Solvent extraction has been the most widely used technique for rare earths separation. In this study, thermodynamics and kinetics of lutetium extraction with HEH（EHP） in hydrochloric acid medium were investigated. T...Solvent extraction has been the most widely used technique for rare earths separation. In this study, thermodynamics and kinetics of lutetium extraction with HEH（EHP） in hydrochloric acid medium were investigated. The extraction mechanism and the relevant parameters were determined by experiment research which can guide the practical extraction process. The data indicated that chloride ion had no effect on lutetium extraction, the rate constant increased when stirring speed was enhanced. Effects of temperature, HEH（EHP） concentration, acidity, and chloride concentration were also studied. Thickness of the diffusion film was also calculated to be 4.66×10^（-3） cm at 150 r/min.展开更多
Low-lying electronic states of the lutetium dimer （Lu2） were studied based on density functional theory （DFT） using ten different density functionals together with three different relativistic effective core pseud...Low-lying electronic states of the lutetium dimer （Lu2） were studied based on density functional theory （DFT） using ten different density functionals together with three different relativistic effective core pseudopotentials （RECPs）. Relative state energies, equilibrium bond lengths, vibrational frequencies, and ground-state dissociation energies were evaluated. It was found that the ground state is a triplet state irrespective of the type of functional and RECP used. This result is in contrast with a previous DFT calculation which gave a singlet ground state for Lu2. By comparing with the high-level ab initio and available experimental results, it is evident that the hybrid-GGA functionals combined with the Stuttgart smallcore RECP yield the best overall agreement for the properties under study. The effects of Hartree-Fock exchange in B3LYP functional on the calculated bond length and dissociation energy of the ground state were examined, and rationalized in terms of 5d participation in Lu-Lu covalent bonding.展开更多
The title complex was synthesized in an aqueous solution and its crystal structure was determined by X-raydiffraction method. It crystalizes in triclinic crystal system, space group P1, formula C36H110N8O55Lu4, Mr=223...The title complex was synthesized in an aqueous solution and its crystal structure was determined by X-raydiffraction method. It crystalizes in triclinic crystal system, space group P1, formula C36H110N8O55Lu4, Mr=2235.2,a=1.09787(7) nm, b=1.27603(10) nm, c=1.45903(10) nm; α=75.769(6)°, β=85.288(5)°, γ=71.577(6)°, V=1.8797(2) nm3,Z=1, Dc= 1.975 g·cm-3, F(000)=1106, μ=5.312 mm-1; R1=0.0239, wR2=0.0527 for 7156 reflections with I>2σ (I). In the complex, the lutetium ion is coordinated by two nitrogen atoms andsix oxygen atoms and the coordination number is 8. Its coordination polyhedron can be described as a distorted squareantiprism. The complex is of an infinite chain structure. The complex was characterized by elemental analysis, IR spectra and thermal analysis.展开更多
This paper reports on the selective transport of Lu(Ⅲ)from La(III)and Sm(III)through a polymer inclusion membrane(PIM)composed of 40 wt%di(2-ethylhexyl)phosphinic acid(P227)and 60 wt%poly(vinylidene fluoride)(PVDF).B...This paper reports on the selective transport of Lu(Ⅲ)from La(III)and Sm(III)through a polymer inclusion membrane(PIM)composed of 40 wt%di(2-ethylhexyl)phosphinic acid(P227)and 60 wt%poly(vinylidene fluoride)(PVDF).Basically,the changes in surface morphology,thickness and water contact angle of this PVDF-based PIM containing P227(P227@PVDF PIM)with different polymer concentrations were investigated.By solvent extraction experiments,it is found that Lu(Ⅲ)can be selectively extracted from La(Ⅲ)and Sm(Ⅲ)at pH 1.5 in hydrochloric acid solution.According to this result,P227@PVDF PIM was used to selectively transport Lu(Ⅲ)from hydrochloric acid feed solution containing similar concentration of La(Ⅲ)and Sm(Ⅲ).The recovery factor of Lu(III)is 91% after 36 h,and about 5%of Sm(Ⅲ)was also transported through the PIM.The concentration of La(III)in the feed solution and the stripping solution does not change.Furthermore,to overcome the ubiquitous decline of transport efficiency caused by the loss of carrier or the damage of membrane structure after long-term use of PIMs,a process for regenerating PIMs was first proposed and implemented.By comparison of the regenerated PIM with the normal PIM,there is almost no difference in the SEM image,ATR-FTIR spectrum and Lu(III)transport efficiency.It is expected that P227@PVDF PIMs have the potential to be applied to the grouped separation of rare earth elements(REEs),and this study also can be as an inspiration for the further study on the PIMs regeneration process.展开更多
