Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics ...Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics in fusion and astrophysical plasmas. In this work, we mainly focus on reviewing our two projects performed in the past decade. One is about the ions with Z■30 that are generally of astrophysical interest, and the other one is about the highly charged krypton(Z = 36)and tungsten(Z = 74) ions that are relevant in research of magnetic confinement fusion. Two different and independent methods, namely, multiconfiguration Dirac–Hartree–Fock(MCDHF) and the relativistic many-body perturbation theory(RMBPT) are usually used in our studies. As a complement/extension to our previous works for highly charged tungsten ions with open M-shell and open N-shell, we also mainly focus on presenting and discussing our complete RMBPT and MCDHF calculations for the excitation energies, wavelengths, electric dipole(E1), magnetic dipole(M1), electric quadrupole(E2), and magnetic quadrupole(M2) transition properties, and level lifetimes for the lowest 148 levels belonging to the 3l3configurations in Al-like W61+. We also summarize the uncertainties of our systematical theoretical calculations, by cross-checking/validating our datasets from our RMBPT and MCDHF calculations, and by detailed comparisons with available accurate observations and other theoretical calculations. The data are openly available in Science Data Bank at https://doi.org/10.57760/sciencedb.10569.展开更多
Magnesium gluconate is a classical organometallic pharmaceutical compound used for the prevention and treatment of hypomagnesemia as a source of magnesium ion. The present research described the in-depth study on soli...Magnesium gluconate is a classical organometallic pharmaceutical compound used for the prevention and treatment of hypomagnesemia as a source of magnesium ion. The present research described the in-depth study on solid state properties viz. physicochemical and thermal properties of magnesium gluconate using sophisticated analytical techniques like Powder X-ray diffraction(PXRD), particle size analysis(PSA),Fourier transform infrared(FT-IR) spectrometry, ultraviolet–visible(UV–Vis) spectroscopy, thermogravimetric analysis(TGA)/differential thermogravimetric analysis(DTG), and differential scanning calorimetry(DSC).Magnesium gluconate was found to be crystalline in nature along with the crystallite size ranging from 14.10 to47.35 nm. The particle size distribution was at d(0.1)=6.552 μm, d(0.5)=38.299 μm, d(0.9)=173.712 μm and D(4,3)=67.122 μm along with the specific surface area of 0.372 m^2/g. The wavelength for the maximum absorbance was at 198.0 nm. Magnesium gluconate exhibited 88.51% weight loss with three stages of thermal degradation process up to 895.18 °C from room temperature. The TGA/DTG thermograms of the analyte indicated that magnesium gluconate was thermally stable up to around 165 °C. Consequently, the melting temperature of magnesium gluconate was found to be 169.90 °C along with the enthalpy of fusion of 308.7 J/g.Thus, the authors conclude that the achieved results from this study are very useful in pharmaceutical and nutraceutical industries for the identification, characterization and qualitative analysis of magnesium gluconate for preformulation studies and also for developing magnesium gluconate based novel formulation.展开更多
Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, ...Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of each energy levels for Er^(3+) were calculated by Judd-Ofelt theory, and stimulated emission cross-section of (()~4I_(13/2))→(()~4I_(15/2)) transition was calculated by McCumber theory. The results show that fluorescence full width at half maximum and stimulated emission cross-section of Er^(3+)-doped heavy metal oxyfluoride silicate glass are broad and large, respectively. Compared with other host glasses, the gain bandwidth property of Er^(3+)-doped heavy metal oxyfluoride silicate glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses.展开更多
The Er-single-doped and Er/Ce-codoped La3Ga5SiO14 polycrystalline powders are synthesized by the solid-phase synthesis method. The room-temperature luminescence spectra of the samples are investigated. The Near-infrar...The Er-single-doped and Er/Ce-codoped La3Ga5SiO14 polycrystalline powders are synthesized by the solid-phase synthesis method. The room-temperature luminescence spectra of the samples are investigated. The Near-infrared- region spectroscopic properties of Er3+ ions in the La3GasSiO14 systems are analysed with Judd-Ofelt theory and rate equations. The effective deactivating effect of Ce3+ ions on Er3+ ions is confirmed.展开更多
