This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with ...This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with particular emphasis on the influence of different two-dimensional incident angles on phase delay behavior.Building upon the calibration of phase delay under normal incidence,a phase delay calibra-tion model was developed to account for variations in incident angle and driving voltage.A mathematical re-lationship was established between phase delay and the azimuth angle(α)and pitch angle(β).Experimental validation was conducted under three conditions:α=20°,β=0°;α=0°,β=20°;and an arbitrary angle whereα=5°,β=15°.The results demonstrated that the maximum average deviation between theoretical pre-dictions and experimental measurements did not exceed 0.059 rad.The proposed calibration method proved to be both accurate and practical.This approach offers robust support for LCVR parameter calibration and performance optimization in optical systems,particularly in polarization imaging applications.展开更多
Dimethylphenols serve as important intermediates in synthesizing pharmaceuticals and agrochemicals,yet traditional distillation struggles to separate their isomers due to minimal boiling point differences,and the deve...Dimethylphenols serve as important intermediates in synthesizing pharmaceuticals and agrochemicals,yet traditional distillation struggles to separate their isomers due to minimal boiling point differences,and the development of melt crystallization is hampered by lacking solid–liquid equilibrium (SLE) data for some isomers.Therefore,the SLE data of both binary and ternary mixtures of 2,3-dimethylphenol (2,3-DMP),3,5-dimethylphenol (3,5-DMP),and 3,4-dimethylphenol (3,4-DMP) were determined by using differential scanning calorimetry in this work.Additionally,crystallographic analysis was conducted to investigate the thermodynamic characteristics of these mixtures.The experimental results indicated that all the systems investigated in this research exhibited eutectic behavior.The experimentally obtained SLE data were well correlated with the Wilson and non-random two-liquid models.The excess thermodynamic functions were calculated to analyze the types and intensities of the molecular interactions occurring in the mixtures.Furthermore,this study developed a model for the correlation between the theoretical crystallization yield and the actual cooling yield and final yield in melt crystallization.This study has furnished reliable data essential for developing and optimizing the melt crystallization process of mixtures of 2,3-DMP,3,5-DMP,and 3,4-DMP.展开更多
The doped quantum spin liquid on the kagome lattice provides a fascinating platform to explore exotic quantum states,such as the reported holon Wigner crystal at low doping.By extending the doping range toδ=0.027–0....The doped quantum spin liquid on the kagome lattice provides a fascinating platform to explore exotic quantum states,such as the reported holon Wigner crystal at low doping.By extending the doping range toδ=0.027–0.36,we studied the kagome-lattice t-J model using state-of-the-art density matrix renormalization group calculations.On the L_(y)=3 cylinder(Ly is the number of unit cells along the circumferential direction),we established a quantum phase diagram with an increasing doping level.In addition to the charge density wave states at lower doping levels,we found an emergent Fermi-liquid-like phase by melting the holon Wigner crystal at δ≈0.15,which is characterized by the suppression of charge density oscillation and power-law decay of various correlation functions.For a wider L_(y)=4 cylinder,the bond-dimension extrapolated correlation functions also support such a Fermi-liquid-like state,suggesting its stability with increasing system size.In a narrow doping range near δ=1/3 for the L_(y)=3 cylinder,we find a state with an exponential decay of the single-particle correlation,but the other correlation functions preserve the features in the Fermi-liquid-like phase,which may be a precursor of a superconducting state.Nevertheless,this peculiar state nearδ=1/3 disappears for the L_(y)=4 cylinder,implying a possible lattice-size dependence.Our results reveal quantum melting from a holon Wigner crystal to a Fermi-liquid-like state with increasing hole density and suggest a doping regime to explore superconductivity in future studies.展开更多
The thermotropic liquid crystal polyester(TLCP)fiber is an increasingly important strategic high-performance fiber.In this paper,the TLCP was prepared by two-step melt polymerization using 4-hydroxybenzoic acid(HBA)an...The thermotropic liquid crystal polyester(TLCP)fiber is an increasingly important strategic high-performance fiber.In this paper,the TLCP was prepared by two-step melt polymerization using 4-hydroxybenzoic acid(HBA)and 6-hydroxy-2-naphthoic acid(HNA)as comonomers at a molar ratio of 7∶3.The structure of TLCP was confirmed by the Fourier transform infrared(FTIR)spectrometer and nuclear magnetic resonance(NMR)spectrometer.The thermal and rheological properties of TLCP before and after heat treatment were analyzed systematically by the differential scanning calorimeter(DSC),dynamic mechanical analyzer(DMA)and high-temperature rotational rheometer.The results revealed that the melting temperature,glass transition temperature and melt viscosity of the TLCP increased significantly after heat treatment.It indicates that the crystallization of the TLCP is perfect,and solid-phase condensation occurs during heat treatment,which increases its molecular mass.In conclusion,heat treatment at a temperature below but close to the melting temperature can effectively regulate the structure and properties of the TLCP,and the results of this study can provide a reference for the high strengthening of TLCP fibers.展开更多
Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However...Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However,chromatic aberration remains a serious longstanding problem for diffractive optics,hindering their broader adoption.To overcome the chromatic aberrations for red,green and blue(RGB)light sources,in this paper,we propose a counterintuitive multi-twist structure to achieve narrowband PBOEs without crosstalk,which plays a vital role to eliminate the chromatic aberration.The performance of our designed and fabricated narrowband Pacharatnam-Berry lenses(PBLs)aligns well with our simulation results.Furthermore,in a feasibility demonstration experiment using a laser projector,our proposed PBL system indeed exhibits a diminished chromatic aberration as compared to a broadband PBL.Additionally,polarization raytracing is implemented to demonstrate the versatility of the multi-twist structure for designing any RGB wavelengths with high contrast ratios.This analysis explores the feasibility of using RGB laser lines and quantum dot light-emitting diodes.Overall,our approach enables high optical efficiency,low fabrication complexity,and high degree of design freedom to accommodate any liquid crystal material and RGB light sources,holding immense potential for widespread applications of achromatic PBOEs.展开更多
