By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is de...By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is derived. Based on the derived solutions and using some multi-valued functions, we obtain some novel folded localized excitations of the system.展开更多
Based on the B/icklund method and the multilinear variable separation approach (MLVSA), this paper finds a general solution including two arbitrary functions for the (2+1)-dimensional Burgers equations. Then a cl...Based on the B/icklund method and the multilinear variable separation approach (MLVSA), this paper finds a general solution including two arbitrary functions for the (2+1)-dimensional Burgers equations. Then a class of new doubly periodic wave solutions for (2+l)-dimensional Burgers equations is obtained by introducing appropriate Jacobi elliptic functions, Weierstrass elliptic functions and their combination in the general solutions (which contains two arbitrary functions). Two types of limit cases are considered. Firstly, taking one of the moduli to be unity and the other zero, it obtains particular wave (called semi-localized) patterns, which is periodic in one direction, but localized in the other direction. Secondly, if both moduli are tending to 1 as a limit, it derives some novel localized excitations (two-dromion solution).展开更多
Periodic wave solutions and solitary wave solutions to a generalized (3+1)-dimensional Gross Pitaevskii equation with time-modulated dispersion, nonlinearity, and potential are derived in terms of an improved homog...Periodic wave solutions and solitary wave solutions to a generalized (3+1)-dimensional Gross Pitaevskii equation with time-modulated dispersion, nonlinearity, and potential are derived in terms of an improved homogeneous balance principle and a mapping approach. These exact solutions exist under certain conditions via imposing suitable constraints on the functions describing dispersion, nonlinearity, and potential. The dynamics of the derived solutions can be manipulated by prescribing specific time-modulated dispersions, nonlinearities, and potentials. The results show that the periodic waves and solitary waves with novel behaviors are similar to the similaritons reported in other nonlinear systems.展开更多
By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase...By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase shifts for the interactions of the (2+1)-dimensional novel localized structures, which are discussed in this paper.展开更多
In this work, the excited states of the title compounds are calculated by using time-dependent density functional theory (TDDFT). Firstly, the variation of the sequences of intramolecular charge local excitation (LE) ...In this work, the excited states of the title compounds are calculated by using time-dependent density functional theory (TDDFT). Firstly, the variation of the sequences of intramolecular charge local excitation (LE) and intramolecular charge transfer (CT) in the gas phase is studied by changing electron donors or acceptors. Then, the effects of Polarized Continuum Model (PCM) and Self-consistent Isodensity Polarized Continuum Model (SCI-PCM) in solvents on the calculated results are discussed. It is shown that the calculated results obtained by the PCM are in more agreement with the experimental data. Finally, the excited states of compounds in different solvents were calculated by PCM. Compared with the results obtained in gas phase, the absorption spectra of the CT state in the solvents have a larger red shift; however, the spectra for the LE state are hardly changed.展开更多
We proposc and numerically investigate the optical transmission behaviors of a subwavelength metal film perforated with a two-dimensional square array of compound circular holes.Enhanced optical transmission is obtain...We proposc and numerically investigate the optical transmission behaviors of a subwavelength metal film perforated with a two-dimensional square array of compound circular holes.Enhanced optical transmission is obtained by using the finite-difference time-domain(FDTD)method,which can be mainly attributed to the excitation and coupling of localized surface plasmon resonances(LSPRs) and surface plasmon polaritons(SPPs),and Fano Resonances.The redshift of the transmission peak can be achieved by enlarging the size and number of small holes,the environmental dielectric constant.These indicate that the proposed structure has potential applications in integrated optoelectronic devices such as plasmonic filters and sensors.展开更多
we report a pure rerromagneuc metallic magnetopiasmonic structure consisting or two-dimensional oraerea Ni nanodisks array on Co film.With a sufficient height of the nanodisks,a steep and asymmetric Fano resonance can...we report a pure rerromagneuc metallic magnetopiasmonic structure consisting or two-dimensional oraerea Ni nanodisks array on Co film.With a sufficient height of the nanodisks,a steep and asymmetric Fano resonance can be excited in this structure.We attribute the fascinating spectral lineshape to the strong coupling between the excitation of surface plasmon polaritons at the interface and the localized surface plasmon resonance of nanodisks.The conclusion is fully confirmed by spectrum measurements in nanostructures with different heights.Furthermore,the enhancement and sign of the magneto-optical Kerr rotation in this structure are significantly modified by the Fano resonance.展开更多
