Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nu...Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa ＇Luosheng No.3＇ as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range （（20 ± 1）℃） and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer.展开更多
The microstructure changed markedly with increasing solution temperature, i.e eutectic γ' phases and coarse primary γ' phase are redissolved continuously into matrix, which was finished at 1250-1260℃, and m...The microstructure changed markedly with increasing solution temperature, i.e eutectic γ' phases and coarse primary γ' phase are redissolved continuously into matrix, which was finished at 1250-1260℃, and more and finer γ' phases are reprecipitated. The grain boundary morphology changed gradually to 'fine line' form. The dendritic segregation of elements decreased. With raising solution temperature the longitudinal stress-rupture life at high and intermediate temperature were enhanced, but the transversal stress-rupture life at intermediate temperature decreased obviously. The incipient melting temperature of DZ22 alloy was measured to be 1230-1240℃ and may be increased by homogenization at 1150℃. In this paper the principle of determining solution temperature of DS alloys was discussed. It was suggested that the solution temperature of alloy DZ22 selected at 1200-1210℃ is appropri- ate.展开更多
Near-infrared light(NIR)triggered transdermal drug delivery systems are of great interest due to their on-demand drug release,which enable to enhance drug treatment efficiency as well as reduce side effect.Herein,a NI...Near-infrared light(NIR)triggered transdermal drug delivery systems are of great interest due to their on-demand drug release,which enable to enhance drug treatment efficiency as well as reduce side effect.Herein,a NIR-triggered microneedle(MN)patch array has been fabricated through depositing the photothermal conversion agent and anti-diabetic drug-loaded polymer vesicles with upper critical solution temperature(UCST)into dissolvable polymer matrix.The UCST-type polymer has a clearing point temperature of 41℃ and the drug-loaded polymer vesicles present excellent NIR-triggered and temperature responsive drug release behavior in vitro due to the disassociation of polymer vesicles upon NIR irradiation.After applying MNs to diabetic rats,significant hypoglycemic effect is achieved upon interval NIR irradiation and the blood glucose concentration can decrease to normal state for several hours,which enables to achieve the goal of on-demand drug release.This work suggests that the NIR-triggered MN drug release device has a potential application in the treatment of diabetes,especially for those requiring an active drug release manner.展开更多
Objective To evaluate the effect of tumescent infiltration solution temperature on core body temperatureafter liposuction.Methods 15 healthy female subjects were randomly divided into 2 groups to receive tumescent inf...Objective To evaluate the effect of tumescent infiltration solution temperature on core body temperatureafter liposuction.Methods 15 healthy female subjects were randomly divided into 2 groups to receive tumescent infiltration展开更多
Extreme nutrient solution temperature significantly affects photosynthetic characteristics of hydroponic vegetables and gives rise to slow plant growth.In this study,a method was proposed to obtain the suitable nutrie...Extreme nutrient solution temperature significantly affects photosynthetic characteristics of hydroponic vegetables and gives rise to slow plant growth.In this study,a method was proposed to obtain the suitable nutrient solution temperature range of hydroponic crops.Nested experiments of net photosynthetic rates were designed.The experiments considered the impact of nutrient solution temperatures,air temperatures,photon flux densities,and CO_(2) concentrations.Then we established a prediction model of photosynthetic rate based on a regression support vector machine.The results have shown that the coefficient of determination between the measured values and the predicted values of photosynthetic rate is 0.982,and the root mean square error is 0.990μmol/m2·s.Taking the net photosynthetic rate prediction model as the objective function,the maximum photosynthetic rate could be found using multiple population genetic algorithms,and then the nutrient solution temperature response curve could be created.According to the U-chord curvature theory,the suitable nutrient solution temperature range was calculated.After optimization by the multi-population genetic algorithm,the coefficient of determination between measured values and optimized values of maximum photosynthetic rate was 0.989 and the mean square error was 0.003.An analysis of the calculation based on the theory of U-chord curvature indicated that the suitable nutrient solution temperature range to grow hydroponic lettuce is 20.04°C-26.32°C.The proposed method provides a solid foundation to accurately acquire the suitable nutrient solution temperature range for a crop grown in hydroponics.展开更多
