The effects of rare earth samarium （Sm） additions on the microstructure and mechanical properties of as-cast Al-Si-Cu alloy were investigated by optical microscopy and scanning electron microscopy （SEM）. The resul...The effects of rare earth samarium （Sm） additions on the microstructure and mechanical properties of as-cast Al-Si-Cu alloy were investigated by optical microscopy and scanning electron microscopy （SEM）. The results show that Sm can effectively refine the a（Al） dendrite and the eutectic silicon. In addition, the shape of iron-rich phases changes from the Chinese script-like to slender-like ones and the volume fraction of iron-rich phases is decreased by the addition of Sm. Two kinds of Sm-rich interrnetallics are found： AlSiSm and AlSiCuSm. The plate-like AlSiCuSm phase always associates with the needle-like AISiSm phase. The mechanical properties are improved by the addition of Sm, and the good ultimate tensile strength （220 MPa） and elongation （3. 1%） are obtained from the Al-Si-Cu-1.0Sin alloy.展开更多
Trivalent samarium ion (Sm^(3+)) activated calcium molybdate (CaMoO_4) phosphor was prepared by solid-state reaction in air. The XRD pattern of the powder CaMoO_4∶Sm shows that the CaMoO_4∶Sm single phase is develop...Trivalent samarium ion (Sm^(3+)) activated calcium molybdate (CaMoO_4) phosphor was prepared by solid-state reaction in air. The XRD pattern of the powder CaMoO_4∶Sm shows that the CaMoO_4∶Sm single phase is developed fully through our preparation procedure. The excitation spectrum of CaMoO_4∶Sm is composed of a broad absorption of host and some sharp lines of the f-f transition absorption of Sm^(3+). Illustrated in photoluminescence spectrum, CaMoO_4 doped with Sm^(3+) displays orange red emission that is ascribed to the inner 4f^5 electron transitions ~6H_(7/2)(orange)and ~6H_(9/2)(red)of Sm^(3+). Different from the sites of Sm^(3+) in CdWO_4, the Sm^(3+) ions substitute for the Ca^(2+) and form only one type emission center in the CaMoO_4 crystal lattice.展开更多
Nanometer crystal samarium borate with a particle size of 20～40?nm was prepared using replacing solvent drying technique. The wear resistance and load carrying capacity of 500SN base oil could be improved and the fri...Nanometer crystal samarium borate with a particle size of 20～40?nm was prepared using replacing solvent drying technique. The wear resistance and load carrying capacity of 500SN base oil could be improved and the friction coefficient could be decreased by the addition of nanometer samarium borate. But the dosage of samarium borate nanoparticles had to be controlled at a relatively low level, a higher concentration of nanoparticles was not of beneficial to the tribological performance of the oil. The optimal dosage of nanometer samarium borate is 1.0%. Tribochemical reactions took place in the tribological process, which resulted in the formation of deposition products including diboron trioxide and disamarium trioxide. Fe 2B and FeB were also found on the wear scar. The improvement of tribological properties of the oil comes from the formation of deposition layer and permeating layer. [展开更多
Spraque-Dawley(SD)big rats with weaning weight of (195±15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drank de-ionized water served as control and also used for analysi...Spraque-Dawley(SD)big rats with weaning weight of (195±15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drank de-ionized water served as control and also used for analysis with the background. The other three groups were cultured for five months by drinking de-ionized water with 3.0, 4.5 and 6.0 mg·L-1 Sm (NO3)3, respectively. Compared with the rats in control, it is found that the organs of the treated rats are apparently pathologically changed, such as liver swell, lung intumescence, peritoneum conglutination and hardness. Especially, in the high Sm group, the pathological percentage in liver and lung is up to 30% . The pathological changes in liver and lung show that rare earth Sm does hazard biological effects to animals. With increasing Sm concentration, the weight rate of organ/body has a tendency of increasing; the activity of superoxide dismutase (SOD) in liver and kidney decreases, but the maglonydiadehyde (MDA) concentration increases, indicating the abilities of anti-oxidation and the lipid per-oxi-dation inhibition degenerate, which leads to hard pathological changes in organs. Moreover, the relative weight rate of organ/body, the activity of SOD and the MDA concentration are remarkably lager in liver than in kidney and other organs, suggesting that the biological effect of Sm on liver is the greatest and Sm has a high affinity for liver.展开更多