A new copper(Ⅱ) complex [Cu2(MNA)2(2,2‘-bipy)2]·2.5H2 O with methy-5-norbornene-2,3-dicarboxylic acid(MNA) and 2,2’-bipyridine as ligands has been synthesized in the mixed solvents of DMF and water.It ...A new copper(Ⅱ) complex [Cu2(MNA)2(2,2‘-bipy)2]·2.5H2 O with methy-5-norbornene-2,3-dicarboxylic acid(MNA) and 2,2’-bipyridine as ligands has been synthesized in the mixed solvents of DMF and water.It crystallizes in monoclinic,space group P 1,with a = 10.4191(11),b = 12.8883(13),c = 16.1114(16) A,α = 70.8090(10),β = 80.568(2),γ = 77.440(2)o,V = 1984.3(4) A^3,Dc = 1.551 g/cm^3,Z = 2,F(000) = 962,the final GOOF = 1.051,R = 0.0431 and w R= 0.0980.The crystal structure shows that the whole molecule consists of two independent dinuclear units,in which two copper ions are bridged by two μ2-η^1:η^0 3-carboxylate groups of MNA^2-.The coordination environment of Cu(Ⅱ) ion is Cu O3N2,giving a distorted square pyramidal geometry.The spectroscopic characterization,thermal stability and magnetic properties of the complex were investigated.展开更多
A series of novel Er^3+/Yb^3+ co-doped (85- x ) TeO2-15WO3-xB2O3 (TWB;x=2%,5%,8%(mole fraction) ) glasses were prepared. Influence of B203 on the spectroscopic properties of Er^3+/Yb^3+ co-doped tungsten-tel...A series of novel Er^3+/Yb^3+ co-doped (85- x ) TeO2-15WO3-xB2O3 (TWB;x=2%,5%,8%(mole fraction) ) glasses were prepared. Influence of B203 on the spectroscopic properties of Er^3+/Yb^3+ co-doped tungsten-tellurite glasses were investigated. It is found that the intensity of 1.5μm fluorescence, lifetime of the ^4I13/2 level and upconversion fluorescence all decrease with the increase of B2O3 content. The product of full width at half maximum (FWHM) and stimulated emission cross-section (σe^peak) of Er^3+ :^4I13/2→^4I15/2 transition has an optimum when B203 is 5% (mole fraction). The emission spectra of Er^3+ : ^4I13/2→^4I15/2 transition was analyzed using peak-fit routine, and an equivalent four-level system was proposed to estimate the stark splitting for the 411512 and ^4I13/2 levels of Er^3+ ions in TWB glasses at room temperature.展开更多
Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-toly...Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-tolyl)-2,2′:6′,2″-terpyridine, salen = N,N?-ethylenebis-(salicylideneaminato)dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in orthorhombic Pbca space group and the asymmetric unit of 1 contains one[-NC-RuⅡ(ttpy)(CN)(m-CN)-Mn Ⅲ-(salen)-] molecule. In the structure of 1, each [Ru Ⅱ(ttpy)(CN)3]-connects two [MnⅢ(salen)]+ with two cyanide groups in a cis-conformation, and in turn each[MnⅢ(salen)]+ unit links two [RuⅡ(ttpy)(CN)3]-building blocks in a trans-conformation, resulting in a 1D [-NC-RuⅡ-CN-MnⅢ-]n chain. Furthermore, the electronic absorption spectra and luminescence spectroscopy of complex 1 have also been studied.展开更多
This paper reports the growth, X-ray diffraction and spectroscopy of Nd3+:Sr3Gd2(BO3)4 crystal. A Nd3+:Sr3Gd2(BO3)4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3+...This paper reports the growth, X-ray diffraction and spectroscopy of Nd3+:Sr3Gd2(BO3)4 crystal. A Nd3+:Sr3Gd2(BO3)4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3+:Sr3Gd2(BO3)4 crystal belongs to the orthorhombic system, space group Pnma (D2h) with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3+:Sr3Gd2(BO3)4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.展开更多
This work is a contribution of theoretical chemistry to the classification of some non-steroidal anti-inflammatory drugs (NSAIDs). Indeed, research on the efficacy of NSAIDs has shown that no NSAID is recognized as th...This work is a contribution of theoretical chemistry to the classification of some non-steroidal anti-inflammatory drugs (NSAIDs). Indeed, research on the efficacy of NSAIDs has shown that no NSAID is recognized as the most efficient anti-inflammatory drug. We have made a theoretical study of diclofenac, bromfenac and amfenac, in order to compare their efficacy from some physicochemical properties. To do this, we used the DFT and TD-DTF methods at the B3LYP/6-311+G(d, p) level theory. The lipophilicity study shows that diclofenac and bromfenac are very lipophilic. Acidity study shows that diclofenac is more acid than bromfenac and amfenac. The results from molecular orbital and the TD-DFT calculations reveal that for the three NSAIDs, the lowest energy transition is due to the excitation from HOMO to LUMO. The absorption energy corresponding to H→L transition is comparable with the energy gap value. Our findings have shown that bromfenac is more reactive than amfenac, which is more reactive than diclofenac.展开更多
The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine...The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.展开更多
