On March 13th,Reuters reported that the long run version of Tesla Model 3 will use permanent magnet motors.One of the materials for this type of motor is rare earth metal neodymium,which will further increase the supp...On March 13th,Reuters reported that the long run version of Tesla Model 3 will use permanent magnet motors.One of the materials for this type of motor is rare earth metal neodymium,which will further increase the supply pressure of neodymium.Governments around the world are committed to reducing the harmful emissions produced by fossil fuel cars,pushing up demand for electric vehicles展开更多
The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric a...The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.展开更多
Many carbonate-hosted talc mineralization,which are widespread in South China,exclusively developed in Carboniferous dolomitic limestone with many siliceous bands and nodules,and cherts.One of those typical deposits i...Many carbonate-hosted talc mineralization,which are widespread in South China,exclusively developed in Carboniferous dolomitic limestone with many siliceous bands and nodules,and cherts.One of those typical deposits is the Guling talc deposit in Mashan County,central Guangxi province,with a talc reserve of1.51 million tons.Mineral associations in the deposit are sample,mainly including talc and calcite.In this paper,Sm-Nd isotopic system and rare earth elements and yttrium(REE + Y) for the hydrothermal calcite intergrown with talc are used to constrain the age and origin of the talc mineralization.The hydrothermal calcite samples from the deposit display Sm and Nd concentrations ranging from 0.18 to 0.85 and 0.85 to 4.56 ppm,respectively,and variable Sm/Nd ratios of 0.21-0.24.These calcites further yield an Sm-Nd isochron age of 232 ±19 Ma(2a)(MSWD = 0.47) with an concordant initial ^(143)Nd-^(144)Nd ratios of 0.511967 ± 0.000017,which should be interpreted as the mineralization age of the Guling talc deposit.In addition,the calcite samples are enriched in REE with the variable SREE contents ranging from 4.82 to21.50 ppm and display relatively consistent chondritenormalized REE + Y patterns with the LREE enrichment(LREE/HREE=2.00-3.60)and the obvious negative Eu(δEu=0.52-0.68)and Ce(δCe=0.16-0.33)anomalies.The Y/Ho ratios of seven calcites varies from 43.30 to59.34,with a mean value of 49.73.The available mineral associations and REE parameters(i.e.,REE patterns and Y/Ho ratios) of those calcites indicate that the ore-forming fluids of the talc mineralization be probably derived from the meteoric waters,in particular evolved ones in the Karst areas and the ore-forming materials(e.g.,Si and Mg) are likely to be originated from the ore-bearing dolostone in the Yanguan Formation(C_1y) and underlying siliceous rocks in the Liujiang Formation(D_3l).Furthermore,the talc mineralization could take place within a hydrothermal system with relative oxidizing environment and middle temperature,due to the obvious negative Eu and Ce anomalies in the calcites in the Guling deposit.展开更多
The 2nd International Conference on Rare Earth Development and Applications(ICRE’91),which wassponsored by the Chinese Society of Rare Earths,was held at Beijing International Convention Centre fromMay 27 through May...The 2nd International Conference on Rare Earth Development and Applications(ICRE’91),which wassponsored by the Chinese Society of Rare Earths,was held at Beijing International Convention Centre fromMay 27 through May 31,1991.290 scientists attended this conference,among them there were 63 foreign sci-entists.Prof.Yu Zongsen,vice-chairman of the Chinese Society of Rare Earths,presided over the openingceremony.Mr.Xu Daquan,deputy director of the Rare Earth Leading Group of the State Council,vice-minister展开更多
The title complexes (LnL3 (HL) (H2O) ]2· 2EtOH·2H2O (Ln= Nd (1), La (2), HL=adamantanecarboxylic acid) were prepared and determined by single-crystal X-ray diffraction. Both complexes crystallize ...The title complexes (LnL3 (HL) (H2O) ]2· 2EtOH·2H2O (Ln= Nd (1), La (2), HL=adamantanecarboxylic acid) were prepared and determined by single-crystal X-ray diffraction. Both complexes crystallize in triclinic system with space group P 1^-, cell parameters are: complex (1) a = 1.0556(2) nm, b =1.4913(3) nm, c = 1.4920(3) nm, a = 106.26 (3)°, β=93.51(3)°, γ=97.23(3)°, V=2.2253 (5) nm^3, Dcal=1.409 g · cm^-3, Z = I , F ( 000 ) = 990, μ(Mo Kα) = 1. 225 mm^-1, M, = 1884.50; complex (2) a = 1.0453(2) nm, b = 1.4971(3)nm, c = 1.5052(3) nm, α = 106.07(3)°, β =93.58 (3)°, γ=97.56(3)°, V=2.2391(5)nm^3, Dcal= 1.397 g·cm^-3, Z = 1, F(000) =984, μ(Mo Kα) = 1.015 mm^-1, Mr= 1877.88. The final R and wR are 0. 0396 and 0. 1062 for 8589 (1 ≥ 2σ (I)) observed reflections for complex (1), 0.0505 and 0. 1344 for 8417 ( 1 ≥ 2σ (1) ) observed reflections for complex (2), respectively. The crystals are consisted of a binuelear molecule. The coordination geometry of the Ln( Ⅲ ) ion can be described as trieapped trigonal prism.展开更多