The polymerization of acrylonitrile initiated by organolanthanide complexes alone is studied for the first time. The effect of polymerization conditions on catalytic activity of the title complex and molecular weight ...The polymerization of acrylonitrile initiated by organolanthanide complexes alone is studied for the first time. The effect of polymerization conditions on catalytic activity of the title complex and molecular weight of the polymers produced have been studied.展开更多
The mechanical properties of Al-Cu-Mn casting alloy mainly depend on the morphology, distribution, size, and number ofθ′（Al2Cu） precipitates. In this study, we have analyzed the effect of rare earth samarium （Sm...The mechanical properties of Al-Cu-Mn casting alloy mainly depend on the morphology, distribution, size, and number ofθ′（Al2Cu） precipitates. In this study, we have analyzed the effect of rare earth samarium （Sm） addition on the kinetics of precipitation in the Al-Cu-Mn casting alloy by using differential scanning calorimetry （DSC） and high-resolution transmission electron microscopy. Thermal ef-fect peaks that are attributed to the formation and the dissolution of Guinier-Preston （GP） zone andθ′phase were identified from the DSC curves. The activation energy ofθ′formation was calculated by using both the Kissinger method and the analytical model, and the corre-sponding results were compared. Results suggest that the activation energy ofθ′formation in Al-Cu-Mn alloy is dramatically higher than that in Al-Cu-Mn-Sm alloy. Accordingly, it is concluded that the addition of rare earth Sm decreases the activation energy ofθ′formation and promotes the formation ofθ′precipitates.展开更多
A novel 1064 tun laser stealth absorbent of SmzO2S was prepared by flux method. The effects of different calcining temperatures and fluxes on the reflective property of Sm2O2S were investigated. The phase composition,...A novel 1064 tun laser stealth absorbent of SmzO2S was prepared by flux method. The effects of different calcining temperatures and fluxes on the reflective property of Sm2O2S were investigated. The phase composition, morphology, and reflectivity of the powders were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and ultraviolet-visible spectrophotometer （UVPC）. The results showed that pure phase of Sm202S could be obtained with Na2CO3 as flux above 950~C, and the reflectivity decreased with the calcination temperature increasing. Compared with other samarium compounds, the reflectivity at 1064 nm of Sm2O2S was the lowest. Different fluxes had great impact on the phase composition, particle morphology, and reflectivity of the products. In short, Sm2O2S was suitable as a kind of absorbent against 1064 nm laser.展开更多
The coordination complex Sm（C7H5O2）2·（C9H6NO）, synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline, was characterized with IR, elemental analysis, molar co...The coordination complex Sm（C7H5O2）2·（C9H6NO）, synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline, was characterized with IR, elemental analysis, molar conductance, and thermogravimatric analysis. The standard molar enthalpies of solution of [ SmCl3·6H2O （s） ], [ 2C7H6O3 （s） ], [ C9H7NO （ s ） ] and [ Sm （C7H5O3） 2·（ C9H6NO ） （ s ） ] in the calorimetric solvent were determined with the solution-reaction isoperibol calorimeter at 298.15 K to be △sHm^- [ SmCl3·6H2O （s）, 298.15 K ] = - 103.98 ± 0.04 kJ·mol^-1, △sHm^- [2 C7H6O3 （s）, 298.15 K] = 16.35±0.14 kJ·mol^-1,△sHm^-[C9H7NO （s）, 298.15 K] = -6.11±0.08 kJ·mol^-1 and △sHm^-[Sm（C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 130.08 ± 0.04 kJ·mol^-1, respectively. The enthalpy was determined to be △rHm^- = 89.59 ±0.18 kJ·mol^-1 for the reaction SmCl3·6H2O（s） ＋ 2C7H6O3（s） ＋ C9H7NO（s） = Sm （C7H5O3） 2·（C9H6NO） （ s ） ＋ 3HCl （g） ＋ 6H2O （ l ）. According to the above results and the data given in literature and through Hess＇ law, the standard molar enthalpy of formation of Sin（ C7H5O3 ）2·（C9H7NO）（s） was estimated to be △rHm^- [ Sm （C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 2055.9 ± 3.03 kJ·mol^-1.展开更多
The intermolecular reductive coupling of nitrites with azobenzene induced by SmI2 was studied. Amidine derivatives were prepared in good yields under neutral and mild conditions.
