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Journal of Rare Earths 2024年第6期42卷 1036-1045,I0002页

作者： Yuefei Xiang Hong Li Hongzhi Zhang Lin Yang Canyuan Liao Tongsheng Yang Junpeng Li Zewen Guo Jing Zhu Key Laboratory of LCR Materials and Devices of Yunnan ProvinceYunnan Key Laboratory of Carbon Neutrality and Green Low-carbon TechnologiesSchool of Materials and Energy Yunnan University Kunming650091China

At present,with the increasing application needs of phosphor-converted white light-emitting diode(wLED),the synthetic efficiency and thermal stability of phosphor become urgent problems.Herein,this research reports a microwave-assisted fast synthesis approach to obtain a Sm^(3+)-activated borotellurate Na_(2)Y_(2)TeO_(4)(BO_(3))_(2)(NYTB)red phosphor with high crystallinity,excellent thermostability,and low chromaticity shift.For the NYTB-based phosphor,in contrast to the conventional solid-state synthesis,the microwave-assisted synthesis method involves lower synthesis temperature and shorter processing time.Additionally,the concentration quenching mechanism was determined.The w-LED device packaged with the studied phosphor exhibits a near-standard white light with proper CCT and high Ra parameters.

关键词： Borotellurate samarium Microwave-assisted synthesis Red-emitting Thermal stability Rareearths

Luminescence of samarium doped hydroxyapatite containing strontium:Effects of doping concentration

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Journal of Rare Earths 2022年第3期40卷 398-405,I0002页

作者： Pu Chen Fen Wang Yinpo Qiao Zhen Zhang Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi'an 710021China

A series of samarium(Sm)doped hydroxyapatites containing strontium(Sr)with controllable and adjustable luminescence were designed and prepared via chemical hydrolysis co-precipitation method.The effects of doping concentration of Sm on the structure,composition,photoluminescence(PL),energy transfer,substitute site,fluoresce lifetime and luminescence color of samples were investigated.It is shown that the introduction of Sr ions induces the structure and composition change for Sm doped samples.The typical transitions of Sm^(3+) at 564,601,648 and 707 nm due to^(4)G_(5/2)→^(6)H_(J/2)(J=5,7,9 and 11)transition under the excitation of 404 nm were detected.The PL intensity is affected by the Sr/Ca ratio and Sm concentration,and the optimal concentration of Sm is 0.8 mol%when Sr/Ca ratio equals 7/3.The non-radiative transitions and energy transfer of Sm ions are the main reason for the quenching,and the interactions among ions are ascribed to dipole-dipole type by theoretical calculation.Besides,the ratio of PL intensity between 601 and 648 nm(r_(O/R)=I_(601nm)/I_(648nm))indicates the symmetry and substitution process of Sm ions to Ca/Sr ions.The fluorescence lifetime(τ)decreases with the concentration of Sm increasing,which is the result of the decrease of distance and the enhanced interaction between Sm ions.The CIE chromaticity coordinates and luminescence color of samples are in the orange-red region and have close relation with the concentration of Sm.Furthermore,the cytotoxicity evaluation and confocal laser scanning microscopy(CLSM)observation of samples via cells indicate the good biocompatibility and safe use of this kind of bio-based luminescent materials for their potential efficient fluorescence labeling and detection.

关键词： samarium Strontium Hydroxyapatite Photo-luminescence Energy transfer Cytotoxicity evaluation

Effect of samarium on the N_(2) selectivity of Sm_(x)Mn_(0.3-x)Ti catalysts during selective catalytic reduction of NO_(x) with NH_(3)

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 642-652页

作者： Shengyang Zhang Bolin Zhang Boyu Wu Bo Liu Shengen Zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China