β-Imidophosphonamido ligated lutetium alkyl complex（NPNDipp）Lu（CH2Si Me3）2（THF）（NPNDipp = Ph2P（NC6H3iPr2-2,6）2） with the activation of AliBu3 and [Ph3C][B（C6F5）4] exhibited high catalytic activity, medium...β-Imidophosphonamido ligated lutetium alkyl complex（NPNDipp）Lu（CH2Si Me3）2（THF）（NPNDipp = Ph2P（NC6H3iPr2-2,6）2） with the activation of AliBu3 and [Ph3C][B（C6F5）4] exhibited high catalytic activity, medium syndio-（rr = 66%） but remarkably high 3,4-regioselectivity for the polymerization of β-myrcene（MY）. In sharp contrast, high isotactic 3,4-polymyrcene（PMY）（mm = 95%） was obtained by the precursor（NPN^Et）Lu（CH2Si Me3）2（THF）（NPN^Et = PPh2（NC6H3^iPr2-2,6）（NC6H4-Et-2）） with less bulky substituents on the N-aryl ring.展开更多
Lutetium β-tricalcium phosphate Ca9Lu（PO4）7 was synthesized by solid-state reaction at 1200 ℃, and investigated by means of a combination of scanning electron microscopy （SEM） equipped with energy dispersive X-r...Lutetium β-tricalcium phosphate Ca9Lu（PO4）7 was synthesized by solid-state reaction at 1200 ℃, and investigated by means of a combination of scanning electron microscopy （SEM） equipped with energy dispersive X-ray spectroscopy （EDS）, X-ray diffraction （XRD）, Fourier transform infrared （FTIR） and Raman spectroscopies. SEM morphological analysis reveals the presence of sub spherical and prismatic micro crystalline aggregates, while EDS semi-quantitative analysis confirms the nominal Lu/Ca compo- sition. The unit cell and the space group were determined by X-ray powder diffraction data showing that the compound crystallizes in the rhombohedral R3c wfiitlockite-type structure, with unit cell constants a - b 1.04164（1） nm, c 3.7302（1） nm and cell volume V 3.5051（1） nm^3. The investigation was completed with the structural refinement by the Rietveld method, and discussion of the distribution of Lu within cationic sites according to the results of the Rietveld refinement. The FIIR and Raman spectra, correlated to isostructural rare earth phosphates from literature, show slight band shifts of the phosphate modes correlated to the evolving size of the rare earth elements.展开更多
The extraction and stripping of scandium from its sulfate solutions by isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester (PT-2, HL) diluted with n-hexane are reported. A high efficiency of separation betwee...The extraction and stripping of scandium from its sulfate solutions by isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester (PT-2, HL) diluted with n-hexane are reported. A high efficiency of separation between scandium, iron and lutetium can be achieved by controlling aqueous acidity. Different mechanisms of Sc3+ with PT-2 in various acid range have been proposed.At lower aqueous acidity, it is a cation exchange reaction, while at higher acidity. a solvation reaction was ascertained. Its IR and NMR spectra have been discussed. The effect of temperature on extraction of Sc3+ was observed and thermodynamic functions were calculated.展开更多
The adsorption behavior and mechanism of a novel chelate resin, iminodiacetic acid resin (IDAAR) for Lu(Ⅲ) were investigated. The statically saturated adsorption capacity is 210.8 mg·g^(-1) at 298 K in HAc-NaAc ...The adsorption behavior and mechanism of a novel chelate resin, iminodiacetic acid resin (IDAAR) for Lu(Ⅲ) were investigated. The statically saturated adsorption capacity is 210.8 mg·g^(-1) at 298 K in HAc-NaAc medium. The Lu(Ⅲ) adsorbed on IDAAR can be eluted by 0.5 mol·L^(-1) HCl and the elution percentage reaches 96.5%. The resin can be regenerated and reused without obvious decrease in adsorption capacity. The apparent adsorption rate constant is k_(298)=2.0×10^(-5) s^(-1). The adsorption behavior of IDAAR for Lu(Ⅲ) obeys the Freundlich isotherm. The thermodynamic adsorption parameters, enthalpy change ΔH, free energy change ΔG and entropy change ΔS of IDAAR for Lu(Ⅲ) are 13.1 kJ·mol^(-1), -1.37 kJ·mol^(-1) and 48.4 J·mol^(-1)·K^(-1), respectively. The apparent activation energy is E_a=31.3 kJ·mol^(-1). The molar coordination ratio of the functional group of IDAAR to Lu(Ⅲ) is about 3∶1. The adsorption mechanism of IDAAR for Lu(Ⅲ) was examined by chemical method and IR spectrometry.展开更多
Electron affinities (EAs) of most lanthanide elements still remain unknown due to their relatively low EA values. In the present work, the cryogenically controlled ion trap is used for accumulating atomic lutetium ani...Electron affinities (EAs) of most lanthanide elements still remain unknown due to their relatively low EA values. In the present work, the cryogenically controlled ion trap is used for accumulating atomic lutetium anion Lu^-, which makes the measurement of electron affinity of lutetium become practicable. The high-resolution photoelectron spectra of Lu^- are obtained via the slow-electron velocity-map imaging method. The electron affinity of Lu is determined to be 1926.2(50) cm^-1 or 0.23882(62) eV. In addition, two excited states of Lu^- are observed.展开更多
