The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the...The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the UV-visible spectra of thin fihn of CuCl2/H2O solutions at different concentrations. This method is the combination of ratio spectra, difference spectra and second order difference spectra. By using this method, two new bands at -230 and -380 nm are obviously observed. The bands are assigned as the contacted ion pairs [CuCl3(H2O)n]- or [CuCl4(H2O)n]2-, which demonstrates that ion pairs exist in the CuCl2/H2O solution. Such finding agrees with the recent theoretical spectra obtained by time-dependent density functional theory. Furthermore, the populations of the contacted ion pairs are discussed. This study not only offers the direct spectroscopic evidence of [CuCl3(H2O)n]- or [CuCl4(H2O)n]2- in aqueous CuCl2, but also suggests that the spec- troscopic analysis method is powerful to extract the weak bands in a strong overlapping spectrum.展开更多
Rare earth sulfides were systematically synthesized via the sulfurization of their commercial oxide powders using CS2 gas to shorten sulfurization time, and their UV-vis absorption spectra were investigated. The appro...Rare earth sulfides were systematically synthesized via the sulfurization of their commercial oxide powders using CS2 gas to shorten sulfurization time, and their UV-vis absorption spectra were investigated. The appropriate sulfurization conditions were studied. For the rare earth sulfides with the same crystal structure, the sulfurization temperature showed increasing tendency with the decrease of rare earth element atomic radii. The UV-vis absorption spectra of rare earth sulfides did not depend on the crystal structure of rare earth sulfides, but on the 4f electronic structure of rare earth element. The data showed that the optical band gaps of rare earth sulfides were irregular, and the values ranged from 1.65 to 3.75 eV.展开更多
The electrocatalytic oxidation of hypophosphite on a nickel electrode has been studiedby means of in site UV-Vis subtractive reflectance spectroscopy. An absorbency band around 245um . which was ascribed to the format...The electrocatalytic oxidation of hypophosphite on a nickel electrode has been studiedby means of in site UV-Vis subtractive reflectance spectroscopy. An absorbency band around 245um . which was ascribed to the formation of an intermediate, PHO2-, was observed in theelectrocatalytic oxidation process. Accordingly, the electrocatalytic oxidation of hypophosphitemight undergo a H abstraction of hypophosphite from the P-H bond to form the phosphoruscentred radical PHO2-, which is subsequently electrooxidized to the final product, phosphite.展开更多
The interactions of 4-aminosalicylic acid (4-ASA) and surfactants in aqueous solutions were investigated by using UV-Vis spectra and steady-state fluorescence spectroscopy.The results showed that the strongest peak ...The interactions of 4-aminosalicylic acid (4-ASA) and surfactants in aqueous solutions were investigated by using UV-Vis spectra and steady-state fluorescence spectroscopy.The results showed that the strongest peak at UV-vis spectra of 4-ASA aqueous solution in the presence of cationic surfactant and cetyltrimethyl ammonium bromide (CTAB) appeared at 206 nm and took a red shift from 206 nm to 221 nm with the increase of 4-ASA concentrations from 0.8×10-5 to 4.4×10-4 mol/L.Similarly,the strongest peak at UV-vis spectra of 4-ASA aqueous solution in the presence of nonionic surfactant and polyvinylpyrrolidone (PVP) appeared at 206 nm and took a red shift from 206 nm to 219 nm with the increase of 4-ASA concentrations from 0.8×10-5 to 4.4×10-4 mol/L.However,the similar phenomena did not appeared in the presence of anion surfactant,sodium dodecyl sulfate (SDS),the UV-vis spectra of 4-ASA aqueous solution remained the same peak position and the peak value increased with the 4-ASA concentration increase.The results could be attributed to the electrostatic attraction between 4-ASA and CTAB or PVP,as well as the electrostatic repulsion between 4-ASA and SDS.Furthermore,the value of critical micelle concentration (CMC) of surfactants in the presence of 4-ASA was determined with Fluorescence method.The first and second CMC of CTAB was 1.2×10-4 M and 2.4×10-4 M,respectively.The first and second CMC of PVP was 1.2×10-4 M and 2.8×10-4 M.SDS realized the multiple micellizations to form multiple CMC.展开更多