The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by t...The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by turbidity measurement and electron microscopy, which are significantly restricted by low sensitivity and static observation. In contrary, the fluorescence technique has significant advantages in terms of high sensitivity, easy operation, and dynamic observation. However, the conventional fluorophores suffer from the drawbacks of aggregation-caused quenching(ACQ) after being encapsulated by UCST polymers, which are not suitable for direct visualization of the phase transition process. To tackle this challenge, we herein developed a series of UCST polymers based on polyacrylamides decorated with bile acid and aggregation-induced emission(AIE)-active tetraphenylethene(TPE) groups, which can be used for direct fluorescence monitoring of the phase transition process. Moreover, the AIE-active UCST polymers can serve as drug carriers, which can not only monitor the drug release process under thermal stimuli, but also verify the drug release by fluorescence recovery after thermal stimuli. It is expected that the AIE-active UCST polymers with self-monitoring ability are promising for biomedical applications.展开更多
Lower critical solution temperature(LCST)is the critical temperature below which the solution is miscible for all compositions and above which the solution becomes a suspension.The study of LCST properties has become ...Lower critical solution temperature(LCST)is the critical temperature below which the solution is miscible for all compositions and above which the solution becomes a suspension.The study of LCST properties has become a central research topic due to its profound impact on the applications of stimuli-responsive materials.Inspired by the marriage between materials science and supramolecular chemistry,the introduction of supramolecular pairs and interactions into polymeric LCST systems is increasingly practiced.Especially,supramolecular interactions provide precise control over LCST behavior in both water and organic solvents.Furthermore,supramolecular interactions not only control or adjust LCST behavior(supramolecular interaction controlled LCST),but also induce LCST phase behavior in species lack of thermo-sensitive properties(supramolecular interaction induced LCST).In this review,we summarize the applications of supramolecular interactions in LCST systems.By examining the relationship between supramolecular interactions and LCST changes,we further discuss the differences between supramolecular interaction controlled LCST and supramolecular interaction induced LCST.We hope this review will give our readers a snapshot on how the supramolecular interactions influence the LCST behavior in various systems,and benefit them with different applications.展开更多
Crystal Growth in space is a crystalline process with long Period microgravity conditions.So far,on earth there are some facilities,such as DroP Tube,Drop Tower,Ballon,Sounding Rochets and Aircraft etc.They provide th...Crystal Growth in space is a crystalline process with long Period microgravity conditions.So far,on earth there are some facilities,such as DroP Tube,Drop Tower,Ballon,Sounding Rochets and Aircraft etc.They provide the microgravity conditions with the range of period from seconds to minutes.展开更多
Circular double stranded DNA has different topological states which are defined by their linking numbers. Equilibrium distribution of linking numbers can be obtained by closing
Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protect...Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protection,such as temperature-responsive electrodes,and thermal-shutdown separators,these methods only provide irreversible protection.Recently,reversible temperature-sensitive electrolytes have emerged as promising alternatives,offering both thermo-reversibility and self-protective properties.However,further research is crucial to fully understand these thermal-shutdown electrolytes.In this study,we propose lower critical solution temperature(LCST)phase behavior poly(benzyl methacrylate)/imidazolium-based ionic liquid mixtures to prepare temperature-sensitive electrolytes that provide reversible thermal shutdown protection of batteries.This electrolyte features an appropriate protection temperature(~105℃)and responds quickly within a 1 min at 105℃,causing cells to hardly discharge as the voltage suddenly drops to 3.38 V,and providing efficient thermal shutdown protection within 30 min.Upon cooling back to room temperature,the battery regains its original performance.Additionally,the electrolyte exhibits excellent cycling stability with the capacity retention of the battery is 91.6%after 500 cycles.This work provides a viable solution for preventing batteries from thermal runaway triggered by overheating.展开更多
