Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial ...Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial oxygen in Ln(SiW9)2 was coordinated with Ln3- , where Ln-3 was in the inner side of the heteropoly anions, while the fundamental structure of SiW9 had little change. The result was supported by ion exchange experiment.展开更多
Heteropoly-complexes K17[Ln(CuW11O39)2].xH2O(Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Dy) were prepared. The properties of the products were investigated by ion-exchange, conductometric titration, IR, UV and X-ray powder diff...Heteropoly-complexes K17[Ln(CuW11O39)2].xH2O(Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Dy) were prepared. The properties of the products were investigated by ion-exchange, conductometric titration, IR, UV and X-ray powder diffraction. The results show that the structure of the products is similar to that of U(a-Ge11O39)2 and consistent with the model proposed by Peacock.展开更多
Eleven heteropolytungstophosphate compounds with lanthanon having Dawson structure were prepared, Ln_2[P_2W_(18)O_(62)]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Yb).Their structures were studied by IR,UV,polarograp...Eleven heteropolytungstophosphate compounds with lanthanon having Dawson structure were prepared, Ln_2[P_2W_(18)O_(62)]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Yb).Their structures were studied by IR,UV,polarography ,X-ray diffraction and X-ray photoelectron spectroscopy.展开更多
The titled complex has been synthesized by the reaction of sodium sulfo-salicylate with lanthanum and yttrium perchlorate. The crystal structure has been determined by single crystal X-ray diffractometry. The crystal ...The titled complex has been synthesized by the reaction of sodium sulfo-salicylate with lanthanum and yttrium perchlorate. The crystal structure has been determined by single crystal X-ray diffractometry. The crystal is monoclinic with space group C2/c. The unit cell parameters are as follows: a=16.289(8), b=18.323(8), c=22.044(8) A, β=106.34(2)°, V=6314(6) A3, Z=4 and Dc=1.764 g/cm3. The structure was solved by direct method. The least-square refinement based on 3776 observed reflections [F > 6σ(F)] converged to a final R=8.6% and F(000) is 3548. Yttrium ion with eight-coordinate is located in central of the molecule, the two lanthanum ions with ten-coordinate are located at the two sides of yttrium ion. There are two positions for Na in the molecule, one is in the C2 axis with six coordinate, the other one is in a general position with five-coordinate.展开更多
A new family of isostructural 3 d-4 f polymetallic complexes,formulated as [Cu_(6)Ln_(5)(μ_(3)OH)_(9)(C_(4)H_(8)O_(2)N)_(6)(C_(5)H_(4)ON)_(6)(H_(2)O)_(9)]·(ClO_(4))_(6)·(H_(2)O)_(22)(Ln=Pr,1;Nd,2;Sm,3;Eu,4;...A new family of isostructural 3 d-4 f polymetallic complexes,formulated as [Cu_(6)Ln_(5)(μ_(3)OH)_(9)(C_(4)H_(8)O_(2)N)_(6)(C_(5)H_(4)ON)_(6)(H_(2)O)_(9)]·(ClO_(4))_(6)·(H_(2)O)_(22)(Ln=Pr,1;Nd,2;Sm,3;Eu,4;Gd,5),was successfully isolated through the simple hydrolysis reaction of 2-aminoisobutyric acid,2-hydroxypyridine,Cu(CH_(3)COO)_(2)·H_(2)O,and Ln(ClO_(4))_(3)·6 H_(2)O.Notably,the [Cu_(6)Ln_(5)] clusters with high molecular symmetry of D_(3h) are rare examples of2-aminoisobutyric acid-based 3 d-4 f clusters.The successful theoretical modeling of 5 yielded that the Gd-Gd exchange is of order 0.2 K,whereas the Gd-Cu exchange is an order of magnitude larger.Magnetization data collected for comp lex 5 yield a magnetic entropy change(-ΔSm) of 19.6 J kg^(-1) K^(-1)<1 at 3 K and 7 T,which may be attributed to the weak magnetic interactions between the component metal ions.展开更多
The aim of the present investigation was to study the potential of two brown seaweeds(Sargassum wightii and Turbinaria conoides) to remove praseodymium ions from solutions. Due to swelling problems, the seaweed biom...The aim of the present investigation was to study the potential of two brown seaweeds(Sargassum wightii and Turbinaria conoides) to remove praseodymium ions from solutions. Due to swelling problems, the seaweed biomasses were also immobilized using polysulfone matrices which amplified hydraulic conductivity more than 7.1 times. At optimum pH of 5, maximum Pr(III) uptakes of 131.4, 146.4, 111.2 and 119.5 mg/g were observed for free-S. wightii, free-T. conoides, polysulfone immobilized S. wightii(PISW) and polysulfone immobilized T. conoides(PITC), respectively. Experimental biosorption isotherms were successfully described using the Langmuir, Freundlich and Sips model. Owing to intraparticle diffusion, rate of Pr(III) sorption by immobilized biosorbents was slow and equilibrium attainment took 240 min compared to only 90 min by free biomasses. However, regeneration of seaweed biomasses for repeated sorption application was only possible with immobilization biosorbents. With 0.1 mol/L HCl as elutant, both PITC and PISW exhibited invariable Pr(III) uptake capacity and very high mechanical stability over 10 sorption-desorption cycles.展开更多
文摘Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial oxygen in Ln(SiW9)2 was coordinated with Ln3- , where Ln-3 was in the inner side of the heteropoly anions, while the fundamental structure of SiW9 had little change. The result was supported by ion exchange experiment.