This paper is devoted to the study of the potentiality of the Fricke dosimeter for the characterization of the highly energetic (62.1 MeV) α particles beams generated by a new cyclotron facility, namely ARRONAX start...This paper is devoted to the study of the potentiality of the Fricke dosimeter for the characterization of the highly energetic (62.1 MeV) α particles beams generated by a new cyclotron facility, namely ARRONAX started in 2009. Such for this high energetic α beam, in situ dosimetry is performed in order to avoid radiation safety inconvenience and to earn run time of irradiation. Therefore, an in situ Fricke dosimetry protocol is developed and its reliability is checked by comparison with other experiments carried out by using the traditional method (ex situ Fricke dosimetry) within another cyclotron facility (CEMHTI) and by comparison with literature data. To author’s knowledge, it is the first time that Fricke dosimetry is performed during the α irradiation experiment. The results of these in situ dosimetry experiments show that the value of ferric ions radiolytic yield (G(Fe3+) = (11.7 ± 1.2) 10–7 mol?J–1) extrapolated from literature data can be used for this higher energy of α particles (Eα = 62.1 MeV).展开更多
Chinese liquor Moutai is the “National alcoholic drink” in China and plays a very important role of social activities in Chinese people’s life. In pursuit of high profits, some illegal counterfeit Moutai liquors ha...Chinese liquor Moutai is the “National alcoholic drink” in China and plays a very important role of social activities in Chinese people’s life. In pursuit of high profits, some illegal counterfeit Moutai liquors have begun to appear in the market. Therefore, it is an urgent need for new techniques to discriminate the genuine and counterfeit Moutai liquor. In this work, the conventional Ultraviolet-Visible (UV-Vis) spectroscopy and two-dimensional correlation UV-Vis spectroscopy are applied to obtain the UV-Vis characteristic of Moutai liquor and counterfeit one, respectively. The experimental results reveal that the conventional UV-Vis spectra of the genuine and counterfeit Moutai liquor are similar. However, the two-dimensional correlation UV-Vis spectra of them are different and this method would be applied to differentiate the counterfeit Moutai liquor from the genuine Moutai liquor. Compared with conventional methods, this novel method has the advantages of easy operation, simple instrumentation and direct recognition, which make it a potential tool in the fields of food safety.展开更多
Reactive bright blue rare earth dyestuffs were prepared by using reactive bright blue and lanthanum oxide,praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, erbium...Reactive bright blue rare earth dyestuffs were prepared by using reactive bright blue and lanthanum oxide,praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, erbium oxide, lutetium oxide, yttrium oxide respectively for dyeing silk cloth.The degree of dyeing of reactive bright blue praseodymium and the degree of fixation of reactive bright blue gadolinium are the biggest, and 22.9% and 7 %are increased with that of reactive bright blue respectively.The spectra of reactive bright blue rare earth and reactive bright blue were studied by UV-VIS.In 200.00 ~ 800.00 nm, reactive bright blue has four absorption peaks, reactive bright blue rare earth has three absorption peaks; in 420.00 ~ 760.00 nm, reactive bright blue has two absorption peaks at 661.50 nm and 625.50 nm, respectively, and λmax is 661.50 nm; reactive bright blue rare earth has one absorption peak at 620.50, 618.00, 622.00, 623.00, 622.50, 619.50, 619.00, 621.00, 624.00, 620.00 nm adding La3+ ,Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Er3+, Lu3+, Y3+respectively.展开更多