This work aims to study the improvement effect of Sm on Mn-based catalysts for selective catalytic reduction (SCR) of NO with NH3.A series of Sm_(x)Mn_(0.3-x)-xTi catalysts (x=0,0.1,0.15,0.2,and 0.3) were prepared by co-precipitation.Activity tests indicated that the Sm_(0.15)Mn_(0.15)Ti catalyst showed superior performances,with a NO conversion of 100%and N_(2)selectivity above 87%at 180–300℃.The characterizations showed that Sm doping suppressed the crystallization of TiO_(2)and Mn2O3phases and increased the specific surface area and acidity.In particular,the surface area increased from 152.2 m^(2)·g^(-1)for Mn0.3Ti to 241.7 m^(2)·g^(-1)for Sm_(0.15)Mn_(0.15)Ti.These effects contributed to the high catalytic activity.The X-ray photoelectron spectroscopy (XPS) results indicated that the relative atomic ratios of Sm^(3+)/Sm and Oβ/O of Sm_(0.15)Mn_(0.15)Ti were 76.77at%and 44.11at%,respectively.The presence of Sm contributed to an increase in surface-absorbed oxygen (Oβ) and a decrease in Mn^(4+)surface concentration,which improved the catalytic activity.In the results of hydrogen temperature-programmed reduction(H_(2)-TPR),the presence of Sm induced a higher reduction temperature and lower H_(2)consumption (0.3 mmol·g^(-1)) for the Sm_(0.15)Mn_(0.15)Ti catalyst compared to the Mn0.3Ti catalyst.The decrease in Mn^(4+)weakened the redox property of the catalysts and increased the N_(2)selectivity by suppressing N_(2)O formation from NH3oxidation and the nonselective catalytic reduction reaction.The in situ diffuse reflectance infrared Fourier transform spectra (DRIFTs) revealed that NH3-SCR of NO over the Sm_(0.15)Mn_(0.15)Ti catalyst mainly followed the Eley–Rideal mechanism.Sm doping increased surface-absorbed oxygen and weakened the redox property to improve the NO conversion and N_(2)selectivity of the Sm_(0.15)Mn_(0.15)Ti catalyst.

关键词： manganese oxides nitric oxide nitrous oxide samarium selective catalytic reduction nitrogen selectivity

samarium mediated pinacol coupling of carbonyl compounds in the presence of a catalytic amount of iodine under aqueous media

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Chinese Journal of Chemistry 1999年第5期17卷 550-553,428页

作者：王磊张永敏 Department of Chemistry Zhejiang University at Xixi Campus Hangzhou Zhejiang 310028 China

In the presence of a catalytic amount of iodine, metallic samarium mediated pinacol coupling of carbonyl compounds has been carried out under saturated aqueous Nl&Cl-THF conditions at mom temperature. It gives corresp... 详细信息

关键词： samarium iodine pinacol coupling aqueous media

Optimized preparation of zinc-inorganic antibacterial material containing samarium using response surface methodology

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Journal of Rare Earths 2014年第9期32卷 900-906页

作者：毛翠萍张彬唐晓宁李欢何素琼 Faculty of Science Kunming University of Science and Technology Institute for Clean Energy and Advanced Materials South-west University Faculty of Chemical Engineering Kunming University of Science and Technology

A Box-Behnken design （BBD） of response surface methodology （RSM） was used to optimize the preparation of the Zn-Sm antibacterial white carbon black by the sol-gel method. The statistical analysis of the results showed that the particle size of the Zn-Sm antibacterial white carbon black was significantly affected by the reaction time, reaction temperature and the stirring speed. According to analysis of variance （ANOVA）, the values of the determination coefficient （R2=0.9821） and the ＂Pred R-Squared＂ of 0.8227 were in reasonable agreement with the ＂Adj R-Squared＂ of 0.9591. It was indicated that this model could be used to navigate the design space. The optimized reaction time, temperature and the stirring speed were 0.88 h, 87.83 ℃, and 473.45 r/rain, respectively. In addition, the bacteriostasis rate of the product was about 97.92%.