The liquid crystalline polymers with photosensitive groups can self-assemble.When the polymer film is exposed to linearly polarized ultraviolet(LPUV),it can react a polarization-axis selective photoreaction.A small op...The liquid crystalline polymers with photosensitive groups can self-assemble.When the polymer film is exposed to linearly polarized ultraviolet(LPUV),it can react a polarization-axis selective photoreaction.A small optical anisotropy presented from an axis-selective photoreaction of the photosensitive groups.When annealing in the liquid crystal temperature,a large optical anisotropic change of the polymer film was appeared.In the paper,the photoreaction property of polymer containing coumarin photosensitive group was measured by an ultraviolet spectrum method.The photochemical reaction property corresponding to the different exposure temperature and energy was investigated.The orientation performance at different annealing conditions was also conducted.The results indicated that when the exposure temperature is 70℃and 130℃,ΔA achieve the maximum and the corresponding exposure energy is the minimum.The corresponding DP is around 45%,when the exposure energy is 320 mJ/cm^(2) and 384 mJ/cm^(2),and the annealing temperature is 160℃,the correspondingΔA and S reach the maximum,ΔA=0.22 and S=0.048,respectively.展开更多
This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized ...This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized via the esterification of phytosterol and oleic acid,whose structure was characterized using Fourier-transform infrared spectroscopy(FTIR)and mass spectrometry(MS).Its liquid crystalline behavior was confirmed via the polarized optical microscopy(POM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),wide-angle X-ray scattering(WAXS),and small-angle X-ray scattering(SAXS).UV absorption tests were conducted to assess the UV-blocking performance of the oleic acid sterol ester liquid crystals.To improve the stability of its liquid crystalline structure,the oleic acid sterol ester was encapsulated into microcapsules through the emulsion polymerization.SPF measurements were performed on the sunscreen formulations containing liquid crystal microcapsules.The oleic acid sterol ester displayed cholesteric liquid crystalline behavior and strong UVA absorption,which indicates its suitability as a natural UV absorber.Microencapsulation further enhanced its stability and UV-blocking properties.SPF testing showed that the formulations with microcapsules achieved an SPF value of 7.01,which surpasses the nano titanium dioxide(SPF=6.23)and significantly outperform the unencapsulated liquid crystal formulations(SPF=2.65).This study highlights the potential of microencapsulated oleic acid sterol ester as a novel UV absorber in the sunscreen formulations,offers the enhanced stability and effective UV protection,and showcases its application potential in the innovative cosmetic products.展开更多
The memory behavior in liquid crystals(LCs)that is characterized by low cost,large area,high speed,and high-density memory has evolved from a mere scientific curiosity to a technology that is being applied in a variet...The memory behavior in liquid crystals(LCs)that is characterized by low cost,large area,high speed,and high-density memory has evolved from a mere scientific curiosity to a technology that is being applied in a variety of commodities.In this study,we utilized molybdenum disulfide(MoS_(2))nanoflakes as the vip in a homotropic LCs host to modulate the overall memory effect of the hybrid.It was found that the MoS₂nanoflakes within the LCs host formed agglomerates,which in turn resulted in an accelerated response of the hybrids to the external electric field.However,this process also resulted in a slight decrease in the threshold voltage.Additionally,it was observed that MoS₂nanoflakes in a LCs host tend to align homeotropically under an external electric field,thereby accelerating the refreshment of the memory behavior.The incorporation of a mass fraction of 0.1%2μm MoS₂nanoflakes into the LCs host was found to significantly reduce the refreshing memory behavior in the hybrid to 94.0 s under an external voltage of 5 V.These findings illustrate the efficacy of regulating the rate of memory behavior for a variety of potential applications.展开更多
Soft robots have shown great advantages with simple structure,high degree of freedom,continuous deformation,and benign human-machine interaction.In the past decades,a variety of soft robots,including crawling,jumping,...Soft robots have shown great advantages with simple structure,high degree of freedom,continuous deformation,and benign human-machine interaction.In the past decades,a variety of soft robots,including crawling,jumping,swimming,and climbing robots,have been developed inspired by living creatures.However,most of the reported bionic soft robots have only a single mode of motion,which limits their practical application.Herein,we report a fully 3D printed crawling and flipping soft robot using liquid metal incorporated liquid crystal elastomer(LM-LCE)composite as the actuator.With the application of voltage,liquid metal works as the conductive Joule heating material to induce the contraction of the LCE layer.The bending angle of the LM-LCE composite actuator highly depends on the applied voltage.We further demonstrate that the soft robot can exhibit distinct moving behaviors,such as crawling or flipping,by applying different voltages.The fully 3D printed LM-LCE composite structure provides a strategy for the fast construction of soft robots with diverse motion modes.展开更多
Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and act...Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and actuation behaviors have been obtained in either hydrogels or LCEs,they typically undergo reversible shape change only once(e.g.,one expansion plus one contraction)during one heating/cooling cycle.Herein,we report a study of a novel liquid crystalline hydrogel(LCH)and the achievement of dual actuation in a single heating/cooling cycle by integrating the characteristics of thermoresponsive hydrogel and LCE.The dual actuation behavior arises from the reversible volume phase transition of poly(N-isopropylacrylamide)(PNIPAM)and the reversible order-disorder phase transition of LC mesogens in the LCH.Due to a temperature window separating the two transitions belonging to PNIPAM and LCE,LCH actuator can sequentially execute their respective actuation,thus deforming reversibly twice,during a heating/cooling cycle.The relative actuation degree of the two mechanisms is influenced by the mass ratio of PNIPAM to LCE in the LCH.Moreover,the initial shape of a bilayer actuator made with an active LCH layer and a passive polymer layer can be altered through hydration or dehydration of PNIPAM,which further modifies the dual actuation induced deformation.This work provides an example that shows the interest of developing LCH actuators.展开更多