The syntheses of porphyrin-phthalocyanine heterodimers with flexible polyatomic chains especially designed for the studies of intramolecular photoinduced processes are presented along with the effect of mutual orienta...The syntheses of porphyrin-phthalocyanine heterodimers with flexible polyatomic chains especially designed for the studies of intramolecular photoinduced processes are presented along with the effect of mutual orientation of the chromophore subunits on intramolecular energy transfer efficiency.展开更多
A series of oxyfluoride glasses with the compositions of 75 mol% TeO2, 10 mol% Nb2O5, (15 mol%-x) BaO, x BaF2 (x =0 mol%, 5 mol%, 10 mol%, 15 mol%) doped with Yb2O3 were prepared by the melt-quenching method. Thei...A series of oxyfluoride glasses with the compositions of 75 mol% TeO2, 10 mol% Nb2O5, (15 mol%-x) BaO, x BaF2 (x =0 mol%, 5 mol%, 10 mol%, 15 mol%) doped with Yb2O3 were prepared by the melt-quenching method. Their emission cross-sections, fluorescence lifetimes, and gain properties were investigated by using the absorption spectra and the fluorescence decay curves. The results show that by substituting BaF2 for BaO, the emission cross-section decreases from 1.37 pm^2 to 1.21 pm^2, and the fluorescence lifetime increases from 0.71 ms to 0.96 ms. These properties indicate that this oxyfluoride tellurite glass may have potential uses as the Yb2O3-doped gain medium in a solid laser.展开更多
A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction o...A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction of N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine with 2-fluoroiodobenzene (yield: 75%) and structurally characterized. It crystallizes in monoclinic, space group P21/n with a = 9.820(7), b = 14.305(11), c = 10.233(8) , β = 108.973(9)o, V = 1359.3(18) 3, Z = 2, Dc = 1.282 g/cm3, μ(MoKα) = 0.084 mm-1, F(000) = 548, S = 1.018, the final R = 0.0439 and wR = 0.0928. It presents a linear centrosymmetric framework constituted by a linkage of biphenyl as a bridge and two fluorinated diphenylamine moieties. The UV-Vis absorption and fluorescence spectra of the title compound were also investigated. This compound emits intense blue fluorescence with a peak wavelength of 406 nm in film.展开更多
In order to develop a novel electric light source, the doped high-silica glass was studied on the preparation and spectroscopic properties. ne porous glasses were made firstly and were then immersed in the solution co...In order to develop a novel electric light source, the doped high-silica glass was studied on the preparation and spectroscopic properties. ne porous glasses were made firstly and were then immersed in the solution containing Ce ion. Thereafter, the high-silica glasses containing Ce ion were prepared by sintering the porous preform. The spectroscopic properties were studied before and after heath treatment in H-2. The experimental results indicate that the suitable temperature schedules are the most important to prepare doped high-silica glass. The study of the spectra shows that Ce ion can be reduced to low valence state when it is heat-treated in H-2. It can be used to adjust the UV cut-off wavelength of high-silica glass by changing the valence state of Ce ion.展开更多
The Er^(3+)-doped TeO_2-WO_3-ZnO-ZnF_2(TWZOF) glasses were prepared. The absorption spectra, 1.5 μm emission spectra and fluorescence lifetimes of Er^(3+), excited at 970 nm, were measured. The J-O parameters Ω_ t (...The Er^(3+)-doped TeO_2-WO_3-ZnO-ZnF_2(TWZOF) glasses were prepared. The absorption spectra, 1.5 μm emission spectra and fluorescence lifetimes of Er^(3+), excited at 970 nm, were measured. The J-O parameters Ω_ t (t =2, 4, 6), absorption and emission cross-sections were calculated. The dependence of the 1.5 μm emission intensity, fluorescence lifetime and bandwidth of the Er^(3+) emission upon the contents of ZnF_2 in glass were investigated. In TWZOF glass, Er^(3+) ions had a broad emission profile around 1.5 μm with the maximum FWHM of 83 nm. With the increasing of the content of ZnF_2, the emission intensity at peak wavelength and the fluorescence lifetime of Er^(3+) at 1.5 μm increase.展开更多
The Nd^3+-doped pared. The absorption and tellurite glasses were preemission spectra of Nd^3 +- doped tellurite glasses at room temperature were measured. The Judd-Ofelt parameters (Ω2, Ω4, Ω6) of the glasses w...The Nd^3+-doped pared. The absorption and tellurite glasses were preemission spectra of Nd^3 +- doped tellurite glasses at room temperature were measured. The Judd-Ofelt parameters (Ω2, Ω4, Ω6) of the glasses were calculated from measured absorption spectra. The calculation results of luminescence properties (A, β, τrad, σ) of Nd^3+ ions in the tellurite were glasses were given. Spectroscopic properties, concentration quenching in these kinds of the glasses were investigated. The results indicate that the tellurite glasses with composition of 70% TeO2, 20% ZnO, ( 10 - x ) % La2O3, x % Nd2O3 ( mol% ) show high emission cross section and low phonon energy. The fluorescent intensity and the emission cross section have a maxi- mum value at x = 0.5, namely, the optimum Nd^3 + ion concentration in the tellurite glass is 0.5% (1.93 × 10^20 ions·cm^-3). The fluorescence properties of Nd^3+ measured are basically in accord with the calculated results.展开更多
