UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing g...UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.展开更多
Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-y...Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-yl) diphenyl ether, bdc2- = 1,3-benzenedicarboxylate), were characterized by single-crystal X-ray diffraction, elemental analysis, PXRD, IR spectroscopy and TGA analysis.Complex 1 crystallizes in monoclinic, space group P21/n, with a = 9.1568(12), b = 16.943(2), c =15.441(2) A, β = 104.049(2)°, V = 2323.9(5) A^3, Dc = 1.420 g/cm^3, Mr = 993.83, F(000) = 1026, μ =0.440 mm-(-1) and Z = 2. Complex 2 crystallizes in monoclinic, space group P21/n, with a =9.1395(17), b = 17.019(3), c = 15.473(3) A, β = 104.651(2)°, V = 2328.5(7) A^3, Dc = 1.414 g/cm^3,Mr = 991.58, F(000) = 1024, μ = 0.487 mm^-1, Z = 2. Complex 3 also belongs to the monoclinic system, space group P21/n, with a = 11.4365(16), b = 18.346(3), c = 11.7068(17) A, β = 91.022(2)°,V = 2455.9(6) A3, Dc = 1.422 g/cm^3, Mr = 1051.66, F(000) = 1092, μ = 0.468 mm^-1, Z = 2. All complexes 1, 2 and 3 are 2D layer structures constructed from intermolecular hydrogen bonds. In addition, the solid UV-vis properties of complexes 1, 2 and 3 were also studied.展开更多
The titled new complex was synthesized and determined by X-ray diffraction. The crystal belongs to monoclinic, P-I group, a=1.8997(4)nm, b-0.581 07(12)nm, c=2.4209(5)nm, β-90.65(3)°, V=2.672 2(9) nm^3,...The titled new complex was synthesized and determined by X-ray diffraction. The crystal belongs to monoclinic, P-I group, a=1.8997(4)nm, b-0.581 07(12)nm, c=2.4209(5)nm, β-90.65(3)°, V=2.672 2(9) nm^3, Z=4, Dc= 1.488 g/cm^3, It has C2 symmetry with the axis through the Zn atom, and the zinc atom is coordinated by two N atoms of the 1-(4-methoxyphenyl) 3-( 1H-1, 2, 4-triazol-1-yl)-1-propanone ligands and two C1^- atoms, forming a slightly distorted tetrahedron. Intermolecular hydrogen bonds make the complex stable. IR and electronic spectra study of the target complex were also carried.展开更多
Two new diarylamine-substituted 1, 8-naphthalimide derivatives are synthesized by Cu I/18-crown-6/K2CO3 catalyst system and characterized by Fourier transform infrared (FT- IR), ^1H-NMR and elemental analyses. The U...Two new diarylamine-substituted 1, 8-naphthalimide derivatives are synthesized by Cu I/18-crown-6/K2CO3 catalyst system and characterized by Fourier transform infrared (FT- IR), ^1H-NMR and elemental analyses. The UV-vis absorption and photoluminescent (PL)spectra of the systems in n-hexane, tetrahydrofuran(THF), and CH2Cl2 are investigated. These naphthalimide molecules have an absorption band centered at about 450 nm, which is assigned to an intramolecular chargetransfer (ICT)transition, and they emit light at 492, 501 nm in a nonpolar solvent such as n-hexane, and at 600, 620 nm in a polar solvent such as CH2Cl2. From the Lippert-Mataga equation, the difference of the dipole moment between the excited state and the ground state is estimated to be 9.2 and 9.8 D for 4- ( diphenylamine )-N-( 2-methoxyphenyl )-1, 8-naphthalimide ( DMN-1 ) and 4-( 2-naphthylphenylamine )-N-( 2- methoxyphenyl)-1, 8-naphthalimide (DMN-2), respectively. This large change in the dipole moment upon excitation is typical for photoinduced ICT processes.展开更多
Optimizing sewage collection is important for water pollution control and wastewater treatment plants quality and efficiency improvement.Currently,the urban drainage pipeline network is upgrading to improve its classi...Optimizing sewage collection is important for water pollution control and wastewater treatment plants quality and efficiency improvement.Currently,the urban drainage pipeline network is upgrading to improve its classification and collection ability.However,there is a lack of efficient online monitoring and identification technology.UV-visible absorption spectrum probe is considered as a potential monitoring method due to its small size,reagent-free and fast detection.Because the performance parameters of probe like optic resolution,dynamic interval and signal-to-noise ratio are weak and high turbidity of sewage raises the noise level,it is necessary to extract shape features from the turbidity disturbed drainage spectrum for classification purposes.In this study,drainage network samples were online collected and tested,and four types were labeled according to sample sites and environment