The ^(13)C T_(1s) of --CH_3 side group in PPU/P (St-co-AA), AB-crosslinked polymers (i. e.ABCP) was studied by using high resolution solid state NMR. The rotation motion of --CH_3 sidegroup in PPU was analyzed by mean...The ^(13)C T_(1s) of --CH_3 side group in PPU/P (St-co-AA), AB-crosslinked polymers (i. e.ABCP) was studied by using high resolution solid state NMR. The rotation motion of --CH_3 sidegroup in PPU was analyzed by means of the average spectral density functions of internal rota-tion. The results showed that the rotation of the --CH_3 side group is related closely to the com-patibility between the two components. The compatibility was studied by analyzing the protonspin-lattice relaxation in rotating frame, spin-spin relaxation and spin-diffusion. The resultsshowed that the hydrogen bonds between the components play a major role in determining thecompatibility. Through spin diffusion studying, the soft phase domain size was calculated. Bystudying proton spin-spin relaxation, the content of each component in each phase and that ofeach phase in the samples can be obtained. The result shows that the content of interphase is related closely to the compatibility.展开更多
The molecular motion in polyepichlorohydrin (PEPCH), in solution and bulk, was studied by high resolution NMR by means of line width, spin-lattice relaxation time T_1 and nuclear Overhauser effect NOE. The results sho...The molecular motion in polyepichlorohydrin (PEPCH), in solution and bulk, was studied by high resolution NMR by means of line width, spin-lattice relaxation time T_1 and nuclear Overhauser effect NOE. The results show that the VJGM model can describe the main chain motion of PEPCH in solution perfectly. In bulk state, the relationship between the line width and the temperature is consistent with WLF equation, but that between the high frequency molecular motion correlation time (in T_1 scale ) and temperature is consistent with Arrhenius equation. The motion parameters of PEPCH in both states were calculated. The internal rotation motion of side—CH_2Cl group was analyzed by using equal three-site jump and diffusion internal rotation model in both states.展开更多
Coinage bonds, a type of noncovalent interaction, occur between group 11elements (Au, Ag, and Cu) with electron donor groups. Despite theoretical validation,empirical evidence remains limited. In this study, an aggreg...Coinage bonds, a type of noncovalent interaction, occur between group 11elements (Au, Ag, and Cu) with electron donor groups. Despite theoretical validation,empirical evidence remains limited. In this study, an aggregation-inducedemission (AIE)-active Au(I) complex, ITCPAu, which exhibits Au⋅⋅⋅I coinagebonds, was revealed based on the single-crystal X-ray diffraction and theoreticalcalculations. Further examination of the luminescence properties of theITCPAu revealed multiswitchable behavior, including mechanochromism and thermochromism.Nearly pure white-light emission was achieved with CommissionInternationale de L’Eclairage (CIE) 1931 chromaticity coordinates of (0.30, 0.31)by grinding the green-emissive ITCPAu monomer crystals. Moreover, visualizationand manipulation of solid-state molecular motion (SSMM) in the yellow-emissiveITCPAu dimer crystals, driven by the robust Au⋅⋅⋅I coinage bonds, were revealedthrough a combination of crystal engineering and luminescent properties. Furthermore,to support the robust Au⋅⋅⋅I coinage bonds, a versatile carrier for small solventmolecules in crystal lattices was developed for uptake and release. Our findings provideexperimental and theoretical evidence for Au⋅⋅⋅I coinage bonds, highlightingtheir ability to boost photoluminescence quantum yield (PLQY) and trigger SSMM,emphasizing their potential in developing smart materials with stimuli-responsiveproperties.展开更多