Evolution laws of microstructures,mechanical properties,and fractographs after different solution temperatures were investigated through various analysis methods.With the increasing solution temperatures,contents of t...Evolution laws of microstructures,mechanical properties,and fractographs after different solution temperatures were investigated through various analysis methods.With the increasing solution temperatures,contents of the primaryαphase decreased,and contents of transformedβstructures increased.Lamellarαgrains dominated the characteristics of transformedβstructures,and widths of secondaryαlamellas increased monotonously.For as-forged alloy,large silicides with equiaxed and rod-like morphologies,and nano-scale silicides were found.Silicides with large sizes might be(Ti,Zr,Nb)_(5)Si_(3) and(Ti,Zr,Nb)_(6)Si_(3).Rod-like silicides with small sizes precipitated in retainedβphase,exhibiting near 45°angles withα/βboundaries.Retainedβphases in as-heat treated alloys were incontinuous.980STA exhibited an excellent combination of room temperature(RT)and 650°C mechanical properties.Characteristics of fracture surfaces largely depended on the evolutions of microstructures.Meanwhile,silicides promoted the formation of mico-voids.展开更多
In this study, acrylic acid （AA） and 4-azidoaniline were used to modify poly （N-isopropylacrylamide） （NIPAAm） in order to fabricate temperature-responsive surface for corneal epithelia cell adhesion and detachme...In this study, acrylic acid （AA） and 4-azidoaniline were used to modify poly （N-isopropylacrylamide） （NIPAAm） in order to fabricate temperature-responsive surface for corneal epithelia cell adhesion and detachment. First, NIPAAm was copolymerized with acrylic acid. Then, the copolymer was coupled with azidoaniline to synthesize AzPhPIA, derivative of p（NIPAAm-co-AA）, which possesses both thermo- and photo-sensitivities. Second, the synthesized copolymer was characterized by high performance liquid chromatography （HPLC）, Fourier transform infrared （FTIR） and a CHN analyzer. The thermo-sensitivity was characterized by temperature reducing experiment, contact angle measurement and low critical solution temperature （LCST） testing. Third, the derivatized copolymer was immobilized by photolithography on a polystyrene plate, and then the surface characterization of AzPhPIA-coated polystyrene plate （PSt） was measured by electron spectroscopy for chemical analysis （ESCA）. The thermo-sensitivity and cytocompatibility of the AzPhPIA-coated PSt were investigated by corneal epithelial cells culture. The results revealed that the AzPhPIA-coated PSt exhibited good cytocompatibility and cell detachability when temperature decreased.展开更多
Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temp...Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature（LCST） is often sharp, which allows for a wide range of smart material applications.At the LCST, oligo（ethylene glycol）-substituted polyisocyanides（PICs） form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol（EG） tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.展开更多
The secondary phases of the steels have significant effects on the microstructure and mechanical properties, making controlling these secondary phases important. The control of MnS inclusions and A1N precipitates in a...The secondary phases of the steels have significant effects on the microstructure and mechanical properties, making controlling these secondary phases important. The control of MnS inclusions and A1N precipitates in a N-alloyed high-Mn twin-induced plastic cryogenic steel via solution treatment was investigated with several different techniques including microstructural characterization, 298 K tensile testing, and 77 K impact testing. The solutionizing temperature （ST） increased from 1323 to 1573 K, where the elongated MnS inclusions and large-sized AlN precipitates became spheroidized and dissolved. The aspect ratio of the MnS inclusions decreased as the ST increased and the number density increased. The impact toughness of the steels showed anisotropy and low impact energy values, due to the elongated MnS inclusions and large-sized AIN precipitates. The anisotropy was eliminated by spheroidizing the MnS inclusions. The impact energy was improved by dissolving the large-sized AlN precipitates during the solution treatment. The austenite grain size increased when the dissolution of the AlN precipitate increased, but the effect of the grain size on the yield strength, toughness, and the strength--ductility balance was weak.展开更多
The synthesis of active electrode materials at room temperature is one of the effective strategies to reduce the fabrication cost of sodium ion batteries(SIBs).Herein,a layered material(Na_(2)[(VO)_(2)(HPO_(4))_(2)C_(...The synthesis of active electrode materials at room temperature is one of the effective strategies to reduce the fabrication cost of sodium ion batteries(SIBs).Herein,a layered material(Na_(2)[(VO)_(2)(HPO_(4))_(2)C_(2)O_(4)]·2H_(2)O,abbreviated as NVPC followingly)with open-framework structures has been successfully prepared at room temperature under ambient conditions and is evaluated as a cathode for SIBs.It is revealed that NVPC cathode can deliver a maximum reversible capacity of ca.70 mAh/g at 10 mA/g,and exhibit superior rate capability and cycling performance:at 50 mA/g,maximum reversible capacity ca.50 m Ah/g with capacity retention of 88.4%over 250 cycles corresponds to only 0.046%capacity decay per cycle;at 100 mA/g,a maximum reversible capacity of 35 mAh/g with capacity retention of60.9%over 500 cycles.This study demonstrates a practical example of a low-cost synthesis of the cathode materials for SIBs.At the same time,the systematic electrochemical research results also show promising prospects for long lifespan low-cost SIBs.展开更多