The present paper contains the reaction mechanism of the rare earth complex with 2-(2-arsenophenylazo)-7-(2, 6-dichloro-4-fluoro-phenylazo)- 1, 8-dihydroxynaphthalene-3, 6-disulfonic acid (DCF-arsenazo) studied prelim...The present paper contains the reaction mechanism of the rare earth complex with 2-(2-arsenophenylazo)-7-(2, 6-dichloro-4-fluoro-phenylazo)- 1, 8-dihydroxynaphthalene-3, 6-disulfonic acid (DCF-arsenazo) studied preliminarily with a fully automated stopped-flow analyzer. A method with a high sensitivity and selectivity is proposed for the simultaneous determination of samarium and gadolinium based on the differential kinetic reaction of the rare earth complex with DCF-arsenazo. Sm and Gd in their concentrated oxides were determined with the relative errors less than 6%.展开更多
The reduction of disulfides by samarium diiodide led to sa arium thiolates (ArSSml2).This new thiolate anion species reacted smoothly with α, β -unsaturated esters (nitriles) to give 1,4-addition products β -thioes...The reduction of disulfides by samarium diiodide led to sa arium thiolates (ArSSml2).This new thiolate anion species reacted smoothly with α, β -unsaturated esters (nitriles) to give 1,4-addition products β -thioesters and β -thionitriles in good yields under mild and neutralcondition.展开更多
Two crystals, [Sm（Hcpna）（cpna）·3 H2O]n（1） and [Eu（Hcpna）（cpna）·2 H2O]n（2）,have been synthesized by solvothermal method based on Sm3+ and Eu3+ with multiple acid ligands5-（4-carboxyphenoxy）nicot...Two crystals, [Sm（Hcpna）（cpna）·3 H2O]n（1） and [Eu（Hcpna）（cpna）·2 H2O]n（2）,have been synthesized by solvothermal method based on Sm3+ and Eu3+ with multiple acid ligands5-（4-carboxyphenoxy）nicotinic acid（H2cpna）, and the new complexes have been characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, thermogravimetric analysis and fluorescence analysis. Complex 1 exhibits a 1 D chain structure. It crystallizes in the triclinic system, space group P1 with a = 5.9738（11）, b = 12.528（2）, c = 18.021（4） ?, α = 93.156（3）o, β =98.067（3）o, γ = 92.692（3）o, V = 1331.3（4） ?3, Z = 2, S = 1.069, F（000） = 702, R = 0.0277 and wR =0.0688（I > 2σ（I））. Complex 2 shows a two-dimensional network structure, which crystallizes in monoclinic system, space group C2/c with a = 13.6733（19）, b = 18.422（3）, c = 10.4307（15） ?, β =93.881（2）o, V= 2621.4（7） ?3, Z = 4, S = 1.110, F（000） = 1372, R = 0.0302 and wR = 0.0811（I >2σ（I））. The solid-state fluorescent test results show tcomplex 1 has weaker fluorescence intensity than the ligand. However, complex 2 has excellent fluorescence properties, and can emit bright red light under the irradiation of ultraviolet lamp.展开更多
The process for removal of samarium from NdCl_3 solution containing a little samarium by solvent extrac-tion with unsaponated Di (2-ethyl hexyl) orthosphoric acid (DEHPA) at acidic range is reported. The in-dustri...The process for removal of samarium from NdCl_3 solution containing a little samarium by solvent extrac-tion with unsaponated Di (2-ethyl hexyl) orthosphoric acid (DEHPA) at acidic range is reported. The in-dustrial experiments have been completed on a production line of 150 t Nd_2O_3 per annum in the Baotou ThirdRare Earth Factory. As a result of 9 step counter current extraction , Sm_2 O_3 content in Nd_2 O_3 drops down to0. 08 % from 0. 5% , the purity of neodymium oxide is over 99. 5% and the direct recovery of Nd_2O_3 is 92%～ 93% .展开更多
Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1， 1-dicyanoalkenes under mild conditions.
