A new method of compensating for the excess micromotion along two directions in three-dimensional Coulomb crystals is reported in this paper; this method is based on shape control and optical imaging of a Coulomb crys...A new method of compensating for the excess micromotion along two directions in three-dimensional Coulomb crystals is reported in this paper; this method is based on shape control and optical imaging of a Coulomb crystal in a sectioned linear ion trap. The characteristic parameters, such as the ion numbers, temperatures, and geometric factors of different ion crystals are extracted from the images and secular motion excitation spectra. The method of controlling the shape of the ion crystals can be used in cold ion experiments, such as sympathetically cooling, structural phase transitions,and selective-control of ions, etc.展开更多
Calculating the spatial structures of ion crystals is important in ion-trapped quantum computation. Here we demon- strate that the simulated annealing method is a powerful tool to evaluate the structures of ion crysta...Calculating the spatial structures of ion crystals is important in ion-trapped quantum computation. Here we demon- strate that the simulated annealing method is a powerful tool to evaluate the structures of ion crystals. By calculating equilibrium positions of 10 ions under harmonic potential and those of 120 ions under anharmonic potential, both with the standard procedure and simulated annealing method, we find that the standard procedure to evaluate spatial structures is complicated and may be inefficient in some cases, and that the simulated annealing method is more favorable.展开更多
The inclusion crystal formed by the hexamethylenamine with p-nitrophenol has a layer type structure,and is divided or- ganic layer and inorganic layer,the latter has a width of 1.0136nm.Metal ions can enter hydrated ...The inclusion crystal formed by the hexamethylenamine with p-nitrophenol has a layer type structure,and is divided or- ganic layer and inorganic layer,the latter has a width of 1.0136nm.Metal ions can enter hydrated layer of the crystal,the con- tents of the cations and water in the crystal are determined.The XRD analysis of the layer type structure of the crystal is also giv- en.展开更多
The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions ad...The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9, t 900 s). It was concluded, that presence of copper (II) ions in a process system influenced product quality moderately advantageously. Mean size of struvite crystals enlarged by ca. 6% only. Lower concentration of phosphate (V) ions and excess of magnesium ions caused, that products of ca. 9% - 13% larger crystal mean size (up to ca.40mm) were removed from the crystallizer. Presence of struvite crystals and copper (II) hydroxide were detected analytically in the products (Cu in a product varied from 6 to 90 mg/kg). Presence of copper (II) ions favored crystallization of struvite in the form of tubular crystals.展开更多
We observed the linear-to-zigzag structural phase transition of a ^40Ca^+ crystal in a homemade linear Paul trap. The values of the total temperature of the ion crystals during the phase transition are derived using ...We observed the linear-to-zigzag structural phase transition of a ^40Ca^+ crystal in a homemade linear Paul trap. The values of the total temperature of the ion crystals during the phase transition are derived using the molecular-dynamics(MD) simulation method. A series of simulations revealed that the ratio of the radial to axial secular frequencies has a dependence on the total temperature that obeys different functional forms for linear and zigzag structures, and the transition point occurs where these functions intersect; thus, the critical value of the ratio of secular frequencies that drives the structure phase transition can be derived.展开更多
The 27Al+ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it canno...The 27Al+ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it cannot be laser-cooled directly in the absence of 167nm laser to date. This problem can be solved by sympathetic cooling. In this work, a linear Paul trap is used to trap both 40Ca+ and 27A1+ ions simultaneously, and a single Dopplercooled 40Ca+ ion is employed to sympathetically cool a single 27A1+ ion. Thus a 'bright-dark' two-ion crystal has been successfully synthesized. The temperature of the crystal has been estimated to be about 7mK by measuring the ratio of carrier and sideband spectral intensities. Finally, the dark ion is proved to be an 27Al+ ion by precise measuring of the ion crystal's secular motion frequency, which means that it is a great step for our 2Z Al+ quantum logic clock.展开更多