Restricting molecular motion of fluorophores is the most direct and effective approach to creating highly emissive fluorescent materials.However,attempts to limit molecular motion of conventional fluorophores in aqueo...Restricting molecular motion of fluorophores is the most direct and effective approach to creating highly emissive fluorescent materials.However,attempts to limit molecular motion of conventional fluorophores in aqueous environments often encounter undesired aggregation-caused quenching(ACQ).To address this challenge,this study presents an innovative design of a water-soluble supramolecular scaffold with a rigidmicrodomain,achieved by assembling a cyclic peptide-diblock copolymer conjugate into cylindrical nanoparticles,where the rigid microdomain is provided by the hydrophobic polymer segment with a high glass transition temperature.Supramolecular fluorophores(termed as Supra-fluorophores)are constructed by noncovalently dispersing fluorophores within the rigid microenvironment of the scaffold through a simple coassembly approach,effectively mitigating molecular motion and ACQ.This strategy accommodates a wide range of fluorophores,resulting in Supra-fluorophores with fluorescence quantum yields up to 71.6%and volume-normalized brightness reaching 19,910 M−1 cm−1 nm−3.Furthermore,increased rigidity significantly reduces dynamic exchange among assemblies by three orders of magnitude,thereby generating kinetically trapped Supra-fluorophores that exhibit minimal dye crosstalk upon mixing.This approach demonstrates substantial potential for advanced bioimaging applications,such as multicolor cell labeling,real-time tracking,and high-resolution cellular imaging.展开更多
Ultrahigh dose-rate(FLASH)radiotherapy is an emerging technology with excellent therapeutic effects and low biological toxicity.However,tumor recurrence largely impede the effectiveness of FLASH therapy.Overcoming tum...Ultrahigh dose-rate(FLASH)radiotherapy is an emerging technology with excellent therapeutic effects and low biological toxicity.However,tumor recurrence largely impede the effectiveness of FLASH therapy.Overcoming tumor recurrence is crucial for practical FLASH applications.Here,we prepared an agarose-based thermosensitive hydrogel containing a mild photothermal agent(TPE-BBT)and a glutaminase inhibitor(CB-839).Within nanoparticles,TPE-BBT exhibits aggregation-induced emission peaked at 900 nm,while the unrestricted molecular motions endow TPE-BBT with a mild photothermy generation ability.The balanced photothermal effect and photoluminescence are ideal for phototheranostics.Upon 660-nm laser irradiation,the temperature-rising effect softens and hydrolyzes the hydrogel to release TPE-BBT and CB-839 into the tumor site for concurrent mild photothermal therapy and chemotherapy,jointly inhibiting homologous recombination repair of DNA.The enhanced FLASH radiotherapy efficiently kills the tumor tissue without recurrence and obvious systematic toxicity.This work deciphers the unrestricted molecular motions in bright organic fluorophores as a source of photothermy,and provides novel recurrence-resistant radiotherapy without adverse side effects.展开更多
In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ^(13)C nuclear magnetic...In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ^(13)C nuclear magnetic relaxation. The fully anisotropic overall tumbling motion model with methyl conformation jumps internal rotation among three equivalent sites is presented, and the spectral density function of this model is derived. The rotation rates for overall tumbling motions to ocotillol-type saponins (OTS) are computed by Woessner's fully anisotropic overall tumbling motion model, and the internal rotation rate and barrier for side groups in OTS are calculated using free diffusion internal rotation model, restriction diffusion internal rotation model and conformation jumps internal rotation model, respectively.展开更多
The research on low-dimensional organic-inorganic hybrid metal halide materials is attractive due to their flexible structures and outstanding optoelectronic properties.This paper reports on a series of novel(PIP)CdX_...The research on low-dimensional organic-inorganic hybrid metal halide materials is attractive due to their flexible structures and outstanding optoelectronic properties.This paper reports on a series of novel(PIP)CdX_(4) compounds(PIP=protonated piperazine),including(PIP)CdI_(4)(Cd-I),(PIP)CdI_(2)Cl_(2)(Cd-ICl)and(PIP)CdI_(2.4)Br_(1.6)(Cd-IBr).It is notable that PIP·2Cl can diffuse into their structures resulting in a luminescent phase.展开更多