A kinetic model based on the classical nucleation and growth theory has been proposed to predict the precipitation behavior of complex precipitate. The method for calculating absolute solution temperature, which is an...A kinetic model based on the classical nucleation and growth theory has been proposed to predict the precipitation behavior of complex precipitate. The method for calculating absolute solution temperature, which is an important guidance for determining solution treatment temperature, is also proposed based on thermodynamic model. In the model, nucleation of the second phase is assumed to be controlled by the effective diffusion, which involves the bulk diffusion and dislocation pipe diffusion, and growth is controlled by the bulk diffusion of forming elements. The interfacial energy of complex precipitate is calculated by the linear interpolation method, and the effects of alloying elements on precipitation behavior are manifested using weighted means of their diffusivities and concentration. The predictions were compared with the experimental measurements, and a good agreement was obtained.展开更多
Phase transition behavior and influence of ions on the thermo-sensitive polyamide with polyethylene glycol as the main chain were studied in detail. By measuring the light transmission rates of polymer solutions, the ...Phase transition behavior and influence of ions on the thermo-sensitive polyamide with polyethylene glycol as the main chain were studied in detail. By measuring the light transmission rates of polymer solutions, the change of its lower critical solution temperature （LCST） in the salt solution was investigated. It was found that a reversible phase transition of the polyamide occurred at the LCST and finished in a narrow temperature range. The LCST was associated with species of ions in salt solution. Anions had a great impact on the phase transition performance of the thermo-sensitive polyamide, while the cations had a slight influence on the phase transition. Different anions had different coagulation ability to ‘salt-out＇ the polyamide. The order was： CO2-3〉SiO2-3〉HPO2-4〉OH-〉Cl-〉HCO3-〉HSOa-〉NO2-〉NO3-.展开更多
A hybrid system containing a pillar[5]arene unit and ten crown ether moieties was developed.The LCST behavior and thermo-responsive ness were successfully introduced into this pillar[5]arene-crown ether system.Both ho...A hybrid system containing a pillar[5]arene unit and ten crown ether moieties was developed.The LCST behavior and thermo-responsive ness were successfully introduced into this pillar[5]arene-crown ether system.Both host-vip interactions and salting-out effect displayed great effects in realizing the supramolecular control over LCST properties and the rmo-re sponsiveness.Compa red with the individual macrocycles,this hybrid macrocycle system dramatically amplified the supramolecular control effect over LCST behavior.展开更多
The thermosensitive poly （ N-isopropylacrylamide ） （PNIPAAm） and poly （N-isopropylacrylamide-co-acrylamide） [ poly （NIPAAm-co-AAm） ] hydrogels with different acrylamide molar percentage are prepared by radiati...The thermosensitive poly （ N-isopropylacrylamide ） （PNIPAAm） and poly （N-isopropylacrylamide-co-acrylamide） [ poly （NIPAAm-co-AAm） ] hydrogels with different acrylamide molar percentage are prepared by radiation polymerization using Co^60 γ-ray. Their swelling equilibrium data in the media of deionized water, NaCl aqueous solutions and different pH buffer solutions are determined. It appears that lower critical solution temperature （LCST） of the hydrogels will drop with the increase of ionic strength and increase with the rising of acrylamide content, A semi-empirical formula is set up with the experimental results. Moreover, it also indicates that this copolymer is pH-sensitive, which is similar to the homopolymer of PNIPAAm.展开更多
CONSPECTUS:Thermoresponsive hydrogels possess an inherent capacity for autonomous adjustment of their properties in response to temperature variations,eliminating the requirement for external power sources and renderi...CONSPECTUS:Thermoresponsive hydrogels possess an inherent capacity for autonomous adjustment of their properties in response to temperature variations,eliminating the requirement for external power sources and rendering them suitable for diverse environmental applications.Our discourse commences by establishing a foundational comprehension of the two principal categories governing thermal transitions in thermoresponsive hydrogels,namely,the Lower Critical Solution Temperature(LCST)and the Upper Critical Solution Temperature(UCST).展开更多
基金Supported by Science and Technology Innovative Leading Fund of Ningxia Academy of Agriculture and Forestry Sciences(NKYZ-16-1101)~~
文摘Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa ＇Luosheng No.3＇ as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range （（20 ± 1）℃） and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer.