situation.Derivative spectrum were adopted to amplify the shape features,while convolutional neural network algorithm was established to conduct nonlinear spectrum classification.Influence of input and network structure on classification accuracy was compared.Original spectrum,first-order derivative spectrum and a combination of both were set to be three different inputs.Artificial neural network with or without convolutional layer were set be two different network structures.The results revealed a convolutional neural network combined with inputs of first and zero-order derivatives was proposed to have the best classification effect on domestic sewage,mixed rainwater,rainwater and industrial sewage.The recognition rate of industrial wastewater was 100%,and the recognition rate of domestic sewage and rainwater mixing system were over 90%.展开更多
The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effec...The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effects and affect the determination of dissolution rate assaying. In this study, the technique of differential spectra was employed, which made it possible to monitor the dissolution testing in situ. The results showed that the hydrolyzation of aspirin made the percentage of salicylic acid exceed the limit of free salicylic acid (4.0), and the hydrolyzation may affect the quality detection of aspirin delayed-release tablets.展开更多
Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be ...Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be strictly controlled.The bond length,bond angle,energy,dipole moment,orbital energy level distribution of dioxin under the external field are investigated using DFT(density functional theory)on basis set level of B3LYP/6-31G(d,p).The results indicate that with the increase of the electric field,the length of one Carbon-Oxygen bond increases while another Carbon-Oxygen bond decreases.The energy gradually decreases with the electric field,while the change of the dipole moment has an opposite trend.In the infrared spectra,the vibration frequency decreases with the electric field increasing and shows an obvious red shift.Moreover,the ultraviolet-visible absorption spectra under different electric fields are analyzed with TD-DFT(time-dependent density functional theory)method.The wavelength of the strongest absorption peak increases and occurs red shift with the increase of the electric field.All the above results can provide reference for further research on the properties of dioxin under different external electric field.展开更多
UV-Vis spectrum was utilized to study the aggregation behaviors of H4THPP2+ inDMF-chloroform mixture and water. It was found that J-aggregation of H4THPP2+ was formed inDMF-chloroform mixture and H-aggregate was forme...UV-Vis spectrum was utilized to study the aggregation behaviors of H4THPP2+ inDMF-chloroform mixture and water. It was found that J-aggregation of H4THPP2+ was formed inDMF-chloroform mixture and H-aggregate was formed in aqueous solution with highionic-strength, as indicated by different spectral characteristics of different H4THPP2+ aggregates.展开更多
A nest-like architectures(ZnO NAs)were prepared onto the conductive glass(ITO)by hydrothermal method.A metal-free porphyrin,tetraphenylporphyrin(H2TPP),was synthesized via Adler method.Zn ions with Zn-unsaturated coor...A nest-like architectures(ZnO NAs)were prepared onto the conductive glass(ITO)by hydrothermal method.A metal-free porphyrin,tetraphenylporphyrin(H2TPP),was synthesized via Adler method.Zn ions with Zn-unsaturated coordination bonds on the surface of ZnO NAs were used as a template,and also H2TPP was used as"molecular fragments".Zinc tetraphenylporphyrin(ZnTPP)molecules were obtained on the surface of ZnO NAs by in-situ method.ZnO NAs direct provides of zinc source makes ZnTPP stably coated on the surface of ZnO NAs nanosheet,formed a tight composite materials(ZnTPP/ZnO NAs).Due toZnTPP with four phenyls in meso position,the surface of ZnTPP/ZnO NAs was with hydrophobic property.In the photocatalytic experiment,the degradation selectivity for phenol(hydrophobicity)in the mixture of phenol and rhodamine B(hydrophily)was increased under visible irradiation.展开更多