This study was done to quality assure the Hawkeye SPECT/CT at the St. Olav’s hospital and create a clinical method for doing individual dosimetry with <sup>177</sup>Lu-octreotate in targeted radionuclide ...This study was done to quality assure the Hawkeye SPECT/CT at the St. Olav’s hospital and create a clinical method for doing individual dosimetry with <sup>177</sup>Lu-octreotate in targeted radionuclide therapy for neuroendocrine tumors. Various quality control parameters were performed on Infinia Hawkeye SPECT/CT. A calibration dose of 160% ± 2% MBq was ordered and first calibrated for all the dose calibrators. The uniformity test was obtained using a 40 MBq Tc-99m point source positioned 2.5 m away from the two detectors. A 200 MBq Tc-99m was diluted in 70 ml of water, dispersed in six syringes for the registration test. A Lu-177 point source was placed in front of the detectors, one at a time, to check the energy peaks. The Jaczczak phantom with a hollow sphere set (volumes: 0.5, 1, 2, 4, 8, and 16) ml with an additional 60 ml sphere was used for the 3D sensitivity and recovery with Lu-177. Total activity of 945.3 MBq was added to 160 ml of water yielding an activity concentration of 5.908 MBq/ml in the spheres. The phantom was then scanned at various time intervals. A cylindrical phantom with a volume of 6283 ml was also used to obtain the cross-calibration measurement (cps/MBq). Total activity of 995.6 MBq was added and the phantom was scanned at days 0, 6, 13 and 23. The dose calibration factor was changed from 762 to 760 to achieve correct doses. The 2D mean sensitivity factor was 5.56 cps/MBq. Uniformities for both detectors were approved after iteration calibration of the PM tubes. The X-ray to SPECT registration was found to be accurate and within specifications. The energy peak test revealed off-centered 208 keV energy peaks for the two detectors. Quality assurance of imaging devices using radiation is essential for radiation protection and ensures a high-quality image.展开更多
BACKGROUND Lutetium has been shown to be an important potential innovation in pre-treated metastatic castration-resistant prostate cancer.Two clinical trials have evaluated lutetium thus far(therap and vision with 99 ...BACKGROUND Lutetium has been shown to be an important potential innovation in pre-treated metastatic castration-resistant prostate cancer.Two clinical trials have evaluated lutetium thus far(therap and vision with 99 and 385 patients,respectively),but their results are discordant.AIM To synthetize the available evidence on the effectiveness of lutetium in pre-treated metastatic castration-resistant prostate cancer;and to test the application of a new artificial intelligence technique that synthetizes effectiveness based on reconstructed patient-level data.METHODS We employed a new artificial intelligence method(shiny method)to pool the survival data of these two trials and evaluate to what extent the lutetium cohorts differed from one another.The shiny technique employs an original reconstruction of individual patient data from the Kaplan-Meier curves.The progression-free survival graphs of the two lutetium cohorts were analyzed and compared.RESULTS The hazard ratio estimated was in favor of the vision trial;the difference was statistically significant(P<0.001).These results indicate that further studies on lutetium are needed because the survival data of the two trials published thus far are conflicting.CONCLUSION Our study confirms the feasibility of reconstructing patient-level data from survival graphs in order to generate a survival statistics.展开更多
This article presents a case of a patient with relapsed esthesioneuroblastoma (ENB), an aggressive rare tumor that arises from the specialized sensory epithelial olfactory cells in the skull base area, which was initi...This article presents a case of a patient with relapsed esthesioneuroblastoma (ENB), an aggressive rare tumor that arises from the specialized sensory epithelial olfactory cells in the skull base area, which was initially treated with endoscopic surgery, followed by adjuvant radiotherapy. After local relapse, new surgical approaches and subsequent lines of platin-based chemotherapy were performed. A PET-CT with <sup>68</sup>GALIUM DOTATATOC (PET-DOTATOC) showed intense uptake of disease, compatible with the presence of somatostatin receptors, in the face, nodes, liver, bones, and meningeal area. Treatment with 4 cycles of <sup>177</sup>Lutetium-Dotatate was performed, followed by maintenance octreotide, with a major radiological and clinical response that is lasting more than 1 year after treatment. This article describes a rare case of a skull-base tumor, with multiple recurrences, in which disease control was achieved with a targeted Peptide Receptor Radionuclide Therapy (PRRT) with <sup>177</sup>Lutetium-Dotatate, and discusses factors that could influence the incorporation of this form of therapy. Previous case reports proved the potential efficacy of this therapy usually given for low-grade neuroendocrine tumors and will be carefully reviewed.展开更多
