂博矿脱磷选铁及部分回收稀土、铌的新工艺显示文摘为了直接利用白云鄂博原矿冶炼钢提供低P的铁精矿,并同时回收其他有价元素。针对含P 1.05%,含Nb 0.19%的原矿进行了反浮选-弱磁选试验,采用油酸钠为捕收剂,在碱性条件下去除大部分磷灰石和稀土矿物,再对反浮选尾矿经弱磁选得到了含P 0.046%品位为68%的低P铁精矿,Fe回收率达80%;从磁选尾矿可回收回收率44.06%品位0.65%的Nb矿。同时从反浮选产品回收相当原矿91.15%,品位12%的稀土矿物。因此本实验提供了一种获得低磷铁精矿,并部分回收稀土、Nb的新工艺。 | 吴旭 王建英 李保卫 张铁柱 王介良 | 2016 | 中国稀土学报2016，34，4： | 5 |
| 4 | Moderate concentration of citric acid for the formation of LaMn03 and LaCo03 nano-perovskites显示文摘 | | 2013 | Journal of Rare Earths2013，31，10： | 3 |
| 5 | Improving of photocatalytic activity of barium ferrate via bismuth and copper co-doping for degradation of paracetamol under visible light irradiation显示文摘Nanosized Ba_(1-x)Bi_(x)Fe_(1-x)Cu_(x)O_(3)(12–50 nm)with x values of 0,0.01,0.05,and 0.1 system was prepared using the Pechini method.Structural,morphological,surface and optical characterizations were performed for the prepared samples.Cubic phase was the predominant phase for the undoped BaFeO_(3)and Bi and Cu co-doped BaFeO_(3)samples.Minor phases of monoclinic Ba_(2)Fe_(2)O_(5),orthorhombic BaFe_(2)O_(4)and orthorhombic BaCO_(3)were identified for all the prepared samples.Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)sample has the lowest band gap(2.43 e V).98.1%paracetamol removal was achieved with 0.75 g/L of Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)at pH9 after 120 min.The paracetamol degradation follows the pseudo first-order kinetics.HO·is the main oxidative species responsible for the paracetamol degradation.Gas chromatography–mass spectrometry(GC–MS)analysis was performed at the end of the photocatalytic degradation experiment under optimum operating condition using Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)to explain the reaction mechanism and identify the intermediate by-products which is confirmed by ultraviolet/visible(UV/Vis)spectroscopy study at different reaction times. | Hussien Ahmed Abbas Rabab Ahmed Nasr Rose-Noelle Vannier Tarek Samir Jamil | 2022 | Journal of Environmental Sciences2022，34，2： | 2 |
| 6 | La_(0.8)Ce_(0.2)MnO_3/PG的制备及其催化燃烧甲苯性能显示文摘以盐酸改性之后的凹凸棒石(PG)为载体,La_(0.8)Ce_(0.2)MnO_3为活性组分,采用共沉淀法制备了La_(0.8)Ce_(0.2)MnO_3/PG,并对其进行XRD、BET、SEM和NH_3-TPD表征。采用固定床催化燃烧装置,考察了不同焙烧温度及La_(0.8)Ce_(0.2)MnO_3负载量的La_(0.8)Ce_(0.2)MnO_3/PG催化剂催化甲苯燃烧的性能。结果表明,当活性组分La_(0.8)Ce_(0.2)MnO_3负载量为15%(质量分数)时,La_(0.8)Ce_(0.2)MnO_3/PG具有较好的催化活性,催化甲苯燃烧的起燃温度T50%和完全转化温度T90%分别为240℃和290℃;600℃焙烧的催化剂活性最佳,比表面积高达109.7m^2/g,表面具有更多酸性位,催化燃烧甲苯的T50%和T90%可低至170℃和250℃。 | 王永强 王坤坤 赵朝成 刘芳 李石 | 2017 | 石油学报(石油加工)2017，33，1： | 2 |
| 7 | Synthesis and characterization of La Ni_xCo_(1–x)O_3: Role of microstructure on magnetic properties显示文摘Perovskite-type structures with the composition La Ni x Co1–x O3(x=0.3, 0.5, 0.7) were synthesized by a modified sol-gel method. Using transitional metal elements on the lanthanum base perovskites, properties could be tuned by doping the structure. Thermogravimetric analysis(TGA) evidenced a temperature of 350 °C as the start point of the perovskite-phase formation. Scanning electron microscopy(SEM) images showed the microstructure changes(grain size) of the cobalt-doped perovskite due to composition. In addition, it was shown that magnetic properties of the samples were dependent of cobalt content; experimental results pointed to the existence of disordered spins interactions, which were more evident with the decrease of cobalt content and the existence of ferromagnetic coupling among spins of the samples. These results showed the feasibility of producing a family of compounds with the desired properties, manipulating composition and therefore the microstructure. | L.Chávez-Guerrero B.Medina-Lott R.F.Cienfuegos M.A.Garza-Navarro R.N.Vannier A.Ringuedé M. Hinojosa M.Cassir | 2015 | Journal of Rare Earths2015，33，3： | 1 |
| 8 | Properties of La_(0.9)Sr_(0.1)MnO_3 and tourmaline compound catalytic materials for methane combustion显示文摘A novel catalytic material La0.9Sr0.1MnO3 and tourmaline compound catalytic material was synthesized in the base of traditional catalytic material La0.9Sr0.1MnO3 which exhibited excellent catalytic activity for methane combustion. Different contents of tourmaline were added to give a series of La0.9Sr0.1MnO3 and tourmaline catalytic material through a sol-gel method. Samples above were characterized and analyzed by means of X-ray diffraction(XRD), scanning electron microscopy(SEM), Brunauer-Emmett-Teller method(BET), temperature programmed reduction(TPR), catalytic activity test and contact angle test. The as-prepared sample with 2%(m/m) tourmaline showed good homogeneity surface morphology and displayed the optimal catalytic activity. The light-off temperature reduced by 10 oC and the T90 decreased by 15 oC. In addition, the mechanism of the reinforcement of catalytic activity was explored. | 薛刚 赵颖 梁金生 苑砚坤 王赛飞 陈丹 | 2014 | Journal of Rare Earths2014，32，9： | 1 |
