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| 1 | Effects of organic acids on the leaching process of ion-adsorption type rare earth ore显示文摘To examine the activation of organic acids on the leaching process of ion-adsorption type rare earth ore(IRE-ore), the leaching behavior of rare earth(RE) and zeta potential of IRE-ore were investigated in the absence and presence of carboxylic acids. The results show that all the tested organic acids(acetic acid,malonic acid, citric acid, tartaric acid, succinic acid, and malic acid) can promote RE extraction. At relatively high concentrations of organic acids, the activation efficiency of organic acids on RE extraction is generally consistent with their complexation ability; whereas at their low concentrations, the change of zeta potential on the IRE-ore surface with organic acid concentration and p H has a close association with RE extraction, which indicates that organic acids can impact the surface electrical property of IREore via their adsorption/desorption, and thereby increase/decrease the affinity of RE ions to IRE-ore.Therefore the influence of organic acids on the IRE-ore surface electrical property also plays an important role in RE extraction in addition to their complexation with RE ions. | Li Wang Chunfa Liao Youming Yang Haibo Xu Yanfei Xiao Chunhua Yan | 2017 | Journal of Rare Earths2017，35，12： | 23 |
| 2 | Cathodic reduction process of Al-Cu-Y alloy in fluoride-oxide eutectic system via molten salt electrolysis显示文摘Al-Cu-Y alloys were prepared by molten salt electrolysis in fluoride-oxide system composed of electrolyte(Na_3 AlF_6-AlF_3-LiF-MgF_2) and oxide(Al_2 O_3-CuO-Y_2 O_3). Cathodic reduction process of Al_2 O_3,CuO and Y_2 O_3 were analyzed by cyclic voltammetry and chronoamperometry. Components and phase composition of alloy samples prepared by potentiostatic electrolysis were characterized by scanning electron microscopy and energy dispersive spectroscopy. The results show that the Al-Cu-Y alloy can be prepared in the AIF_3-NaF-5 wt%LiF-5 wt%MgF2(NaF/AlF_3 = 2.2, molecular ratio) eutectic system with mixed oxide(Al_2 O_3-CuO-Y_2 O_3) through 2 h at the conditions of a temperature of 1208 K, cell voltage3.0 V, cathode current density 0.7 A/cm^2. Al(Ⅲ) and Cu(Ⅱ) ions can be reduced to zero valence Al(0) and Cu(0) directly on carbonaceous electrode surface by instantaneous nucleation, respectively, the reduction process is controlled by diffusion. The reduction potential of Y(Ⅲ) ions is close to the active ions of fluoride melts, but strengthened phase AI3 Y can be formed through electrochemical reduction and alloyed process with active Al(Ⅲ) and Cu(Ⅱ) ions, meanwhile, the Al_2 Cu and Al_3 Y phases are distributed at the grain boundary of Al matrix. | Xu Wang Chunfa Liao Yunfen Jiao Hao Tang | 2018 | Journal of Rare Earths2018，36，3： | 6 |
| 3 | Electrodeposition of magnesium-yttrium alloys by molten salt electrolysis显示文摘 | Shaohua YANG Fengli YANG Chunfa LIAO Mingzhou Li Xu WANG | 2010 | Journal of Rare Earths2010，，： | 1 |
| 4 | Electrodeposition of magnesium-yttrium alloys by molten salt electrolysis显示文摘 | Shaohua YANG Fengli YANG Chunfa LIAO Mingzhou Li Xu WANG | 2010 | Journal of Rare Earths2010，，： | 1 |
| 5 | Density of Na3AIF6-AIF3-LiF-MgF2-Al2O3-Sm2O3 molten salt melt for Al-Sm alloy显示文摘Samarium(Sm) has been widely used in making aluminum(Al)-Sm magnet alloy materials. The research team for this study developed a molten salt electrolyte system which directly produces AI-Sm alloy to replace the energy intensive conventional distillation technology. In this study, molten melt density was measured and operation conditions were optimized to separate AI-Sm alloy product from the fluoride molten melt electrolysis media based on density differences, Archimedes' principle was applied to measure density for the basic molten fluoride system(BMFS: Na_3 AlF_6-AlF_3-LiF-MgF_2)electrolysis media in the temperature range from 905 to 1055 ℃.The impact of temperature(t) and the Al_2O_3 and Sm_2O_3 addition