文摘The microstructure changed markedly with increasing solution temperature, i.e eutectic γ' phases and coarse primary γ' phase are redissolved continuously into matrix, which was finished at 1250-1260℃, and more and finer γ' phases are reprecipitated. The grain boundary morphology changed gradually to 'fine line' form. The dendritic segregation of elements decreased. With raising solution temperature the longitudinal stress-rupture life at high and intermediate temperature were enhanced, but the transversal stress-rupture life at intermediate temperature decreased obviously. The incipient melting temperature of DZ22 alloy was measured to be 1230-1240℃ and may be increased by homogenization at 1150℃. In this paper the principle of determining solution temperature of DS alloys was discussed. It was suggested that the solution temperature of alloy DZ22 selected at 1200-1210℃ is appropri- ate.
基金financially supported by the Natural Science Foundation of Zhejiang Province(No.LY20E030005)the Opening Project of Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices(No.PMND201905)。
文摘Near-infrared light(NIR)triggered transdermal drug delivery systems are of great interest due to their on-demand drug release,which enable to enhance drug treatment efficiency as well as reduce side effect.Herein,a NIR-triggered microneedle(MN)patch array has been fabricated through depositing the photothermal conversion agent and anti-diabetic drug-loaded polymer vesicles with upper critical solution temperature(UCST)into dissolvable polymer matrix.The UCST-type polymer has a clearing point temperature of 41℃ and the drug-loaded polymer vesicles present excellent NIR-triggered and temperature responsive drug release behavior in vitro due to the disassociation of polymer vesicles upon NIR irradiation.After applying MNs to diabetic rats,significant hypoglycemic effect is achieved upon interval NIR irradiation and the blood glucose concentration can decrease to normal state for several hours,which enables to achieve the goal of on-demand drug release.This work suggests that the NIR-triggered MN drug release device has a potential application in the treatment of diabetes,especially for those requiring an active drug release manner.
文摘Objective To evaluate the effect of tumescent infiltration solution temperature on core body temperatureafter liposuction.Methods 15 healthy female subjects were randomly divided into 2 groups to receive tumescent infiltration
基金supported by the National Key Research and Development Program of China(Grant No.2020YFD1100602)the Shaanxi Key Research and Development Program(Grant No.2023-ZDLNY-66)the Shaanxi Provincial Science and Technology Program(Grant No.Z2024-ZYFS-0043).
文摘Extreme nutrient solution temperature significantly affects photosynthetic characteristics of hydroponic vegetables and gives rise to slow plant growth.In this study,a method was proposed to obtain the suitable nutrient solution temperature range of hydroponic crops.Nested experiments of net photosynthetic rates were designed.The experiments considered the impact of nutrient solution temperatures,air temperatures,photon flux densities,and CO_(2) concentrations.Then we established a prediction model of photosynthetic rate based on a regression support vector machine.The results have shown that the coefficient of determination between the measured values and the predicted values of photosynthetic rate is 0.982,and the root mean square error is 0.990μmol/m2·s.Taking the net photosynthetic rate prediction model as the objective function,the maximum photosynthetic rate could be found using multiple population genetic algorithms,and then the nutrient solution temperature response curve could be created.According to the U-chord curvature theory,the suitable nutrient solution temperature range was calculated.After optimization by the multi-population genetic algorithm,the coefficient of determination between measured values and optimized values of maximum photosynthetic rate was 0.989 and the mean square error was 0.003.An analysis of the calculation based on the theory of U-chord curvature indicated that the suitable nutrient solution temperature range to grow hydroponic lettuce is 20.04°C-26.32°C.The proposed method provides a solid foundation to accurately acquire the suitable nutrient solution temperature range for a crop grown in hydroponics.
