An atlas of high resolution （R = 60 000） CCD-spectra in the wavelength range 3500-5000A is presented for four objects in metallicity range -3.0 〈 [Fe/H] 〈 -0.6, temperature range 4750 〈 Teff 〈 5900K, and surface...An atlas of high resolution （R = 60 000） CCD-spectra in the wavelength range 3500-5000A is presented for four objects in metallicity range -3.0 〈 [Fe/H] 〈 -0.6, temperature range 4750 〈 Teff 〈 5900K, and surface gravity range 1.6 〈 Igg 〈 5.0. We describe the calibration of the stellar atmospheric parameters using Alonso＇s formula based on the method of infrared flux and outline the determination of the abundances of a total number of 25 chemical elements. An analysis of the abundance determination errors for different chemical elements is carried out, and a method is provided for the observations and reduction of spectral material. Properties of the method of producing an atlas of spectra and line identifications are described.展开更多
Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has bee...Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3);b(?) 12.446(3);c(?) 13.716(3);(o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2)?? and from 1.292(2) to 1.293?? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I.展开更多
A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ...A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.展开更多
Optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-（4- ethoxyphenyl）thiophene （C16Hj2N2OS） are calculated at the HF/6-31＋＋G（d,p） and B3LYP/6- 311 ＋＋G（d,p） levels. Mulliken charges in...Optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-（4- ethoxyphenyl）thiophene （C16Hj2N2OS） are calculated at the HF/6-31＋＋G（d,p） and B3LYP/6- 311 ＋＋G（d,p） levels. Mulliken charges in the ground state are also calculated. The research shows the presence of intermolecular interaction in the title compound. The scaled harmonic vibrational frequencies have been compared with experimental FT-IR spectra. A detailed interpretation of the infrared spectra of the title compound is reported. The theoretical spectrograms for IR spectra of the title compound have been constructed, The isotropic chemical shift computed by 13C and 1H NMR analyses also shows good agreement with the experimental observations.展开更多
We have prepared the 2-（quinolin-8-yloxy）-acetic acid and characterized it by infrared and Raman spectroscopies in the solid phase. The Density Functional Theory （DFT） method, together with the 6-31G^＊ and 6-311...We have prepared the 2-（quinolin-8-yloxy）-acetic acid and characterized it by infrared and Raman spectroscopies in the solid phase. The Density Functional Theory （DFT） method, together with the 6-31G^＊ and 6-311＋＋ G^＊＊ basis sets, show that three stable molecules, for the anhydrous and monohydrated compounds were theoretically determined in the gas phase, and that probably the two more stable conformations are present in the solid phase of the monohydrated compound. The harmonic vibrational wavenumbers for the optimized geometries were calculated at B3LYP/6-31G^＊and B3LYP/6-311＋＋G^＊＊ levels. For a complete assignment of all the observed bands in the vibrational spectra the DFT calculations were combined with Pulay＇s scaled quantum mechanical force field （SQMFF） methodology in order to fit the theoretical Wavenumber values to the experimental ones. The characteristics of the electronic delocalization of all structures of both forms were performed by using natural bond orbital （NBO）, while the corresponding topological properties of electronic charge density are analysed by employing Bader＇s atoms in molecules theory （AIM）.展开更多
We investigate the global properties of X-ray emission from O stars, analyzing the X-ray spec- tra of 32 O stars from archival data of the XMM-Newton space observatory. We examine two hypotheses about of the origin of...We investigate the global properties of X-ray emission from O stars, analyzing the X-ray spec- tra of 32 O stars from archival data of the XMM-Newton space observatory. We examine two hypotheses about of the origin of X-ray emission from O stars. The first is a paradigm proposed by Pollock, that was revealed from an analysis of the （ Ori X-ray observation. The second is the magnetically confined wind-shock （MCWS） model. For checking Pollock＇s hypothesis, we determine the distribution of the ratio of half width at half maximum （HWHM） to the wind terminal velocity for lines in spectra of all examined stars. In addition, we check three probable consequences from the MCWS model. We analyze if a correlation exists between the spectral hardness and such stellar parameters as the wind terminal velocity, stellar magnetic field and mass loss rate. The result showed that Pollock＇s hypothesis is not correct. We also established that not all consequences of the MCWS model considered by us are con- firmed. In addition, our spectral analysis method indicated that O stars probably have clumped stellar winds with spherical clumps.展开更多