Polarization,the vector nature of electromagnetic waves,plays a vital role in optics.Polarization is characterized by the amplitude contrast and phase difference between two orthogonal polarization states.The present ...Polarization,the vector nature of electromagnetic waves,plays a vital role in optics.Polarization is characterized by the amplitude contrast and phase difference between two orthogonal polarization states.The present polarimeters usually perform a series of intensity measurements to carry out the polarization detection,making the process bulky and time-consuming.Thereby,compact and broadband-available polarimetry within a single snapshot is urgently demanded.We propose an all-liquid-crystal polarimeter for broadband polarization detection.It is cascaded by a q-plate and a polarization grating.The former is electrically tuned to meet the half-wave condition,whereas the latter is driven to deviate from this condition.After a polarized light passes through this device followed by a polarizer,its amplitude contrast and phase difference between orthogonal spins are read directly from the diffraction pattern.The intensity contrast between±1st orders depicts the amplitude contrast,whereas the rotating angle of the dark split reveals the phase difference.The Stokes parameters can be calculated accordingly.The polarimeter works in a broad spectral range of 470 to 1100 nm.Through presetting a q-plate array,polarization imaging is demonstrated.It supplies an all-liquid-crystal and full-visible-band tunable Stokes polarimeter that significantly promotes advances in polarization optics.展开更多
Recent experiments have found that a liquid crystal elastomer(LCE)rod supported in the middle can rotate continuously under horizontal illumination due to the combined impacts of gravity and light-fueled lateral bend-...Recent experiments have found that a liquid crystal elastomer(LCE)rod supported in the middle can rotate continuously under horizontal illumination due to the combined impacts of gravity and light-fueled lateral bend-ing deformation.Similar to traditional gravity-driven systems,it is constrained by the direction of gravity and cannot be applied in microgravity environments.This study introduces a lateral constraint to a liquid crystal elastomer rod system,enabling self-rotation under lighting from any direction,including horizontal and vertical illumination.Through theoretical modeling,the results indicate that the system can steadily rotate under the combined impacts of lateral forces and vertical illumination.Factors like thermal energy flux,thermal conduc-tivity coefficient,the LCE rod length,contraction coefficient,and friction coefficient affect the angular velocity of the self-rotation.The numerical computations align closely with the experimental data.Our proposed steadily self-rotating system features a simple structure with constant self-rotation.It operates independently of gravity direction,making it an excellent choice for special environments,such as the microgravity conditions on the Moon.The lateral constraint strategy presented in this study offers a general approach to expanding the applica-tions of gravity-driven self-sustained motion,with promising potential,especially in microgravity settings,where its versatility under varying lighting conditions could yield valuable insights.展开更多
In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy ...In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy estimation,we obtain that the trivial solution u=Q=0 is the unique solution.Our theorems correspond to improvements of some recent results and contain some known results as particular cases.展开更多
Conventional liquid crystal elastomer(LCE)-based robots are limited by the need for complex controllers and bulky power supplies,restricting their use in microrobots and soft robots.This paper introduces a novel light...Conventional liquid crystal elastomer(LCE)-based robots are limited by the need for complex controllers and bulky power supplies,restricting their use in microrobots and soft robots.This paper introduces a novel light-powered dicycle that uses an LCE rod,enabling self-rolling by harvesting energy from the environment.The LCE rod serves as the driving force,with energy being supplied by a line light source.Employing a dynamic LCE model,we calculate the transverse curvature of the LCE rod after deformation,as well as the driving moment generated by the shift in a rod’s center of gravity,which allows the dicycle to roll on its own.Through extensive numerical simulations,we identify the correlations between the angular velocity of the dicycle and the key system parameters,specifically the light intensity,LCE rod length,light penetration depth,overall mass of the dicycle,rolling friction coefficient,and wheel radius.Further,the experimental verification is the same as the theoretical result.This proposed light-powered self-rolling dicycle comes with the benefits of the simple structure,the convenient control,the stationary light source,and the small luminous area of the light source.It not only demonstrates self-sustaining oscillations based on active materials,but also highlights the great potential of light-responsive LCE rods in applications such as robotics,aerospace,healthcare,and automation.展开更多
Using the back skin of the mice as the test object,UPLC was used to determine the retention rate of Glabridin(GLA)in the skin and subcutaneous fat pf mice with different dosage forms and different administration times...Using the back skin of the mice as the test object,UPLC was used to determine the retention rate of Glabridin(GLA)in the skin and subcutaneous fat pf mice with different dosage forms and different administration times,and to investigate the transdermal absorption effect of liquid crystal cream.The experimental results showed that the 0.5,1,2,4,6 and 8h skin retention rates of GLA in the liquid crystal cream group were 1.67,0.79,1.73,1.47,1.17 and 1.15 times higher than those of the ordinary cream group under the same dosage of administration,respectively.The 0.5,1,2,4,6 and 8 h fat retention rates of GLA in the normal cream group were 0.86,1.87,1.37,1.20,1.35 and 1.19 times higher than those in the liquid crystal group,respectively.Liquid crystal cream can significantly improve the skin retention of GLA,with certain slow and controlled release,and possesses certain skin targeting properties.展开更多