A new class of metal phthalocyanines(MPcs) containing four 8-quinolinol(8-QH) derivative moieties were successfully synthesized and characterized by mass spectroscopy, IR, UV-Vis and element analysis, the results ...A new class of metal phthalocyanines(MPcs) containing four 8-quinolinol(8-QH) derivative moieties were successfully synthesized and characterized by mass spectroscopy, IR, UV-Vis and element analysis, the results of which were consistent with the proposed structures. All of them can dissolve in common organic solvents, such as dichloromethane, chloroform, and acetone. The effect of metal ion on the absorption of Q band was studied with UV-Vis spectra. The fluorescent properties for those complexes were also investigated.展开更多
The ethyl coumarin-3-carboxylate (1) and its two derivatives, ethyl 7-methoxy-2- oxo-2H-chromene-3-carboxylate (2) and ethyl 7-(3-methylbut-2-enyloxy)-2-oxo-2H-chromene-3- carboxylate(3), were synthesized, cha...The ethyl coumarin-3-carboxylate (1) and its two derivatives, ethyl 7-methoxy-2- oxo-2H-chromene-3-carboxylate (2) and ethyl 7-(3-methylbut-2-enyloxy)-2-oxo-2H-chromene-3- carboxylate(3), were synthesized, characterized and their UV-vis spectra and photoluminescence were investigated. Compound 2 crystallizes in the monoclinic system with space group C2/c, a = 25.884(4), b = 6.8365(11), c = 13.816(2) A, β = 104.876(2)°, V= 2362.9(7) A3, Z = 8, Dc= 1.396 g/cm3, Mr. = 248.23, F(000) = 1040 and g = 0.108 mm-1. Compound 3 crystallizes in the monoclinic system with space group P21/c, a = 15.685(6), b = 8.373(3), c = i3.063(5) A, β = 111.862(6)°, V= 1592.2(10) A3, Z = 4, Dc = 1.261 g/cm3, M,.= 302.31, F(000) = 640 and p = 0.093 mm^-1. Both the absorption and emission of the two derivatives were stronger than that of ethyl coumarin-3-carboxylate due to the larger conjugation of their electron donor group moiety at the 7-position. Under ultraviolet light excitation, the two derivatives exhibit strong blue-violet emission.展开更多
The aggregation of meso-tetrakis(4-hydroxyphenyl)porphyrin (H2THPP) in dimethyl- formamide (DMF)-water solution and in DMF-chloroform solution was studied by UV-vis absorption spectroscopy. The red shift of Soret ba...The aggregation of meso-tetrakis(4-hydroxyphenyl)porphyrin (H2THPP) in dimethyl- formamide (DMF)-water solution and in DMF-chloroform solution was studied by UV-vis absorption spectroscopy. The red shift of Soret band indicates the formation of J-type aggregates of H2THPP in these two solutions. However, different shift extent of Soret band, 12 nm in DMF-water solution and 32 nm in DMF-chloroform solution, implies structural difference between these two J-type aggregates. The hydrogen bond between hydroxyl group and N-H bonds in porphyrin ring is thought as the main cause to the formation of J-type aggregate in DMF- chloroform solution, whereas the π?σ interaction between two adjacent porphyrin cores is thought as the main cause of the formation of J-type aggregate in DMF-water solution展开更多
A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and w...A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with α = 15.478(6), b = 12.865(5), c = 24.091(10) ?, β = 95.599(5)°, V = 4774(3) ?3, C24H18CoN2O5, Mr = 473.34, Dc = 1.267 g/cm3, F(000) = 1864.0, μ = 0.748 mm-1 and Z = 8. Each Co(II) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied.展开更多
A series of tetrahedral iridium carbonyl clusters coordinated by systematically varied series of ligands have been studied by TDDFT method focusing on their electronic and non- linear optical properties. The clusters ...A series of tetrahedral iridium carbonyl clusters coordinated by systematically varied series of ligands have been studied by TDDFT method focusing on their electronic and non- linear optical properties. The clusters of Ir4(CO)12 (1), Ir4(μ-CO)3(CO)9 (2), Ir4(μ-L)(CO)10 (L = dppm 3, dppe 4, (Ph2P)2CHMe 5, Ph2P(CH2)3PPh2 6) and Ir4(CO)10(phen) (phen = 1,10-phen- anthroline) (7) exhibit the first static hyperpolarizabilities of medium magnitude (βtot-10×10^-30 esu). The second order nonlinear optical response of the seven clusters increase from 0 to 23 ×10^-30 esu; the high symmetric cluster Ir4(CO)12 debases its symmetry and presents the second order nonlinear optical behavior as the coordination style of some carbonyls changes to bridge style, and then the response increases regularly with the systematical variation of the ligands. The origination of the first hyperpolarizability is discussed by the expanded orbital decomposition scheme. The results suggest the d-d electron transition from the apical iridium atom to the other three Ir atoms inside the metal skeleton, and d-πelectron transitions from metals to carbonyls are responsible for the first hyperpolarizabilities. Particularly, for cluster 7, the charge transfer from d orbitals of iridium to π* orbirals of phenanthroline originates the first hyperpolarizabilities.展开更多