A new serials of Er^3+/Yb^3+ co-doped tellurite-silicate glasses were prepared by the technique of high-temperature mehing. The thermal stability, absorption spectra, emission spectra and upconversion spectra were m...A new serials of Er^3+/Yb^3+ co-doped tellurite-silicate glasses were prepared by the technique of high-temperature mehing. The thermal stability, absorption spectra, emission spectra and upconversion spectra were measured and investigated. It is found that these kinds of glasses have good thermal stability, broad FWHM and large stimulated emission cross-section. The three upconversion emission at 525, 546, 658 nm, corresponding to the ^2H11/2→^4Ⅰ15/2, ^4S3/2→4^Ⅰ15/2 and ^F9/2→^4Ⅰ15/2 transitions of Dr^3+ ions,展开更多
The potential energy curves (PECs) of 14 A-S states for magnesium chloride (MgC1) have been calculated by using multi-reference configuration interaction method with Davidson correction (MRCI + Q). The core-val...The potential energy curves (PECs) of 14 A-S states for magnesium chloride (MgC1) have been calculated by using multi-reference configuration interaction method with Davidson correction (MRCI + Q). The core-valence correlation (CV), scalar relativistic effect, and spin-orbit coupling (SOC) effect are considered in the electronic structure computations. The spectroscopic constants of X2∑+ and A2П states have been obtained, which are in good agreement with the existing theoretical and experimental results. Furthermore, other higher electronic states are also characterized. The permanent dipole moments (PDMs) of A-S states and the spinorbit (SO) matrix elements between A-S states are also computed. The results indicate that the abrupt changes of PDMs and the SO matrix elements are attributed to the avoided crossing between the states with the same symmetry. The SOC effect is taken into account with Breit-Panli operator, which makes the 14 A-S states split into 30 Ωstates, and leads to a double-well potential of the Ω =(3)1/2 state. The energy splitting for the A2I-I is calculated to be 53.61 cm-1 and in good agreement with the experimental result 54.47 cm-1. The transition dipole moments (TDMs), Franck-Condon factors (FCFs), and the corresponding radiative lifetimes of the selected transitions from excited Ω states to the ground state X2∑+ 1/2 have been reported. The computed radiative lifetimes tV1, of low-lying excitesΩ states are all on the order of 10 ns. Finally, the feasibility of laser cooling of MgC1 molecule has been analyzed.展开更多
Yb^3+-doped new gallium-fluorophosphate glasses are prepared, and the influence of Ga2O3 on the physical properties, spectroscopic and lasing properties of yb^3+-doped fluorophosphate glasses was studied. The result...Yb^3+-doped new gallium-fluorophosphate glasses are prepared, and the influence of Ga2O3 on the physical properties, spectroscopic and lasing properties of yb^3+-doped fluorophosphate glasses was studied. The results show that the spectroscopic and lasing properties as well as crystallization stability of yb^3+-doped gallium-fluorophosphate glasses increase with the increasing amount of Ga2O3, fluorescence lifetime, emission cross-section and gain coefficient of yb^3+-doped gallium-fluorophosphate glasses reach the maximum values at Ga2O3%=8 mol%. The results indicate that yb^3+-doped gallium-fluorophosphate glasses can be as good candidate for ultra-short pulse lasers.展开更多
A new kind of Nd^3+-doped high silica glass (SiO2 〉 96% (mass fraction)) was obtained by sintering porous glass impregnated with Nd^3 + ions. The absorption and luminescence properties of high silica glass dope...A new kind of Nd^3+-doped high silica glass (SiO2 〉 96% (mass fraction)) was obtained by sintering porous glass impregnated with Nd^3 + ions. The absorption and luminescence properties of high silica glass doped with different Nd^3 + concentrations were studied. The intensity parameters Ωt (t = 2, 4, 6), spontaneous emission probability, fluorescence lifetime, radiative quantum efficiency, fluorescence branching ratio, and stimulated emission cross section were calculated using the Judd-Ofelt theory. The optimal Nd^3+ concentration in high silica glass was 0.27% (mole fraction) because of its high quantum efficiency and emission intensity. By comparing the spectroscopic parameters with other Nd^3 +- doped oxide glasses and commercial silicate glasses, the Nd^3 + -doped high silica glasses are likely to be a promising material used for high power and high repetition rate lasers.展开更多