The investigation on UV-visible spectra of species formed by extracting some metal picrates with benzo-15-crown-5(B15C5) and dibenzo-18-crown-6(DB18C6) verified that there are some interactions of picrate anion with K...The investigation on UV-visible spectra of species formed by extracting some metal picrates with benzo-15-crown-5(B15C5) and dibenzo-18-crown-6(DB18C6) verified that there are some interactions of picrate anion with K+, Na+ and rare earth ions in loaded organic phase. By the study of the charge transfer band and absorption spectra of picrate anion, it can be determined whether an ion pair has been formed and either a 1 : 1 contact ion pair or a 1 : 2 crown-separated ion pair involved in organic phase can be distinguished for an ion-pair extraction.展开更多
Being widely used as good ligands,xanthates and related compounds have been extensively investigated.However,reports on Pt(Ⅱ) xanthates have been sparse so far.Watt et al.reported the synthesis and characterization...Being widely used as good ligands,xanthates and related compounds have been extensively investigated.However,reports on Pt(Ⅱ) xanthates have been sparse so far.Watt et al.reported the synthesis and characterization of Pt(S;COR);(R=Me,Et),but did not provide any absorption spectra of these complexes.We prepared twelve platinum (Ⅱ) xanthate complexes and examined their absorption spectra in detail.展开更多
The effect of laser energy density on the crystallization of hydrogenated intrinsic amorphous silicon (a-Si:H) thin films was studied both theoretically and experimentally. The thin films were irritated by a freque...The effect of laser energy density on the crystallization of hydrogenated intrinsic amorphous silicon (a-Si:H) thin films was studied both theoretically and experimentally. The thin films were irritated by a frequency-doubled (λ= 532 nm) Nd:YAG pulsed nanosecond laser. An effective density functional theory model was built to reveal the variation of bandgap energy influenced by thermal stress after laser irradiation. Experimental results establish correlation between the thermal stress and the shift of transverse optical peak in Raman spectroscopy and suggest that the relatively greater shift of the transverse optical (TO) peak can produce higher stress. The highest crystalline fraction (84.5%) is obtained in the optimized laser energy density (1000 mJ/cm2) with a considerable stress release. The absorption edge energy measured by the UV- visible spectra is in fairly good agreement with the bandgap energy in the density functional theory (DFT) simulation.展开更多
Reactive blue rare earth dyestuffs were prepared by using reactive blue and lanthanum oxide, praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, terbium oxide, dysprosium oxide, erbi...Reactive blue rare earth dyestuffs were prepared by using reactive blue and lanthanum oxide, praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, terbium oxide, dysprosium oxide, erbium oxide, lutetium oxide and yttrium oxide respectively for dyeing silk cloth. The degrees of dyeing of reactive blue gadolinium and fixation of reactive blue neodymium were the biggest respectively, were 84.83% and 97.96 respectively, were 24.13% and 8.36% were increased with that of reactive blue respectively. The spectra of reactive blue rare earths and reactive blue were studied by UV-VIS. In 200.00~800.00 nm, the λmax of reactive blue, reactive blue lanthanum, reactive blue praseodymium, reactive blue neodymium, reactive blue samarium, reactive blue europium, reactive blue gadolinium, reactive blue terbium, reactive blue dysprosium, reactive blue erbium, reactive blue lutetium and reactive blue yttrium are 599.00, 600.00, 602.00, 601.00, 600.00, 600.50, 600.50, 601.00, 600.00, 600.50, 599.50 and 600.50 nm respectively. Reactive blue lanthanum, reactive blue praseodymium, reactive blue neodymium, reactive blue samarium, reactive blue europium, reactive blue gadolinium, reactive blue terbium, reactive blue dysprosium, reactive blue erbium, reactive blue lutetium, reactive blue yttrium and reactive blue had almost same color.展开更多