Mixed-metal carbonyl clusters of W2Ir2(CO)10(η^5-C5H4Me)2 1 and W2Ir2(μ-L)(CO)8(η^5-C5H4Me)2 (L = dppe 2, dppf 3) have been studied by TDDFT method focusing on their electronic and nonlinear optical pro...Mixed-metal carbonyl clusters of W2Ir2(CO)10(η^5-C5H4Me)2 1 and W2Ir2(μ-L)(CO)8(η^5-C5H4Me)2 (L = dppe 2, dppf 3) have been studied by TDDFT method focusing on their electronic and nonlinear optical properties. These three clusters exhibit the first static hyperpolarizabilities of medium magnitude (βtot-10×10^-30 esu). The origin of β is discussed by the new proposed orbital-pair decomposition scheme by Barandes et al. The result suggests that the β values of the two clusters are mainly originated from d-d electron transition within the metal skeleton, and d-p (π*) electron transition from metals to carbonyls and phenyl. The additional coordination by the electron donor group, ferrocene, makes cluster 3 own much larger β values, and the relatively longer range charge transfer from d orbitals of ferrocene to d orbirals of Ir and W is responsible for the enhanced β values.展开更多
A simple, quick, sensitive, accurate and precise method has been developed for evaluating the catalytic active sites of titanium silicalite-1 (TS-1). The catalytic active sites of titanium silicalite zeolite depend on...A simple, quick, sensitive, accurate and precise method has been developed for evaluating the catalytic active sites of titanium silicalite-1 (TS-1). The catalytic active sites of titanium silicalite zeolite depend on the effectively active species (EAS) in TS-1 which react with specific substrates quickly. However, the EAS was hard to be evaluated with conventional instruments and techniques in the past. In this paper, the EAS was formed in TS-1 upon interaction with H2O2, and its presence could be confirmed by UV-vis spectroscopy which has an absorption peak at 385 nm. The absorbance at 385 nm was found to be linearly related to time, and when the absorbance and the increasing rate of absorbance (k) increased, the catalytic performance of TS-1 enhanced.展开更多
In this study,twenty disazo reactive red dyes with J acid as coupling components were selected,and their ground state geometry were studied with BLYP functional and TZVP basis set. The UV-vis absorption spectra were c...In this study,twenty disazo reactive red dyes with J acid as coupling components were selected,and their ground state geometry were studied with BLYP functional and TZVP basis set. The UV-vis absorption spectra were calculated by time-dependent density functional theory(TDDFT) employing B3 LYP and PBE0 hybrid functionals and TZVP basis set,and the absolute mean errors are 0.094 e V and 0.133 e V for B3 LYP and PBE0,respectively. From the comparison of the calculated λ_(max) of the three conformations of disazo reactive red dye,cis-,trans-,and azo,with that of experimental one,we find out that conformation plays an important role on UV-Vis absorption. Dyes 6 and 8 exist in azo conformation rather than in cis-conformation. "Hole-electron" distribution analysis reveals that although these λ_(max) arises from different electron transitions,these electron excitations have the same character of local excitation(LE).展开更多
Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties of receptors with some anions (π-O2NPhOPO 3 2? , π-O2NPhO?, H2PO 4 ? , Ac?, Cl?, Br? ...Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties of receptors with some anions (π-O2NPhOPO 3 2? , π-O2NPhO?, H2PO 4 ? , Ac?, Cl?, Br? and I?) were studied by UV-Vis spectra. The results indicate that the tetraamide calix[4]arenes (5, 6) have a good selectivity to the anions containing aromatic ring (π-O2NPhOPO3 2?, π-O2NPhO?). The 1 : 1 complexes between host and guest were formed through multiple hydrogen bonding and π-π interactions. The hosts 5 and 6 also show a definite binding ability for the anions (H2PO 4 ? , Ac?, Cl?) that have no ultraviolet absorption, which provides a simple method of spectrum detection for these anions.展开更多
基金supported by the National Natural Science Foundation of China(21172161)
文摘UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.