ratio(w_((Al2O3)),w_((Sm2O3)) in the basic fluoride system on molten melt density was examined. The fluoride molten melt density relationship was determined to be:ρ=3.11701-0.00802 w_((Al2O3))+0.027825 w_((Sm2O3))-0.00117 t. The test results showed that molten density decreases with increase in temperature and Al_2O_3 addition ratio, and increases with the addition of Sm_2O_3, and/or Al_2O_3+Sm_2O_3. The separation of Al-Sm(density 2.3 g/cm^3) product melt from the BMFS melt is achieved by controlling the BMFS density to less than 2.0 g/cm3. It is concluded that the optimal operation conditions to control the BMFS molten salt density to less than 2.0 g/cm^3 are:maintain addition of Al_2O_3+Sm_2 O_3(w_((Al2O3))+w_((Sm2O3))<9% of Na_3AlF_6,Al_2O_3/Sm_2O_3 ratio(w_((Al2O3)):w_((Sm2O3)))> 7:3, and temperature between 965 and 995 ℃. | Yunfen Jiao Xu Wang Chunfa Liao Jia Su Hao Tang Boqing Cai Qiangchao Sun | 2018 | Journal of Rare Earths2018，36，2： | 1 |
| 6 | Identification of ions present in LiF-DyF_3 melts and the mechanism of Dy_2O_3 dissolution therein显示文摘Herein, the present paper were attempted to identify ions in LiF-DyF_3 melts according to the law of decreasing primary crystallization temperature and model analysis. Specifically.the primary crystallization temperatures of LiF-DyF_3 and LiF-DyF_3-Dy_2O_3 melts with various DyF_3 and Dy_2O_3 contents were determined by differential scanning calorimetry(DSC), and reactions occurring in the above melts were investigated using ideal dilute solution(Temkin and Flood) models. Moreover, crystal phases produced by rapid solidification of LiF-DyF_3, LiF-Dy_2O_3, DyF_3-Dy_2O_3, and LiF-DyF_3-Dy_2O_3 melts were identified by X-ray diffraction(XRD) analysis. The primary crystallization temperature of LiF-DyF_3 melts exhibits an approximately linear decrease with increasing molar fraction of DyF_3, and the general formula of complex ions in these melts is expressed as DyF_x^((3-x)),e.g., DyF_4^-. Finally, we investigated the dissolution of Dy_2O_3 in LiF-DyF_3 melts, showing that it was chemical in nature and afforded Dy_(1+x)O_(3x)F_(3-3x) and DyOF. | Chunfa Liao Shumei Chen Xu Wang Boqing Cai Jueyuan Lin Yunfen Jiao Yanliang Zeng | 2019 | Journal of Rare Earths2019，37，2： | 1 |
| 7 | Palladium-Catalyzed Cross-Coupling of Fluorinated Vinyl Chlorides with Terminal Alkynes: A General Protocol to Fluorinated Enynes显示文摘为氟化的结合的 enynes 的准备的一个有效、划算的方法被描述。方法与象氯化物,胺, cyano 和酉旨组那样的许多功能的组兼容。方法能也被扩大到联合(R, Z ) 有中等收益的 -3-(2-chloro-1,2-difluorovinyl)-4-alkyloxazolidin-2-one (3 ) 。 | Sheng Chen Chunfa Xu Long Lu Qilong Shen | 2013 | Chinese Journal of Chemistry2013，31，7： | 0 |
| 8 | Skeletal contraction:A novel strategy to access multisubstituted cyclobutane显示文摘The polysubstituted and spirocyclic cyclobutanes were efficiently constructed by the utilization of a novel skeletal contraction strategy which only took one-step synthesis from the readily accessible pyrrolidines.The mechanistic studies indicated that a key intermediate N-aminated pyrrolidine was formed initially and subsequent extrusion of a nitrogen via a radical pathway completed the transformation.This practical methodology was further highlighted by the concise,formal synthesis of the cytotoxic natural product piperarborenine B. | Chunfa Xu V.U.Bhaskara Rao Fen-Er Chen | 2022 | Green Synthesis and Catalysis2022，3，1： | 0 |
| 9 | Nucleophilic Trifluoromethylthiolation of Alkyl Chlorides, Bromides and Tosylates显示文摘有 AgSCF 3 的烷基氯化物,溴化物和 tosylates 的直接亲核的 trifluoromethylthiolation 被描述。这被发现 nBu 4 NI 或 nBu 4 NI/nBu 4 NBr 显著地提高了反应率。反应条件是温和的,因此允许许多功能的组的忍耐。 | Chunfa Xu Qingyun Chen Qilong Shen | 2016 | Chinese Journal of Chemistry2016，34，5： | 0 |