Since rate effect of materials plays a key role in impact engineering, the microscopic mechanism of rate effect is investigated at molecular level in this paper. The results show that rate effect on the strength of at...Since rate effect of materials plays a key role in impact engineering, the microscopic mechanism of rate effect is investigated at molecular level in this paper. The results show that rate effect on the strength of atomic system is closely related to the coupled evolution of atomic motions and potential landscapes. Accordingly, it becomes possible to develop a new algorithm of molecular simulation, which could properly and efficiently demonstrate strain rate effect under a wide range of loading rates and unveil the mecha- nisms underlying the strain rate effects.展开更多
The collective motion of rounded squares with different comer-roundness ζ is studied by molecular dynamlcs （MD） simulation in this work. Three types of translational collective motion pattern are observed, includin...The collective motion of rounded squares with different comer-roundness ζ is studied by molecular dynamlcs （MD） simulation in this work. Three types of translational collective motion pattern are observed, including＇, gliding, hopping and a mixture of gliding and hopping. Quantitatively, the dynamics of each observed ordered phase is characterized by both mean square displacement and van Hove functions for both translation and rotation. The effect of corner-roundness on the dynamics is further studied by comparing the dynamics of the rhombic crystal phases folmed by different comer-.rounded particles at a same surface fraction. The results show that as ζ increases from 0.286 to 0.667, the translational collective motion of particles changes from a gliding-dominant pattern to a hopping-dominant patte;n, whereas the rotational motion pattern is hopping-like and does not change in its type, but the rotational hopping becomes much more frequent as increases （i.e., as particles become more rounded）. A simple geometrical model is proposed to explain the trend of gliding motion observed in MD simulations.展开更多
合成了3种可聚合的1,8-萘酰亚胺衍生物,并研究了其在二甲基亚砜(DMSO)溶液中的光物理性质.这些化合物表现出的光物理性质与其电子环境有关.通过溶胶-凝胶法制备了可聚合1,8-萘酰亚胺衍生物与硅氧烷的共聚物.尽管3种萘酰亚胺衍生物C-4位...合成了3种可聚合的1,8-萘酰亚胺衍生物,并研究了其在二甲基亚砜(DMSO)溶液中的光物理性质.这些化合物表现出的光物理性质与其电子环境有关.通过溶胶-凝胶法制备了可聚合1,8-萘酰亚胺衍生物与硅氧烷的共聚物.尽管3种萘酰亚胺衍生物C-4位的取代基不同,但在3-氨丙基三乙氧基硅烷(APTES)固凝胶中摩尔分数为0.06%时荧光强度均最大.利用29Si MAS NMR对合成材料进行了表征,结果表明,硅氧烷的缩聚程度影响材料的荧光强度,说明材料中荧光单元的分子运动对材料的荧光性能有重要影响.展开更多
基金The project was supported by the National Natural Science Foundation of China
文摘The ^(13)C T_(1s) of --CH_3 side group in PPU/P (St-co-AA), AB-crosslinked polymers (i. e.ABCP) was studied by using high resolution solid state NMR. The rotation motion of --CH_3 sidegroup in PPU was analyzed by means of the average spectral density functions of internal rota-tion. The results showed that the rotation of the --CH_3 side group is related closely to the com-patibility between the two components. The compatibility was studied by analyzing the protonspin-lattice relaxation in rotating frame, spin-spin relaxation and spin-diffusion. The resultsshowed that the hydrogen bonds between the components play a major role in determining thecompatibility. Through spin diffusion studying, the soft phase domain size was calculated. Bystudying proton spin-spin relaxation, the content of each component in each phase and that ofeach phase in the samples can be obtained. The result shows that the content of interphase is related closely to the compatibility.
基金The project was supported by the National Natural Science Foundation of China
文摘The molecular motion in polyepichlorohydrin (PEPCH), in solution and bulk, was studied by high resolution NMR by means of line width, spin-lattice relaxation time T_1 and nuclear Overhauser effect NOE. The results show that the VJGM model can describe the main chain motion of PEPCH in solution perfectly. In bulk state, the relationship between the line width and the temperature is consistent with WLF equation, but that between the high frequency molecular motion correlation time (in T_1 scale ) and temperature is consistent with Arrhenius equation. The motion parameters of PEPCH in both states were calculated. The internal rotation motion of side—CH_2Cl group was analyzed by using equal three-site jump and diffusion internal rotation model in both states.