| 9 | Effect of calcination temperature on steam reforming activity of Ni-based pyrochlore catalysts显示文摘This work served as the second part of a study evaluating the effect of calcination temperature(700-1000℃) on Ni-based lanthanum zirconate pyrochlore catalysts for methane steam reforming.A previous study(Haynes et al.Ceram.Int.2017(43) 16744) provided a thorough characterization of the material properties for the catalysts used here,and this study focuses on the evaluation of catalytic activity.The activity was assessed by two different experimental studies:the effect of reaction temperature using a temperature programmed surface reaction(TPSR),and the effect of reaction pressure.The results demonstrate a complex interaction between the Ni particles and surface LaOx species under the methane steam reforming conditions.Specifically,the material calcined at the lowest temperature(700℃) possesses the highest activity and selectivity,which is attributed to smaller and more welldispersed Ni particles on the surface,and,more importantly,a lesser degree La enrichment at the surface.All catalysts were deactivated by steam to NiO under all conditions tested,but at certain low reaction pressure(p=0.23 MPa) conditions the materials calcined at 700-900℃ are able to completely recover equilibrium activity in-situ that is then robust and stable under both low and high reaction pressures(p=1.8 MPa) suggesting the formation of a synergistic relationship between Ni and La for syngas production.However,exposure of a fresh material to high reaction pressures leads to a rapid and irreversible loss in both CH4 conversion and syngas selectivity whether in the fresh(no pretreatment),or pretreated(steam,H2 or Ar only at 800℃) form for any catalyst.The mechanism for deactivation appears to be due to the presence of LaOx species that become mobile,possibly by the formation of La-OH,and covers the active Ni particles and inhibits sites responsible for the CH4 decomposition. | Daniel J.Haynes Dushyant Shekhawat David Berry Amitava Roy James J.Spivey | 2020 | Journal of Rare Earths2020，38，7： | 0 |
| 10 | 钙钛矿型四效催化剂净化柴油烟气的热力学分析显示文摘根据热力学原理,计算吉布斯自由能的变化量,讨论柴油烟气净化反应的可行性。钙钛矿型四效催化技术是提高CxHy、PM、CO、NOx转化率和降低反应温度的有效方法,也是改变吉布斯自由能变化量ΔG的间接条件。 | 田军吉 刘少光 刘少明 陈成武 吴进明 徐玉松 | 2015 | 环境工程2015，33，S1： | 0 |
| 11 | Wet chemical synthesis of La_(9.83–x)Sr_xSi_6O_(26+δ)(0≤x≤0.50) powders, characterization of intermediate and final products显示文摘In this paper we reported the preparation and extensive characterization of La9.83–x Sr x Si6O26+δ(0≤x≤0.50) precursors, intermediate and final products. The sintering reactions, the phase formation, the structure as well as the powders' morphology were studied by means of thermogravimetric analysis, X-ray diffraction(XRD), Fourier-transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM). Moreover, the effect of stoichiometry on precursor's structure and morphology as well as on intermediate and final products was reported. As was concluded pure La9.83Si6O26+δ, La9.38Sr0.45Si6O26+δ and La9.33Sr0.50Si6O26+δ could be prepared after sintering at 1400 °C for 20 h while La9.68Sr0.15Si6O26+δ and La9.53Sr0.30Si6O26+δ compounds contained minor traces(<3.5%) of La2Si2O7 secondary phase. Concerning the synthesis, there have been no previous reports on the preparation of pure La9.83Si6O26+δ, La9.38Sr0.45Si6O26+δ and La9.33Sr0.50Si6O26+δ compounds. The final powders consisted of spherical particles and an increase of Sr content seemed to inhibit sintering phenomena. The existence of interstitial oxygen at intermediate crystallographic positions of apatite structure had great effect on Si O4 sub-structure distortion. The increase of Sr content led to a major reduction of interstitial oxygen quantity and the refutation of silicon tetrahedron distortion. | Kioupis D. Argyridou M. Gaki A. Kakali G. | 2015 | Journal of Rare Earths2015，33，3： | 0 |
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