A bis-2-iminopyrrole compound(1) and its difluoroboron complex(2) were synthesized and characterized. The crystal of 2 is in the monoclinic system, P2_1/n space group with a = 21.5113(15), b = 6.3036(3), c = 2...A bis-2-iminopyrrole compound(1) and its difluoroboron complex(2) were synthesized and characterized. The crystal of 2 is in the monoclinic system, P2_1/n space group with a = 21.5113(15), b = 6.3036(3), c = 21.5064(15) A, V = 2826.3(7) A^3, Z = 4, C_(26.5) H_(25) B_2 ClF_4 N_4 O, M_r = 548.57, D_c = 1.390 g/cm, F(000) = 1132 and μ(MoKα) = 1.787 mm^-1. The final R = 0.0647 and wR = 0.1817 for 10346 observed reflections with I 〉 2σ(I), and R = 0.0889 and wR = 0.1993 for all data. The molecules of complex 2 self-assemble through C–H×××F hydrogen bonds and form tubular structures which are filled by CH_2 Cl_2 molecules stabilized by C–H×××π interaction. The UV-Vis spectra of complex 2 show great bathochromic shift compared to that of compound 1 due to the difluoroboron complexing. Complex 2 shows fluorescence emission both in solid state and in solution, whereas compound 1 only exhibits fluorescence emission in solid state.展开更多
The in situ ultraviolet-visible (UV-Vis) spectroelectrochemical study on the copolymerization of diphenylamine (DPA) and o-phenylenediamine (OPD) has been performed at a constant potential of 0.8 V using indium tin ox...The in situ ultraviolet-visible (UV-Vis) spectroelectrochemical study on the copolymerization of diphenylamine (DPA) and o-phenylenediamine (OPD) has been performed at a constant potential of 0.8 V using indium tin oxide (ITO)-coated glass electrodes as working electrode. And also, as a comparison, the electrochemical homopolymerizations of DPA and OPD have been investigated by using the in situ spectroelectrochemical technique. The intermediate species generated during the electrochemical homopoly-merization of DPA and OPD, and the copolymerization of DPA with OPD have been identified by using the in situ spectroelectrochemical procedure. The results reveal the formation of an intermediate in the initial stage of copolymerization through the cross-reaction of the cation radicals of DPA and OPD, and the absorption peak located at 538 nm in the UV–Vis spectra is assigned to this intermediate. To further investigate the copolymerization of DPA with OPD, cyclic voltammetry (CV) has been used to study the electrochemical homopolymerization of DPA and OPD and also the copolymerization of DPA and OPD with different concentration ratios in solution. The different voltammetric characteristics between the homopolymerization and copolymerization processes exhibit the occurrence of the copolymerization, and the difference between the copolymerization of DPA and OPD with different concentration ratios shows the dependence of the copoly-merization on the concentrations of DPA and OPD. The copolymer has also been characterized by Fourier transform infrared spectroscopy (FT-IR).展开更多
The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of...The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process.展开更多
AlPO 4 5 molecular sieve with an orthorhombic phase was studied by in situ variable temperature infrared spectroscopy. The reversible phase transition from the orthorhombic into the hexagonal phase was found at about ...AlPO 4 5 molecular sieve with an orthorhombic phase was studied by in situ variable temperature infrared spectroscopy. The reversible phase transition from the orthorhombic into the hexagonal phase was found at about 120 ℃. [WT5HZ]展开更多
文摘The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the UV-visible spectra of thin fihn of CuCl2/H2O solutions at different concentrations. This method is the combination of ratio spectra, difference spectra and second order difference spectra. By using this method, two new bands at -230 and -380 nm are obviously observed. The bands are assigned as the contacted ion pairs [CuCl3(H2O)n]- or [CuCl4(H2O)n]2-, which demonstrates that ion pairs exist in the CuCl2/H2O solution. Such finding agrees with the recent theoretical spectra obtained by time-dependent density functional theory. Furthermore, the populations of the contacted ion pairs are discussed. This study not only offers the direct spectroscopic evidence of [CuCl3(H2O)n]- or [CuCl4(H2O)n]2- in aqueous CuCl2, but also suggests that the spec- troscopic analysis method is powerful to extract the weak bands in a strong overlapping spectrum.