基金Project(51165032)supported by the National Natural Science Foundation of ChinaProject(20122BAB216017)supported by the Natural Science Foundation of Jiangxi Province,ChinaProject(2011-TW-03)supported by the Open Foundation of Jiangxi Key Laboratory for Advanced Copper and Tungsten Materials,China
文摘The effects of rare earth samarium （Sm） additions on the microstructure and mechanical properties of as-cast Al-Si-Cu alloy were investigated by optical microscopy and scanning electron microscopy （SEM）. The results show that Sm can effectively refine the a（Al） dendrite and the eutectic silicon. In addition, the shape of iron-rich phases changes from the Chinese script-like to slender-like ones and the volume fraction of iron-rich phases is decreased by the addition of Sm. Two kinds of Sm-rich interrnetallics are found： AlSiSm and AlSiCuSm. The plate-like AlSiCuSm phase always associates with the needle-like AISiSm phase. The mechanical properties are improved by the addition of Sm, and the good ultimate tensile strength （220 MPa） and elongation （3. 1%） are obtained from the Al-Si-Cu-1.0Sin alloy.
文摘Trivalent samarium ion (Sm^(3+)) activated calcium molybdate (CaMoO_4) phosphor was prepared by solid-state reaction in air. The XRD pattern of the powder CaMoO_4∶Sm shows that the CaMoO_4∶Sm single phase is developed fully through our preparation procedure. The excitation spectrum of CaMoO_4∶Sm is composed of a broad absorption of host and some sharp lines of the f-f transition absorption of Sm^(3+). Illustrated in photoluminescence spectrum, CaMoO_4 doped with Sm^(3+) displays orange red emission that is ascribed to the inner 4f^5 electron transitions ~6H_(7/2)(orange)and ~6H_(9/2)(red)of Sm^(3+). Different from the sites of Sm^(3+) in CdWO_4, the Sm^(3+) ions substitute for the Ca^(2+) and form only one type emission center in the CaMoO_4 crystal lattice.
文摘Nanometer crystal samarium borate with a particle size of 20～40?nm was prepared using replacing solvent drying technique. The wear resistance and load carrying capacity of 500SN base oil could be improved and the friction coefficient could be decreased by the addition of nanometer samarium borate. But the dosage of samarium borate nanoparticles had to be controlled at a relatively low level, a higher concentration of nanoparticles was not of beneficial to the tribological performance of the oil. The optimal dosage of nanometer samarium borate is 1.0%. Tribochemical reactions took place in the tribological process, which resulted in the formation of deposition products including diboron trioxide and disamarium trioxide. Fe 2B and FeB were also found on the wear scar. The improvement of tribological properties of the oil comes from the formation of deposition layer and permeating layer. [
基金Project supported in part by the Key Project of Chinese Ministry of Education (205065) the Natural Science Foundation nf Zhejiang Province (Y405043)
文摘Spraque-Dawley(SD)big rats with weaning weight of (195±15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drank de-ionized water served as control and also used for analysis with the background. The other three groups were cultured for five months by drinking de-ionized water with 3.0, 4.5 and 6.0 mg·L-1 Sm (NO3)3, respectively. Compared with the rats in control, it is found that the organs of the treated rats are apparently pathologically changed, such as liver swell, lung intumescence, peritoneum conglutination and hardness. Especially, in the high Sm group, the pathological percentage in liver and lung is up to 30% . The pathological changes in liver and lung show that rare earth Sm does hazard biological effects to animals. With increasing Sm concentration, the weight rate of organ/body has a tendency of increasing; the activity of superoxide dismutase (SOD) in liver and kidney decreases, but the maglonydiadehyde (MDA) concentration increases, indicating the abilities of anti-oxidation and the lipid per-oxi-dation inhibition degenerate, which leads to hard pathological changes in organs. Moreover, the relative weight rate of organ/body, the activity of SOD and the MDA concentration are remarkably lager in liver than in kidney and other organs, suggesting that the biological effect of Sm on liver is the greatest and Sm has a high affinity for liver.