基金the support from the National Natural Science Foundation of China (Grant Nos. 12074081 and 12104095)。
文摘Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics in fusion and astrophysical plasmas. In this work, we mainly focus on reviewing our two projects performed in the past decade. One is about the ions with Z■30 that are generally of astrophysical interest, and the other one is about the highly charged krypton(Z = 36)and tungsten(Z = 74) ions that are relevant in research of magnetic confinement fusion. Two different and independent methods, namely, multiconfiguration Dirac–Hartree–Fock(MCDHF) and the relativistic many-body perturbation theory(RMBPT) are usually used in our studies. As a complement/extension to our previous works for highly charged tungsten ions with open M-shell and open N-shell, we also mainly focus on presenting and discussing our complete RMBPT and MCDHF calculations for the excitation energies, wavelengths, electric dipole(E1), magnetic dipole(M1), electric quadrupole(E2), and magnetic quadrupole(M2) transition properties, and level lifetimes for the lowest 148 levels belonging to the 3l3configurations in Al-like W61+. We also summarize the uncertainties of our systematical theoretical calculations, by cross-checking/validating our datasets from our RMBPT and MCDHF calculations, and by detailed comparisons with available accurate observations and other theoretical calculations. The data are openly available in Science Data Bank at https://doi.org/10.57760/sciencedb.10569.
基金GVK Biosciences Pvt. Ltd., Hyderabad, India, for their assistance and support during this work
文摘Magnesium gluconate is a classical organometallic pharmaceutical compound used for the prevention and treatment of hypomagnesemia as a source of magnesium ion. The present research described the in-depth study on solid state properties viz. physicochemical and thermal properties of magnesium gluconate using sophisticated analytical techniques like Powder X-ray diffraction(PXRD), particle size analysis(PSA),Fourier transform infrared(FT-IR) spectrometry, ultraviolet–visible(UV–Vis) spectroscopy, thermogravimetric analysis(TGA)/differential thermogravimetric analysis(DTG), and differential scanning calorimetry(DSC).Magnesium gluconate was found to be crystalline in nature along with the crystallite size ranging from 14.10 to47.35 nm. The particle size distribution was at d(0.1)=6.552 μm, d(0.5)=38.299 μm, d(0.9)=173.712 μm and D(4,3)=67.122 μm along with the specific surface area of 0.372 m^2/g. The wavelength for the maximum absorbance was at 198.0 nm. Magnesium gluconate exhibited 88.51% weight loss with three stages of thermal degradation process up to 895.18 °C from room temperature. The TGA/DTG thermograms of the analyte indicated that magnesium gluconate was thermally stable up to around 165 °C. Consequently, the melting temperature of magnesium gluconate was found to be 169.90 °C along with the enthalpy of fusion of 308.7 J/g.Thus, the authors conclude that the achieved results from this study are very useful in pharmaceutical and nutraceutical industries for the identification, characterization and qualitative analysis of magnesium gluconate for preformulation studies and also for developing magnesium gluconate based novel formulation.
文摘Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of each energy levels for Er^(3+) were calculated by Judd-Ofelt theory, and stimulated emission cross-section of (()~4I_(13/2))→(()~4I_(15/2)) transition was calculated by McCumber theory. The results show that fluorescence full width at half maximum and stimulated emission cross-section of Er^(3+)-doped heavy metal oxyfluoride silicate glass are broad and large, respectively. Compared with other host glasses, the gain bandwidth property of Er^(3+)-doped heavy metal oxyfluoride silicate glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses.
基金supported by the National Natural Science Foundation of China (Grant Nos.61178056 and 60938001)the Hundred Talents Project of the Chinese Academy of Sciences
文摘The Er-single-doped and Er/Ce-codoped La3Ga5SiO14 polycrystalline powders are synthesized by the solid-phase synthesis method. The room-temperature luminescence spectra of the samples are investigated. The Near-infrared- region spectroscopic properties of Er3+ ions in the La3GasSiO14 systems are analysed with Judd-Ofelt theory and rate equations. The effective deactivating effect of Ce3+ ions on Er3+ ions is confirmed.