基金National Key R&D Program of China,Grant/Award Number:2022YFE0104100National Natural Science Foundation of China,Grant/Award Number:52073242+9 种基金Research Institute for Smart Energy(CDAQ)Research Centre for Nanoscience and Nanotechnology(CE2H)Research Centre for Carbon-Strategic Catalysis(CE2L)Miss Clarea Au for the Endowed Professorship in Energy,Grant/Award Number:847SHong Kong Research Grants Council,Grant/Award Numbers:PolyU 153053/20P,PolyU 25301524Guangdong Provincial Natural Science Foundation-General Project,Grant/Award Number:2024A1515010422PolyU,Grant/Award Numbers:WZ0Z,BEBA,CDB5,CE2NPolyU Shenzhen Research InstituteBaichengbaiyuan special launchInnovation and Technology Commission,Grant/Award Number:ITC-CNERC14SC01。
文摘Coinage bonds, a type of noncovalent interaction, occur between group 11elements (Au, Ag, and Cu) with electron donor groups. Despite theoretical validation,empirical evidence remains limited. In this study, an aggregation-inducedemission (AIE)-active Au(I) complex, ITCPAu, which exhibits Au⋅⋅⋅I coinagebonds, was revealed based on the single-crystal X-ray diffraction and theoreticalcalculations. Further examination of the luminescence properties of theITCPAu revealed multiswitchable behavior, including mechanochromism and thermochromism.Nearly pure white-light emission was achieved with CommissionInternationale de L’Eclairage (CIE) 1931 chromaticity coordinates of (0.30, 0.31)by grinding the green-emissive ITCPAu monomer crystals. Moreover, visualizationand manipulation of solid-state molecular motion (SSMM) in the yellow-emissiveITCPAu dimer crystals, driven by the robust Au⋅⋅⋅I coinage bonds, were revealedthrough a combination of crystal engineering and luminescent properties. Furthermore,to support the robust Au⋅⋅⋅I coinage bonds, a versatile carrier for small solventmolecules in crystal lattices was developed for uptake and release. Our findings provideexperimental and theoretical evidence for Au⋅⋅⋅I coinage bonds, highlightingtheir ability to boost photoluminescence quantum yield (PLQY) and trigger SSMM,emphasizing their potential in developing smart materials with stimuli-responsiveproperties.
基金the assistance of SUSTech Core Research Facilities,and CSNS for the allocation of beam time(grant nos.P0121122200005 and P0124052700001).
文摘Restricting molecular motion of fluorophores is the most direct and effective approach to creating highly emissive fluorescent materials.However,attempts to limit molecular motion of conventional fluorophores in aqueous environments often encounter undesired aggregation-caused quenching(ACQ).To address this challenge,this study presents an innovative design of a water-soluble supramolecular scaffold with a rigidmicrodomain,achieved by assembling a cyclic peptide-diblock copolymer conjugate into cylindrical nanoparticles,where the rigid microdomain is provided by the hydrophobic polymer segment with a high glass transition temperature.Supramolecular fluorophores(termed as Supra-fluorophores)are constructed by noncovalently dispersing fluorophores within the rigid microenvironment of the scaffold through a simple coassembly approach,effectively mitigating molecular motion and ACQ.This strategy accommodates a wide range of fluorophores,resulting in Supra-fluorophores with fluorescence quantum yields up to 71.6%and volume-normalized brightness reaching 19,910 M−1 cm−1 nm−3.Furthermore,increased rigidity significantly reduces dynamic exchange among assemblies by three orders of magnitude,thereby generating kinetically trapped Supra-fluorophores that exhibit minimal dye crosstalk upon mixing.This approach demonstrates substantial potential for advanced bioimaging applications,such as multicolor cell labeling,real-time tracking,and high-resolution cellular imaging.
基金supported by the National Natural Science Foundation of China (21788102 and 82303797)the Research Grants Council of Hong Kong (16306620,16303221,N_HKUST609/19,and C6014-20W)+4 种基金the Research Grants Council of the Hong Kong Special Administrative Region,China (HKUST PDFS2324-6S01)the Innovation and Technology Commission (ITC-CNERC14SC01 and ITCPD/17-9)the Science Technology Innovation Commission of Shenzhen Municipality (KQTD20210811090142053 and GJHZ20210705141810031)the Science and Technology Plan of Shenzhen (JCYJ20200109110608167 and JCYJ20220818103007014)the Guangxi Natural Science Foundation (2023GXNSFBA026137).