In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and g...In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and generalizes the results of Mursaleen et al. [1]. At the end, we will provide an example in support of our result.展开更多
Geometry optimization and subsequent harmonic vibration calculations of prior synthesized （E）-3-（4-fluorophenyl）-N-[4-（phenyl-amino） quinazoline-7-yl] acrylamide were carried out by DFT/B3LYP method with both 6-...Geometry optimization and subsequent harmonic vibration calculations of prior synthesized （E）-3-（4-fluorophenyl）-N-[4-（phenyl-amino） quinazoline-7-yl] acrylamide were carried out by DFT/B3LYP method with both 6-31G and 6-311G basis sets.The Infrared （IR） spectrum of the title compound was recorded in the field of 400-4000 cm 1 and then assigned.The correlation analyses between the scaled theoretical vibration frequencies and the experimental ones indicate that there exist good linearity relationships since the correlation coefficients R 2 are larger than 0.999.The intramolecular interactions existed in the title molecule were confirmed by the Atoms in molecules （AIM） method,and their influences on the absorption frequency were also investigated.展开更多
The decay of the neutron-rich erbium isotope <sup>175</sup>Er is studied by using the reaction<sup>176</sup>Yb（n,2p）<sup>175</sup>Er.A partial decay scheme is proposed on the basi...The decay of the neutron-rich erbium isotope <sup>175</sup>Er is studied by using the reaction<sup>176</sup>Yb（n,2p）<sup>175</sup>Er.A partial decay scheme is proposed on the basis of X-γ and γ-γ coincidencemeasurements,taking into account eight observed gamma rays.A ground rotational band is as-signed to <sup>175</sup>Tm.Some systematic behaviors of 1/2+[411] ground rotational bands in odd-Athulium are described.The experimental and calculated decoupling parameters of these bandsare compared.展开更多
The high-spin states in <sup>197</sup>Bi are studied with the <sup>197</sup>Re(<sup>16</sup>O, 6n) reaction, theenergies of <sup>16</sup>O being between 85 and 105 MeV. ...The high-spin states in <sup>197</sup>Bi are studied with the <sup>197</sup>Re(<sup>16</sup>O, 6n) reaction, theenergies of <sup>16</sup>O being between 85 and 105 MeV. In-beam measurements of γ-ray excitation func-tions, γ-γ-t coincidences and γ-ray angular distributions are performed with six BGO （AC）HPGe detectors and one intrinsic Ge planar detector. Eleven new transitions and three new iso-mers at 2089, 2357 and 1968+△keV with T<sub>1/2</sub>=19, 34±4, 9, 53, 4±20. 5 and 18. 04±3. 1 ns,respectively, are observed, and a level scheme established. In addition, a half-life of 36. 7±7.0 ns was determined for the first time for the previously established 2065 keV isomer.展开更多
An accurate energy calibration of a BC501A liquid scintillator by means of Compton scattering of γ-rays is described.The energy resolution and the position of the Compton edge have been precisely determined using a ...An accurate energy calibration of a BC501A liquid scintillator by means of Compton scattering of γ-rays is described.The energy resolution and the position of the Compton edge have been precisely determined using a γ-γ coincidence technique and fitting the coincidence spectrum with a Gaussian function superimposed on a quadratic polynomial for the background.The position of the Compton edge relative to the position of the maximum and the half height of the distribution in dependence on the relevant energy resolution is discussed in detail.The results indicate that the maximum energy of the recoil Compton electron does not occur at the half height distribution but at 0.90±0.05 of the maximum height in the energy range considered.The energy resolution varies from 15.6% to 8.02% for electrons in the energy region from 0.5 MeV to 3 MeV.展开更多
The X ray diffraction spectra and X ray photoelectron spectroscopy were measured for Sr doped La 1- x Sr x CoO 3 materials with perovskite structure prepared by the solid state reaction method. The in...The X ray diffraction spectra and X ray photoelectron spectroscopy were measured for Sr doped La 1- x Sr x CoO 3 materials with perovskite structure prepared by the solid state reaction method. The influence of heat treatment temperature on the average crystal size of La 1- x Sr x CoO 3 was studied. The surface chemical states of La 1- x Sr x CoO 3 cathodes with different Sr doped content were discussed. The experimental results show that average crystal size of La 1- x Sr x CoO 3 under the condition of heat treatment in the range of 900～1200 ℃ is larger than that at other temperatures, which is of benefit to forming porous electrodes. When La is replaced by Sr gradually, the oxygen vacancy concentration increases. It is of benefit to enhancing the transport property of oxygen ion.展开更多
基金Supported by the National Natural Science Foundation of China.
