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
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
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
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
Two dimethylamino-carbaldehyde derivatives with differentπ-bridge lengths were prepared,and their transient optical properties and photophysical mechanisms were investigated by transient absorption spectroscopy and Z...Two dimethylamino-carbaldehyde derivatives with differentπ-bridge lengths were prepared,and their transient optical properties and photophysical mechanisms were investigated by transient absorption spectroscopy and Z-scan measurements.Owing to the difference in molecular structures,the two compounds exhibit different populations of locally excited states and,therefore,they also produce different transient absorption spectra.After photoexcitation,both molecular materials exhibit a wide excited state absorption band from 450 nm to 1000 nm.Meanwhile,the excited state lifetimes are dramatically different,2 ns and 100 ps,for the two molecules.A figure of merit greater than 2 at the wavelength of1000 nm is obtained.The results show that modulating the population of the locally excited states in this type of molecule can be a promising approach for obtaining optical switching and solar cell materials.展开更多
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.
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%.
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.
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Project supported by the National Natural Science Foundation of China(Grant Nos.U1630103 and 11704273)Natural Science Foundation of Jiangsu Province,China(Grant No.BK20170375)Natural Science Foundation of the Higher Education Institutions of Jiangsu Province,China(Grant No.17KJB140021)
文摘Two dimethylamino-carbaldehyde derivatives with differentπ-bridge lengths were prepared,and their transient optical properties and photophysical mechanisms were investigated by transient absorption spectroscopy and Z-scan measurements.Owing to the difference in molecular structures,the two compounds exhibit different populations of locally excited states and,therefore,they also produce different transient absorption spectra.After photoexcitation,both molecular materials exhibit a wide excited state absorption band from 450 nm to 1000 nm.Meanwhile,the excited state lifetimes are dramatically different,2 ns and 100 ps,for the two molecules.A figure of merit greater than 2 at the wavelength of1000 nm is obtained.The results show that modulating the population of the locally excited states in this type of molecule can be a promising approach for obtaining optical switching and solar cell materials.