The cross-sections for the 175Lu(n,p)175Yb,175Lu(n,α)172Tm,176Lu(n,α)173Tm,175Lu(n,2n)174mLu,and 175Lu(n,2n)174gLu reactions at 13.57,14.0314.62,and 14.86 MeV neutron energies were measured using an activation techn...The cross-sections for the 175Lu(n,p)175Yb,175Lu(n,α)172Tm,176Lu(n,α)173Tm,175Lu(n,2n)174mLu,and 175Lu(n,2n)174gLu reactions at 13.57,14.0314.62,and 14.86 MeV neutron energies were measured using an activation technique.The theoretical excitation functions of these reactions were calculated using the Talys-1.95 code.The reaction cross-section data experimentally obtained were analyzed and compared with experimental data reported in the literature,data from five major evaluated nuclear data libraries of IAEA,and theoretical values based on Talys-1.95.The data obtained at some neutron energies agree with some of the data reported in the literature and theoretical values based on Talys-1.95.The consistency of the theoretical curves of excitation functions based on Talys-1.95 with the data obtained in this study and those reported in the literature is higher than that of the evaluation curves of excitation functions for the 175Lu(n,p)175Yb,175Lu(n,α)172 Tm,and 176Lu(n,α)173Tm reactions.This study is helpful because it provides new evaluated reaction cross-section data on lutetium(which is a fusion reactor material),improves the quality of neutron-induced reaction cross section data libraries,and advances the research on related applications.展开更多
The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfu...The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating technique.The resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 K was observed at pressure of 218 GPa in the experiments.The Tcdecreased to 65 K when pressure was at 181 GPa.From the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 T.The in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors.展开更多
A novel sol-gel processing was developed to synthesize polycrystalline cerium-doped lutetium pyrosilicate （Lu2Si2O7Ce, LPS ：Ce） powders under low temperature. It was found that the addition of propylene oxide （PPO...A novel sol-gel processing was developed to synthesize polycrystalline cerium-doped lutetium pyrosilicate （Lu2Si2O7Ce, LPS ：Ce） powders under low temperature. It was found that the addition of propylene oxide （PPO） could promote the formation of Lu-O-Si bonds in precursor, which was beneficial to the formation of LPS phase. X-ray diffraction （XRD） patterns indicated that the single-phased LPS powder was well crystallized at 1050℃. Microstructure observation demonstrated that the synthetic LPS powder was composed of ellipsoidal grains with the mean size of 40 nm. The luminescent properties were characterized by photoluminescence （PL）, X-ray excited luminescence （XEL） and vacuum ultraviolet （VUV） spectroscopy at room temperature. The synthetic LPS：Ce powder emitted a broad emission spectrum centered at about 380 nm, which should be ascribed to the 5d→4f transition of Ce3＋. Decay time of the synthetic LPS：Ce powder was measured to be only 32 ns.展开更多
By applying pressures up to 42 GPa on the nitrogen-doped lutetium hydride(LuH2_(±x)N_(y)),we have found a gradual change of color from dark-blue to pink-violet in the pressure region of about 12 to 21 GPa.The tem...By applying pressures up to 42 GPa on the nitrogen-doped lutetium hydride(LuH2_(±x)N_(y)),we have found a gradual change of color from dark-blue to pink-violet in the pressure region of about 12 to 21 GPa.The temperature dependence of resistivity under pressures up to 50.5 GPa shows progressively optimized metallic behavior with pressure.Interestingly,in the pressure region for the color change,a clear decrease of resistivity is observed with the increase of pressure,which is accompanied by a clear increase of the residual resistivity ratio(RRR).Fitting to the low temperature resistivity gives exponents of about 2,suggesting a Fermi-liquid behavior in the low temperature region.The general behavior in a wide temperature region suggests that the electron-phonon scattering is still the dominant one.The magnetoresistance up to 9 T in the state under a pressure of 50.5 GPa shows an almost negligible effect,which suggests that the electric conduction in the pink-violet state is dominated by a single band.It is highly desired to have theoretical efforts in understanding the evolution of color and resistivity in this interesting system.展开更多
Structural growth mechanism,energetics,and electronic properties of cationic,neutral,and anionic lutetium doped germanium cluster LuGen^((+/0/-))(n=6~19)were comprehensively studied by the ABCluster unbiased global se...Structural growth mechanism,energetics,and electronic properties of cationic,neutral,and anionic lutetium doped germanium cluster LuGen^((+/0/-))(n=6~19)were comprehensively studied by the ABCluster unbiased global search technique with a hybrid density functional theory approach.Compared to the experimental PES,the anion evolution of structure can be clearly defined as four-phase:from the adsorbed to the link structure,then to the half cage motif,and finally to the endohedral structure.The results revealed that the LuGe16-as Frank-Kasper structure with high symmetry of Td can greatly enhance the stabilities.Doped structures have shown thermodynamic stability and appropriate energy gap.These materials are suitable semiconductors.Various approaches,including quasi-spherical geometry with closed-shell model,aromaticity,UV-Vis spectra,density of states(DOS)and partial density of states(PDOS)were applied to further support the results.展开更多