Organic scintillators that efficiently generate bright triplet excitons are of critical importance for highperformance X-ray-excited luminescence in radiation detection.However,the nature of triplet-singlet spinforbid...Organic scintillators that efficiently generate bright triplet excitons are of critical importance for highperformance X-ray-excited luminescence in radiation detection.However,the nature of triplet-singlet spinforbidden transitions in these materials often result in long-lived phosphorescence,which is undesirable for ultrafast X-ray detection and imaging.Here we demonstrate that the effect of hybridized local and charge-transfer(HLCT)excited states enables organic scintillators to exhibit highly efficient and fast radioluminescence(RL)in response to X-ray irradiation.Our experimental and theoretical investigation shows that the oxidized 1,8-naphthalimide-phenothiazine dyad(OMNI-PTZ 2)with HLCT-excited states has an enhanced overlap integral of the highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)on MNIπ-orbitals,and moderate donor–acceptor electron interactions.As a result,the RL of these crystals exhibits a 61-fold increase and its monoexponential decay lifetime is three orders of magnitude faster compared to its corresponding thermally activated delayed fluorescence(TADF)molecule MNI-PTZ 1.We further demonstrate the practical utility of the OMNI-PTZ 2(G)in high-performance X-ray detection and imaging,achieving an X-ray dose sensitivity of 97 nGy s−1 and an exceptional spatial resolution of 20 lp/mm.Our study provides a promising molecular design principle for utilizing triplet excitons to develop high-efficiency and fast X-ray scintillators for the development of next-generation flexible and stretchable X-ray imaging detectors.展开更多
The development of fluorescent materials capable of harvesting triplet excitons efficiently is of great importance in achieving high-performance low-cost organic light-emitting diodes(OLEDs).Among the three mechanis...The development of fluorescent materials capable of harvesting triplet excitons efficiently is of great importance in achieving high-performance low-cost organic light-emitting diodes(OLEDs).Among the three mechanisms converting triplet to singlet excitons,triplet fusion delayed fluorescence(TFDF) plays a key role in the demonstration of highly efficient and reliable OLEDs,especially blue devices,for practice applications.This review focuses on the recent development of TFDF materials and their applications in OLEDs.Fundamental TFDF mechanism,molecular design principles,and the structure-property relationship of TFDF materials with a particular emphasis on their different excited state characters,are presented and discussed.Moreover,the future perspectives and ongoing challenges of TFDF materials are also highlighted.展开更多
Improving the utilization of excitons has always been an important topic for the development of electroluminescence devices.In this work,we designed and synthesized three red TADF emitters TPA-DBT12,TPA-DBT3 and DTPA-...Improving the utilization of excitons has always been an important topic for the development of electroluminescence devices.In this work,we designed and synthesized three red TADF emitters TPA-DBT12,TPA-DBT3 and DTPA-DBT by employing dibenzothioxanthone(DBT)acceptor framework to stabilize the locally excited triplet state to participate in the reverse intersystem crossing(RISC)process.The fast RISC process and singlet radiation decay process gave rise to evidently enhanced exciton utilization.All of the red OLEDs based on these materials showed maximum EQE over 11% and high exciton utilization close to 100%.This work not only extend the acceptor framework for red materials but also provide a new perspective for the design of highly efficient red TADF materials with 100% exciton utilization by managing locally excited triplet state.展开更多
Luminogens with aggregation-induced emission(AIE)characteristics(or AIEgens)have been widely used in various applications due to their excellent luminescent properties in molecular aggregates and the solid state.A dee...Luminogens with aggregation-induced emission(AIE)characteristics(or AIEgens)have been widely used in various applications due to their excellent luminescent properties in molecular aggregates and the solid state.A deep understanding of the AIE mechanism is critical for the rational development of AIEgens.In this work,the“state-crossing from a locally excited to an electron transfer state”(SLEET)model is employed to rationalize the AIE phenomenon of two(bi)piperidylanthracenes.According to the SLEET model,an electron transfer(ET)state is formed along with the rotation of the piperidyl group in the excited state of(bi)piperidylan-thracene monomers,leading to fluorescence quenching.In contrast,a bright state exists in the crystal and molecular aggregates of these compounds,as the intermolecular interactions restrict the formation of the dark ET state.This mechanistic understanding could inspire the deployment of the SLEET model in the rational designs of various functional AIEgens.展开更多
基金Project supported by the Natural Science Foundation of Zhejiang Province, China (Grant Nos. Y6100257 and Y6110140)
文摘By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is derived. Based on the derived solutions and using some multi-valued functions, we obtain some novel folded localized excitations of the system.