基金Supported by the Natural Science Foundation of Hunan Province(No.11JJ9006)Key Project of Science and Technology Plan of Hunan Province(2012FJ2002)the Construct Program of the Key Discipline in Hunan Province
文摘A new copper(Ⅱ) complex [Cu2(MNA)2(2,2‘-bipy)2]·2.5H2 O with methy-5-norbornene-2,3-dicarboxylic acid(MNA) and 2,2’-bipyridine as ligands has been synthesized in the mixed solvents of DMF and water.It crystallizes in monoclinic,space group P 1,with a = 10.4191(11),b = 12.8883(13),c = 16.1114(16) A,α = 70.8090(10),β = 80.568(2),γ = 77.440(2)o,V = 1984.3(4) A^3,Dc = 1.551 g/cm^3,Z = 2,F(000) = 962,the final GOOF = 1.051,R = 0.0431 and w R= 0.0980.The crystal structure shows that the whole molecule consists of two independent dinuclear units,in which two copper ions are bridged by two μ2-η^1:η^0 3-carboxylate groups of MNA^2-.The coordination environment of Cu(Ⅱ) ion is Cu O3N2,giving a distorted square pyramidal geometry.The spectroscopic characterization,thermal stability and magnetic properties of the complex were investigated.
基金Project supported bythe National Natural Science Foundation of Zhejiang Province (104498) ,the Foundation of Science andTechnology Bureau of Zhejiang Province (2005C31014 and 2006C21082)
文摘A series of novel Er^3+/Yb^3+ co-doped (85- x ) TeO2-15WO3-xB2O3 (TWB;x=2%,5%,8%(mole fraction) ) glasses were prepared. Influence of B203 on the spectroscopic properties of Er^3+/Yb^3+ co-doped tungsten-tellurite glasses were investigated. It is found that the intensity of 1.5μm fluorescence, lifetime of the ^4I13/2 level and upconversion fluorescence all decrease with the increase of B2O3 content. The product of full width at half maximum (FWHM) and stimulated emission cross-section (σe^peak) of Er^3+ :^4I13/2→^4I15/2 transition has an optimum when B203 is 5% (mole fraction). The emission spectra of Er^3+ : ^4I13/2→^4I15/2 transition was analyzed using peak-fit routine, and an equivalent four-level system was proposed to estimate the stark splitting for the 411512 and ^4I13/2 levels of Er^3+ ions in TWB glasses at room temperature.
基金Supported by the Science and Technology Research Project of Hubei Provincial Department of Education(China,No.Q20174302)the Scientific Research Foundation of Jingchu University of Technology(No.QN201602)National college students innovation and entrepreneurship training program(No.201811336003,China)
文摘Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-tolyl)-2,2′:6′,2″-terpyridine, salen = N,N?-ethylenebis-(salicylideneaminato)dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in orthorhombic Pbca space group and the asymmetric unit of 1 contains one[-NC-RuⅡ(ttpy)(CN)(m-CN)-Mn Ⅲ-(salen)-] molecule. In the structure of 1, each [Ru Ⅱ(ttpy)(CN)3]-connects two [MnⅢ(salen)]+ with two cyanide groups in a cis-conformation, and in turn each[MnⅢ(salen)]+ unit links two [RuⅡ(ttpy)(CN)3]-building blocks in a trans-conformation, resulting in a 1D [-NC-RuⅡ-CN-MnⅢ-]n chain. Furthermore, the electronic absorption spectra and luminescence spectroscopy of complex 1 have also been studied.
文摘This paper reports the growth, X-ray diffraction and spectroscopy of Nd3+:Sr3Gd2(BO3)4 crystal. A Nd3+:Sr3Gd2(BO3)4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3+:Sr3Gd2(BO3)4 crystal belongs to the orthorhombic system, space group Pnma (D2h) with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3+:Sr3Gd2(BO3)4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.
文摘This work is a contribution of theoretical chemistry to the classification of some non-steroidal anti-inflammatory drugs (NSAIDs). Indeed, research on the efficacy of NSAIDs has shown that no NSAID is recognized as the most efficient anti-inflammatory drug. We have made a theoretical study of diclofenac, bromfenac and amfenac, in order to compare their efficacy from some physicochemical properties. To do this, we used the DFT and TD-DTF methods at the B3LYP/6-311+G(d, p) level theory. The lipophilicity study shows that diclofenac and bromfenac are very lipophilic. Acidity study shows that diclofenac is more acid than bromfenac and amfenac. The results from molecular orbital and the TD-DFT calculations reveal that for the three NSAIDs, the lowest energy transition is due to the excitation from HOMO to LUMO. The absorption energy corresponding to H→L transition is comparable with the energy gap value. Our findings have shown that bromfenac is more reactive than amfenac, which is more reactive than diclofenac.