基金supported by National Natural Science Foundation of China(50934004)Beijing Nova Program
文摘Solvent extraction has been the most widely used technique for rare earths separation. In this study, thermodynamics and kinetics of lutetium extraction with HEH（EHP） in hydrochloric acid medium were investigated. The extraction mechanism and the relevant parameters were determined by experiment research which can guide the practical extraction process. The data indicated that chloride ion had no effect on lutetium extraction, the rate constant increased when stirring speed was enhanced. Effects of temperature, HEH（EHP） concentration, acidity, and chloride concentration were also studied. Thickness of the diffusion film was also calculated to be 4.66×10^（-3） cm at 150 r/min.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.10804001, No.10674002, and No.20773024）, the National High Technology Research and Development Program of China （863 Program） （No.2006AA09Z243-3）, and the Program for Innovative Research Team in Anhui Normal University of China.
文摘Low-lying electronic states of the lutetium dimer （Lu2） were studied based on density functional theory （DFT） using ten different density functionals together with three different relativistic effective core pseudopotentials （RECPs）. Relative state energies, equilibrium bond lengths, vibrational frequencies, and ground-state dissociation energies were evaluated. It was found that the ground state is a triplet state irrespective of the type of functional and RECP used. This result is in contrast with a previous DFT calculation which gave a singlet ground state for Lu2. By comparing with the high-level ab initio and available experimental results, it is evident that the hybrid-GGA functionals combined with the Stuttgart smallcore RECP yield the best overall agreement for the properties under study. The effects of Hartree-Fock exchange in B3LYP functional on the calculated bond length and dissociation energy of the ground state were examined, and rationalized in terms of 5d participation in Lu-Lu covalent bonding.
文摘The title complex was synthesized in an aqueous solution and its crystal structure was determined by X-raydiffraction method. It crystalizes in triclinic crystal system, space group P1, formula C36H110N8O55Lu4, Mr=2235.2,a=1.09787(7) nm, b=1.27603(10) nm, c=1.45903(10) nm; α=75.769(6)°, β=85.288(5)°, γ=71.577(6)°, V=1.8797(2) nm3,Z=1, Dc= 1.975 g·cm-3, F(000)=1106, μ=5.312 mm-1; R1=0.0239, wR2=0.0527 for 7156 reflections with I>2σ (I). In the complex, the lutetium ion is coordinated by two nitrogen atoms andsix oxygen atoms and the coordination number is 8. Its coordination polyhedron can be described as a distorted squareantiprism. The complex is of an infinite chain structure. The complex was characterized by elemental analysis, IR spectra and thermal analysis.
基金supported by the National Basic Research Program of China(2012CBA01202)the National Natural Science Foundation of China(51174184)the Key Research Program of the Chinese Academy of Sciences(KGZD-EW-201-1)。
文摘This paper reports on the selective transport of Lu(Ⅲ)from La(III)and Sm(III)through a polymer inclusion membrane(PIM)composed of 40 wt%di(2-ethylhexyl)phosphinic acid(P227)and 60 wt%poly(vinylidene fluoride)(PVDF).Basically,the changes in surface morphology,thickness and water contact angle of this PVDF-based PIM containing P227(P227@PVDF PIM)with different polymer concentrations were investigated.By solvent extraction experiments,it is found that Lu(Ⅲ)can be selectively extracted from La(Ⅲ)and Sm(Ⅲ)at pH 1.5 in hydrochloric acid solution.According to this result,P227@PVDF PIM was used to selectively transport Lu(Ⅲ)from hydrochloric acid feed solution containing similar concentration of La(Ⅲ)and Sm(Ⅲ).The recovery factor of Lu(III)is 91% after 36 h,and about 5%of Sm(Ⅲ)was also transported through the PIM.The concentration of La(III)in the feed solution and the stripping solution does not change.Furthermore,to overcome the ubiquitous decline of transport efficiency caused by the loss of carrier or the damage of membrane structure after long-term use of PIMs,a process for regenerating PIMs was first proposed and implemented.By comparison of the regenerated PIM with the normal PIM,there is almost no difference in the SEM image,ATR-FTIR spectrum and Lu(III)transport efficiency.It is expected that P227@PVDF PIMs have the potential to be applied to the grouped separation of rare earth elements(REEs),and this study also can be as an inspiration for the further study on the PIMs regeneration process.