文摘Ultrahigh dose-rate(FLASH)radiotherapy is an emerging technology with excellent therapeutic effects and low biological toxicity.However,tumor recurrence largely impede the effectiveness of FLASH therapy.Overcoming tumor recurrence is crucial for practical FLASH applications.Here,we prepared an agarose-based thermosensitive hydrogel containing a mild photothermal agent(TPE-BBT)and a glutaminase inhibitor(CB-839).Within nanoparticles,TPE-BBT exhibits aggregation-induced emission peaked at 900 nm,while the unrestricted molecular motions endow TPE-BBT with a mild photothermy generation ability.The balanced photothermal effect and photoluminescence are ideal for phototheranostics.Upon 660-nm laser irradiation,the temperature-rising effect softens and hydrolyzes the hydrogel to release TPE-BBT and CB-839 into the tumor site for concurrent mild photothermal therapy and chemotherapy,jointly inhibiting homologous recombination repair of DNA.The enhanced FLASH radiotherapy efficiently kills the tumor tissue without recurrence and obvious systematic toxicity.This work deciphers the unrestricted molecular motions in bright organic fluorophores as a source of photothermy,and provides novel recurrence-resistant radiotherapy without adverse side effects.
基金Project supported by the National Natural Science Foundation of China and the State Key Laboratory of Applied Organic Chemistry, Lanzhou University.
文摘In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ^(13)C nuclear magnetic relaxation. The fully anisotropic overall tumbling motion model with methyl conformation jumps internal rotation among three equivalent sites is presented, and the spectral density function of this model is derived. The rotation rates for overall tumbling motions to ocotillol-type saponins (OTS) are computed by Woessner's fully anisotropic overall tumbling motion model, and the internal rotation rate and barrier for side groups in OTS are calculated using free diffusion internal rotation model, restriction diffusion internal rotation model and conformation jumps internal rotation model, respectively.
基金supported by the National Natural Science Foundation of China(22373014)the Natural Science Foundation of Fujian Province(2022J06019).
文摘The research on low-dimensional organic-inorganic hybrid metal halide materials is attractive due to their flexible structures and outstanding optoelectronic properties.This paper reports on a series of novel(PIP)CdX_(4) compounds(PIP=protonated piperazine),including(PIP)CdI_(4)(Cd-I),(PIP)CdI_(2)Cl_(2)(Cd-ICl)and(PIP)CdI_(2.4)Br_(1.6)(Cd-IBr).It is notable that PIP·2Cl can diffuse into their structures resulting in a luminescent phase.
基金supported by the National Basic Research Program of China (973 Program)(2012CB937500)the National Natural Science Foundation of China (11202212,10932011,11021262,11172024,11172305,and 11232013)
文摘Since rate effect of materials plays a key role in impact engineering, the microscopic mechanism of rate effect is investigated at molecular level in this paper. The results show that rate effect on the strength of atomic system is closely related to the coupled evolution of atomic motions and potential landscapes. Accordingly, it becomes possible to develop a new algorithm of molecular simulation, which could properly and efficiently demonstrate strain rate effect under a wide range of loading rates and unveil the mecha- nisms underlying the strain rate effects.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21573159 and 21621004)
文摘The collective motion of rounded squares with different comer-roundness ζ is studied by molecular dynamlcs （MD） simulation in this work. Three types of translational collective motion pattern are observed, including＇, gliding, hopping and a mixture of gliding and hopping. Quantitatively, the dynamics of each observed ordered phase is characterized by both mean square displacement and van Hove functions for both translation and rotation. The effect of corner-roundness on the dynamics is further studied by comparing the dynamics of the rhombic crystal phases folmed by different comer-.rounded particles at a same surface fraction. The results show that as ζ increases from 0.286 to 0.667, the translational collective motion of particles changes from a gliding-dominant pattern to a hopping-dominant patte;n, whereas the rotational motion pattern is hopping-like and does not change in its type, but the rotational hopping becomes much more frequent as increases （i.e., as particles become more rounded）. A simple geometrical model is proposed to explain the trend of gliding motion observed in MD simulations.
文摘合成了3种可聚合的1,8-萘酰亚胺衍生物,并研究了其在二甲基亚砜(DMSO)溶液中的光物理性质.这些化合物表现出的光物理性质与其电子环境有关.通过溶胶-凝胶法制备了可聚合1,8-萘酰亚胺衍生物与硅氧烷的共聚物.尽管3种萘酰亚胺衍生物C-4位的取代基不同,但在3-氨丙基三乙氧基硅烷(APTES)固凝胶中摩尔分数为0.06%时荧光强度均最大.利用29Si MAS NMR对合成材料进行了表征,结果表明,硅氧烷的缩聚程度影响材料的荧光强度,说明材料中荧光单元的分子运动对材料的荧光性能有重要影响.