文摘The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.
文摘The syntheses of porphyrin-phthalocyanine heterodimers with flexible polyatomic chains especially designed for the studies of intramolecular photoinduced processes are presented along with the effect of mutual orientation of the chromophore subunits on intramolecular energy transfer efficiency.
基金supported by the National Natural Science Foundation of China(Grant Nos.61177086,61307046,and 61308086)the West Light Foundation of the Chinese Academy of Sciences(Grant No.Y129261213)
文摘A series of oxyfluoride glasses with the compositions of 75 mol% TeO2, 10 mol% Nb2O5, (15 mol%-x) BaO, x BaF2 (x =0 mol%, 5 mol%, 10 mol%, 15 mol%) doped with Yb2O3 were prepared by the melt-quenching method. Their emission cross-sections, fluorescence lifetimes, and gain properties were investigated by using the absorption spectra and the fluorescence decay curves. The results show that by substituting BaF2 for BaO, the emission cross-section decreases from 1.37 pm^2 to 1.21 pm^2, and the fluorescence lifetime increases from 0.71 ms to 0.96 ms. These properties indicate that this oxyfluoride tellurite glass may have potential uses as the Yb2O3-doped gain medium in a solid laser.
基金supported by the National Natural Science Foundation of China (Nos. 20774083, 20805024, and 20971075)the Foundation of the Education Department of Zhejiang Province (No. Y201016284)+2 种基金the Ningbo Municipal Natural Science Foundation (No. 2010A610146)the applied personnel training base construction project of Ningbo (No. Jd090104)the K. C. Wong Magna Fund in Ningbo University
文摘A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction of N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine with 2-fluoroiodobenzene (yield: 75%) and structurally characterized. It crystallizes in monoclinic, space group P21/n with a = 9.820(7), b = 14.305(11), c = 10.233(8) , β = 108.973(9)o, V = 1359.3(18) 3, Z = 2, Dc = 1.282 g/cm3, μ(MoKα) = 0.084 mm-1, F(000) = 548, S = 1.018, the final R = 0.0439 and wR = 0.0928. It presents a linear centrosymmetric framework constituted by a linkage of biphenyl as a bridge and two fluorinated diphenylamine moieties. The UV-Vis absorption and fluorescence spectra of the title compound were also investigated. This compound emits intense blue fluorescence with a peak wavelength of 406 nm in film.
文摘In order to develop a novel electric light source, the doped high-silica glass was studied on the preparation and spectroscopic properties. ne porous glasses were made firstly and were then immersed in the solution containing Ce ion. Thereafter, the high-silica glasses containing Ce ion were prepared by sintering the porous preform. The spectroscopic properties were studied before and after heath treatment in H-2. The experimental results indicate that the suitable temperature schedules are the most important to prepare doped high-silica glass. The study of the spectra shows that Ce ion can be reduced to low valence state when it is heat-treated in H-2. It can be used to adjust the UV cut-off wavelength of high-silica glass by changing the valence state of Ce ion.
文摘The Er^(3+)-doped TeO_2-WO_3-ZnO-ZnF_2(TWZOF) glasses were prepared. The absorption spectra, 1.5 μm emission spectra and fluorescence lifetimes of Er^(3+), excited at 970 nm, were measured. The J-O parameters Ω_ t (t =2, 4, 6), absorption and emission cross-sections were calculated. The dependence of the 1.5 μm emission intensity, fluorescence lifetime and bandwidth of the Er^(3+) emission upon the contents of ZnF_2 in glass were investigated. In TWZOF glass, Er^(3+) ions had a broad emission profile around 1.5 μm with the maximum FWHM of 83 nm. With the increasing of the content of ZnF_2, the emission intensity at peak wavelength and the fluorescence lifetime of Er^(3+) at 1.5 μm increase.