基金Project supported by the National Natural Science Foundation of China (Grant No 10647112)the Foundation of Donghua University
文摘Based on the B/icklund method and the multilinear variable separation approach (MLVSA), this paper finds a general solution including two arbitrary functions for the (2+1)-dimensional Burgers equations. Then a class of new doubly periodic wave solutions for (2+l)-dimensional Burgers equations is obtained by introducing appropriate Jacobi elliptic functions, Weierstrass elliptic functions and their combination in the general solutions (which contains two arbitrary functions). Two types of limit cases are considered. Firstly, taking one of the moduli to be unity and the other zero, it obtains particular wave (called semi-localized) patterns, which is periodic in one direction, but localized in the other direction. Secondly, if both moduli are tending to 1 as a limit, it derives some novel localized excitations (two-dromion solution).
基金Project supported by the National Natural Science Foundation of China (Grant No. 11172181)the Natural Science Foundation of Guangdong Province, China (Grant No. 10151200501000008)+1 种基金the Special Foundation of Talent Engineering of Guangdong Province, China (Grant No.2009109)the Scientific Research Foundation of Key Discipline of Shaoguan University, China(Grant No. ZD2009001)
文摘Periodic wave solutions and solitary wave solutions to a generalized (3+1)-dimensional Gross Pitaevskii equation with time-modulated dispersion, nonlinearity, and potential are derived in terms of an improved homogeneous balance principle and a mapping approach. These exact solutions exist under certain conditions via imposing suitable constraints on the functions describing dispersion, nonlinearity, and potential. The dynamics of the derived solutions can be manipulated by prescribing specific time-modulated dispersions, nonlinearities, and potentials. The results show that the periodic waves and solitary waves with novel behaviors are similar to the similaritons reported in other nonlinear systems.
基金Project supported by the National Natural Science Foundation of China (Grant No 10272071) and the Key Assisted Academic Discipline of Zhejiang Province (Grant No 200337).
文摘By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase shifts for the interactions of the (2+1)-dimensional novel localized structures, which are discussed in this paper.
基金This work was supported by the Startup Foundation of Scientific Research for the Elitists Introduced into Jinan University
文摘In this work, the excited states of the title compounds are calculated by using time-dependent density functional theory (TDDFT). Firstly, the variation of the sequences of intramolecular charge local excitation (LE) and intramolecular charge transfer (CT) in the gas phase is studied by changing electron donors or acceptors. Then, the effects of Polarized Continuum Model (PCM) and Self-consistent Isodensity Polarized Continuum Model (SCI-PCM) in solvents on the calculated results are discussed. It is shown that the calculated results obtained by the PCM are in more agreement with the experimental data. Finally, the excited states of compounds in different solvents were calculated by PCM. Compared with the results obtained in gas phase, the absorption spectra of the CT state in the solvents have a larger red shift; however, the spectra for the LE state are hardly changed.
基金supported by National Natural Science Foundation of China(Nos.11464019,11264017,11004088)Young Scientist Development Program of China(No.20142BCB23008)the Natural Science Foundation of Jiangxi Province,China(Nos.2014BAB212001,20112BBE5033)
文摘We proposc and numerically investigate the optical transmission behaviors of a subwavelength metal film perforated with a two-dimensional square array of compound circular holes.Enhanced optical transmission is obtained by using the finite-difference time-domain(FDTD)method,which can be mainly attributed to the excitation and coupling of localized surface plasmon resonances(LSPRs) and surface plasmon polaritons(SPPs),and Fano Resonances.The redshift of the transmission peak can be achieved by enlarging the size and number of small holes,the environmental dielectric constant.These indicate that the proposed structure has potential applications in integrated optoelectronic devices such as plasmonic filters and sensors.
基金Project supported by the National Key Project of Fundamental Research of China(Grant No.2012CB932304)the National Natural Science Foundation of China(Grant Nos.11374146 and U1232210)
文摘we report a pure rerromagneuc metallic magnetopiasmonic structure consisting or two-dimensional oraerea Ni nanodisks array on Co film.With a sufficient height of the nanodisks,a steep and asymmetric Fano resonance can be excited in this structure.We attribute the fascinating spectral lineshape to the strong coupling between the excitation of surface plasmon polaritons at the interface and the localized surface plasmon resonance of nanodisks.The conclusion is fully confirmed by spectrum measurements in nanostructures with different heights.Furthermore,the enhancement and sign of the magneto-optical Kerr rotation in this structure are significantly modified by the Fano resonance.