The 2nd Chinese-Soviet Conference on Chemistry and Application Rare Earths was held at ChangchunInstitute of Applied Chemistry, Academia Sinica, and Shanghai Institute of Metallurgy, Academia Sinica,China, on October ...The 2nd Chinese-Soviet Conference on Chemistry and Application Rare Earths was held at ChangchunInstitute of Applied Chemistry, Academia Sinica, and Shanghai Institute of Metallurgy, Academia Sinica,China, on October 5~11, 1991. 10 representatives from USSR attended the conference. There were 47Chinese representatives in Changchun Conference and 77 in Shanghai Conference respectively, Prof. Nijiazan, Chinese chief representative, gave a lecture entitled“Progress and Research on Rare Earth Chemistryin China”, and Prof. I.A. Smirnov gave another lecture entitled“Physico-Chemical Investigation and Per-spective of Practical Application of CeO-PrO”.展开更多
The neodymium complex supported on styrene-maleic anhydride copolymer (SMA·Nd) has been prepared for the first time and found to be a highly effective catalyst for the polymerization of styrene. The SMA·Nd p...The neodymium complex supported on styrene-maleic anhydride copolymer (SMA·Nd) has been prepared for the first time and found to be a highly effective catalyst for the polymerization of styrene. The SMA·Nd polymeric complex is characterized by IR and its catalytic activity, and the polymerization features have been investigated in comparison with that of the conventional Ziegler-Natta catalysts. When [Nd]=1×10^(-3) mol/L, [M]=5mol/L, Al/Nd=170(mol ratio) and CCl_4/Nd=50(mol ratio), the polymerization conversion of styrene gets to 51.6% in six hours, and the catalytic activity reaches 1852 gPS/gNd, which is much higher than that of conventional rare earth catalysts. The polymerization reaction has an induction period and shows some characteristics of chain polymerization. The polymerization rate is the first order with respect to the concentration of styrene monomer. Addition of FeCl_3 does not suppress the polymerization.展开更多
文摘On March 13th,Reuters reported that the long run version of Tesla Model 3 will use permanent magnet motors.One of the materials for this type of motor is rare earth metal neodymium,which will further increase the supply pressure of neodymium.Governments around the world are committed to reducing the harmful emissions produced by fossil fuel cars,pushing up demand for electric vehicles
基金the National Natural Science Foundation of China (50674016)the National High Technology Research and Develop-ment Program of China (863 Program) ( 2006AA06Z123)
文摘The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.
基金funded by The 12th Five Year Plan project of State Key Laboratory of Ore-deposit Geochemistry,Chinese Academy of Sciences(SKLODG-ZY125-04)China Natural Science Foundation(41372105)
文摘Many carbonate-hosted talc mineralization,which are widespread in South China,exclusively developed in Carboniferous dolomitic limestone with many siliceous bands and nodules,and cherts.One of those typical deposits is the Guling talc deposit in Mashan County,central Guangxi province,with a talc reserve of1.51 million tons.Mineral associations in the deposit are sample,mainly including talc and calcite.In this paper,Sm-Nd isotopic system and rare earth elements and yttrium(REE + Y) for the hydrothermal calcite intergrown with talc are used to constrain the age and origin of the talc mineralization.The hydrothermal calcite samples from the deposit display Sm and Nd concentrations ranging from 0.18 to 0.85 and 0.85 to 4.56 ppm,respectively,and variable Sm/Nd ratios of 0.21-0.24.These calcites further yield an Sm-Nd isochron age of 232 ±19 Ma(2a)(MSWD = 0.47) with an concordant initial ^(143)Nd-^(144)Nd ratios of 0.511967 ± 0.000017,which should be interpreted as the mineralization age of the Guling talc deposit.In addition,the calcite samples are enriched in REE with the variable SREE contents ranging from 4.82 to21.50 ppm and display relatively consistent chondritenormalized REE + Y patterns with the LREE enrichment(LREE/HREE=2.00-3.60)and the obvious negative Eu(δEu=0.52-0.68)and Ce(δCe=0.16-0.33)anomalies.The Y/Ho ratios of seven calcites varies from 43.30 to59.34,with a mean value of 49.73.The available mineral associations and REE parameters(i.e.,REE patterns and Y/Ho ratios) of those calcites indicate that the ore-forming fluids of the talc mineralization be probably derived from the meteoric waters,in particular evolved ones in the Karst areas and the ore-forming materials(e.g.,Si and Mg) are likely to be originated from the ore-bearing dolostone in the Yanguan Formation(C_1y) and underlying siliceous rocks in the Liujiang Formation(D_3l).Furthermore,the talc mineralization could take place within a hydrothermal system with relative oxidizing environment and middle temperature,due to the obvious negative Eu and Ce anomalies in the calcites in the Guling deposit.