基金financially supported by the National Natural Science Foundation of China(Nos.21104074 and 51321062)
文摘β-Imidophosphonamido ligated lutetium alkyl complex（NPNDipp）Lu（CH2Si Me3）2（THF）（NPNDipp = Ph2P（NC6H3iPr2-2,6）2） with the activation of AliBu3 and [Ph3C][B（C6F5）4] exhibited high catalytic activity, medium syndio-（rr = 66%） but remarkably high 3,4-regioselectivity for the polymerization of β-myrcene（MY）. In sharp contrast, high isotactic 3,4-polymyrcene（PMY）（mm = 95%） was obtained by the precursor（NPN^Et）Lu（CH2Si Me3）2（THF）（NPN^Et = PPh2（NC6H3^iPr2-2,6）（NC6H4-Et-2）） with less bulky substituents on the N-aryl ring.
基金Project partially supported by CNR(Italy)-CNRST(Morocco) Bilateral Project "Novel Ca_9RE(PO_4)_7 biomaterials:synthesis and multi-methodological characterization via X-ray techniques" reference CNR 1588/16
文摘Lutetium β-tricalcium phosphate Ca9Lu（PO4）7 was synthesized by solid-state reaction at 1200 ℃, and investigated by means of a combination of scanning electron microscopy （SEM） equipped with energy dispersive X-ray spectroscopy （EDS）, X-ray diffraction （XRD）, Fourier transform infrared （FTIR） and Raman spectroscopies. SEM morphological analysis reveals the presence of sub spherical and prismatic micro crystalline aggregates, while EDS semi-quantitative analysis confirms the nominal Lu/Ca compo- sition. The unit cell and the space group were determined by X-ray powder diffraction data showing that the compound crystallizes in the rhombohedral R3c wfiitlockite-type structure, with unit cell constants a - b 1.04164（1） nm, c 3.7302（1） nm and cell volume V 3.5051（1） nm^3. The investigation was completed with the structural refinement by the Rietveld method, and discussion of the distribution of Lu within cationic sites according to the results of the Rietveld refinement. The FIIR and Raman spectra, correlated to isostructural rare earth phosphates from literature, show slight band shifts of the phosphate modes correlated to the evolving size of the rare earth elements.
文摘The extraction and stripping of scandium from its sulfate solutions by isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester (PT-2, HL) diluted with n-hexane are reported. A high efficiency of separation between scandium, iron and lutetium can be achieved by controlling aqueous acidity. Different mechanisms of Sc3+ with PT-2 in various acid range have been proposed.At lower aqueous acidity, it is a cation exchange reaction, while at higher acidity. a solvation reaction was ascertained. Its IR and NMR spectra have been discussed. The effect of temperature on extraction of Sc3+ was observed and thermodynamic functions were calculated.
文摘The adsorption behavior and mechanism of a novel chelate resin, iminodiacetic acid resin (IDAAR) for Lu(Ⅲ) were investigated. The statically saturated adsorption capacity is 210.8 mg·g^(-1) at 298 K in HAc-NaAc medium. The Lu(Ⅲ) adsorbed on IDAAR can be eluted by 0.5 mol·L^(-1) HCl and the elution percentage reaches 96.5%. The resin can be regenerated and reused without obvious decrease in adsorption capacity. The apparent adsorption rate constant is k_(298)=2.0×10^(-5) s^(-1). The adsorption behavior of IDAAR for Lu(Ⅲ) obeys the Freundlich isotherm. The thermodynamic adsorption parameters, enthalpy change ΔH, free energy change ΔG and entropy change ΔS of IDAAR for Lu(Ⅲ) are 13.1 kJ·mol^(-1), -1.37 kJ·mol^(-1) and 48.4 J·mol^(-1)·K^(-1), respectively. The apparent activation energy is E_a=31.3 kJ·mol^(-1). The molar coordination ratio of the functional group of IDAAR to Lu(Ⅲ) is about 3∶1. The adsorption mechanism of IDAAR for Lu(Ⅲ) was examined by chemical method and IR spectrometry.