Liquid crystal elastomers(LCEs)are advanced materials characterized by their rubber-like hyperelasticity and liquid crystal phase transitions,offering exceptional mechanical properties.The development of smart mechani...Liquid crystal elastomers(LCEs)are advanced materials characterized by their rubber-like hyperelasticity and liquid crystal phase transitions,offering exceptional mechanical properties.The development of smart mechanical metamaterials(SMMs)from LCEs expands the potential for controlling mechanical responses and achieving nonlinear behaviors not possible with traditional metamaterials.However,the challenge lies in managing the interplay between nonlinear material responses and structural complexity,making the inverse design of LCE-based SMMs exceptionally demanding.In this paper,we introduce a design framework for LCE smart mechanical metamaterials that leverages neural networks and evolution strategies(ES)to optimize designs with nonlinear mechanical responses.Our approach involves constructing a flexible,unit-cell-based metamaterial model that integrates the soft elastic behavior and thermo-mechanical coupling of LCEs.The combination of microscopic liquid crystal molecule rotation and macroscopic block rotation enables highly tunable and nonlinear mechanical behaviors,of which the precise inverse design of stress-stretch responses is obtained via neural networks combined with ES.In addition,stimuli responses in the liquid crystal elastomers enable real-time adaptability and achieve tailored stress plateaus that are not possible with traditional metamaterials.Our findings provide new pathways in the design and optimization of advanced materials in flexible electronic devices,intelligent actuators,and systems for energy absorption and dissipation.展开更多
Two-dimensional(2D)transition-metal dichalcogenide(TMD)monolayers based on become a promising platform to study photonics and optoelectronics.Electrically controlling the excitonic properties of TMD monolayers can be ...Two-dimensional(2D)transition-metal dichalcogenide(TMD)monolayers based on become a promising platform to study photonics and optoelectronics.Electrically controlling the excitonic properties of TMD monolayers can be realized in different devices.In this work,we realize the strong coupling between the excitons of WS_(2)monolayers and a photonic cavity mode in a liquid crystal microcavity.The formed exciton polaritons can be electrically tuned by applying voltage to the microcavity.Our work offers a way to study exciton-polariton manipulation based on TMD monolayers by electrical methods at room temperature.展开更多
Liquid crystal emulsifiers are widely used in skincare formulations due to their unique structural properties.In formulation development,components such as thickeners,oils,and co-emulsifiers significantly affect liqui...Liquid crystal emulsifiers are widely used in skincare formulations due to their unique structural properties.In formulation development,components such as thickeners,oils,and co-emulsifiers significantly affect liquid crystal formation.Using polyglyceryl-10 stearate as an emulsifier,we investigated the effects of thickeners,oils,higher alcohols,and fatty acids on liquid crystal structure through controlled single-factor experiments.The results showed that xanthan gum(thickener),pentaerythrityl tetraisostearate(oil),and cetearyl alcohol(higher alcohol)produced optimal liquid crystal formation,with fatty acids providing additional benefits.Homogenization speed had the most pronounced impact-both excessively high and low speeds negatively affected the liquid crystal structure.展开更多
This work proposes a bioinspired hierarchical actuation strategy based on liquid crystal elastomers(LCEs),inspired by the helical topological dynamic adaptation mechanism of plant tendrils,to overcome the bottleneck o...This work proposes a bioinspired hierarchical actuation strategy based on liquid crystal elastomers(LCEs),inspired by the helical topological dynamic adaptation mechanism of plant tendrils,to overcome the bottleneck of precise anisotropic control in LCEs.Mechanically pre-programmed hierarchical LCE structures responsive to near-infrared(NIR)light were fabricated:the oriented constrained actuator achieves asymmetric contraction under NIR irradiation,enabling reversible switching between helix and planar morphologies with multi-terrain grasping capability;the biomimetic vine-like helical actuator,composed of Ag nanowire photothermal layers combined with helical LCE,utilizes temperaturegradient-induced phase transition wave propagation to achieve NIR-controlled climbing motion;the M?bius topology actuator realizes reversible deformation or self-locking states by tuning the twist angle(180°/360°);based on these,a bioinspired koala-like concentric soft robot was constructed,successfully demonstrating tree trunk climbing.This study reveals that artificial helical stretching significantly enhances the molecular chain orientation of LCEs(surpassing uniaxial stretching),reaching up to 1000%pre-strain,and the Ag NWs/LCE/PI(Polyimide)tri-layer structure achieves efficient photothermal-mechanical energy conversion via localized surface plasmon resonance(LSPR).This study provides a new paradigm for soft robotics material design and topological programming,demonstrating the potential for remote operation and adaptive grasping.展开更多
Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid cryst...Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid crystal elastomer(LCE)pillar arrays are capable of exhibiting significant and reversible anisotropic deformation under cyclic heating and cooling,showing great potential in tunable adhesion,soft robots,and biomedical devices.However,scaling up LCE pillar manufacturing remains challenging,limiting its practical applications.In this work,a solventfree LCE resin is developed with unique features including simple operating procedure,short fabrication time,and tunable responsive temperature,enabling rapid and large-scale production of LCE pillar arrays.The LCE resin allows for the preparation of complex 3D shapes in addition to film or specimen.The fabrication time can be as short as 4 h,without the need to evaporate solvent.Moreover,the LCE resins can be adjusted with a variable phase transition temperature range from 49.4℃ to 97.7℃ by incorporating non-liquid crystal acrylate chains.The resulting active pillar array structure can undertake sequential actuation upon heating with the tunable actuation temperature.Finally,the application of these pillar arrays in multi-level information encryption is demonstrated.The LCE pillar structure introduced here offers a new strategy for constructing advanced active LCE structures with tunable responsive behavior.展开更多
文摘This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with particular emphasis on the influence of different two-dimensional incident angles on phase delay behavior.Building upon the calibration of phase delay under normal incidence,a phase delay calibra-tion model was developed to account for variations in incident angle and driving voltage.A mathematical re-lationship was established between phase delay and the azimuth angle(α)and pitch angle(β).Experimental validation was conducted under three conditions:α=20°,β=0°;α=0°,β=20°;and an arbitrary angle whereα=5°,β=15°.The results demonstrated that the maximum average deviation between theoretical pre-dictions and experimental measurements did not exceed 0.059 rad.The proposed calibration method proved to be both accurate and practical.This approach offers robust support for LCVR parameter calibration and performance optimization in optical systems,particularly in polarization imaging applications.