基金supported by the Natural Science Foundation of China(21301005)Natural Science Foundation of Anhui Province(1408085QB31)
文摘Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-yl) diphenyl ether, bdc2- = 1,3-benzenedicarboxylate), were characterized by single-crystal X-ray diffraction, elemental analysis, PXRD, IR spectroscopy and TGA analysis.Complex 1 crystallizes in monoclinic, space group P21/n, with a = 9.1568(12), b = 16.943(2), c =15.441(2) A, β = 104.049(2)°, V = 2323.9(5) A^3, Dc = 1.420 g/cm^3, Mr = 993.83, F(000) = 1026, μ =0.440 mm-(-1) and Z = 2. Complex 2 crystallizes in monoclinic, space group P21/n, with a =9.1395(17), b = 17.019(3), c = 15.473(3) A, β = 104.651(2)°, V = 2328.5(7) A^3, Dc = 1.414 g/cm^3,Mr = 991.58, F(000) = 1024, μ = 0.487 mm^-1, Z = 2. Complex 3 also belongs to the monoclinic system, space group P21/n, with a = 11.4365(16), b = 18.346(3), c = 11.7068(17) A, β = 91.022(2)°,V = 2455.9(6) A3, Dc = 1.422 g/cm^3, Mr = 1051.66, F(000) = 1092, μ = 0.468 mm^-1, Z = 2. All complexes 1, 2 and 3 are 2D layer structures constructed from intermolecular hydrogen bonds. In addition, the solid UV-vis properties of complexes 1, 2 and 3 were also studied.
文摘The titled new complex was synthesized and determined by X-ray diffraction. The crystal belongs to monoclinic, P-I group, a=1.8997(4)nm, b-0.581 07(12)nm, c=2.4209(5)nm, β-90.65(3)°, V=2.672 2(9) nm^3, Z=4, Dc= 1.488 g/cm^3, It has C2 symmetry with the axis through the Zn atom, and the zinc atom is coordinated by two N atoms of the 1-(4-methoxyphenyl) 3-( 1H-1, 2, 4-triazol-1-yl)-1-propanone ligands and two C1^- atoms, forming a slightly distorted tetrahedron. Intermolecular hydrogen bonds make the complex stable. IR and electronic spectra study of the target complex were also carried.
基金The Ph.D.Programs Foundation of Ministry of Educa-tion of China(No.20030286012)the High Technology Research and De-velopment Program of Jiangsu Province(No.BG2005034)
文摘Two new diarylamine-substituted 1, 8-naphthalimide derivatives are synthesized by Cu I/18-crown-6/K2CO3 catalyst system and characterized by Fourier transform infrared (FT- IR), ^1H-NMR and elemental analyses. The UV-vis absorption and photoluminescent (PL)spectra of the systems in n-hexane, tetrahydrofuran(THF), and CH2Cl2 are investigated. These naphthalimide molecules have an absorption band centered at about 450 nm, which is assigned to an intramolecular chargetransfer (ICT)transition, and they emit light at 492, 501 nm in a nonpolar solvent such as n-hexane, and at 600, 620 nm in a polar solvent such as CH2Cl2. From the Lippert-Mataga equation, the difference of the dipole moment between the excited state and the ground state is estimated to be 9.2 and 9.8 D for 4- ( diphenylamine )-N-( 2-methoxyphenyl )-1, 8-naphthalimide ( DMN-1 ) and 4-( 2-naphthylphenylamine )-N-( 2- methoxyphenyl)-1, 8-naphthalimide (DMN-2), respectively. This large change in the dipole moment upon excitation is typical for photoinduced ICT processes.