| 10 | Molecular editing in natural product synthesis显示文摘Many natural products have remarkable biological functions due to their fascinating molecular architectures.Despite many advances in synthetic method development,the efficient synthesis of highly functionalized and structurally intricate natural products to meet the demand for biological investigations remains a daunting challenge.Molecular editing encompassing insertion,deletion,or exchange of atoms of highly functionalized compounds has emerged as a hotspot in new method development and has been applied in complex natural product synthesis.In this highlight,the latest developments in molecular editing in natural product synthesis are discussed. | Chunngai Hui Zhuo Wang Shiping Wang Chunfa Xu | 2022 | Organic Chemistry Frontiers2022，9，5： | 0 |
| 11 | Assembly and analysis of the Populus deltoides mitochondrial genome:the first report of a multicircular mitochondrial conformation for the genus Populus显示文摘Genomics research of Populus deltoides,an important timber species that is widely planted worldwide,is an important part of poplar breeding.Currently,the nuclear and chloroplast genome of P.deltoides have been sequenced,but its mitochondrial genome(mitogenome)has not been reported.To further explore the evolution and phylogeny of P.deltoides,the mitogenome of P.deltoides I-69 was assembled using reads from Nanopore and Illumina sequencing platforms and found to consist of 802,637 bp and three circular chromosomes(336,205,280,841,and 185,591 bp)containing 58 genes(34 protein-coding genes,21 tRNA genes,and 3 rRNA genes).RNA analysis in combination with several species showed signifi cantly fewer RNA editingsites in the mitogenomes of poplar and other angiosperms than in gymnosperms.Sequence transfer analysis showed extensive mitogenome rearrangements in Populus species,and with evolution from lower to higher plants,tRNA transfer from chloroplasts to mitochondria became increasingly frequent.In a phylogenetic analysis,the evolutionary status of P.deltoides was determined,and the section Populus was supported.Our results based on the fi rst report of a multicircular conformation of the Populus mitogenome provide a basis for further study of the evolution and genetics of P.deltoides and other Populus species and for breeding programs. | Yanshu Qu Pengyan Zhou Chunfa Tong Changwei Bi Li’an Xu | 2023 | Journal of Forestry Research2023，34，3： | 0 |
| 12 | Synergistic Pd/Cu catalysis enabled cross-coupling of glycosyl stannanes with sulfonium salts to access C-aryl/alkenyl glycals显示文摘A highly efficient coupling of glycosyl stannanes and sulfonium salts enabled by synergistic Pd/Cu catalysis is disclosed, facilitating the construction of C-aryl/alkenyl glycals under mild conditions in high yields.The protocol tolerates a wide scope of functional groups including ketone, cyano, ester, amide, nitro,halide. The one-pot formal C–H glycosylation starting from arene is demonstrated with a reaction sequence of dibenzothiophenylation/Stille coupling. Besides, a gram-scale reaction is performed successfully,showing the high applicability of this protocol. | Weitao Yan Mingwen Zheng Peihsuan Chuang Hao Sun Shiping Wang Chunfa Xu Fen-Er Chen | 2023 | Chinese Chemical Letters2023，34，7： | 0 |
| 13 | Dinitrogen extrusion from diazene in organic synthesis显示文摘Radical-mediated reactions have many advantages in the construction of complex molecular scaffolds by forging chemical bonds of high challenge.Diazenes,including 1,1-diazenes and 1,2-diazenes,can generate biradical species via nitrogen extrusion under thermal or photochemical conditions.The superior reactivity of the generated biradical enables various types of synthetic transformations with excellent chemoselectivity and has been applied to the complex natural products synthesis.In this mini-review,the modes of reaction are summarized and discussed,namely ring contraction via nitrogen deletion,homo or heterodimerization,trimethylenemethane(TMM)-diyl cycloaddition.Applications of these classes of reactions in complex natural product synthesis are illustrated.Last but not least,the current state,future directions,and opportunities for dinitrogen extrusion reaction from diazenes are highlighted and discussed. | Chunngai Hui Shiping Wang Chunfa Xu | 2022 | Chinese Chemical Letters2022，33，8： | 0 |
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