文摘An atlas of high resolution （R = 60 000） CCD-spectra in the wavelength range 3500-5000A is presented for four objects in metallicity range -3.0 〈 [Fe/H] 〈 -0.6, temperature range 4750 〈 Teff 〈 5900K, and surface gravity range 1.6 〈 Igg 〈 5.0. We describe the calibration of the stellar atmospheric parameters using Alonso＇s formula based on the method of infrared flux and outline the determination of the abundances of a total number of 25 chemical elements. An analysis of the abundance determination errors for different chemical elements is carried out, and a method is provided for the observations and reduction of spectral material. Properties of the method of producing an atlas of spectra and line identifications are described.
文摘Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3);b(?) 12.446(3);c(?) 13.716(3);(o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2)?? and from 1.292(2) to 1.293?? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I.
基金Supported by the Scientific Research Foundation of Higher Education Institutions of Ningxia(No.NGY2017004)the National Natural Science Foundation of China(Nos.21763022 and 50564043)the Major Innovation Projects for Building First-class Universities in China’s Western Region(No.ZKZD2017003)
文摘A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.
基金Supported by the National Natural Science Foundation of China (No. 10774039)the key project of Henan Educational Committee (No. 12A140004)Henan University of Science and Technology for Young Scholars (No. 2009QN0032)
文摘Optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-（4- ethoxyphenyl）thiophene （C16Hj2N2OS） are calculated at the HF/6-31＋＋G（d,p） and B3LYP/6- 311 ＋＋G（d,p） levels. Mulliken charges in the ground state are also calculated. The research shows the presence of intermolecular interaction in the title compound. The scaled harmonic vibrational frequencies have been compared with experimental FT-IR spectra. A detailed interpretation of the infrared spectra of the title compound is reported. The theoretical spectrograms for IR spectra of the title compound have been constructed, The isotropic chemical shift computed by 13C and 1H NMR analyses also shows good agreement with the experimental observations.
文摘We have prepared the 2-（quinolin-8-yloxy）-acetic acid and characterized it by infrared and Raman spectroscopies in the solid phase. The Density Functional Theory （DFT） method, together with the 6-31G^＊ and 6-311＋＋ G^＊＊ basis sets, show that three stable molecules, for the anhydrous and monohydrated compounds were theoretically determined in the gas phase, and that probably the two more stable conformations are present in the solid phase of the monohydrated compound. The harmonic vibrational wavenumbers for the optimized geometries were calculated at B3LYP/6-31G^＊and B3LYP/6-311＋＋G^＊＊ levels. For a complete assignment of all the observed bands in the vibrational spectra the DFT calculations were combined with Pulay＇s scaled quantum mechanical force field （SQMFF） methodology in order to fit the theoretical Wavenumber values to the experimental ones. The characteristics of the electronic delocalization of all structures of both forms were performed by using natural bond orbital （NBO）, while the corresponding topological properties of electronic charge density are analysed by employing Bader＇s atoms in molecules theory （AIM）.