基金supported by the National Natural Science Foundation of China (No.91736102)the National Key R&D program of China (No.2018YFA0306504)
文摘Electron affinities (EAs) of most lanthanide elements still remain unknown due to their relatively low EA values. In the present work, the cryogenically controlled ion trap is used for accumulating atomic lutetium anion Lu^-, which makes the measurement of electron affinity of lutetium become practicable. The high-resolution photoelectron spectra of Lu^- are obtained via the slow-electron velocity-map imaging method. The electron affinity of Lu is determined to be 1926.2(50) cm^-1 or 0.23882(62) eV. In addition, two excited states of Lu^- are observed.
文摘This study was done to quality assure the Hawkeye SPECT/CT at the St. Olav’s hospital and create a clinical method for doing individual dosimetry with <sup>177</sup>Lu-octreotate in targeted radionuclide therapy for neuroendocrine tumors. Various quality control parameters were performed on Infinia Hawkeye SPECT/CT. A calibration dose of 160% ± 2% MBq was ordered and first calibrated for all the dose calibrators. The uniformity test was obtained using a 40 MBq Tc-99m point source positioned 2.5 m away from the two detectors. A 200 MBq Tc-99m was diluted in 70 ml of water, dispersed in six syringes for the registration test. A Lu-177 point source was placed in front of the detectors, one at a time, to check the energy peaks. The Jaczczak phantom with a hollow sphere set (volumes: 0.5, 1, 2, 4, 8, and 16) ml with an additional 60 ml sphere was used for the 3D sensitivity and recovery with Lu-177. Total activity of 945.3 MBq was added to 160 ml of water yielding an activity concentration of 5.908 MBq/ml in the spheres. The phantom was then scanned at various time intervals. A cylindrical phantom with a volume of 6283 ml was also used to obtain the cross-calibration measurement (cps/MBq). Total activity of 995.6 MBq was added and the phantom was scanned at days 0, 6, 13 and 23. The dose calibration factor was changed from 762 to 760 to achieve correct doses. The 2D mean sensitivity factor was 5.56 cps/MBq. Uniformities for both detectors were approved after iteration calibration of the PM tubes. The X-ray to SPECT registration was found to be accurate and within specifications. The energy peak test revealed off-centered 208 keV energy peaks for the two detectors. Quality assurance of imaging devices using radiation is essential for radiation protection and ensures a high-quality image.
文摘BACKGROUND Lutetium has been shown to be an important potential innovation in pre-treated metastatic castration-resistant prostate cancer.Two clinical trials have evaluated lutetium thus far(therap and vision with 99 and 385 patients,respectively),but their results are discordant.AIM To synthetize the available evidence on the effectiveness of lutetium in pre-treated metastatic castration-resistant prostate cancer;and to test the application of a new artificial intelligence technique that synthetizes effectiveness based on reconstructed patient-level data.METHODS We employed a new artificial intelligence method(shiny method)to pool the survival data of these two trials and evaluate to what extent the lutetium cohorts differed from one another.The shiny technique employs an original reconstruction of individual patient data from the Kaplan-Meier curves.The progression-free survival graphs of the two lutetium cohorts were analyzed and compared.RESULTS The hazard ratio estimated was in favor of the vision trial;the difference was statistically significant(P<0.001).These results indicate that further studies on lutetium are needed because the survival data of the two trials published thus far are conflicting.CONCLUSION Our study confirms the feasibility of reconstructing patient-level data from survival graphs in order to generate a survival statistics.
文摘This article presents a case of a patient with relapsed esthesioneuroblastoma (ENB), an aggressive rare tumor that arises from the specialized sensory epithelial olfactory cells in the skull base area, which was initially treated with endoscopic surgery, followed by adjuvant radiotherapy. After local relapse, new surgical approaches and subsequent lines of platin-based chemotherapy were performed. A PET-CT with <sup>68</sup>GALIUM DOTATATOC (PET-DOTATOC) showed intense uptake of disease, compatible with the presence of somatostatin receptors, in the face, nodes, liver, bones, and meningeal area. Treatment with 4 cycles of <sup>177</sup>Lutetium-Dotatate was performed, followed by maintenance octreotide, with a major radiological and clinical response that is lasting more than 1 year after treatment. This article describes a rare case of a skull-base tumor, with multiple recurrences, in which disease control was achieved with a targeted Peptide Receptor Radionuclide Therapy (PRRT) with <sup>177</sup>Lutetium-Dotatate, and discusses factors that could influence the incorporation of this form of therapy. Previous case reports proved the potential efficacy of this therapy usually given for low-grade neuroendocrine tumors and will be carefully reviewed.