文摘The polymerization of acrylonitrile initiated by organolanthanide complexes alone is studied for the first time. The effect of polymerization conditions on catalytic activity of the title complex and molecular weight of the polymers produced have been studied.
基金financially supported by the Aeronautical Science Foundation of China(No.2012ZF53080)the Shaanxi Province Science and Technology Research and Development Program of China(No.2013K08-11)+1 种基金the Fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University(No.SKLSP201009)the 111 Project of China(No.B08040)
文摘The mechanical properties of Al-Cu-Mn casting alloy mainly depend on the morphology, distribution, size, and number ofθ′（Al2Cu） precipitates. In this study, we have analyzed the effect of rare earth samarium （Sm） addition on the kinetics of precipitation in the Al-Cu-Mn casting alloy by using differential scanning calorimetry （DSC） and high-resolution transmission electron microscopy. Thermal ef-fect peaks that are attributed to the formation and the dissolution of Guinier-Preston （GP） zone andθ′phase were identified from the DSC curves. The activation energy ofθ′formation was calculated by using both the Kissinger method and the analytical model, and the corre-sponding results were compared. Results suggest that the activation energy ofθ′formation in Al-Cu-Mn alloy is dramatically higher than that in Al-Cu-Mn-Sm alloy. Accordingly, it is concluded that the addition of rare earth Sm decreases the activation energy ofθ′formation and promotes the formation ofθ′precipitates.
基金financially supported by the Natural Science Foundation of Jiangsu Province (No.BK2007724)Military Coordination Scientific Research Projects (No.JPPT-1486)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions (No.CXZZ110333)A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘A novel 1064 tun laser stealth absorbent of SmzO2S was prepared by flux method. The effects of different calcining temperatures and fluxes on the reflective property of Sm2O2S were investigated. The phase composition, morphology, and reflectivity of the powders were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and ultraviolet-visible spectrophotometer （UVPC）. The results showed that pure phase of Sm202S could be obtained with Na2CO3 as flux above 950~C, and the reflectivity decreased with the calcination temperature increasing. Compared with other samarium compounds, the reflectivity at 1064 nm of Sm2O2S was the lowest. Different fluxes had great impact on the phase composition, particle morphology, and reflectivity of the products. In short, Sm2O2S was suitable as a kind of absorbent against 1064 nm laser.
基金Project supported by the Hunan Provincial Natural Sciences Foundation of China (03JJY3019)
文摘The coordination complex Sm（C7H5O2）2·（C9H6NO）, synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline, was characterized with IR, elemental analysis, molar conductance, and thermogravimatric analysis. The standard molar enthalpies of solution of [ SmCl3·6H2O （s） ], [ 2C7H6O3 （s） ], [ C9H7NO （ s ） ] and [ Sm （C7H5O3） 2·（ C9H6NO ） （ s ） ] in the calorimetric solvent were determined with the solution-reaction isoperibol calorimeter at 298.15 K to be △sHm^- [ SmCl3·6H2O （s）, 298.15 K ] = - 103.98 ± 0.04 kJ·mol^-1, △sHm^- [2 C7H6O3 （s）, 298.15 K] = 16.35±0.14 kJ·mol^-1,△sHm^-[C9H7NO （s）, 298.15 K] = -6.11±0.08 kJ·mol^-1 and △sHm^-[Sm（C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 130.08 ± 0.04 kJ·mol^-1, respectively. The enthalpy was determined to be △rHm^- = 89.59 ±0.18 kJ·mol^-1 for the reaction SmCl3·6H2O（s） ＋ 2C7H6O3（s） ＋ C9H7NO（s） = Sm （C7H5O3） 2·（C9H6NO） （ s ） ＋ 3HCl （g） ＋ 6H2O （ l ）. According to the above results and the data given in literature and through Hess＇ law, the standard molar enthalpy of formation of Sin（ C7H5O3 ）2·（C9H7NO）（s） was estimated to be △rHm^- [ Sm （C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 2055.9 ± 3.03 kJ·mol^-1.