During the process of KDP crystal growth, metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper, KDP crystals were grown from an aqueous solution doped with different ...During the process of KDP crystal growth, metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper, KDP crystals were grown from an aqueous solution doped with different concentration of Fe^3+ dopant by traditional temperaturereduction method and "point-seed" rapid growth method. Furthermore, we examined the light scatter and measured the transmission of these KDP crystals. It is found that the dopant of Fe^3+ ion can improve the stability of the KDP growth solution when its concentration is less than 30 ppm. The effects of Fe^3+ ion on the growth habit and optical properties of KDP crystal are also obvious.展开更多
A Nd:CLNGG waveguide structure operated at wavelengths of both 632.8 nm and 1539 nm was demonstrated for the first time to our knowledge, which was produced by the 480-keV H+ ion implantation with a dose of 1.0×...A Nd:CLNGG waveguide structure operated at wavelengths of both 632.8 nm and 1539 nm was demonstrated for the first time to our knowledge, which was produced by the 480-keV H+ ion implantation with a dose of 1.0× 10^17 protons/cm2, Its propagating modes at 632.8 nm and 1539 nm were measured by the well-known prism coupling technique. The refractive index profile at either 632.8-nm wavelength or 1539-nm wavelength was optical barrier type in the proton-implanted Nd:CLNGG crystal optical waveguide, which was calculated by using the reflectivity calculation method. The near-field light intensity distributions were also simulated by the finite-difference beam propagation method in the visible and nearinfrared bands.展开更多
In this work, the fabrication and optical properties of a planar waveguide in a neodymium-doped calcium niobium gallium garnet (Nd:CNGG) crystal are reported. The waveguide is produced by proton (H+) implantatio...In this work, the fabrication and optical properties of a planar waveguide in a neodymium-doped calcium niobium gallium garnet (Nd:CNGG) crystal are reported. The waveguide is produced by proton (H+) implantation at 480 keV and a fluence of 1.0x 10^17 ions/cm2. The prism-coupling measurement is performed to obtain the dark mode of the waveguide at a wavelength of 632.8 nm. The reflectivity calculation method (RCM) is used to reconstruct the refractive index profile. The finite-difference beam propagation method (FD-BPM) is employed to calculate the guided mode profile of the waveguide. The stopping and range of ions in matter 2010 (SRIM 2010) code is used to simulate the damage profile induced by the ion implantation. The experimental and theoretical results indicate that the waveguide can confine the light propagation.展开更多
We report the fabrication of a planar waveguide in the Nd:Bi_(12)SiO_(20) crystal by multi-energy C ions at room temperature. The waveguide is annealed at 200℃, 260℃, and 300℃ in succession each for 30 min in ...We report the fabrication of a planar waveguide in the Nd:Bi_(12)SiO_(20) crystal by multi-energy C ions at room temperature. The waveguide is annealed at 200℃, 260℃, and 300℃ in succession each for 30 min in an open oven. The effective refractive index profiles at transverse electric(TE) polarization are stable after the annealing treatments. Damage distribution for multi-energy C ion implanted in Nd:Bi_(12)SiO_(20) crystal is calculated by SRIM 2010. The Raman and fluorescence spectra of the Nd:Bi_(12)SiO_(20) crystal are collected by an excitation beam at 633 nm and 473 nm, respectively. The results indicate the stabilization of the optical waveguide in Nd:Bi_(12)SiO_(20) crystal.展开更多
he crystallization features of Fe38Hi39Si10B13 metallic glass under 100 keV and 6μA/cm2 helium ion irradiation with different doses are reported. It is found that the Fe38 Ni39Si10 B13 metallic glass crystallized und...he crystallization features of Fe38Hi39Si10B13 metallic glass under 100 keV and 6μA/cm2 helium ion irradiation with different doses are reported. It is found that the Fe38 Ni39Si10 B13 metallic glass crystallized under the helium ion irradiation at the temperature lower than the ordinary thermal crystallization temperature. The preferential precipitation phase is FeSi, and followed by the eutectic phase α-Fe. The critical dose for the formation of helium bubbles in the material is around 5x10 ̄16/cm2. The sensitivity of crystallization due to the temperature rising under helium ion irradiation and the mechanism of the sequence of precipitated phase are briefly discussed.展开更多
