The construction of N-fused polycyclic compounds at room temperature via the combination of transition-metal catalyst and photocatalyst has been reported.This novel work has successfully realized LED irradiated C—H a...The construction of N-fused polycyclic compounds at room temperature via the combination of transition-metal catalyst and photocatalyst has been reported.This novel work has successfully realized LED irradiated C—H activation of iodonium ylides.The strategy shows wide substrate scope and ideal functional group tolerance.Our work would be useful for the construction of various heterocyclic compounds.展开更多
Energy efficiency in the petrochemical industry is crucial in reducing energy consumption and environmental impact.An accurate energy efficiency model will provide valuable insight for supporting operational adjustmen...Energy efficiency in the petrochemical industry is crucial in reducing energy consumption and environmental impact.An accurate energy efficiency model will provide valuable insight for supporting operational adjustment decisions.In practice,due to inconsistent sampling intervals in the petrochemical industry,the traditional approach for obtaining energy efficiency may be unreliable and difficult to handle these multirate data char-acteristics.Therefore,in this paper,a multi-channel convolutional neural network model integrating a model parameter-based transfer learning approach is proposed to improve the prediction of energy efficiency under inconsistent sampling intervals.The multi-channel structure aims to recognize a different pattern from the dataset by convolving the information along the time dimension.Concurrently,transfer learning allows the model to learn a new pattern of input after the model is fully trained.Finally,the performance for energy ef-ficiency prediction and saving analysis is validated by applying it to the vinyl chloride monomer production case study.The result shows that the proposed model outperformed traditional models and typical convolutional neural network structures in terms of accuracy and reproducibility,with an r-square of 0.97.The utilization of transfer learning prevents a significant drop in performance and enhances adaptability in model learning on real-time energy tracking.Moreover,the energy gap analysis of the prediction result identified a significant energysaving potential,which would decrease annual energy consumption by 7.25%on average and a 5,709-ton reduction in carbon dioxide emissions.展开更多
Energy efficiency is an important aspect of increasing production capacity, minimizing environmental impact, and reducing energy usage in the petrochemical industries. However, in practice, data quality can be degrade...Energy efficiency is an important aspect of increasing production capacity, minimizing environmental impact, and reducing energy usage in the petrochemical industries. However, in practice, data quality can be degraded by measurement malfunction throughout the operation, leading to unreliable and inaccurate prediction results. Therefore, this paper presents a transfer learning fault detection and identification-energy efficiency predictor (TFDI-EEP) model formulated using long short-term memory. The model aims to predict the energy efficiency of the petrochemical process under uncertainty by using the knowledge gained from the uncertainty detection task to improve prediction performance. The transfer procedure resolves weight initialization by applying partial layer freezing before fine-tuning the additional part of the model. The performance of the proposed model is verified on a wide range of fault variations to thoroughly examine the maximum contribution of faults that the model can tolerate. The results indicate that the TFDI-EEP achieved the highest r-squared and lowest error in the testing step for both the 10% and 20% fault variation datasets compared to other conventional methods. Furthermore, the revelation of interconnection between domains shows that the proposed model can also identify strong fault-correlated features, enhancing monitoring ability and strengthening the robustness and reliability of the model observed by the number of outliers. The transfer parameter improves the prediction performance by 9.86% based on detection accuracy and achieves an r-squared greater than 0.95 on the 40% testing fault variation.展开更多
A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which h...A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which has a unique temperature-dependent backward energy transfer process from selftrapped state to^(4)T_(1)energy level of Mn,is used for triggering the temperature alarm.The LSC with redemitted CsPbI_(3)perovskite-polymer composite films on the glass substrate is used for power supply.The spectrally separated nature between the green-emitted OMHs for temperature alarm and red-emitted CsPbI3in LSC for power supply allows for probing the signal light of temperature-responsive OMHs without the interference of LSCs,making it possible to calibrate the temperature visually just by a self-powered brightness detection circuit with LED indicators.Taking advantage of LSC without hot spot effects plaguing the solar cells,as-prepared temperature alarm system can operate well on both sunny and cloudy day.展开更多