基金Supported by the National Natural Science Foundation of China.
文摘Heteropoly-complexes K17[Ln(CuW11O39)2].xH2O(Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Dy) were prepared. The properties of the products were investigated by ion-exchange, conductometric titration, IR, UV and X-ray powder diffraction. The results show that the structure of the products is similar to that of U(a-Ge11O39)2 and consistent with the model proposed by Peacock.
文摘Eleven heteropolytungstophosphate compounds with lanthanon having Dawson structure were prepared, Ln_2[P_2W_(18)O_(62)]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Yb).Their structures were studied by IR,UV,polarography ,X-ray diffraction and X-ray photoelectron spectroscopy.
基金supported by the National Natural Science Foundation of China and Laboratory of Rare Earth Chemistry and Physics,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences.
文摘The titled complex has been synthesized by the reaction of sodium sulfo-salicylate with lanthanum and yttrium perchlorate. The crystal structure has been determined by single crystal X-ray diffractometry. The crystal is monoclinic with space group C2/c. The unit cell parameters are as follows: a=16.289(8), b=18.323(8), c=22.044(8) A, β=106.34(2)°, V=6314(6) A3, Z=4 and Dc=1.764 g/cm3. The structure was solved by direct method. The least-square refinement based on 3776 observed reflections [F > 6σ(F)] converged to a final R=8.6% and F(000) is 3548. Yttrium ion with eight-coordinate is located in central of the molecule, the two lanthanum ions with ten-coordinate are located at the two sides of yttrium ion. There are two positions for Na in the molecule, one is in the C2 axis with six coordinate, the other one is in a general position with five-coordinate.
基金supported by Shenzhen Science and Technology Program (No.JCYJ20180306170859634)National Natural Science Foundation of China (Nos.21773130,21801202,21871219, 21971203 and 21620102002)+4 种基金Shaanxi National Science Foundation (No.2019JQ-016)China Postdoctoral Science Foundation (Nos. 2019T120891 and 2018M643615)Key Laboratory Construction Program of Xi’an Municipal Bureau of Science and Technology (No. 201805056ZD7CG40)Cyrus Chung Ying Tang Foundation and Fundamental Research Funds for Central Universitiessupported by the Deutsche Forschungsgemeinschaft DFG (Nos.314331397,SCHN 615/23-1)。
文摘A new family of isostructural 3 d-4 f polymetallic complexes,formulated as [Cu_(6)Ln_(5)(μ_(3)OH)_(9)(C_(4)H_(8)O_(2)N)_(6)(C_(5)H_(4)ON)_(6)(H_(2)O)_(9)]·(ClO_(4))_(6)·(H_(2)O)_(22)(Ln=Pr,1;Nd,2;Sm,3;Eu,4;Gd,5),was successfully isolated through the simple hydrolysis reaction of 2-aminoisobutyric acid,2-hydroxypyridine,Cu(CH_(3)COO)_(2)·H_(2)O,and Ln(ClO_(4))_(3)·6 H_(2)O.Notably,the [Cu_(6)Ln_(5)] clusters with high molecular symmetry of D_(3h) are rare examples of2-aminoisobutyric acid-based 3 d-4 f clusters.The successful theoretical modeling of 5 yielded that the Gd-Gd exchange is of order 0.2 K,whereas the Gd-Cu exchange is an order of magnitude larger.Magnetization data collected for comp lex 5 yield a magnetic entropy change(-ΔSm) of 19.6 J kg^(-1) K^(-1)<1 at 3 K and 7 T,which may be attributed to the weak magnetic interactions between the component metal ions.
基金supported by Ramalingaswami Re-entry Fellowship from Department of Biotechnology,Ministry of India,India
文摘The aim of the present investigation was to study the potential of two brown seaweeds(Sargassum wightii and Turbinaria conoides) to remove praseodymium ions from solutions. Due to swelling problems, the seaweed biomasses were also immobilized using polysulfone matrices which amplified hydraulic conductivity more than 7.1 times. At optimum pH of 5, maximum Pr(III) uptakes of 131.4, 146.4, 111.2 and 119.5 mg/g were observed for free-S. wightii, free-T. conoides, polysulfone immobilized S. wightii(PISW) and polysulfone immobilized T. conoides(PITC), respectively. Experimental biosorption isotherms were successfully described using the Langmuir, Freundlich and Sips model. Owing to intraparticle diffusion, rate of Pr(III) sorption by immobilized biosorbents was slow and equilibrium attainment took 240 min compared to only 90 min by free biomasses. However, regeneration of seaweed biomasses for repeated sorption application was only possible with immobilization biosorbents. With 0.1 mol/L HCl as elutant, both PITC and PISW exhibited invariable Pr(III) uptake capacity and very high mechanical stability over 10 sorption-desorption cycles.