基金supported by the National Natural Science Foundation of China (20501023)the Natural Science Foundation of Guangdong for Doctorial Training Base (5300527)
文摘Rare earth sulfides were systematically synthesized via the sulfurization of their commercial oxide powders using CS2 gas to shorten sulfurization time, and their UV-vis absorption spectra were investigated. The appropriate sulfurization conditions were studied. For the rare earth sulfides with the same crystal structure, the sulfurization temperature showed increasing tendency with the decrease of rare earth element atomic radii. The UV-vis absorption spectra of rare earth sulfides did not depend on the crystal structure of rare earth sulfides, but on the 4f electronic structure of rare earth element. The data showed that the optical band gaps of rare earth sulfides were irregular, and the values ranged from 1.65 to 3.75 eV.
文摘The electrocatalytic oxidation of hypophosphite on a nickel electrode has been studiedby means of in site UV-Vis subtractive reflectance spectroscopy. An absorbency band around 245um . which was ascribed to the formation of an intermediate, PHO2-, was observed in theelectrocatalytic oxidation process. Accordingly, the electrocatalytic oxidation of hypophosphitemight undergo a H abstraction of hypophosphite from the P-H bond to form the phosphoruscentred radical PHO2-, which is subsequently electrooxidized to the final product, phosphite.
基金Funded by the Foundation of Key Laboratory of Cellulose and Lignocellulosics Chemistry,Guangzhou Institute of Chemistry,Chinese Academy of Sciences (No.LCLC-2010-08)
文摘The interactions of 4-aminosalicylic acid (4-ASA) and surfactants in aqueous solutions were investigated by using UV-Vis spectra and steady-state fluorescence spectroscopy.The results showed that the strongest peak at UV-vis spectra of 4-ASA aqueous solution in the presence of cationic surfactant and cetyltrimethyl ammonium bromide (CTAB) appeared at 206 nm and took a red shift from 206 nm to 221 nm with the increase of 4-ASA concentrations from 0.8×10-5 to 4.4×10-4 mol/L.Similarly,the strongest peak at UV-vis spectra of 4-ASA aqueous solution in the presence of nonionic surfactant and polyvinylpyrrolidone (PVP) appeared at 206 nm and took a red shift from 206 nm to 219 nm with the increase of 4-ASA concentrations from 0.8×10-5 to 4.4×10-4 mol/L.However,the similar phenomena did not appeared in the presence of anion surfactant,sodium dodecyl sulfate (SDS),the UV-vis spectra of 4-ASA aqueous solution remained the same peak position and the peak value increased with the 4-ASA concentration increase.The results could be attributed to the electrostatic attraction between 4-ASA and CTAB or PVP,as well as the electrostatic repulsion between 4-ASA and SDS.Furthermore,the value of critical micelle concentration (CMC) of surfactants in the presence of 4-ASA was determined with Fluorescence method.The first and second CMC of CTAB was 1.2×10-4 M and 2.4×10-4 M,respectively.The first and second CMC of PVP was 1.2×10-4 M and 2.8×10-4 M.SDS realized the multiple micellizations to form multiple CMC.
文摘This paper is devoted to the study of the potentiality of the Fricke dosimeter for the characterization of the highly energetic (62.1 MeV) α particles beams generated by a new cyclotron facility, namely ARRONAX started in 2009. Such for this high energetic α beam, in situ dosimetry is performed in order to avoid radiation safety inconvenience and to earn run time of irradiation. Therefore, an in situ Fricke dosimetry protocol is developed and its reliability is checked by comparison with other experiments carried out by using the traditional method (ex situ Fricke dosimetry) within another cyclotron facility (CEMHTI) and by comparison with literature data. To author’s knowledge, it is the first time that Fricke dosimetry is performed during the α irradiation experiment. The results of these in situ dosimetry experiments show that the value of ferric ions radiolytic yield (G(Fe3+) = (11.7 ± 1.2) 10–7 mol?J–1) extrapolated from literature data can be used for this higher energy of α particles (Eα = 62.1 MeV).