Thermally activated delayed fuorescence(TADF)small molecule bis-[3-(9,9-dimethyl-9,10-dihydroacridine)-phenyl]-sulfone(m-ACSO2)was used as a universal host to sensitize three conventional fuorescent polymers for maxim...Thermally activated delayed fuorescence(TADF)small molecule bis-[3-(9,9-dimethyl-9,10-dihydroacridine)-phenyl]-sulfone(m-ACSO2)was used as a universal host to sensitize three conventional fuorescent polymers for maximizing the electroluminescent performance.The excitons were utilized via inter-molecular energy transfer and the non-radiative decays were successfully refrained in the condensed states.Therefore,the signifcant enhancement of the electroluminescent efciencies was demonstrated.For instance,after doping poly(9,9-dioctylfuorene-co-benzothiadiazole)(F8BT)into m-ACSO2,the external quantum efciency(EQE)was improved by a factor of 17.0 in the solution-processed organic light-emitting device(OLED),as compared with the device with neat F8BT.In terms of the other well-known fuorescent polymers,i.e.,poly(para-phenylene vinylene)copolymer(Super Yellow,SY)and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene](MEH-PPV),their EQEs in the devices were respectively enhanced by 70%and 270%,compared with the reference devices based on the conventional host 1,3-di(9H-carbazol-9-yl)benzene(mCP).Besides the improved charge balance in the bipolar TADF host,these were partially ascribed to reduced fuorescence quenching in the mixed flms.展开更多
Excitation energy transfer in phycoerythrocyanins (PEC) was studied by use of computer simulation. The results observed from the simulation are as follows: (i) The α84 is a more efficient sensitizing chromophore than...Excitation energy transfer in phycoerythrocyanins (PEC) was studied by use of computer simulation. The results observed from the simulation are as follows: (i) The α84 is a more efficient sensitizing chromophore than β155 and donates the excitation energy into β84 and β155 while it scarcely emits fluorescence itself, (ii) Only the 1α84 →2β84 is the sub-picosecond process in a PEC trimer, therefore it is readily to obtain the time constant from fs-level time-resolved spectral measurement. (iii) The β84 and β155 chromophores in PEC behave quite differently from those in C-PC because of the changes in α84. It is observed that 1β156→6β155 is the dominant pathway linking two trimers and both of the chromophores possess much higher fluorescence fractions, and about 80% of the total fluorescence is emitted from the β84 chromophore. (iv) A far less mean number of transfer times is observed through the fast-transfer pairs in PEC compared with that in C-PC because of slow transfer rate for the path from 2β84→1α84. (v) Relatively, PEC could absorb and transfer excitation energy more efficiently than C-PC.展开更多
The spectroscopic properties of a series of Dy^(3+)single-doped and Dy^(3+)/Nd^(3+),Dy^(3+)/Tb^(3+),and Dy^(3+)/Tm^(3+)co-doped YAlO_(3)(yttrium aluminum perovskite,YAP)phosphors were investigated and compared through...The spectroscopic properties of a series of Dy^(3+)single-doped and Dy^(3+)/Nd^(3+),Dy^(3+)/Tb^(3+),and Dy^(3+)/Tm^(3+)co-doped YAlO_(3)(yttrium aluminum perovskite,YAP)phosphors were investigated and compared through the measurements of optical absorption,emission spectra,and fluorescence decay curves.For the Dy^(3+)ion single-doped samples,the intensity of each absorption band increases with an increment in Dy^(3+)ion doping concentration,and the identified strong absorption peak at 447 nm indicates that Dy^(3+):YAP phosphors are suitable to be pumped by a blue laser diode(LD).For all co-doped samples,absorption peaks of Dy^(3+)ion along with some of the absorption bands of Nd^(3+),Tb^(3+),and Tm^(3+)ions are observed.Under 351 and 447 nm excitation,a prominent emission peak at 572 nm was obtained in all the samples,corresponding to Dy^(3+):^(4)F_(9/2)→^(6)H_(13/2)transition.Here,2 at%Dy^(3+):YAP phosphor exhibits the highest yellow emission intensity under 447 nm pumping.Among the three kinds of Dy^(3+)co-doped phosphors,Dy^(3+)/Tb^(3+):YAP phosphor possesses the dominant yellow emission.The fluorescence decay curves show exponential behaviour and are fitted well.The Commission International de L’Eclairage(CIE)chromaticity coordinates were calculated following the respective emission spectra,and it is found that all the coordinates locate in the yellow region.The energy transfer(ET)processes were investigated and the concentration quenching mechanism was discussed.The obtained results suggest that Dy^(3+)-activated YAP phosphors are good candidates for yellow LED applications.展开更多
Based on the crystal structure data of C-phycocyanins from Mastigocladus Laminosus andAgmenellum Quadruplicatum,the energy transfer processes in the βsubunits and the monomers are simulat-ed by the use of computer si...Based on the crystal structure data of C-phycocyanins from Mastigocladus Laminosus andAgmenellum Quadruplicatum,the energy transfer processes in the βsubunits and the monomers are simulat-ed by the use of computer simulation technique.The simulation results show that excitation energy cantransfer in both directions between any pair of chromophores,and furthermore,the transfer can take place intwo opposite directions for many times between a pair of chromophores.There certainly exists energy trans-fer between the two subunits in a monomer.The dynamic nature of the energy transfer processes has beenshown.Besides,it is also indicated that a component obtained from mathematically fitting the experimentaldata cannot be equivalent to a physical process.展开更多
基金the support from Sichuan Science and Technology Program(No.2020YJ0221).
