This work aimed at investigating the crucial factor in building and maintaining the combustion front during in-situ combustion(ISC),oxidized coke and pyrolyzed coke.The surface morphologies,elemental contents,and non-...This work aimed at investigating the crucial factor in building and maintaining the combustion front during in-situ combustion(ISC),oxidized coke and pyrolyzed coke.The surface morphologies,elemental contents,and non-isothermal mass losses of the oxidized and pyrolyzed cokes were thoroughly examined.The results indicated that the oxidized coke could be combusted at a lower temperature compared to the pyrolyzed coke due primarily to their differences in the molecular polarity and microstructure.Kinetic triplets of coke combustion were determined using iso-conversional models and one advanced integral master plots method.The activation energy values of the oxidized and pyrolyzed cokes varied in the range of 130-153 k J/mol and 95-120 kJ/mol,respectively.The most appropriate reaction model of combustion of the oxidized and pyrolyzed cokes followed three-dimensional diffusion model(D_(3)) and random nucleation and subsequent growth model(F_(1)),respectively.These observations assisted in building the numerical model of these two types of cokes to simulate the ISC process.展开更多
We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL)theory.Compared with the regular square ...We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL)theory.Compared with the regular square array of circular holes,the vortices are no longer pinned inside the circular holes,but instead stabilized at the center of the antidot triplets depending on the geometry parameters.Moreover,the influences of the geometry parameters and the polarity of the applied current on the current–voltage(I–V)characteristics are also studied.The critical current for the sample turning into a normal state becomes smaller when the hole diameter D is smaller and the spacing B between the holes is larger.Due to the asymmetric pinning sites,our numerical simulations demonstrate that the positive and negative rectified voltages appear alternately in the resistive state of the sample under an ac current of square pulses.展开更多
Quantum light sources are the core resources for photonics-based quantum information processing.We investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversio...Quantum light sources are the core resources for photonics-based quantum information processing.We investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversion in micro/nanofiber.The phase mismatching at one-third pump frequency gives rise to non-degenerate photon triplets,the joint spectral intensity of which has an elliptical locus with a fixed eccentricity of√6/3.Therefore,we propose a frequency-division scheme to separate non-degenerate photon triplets into three channels with high heralding efficiency for the first time.Choosing an appropriate pump wavelength can compensate for the fabrication errors of micro/nanofiber and also generate narrowband,non-degenerate photon triplet sources with a high signal-to-noise ratio.Furthermore,the long-period micro/nanofiber grating introduces a new controllable degree of freedom to tailor phase matching,resulting from the periodic oscillation of dispersion.In this scheme,the wavelength of photon triplets can be flexibly tuned using quasi-phase matching.We study the generation of photon triplets from this novel perspective of spectrum engineering,and we believe that this work will accelerate the practical implementation of photon triplets in quantum information processing.展开更多
The electroluminescence (EL) produced by a highly luminescent phosphorescent dye Cu-4(CdropCPh)(4)L-2 (L = 1.8-bis(di-phenylphosphino)-3,6-dioxaoctane, Cu-4) doped polymer as emitting layer is reported. The effects of...The electroluminescence (EL) produced by a highly luminescent phosphorescent dye Cu-4(CdropCPh)(4)L-2 (L = 1.8-bis(di-phenylphosphino)-3,6-dioxaoctane, Cu-4) doped polymer as emitting layer is reported. The effects of the charge injection balance on the polymers, in particular, poly(N-vinylcarbazole) (PVK) have been studied by using photoluminescence and electroluminescence spectroscopy. Changes in the emission spectra demonstrate the influence of the charge injection balance on the formation ratio of triplet and singlet excitons. This provides a new technical approach to realize the color patterning in polymer LEDs.展开更多
Sensitizing molecular triplets by colloidal nanocrystals via triplet energy transfer is important for applications such as upconversion or organic synthesis.Typically two step triplet energy transfer(TET)are included ...Sensitizing molecular triplets by colloidal nanocrystals via triplet energy transfer is important for applications such as upconversion or organic synthesis.Typically two step triplet energy transfer(TET)are included in these applications:firstly the triplet energy stored in nanocrystals are extracted into surface ligands,and then the ligands further transfer triplet energy into molecules in bulk solution.Here we report one-step TET application from CsPbBr_(3) perovskite nanocrystals(NCs)to surface-anchored metalloporphyrin derivative molecules(MP).Compared to conventional two-step TET,the one-step TET mechanism possess lower energy loss and higher TET efficiency which is more generally implementable.In this scheme,photoexcitation of CsPbBr_(3)NCs leads to the sensitization of MP ligands triplets which efficiently emit phosphorescence.The enhanced light absorption of MP ligands and down-shifted photon emission can be useful in devices such as luminescent solar concentrators.展开更多
