The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to ...The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.展开更多
A new coordination polymer [Cu2(OH)(nbta)(tib)(H2 O)2]n(1, H3 nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, tib = 1-(4 H-1,2,4-triazol-4-yl)-4-(imidazol-1-yl)benzene) constructed from dimeric Cu(Ⅱ) units has been s...A new coordination polymer [Cu2(OH)(nbta)(tib)(H2 O)2]n(1, H3 nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, tib = 1-(4 H-1,2,4-triazol-4-yl)-4-(imidazol-1-yl)benzene) constructed from dimeric Cu(Ⅱ) units has been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction analysis. The compound crystallizes in monoclinic system, space group I2/c, with a = 17.8474(9), b = 11.7588(6), c = 21.9221(11) ?, β = 104.419(5)°, V = 4455.7(4) ?3 and Z = 8. Compound 1 is a three-dimensional structure constructed from dimeric Cu(Ⅱ) units and presents a 2-nodal(3,5)-connected net. Moreover, the thermal stability and solid UV-Vis absorption spectra have been investigated.展开更多
In this paper, the kind of remanent small molecules in unsaturated polyester res(?) (UP resin) , the best extractant and the best suitalbe extractive time for measuring the content of these small molecules were studie...In this paper, the kind of remanent small molecules in unsaturated polyester res(?) (UP resin) , the best extractant and the best suitalbe extractive time for measuring the content of these small molecules were studied using ultraviolet- visible spectrophotometry ( UV-VIS method). According to the principle of additivity lightness absorption for mixid solution, the contents of samll molecules in several kinds of cured UP resin were measured. It is pointed out that the UV-VIS method in the assay quality of food grade GRP products is more suitable to China.展开更多
The spin crossover(SCO) compound [Fe(bapbpy)(NCS)2],where bapbpy contains two fused N,N-bis(2-pyridyl)amines,has been studied by DFT/TD-DFT/BS-DFT methods.Several density functionals and basis sets were used i...The spin crossover(SCO) compound [Fe(bapbpy)(NCS)2],where bapbpy contains two fused N,N-bis(2-pyridyl)amines,has been studied by DFT/TD-DFT/BS-DFT methods.Several density functionals and basis sets were used in the calculation to obtain optimized geometries of the compound in the low-(LS) and high-spin(HS) states.The vibrational modes and IR spectra,spin splitting energies,excited states and UV/Vis absorption spectra were obtained.The structural parameters of the calculated isolated complex are in good agreement with the X-ray data.We investigate three dimers of [Fe(bapbpy)(NCS)2] complex for their magnetic properties.It has been found that the complex(1,3) has ferromagnetic character while the others are antiferromagnetic in nature by using a broken symmetry approach in the DFT framework(BS-DFT) with support from the coupling constant values(J) and spin density plots.展开更多
Surface morphology, compositions, microstructure and optical properties of GaN film irradiated by highly charged Kr^(q+)(q = 23, 15, 11) in two geometries to a fluence of 1×10^(15)kr^(q+)/cm^2 were studied using ...Surface morphology, compositions, microstructure and optical properties of GaN film irradiated by highly charged Kr^(q+)(q = 23, 15, 11) in two geometries to a fluence of 1×10^(15)kr^(q+)/cm^2 were studied using AFM,XPS, PL, Raman scattering and UV–visible spectroscopy.The AFM observation shows that the irradiated GaN area is a swollen terrace. The swelling rate increased with the charge state(potential energy). For the same charge state,the swelling rate of tilted incidence was greater than that for normal incidence. The XPS measurements reveal that N deficiency, Ga enrichment and Ga–O and Ga dangling bonds generated on the irradiated GaN surface increased with the charge state, and more N was lost for normal incidence than that for tilted incidence. The UV–Vis results show that the transmittance decreased with increasing charge state. For the same charge state, the transmittance for tilted incidence is higher than that for normal incidence.The PL spectra present that, with increasing charge state,the YL band intensity decreased, with a blueshift in its peak position; while the NBE peak intensity increased firstand then reduced, and a blue luminescence band appeared.A rapid quenching of both the YL and the NEB for normal incidence was observed. Raman spectra display that screw dislocations perhaps were produced near the surface for normal incidence.展开更多
Multivariate approaches like machine learning are commonly used in estimation of biochemical traits from spectral and color characteristics of foodstuffs and agricultural commodities.In present study,windfall apples o...Multivariate approaches like machine learning are commonly used in estimation of biochemical traits from spectral and color characteristics of foodstuffs and agricultural commodities.In present study,windfall apples of Golden Delicious,Oregon Spur and Granny Smith cultivars were dried in open-sun,controlled greenhouse,microwave oven(200W),hybrid system(100W+60℃),convective dryer(70℃)and freeze-dryer(−55℃).Spectral,chromatic and biochemical characteristics of dried apples were determined and assessed through machine learning algorithms.Total phenolic matter,DPPH(2,2-Diphenyl-1-picrylhydrazyl),FRAP(Ferric Reducing Antioxidant Power)and ascorbic acid content were estimated with the use of five different machine learning algorithms(artificial neural networks,k-nearest neighbor,random forest,gaussian processes and support vector regression).The most successful results were achieved in estimation of total phenolic content(R≥0.85).Additionally,Multilayer Perceptron,Support Vector Regression and Gaussian Processes were identified as the best machine learning algorithms in estimation of biochemical compositions of dried apples.展开更多
文摘The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.