文摘The 2nd International Conference on Rare Earth Development and Applications(ICRE’91),which wassponsored by the Chinese Society of Rare Earths,was held at Beijing International Convention Centre fromMay 27 through May 31,1991.290 scientists attended this conference,among them there were 63 foreign sci-entists.Prof.Yu Zongsen,vice-chairman of the Chinese Society of Rare Earths,presided over the openingceremony.Mr.Xu Daquan,deputy director of the Rare Earth Leading Group of the State Council,vice-minister
文摘The title complexes (LnL3 (HL) (H2O) ]2· 2EtOH·2H2O (Ln= Nd (1), La (2), HL=adamantanecarboxylic acid) were prepared and determined by single-crystal X-ray diffraction. Both complexes crystallize in triclinic system with space group P 1^-, cell parameters are: complex (1) a = 1.0556(2) nm, b =1.4913(3) nm, c = 1.4920(3) nm, a = 106.26 (3)°, β=93.51(3)°, γ=97.23(3)°, V=2.2253 (5) nm^3, Dcal=1.409 g · cm^-3, Z = I , F ( 000 ) = 990, μ(Mo Kα) = 1. 225 mm^-1, M, = 1884.50; complex (2) a = 1.0453(2) nm, b = 1.4971(3)nm, c = 1.5052(3) nm, α = 106.07(3)°, β =93.58 (3)°, γ=97.56(3)°, V=2.2391(5)nm^3, Dcal= 1.397 g·cm^-3, Z = 1, F(000) =984, μ(Mo Kα) = 1.015 mm^-1, Mr= 1877.88. The final R and wR are 0. 0396 and 0. 1062 for 8589 (1 ≥ 2σ (I)) observed reflections for complex (1), 0.0505 and 0. 1344 for 8417 ( 1 ≥ 2σ (1) ) observed reflections for complex (2), respectively. The crystals are consisted of a binuelear molecule. The coordination geometry of the Ln( Ⅲ ) ion can be described as trieapped trigonal prism.
文摘The 2nd Chinese-Soviet Conference on Chemistry and Application Rare Earths was held at ChangchunInstitute of Applied Chemistry, Academia Sinica, and Shanghai Institute of Metallurgy, Academia Sinica,China, on October 5~11, 1991. 10 representatives from USSR attended the conference. There were 47Chinese representatives in Changchun Conference and 77 in Shanghai Conference respectively, Prof. Nijiazan, Chinese chief representative, gave a lecture entitled“Progress and Research on Rare Earth Chemistryin China”, and Prof. I.A. Smirnov gave another lecture entitled“Physico-Chemical Investigation and Per-spective of Practical Application of CeO-PrO”.
文摘The neodymium complex supported on styrene-maleic anhydride copolymer (SMA·Nd) has been prepared for the first time and found to be a highly effective catalyst for the polymerization of styrene. The SMA·Nd polymeric complex is characterized by IR and its catalytic activity, and the polymerization features have been investigated in comparison with that of the conventional Ziegler-Natta catalysts. When [Nd]=1×10^(-3) mol/L, [M]=5mol/L, Al/Nd=170(mol ratio) and CCl_4/Nd=50(mol ratio), the polymerization conversion of styrene gets to 51.6% in six hours, and the catalytic activity reaches 1852 gPS/gNd, which is much higher than that of conventional rare earth catalysts. The polymerization reaction has an induction period and shows some characteristics of chain polymerization. The polymerization rate is the first order with respect to the concentration of styrene monomer. Addition of FeCl_3 does not suppress the polymerization.