文摘The intermolecular reductive coupling of nitrites with azobenzene induced by SmI2 was studied. Amidine derivatives were prepared in good yields under neutral and mild conditions.
基金Supported by the National Natural Science Fundation of China
文摘The present paper contains the reaction mechanism of the rare earth complex with 2-(2-arsenophenylazo)-7-(2, 6-dichloro-4-fluoro-phenylazo)- 1, 8-dihydroxynaphthalene-3, 6-disulfonic acid (DCF-arsenazo) studied preliminarily with a fully automated stopped-flow analyzer. A method with a high sensitivity and selectivity is proposed for the simultaneous determination of samarium and gadolinium based on the differential kinetic reaction of the rare earth complex with DCF-arsenazo. Sm and Gd in their concentrated oxides were determined with the relative errors less than 6%.
文摘The reduction of disulfides by samarium diiodide led to sa arium thiolates (ArSSml2).This new thiolate anion species reacted smoothly with α, β -unsaturated esters (nitriles) to give 1,4-addition products β -thioesters and β -thionitriles in good yields under mild and neutralcondition.
基金supported by NSFC(U1504531)University Key Scientific Research Project of Henan Province(19B150014)
文摘Two crystals, [Sm（Hcpna）（cpna）·3 H2O]n（1） and [Eu（Hcpna）（cpna）·2 H2O]n（2）,have been synthesized by solvothermal method based on Sm3+ and Eu3+ with multiple acid ligands5-（4-carboxyphenoxy）nicotinic acid（H2cpna）, and the new complexes have been characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, thermogravimetric analysis and fluorescence analysis. Complex 1 exhibits a 1 D chain structure. It crystallizes in the triclinic system, space group P1 with a = 5.9738（11）, b = 12.528（2）, c = 18.021（4） ?, α = 93.156（3）o, β =98.067（3）o, γ = 92.692（3）o, V = 1331.3（4） ?3, Z = 2, S = 1.069, F（000） = 702, R = 0.0277 and wR =0.0688（I > 2σ（I））. Complex 2 shows a two-dimensional network structure, which crystallizes in monoclinic system, space group C2/c with a = 13.6733（19）, b = 18.422（3）, c = 10.4307（15） ?, β =93.881（2）o, V= 2621.4（7） ?3, Z = 4, S = 1.110, F（000） = 1372, R = 0.0302 and wR = 0.0811（I >2σ（I））. The solid-state fluorescent test results show tcomplex 1 has weaker fluorescence intensity than the ligand. However, complex 2 has excellent fluorescence properties, and can emit bright red light under the irradiation of ultraviolet lamp.
文摘The process for removal of samarium from NdCl_3 solution containing a little samarium by solvent extrac-tion with unsaponated Di (2-ethyl hexyl) orthosphoric acid (DEHPA) at acidic range is reported. The in-dustrial experiments have been completed on a production line of 150 t Nd_2O_3 per annum in the Baotou ThirdRare Earth Factory. As a result of 9 step counter current extraction , Sm_2 O_3 content in Nd_2 O_3 drops down to0. 08 % from 0. 5% , the purity of neodymium oxide is over 99. 5% and the direct recovery of Nd_2O_3 is 92%～ 93% .
基金Preject (No. 20072033) supported by the National Natural Science Foundation of China and Zhejiang Provincial Natural Science Foundation of China
文摘Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1， 1-dicyanoalkenes under mild conditions.