基金support from the Russian Science Foundation project No.18-12-00423RFBR grant 18-02-00554
文摘We investigate the global properties of X-ray emission from O stars, analyzing the X-ray spec- tra of 32 O stars from archival data of the XMM-Newton space observatory. We examine two hypotheses about of the origin of X-ray emission from O stars. The first is a paradigm proposed by Pollock, that was revealed from an analysis of the （ Ori X-ray observation. The second is the magnetically confined wind-shock （MCWS） model. For checking Pollock＇s hypothesis, we determine the distribution of the ratio of half width at half maximum （HWHM） to the wind terminal velocity for lines in spectra of all examined stars. In addition, we check three probable consequences from the MCWS model. We analyze if a correlation exists between the spectral hardness and such stellar parameters as the wind terminal velocity, stellar magnetic field and mass loss rate. The result showed that Pollock＇s hypothesis is not correct. We also established that not all consequences of the MCWS model considered by us are con- firmed. In addition, our spectral analysis method indicated that O stars probably have clumped stellar winds with spherical clumps.
文摘In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and generalizes the results of Mursaleen et al. [1]. At the end, we will provide an example in support of our result.
文摘Geometry optimization and subsequent harmonic vibration calculations of prior synthesized （E）-3-（4-fluorophenyl）-N-[4-（phenyl-amino） quinazoline-7-yl] acrylamide were carried out by DFT/B3LYP method with both 6-31G and 6-311G basis sets.The Infrared （IR） spectrum of the title compound was recorded in the field of 400-4000 cm 1 and then assigned.The correlation analyses between the scaled theoretical vibration frequencies and the experimental ones indicate that there exist good linearity relationships since the correlation coefficients R 2 are larger than 0.999.The intramolecular interactions existed in the title molecule were confirmed by the Atoms in molecules （AIM） method,and their influences on the absorption frequency were also investigated.
基金The project supported by the National Natural Scierice Foundation of Chinathe Chinose Academy of Sciences
文摘The decay of the neutron-rich erbium isotope <sup>175</sup>Er is studied by using the reaction<sup>176</sup>Yb（n,2p）<sup>175</sup>Er.A partial decay scheme is proposed on the basis of X-γ and γ-γ coincidencemeasurements,taking into account eight observed gamma rays.A ground rotational band is as-signed to <sup>175</sup>Tm.Some systematic behaviors of 1/2+[411] ground rotational bands in odd-Athulium are described.The experimental and calculated decoupling parameters of these bandsare compared.
文摘The high-spin states in <sup>197</sup>Bi are studied with the <sup>197</sup>Re(<sup>16</sup>O, 6n) reaction, theenergies of <sup>16</sup>O being between 85 and 105 MeV. In-beam measurements of γ-ray excitation func-tions, γ-γ-t coincidences and γ-ray angular distributions are performed with six BGO （AC）HPGe detectors and one intrinsic Ge planar detector. Eleven new transitions and three new iso-mers at 2089, 2357 and 1968+△keV with T<sub>1/2</sub>=19, 34±4, 9, 53, 4±20. 5 and 18. 04±3. 1 ns,respectively, are observed, and a level scheme established. In addition, a half-life of 36. 7±7.0 ns was determined for the first time for the previously established 2065 keV isomer.
文摘An accurate energy calibration of a BC501A liquid scintillator by means of Compton scattering of γ-rays is described.The energy resolution and the position of the Compton edge have been precisely determined using a γ-γ coincidence technique and fitting the coincidence spectrum with a Gaussian function superimposed on a quadratic polynomial for the background.The position of the Compton edge relative to the position of the maximum and the half height of the distribution in dependence on the relevant energy resolution is discussed in detail.The results indicate that the maximum energy of the recoil Compton electron does not occur at the half height distribution but at 0.90±0.05 of the maximum height in the energy range considered.The energy resolution varies from 15.6% to 8.02% for electrons in the energy region from 0.5 MeV to 3 MeV.
文摘The X ray diffraction spectra and X ray photoelectron spectroscopy were measured for Sr doped La 1- x Sr x CoO 3 materials with perovskite structure prepared by the solid state reaction method. The influence of heat treatment temperature on the average crystal size of La 1- x Sr x CoO 3 was studied. The surface chemical states of La 1- x Sr x CoO 3 cathodes with different Sr doped content were discussed. The experimental results show that average crystal size of La 1- x Sr x CoO 3 under the condition of heat treatment in the range of 900～1200 ℃ is larger than that at other temperatures, which is of benefit to forming porous electrodes. When La is replaced by Sr gradually, the oxygen vacancy concentration increases. It is of benefit to enhancing the transport property of oxygen ion.