Prime integers and their generalizations play important roles in protocols for secure transmission of information via open channels of telecommunication networks. Generation of multidigit large primes in the design st...Prime integers and their generalizations play important roles in protocols for secure transmission of information via open channels of telecommunication networks. Generation of multidigit large primes in the design stage of a cryptographic system is a formidable task. Fermat primality checking is one of the simplest of all tests. Unfortunately, there are composite integers (called Carmichael numbers) that are not detectable by the Fermat test. In this paper we consider modular arithmetic based on complex integers;and provide several tests that verify the primality of real integers. Although the new tests detect most Carmichael numbers, there are a small percentage of them that escape these tests.展开更多
Triplets are seldom and monozygotic triplets are scarcely seen in humanity. There are few reports on triplets at home and abroad and diagnosis of zygosity is rarely made. We did the analysis of clinical material on tw...Triplets are seldom and monozygotic triplets are scarcely seen in humanity. There are few reports on triplets at home and abroad and diagnosis of zygosity is rarely made. We did the analysis of clinical material on two sets of triplets. Diagnosis and analysis of zygosity were made in eleven ways about 57 items including blood type and RBC enzyme type, etc.展开更多
Molecular triplets have attracted great interest across multidisciplinary fields of the research ranging from thermally activated delayed fluorescence[1],triplet-triplet annihilation(TTA)upconversion[2],to photodynami...Molecular triplets have attracted great interest across multidisciplinary fields of the research ranging from thermally activated delayed fluorescence[1],triplet-triplet annihilation(TTA)upconversion[2],to photodynamic therapy relying on TTA between triplet photosensitizers and surrounding triplet oxygen to generate singlet oxygen species[3].展开更多
Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial...Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial insights that aid medicinal chemists in optimizing molecular structures.Nonetheless,they also form a major source of prediction error in structure-activity relationship(SAR)models.To date,several studies have demonstrated that deep neural networks based on molecular images or graphs might need to be improved further in predicting the potency of ACs.In this paper,we integrated the triplet loss in face recognition with pre-training strategy to develop a prediction model ACtriplet,tailored for ACs.Through extensive comparison with multiple baseline models on 30 benchmark datasets,the results showed that ACtriplet was significantly better than those deep learning(DL)models without pretraining.In addition,we explored the effect of pre-training on data representation.Finally,the case study demonstrated that our model's interpretability module could explain the prediction results reasonably.In the dilemma that the amount of data could not be increased rapidly,this innovative framework would better make use of the existing data,which would propel the potential of DL in the early stage of drug discovery and optimization.展开更多
Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversi...Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversion(TTA-UC), respectively. It turned out that the pyridine cation served as a mask for the excited state of the sensitizer, the triplet states of S-2 and S-3 were significantly quenched by photo-induced electron transfer(PET) with phosphorescence quantum yield quenched from 24.4% for S-4 to 9.3% for S-3,and therefore, both S-2 and S-3 led to negligible UC emissions when traditional annihilator DPA was used as the annihilator. Delightfully, when supramolecular annihilator A-1 and A-2 were employed to include the pyridine cation, PET was significantly inhibited and the triplet states of the sensitizers were activated,TTA-UC emission was therefore boosted. The UC quantum yield of A-2/S-3 system was up to 130 times higher than that of DPA/S-3 system, and the UC emission was switchable by the addition of competitive vips.展开更多
AuCu bimetallic nanoclusters exhibit enhanced emission relative to structurally analogous Au nanoclusters,though their excited-state dynamics remains incompletely characterized.Here,we chose AuCu_(14)as a system to pr...AuCu bimetallic nanoclusters exhibit enhanced emission relative to structurally analogous Au nanoclusters,though their excited-state dynamics remains incompletely characterized.Here,we chose AuCu_(14)as a system to probe the excited-state behaviors and triplet energy transfer dynamics of bimetallic nanoclusters.The O_(2)sensitivity of both photoluminescence quantum yield and excited-state lifetime confirms triplet-origin emission,while the minimal spectral changes at low temperature suggest weak electron-vibration coupling.Notably,although O_(2)induces significant photoluminescence quenching,the addition of triplet-state acceptors(perylene and anthracene)shows no quenching effect due to steric hindrance from surface ligands.These results advance the mechanistic understanding of triplet-state dynamics in AuCu bimetallic nanoclusters.展开更多