基金supported by the National Key R&D Program of China(No.2019YFD1100505)the program of China Scholarship Council(No.201806210101).
文摘Optimizing sewage collection is important for water pollution control and wastewater treatment plants quality and efficiency improvement.Currently,the urban drainage pipeline network is upgrading to improve its classification and collection ability.However,there is a lack of efficient online monitoring and identification technology.UV-visible absorption spectrum probe is considered as a potential monitoring method due to its small size,reagent-free and fast detection.Because the performance parameters of probe like optic resolution,dynamic interval and signal-to-noise ratio are weak and high turbidity of sewage raises the noise level,it is necessary to extract shape features from the turbidity disturbed drainage spectrum for classification purposes.In this study,drainage network samples were online collected and tested,and four types were labeled according to sample sites and environment situation.Derivative spectrum were adopted to amplify the shape features,while convolutional neural network algorithm was established to conduct nonlinear spectrum classification.Influence of input and network structure on classification accuracy was compared.Original spectrum,first-order derivative spectrum and a combination of both were set to be three different inputs.Artificial neural network with or without convolutional layer were set be two different network structures.The results revealed a convolutional neural network combined with inputs of first and zero-order derivatives was proposed to have the best classification effect on domestic sewage,mixed rainwater,rainwater and industrial sewage.The recognition rate of industrial wastewater was 100%,and the recognition rate of domestic sewage and rainwater mixing system were over 90%.
基金supported by the Xinjiang Medical University Scientific Innovation Fund (No. XJC201129)Xinjiang Uygur Autonomous Region Natural Science Fund (No. 2011211A041)
文摘The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effects and affect the determination of dissolution rate assaying. In this study, the technique of differential spectra was employed, which made it possible to monitor the dissolution testing in situ. The results showed that the hydrolyzation of aspirin made the percentage of salicylic acid exceed the limit of free salicylic acid (4.0), and the hydrolyzation may affect the quality detection of aspirin delayed-release tablets.
基金The project is supported by Natural Science Foundation of Xinjiang(No.2017D01B36).
文摘Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be strictly controlled.The bond length,bond angle,energy,dipole moment,orbital energy level distribution of dioxin under the external field are investigated using DFT(density functional theory)on basis set level of B3LYP/6-31G(d,p).The results indicate that with the increase of the electric field,the length of one Carbon-Oxygen bond increases while another Carbon-Oxygen bond decreases.The energy gradually decreases with the electric field,while the change of the dipole moment has an opposite trend.In the infrared spectra,the vibration frequency decreases with the electric field increasing and shows an obvious red shift.Moreover,the ultraviolet-visible absorption spectra under different electric fields are analyzed with TD-DFT(time-dependent density functional theory)method.The wavelength of the strongest absorption peak increases and occurs red shift with the increase of the electric field.All the above results can provide reference for further research on the properties of dioxin under different external electric field.
基金This work is supported by the National Natural Science Foundation of China(Grant No.20303009).
文摘UV-Vis spectrum was utilized to study the aggregation behaviors of H4THPP2+ inDMF-chloroform mixture and water. It was found that J-aggregation of H4THPP2+ was formed inDMF-chloroform mixture and H-aggregate was formed in aqueous solution with highionic-strength, as indicated by different spectral characteristics of different H4THPP2+ aggregates.
文摘A nest-like architectures(ZnO NAs)were prepared onto the conductive glass(ITO)by hydrothermal method.A metal-free porphyrin,tetraphenylporphyrin(H2TPP),was synthesized via Adler method.Zn ions with Zn-unsaturated coordination bonds on the surface of ZnO NAs were used as a template,and also H2TPP was used as"molecular fragments".Zinc tetraphenylporphyrin(ZnTPP)molecules were obtained on the surface of ZnO NAs by in-situ method.ZnO NAs direct provides of zinc source makes ZnTPP stably coated on the surface of ZnO NAs nanosheet,formed a tight composite materials(ZnTPP/ZnO NAs).Due toZnTPP with four phenyls in meso position,the surface of ZnTPP/ZnO NAs was with hydrophobic property.In the photocatalytic experiment,the degradation selectivity for phenol(hydrophobicity)in the mixture of phenol and rhodamine B(hydrophily)was increased under visible irradiation.