The title compound [BrBzPy][TCNQ] (BrBzPy^+=1-(4-bromobenzyl)pyridinium cation, TCNQ = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [BrBzPy]Br and LiTCNQ in ethanol solution and it...The title compound [BrBzPy][TCNQ] (BrBzPy^+=1-(4-bromobenzyl)pyridinium cation, TCNQ = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [BrBzPy]Br and LiTCNQ in ethanol solution and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.067(3), b = 7.3089(14), c = 23.796(4)A, β = 122.011(9)°, V= 2074.6(7)A^3, Z = 4, C24H15BrN5, Mr = 453.32, Dc = 1.451 g/cm^3,μ = 2.002 mm^-1, S = 1.047, F(000) = 916, R = 0.0398 and wR = 0.0921. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [BrBzPy]^+ cations. In a TCNQ column, the centroid-to-centroid distances of the neighboring anions of TCNQ are 3.2693 and 4.9464 A, respectively.展开更多
A novel compound [(CNBz)2Im]2(TCNQ)3(CH3CN)((CNBz)2Im = 1,3-bis(4-cyano-benzyl) imidazole cation,TCNQ-1 = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [(CNBz)2Im]Br and Li...A novel compound [(CNBz)2Im]2(TCNQ)3(CH3CN)((CNBz)2Im = 1,3-bis(4-cyano-benzyl) imidazole cation,TCNQ-1 = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [(CNBz)2Im]Br and LiTCNQ in water and its structure was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/c with a = 10.1823(17),b = 20.292(3),c = 16.952(3) ,β = 104.73(0)°,V = 3387.6(10)3,Z = 4,C39H24N11,Mr = 646.69,Dc = 1.268 g/cm3,μ = 0.080 mm-1 and F(000) = 1340.The structure was solved by direct methods and refined to R = 0.0596 and wR = 0.0911 for 2690 observed reflections(Ⅰ 〉 2σ(Ⅰ)).The most prominent structural feature is that there are two types of TCNQ entries(TCNQ-1 and TCNQ0) in agreement with the IR spectra analysis of the compound.展开更多
A comprehensive investigation is carried out to compare the spectroscopic properties, absorption saturation behaviors and lasing properties of a Yb ion in tetragonal LuPO4 and LuVO4 isomorphic crystals. Significant di...A comprehensive investigation is carried out to compare the spectroscopic properties, absorption saturation behaviors and lasing properties of a Yb ion in tetragonal LuPO4 and LuVO4 isomorphic crystals. Significant distinctions are revealed in many aspects of the lasing behavior for the Yb ion doped in the two crystal hosts, and Yb:LuPO_4 proves to be superior to Yb:LuVO4 since it enables efficient laser action to be much more easily achieved. With a 0.6 mm thick crystal plate of Yb:LuPO4, an output power of 3.30 W can be generated with an optical–optical conversion efficiency of 50.8%; whereas with a 2 mm long miniature crystal rod, the output power produced can reach 8.35 W with an optical–optical conversion efficiency of 46.7%.展开更多
A novel compound [Cl2Bz(3-MeQl) ](TCNQ) ([Cl2Bz(3-MeQl) ]^+ = 1-(3,4-dichlo-robenzyl) 3-methlquinoline cation,TCNQ-= 7,7,8,8-tetracyanoquinodimethanide anion) has been synthesized by the reaction of [Cl2Bz...A novel compound [Cl2Bz(3-MeQl) ](TCNQ) ([Cl2Bz(3-MeQl) ]^+ = 1-(3,4-dichlo-robenzyl) 3-methlquinoline cation,TCNQ-= 7,7,8,8-tetracyanoquinodimethanide anion) has been synthesized by the reaction of [Cl2Bz(3-MeQl) ]Br and LiTCNQ,and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic,space group P21/c. The structure analysis shows that the anions are stacked into a column with isolated π-dimers,and there is one type of TCNQ entries(TCNQ^-) ,in agreement with the IR spectra analysis and density functional theory calculations of the compound. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [Cl2Bz(3-MeQl)]+ cations.展开更多
The replaced site of Eu^(2+) ion is dependent on the electronegativity difference of the cations in complex fluorides.In the mixed fluoride KMgF_3:Eu^(2+),Eu^(2+) ion occupies K^+ site,its emission spectrum is a sharp...The replaced site of Eu^(2+) ion is dependent on the electronegativity difference of the cations in complex fluorides.In the mixed fluoride KMgF_3:Eu^(2+),Eu^(2+) ion occupies K^+ site,its emission spectrum is a sharp line and its valence-state is stable.展开更多