A heavy-ion time-of-flight spectrometer called HiToF,with magnet focusing accomplished by a quadrupole triplet lens,was constructed at the Beijing Tandem Accelerator National Laboratory,mainly for studies of multi-nuc...A heavy-ion time-of-flight spectrometer called HiToF,with magnet focusing accomplished by a quadrupole triplet lens,was constructed at the Beijing Tandem Accelerator National Laboratory,mainly for studies of multi-nucleon transfer reactions at energies near the Coulomb barrier.The spectrometer was equipped with a rotating chamber with a diameter of 40 cm and could be rotated over a large angular range from−40◦to 160◦.The length from the target to the focal plane is 2.7 m,enabling high-precision time-of-flight measurements using two microchannel plate detectors with a 1.9 m apart and a typical time resolution of 120 ps.A multisampling position-sensitive ionization chamber forΔE−E measurement is placed on the focal plane,which offers aΔZ∕Z resolution of 1/50.The setup provided a maximum solid angleΔΩ=20 msr.An experiment on^(32)S+^(90,94)Zr at a beam energy of 135 MeV was performed to test the performance.The projectile-like ions were identified with a mass resolution ofσ=0.2 amu.The results showed that the HiToF spectrometer is a powerful setup for studying heavy-ion reaction mechanisms at low energies.展开更多
Localized surface plasmon resonance(LSPR)effects in gold nanoparticles(AuNPs)significantly influence the excited states of nearby molecules,offering unique opportunities for enhancing molecular triplet states.Herein,w...Localized surface plasmon resonance(LSPR)effects in gold nanoparticles(AuNPs)significantly influence the excited states of nearby molecules,offering unique opportunities for enhancing molecular triplet states.Herein,we report the synthesis of DNA-templated gold nanostars(AuNF_A15)and gold nanospheres(AuNS_T15)via a seed-mediated growth method and their ability to enhance the triplet state of coralyne,a small molecule with promising applications in photodynamic therapy(PDT).DNA single strands(A15 or T15)were employed as templates to regulate the morphology of AuNPs,resulting in nanostars and nanospheres.The nanostars exhibited a superior LSPR effect due to their“lightning rod effect",significantly enhancing coralyne’s triplet signal by 15-fold compared to a 10-fold enhancement observed with nanospheres.This enhancement was confirmed via steady-state and nanosecond transient absorption spectroscopy.These findings demonstrate that DNA-assembled gold nanostars hold exceptional potential for enhancing molecular triplet states,particularly for PDT applications involving DNA-targeting small molecules.展开更多
基金supported by Chinese Postdoctoral Science Foundation (2021M692696)the National Science and Technology Project (2016ZX05058-003-017)Sichuan Science and Technology Program (2021YFH0081)。
文摘This work aimed at investigating the crucial factor in building and maintaining the combustion front during in-situ combustion(ISC),oxidized coke and pyrolyzed coke.The surface morphologies,elemental contents,and non-isothermal mass losses of the oxidized and pyrolyzed cokes were thoroughly examined.The results indicated that the oxidized coke could be combusted at a lower temperature compared to the pyrolyzed coke due primarily to their differences in the molecular polarity and microstructure.Kinetic triplets of coke combustion were determined using iso-conversional models and one advanced integral master plots method.The activation energy values of the oxidized and pyrolyzed cokes varied in the range of 130-153 k J/mol and 95-120 kJ/mol,respectively.The most appropriate reaction model of combustion of the oxidized and pyrolyzed cokes followed three-dimensional diffusion model(D_(3)) and random nucleation and subsequent growth model(F_(1)),respectively.These observations assisted in building the numerical model of these two types of cokes to simulate the ISC process.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11702034,11702218,and 11421062)Fundamental Research Funds for the Central Universities,China(Grant Nos.310812171011 and G2016KY0305)the National Key Project of Magneto-Constrained Fusion Energy Development Program,China(Grant No.2013GB110002)
文摘We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL)theory.Compared with the regular square array of circular holes,the vortices are no longer pinned inside the circular holes,but instead stabilized at the center of the antidot triplets depending on the geometry parameters.Moreover,the influences of the geometry parameters and the polarity of the applied current on the current–voltage(I–V)characteristics are also studied.The critical current for the sample turning into a normal state becomes smaller when the hole diameter D is smaller and the spacing B between the holes is larger.Due to the asymmetric pinning sites,our numerical simulations demonstrate that the positive and negative rectified voltages appear alternately in the resistive state of the sample under an ac current of square pulses.
基金Project supported by the National Natural Science Foundation of China(Grant No.61605249)the Science and Technology Key Project of Henan Province of China(Grant Nos.182102210577 and 232102211086).