基金Supported by the Application Foundation of Science and Technology Office of Jilin Province, China(No20010512)the Ministry of Education of China(No990254)
文摘A new class of metal phthalocyanines(MPcs) containing four 8-quinolinol(8-QH) derivative moieties were successfully synthesized and characterized by mass spectroscopy, IR, UV-Vis and element analysis, the results of which were consistent with the proposed structures. All of them can dissolve in common organic solvents, such as dichloromethane, chloroform, and acetone. The effect of metal ion on the absorption of Q band was studied with UV-Vis spectra. The fluorescent properties for those complexes were also investigated.
基金supported by Xi'an science and technology plan project(No.CX12189WL16)the National Natural Science Foundation of China(No.51002119)
文摘The ethyl coumarin-3-carboxylate (1) and its two derivatives, ethyl 7-methoxy-2- oxo-2H-chromene-3-carboxylate (2) and ethyl 7-(3-methylbut-2-enyloxy)-2-oxo-2H-chromene-3- carboxylate(3), were synthesized, characterized and their UV-vis spectra and photoluminescence were investigated. Compound 2 crystallizes in the monoclinic system with space group C2/c, a = 25.884(4), b = 6.8365(11), c = 13.816(2) A, β = 104.876(2)°, V= 2362.9(7) A3, Z = 8, Dc= 1.396 g/cm3, Mr. = 248.23, F(000) = 1040 and g = 0.108 mm-1. Compound 3 crystallizes in the monoclinic system with space group P21/c, a = 15.685(6), b = 8.373(3), c = i3.063(5) A, β = 111.862(6)°, V= 1592.2(10) A3, Z = 4, Dc = 1.261 g/cm3, M,.= 302.31, F(000) = 640 and p = 0.093 mm^-1. Both the absorption and emission of the two derivatives were stronger than that of ethyl coumarin-3-carboxylate due to the larger conjugation of their electron donor group moiety at the 7-position. Under ultraviolet light excitation, the two derivatives exhibit strong blue-violet emission.
基金supported by the National Natural Science Foundation of China(Grant No.20303009)
文摘The aggregation of meso-tetrakis(4-hydroxyphenyl)porphyrin (H2THPP) in dimethyl- formamide (DMF)-water solution and in DMF-chloroform solution was studied by UV-vis absorption spectroscopy. The red shift of Soret band indicates the formation of J-type aggregates of H2THPP in these two solutions. However, different shift extent of Soret band, 12 nm in DMF-water solution and 32 nm in DMF-chloroform solution, implies structural difference between these two J-type aggregates. The hydrogen bond between hydroxyl group and N-H bonds in porphyrin ring is thought as the main cause to the formation of J-type aggregate in DMF- chloroform solution, whereas the π?σ interaction between two adjacent porphyrin cores is thought as the main cause of the formation of J-type aggregate in DMF-water solution
基金supported by the National Natural Science Foundation of China(21301005,21271008,51173002)Natural Science Foundation of Anhui Province(1308085QB34)the young teacher’s research foundation of Anhui University of Science and Technology(11227,2012QNZ08)
文摘A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with α = 15.478(6), b = 12.865(5), c = 24.091(10) ?, β = 95.599(5)°, V = 4774(3) ?3, C24H18CoN2O5, Mr = 473.34, Dc = 1.267 g/cm3, F(000) = 1864.0, μ = 0.748 mm-1 and Z = 8. Each Co(II) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied.
基金Supported by the National Natural Science Foundation of China (20573114)the MOST (2006DFA43020)Natural Science Foundation of Fujian Province (2006F3133 and 13071062)
文摘A series of tetrahedral iridium carbonyl clusters coordinated by systematically varied series of ligands have been studied by TDDFT method focusing on their electronic and non- linear optical properties. The clusters of Ir4(CO)12 (1), Ir4(μ-CO)3(CO)9 (2), Ir4(μ-L)(CO)10 (L = dppm 3, dppe 4, (Ph2P)2CHMe 5, Ph2P(CH2)3PPh2 6) and Ir4(CO)10(phen) (phen = 1,10-phen- anthroline) (7) exhibit the first static hyperpolarizabilities of medium magnitude (βtot-10×10^-30 esu). The second order nonlinear optical response of the seven clusters increase from 0 to 23 ×10^-30 esu; the high symmetric cluster Ir4(CO)12 debases its symmetry and presents the second order nonlinear optical behavior as the coordination style of some carbonyls changes to bridge style, and then the response increases regularly with the systematical variation of the ligands. The origination of the first hyperpolarizability is discussed by the expanded orbital decomposition scheme. The results suggest the d-d electron transition from the apical iridium atom to the other three Ir atoms inside the metal skeleton, and d-πelectron transitions from metals to carbonyls are responsible for the first hyperpolarizabilities. Particularly, for cluster 7, the charge transfer from d orbitals of iridium to π* orbirals of phenanthroline originates the first hyperpolarizabilities.