文摘Chinese liquor Moutai is the “National alcoholic drink” in China and plays a very important role of social activities in Chinese people’s life. In pursuit of high profits, some illegal counterfeit Moutai liquors have begun to appear in the market. Therefore, it is an urgent need for new techniques to discriminate the genuine and counterfeit Moutai liquor. In this work, the conventional Ultraviolet-Visible (UV-Vis) spectroscopy and two-dimensional correlation UV-Vis spectroscopy are applied to obtain the UV-Vis characteristic of Moutai liquor and counterfeit one, respectively. The experimental results reveal that the conventional UV-Vis spectra of the genuine and counterfeit Moutai liquor are similar. However, the two-dimensional correlation UV-Vis spectra of them are different and this method would be applied to differentiate the counterfeit Moutai liquor from the genuine Moutai liquor. Compared with conventional methods, this novel method has the advantages of easy operation, simple instrumentation and direct recognition, which make it a potential tool in the fields of food safety.
文摘Reactive bright blue rare earth dyestuffs were prepared by using reactive bright blue and lanthanum oxide,praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, erbium oxide, lutetium oxide, yttrium oxide respectively for dyeing silk cloth.The degree of dyeing of reactive bright blue praseodymium and the degree of fixation of reactive bright blue gadolinium are the biggest, and 22.9% and 7 %are increased with that of reactive bright blue respectively.The spectra of reactive bright blue rare earth and reactive bright blue were studied by UV-VIS.In 200.00 ~ 800.00 nm, reactive bright blue has four absorption peaks, reactive bright blue rare earth has three absorption peaks; in 420.00 ~ 760.00 nm, reactive bright blue has two absorption peaks at 661.50 nm and 625.50 nm, respectively, and λmax is 661.50 nm; reactive bright blue rare earth has one absorption peak at 620.50, 618.00, 622.00, 623.00, 622.50, 619.50, 619.00, 621.00, 624.00, 620.00 nm adding La3+ ,Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Er3+, Lu3+, Y3+respectively.
文摘The investigation on UV-visible spectra of species formed by extracting some metal picrates with benzo-15-crown-5(B15C5) and dibenzo-18-crown-6(DB18C6) verified that there are some interactions of picrate anion with K+, Na+ and rare earth ions in loaded organic phase. By the study of the charge transfer band and absorption spectra of picrate anion, it can be determined whether an ion pair has been formed and either a 1 : 1 contact ion pair or a 1 : 2 crown-separated ion pair involved in organic phase can be distinguished for an ion-pair extraction.
文摘Being widely used as good ligands,xanthates and related compounds have been extensively investigated.However,reports on Pt(Ⅱ) xanthates have been sparse so far.Watt et al.reported the synthesis and characterization of Pt(S;COR);(R=Me,Et),but did not provide any absorption spectra of these complexes.We prepared twelve platinum (Ⅱ) xanthate complexes and examined their absorption spectra in detail.
基金Project supported by the Shanghai Leading Academic Disciplines,China(Grant No.S30107)
文摘The effect of laser energy density on the crystallization of hydrogenated intrinsic amorphous silicon (a-Si:H) thin films was studied both theoretically and experimentally. The thin films were irritated by a frequency-doubled (λ= 532 nm) Nd:YAG pulsed nanosecond laser. An effective density functional theory model was built to reveal the variation of bandgap energy influenced by thermal stress after laser irradiation. Experimental results establish correlation between the thermal stress and the shift of transverse optical peak in Raman spectroscopy and suggest that the relatively greater shift of the transverse optical (TO) peak can produce higher stress. The highest crystalline fraction (84.5%) is obtained in the optimized laser energy density (1000 mJ/cm2) with a considerable stress release. The absorption edge energy measured by the UV- visible spectra is in fairly good agreement with the bandgap energy in the density functional theory (DFT) simulation.