基金funded by the National Natural Science Foundation of China(22308358,22208346,22421003)IPE Project for Frontier Basic Research(QYJC-2023-05)CAS Project for Young Scientists in Basic Research(YSBR-038).
文摘Dimethylphenols serve as important intermediates in synthesizing pharmaceuticals and agrochemicals,yet traditional distillation struggles to separate their isomers due to minimal boiling point differences,and the development of melt crystallization is hampered by lacking solid–liquid equilibrium (SLE) data for some isomers.Therefore,the SLE data of both binary and ternary mixtures of 2,3-dimethylphenol (2,3-DMP),3,5-dimethylphenol (3,5-DMP),and 3,4-dimethylphenol (3,4-DMP) were determined by using differential scanning calorimetry in this work.Additionally,crystallographic analysis was conducted to investigate the thermodynamic characteristics of these mixtures.The experimental results indicated that all the systems investigated in this research exhibited eutectic behavior.The experimentally obtained SLE data were well correlated with the Wilson and non-random two-liquid models.The excess thermodynamic functions were calculated to analyze the types and intensities of the molecular interactions occurring in the mixtures.Furthermore,this study developed a model for the correlation between the theoretical crystallization yield and the actual cooling yield and final yield in melt crystallization.This study has furnished reliable data essential for developing and optimizing the melt crystallization process of mixtures of 2,3-DMP,3,5-DMP,and 3,4-DMP.
基金supported by the National Natural Science Foundation of China (Grant Nos.12274014 and 12534009)the Guangdong Provincial Quantum Science Strategic Initiative (Grant No.GDZX2501006)+4 种基金the Special Project in Key Areas for Universities in Guangdong Province (Grant No.2023ZDZX3054)the Dongguan Key Laboratory of Artificial Intelligence Design for Advanced Materialssupported by the U.S.Department of Energy,Office of Basic Energy Sciences (Grant No.DE-FG02-06ER46305) for DMRG studies on unconventional superconductivitysupported by the SongShan Lake HPC Center (SSL-HPC) at Great Bay University (X.Y.J.and S.S.G.)supported in part by the US National Science Foundation (Grant No.DMR-2406524) (D.N.S.)。
文摘The doped quantum spin liquid on the kagome lattice provides a fascinating platform to explore exotic quantum states,such as the reported holon Wigner crystal at low doping.By extending the doping range toδ=0.027–0.36,we studied the kagome-lattice t-J model using state-of-the-art density matrix renormalization group calculations.On the L_(y)=3 cylinder(Ly is the number of unit cells along the circumferential direction),we established a quantum phase diagram with an increasing doping level.In addition to the charge density wave states at lower doping levels,we found an emergent Fermi-liquid-like phase by melting the holon Wigner crystal at δ≈0.15,which is characterized by the suppression of charge density oscillation and power-law decay of various correlation functions.For a wider L_(y)=4 cylinder,the bond-dimension extrapolated correlation functions also support such a Fermi-liquid-like state,suggesting its stability with increasing system size.In a narrow doping range near δ=1/3 for the L_(y)=3 cylinder,we find a state with an exponential decay of the single-particle correlation,but the other correlation functions preserve the features in the Fermi-liquid-like phase,which may be a precursor of a superconducting state.Nevertheless,this peculiar state nearδ=1/3 disappears for the L_(y)=4 cylinder,implying a possible lattice-size dependence.Our results reveal quantum melting from a holon Wigner crystal to a Fermi-liquid-like state with increasing hole density and suggest a doping regime to explore superconductivity in future studies.
基金National Key Research and Development Program of China (No.2021YFB3700105)。
文摘The thermotropic liquid crystal polyester(TLCP)fiber is an increasingly important strategic high-performance fiber.In this paper,the TLCP was prepared by two-step melt polymerization using 4-hydroxybenzoic acid(HBA)and 6-hydroxy-2-naphthoic acid(HNA)as comonomers at a molar ratio of 7∶3.The structure of TLCP was confirmed by the Fourier transform infrared(FTIR)spectrometer and nuclear magnetic resonance(NMR)spectrometer.The thermal and rheological properties of TLCP before and after heat treatment were analyzed systematically by the differential scanning calorimeter(DSC),dynamic mechanical analyzer(DMA)and high-temperature rotational rheometer.The results revealed that the melting temperature,glass transition temperature and melt viscosity of the TLCP increased significantly after heat treatment.It indicates that the crystallization of the TLCP is perfect,and solid-phase condensation occurs during heat treatment,which increases its molecular mass.In conclusion,heat treatment at a temperature below but close to the melting temperature can effectively regulate the structure and properties of the TLCP,and the results of this study can provide a reference for the high strengthening of TLCP fibers.
基金supports from the National Key Research and Development Program of China(2023YFB2806803)the National Natural Science Foundation of China(62075127).
文摘Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However,chromatic aberration remains a serious longstanding problem for diffractive optics,hindering their broader adoption.To overcome the chromatic aberrations for red,green and blue(RGB)light sources,in this paper,we propose a counterintuitive multi-twist structure to achieve narrowband PBOEs without crosstalk,which plays a vital role to eliminate the chromatic aberration.The performance of our designed and fabricated narrowband Pacharatnam-Berry lenses(PBLs)aligns well with our simulation results.Furthermore,in a feasibility demonstration experiment using a laser projector,our proposed PBL system indeed exhibits a diminished chromatic aberration as compared to a broadband PBL.Additionally,polarization raytracing is implemented to demonstrate the versatility of the multi-twist structure for designing any RGB wavelengths with high contrast ratios.This analysis explores the feasibility of using RGB laser lines and quantum dot light-emitting diodes.Overall,our approach enables high optical efficiency,low fabrication complexity,and high degree of design freedom to accommodate any liquid crystal material and RGB light sources,holding immense potential for widespread applications of achromatic PBOEs.