基金Supported by the National Natural Science Foundation of China (20573114)the MOST (2006DFA43020)Natural Science Foundation of Fujian Province (2006F3133)
文摘Mixed-metal carbonyl clusters of W2Ir2(CO)10(η^5-C5H4Me)2 1 and W2Ir2(μ-L)(CO)8(η^5-C5H4Me)2 (L = dppe 2, dppf 3) have been studied by TDDFT method focusing on their electronic and nonlinear optical properties. These three clusters exhibit the first static hyperpolarizabilities of medium magnitude (βtot-10×10^-30 esu). The origin of β is discussed by the new proposed orbital-pair decomposition scheme by Barandes et al. The result suggests that the β values of the two clusters are mainly originated from d-d electron transition within the metal skeleton, and d-p (π*) electron transition from metals to carbonyls and phenyl. The additional coordination by the electron donor group, ferrocene, makes cluster 3 own much larger β values, and the relatively longer range charge transfer from d orbitals of ferrocene to d orbirals of Ir and W is responsible for the enhanced β values.
文摘A simple, quick, sensitive, accurate and precise method has been developed for evaluating the catalytic active sites of titanium silicalite-1 (TS-1). The catalytic active sites of titanium silicalite zeolite depend on the effectively active species (EAS) in TS-1 which react with specific substrates quickly. However, the EAS was hard to be evaluated with conventional instruments and techniques in the past. In this paper, the EAS was formed in TS-1 upon interaction with H2O2, and its presence could be confirmed by UV-vis spectroscopy which has an absorption peak at 385 nm. The absorbance at 385 nm was found to be linearly related to time, and when the absorbance and the increasing rate of absorbance (k) increased, the catalytic performance of TS-1 enhanced.
基金Supported by the Natural Science Foundation of Hubei Province(2010CDA089)the Foundation of Hubei Provincial Education Department(D20131605)the Discipline Innovation Team Project of Wuhan Textile University(201401020)
文摘In this study,twenty disazo reactive red dyes with J acid as coupling components were selected,and their ground state geometry were studied with BLYP functional and TZVP basis set. The UV-vis absorption spectra were calculated by time-dependent density functional theory(TDDFT) employing B3 LYP and PBE0 hybrid functionals and TZVP basis set,and the absolute mean errors are 0.094 e V and 0.133 e V for B3 LYP and PBE0,respectively. From the comparison of the calculated λ_(max) of the three conformations of disazo reactive red dye,cis-,trans-,and azo,with that of experimental one,we find out that conformation plays an important role on UV-Vis absorption. Dyes 6 and 8 exist in azo conformation rather than in cis-conformation. "Hole-electron" distribution analysis reveals that although these λ_(max) arises from different electron transitions,these electron excitations have the same character of local excitation(LE).
基金This work was supported by the National Natural Science Foundation of China(Grant No.20072029).
文摘Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties of receptors with some anions (π-O2NPhOPO 3 2? , π-O2NPhO?, H2PO 4 ? , Ac?, Cl?, Br? and I?) were studied by UV-Vis spectra. The results indicate that the tetraamide calix[4]arenes (5, 6) have a good selectivity to the anions containing aromatic ring (π-O2NPhOPO3 2?, π-O2NPhO?). The 1 : 1 complexes between host and guest were formed through multiple hydrogen bonding and π-π interactions. The hosts 5 and 6 also show a definite binding ability for the anions (H2PO 4 ? , Ac?, Cl?) that have no ultraviolet absorption, which provides a simple method of spectrum detection for these anions.