Alluaudite-type NaMnV2(PO4)3 single crystal was successfully synthesized in the NaCl molten-salt media. The single-crystal diffraction data analysis shows that NaMnV2(PO4)3 crystallizes in monoclinic C2/c space group ...Alluaudite-type NaMnV2(PO4)3 single crystal was successfully synthesized in the NaCl molten-salt media. The single-crystal diffraction data analysis shows that NaMnV2(PO4)3 crystallizes in monoclinic C2/c space group with a = 12.098(2), b = 12.415(2), c = 6.4543(11)?, β = 114.614(2)°, V = 881.3(3) ?3, Mr = 464.64, Dc = 3.50158 g/cm3, μ(Mo Kα) = 4.046 mm-1, F(000) = 892.4 and Z = 2. The structure consists of MnO6, VO6 octahedra and PO4 tetrahedra, which form a three-dimensional architecture with two sets of large Na+ tunnels. The intercalation/deintercalation properties of NaMnV2(PO4)3 as positive and negative electrodes were tested in sodium batteries.展开更多
Phosphate (V) ions were continuously removed from synthetic wastewater containing inorganic impurities using magnesium and ammonium ions. The product was magnesium ammonium phosphate (V) hexahydrate, struvite, MgNH4PO...Phosphate (V) ions were continuously removed from synthetic wastewater containing inorganic impurities using magnesium and ammonium ions. The product was magnesium ammonium phosphate (V) hexahydrate, struvite, MgNH4PO4 × 6H2O. Research ran in stoichiometric conditions in DT MSMPR type crystallizer with internal circulation of suspension. Increase in process environment pH from 9 to 11 resulted in 3-time decrease of mean struvite crystals size (from 40.1 to12.6mm). Elongation of mean residence time of suspension in a crystallizer up to 3600 s resulted in improvement of the product quality. Mean size of struvite crystals enlarged up to50.2mm. Based on kinetic calculations results (SIG MSMPR model) it was concluded, that linear struvite crystal growth rate varied within 5.04 × 10–9 – 1.69 × 10–8 m/s range, whereas nucleation rate within 1.4 × 107 – 1.7 × 1010 1/(s m3) limits. In solid product, besides struvite, also all impurities present in wastewater were identified analytically as hydroxides, phosphates and other salts.展开更多
Observation under high resolution electron microscope shows that the continuous bombing of high speed ions produces a great amount of vacant site defects.The assembly of vacancies forms vacant dish,and the collapase o...Observation under high resolution electron microscope shows that the continuous bombing of high speed ions produces a great amount of vacant site defects.The assembly of vacancies forms vacant dish,and the collapase of vacant dish forms stacking fault tetrahedrons and oth- er crystal defects.The interfaces between phase ε(Fe_(2-3)N)and phase γ'(Fe_4N)are smooth, straight and coherent,and they have the orientation relationships of(11)//(0001)and [110]/[110] .展开更多
Based on a single ion model, Hamiltonian of the simplest form about magnetocrystalline anisotropy for Tb3+ ion was solved by using the numerical method. The relation between the stabilization energy, crystal field coe...Based on a single ion model, Hamiltonian of the simplest form about magnetocrystalline anisotropy for Tb3+ ion was solved by using the numerical method. The relation between the stabilization energy, crystal field coefficient B20 and the magnetic exchange interaction was studied as temperature approaches to 0 K. The results show that the stabilization energy contributed by Tb3+ is linear with crystal field coefficient B20 approximately, but it is insensitive to the change of magnetic exchange interaction for the strong magnetic substances such as TbCo5, Tb2Co17 and Tb2Fe14B compounds.展开更多
基金supported by the National Basic Research Program of China(Grant Nos.2012CB821301 and 2010CB832803)the National Natural Science Foundation of China(Grant Nos.11004222 and 91121016)the Fund from Chinese Academy of Sciences
文摘A new method of compensating for the excess micromotion along two directions in three-dimensional Coulomb crystals is reported in this paper; this method is based on shape control and optical imaging of a Coulomb crystal in a sectioned linear ion trap. The characteristic parameters, such as the ion numbers, temperatures, and geometric factors of different ion crystals are extracted from the images and secular motion excitation spectra. The method of controlling the shape of the ion crystals can be used in cold ion experiments, such as sympathetically cooling, structural phase transitions,and selective-control of ions, etc.