关键词： response surface inorganic antibacterial material zinc ion samarium rare earths

Electrochemistry of samarium in lithium-beryllium fluoride salt mixture

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Journal of Rare Earths 2011年第8期29卷 798-803页

作者： Martin Straka Michal Korenko Frantisek Lisy Lórant Szatmáry Department of Fluorine Chemistry Nuclear Research Institute Rez plc 250 68 Husinec-Rez 130 Czech Republic Institute of Inorganic Chemistry Slovak Academy of Sciences Dubravska cesta 9 SK-845 36 Bratislava Slovakia

The electrochemical behaviour of samarium was investigated in LiF-BeF2 system on an inert （Mo） electrode by cyclic voltammetry and chronopotentiometry at 804, 833, 847 and 872 K. Redox process Sm3＋＋e–→Sm2＋ was recognized and analysed. Cyclic voltammetry data suggested that at potential sweep rates lower than 0.25 V/s, the reduction was limited by the diffusion of Sm3＋ ions. It was not possible to observe reduction process of Sm2＋＋2e–→Sm0 due to insufficient electrochemical stability of LiF-BeF2. Diffusion coefficients of Sm3＋ ions in LiF-BeF2 were calculated from voltammetric and chronopotentiometric data in the temperature range 804–872 K. Diffusion coefficient values obeyed Arrhenius law. Activation energy was calculated to be 102.5 kJ/mol.

关键词： spent fuel reprocessing pyrochemical partitioning electrochemical separation molten fluorides LiF-BeF2 samarium rare earths

Effects of samarium content on microstructure and mechanical properties of Mg–0.5Zn–0.5Zr alloy

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Journal of Materials Science & Technology 2019年第7期35卷 1368-1377页

作者： Kai Guan Fanzhi Meng Pengfei Qin Qiang Yang Dongdong Zhang Baishun Li Wei Sun Shuhui Lv Yuanding Huang Norbert Hort Jian Meng State Key Laboratory of Rare Earth Resource Utilization. Changchun Institute of Applied Chemistry Chinese Academy of Science Changchun 130022 University of Science & Technology of China Hefei 230026China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Superlight Material and Surface Technology Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China MagIC-Magnesium Innovation Centre Helmholtz-Zentrum GeesthachtMax-Planck Strasse 121502CeesthachtGermany

Effects of samarium (Sm) content (0, 2.0, 3.5, 5.0, 6.5 wt%) on microstructure and mechanical proper-ties of Mg-0.5Zn-0.5 Zr alloy under as-cast and as-extruded states were thoroughly investigated. Results indicate that grains of the as-cast alloys are gradually refined as Sm content increases. The dominant intermetallic ph^se changes from Mg3Sm to Mg4iSm5 till Sm content exceeds 5.0 wt%. The dynami-cally precipitated intermetallic phase during hot-extrusion in dll Sm-containing alloys is Mg3Sm. The intermetallic particles induced by Sm addition could act as heterogeneous nucleation sites for dynamic recrystallization during hot extrusion. They promoted dynamic recrystallization via the particle stim-ulated nucleation mechanism, and resulted in weakening the basal texture in the as-extruded alloys. Sm addition can significantly enhance the strength of the as-extruded Mg-0.5Zn-0.5Zr alloy at room temperature, with the optimal dosage of 3.5 wt%. The optimal yield strength (YS) and ultimate tensile strength (UTS) are 368 MPa and 383 MPa, which were enhanced by approximately 23.1% and 20.8% com-pared with the Sm-free alloy, respectively. Based on microstructural analysis, the dominant strengthening mechanisms are revealed to be grain boundary strengthening and dispersion strengthening.

关键词： Magnesium alloys samarium Transmission electron microscopy (TEM) Microstructure Mechanical properties

Synthesis of Thioproline Salicylic Acid samarium Complex and Microcalorimetric Study on Effects of the Complex on the Growth Metabolism of S. pombe Cells

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Chinese Journal of Chemistry 2011年第11期29卷 2285-2292页

作者：李强国张辉李旭王彬胡吉林姚飞虹杨德俊肖圣雄叶丽娟 Department of Chemistry and Life Science Xiangnan University Chenzhou Hunan 423043 China Hunan Key Laboratory of the Investigation of Biological Medicine and Complexes of Non-ferrous Metal Xiangnan University Chenzhou Hunan 423043 China