文摘The liquid crystalline polymers with photosensitive groups can self-assemble.When the polymer film is exposed to linearly polarized ultraviolet(LPUV),it can react a polarization-axis selective photoreaction.A small optical anisotropy presented from an axis-selective photoreaction of the photosensitive groups.When annealing in the liquid crystal temperature,a large optical anisotropic change of the polymer film was appeared.In the paper,the photoreaction property of polymer containing coumarin photosensitive group was measured by an ultraviolet spectrum method.The photochemical reaction property corresponding to the different exposure temperature and energy was investigated.The orientation performance at different annealing conditions was also conducted.The results indicated that when the exposure temperature is 70℃and 130℃,ΔA achieve the maximum and the corresponding exposure energy is the minimum.The corresponding DP is around 45%,when the exposure energy is 320 mJ/cm^(2) and 384 mJ/cm^(2),and the annealing temperature is 160℃,the correspondingΔA and S reach the maximum,ΔA=0.22 and S=0.048,respectively.
文摘This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized via the esterification of phytosterol and oleic acid,whose structure was characterized using Fourier-transform infrared spectroscopy(FTIR)and mass spectrometry(MS).Its liquid crystalline behavior was confirmed via the polarized optical microscopy(POM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),wide-angle X-ray scattering(WAXS),and small-angle X-ray scattering(SAXS).UV absorption tests were conducted to assess the UV-blocking performance of the oleic acid sterol ester liquid crystals.To improve the stability of its liquid crystalline structure,the oleic acid sterol ester was encapsulated into microcapsules through the emulsion polymerization.SPF measurements were performed on the sunscreen formulations containing liquid crystal microcapsules.The oleic acid sterol ester displayed cholesteric liquid crystalline behavior and strong UVA absorption,which indicates its suitability as a natural UV absorber.Microencapsulation further enhanced its stability and UV-blocking properties.SPF testing showed that the formulations with microcapsules achieved an SPF value of 7.01,which surpasses the nano titanium dioxide(SPF=6.23)and significantly outperform the unencapsulated liquid crystal formulations(SPF=2.65).This study highlights the potential of microencapsulated oleic acid sterol ester as a novel UV absorber in the sunscreen formulations,offers the enhanced stability and effective UV protection,and showcases its application potential in the innovative cosmetic products.
文摘The memory behavior in liquid crystals(LCs)that is characterized by low cost,large area,high speed,and high-density memory has evolved from a mere scientific curiosity to a technology that is being applied in a variety of commodities.In this study,we utilized molybdenum disulfide(MoS_(2))nanoflakes as the vip in a homotropic LCs host to modulate the overall memory effect of the hybrid.It was found that the MoS₂nanoflakes within the LCs host formed agglomerates,which in turn resulted in an accelerated response of the hybrids to the external electric field.However,this process also resulted in a slight decrease in the threshold voltage.Additionally,it was observed that MoS₂nanoflakes in a LCs host tend to align homeotropically under an external electric field,thereby accelerating the refreshment of the memory behavior.The incorporation of a mass fraction of 0.1%2μm MoS₂nanoflakes into the LCs host was found to significantly reduce the refreshing memory behavior in the hybrid to 94.0 s under an external voltage of 5 V.These findings illustrate the efficacy of regulating the rate of memory behavior for a variety of potential applications.
基金supported by the National Key Research and Development Program of China(No.2023YFB3812500)the National Natural Science Foundation of China(No.52105003)+1 种基金Beijing Municipal Natural Science Foundation(No.2222058)Fundamental Research Funds for the Central Universities(No.YWF-22-K-101)。
文摘Soft robots have shown great advantages with simple structure,high degree of freedom,continuous deformation,and benign human-machine interaction.In the past decades,a variety of soft robots,including crawling,jumping,swimming,and climbing robots,have been developed inspired by living creatures.However,most of the reported bionic soft robots have only a single mode of motion,which limits their practical application.Herein,we report a fully 3D printed crawling and flipping soft robot using liquid metal incorporated liquid crystal elastomer(LM-LCE)composite as the actuator.With the application of voltage,liquid metal works as the conductive Joule heating material to induce the contraction of the LCE layer.The bending angle of the LM-LCE composite actuator highly depends on the applied voltage.We further demonstrate that the soft robot can exhibit distinct moving behaviors,such as crawling or flipping,by applying different voltages.The fully 3D printed LM-LCE composite structure provides a strategy for the fast construction of soft robots with diverse motion modes.
基金financial support from the Natural Sciences and Engineering Research Council of Canada(NSERC),le Fonds de recherche du Québec:Nature et technologies(FRQNT),and The Centre québécois sur les matériaux fonctionnels.
文摘Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and actuation behaviors have been obtained in either hydrogels or LCEs,they typically undergo reversible shape change only once(e.g.,one expansion plus one contraction)during one heating/cooling cycle.Herein,we report a study of a novel liquid crystalline hydrogel(LCH)and the achievement of dual actuation in a single heating/cooling cycle by integrating the characteristics of thermoresponsive hydrogel and LCE.The dual actuation behavior arises from the reversible volume phase transition of poly(N-isopropylacrylamide)(PNIPAM)and the reversible order-disorder phase transition of LC mesogens in the LCH.Due to a temperature window separating the two transitions belonging to PNIPAM and LCE,LCH actuator can sequentially execute their respective actuation,thus deforming reversibly twice,during a heating/cooling cycle.The relative actuation degree of the two mechanisms is influenced by the mass ratio of PNIPAM to LCE in the LCH.Moreover,the initial shape of a bilayer actuator made with an active LCH layer and a passive polymer layer can be altered through hydration or dehydration of PNIPAM,which further modifies the dual actuation induced deformation.This work provides an example that shows the interest of developing LCH actuators.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFA1203700)the National Natural Science Foundation of China(Grant Nos.62405129 and 62035008)+4 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20241197)the China Postdoctoral Science Foundation(Grant No.2024T170396)the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20240678)the Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2024ZB684)the Fundamental Research Funds for the Central Universities(Grant No.021314380244).