基金the Shanghai Key Subject (China P1501)Science Technology Foundation of Shanghai (064307054)Science Technology Foundation of Shanghai Universities (167)
文摘Reactive blue rare earth dyestuffs were prepared by using reactive blue and lanthanum oxide, praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, terbium oxide, dysprosium oxide, erbium oxide, lutetium oxide and yttrium oxide respectively for dyeing silk cloth. The degrees of dyeing of reactive blue gadolinium and fixation of reactive blue neodymium were the biggest respectively, were 84.83% and 97.96 respectively, were 24.13% and 8.36% were increased with that of reactive blue respectively. The spectra of reactive blue rare earths and reactive blue were studied by UV-VIS. In 200.00~800.00 nm, the λmax of reactive blue, reactive blue lanthanum, reactive blue praseodymium, reactive blue neodymium, reactive blue samarium, reactive blue europium, reactive blue gadolinium, reactive blue terbium, reactive blue dysprosium, reactive blue erbium, reactive blue lutetium and reactive blue yttrium are 599.00, 600.00, 602.00, 601.00, 600.00, 600.50, 600.50, 601.00, 600.00, 600.50, 599.50 and 600.50 nm respectively. Reactive blue lanthanum, reactive blue praseodymium, reactive blue neodymium, reactive blue samarium, reactive blue europium, reactive blue gadolinium, reactive blue terbium, reactive blue dysprosium, reactive blue erbium, reactive blue lutetium, reactive blue yttrium and reactive blue had almost same color.
基金supported by the National Natural Science Foundation of China(No.21172174)
文摘A bis-2-iminopyrrole compound(1) and its difluoroboron complex(2) were synthesized and characterized. The crystal of 2 is in the monoclinic system, P2_1/n space group with a = 21.5113(15), b = 6.3036(3), c = 21.5064(15) A, V = 2826.3(7) A^3, Z = 4, C_(26.5) H_(25) B_2 ClF_4 N_4 O, M_r = 548.57, D_c = 1.390 g/cm, F(000) = 1132 and μ(MoKα) = 1.787 mm^-1. The final R = 0.0647 and wR = 0.1817 for 10346 observed reflections with I 〉 2σ(I), and R = 0.0889 and wR = 0.1993 for all data. The molecules of complex 2 self-assemble through C–H×××F hydrogen bonds and form tubular structures which are filled by CH_2 Cl_2 molecules stabilized by C–H×××π interaction. The UV-Vis spectra of complex 2 show great bathochromic shift compared to that of compound 1 due to the difluoroboron complexing. Complex 2 shows fluorescence emission both in solid state and in solution, whereas compound 1 only exhibits fluorescence emission in solid state.
文摘The in situ ultraviolet-visible (UV-Vis) spectroelectrochemical study on the copolymerization of diphenylamine (DPA) and o-phenylenediamine (OPD) has been performed at a constant potential of 0.8 V using indium tin oxide (ITO)-coated glass electrodes as working electrode. And also, as a comparison, the electrochemical homopolymerizations of DPA and OPD have been investigated by using the in situ spectroelectrochemical technique. The intermediate species generated during the electrochemical homopoly-merization of DPA and OPD, and the copolymerization of DPA with OPD have been identified by using the in situ spectroelectrochemical procedure. The results reveal the formation of an intermediate in the initial stage of copolymerization through the cross-reaction of the cation radicals of DPA and OPD, and the absorption peak located at 538 nm in the UV–Vis spectra is assigned to this intermediate. To further investigate the copolymerization of DPA with OPD, cyclic voltammetry (CV) has been used to study the electrochemical homopolymerization of DPA and OPD and also the copolymerization of DPA and OPD with different concentration ratios in solution. The different voltammetric characteristics between the homopolymerization and copolymerization processes exhibit the occurrence of the copolymerization, and the difference between the copolymerization of DPA and OPD with different concentration ratios shows the dependence of the copoly-merization on the concentrations of DPA and OPD. The copolymer has also been characterized by Fourier transform infrared spectroscopy (FT-IR).
基金the National Natural Science Foundation of China (92034301,22078063 and 22022804)Major Program of Qingyuan Innovation Laboratory (00121003)the Natural Science Foundation of Fujian Province (2020H6007)。
文摘The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process.
文摘AlPO 4 5 molecular sieve with an orthorhombic phase was studied by in situ variable temperature infrared spectroscopy. The reversible phase transition from the orthorhombic into the hexagonal phase was found at about 120 ℃. [WT5HZ]