基金supported by the National Basic Research Program of China(Grant No.2016YFA0301903)the National Natural Science Foundation of China(Grant Nos.11304387,11174370,61632021,61205108,and 11305262)the Research Plan Project of National University of Defense Technology(Grant No.ZK16-03-04)
文摘Calculating the spatial structures of ion crystals is important in ion-trapped quantum computation. Here we demon- strate that the simulated annealing method is a powerful tool to evaluate the structures of ion crystals. By calculating equilibrium positions of 10 ions under harmonic potential and those of 120 ions under anharmonic potential, both with the standard procedure and simulated annealing method, we find that the standard procedure to evaluate spatial structures is complicated and may be inefficient in some cases, and that the simulated annealing method is more favorable.
基金This work is supported by the Excellent Young Tcachers Foundation the State Education Commission of China
文摘The inclusion crystal formed by the hexamethylenamine with p-nitrophenol has a layer type structure,and is divided or- ganic layer and inorganic layer,the latter has a width of 1.0136nm.Metal ions can enter hydrated layer of the crystal,the con- tents of the cations and water in the crystal are determined.The XRD analysis of the layer type structure of the crystal is also giv- en.
文摘The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9, t 900 s). It was concluded, that presence of copper (II) ions in a process system influenced product quality moderately advantageously. Mean size of struvite crystals enlarged by ca. 6% only. Lower concentration of phosphate (V) ions and excess of magnesium ions caused, that products of ca. 9% - 13% larger crystal mean size (up to ca.40mm) were removed from the crystallizer. Presence of struvite crystals and copper (II) hydroxide were detected analytically in the products (Cu in a product varied from 6 to 90 mg/kg). Presence of copper (II) ions favored crystallization of struvite in the form of tubular crystals.
基金Project supported by the National Basic Research Program of China(Grant Nos.2010CB832803 and 2012CB821301)the National Natural Science Foundation of China(Grant Nos.11004222 and 91121016)the Chinese Academy of Sciences
文摘We observed the linear-to-zigzag structural phase transition of a ^40Ca^+ crystal in a homemade linear Paul trap. The values of the total temperature of the ion crystals during the phase transition are derived using the molecular-dynamics(MD) simulation method. A series of simulations revealed that the ratio of the radial to axial secular frequencies has a dependence on the total temperature that obeys different functional forms for linear and zigzag structures, and the transition point occurs where these functions intersect; thus, the critical value of the ratio of secular frequencies that drives the structure phase transition can be derived.