文摘Polarization,the vector nature of electromagnetic waves,plays a vital role in optics.Polarization is characterized by the amplitude contrast and phase difference between two orthogonal polarization states.The present polarimeters usually perform a series of intensity measurements to carry out the polarization detection,making the process bulky and time-consuming.Thereby,compact and broadband-available polarimetry within a single snapshot is urgently demanded.We propose an all-liquid-crystal polarimeter for broadband polarization detection.It is cascaded by a q-plate and a polarization grating.The former is electrically tuned to meet the half-wave condition,whereas the latter is driven to deviate from this condition.After a polarized light passes through this device followed by a polarizer,its amplitude contrast and phase difference between orthogonal spins are read directly from the diffraction pattern.The intensity contrast between±1st orders depicts the amplitude contrast,whereas the rotating angle of the dark split reveals the phase difference.The Stokes parameters can be calculated accordingly.The polarimeter works in a broad spectral range of 470 to 1100 nm.Through presetting a q-plate array,polarization imaging is demonstrated.It supplies an all-liquid-crystal and full-visible-band tunable Stokes polarimeter that significantly promotes advances in polarization optics.
基金supported by the University Natural Science Research Project of Anhui Province(Grant Nos.2022AH040042 and 2022AH020029)the National Natural Science Foundation of China(Grant No.12172001)+1 种基金Anhui Provincial Natural Science Foundation(Grant No.2208085Y01)the Housing and Urban-Rural Development Science and Technology Project of Anhui Province(Grant No.2022-YF069).
文摘Recent experiments have found that a liquid crystal elastomer(LCE)rod supported in the middle can rotate continuously under horizontal illumination due to the combined impacts of gravity and light-fueled lateral bend-ing deformation.Similar to traditional gravity-driven systems,it is constrained by the direction of gravity and cannot be applied in microgravity environments.This study introduces a lateral constraint to a liquid crystal elastomer rod system,enabling self-rotation under lighting from any direction,including horizontal and vertical illumination.Through theoretical modeling,the results indicate that the system can steadily rotate under the combined impacts of lateral forces and vertical illumination.Factors like thermal energy flux,thermal conduc-tivity coefficient,the LCE rod length,contraction coefficient,and friction coefficient affect the angular velocity of the self-rotation.The numerical computations align closely with the experimental data.Our proposed steadily self-rotating system features a simple structure with constant self-rotation.It operates independently of gravity direction,making it an excellent choice for special environments,such as the microgravity conditions on the Moon.The lateral constraint strategy presented in this study offers a general approach to expanding the applica-tions of gravity-driven self-sustained motion,with promising potential,especially in microgravity settings,where its versatility under varying lighting conditions could yield valuable insights.
基金Supported by National Natural Science Foundation of China(11871305,11901346).
文摘In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy estimation,we obtain that the trivial solution u=Q=0 is the unique solution.Our theorems correspond to improvements of some recent results and contain some known results as particular cases.
基金supported by the National Natural Science Foundation of China(No.12172001)the University Natural Science Research Project of Anhui Province of China(No.2022AH020029)+1 种基金the Anhui Provincial Natural Science Foundation(Nos.2208085Y01 and 2008085QA23)the Housing and Urban-Rural Development Science and Technology Project of Anhui Province of China(No.2023-YF129)。
文摘Conventional liquid crystal elastomer(LCE)-based robots are limited by the need for complex controllers and bulky power supplies,restricting their use in microrobots and soft robots.This paper introduces a novel light-powered dicycle that uses an LCE rod,enabling self-rolling by harvesting energy from the environment.The LCE rod serves as the driving force,with energy being supplied by a line light source.Employing a dynamic LCE model,we calculate the transverse curvature of the LCE rod after deformation,as well as the driving moment generated by the shift in a rod’s center of gravity,which allows the dicycle to roll on its own.Through extensive numerical simulations,we identify the correlations between the angular velocity of the dicycle and the key system parameters,specifically the light intensity,LCE rod length,light penetration depth,overall mass of the dicycle,rolling friction coefficient,and wheel radius.Further,the experimental verification is the same as the theoretical result.This proposed light-powered self-rolling dicycle comes with the benefits of the simple structure,the convenient control,the stationary light source,and the small luminous area of the light source.It not only demonstrates self-sustaining oscillations based on active materials,but also highlights the great potential of light-responsive LCE rods in applications such as robotics,aerospace,healthcare,and automation.
文摘Using the back skin of the mice as the test object,UPLC was used to determine the retention rate of Glabridin(GLA)in the skin and subcutaneous fat pf mice with different dosage forms and different administration times,and to investigate the transdermal absorption effect of liquid crystal cream.The experimental results showed that the 0.5,1,2,4,6 and 8h skin retention rates of GLA in the liquid crystal cream group were 1.67,0.79,1.73,1.47,1.17 and 1.15 times higher than those of the ordinary cream group under the same dosage of administration,respectively.The 0.5,1,2,4,6 and 8 h fat retention rates of GLA in the normal cream group were 0.86,1.87,1.37,1.20,1.35 and 1.19 times higher than those in the liquid crystal group,respectively.Liquid crystal cream can significantly improve the skin retention of GLA,with certain slow and controlled release,and possesses certain skin targeting properties.