The product from reaction of samarium chloride hexahydrate with salicylic acid and thioproline, [Sm（C7H503）2·（CaH6NO2S）]-2H20 （TSAS）, was synthesized and characterized by IR, elemental analysis and ther- mogravimatric analysis. Particularly, the effect of the compounds TSAS, SmCl3·6H2O, C7H6O3 and C4HTNO2S on the growth and metabolism of S. pombe by a TAM Air isothermal calorimeter at 32 ~C is also reported. The ther- mokinetic parameters, which included the microbial growth rate constant （x）, inhibition ratio （/） and half inhibition concentration （IC50）, were obtained. The results showed that all the compounds TSAS, SmC13.6H20, C7H603 and CaHTNO2S possessed the bi-directional biological effect and Hormesis effect. These stimulate the growth of the S. pombe at lower concentration, but inhibit the growth at higher concentration. The half inhibition concentrations （IC50） of TSAS, SmCl3·6H2O, CnH7NO2S and C7H603 were found to be 0.732, 0.746, 0.746 and 1.43 mmol·L-1, respectively. The inhibition ability of these compounds on the growth of the S. pombe has been observed to decrease in the order TSAS 〉 SmCl3·6H2O = CaH7NO2S〉C7H6O3. Moreover, the effect of TSAS on the growth and cytokinesis of S. pombe was investigated by cytomorphology and FT IR spectroscopy technique. The results indicated that TSAS had a direct impact on apoptosis, and could also inhibit the cell growth by reducing cytokinesis and the binding locations of drug （TSAS） in S. pombe cells could be the proteins and nucleic acid.

关键词： samarium medicinal chemistry thermokinetic metabolism rare earths

Effects of calcium, samarium addition on microstructure and mechanical properties of AZ61 magnesium alloy

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Journal of Rare Earths 2015年第1期33卷 86-92页

作者：陈玉安金李方丹宋裕叶睿宇 College of Materials Science and Engineering Chongqing University

The microstructure and mechanical properties of AZ61 magnesium alloy with Ca, Sm addition were investigated. The results showed that the addition of 0.5 wt.% Ca reduced the quantity of Mg17Al12 phase, and formed a new Al4 Ca phase which is reticular in AZ61 alloy. With the addition of Ca and Sm, the microstructure was further refined and new Al-Sm rich phases were formed in AZ61 alloy with 0.6 wt.%-1.5 wt.% Sm addition, the TEM analysis confirmed that they were Al2 Sm and Al4 Sm. Tensile tests showed that 1.0 wt.% Sm addition contributed to the formation of the Al2 Sm and Al4 Sm and the improvement in the ambient strength, i.e., an ultimate tensile strength of 327 MPa and an elongation of 10.1%. However, excessive Sm addition led to the coarsening of Al2 Sm and Al4 Sm phases, thus resulted in the decline of strength and plasticity.

关键词： AZ61 magnesium microstructure mechanical properties samarium rare earths

Removal of trivalent samarium from aqueous solutions by activated biochar derived from cactus fibres

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Journal of Rare Earths 2016年第1期34卷 99-104页

作者： Loukia Hadjittofi Styliana Charalambous Ioannis Pashalidis Department of Chemistry University of Cyprus

The efficiency of activated biochar fibres obtained from Opuntia Ficus lndica regarding me sorpuon oi trlvalent samarium （Sm（Ⅲ）） from aqueous solutions was investigated by batch experiments. The effect of various physicochemical parameters （e.g. pH, initial metal concentration, ionic strength, temperature and contact time） on the Sm（III） adsorption was studied and the surface species were characterized by FTIR spectroscopy prior to and after the lanthanide sorption. The experimental results showed that the acti- vated biochar fibres possessed extraordinary sorption capacity for Sm（Ⅲ） in acidic solutions （qmax=90 g/kg, pH 3.0） and near neutral solutions （qmax=350 g/kg, pH 6.5）, This was attributed to the formation of samarium complexes with the surface carboxylic moieties, available in high density on the lamellar structures of the bio-sorbent.

关键词： samarium waters activated biochar fibres enhanced sorption capacity FTIR spectra rare earths