基金Supported by the National High Technology Research and Development Program of China under Grant No 2012AA120701the National Natural Science Foundation of China under Grant No 11174326
文摘The 27Al+ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it cannot be laser-cooled directly in the absence of 167nm laser to date. This problem can be solved by sympathetic cooling. In this work, a linear Paul trap is used to trap both 40Ca+ and 27A1+ ions simultaneously, and a single Dopplercooled 40Ca+ ion is employed to sympathetically cool a single 27A1+ ion. Thus a 'bright-dark' two-ion crystal has been successfully synthesized. The temperature of the crystal has been estimated to be about 7mK by measuring the ratio of carrier and sideband spectral intensities. Finally, the dark ion is proved to be an 27Al+ ion by precise measuring of the ion crystal's secular motion frequency, which means that it is a great step for our 2Z Al+ quantum logic clock.
基金the State High Technology Program for Inertial Confinement Fusion and National Science Foundation (No.59823003)Project of United Foundation (No.10676019)Youth Scientist Fund of Shandong Province (Nos. 2004BS04022 and 03BS079)
文摘During the process of KDP crystal growth, metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper, KDP crystals were grown from an aqueous solution doped with different concentration of Fe^3+ dopant by traditional temperaturereduction method and "point-seed" rapid growth method. Furthermore, we examined the light scatter and measured the transmission of these KDP crystals. It is found that the dopant of Fe^3+ ion can improve the stability of the KDP growth solution when its concentration is less than 30 ppm. The effects of Fe^3+ ion on the growth habit and optical properties of KDP crystal are also obvious.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11405041 and 61177084)the Nanjing University of Posts and Telecommunications Scientific Foundation(NUPTSF),China(Grant No.NY214159)the RCOCET,China(Grant No.ZSF0401)
文摘A Nd:CLNGG waveguide structure operated at wavelengths of both 632.8 nm and 1539 nm was demonstrated for the first time to our knowledge, which was produced by the 480-keV H+ ion implantation with a dose of 1.0× 10^17 protons/cm2, Its propagating modes at 632.8 nm and 1539 nm were measured by the well-known prism coupling technique. The refractive index profile at either 632.8-nm wavelength or 1539-nm wavelength was optical barrier type in the proton-implanted Nd:CLNGG crystal optical waveguide, which was calculated by using the reflectivity calculation method. The near-field light intensity distributions were also simulated by the finite-difference beam propagation method in the visible and nearinfrared bands.
基金supported by the National Natural Science Foundation of China(Grant Nos.11405041,61405240,61077070,61177086,51002181,and 61177084)the Scientific Research Starting Foundation for New Teachers of Nanjing University of Posts and Telecommunications(NUPTSF)(Grant No.NY214159)the Research Center of Optical Communications Engineering&Technology,Jiangsu Province,China(Grant No.ZSF0401)
文摘In this work, the fabrication and optical properties of a planar waveguide in a neodymium-doped calcium niobium gallium garnet (Nd:CNGG) crystal are reported. The waveguide is produced by proton (H+) implantation at 480 keV and a fluence of 1.0x 10^17 ions/cm2. The prism-coupling measurement is performed to obtain the dark mode of the waveguide at a wavelength of 632.8 nm. The reflectivity calculation method (RCM) is used to reconstruct the refractive index profile. The finite-difference beam propagation method (FD-BPM) is employed to calculate the guided mode profile of the waveguide. The stopping and range of ions in matter 2010 (SRIM 2010) code is used to simulate the damage profile induced by the ion implantation. The experimental and theoretical results indicate that the waveguide can confine the light propagation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11404194 and 11274188)the Promotive Research Fund for Excellent Young and Middle-aged Scientisits of Shandong Province,China(Grant No.BS2015SF003)+3 种基金the China Postdoctoral Science Foundation(Grant Nos.2015M582053 and 2016T90609)the Qingdao Municipal Postdoctoral Application Research Project,China(Grant No.2015131)the State Key Laboratory of Nuclear Physics and Technology at Peking University,Chinathe State Key Laboratory of Crystal Materials and Key Laboratory of Particle Physics and Particle Irradiation(MOE)at Shandong University,China
文摘We report the fabrication of a planar waveguide in the Nd:Bi_(12)SiO_(20) crystal by multi-energy C ions at room temperature. The waveguide is annealed at 200℃, 260℃, and 300℃ in succession each for 30 min in an open oven. The effective refractive index profiles at transverse electric(TE) polarization are stable after the annealing treatments. Damage distribution for multi-energy C ion implanted in Nd:Bi_(12)SiO_(20) crystal is calculated by SRIM 2010. The Raman and fluorescence spectra of the Nd:Bi_(12)SiO_(20) crystal are collected by an excitation beam at 633 nm and 473 nm, respectively. The results indicate the stabilization of the optical waveguide in Nd:Bi_(12)SiO_(20) crystal.