文摘The construction of N-fused polycyclic compounds at room temperature via the combination of transition-metal catalyst and photocatalyst has been reported.This novel work has successfully realized LED irradiated C—H activation of iodonium ylides.The strategy shows wide substrate scope and ideal functional group tolerance.Our work would be useful for the construction of various heterocyclic compounds.
文摘Energy efficiency in the petrochemical industry is crucial in reducing energy consumption and environmental impact.An accurate energy efficiency model will provide valuable insight for supporting operational adjustment decisions.In practice,due to inconsistent sampling intervals in the petrochemical industry,the traditional approach for obtaining energy efficiency may be unreliable and difficult to handle these multirate data char-acteristics.Therefore,in this paper,a multi-channel convolutional neural network model integrating a model parameter-based transfer learning approach is proposed to improve the prediction of energy efficiency under inconsistent sampling intervals.The multi-channel structure aims to recognize a different pattern from the dataset by convolving the information along the time dimension.Concurrently,transfer learning allows the model to learn a new pattern of input after the model is fully trained.Finally,the performance for energy ef-ficiency prediction and saving analysis is validated by applying it to the vinyl chloride monomer production case study.The result shows that the proposed model outperformed traditional models and typical convolutional neural network structures in terms of accuracy and reproducibility,with an r-square of 0.97.The utilization of transfer learning prevents a significant drop in performance and enhances adaptability in model learning on real-time energy tracking.Moreover,the energy gap analysis of the prediction result identified a significant energysaving potential,which would decrease annual energy consumption by 7.25%on average and a 5,709-ton reduction in carbon dioxide emissions.
基金support of the Faculty of Engineering,Kasetsart University(Grant No.65/10/CHEM/M.Eng)the Kasetsart University Research and Development Institute,and Kasetsart University.
文摘Energy efficiency is an important aspect of increasing production capacity, minimizing environmental impact, and reducing energy usage in the petrochemical industries. However, in practice, data quality can be degraded by measurement malfunction throughout the operation, leading to unreliable and inaccurate prediction results. Therefore, this paper presents a transfer learning fault detection and identification-energy efficiency predictor (TFDI-EEP) model formulated using long short-term memory. The model aims to predict the energy efficiency of the petrochemical process under uncertainty by using the knowledge gained from the uncertainty detection task to improve prediction performance. The transfer procedure resolves weight initialization by applying partial layer freezing before fine-tuning the additional part of the model. The performance of the proposed model is verified on a wide range of fault variations to thoroughly examine the maximum contribution of faults that the model can tolerate. The results indicate that the TFDI-EEP achieved the highest r-squared and lowest error in the testing step for both the 10% and 20% fault variation datasets compared to other conventional methods. Furthermore, the revelation of interconnection between domains shows that the proposed model can also identify strong fault-correlated features, enhancing monitoring ability and strengthening the robustness and reliability of the model observed by the number of outliers. The transfer parameter improves the prediction performance by 9.86% based on detection accuracy and achieves an r-squared greater than 0.95 on the 40% testing fault variation.
基金supported by the Natural Science Foundation of China(22075043,21875034,61704093)。
文摘A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which has a unique temperature-dependent backward energy transfer process from selftrapped state to^(4)T_(1)energy level of Mn,is used for triggering the temperature alarm.The LSC with redemitted CsPbI_(3)perovskite-polymer composite films on the glass substrate is used for power supply.The spectrally separated nature between the green-emitted OMHs for temperature alarm and red-emitted CsPbI3in LSC for power supply allows for probing the signal light of temperature-responsive OMHs without the interference of LSCs,making it possible to calibrate the temperature visually just by a self-powered brightness detection circuit with LED indicators.Taking advantage of LSC without hot spot effects plaguing the solar cells,as-prepared temperature alarm system can operate well on both sunny and cloudy day.
基金the fnancial support from the National Natural Science Foundation of China(Grant Nos.51873159 and 62175189)GX acknowledged the funding support from the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2019WNLOKF015).