文摘The Nd^3+-doped pared. The absorption and tellurite glasses were preemission spectra of Nd^3 +- doped tellurite glasses at room temperature were measured. The Judd-Ofelt parameters (Ω2, Ω4, Ω6) of the glasses were calculated from measured absorption spectra. The calculation results of luminescence properties (A, β, τrad, σ) of Nd^3+ ions in the tellurite were glasses were given. Spectroscopic properties, concentration quenching in these kinds of the glasses were investigated. The results indicate that the tellurite glasses with composition of 70% TeO2, 20% ZnO, ( 10 - x ) % La2O3, x % Nd2O3 ( mol% ) show high emission cross section and low phonon energy. The fluorescent intensity and the emission cross section have a maxi- mum value at x = 0.5, namely, the optimum Nd^3 + ion concentration in the tellurite glass is 0.5% (1.93 × 10^20 ions·cm^-3). The fluorescence properties of Nd^3+ measured are basically in accord with the calculated results.
文摘A new serials of Er^3+/Yb^3+ co-doped tellurite-silicate glasses were prepared by the technique of high-temperature mehing. The thermal stability, absorption spectra, emission spectra and upconversion spectra were measured and investigated. It is found that these kinds of glasses have good thermal stability, broad FWHM and large stimulated emission cross-section. The three upconversion emission at 525, 546, 658 nm, corresponding to the ^2H11/2→^4Ⅰ15/2, ^4S3/2→4^Ⅰ15/2 and ^F9/2→^4Ⅰ15/2 transitions of Dr^3+ ions,
基金Project supported by the National Natural Science Foundation of China(Grand Nos.11564019,11147158,11264020,and 11574114)Jiangxi Provincial Education Department Project,China(Grand No.GJJ170654)
文摘The potential energy curves (PECs) of 14 A-S states for magnesium chloride (MgC1) have been calculated by using multi-reference configuration interaction method with Davidson correction (MRCI + Q). The core-valence correlation (CV), scalar relativistic effect, and spin-orbit coupling (SOC) effect are considered in the electronic structure computations. The spectroscopic constants of X2∑+ and A2П states have been obtained, which are in good agreement with the existing theoretical and experimental results. Furthermore, other higher electronic states are also characterized. The permanent dipole moments (PDMs) of A-S states and the spinorbit (SO) matrix elements between A-S states are also computed. The results indicate that the abrupt changes of PDMs and the SO matrix elements are attributed to the avoided crossing between the states with the same symmetry. The SOC effect is taken into account with Breit-Panli operator, which makes the 14 A-S states split into 30 Ωstates, and leads to a double-well potential of the Ω =(3)1/2 state. The energy splitting for the A2I-I is calculated to be 53.61 cm-1 and in good agreement with the experimental result 54.47 cm-1. The transition dipole moments (TDMs), Franck-Condon factors (FCFs), and the corresponding radiative lifetimes of the selected transitions from excited Ω states to the ground state X2∑+ 1/2 have been reported. The computed radiative lifetimes tV1, of low-lying excitesΩ states are all on the order of 10 ns. Finally, the feasibility of laser cooling of MgC1 molecule has been analyzed.
基金Funded by the Project of the National Nature Science Foundation of China (Nos.60508014 and 50502030)Program for New Century Excellent Talents in University (No.NCET-07-0786)
文摘Yb^3+-doped new gallium-fluorophosphate glasses are prepared, and the influence of Ga2O3 on the physical properties, spectroscopic and lasing properties of yb^3+-doped fluorophosphate glasses was studied. The results show that the spectroscopic and lasing properties as well as crystallization stability of yb^3+-doped gallium-fluorophosphate glasses increase with the increasing amount of Ga2O3, fluorescence lifetime, emission cross-section and gain coefficient of yb^3+-doped gallium-fluorophosphate glasses reach the maximum values at Ga2O3%=8 mol%. The results indicate that yb^3+-doped gallium-fluorophosphate glasses can be as good candidate for ultra-short pulse lasers.
基金Project supported bythe National Natural Science Foundation of China (50125258 and 60377040) ,the Shanghai Nano-TechPromote Center (0352nm042)
文摘A new kind of Nd^3+-doped high silica glass (SiO2 〉 96% (mass fraction)) was obtained by sintering porous glass impregnated with Nd^3 + ions. The absorption and luminescence properties of high silica glass doped with different Nd^3 + concentrations were studied. The intensity parameters Ωt (t = 2, 4, 6), spontaneous emission probability, fluorescence lifetime, radiative quantum efficiency, fluorescence branching ratio, and stimulated emission cross section were calculated using the Judd-Ofelt theory. The optimal Nd^3+ concentration in high silica glass was 0.27% (mole fraction) because of its high quantum efficiency and emission intensity. By comparing the spectroscopic parameters with other Nd^3 +- doped oxide glasses and commercial silicate glasses, the Nd^3 + -doped high silica glasses are likely to be a promising material used for high power and high repetition rate lasers.