基金supported by the National Natural Science Foundation of China(Grant Nos.12322207,12202120 and T2293720/T2293722)the Shenzhen Science and Technology Program,China(Grant No.JCYJ20220531095210022)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.HIT.OCEF.2022037)financial support by the National Key Research and Development Program of China(Grant No.2023YFB3812500)。
文摘Liquid crystal elastomers(LCEs)are advanced materials characterized by their rubber-like hyperelasticity and liquid crystal phase transitions,offering exceptional mechanical properties.The development of smart mechanical metamaterials(SMMs)from LCEs expands the potential for controlling mechanical responses and achieving nonlinear behaviors not possible with traditional metamaterials.However,the challenge lies in managing the interplay between nonlinear material responses and structural complexity,making the inverse design of LCE-based SMMs exceptionally demanding.In this paper,we introduce a design framework for LCE smart mechanical metamaterials that leverages neural networks and evolution strategies(ES)to optimize designs with nonlinear mechanical responses.Our approach involves constructing a flexible,unit-cell-based metamaterial model that integrates the soft elastic behavior and thermo-mechanical coupling of LCEs.The combination of microscopic liquid crystal molecule rotation and macroscopic block rotation enables highly tunable and nonlinear mechanical behaviors,of which the precise inverse design of stress-stretch responses is obtained via neural networks combined with ES.In addition,stimuli responses in the liquid crystal elastomers enable real-time adaptability and achieve tailored stress plateaus that are not possible with traditional metamaterials.Our findings provide new pathways in the design and optimization of advanced materials in flexible electronic devices,intelligent actuators,and systems for energy absorption and dissipation.
基金supported by the National Natural Science Foundation of China(Grant Nos.12174285 and 12474315)support from the National Natural Science Foundation of China(Grant No.62375200)+2 种基金support from the National Natural Science Foundation of China(Grant No.12504372)the China Postdoctoral Science Foundation-Tianjin Joint Support Program(Grant No.2025T003TJ)support from the National Natural Science Foundation of China(Grant No.12404424)。
文摘Two-dimensional(2D)transition-metal dichalcogenide(TMD)monolayers based on become a promising platform to study photonics and optoelectronics.Electrically controlling the excitonic properties of TMD monolayers can be realized in different devices.In this work,we realize the strong coupling between the excitons of WS_(2)monolayers and a photonic cavity mode in a liquid crystal microcavity.The formed exciton polaritons can be electrically tuned by applying voltage to the microcavity.Our work offers a way to study exciton-polariton manipulation based on TMD monolayers by electrical methods at room temperature.
文摘Liquid crystal emulsifiers are widely used in skincare formulations due to their unique structural properties.In formulation development,components such as thickeners,oils,and co-emulsifiers significantly affect liquid crystal formation.Using polyglyceryl-10 stearate as an emulsifier,we investigated the effects of thickeners,oils,higher alcohols,and fatty acids on liquid crystal structure through controlled single-factor experiments.The results showed that xanthan gum(thickener),pentaerythrityl tetraisostearate(oil),and cetearyl alcohol(higher alcohol)produced optimal liquid crystal formation,with fatty acids providing additional benefits.Homogenization speed had the most pronounced impact-both excessively high and low speeds negatively affected the liquid crystal structure.
基金financially supported by the National Natural Science Foundation of China(Nos.52275290 and 51905222)the Research Project of the State Key Laboratory of Mechanical System and Oscillation(No.MSV202419)+2 种基金Major Program of the National Natural Science Foundation of China for Basic Theory and Key Technology of Tri-Co Robots(No.92248301)Opening Project of the Key Laboratory of Bionic Engineering(Ministry of Education),Jilin University(No.KF2023006)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX23_2091)。
文摘This work proposes a bioinspired hierarchical actuation strategy based on liquid crystal elastomers(LCEs),inspired by the helical topological dynamic adaptation mechanism of plant tendrils,to overcome the bottleneck of precise anisotropic control in LCEs.Mechanically pre-programmed hierarchical LCE structures responsive to near-infrared(NIR)light were fabricated:the oriented constrained actuator achieves asymmetric contraction under NIR irradiation,enabling reversible switching between helix and planar morphologies with multi-terrain grasping capability;the biomimetic vine-like helical actuator,composed of Ag nanowire photothermal layers combined with helical LCE,utilizes temperaturegradient-induced phase transition wave propagation to achieve NIR-controlled climbing motion;the M?bius topology actuator realizes reversible deformation or self-locking states by tuning the twist angle(180°/360°);based on these,a bioinspired koala-like concentric soft robot was constructed,successfully demonstrating tree trunk climbing.This study reveals that artificial helical stretching significantly enhances the molecular chain orientation of LCEs(surpassing uniaxial stretching),reaching up to 1000%pre-strain,and the Ag NWs/LCE/PI(Polyimide)tri-layer structure achieves efficient photothermal-mechanical energy conversion via localized surface plasmon resonance(LSPR).This study provides a new paradigm for soft robotics material design and topological programming,demonstrating the potential for remote operation and adaptive grasping.
基金financially supported by the National Key Research and Development Program of China(No.2023YFB3812500)the National Natural Science Foundation of China(No.52105003)the Beijing Municipal Natural Science Foundation(No.2222058)。
文摘Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid crystal elastomer(LCE)pillar arrays are capable of exhibiting significant and reversible anisotropic deformation under cyclic heating and cooling,showing great potential in tunable adhesion,soft robots,and biomedical devices.However,scaling up LCE pillar manufacturing remains challenging,limiting its practical applications.In this work,a solventfree LCE resin is developed with unique features including simple operating procedure,short fabrication time,and tunable responsive temperature,enabling rapid and large-scale production of LCE pillar arrays.The LCE resin allows for the preparation of complex 3D shapes in addition to film or specimen.The fabrication time can be as short as 4 h,without the need to evaporate solvent.Moreover,the LCE resins can be adjusted with a variable phase transition temperature range from 49.4℃ to 97.7℃ by incorporating non-liquid crystal acrylate chains.The resulting active pillar array structure can undertake sequential actuation upon heating with the tunable actuation temperature.Finally,the application of these pillar arrays in multi-level information encryption is demonstrated.The LCE pillar structure introduced here offers a new strategy for constructing advanced active LCE structures with tunable responsive behavior.