基金supported by the National Key R&D Program of China(grant no.2020YFA0709900)the National Natural Science Foundation of China(grant nos.21971041,22201042,22027805,62134003,and 22104016)+2 种基金the Natural Science Foundation of Fujian Province(grant nos.2020J01447,2022J06008,and 2022J0121)the Research Foundation of Education Bureau of Fujian Province(grant no.JAT210001)the Fuzhou University Testing Fund of Precious Apparatus(grant no.2022T001).
文摘Organic scintillators that efficiently generate bright triplet excitons are of critical importance for highperformance X-ray-excited luminescence in radiation detection.However,the nature of triplet-singlet spinforbidden transitions in these materials often result in long-lived phosphorescence,which is undesirable for ultrafast X-ray detection and imaging.Here we demonstrate that the effect of hybridized local and charge-transfer(HLCT)excited states enables organic scintillators to exhibit highly efficient and fast radioluminescence(RL)in response to X-ray irradiation.Our experimental and theoretical investigation shows that the oxidized 1,8-naphthalimide-phenothiazine dyad(OMNI-PTZ 2)with HLCT-excited states has an enhanced overlap integral of the highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)on MNIπ-orbitals,and moderate donor–acceptor electron interactions.As a result,the RL of these crystals exhibits a 61-fold increase and its monoexponential decay lifetime is three orders of magnitude faster compared to its corresponding thermally activated delayed fluorescence(TADF)molecule MNI-PTZ 1.We further demonstrate the practical utility of the OMNI-PTZ 2(G)in high-performance X-ray detection and imaging,achieving an X-ray dose sensitivity of 97 nGy s−1 and an exceptional spatial resolution of 20 lp/mm.Our study provides a promising molecular design principle for utilizing triplet excitons to develop high-efficiency and fast X-ray scintillators for the development of next-generation flexible and stretchable X-ray imaging detectors.
基金supported by National Natural Science Foundation of China(No.21372168)
文摘The development of fluorescent materials capable of harvesting triplet excitons efficiently is of great importance in achieving high-performance low-cost organic light-emitting diodes(OLEDs).Among the three mechanisms converting triplet to singlet excitons,triplet fusion delayed fluorescence(TFDF) plays a key role in the demonstration of highly efficient and reliable OLEDs,especially blue devices,for practice applications.This review focuses on the recent development of TFDF materials and their applications in OLEDs.Fundamental TFDF mechanism,molecular design principles,and the structure-property relationship of TFDF materials with a particular emphasis on their different excited state characters,are presented and discussed.Moreover,the future perspectives and ongoing challenges of TFDF materials are also highlighted.
基金financially supported by the National Natural Science Foundation of China(No.21772209)the National Program for Support of Top-notch Young Professionals.
文摘Improving the utilization of excitons has always been an important topic for the development of electroluminescence devices.In this work,we designed and synthesized three red TADF emitters TPA-DBT12,TPA-DBT3 and DTPA-DBT by employing dibenzothioxanthone(DBT)acceptor framework to stabilize the locally excited triplet state to participate in the reverse intersystem crossing(RISC)process.The fast RISC process and singlet radiation decay process gave rise to evidently enhanced exciton utilization.All of the red OLEDs based on these materials showed maximum EQE over 11% and high exciton utilization close to 100%.This work not only extend the acceptor framework for red materials but also provide a new perspective for the design of highly efficient red TADF materials with 100% exciton utilization by managing locally excited triplet state.
基金This work was supported by A^(*)STAR under Its Advanced Manufacturing and Engineering Program of Singapore(No.A2083c0051).
文摘Luminogens with aggregation-induced emission(AIE)characteristics(or AIEgens)have been widely used in various applications due to their excellent luminescent properties in molecular aggregates and the solid state.A deep understanding of the AIE mechanism is critical for the rational development of AIEgens.In this work,the“state-crossing from a locally excited to an electron transfer state”(SLEET)model is employed to rationalize the AIE phenomenon of two(bi)piperidylanthracenes.According to the SLEET model,an electron transfer(ET)state is formed along with the rotation of the piperidyl group in the excited state of(bi)piperidylan-thracene monomers,leading to fluorescence quenching.In contrast,a bright state exists in the crystal and molecular aggregates of these compounds,as the intermolecular interactions restrict the formation of the dark ET state.This mechanistic understanding could inspire the deployment of the SLEET model in the rational designs of various functional AIEgens.