文摘Thermally activated delayed fuorescence(TADF)small molecule bis-[3-(9,9-dimethyl-9,10-dihydroacridine)-phenyl]-sulfone(m-ACSO2)was used as a universal host to sensitize three conventional fuorescent polymers for maximizing the electroluminescent performance.The excitons were utilized via inter-molecular energy transfer and the non-radiative decays were successfully refrained in the condensed states.Therefore,the signifcant enhancement of the electroluminescent efciencies was demonstrated.For instance,after doping poly(9,9-dioctylfuorene-co-benzothiadiazole)(F8BT)into m-ACSO2,the external quantum efciency(EQE)was improved by a factor of 17.0 in the solution-processed organic light-emitting device(OLED),as compared with the device with neat F8BT.In terms of the other well-known fuorescent polymers,i.e.,poly(para-phenylene vinylene)copolymer(Super Yellow,SY)and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene](MEH-PPV),their EQEs in the devices were respectively enhanced by 70%and 270%,compared with the reference devices based on the conventional host 1,3-di(9H-carbazol-9-yl)benzene(mCP).Besides the improved charge balance in the bipolar TADF host,these were partially ascribed to reduced fuorescence quenching in the mixed flms.
基金Project supported by the National Natural Science Foundation of China
文摘Excitation energy transfer in phycoerythrocyanins (PEC) was studied by use of computer simulation. The results observed from the simulation are as follows: (i) The α84 is a more efficient sensitizing chromophore than β155 and donates the excitation energy into β84 and β155 while it scarcely emits fluorescence itself, (ii) Only the 1α84 →2β84 is the sub-picosecond process in a PEC trimer, therefore it is readily to obtain the time constant from fs-level time-resolved spectral measurement. (iii) The β84 and β155 chromophores in PEC behave quite differently from those in C-PC because of the changes in α84. It is observed that 1β156→6β155 is the dominant pathway linking two trimers and both of the chromophores possess much higher fluorescence fractions, and about 80% of the total fluorescence is emitted from the β84 chromophore. (iv) A far less mean number of transfer times is observed through the fast-transfer pairs in PEC compared with that in C-PC because of slow transfer rate for the path from 2β84→1α84. (v) Relatively, PEC could absorb and transfer excitation energy more efficiently than C-PC.
基金Projects supported by the National Natural Science Foundation of China(51872286,51832007,51472240,61675204)Science and Technology Plan Leading Project of Fujian Province(2018H0046)+3 种基金State Key Laboratory of Rare Earth Resource Utilization(RERU2018004,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences)the National Key Research and Development Program of China(2016YFB0701002)the fund of the State Key Laboratory of Solidification Processing(SKLSP201908,Northwestern Polytechnical University)Natural Science Foundation of Jiangxi Province(20181BAB211009)。
文摘The spectroscopic properties of a series of Dy^(3+)single-doped and Dy^(3+)/Nd^(3+),Dy^(3+)/Tb^(3+),and Dy^(3+)/Tm^(3+)co-doped YAlO_(3)(yttrium aluminum perovskite,YAP)phosphors were investigated and compared through the measurements of optical absorption,emission spectra,and fluorescence decay curves.For the Dy^(3+)ion single-doped samples,the intensity of each absorption band increases with an increment in Dy^(3+)ion doping concentration,and the identified strong absorption peak at 447 nm indicates that Dy^(3+):YAP phosphors are suitable to be pumped by a blue laser diode(LD).For all co-doped samples,absorption peaks of Dy^(3+)ion along with some of the absorption bands of Nd^(3+),Tb^(3+),and Tm^(3+)ions are observed.Under 351 and 447 nm excitation,a prominent emission peak at 572 nm was obtained in all the samples,corresponding to Dy^(3+):^(4)F_(9/2)→^(6)H_(13/2)transition.Here,2 at%Dy^(3+):YAP phosphor exhibits the highest yellow emission intensity under 447 nm pumping.Among the three kinds of Dy^(3+)co-doped phosphors,Dy^(3+)/Tb^(3+):YAP phosphor possesses the dominant yellow emission.The fluorescence decay curves show exponential behaviour and are fitted well.The Commission International de L’Eclairage(CIE)chromaticity coordinates were calculated following the respective emission spectra,and it is found that all the coordinates locate in the yellow region.The energy transfer(ET)processes were investigated and the concentration quenching mechanism was discussed.The obtained results suggest that Dy^(3+)-activated YAP phosphors are good candidates for yellow LED applications.
基金supported by the National Natural Science Foundation of China
文摘Based on the crystal structure data of C-phycocyanins from Mastigocladus Laminosus andAgmenellum Quadruplicatum,the energy transfer processes in the βsubunits and the monomers are simulat-ed by the use of computer simulation technique.The simulation results show that excitation energy cantransfer in both directions between any pair of chromophores,and furthermore,the transfer can take place intwo opposite directions for many times between a pair of chromophores.There certainly exists energy trans-fer between the two subunits in a monomer.The dynamic nature of the energy transfer processes has beenshown.Besides,it is also indicated that a component obtained from mathematically fitting the experimentaldata cannot be equivalent to a physical process.