文摘Quantum light sources are the core resources for photonics-based quantum information processing.We investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversion in micro/nanofiber.The phase mismatching at one-third pump frequency gives rise to non-degenerate photon triplets,the joint spectral intensity of which has an elliptical locus with a fixed eccentricity of√6/3.Therefore,we propose a frequency-division scheme to separate non-degenerate photon triplets into three channels with high heralding efficiency for the first time.Choosing an appropriate pump wavelength can compensate for the fabrication errors of micro/nanofiber and also generate narrowband,non-degenerate photon triplet sources with a high signal-to-noise ratio.Furthermore,the long-period micro/nanofiber grating introduces a new controllable degree of freedom to tailor phase matching,resulting from the periodic oscillation of dispersion.In this scheme,the wavelength of photon triplets can be flexibly tuned using quasi-phase matching.We study the generation of photon triplets from this novel perspective of spectrum engineering,and we believe that this work will accelerate the practical implementation of photon triplets in quantum information processing.
基金This work was supported by the National Nature Foundation of China (No. 597905006).
文摘The electroluminescence (EL) produced by a highly luminescent phosphorescent dye Cu-4(CdropCPh)(4)L-2 (L = 1.8-bis(di-phenylphosphino)-3,6-dioxaoctane, Cu-4) doped polymer as emitting layer is reported. The effects of the charge injection balance on the polymers, in particular, poly(N-vinylcarbazole) (PVK) have been studied by using photoluminescence and electroluminescence spectroscopy. Changes in the emission spectra demonstrate the influence of the charge injection balance on the formation ratio of triplet and singlet excitons. This provides a new technical approach to realize the color patterning in polymer LEDs.
基金This work is supported by the National Natural Science Foundation of China(No.21803070).
文摘Sensitizing molecular triplets by colloidal nanocrystals via triplet energy transfer is important for applications such as upconversion or organic synthesis.Typically two step triplet energy transfer(TET)are included in these applications:firstly the triplet energy stored in nanocrystals are extracted into surface ligands,and then the ligands further transfer triplet energy into molecules in bulk solution.Here we report one-step TET application from CsPbBr_(3) perovskite nanocrystals(NCs)to surface-anchored metalloporphyrin derivative molecules(MP).Compared to conventional two-step TET,the one-step TET mechanism possess lower energy loss and higher TET efficiency which is more generally implementable.In this scheme,photoexcitation of CsPbBr_(3)NCs leads to the sensitization of MP ligands triplets which efficiently emit phosphorescence.The enhanced light absorption of MP ligands and down-shifted photon emission can be useful in devices such as luminescent solar concentrators.
文摘Prime integers and their generalizations play important roles in protocols for secure transmission of information via open channels of telecommunication networks. Generation of multidigit large primes in the design stage of a cryptographic system is a formidable task. Fermat primality checking is one of the simplest of all tests. Unfortunately, there are composite integers (called Carmichael numbers) that are not detectable by the Fermat test. In this paper we consider modular arithmetic based on complex integers;and provide several tests that verify the primality of real integers. Although the new tests detect most Carmichael numbers, there are a small percentage of them that escape these tests.
文摘Triplets are seldom and monozygotic triplets are scarcely seen in humanity. There are few reports on triplets at home and abroad and diagnosis of zygosity is rarely made. We did the analysis of clinical material on two sets of triplets. Diagnosis and analysis of zygosity were made in eleven ways about 57 items including blood type and RBC enzyme type, etc.
文摘Molecular triplets have attracted great interest across multidisciplinary fields of the research ranging from thermally activated delayed fluorescence[1],triplet-triplet annihilation(TTA)upconversion[2],to photodynamic therapy relying on TTA between triplet photosensitizers and surrounding triplet oxygen to generate singlet oxygen species[3].
基金supported by the National Natural Science Foundation of China(Grant Nos.:U23A20530,82273858,and 82173746)the National Key Research and Development Programof China(Grant No.:2023YFF1204904)Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism(Shanghai Municipal Education Commission,China).
文摘Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial insights that aid medicinal chemists in optimizing molecular structures.Nonetheless,they also form a major source of prediction error in structure-activity relationship(SAR)models.To date,several studies have demonstrated that deep neural networks based on molecular images or graphs might need to be improved further in predicting the potency of ACs.In this paper,we integrated the triplet loss in face recognition with pre-training strategy to develop a prediction model ACtriplet,tailored for ACs.Through extensive comparison with multiple baseline models on 30 benchmark datasets,the results showed that ACtriplet was significantly better than those deep learning(DL)models without pretraining.In addition,we explored the effect of pre-training on data representation.Finally,the case study demonstrated that our model's interpretability module could explain the prediction results reasonably.In the dilemma that the amount of data could not be increased rapidly,this innovative framework would better make use of the existing data,which would propel the potential of DL in the early stage of drug discovery and optimization.