基金supported by the National Natural Science Foundation of China(21401097)
文摘A new coordination polymer [Cu2(OH)(nbta)(tib)(H2 O)2]n(1, H3 nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, tib = 1-(4 H-1,2,4-triazol-4-yl)-4-(imidazol-1-yl)benzene) constructed from dimeric Cu(Ⅱ) units has been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction analysis. The compound crystallizes in monoclinic system, space group I2/c, with a = 17.8474(9), b = 11.7588(6), c = 21.9221(11) ?, β = 104.419(5)°, V = 4455.7(4) ?3 and Z = 8. Compound 1 is a three-dimensional structure constructed from dimeric Cu(Ⅱ) units and presents a 2-nodal(3,5)-connected net. Moreover, the thermal stability and solid UV-Vis absorption spectra have been investigated.
文摘In this paper, the kind of remanent small molecules in unsaturated polyester res(?) (UP resin) , the best extractant and the best suitalbe extractive time for measuring the content of these small molecules were studied using ultraviolet- visible spectrophotometry ( UV-VIS method). According to the principle of additivity lightness absorption for mixid solution, the contents of samll molecules in several kinds of cured UP resin were measured. It is pointed out that the UV-VIS method in the assay quality of food grade GRP products is more suitable to China.
基金Supported by the Natural Science Foundation of Shandong Province(No.Y2006B43)
文摘The spin crossover(SCO) compound [Fe(bapbpy)(NCS)2],where bapbpy contains two fused N,N-bis(2-pyridyl)amines,has been studied by DFT/TD-DFT/BS-DFT methods.Several density functionals and basis sets were used in the calculation to obtain optimized geometries of the compound in the low-(LS) and high-spin(HS) states.The vibrational modes and IR spectra,spin splitting energies,excited states and UV/Vis absorption spectra were obtained.The structural parameters of the calculated isolated complex are in good agreement with the X-ray data.We investigate three dimers of [Fe(bapbpy)(NCS)2] complex for their magnetic properties.It has been found that the complex(1,3) has ferromagnetic character while the others are antiferromagnetic in nature by using a broken symmetry approach in the DFT framework(BS-DFT) with support from the coupling constant values(J) and spin density plots.
基金supported by the National Natural Science Foundation of China(Nos.11675231,91426304 and 11105191)the National Magnetic Confinement Fusion Program(No.2011GB108003)the National Basic Research Program of China(No.2010CB832904)
文摘Surface morphology, compositions, microstructure and optical properties of GaN film irradiated by highly charged Kr^(q+)(q = 23, 15, 11) in two geometries to a fluence of 1×10^(15)kr^(q+)/cm^2 were studied using AFM,XPS, PL, Raman scattering and UV–visible spectroscopy.The AFM observation shows that the irradiated GaN area is a swollen terrace. The swelling rate increased with the charge state(potential energy). For the same charge state,the swelling rate of tilted incidence was greater than that for normal incidence. The XPS measurements reveal that N deficiency, Ga enrichment and Ga–O and Ga dangling bonds generated on the irradiated GaN surface increased with the charge state, and more N was lost for normal incidence than that for tilted incidence. The UV–Vis results show that the transmittance decreased with increasing charge state. For the same charge state, the transmittance for tilted incidence is higher than that for normal incidence.The PL spectra present that, with increasing charge state,the YL band intensity decreased, with a blueshift in its peak position; while the NBE peak intensity increased firstand then reduced, and a blue luminescence band appeared.A rapid quenching of both the YL and the NEB for normal incidence was observed. Raman spectra display that screw dislocations perhaps were produced near the surface for normal incidence.
基金grateful to Scientific Research Department of Erciyes University-Turkey for their financial support(Project no:FBA-2020-10157).
文摘Multivariate approaches like machine learning are commonly used in estimation of biochemical traits from spectral and color characteristics of foodstuffs and agricultural commodities.In present study,windfall apples of Golden Delicious,Oregon Spur and Granny Smith cultivars were dried in open-sun,controlled greenhouse,microwave oven(200W),hybrid system(100W+60℃),convective dryer(70℃)and freeze-dryer(−55℃).Spectral,chromatic and biochemical characteristics of dried apples were determined and assessed through machine learning algorithms.Total phenolic matter,DPPH(2,2-Diphenyl-1-picrylhydrazyl),FRAP(Ferric Reducing Antioxidant Power)and ascorbic acid content were estimated with the use of five different machine learning algorithms(artificial neural networks,k-nearest neighbor,random forest,gaussian processes and support vector regression).The most successful results were achieved in estimation of total phenolic content(R≥0.85).Additionally,Multilayer Perceptron,Support Vector Regression and Gaussian Processes were identified as the best machine learning algorithms in estimation of biochemical compositions of dried apples.