文摘he crystallization features of Fe38Hi39Si10B13 metallic glass under 100 keV and 6μA/cm2 helium ion irradiation with different doses are reported. It is found that the Fe38 Ni39Si10 B13 metallic glass crystallized under the helium ion irradiation at the temperature lower than the ordinary thermal crystallization temperature. The preferential precipitation phase is FeSi, and followed by the eutectic phase α-Fe. The critical dose for the formation of helium bubbles in the material is around 5x10 ̄16/cm2. The sensitivity of crystallization due to the temperature rising under helium ion irradiation and the mechanism of the sequence of precipitated phase are briefly discussed.
基金supported by the National Natural Science Foundation of China (No. 20371002, 20771006)
文摘The title compound [BrBzPy][TCNQ] (BrBzPy^+=1-(4-bromobenzyl)pyridinium cation, TCNQ = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [BrBzPy]Br and LiTCNQ in ethanol solution and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.067(3), b = 7.3089(14), c = 23.796(4)A, β = 122.011(9)°, V= 2074.6(7)A^3, Z = 4, C24H15BrN5, Mr = 453.32, Dc = 1.451 g/cm^3,μ = 2.002 mm^-1, S = 1.047, F(000) = 916, R = 0.0398 and wR = 0.0921. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [BrBzPy]^+ cations. In a TCNQ column, the centroid-to-centroid distances of the neighboring anions of TCNQ are 3.2693 and 4.9464 A, respectively.
基金Supported by the National Natural Science Foundation of China (No. 20771006)Natural Science Foundation of Anhui Province (No. 2006kj042a)Education Committee of Anhui Province (KJ2008B005)
文摘A novel compound [(CNBz)2Im]2(TCNQ)3(CH3CN)((CNBz)2Im = 1,3-bis(4-cyano-benzyl) imidazole cation,TCNQ-1 = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [(CNBz)2Im]Br and LiTCNQ in water and its structure was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/c with a = 10.1823(17),b = 20.292(3),c = 16.952(3) ,β = 104.73(0)°,V = 3387.6(10)3,Z = 4,C39H24N11,Mr = 646.69,Dc = 1.268 g/cm3,μ = 0.080 mm-1 and F(000) = 1340.The structure was solved by direct methods and refined to R = 0.0596 and wR = 0.0911 for 2690 observed reflections(Ⅰ 〉 2σ(Ⅰ)).The most prominent structural feature is that there are two types of TCNQ entries(TCNQ-1 and TCNQ0) in agreement with the IR spectra analysis of the compound.
基金Project supported by the National Natural Science Foundation of China(Grant No.11574170)
文摘A comprehensive investigation is carried out to compare the spectroscopic properties, absorption saturation behaviors and lasing properties of a Yb ion in tetragonal LuPO4 and LuVO4 isomorphic crystals. Significant distinctions are revealed in many aspects of the lasing behavior for the Yb ion doped in the two crystal hosts, and Yb:LuPO_4 proves to be superior to Yb:LuVO4 since it enables efficient laser action to be much more easily achieved. With a 0.6 mm thick crystal plate of Yb:LuPO4, an output power of 3.30 W can be generated with an optical–optical conversion efficiency of 50.8%; whereas with a 2 mm long miniature crystal rod, the output power produced can reach 8.35 W with an optical–optical conversion efficiency of 46.7%.