基金supported by the National Natural Science Foundation of China (Nos. 22171194, 21971169, 92056116 and 21871194)the Fundamental Research Funds for the Central Universities (No. 20826041D4117)the Science & Technology Department of Sichuan Province (Nos. 2022YFH0095 and 2021ZYD0052)。
文摘Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversion(TTA-UC), respectively. It turned out that the pyridine cation served as a mask for the excited state of the sensitizer, the triplet states of S-2 and S-3 were significantly quenched by photo-induced electron transfer(PET) with phosphorescence quantum yield quenched from 24.4% for S-4 to 9.3% for S-3,and therefore, both S-2 and S-3 led to negligible UC emissions when traditional annihilator DPA was used as the annihilator. Delightfully, when supramolecular annihilator A-1 and A-2 were employed to include the pyridine cation, PET was significantly inhibited and the triplet states of the sensitizers were activated,TTA-UC emission was therefore boosted. The UC quantum yield of A-2/S-3 system was up to 130 times higher than that of DPA/S-3 system, and the UC emission was switchable by the addition of competitive vips.
基金supported by the National Natural Science Foundation of China(No.22273095).
文摘AuCu bimetallic nanoclusters exhibit enhanced emission relative to structurally analogous Au nanoclusters,though their excited-state dynamics remains incompletely characterized.Here,we chose AuCu_(14)as a system to probe the excited-state behaviors and triplet energy transfer dynamics of bimetallic nanoclusters.The O_(2)sensitivity of both photoluminescence quantum yield and excited-state lifetime confirms triplet-origin emission,while the minimal spectral changes at low temperature suggest weak electron-vibration coupling.Notably,although O_(2)induces significant photoluminescence quenching,the addition of triplet-state acceptors(perylene and anthracene)shows no quenching effect due to steric hindrance from surface ligands.These results advance the mechanistic understanding of triplet-state dynamics in AuCu bimetallic nanoclusters.
基金supported by the National Key R&D Program of China(No.2022YFA1602302)the National Natural Science Foundation of China(Nos.U2167204,12175314,and 12235020)the Continuous-Support Basic Scientific Research Project.
文摘A heavy-ion time-of-flight spectrometer called HiToF,with magnet focusing accomplished by a quadrupole triplet lens,was constructed at the Beijing Tandem Accelerator National Laboratory,mainly for studies of multi-nucleon transfer reactions at energies near the Coulomb barrier.The spectrometer was equipped with a rotating chamber with a diameter of 40 cm and could be rotated over a large angular range from−40◦to 160◦.The length from the target to the focal plane is 2.7 m,enabling high-precision time-of-flight measurements using two microchannel plate detectors with a 1.9 m apart and a typical time resolution of 120 ps.A multisampling position-sensitive ionization chamber forΔE−E measurement is placed on the focal plane,which offers aΔZ∕Z resolution of 1/50.The setup provided a maximum solid angleΔΩ=20 msr.An experiment on^(32)S+^(90,94)Zr at a beam energy of 135 MeV was performed to test the performance.The projectile-like ions were identified with a mass resolution ofσ=0.2 amu.The results showed that the HiToF spectrometer is a powerful setup for studying heavy-ion reaction mechanisms at low energies.
基金supported by the National Natural Science Foundation of China(Nos.21933005,22473014,and 22273007)the National Key R&D Program of China(No.2022YFA1505400).
文摘Localized surface plasmon resonance(LSPR)effects in gold nanoparticles(AuNPs)significantly influence the excited states of nearby molecules,offering unique opportunities for enhancing molecular triplet states.Herein,we report the synthesis of DNA-templated gold nanostars(AuNF_A15)and gold nanospheres(AuNS_T15)via a seed-mediated growth method and their ability to enhance the triplet state of coralyne,a small molecule with promising applications in photodynamic therapy(PDT).DNA single strands(A15 or T15)were employed as templates to regulate the morphology of AuNPs,resulting in nanostars and nanospheres.The nanostars exhibited a superior LSPR effect due to their“lightning rod effect",significantly enhancing coralyne’s triplet signal by 15-fold compared to a 10-fold enhancement observed with nanospheres.This enhancement was confirmed via steady-state and nanosecond transient absorption spectroscopy.These findings demonstrate that DNA-assembled gold nanostars hold exceptional potential for enhancing molecular triplet states,particularly for PDT applications involving DNA-targeting small molecules.