基金Supported by the Natural Science Foundation of Henan(232300420130)National Natural Science Foundation of China(11575090)。
文摘The cross-sections for the 175Lu(n,p)175Yb,175Lu(n,α)172Tm,176Lu(n,α)173Tm,175Lu(n,2n)174mLu,and 175Lu(n,2n)174gLu reactions at 13.57,14.0314.62,and 14.86 MeV neutron energies were measured using an activation technique.The theoretical excitation functions of these reactions were calculated using the Talys-1.95 code.The reaction cross-section data experimentally obtained were analyzed and compared with experimental data reported in the literature,data from five major evaluated nuclear data libraries of IAEA,and theoretical values based on Talys-1.95.The data obtained at some neutron energies agree with some of the data reported in the literature and theoretical values based on Talys-1.95.The consistency of the theoretical curves of excitation functions based on Talys-1.95 with the data obtained in this study and those reported in the literature is higher than that of the evaluation curves of excitation functions for the 175Lu(n,p)175Yb,175Lu(n,α)172 Tm,and 176Lu(n,α)173Tm reactions.This study is helpful because it provides new evaluated reaction cross-section data on lutetium(which is a fusion reactor material),improves the quality of neutron-induced reaction cross section data libraries,and advances the research on related applications.
基金supported by the Natural Science Foundation of Chinathe National Key R&D Program of ChinaChinese Academy of Sciences through research projects(Grant Nos.2018YFA0305700,2021YFA1401-800,and XDB33010200)。
文摘The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating technique.The resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 K was observed at pressure of 218 GPa in the experiments.The Tcdecreased to 65 K when pressure was at 181 GPa.From the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 T.The in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors.
基金supported by the National Natural Science Foundation of China(Grant No.51172139)
文摘A novel sol-gel processing was developed to synthesize polycrystalline cerium-doped lutetium pyrosilicate （Lu2Si2O7Ce, LPS ：Ce） powders under low temperature. It was found that the addition of propylene oxide （PPO） could promote the formation of Lu-O-Si bonds in precursor, which was beneficial to the formation of LPS phase. X-ray diffraction （XRD） patterns indicated that the single-phased LPS powder was well crystallized at 1050℃. Microstructure observation demonstrated that the synthetic LPS powder was composed of ellipsoidal grains with the mean size of 40 nm. The luminescent properties were characterized by photoluminescence （PL）, X-ray excited luminescence （XEL） and vacuum ultraviolet （VUV） spectroscopy at room temperature. The synthetic LPS：Ce powder emitted a broad emission spectrum centered at about 380 nm, which should be ascribed to the 5d→4f transition of Ce3＋. Decay time of the synthetic LPS：Ce powder was measured to be only 32 ns.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1403201)the National Natural Science Foundation of China(Grant Nos.12061131001,12204231,52072170,and 11927809)the Strategic Priority Research Program(B)of Chinese Academy of Sciences(Grant No.XDB25000000)。
文摘By applying pressures up to 42 GPa on the nitrogen-doped lutetium hydride(LuH2_(±x)N_(y)),we have found a gradual change of color from dark-blue to pink-violet in the pressure region of about 12 to 21 GPa.The temperature dependence of resistivity under pressures up to 50.5 GPa shows progressively optimized metallic behavior with pressure.Interestingly,in the pressure region for the color change,a clear decrease of resistivity is observed with the increase of pressure,which is accompanied by a clear increase of the residual resistivity ratio(RRR).Fitting to the low temperature resistivity gives exponents of about 2,suggesting a Fermi-liquid behavior in the low temperature region.The general behavior in a wide temperature region suggests that the electron-phonon scattering is still the dominant one.The magnetoresistance up to 9 T in the state under a pressure of 50.5 GPa shows an almost negligible effect,which suggests that the electric conduction in the pink-violet state is dominated by a single band.It is highly desired to have theoretical efforts in understanding the evolution of color and resistivity in this interesting system.
基金supported by the National Natural Science Foundation of China (No. 21863007)
文摘Structural growth mechanism,energetics,and electronic properties of cationic,neutral,and anionic lutetium doped germanium cluster LuGen^((+/0/-))(n=6~19)were comprehensively studied by the ABCluster unbiased global search technique with a hybrid density functional theory approach.Compared to the experimental PES,the anion evolution of structure can be clearly defined as four-phase:from the adsorbed to the link structure,then to the half cage motif,and finally to the endohedral structure.The results revealed that the LuGe16-as Frank-Kasper structure with high symmetry of Td can greatly enhance the stabilities.Doped structures have shown thermodynamic stability and appropriate energy gap.These materials are suitable semiconductors.Various approaches,including quasi-spherical geometry with closed-shell model,aromaticity,UV-Vis spectra,density of states(DOS)and partial density of states(PDOS)were applied to further support the results.