基金Supported by the National Natural Science Foundation of China (Nos.20771006 and 20901004)
文摘A novel compound [Cl2Bz(3-MeQl) ](TCNQ) ([Cl2Bz(3-MeQl) ]^+ = 1-(3,4-dichlo-robenzyl) 3-methlquinoline cation,TCNQ-= 7,7,8,8-tetracyanoquinodimethanide anion) has been synthesized by the reaction of [Cl2Bz(3-MeQl) ]Br and LiTCNQ,and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic,space group P21/c. The structure analysis shows that the anions are stacked into a column with isolated π-dimers,and there is one type of TCNQ entries(TCNQ^-) ,in agreement with the IR spectra analysis and density functional theory calculations of the compound. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [Cl2Bz(3-MeQl)]+ cations.
基金Project supported by the National Natural Science Foundation of China
文摘The replaced site of Eu^(2+) ion is dependent on the electronegativity difference of the cations in complex fluorides.In the mixed fluoride KMgF_3:Eu^(2+),Eu^(2+) ion occupies K^+ site,its emission spectrum is a sharp line and its valence-state is stable.
基金supported by the Fund of Education Committee of Shaanxi Province(No.16JS103)the Natural Science Basic Research Plan in Shaanxi Province(No.2018JM2021)
文摘Alluaudite-type NaMnV2(PO4)3 single crystal was successfully synthesized in the NaCl molten-salt media. The single-crystal diffraction data analysis shows that NaMnV2(PO4)3 crystallizes in monoclinic C2/c space group with a = 12.098(2), b = 12.415(2), c = 6.4543(11)?, β = 114.614(2)°, V = 881.3(3) ?3, Mr = 464.64, Dc = 3.50158 g/cm3, μ(Mo Kα) = 4.046 mm-1, F(000) = 892.4 and Z = 2. The structure consists of MnO6, VO6 octahedra and PO4 tetrahedra, which form a three-dimensional architecture with two sets of large Na+ tunnels. The intercalation/deintercalation properties of NaMnV2(PO4)3 as positive and negative electrodes were tested in sodium batteries.
文摘Phosphate (V) ions were continuously removed from synthetic wastewater containing inorganic impurities using magnesium and ammonium ions. The product was magnesium ammonium phosphate (V) hexahydrate, struvite, MgNH4PO4 × 6H2O. Research ran in stoichiometric conditions in DT MSMPR type crystallizer with internal circulation of suspension. Increase in process environment pH from 9 to 11 resulted in 3-time decrease of mean struvite crystals size (from 40.1 to12.6mm). Elongation of mean residence time of suspension in a crystallizer up to 3600 s resulted in improvement of the product quality. Mean size of struvite crystals enlarged up to50.2mm. Based on kinetic calculations results (SIG MSMPR model) it was concluded, that linear struvite crystal growth rate varied within 5.04 × 10–9 – 1.69 × 10–8 m/s range, whereas nucleation rate within 1.4 × 107 – 1.7 × 1010 1/(s m3) limits. In solid product, besides struvite, also all impurities present in wastewater were identified analytically as hydroxides, phosphates and other salts.
文摘Observation under high resolution electron microscope shows that the continuous bombing of high speed ions produces a great amount of vacant site defects.The assembly of vacancies forms vacant dish,and the collapase of vacant dish forms stacking fault tetrahedrons and oth- er crystal defects.The interfaces between phase ε(Fe_(2-3)N)and phase γ'(Fe_4N)are smooth, straight and coherent,and they have the orientation relationships of(11)//(0001)and [110]/[110] .
文摘Based on a single ion model, Hamiltonian of the simplest form about magnetocrystalline anisotropy for Tb3+ ion was solved by using the numerical method. The relation between the stabilization energy, crystal field coefficient B20 and the magnetic exchange interaction was studied as temperature approaches to 0 K. The results show that the stabilization energy contributed by Tb3+ is linear with crystal field coefficient B20 approximately, but it is insensitive to the change of magnetic exchange interaction for the strong magnetic substances such as TbCo5, Tb2Co17 and Tb2Fe14B compounds.