基金supported by the National Natural Science Foundation of China(21704026,21788102,51620105009,21877040,U1801252,21602063,22075087)the Natural Science Foundation of Guangdong Province,China(2019A1515011129)+4 种基金the Science and Technology Program of Guangzhou(201804020060,202007020002,201704030069,202002030229)Pearl River S&T Nova Program of Guangzhou(201806010152)Fundamental Research Funds for the Central Universities(2018JQ01)Foundation for Xinghua Scholar of South China University of TechnologyNational Key R&D Program of China(2017YFC1103400,2017YFC1105004,2018YFC0311103)。
文摘The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by turbidity measurement and electron microscopy, which are significantly restricted by low sensitivity and static observation. In contrary, the fluorescence technique has significant advantages in terms of high sensitivity, easy operation, and dynamic observation. However, the conventional fluorophores suffer from the drawbacks of aggregation-caused quenching(ACQ) after being encapsulated by UCST polymers, which are not suitable for direct visualization of the phase transition process. To tackle this challenge, we herein developed a series of UCST polymers based on polyacrylamides decorated with bile acid and aggregation-induced emission(AIE)-active tetraphenylethene(TPE) groups, which can be used for direct fluorescence monitoring of the phase transition process. Moreover, the AIE-active UCST polymers can serve as drug carriers, which can not only monitor the drug release process under thermal stimuli, but also verify the drug release by fluorescence recovery after thermal stimuli. It is expected that the AIE-active UCST polymers with self-monitoring ability are promising for biomedical applications.
基金National Natural Science Foundation of China,Grant/Award Number:21801203HuxiangYoung Talent Program fromHunan Province,Grant/Award Number:2018RS3036。
文摘Lower critical solution temperature(LCST)is the critical temperature below which the solution is miscible for all compositions and above which the solution becomes a suspension.The study of LCST properties has become a central research topic due to its profound impact on the applications of stimuli-responsive materials.Inspired by the marriage between materials science and supramolecular chemistry,the introduction of supramolecular pairs and interactions into polymeric LCST systems is increasingly practiced.Especially,supramolecular interactions provide precise control over LCST behavior in both water and organic solvents.Furthermore,supramolecular interactions not only control or adjust LCST behavior(supramolecular interaction controlled LCST),but also induce LCST phase behavior in species lack of thermo-sensitive properties(supramolecular interaction induced LCST).In this review,we summarize the applications of supramolecular interactions in LCST systems.By examining the relationship between supramolecular interactions and LCST changes,we further discuss the differences between supramolecular interaction controlled LCST and supramolecular interaction induced LCST.We hope this review will give our readers a snapshot on how the supramolecular interactions influence the LCST behavior in various systems,and benefit them with different applications.
文摘Crystal Growth in space is a crystalline process with long Period microgravity conditions.So far,on earth there are some facilities,such as DroP Tube,Drop Tower,Ballon,Sounding Rochets and Aircraft etc.They provide the microgravity conditions with the range of period from seconds to minutes.
基金supported by the Young Investigator Award received by Yan in 2006the Foundation for the Visiting PhD Candidate of the Chinese Academy of Science received by Liu in 2006
文摘Circular double stranded DNA has different topological states which are defined by their linking numbers. Equilibrium distribution of linking numbers can be obtained by closing
基金funded by the National Natural Science Foundation of China(no.22075155)the Zhejiang Provincial Natural Science Foundation of China(No.LY24B030002)+2 种基金Ningbo Natural Science Foundation(2023J089)the China Scholarship Council(CSC)the Ningbo Science and Technology Bureau(2024QL036).
文摘Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protection,such as temperature-responsive electrodes,and thermal-shutdown separators,these methods only provide irreversible protection.Recently,reversible temperature-sensitive electrolytes have emerged as promising alternatives,offering both thermo-reversibility and self-protective properties.However,further research is crucial to fully understand these thermal-shutdown electrolytes.In this study,we propose lower critical solution temperature(LCST)phase behavior poly(benzyl methacrylate)/imidazolium-based ionic liquid mixtures to prepare temperature-sensitive electrolytes that provide reversible thermal shutdown protection of batteries.This electrolyte features an appropriate protection temperature(~105℃)and responds quickly within a 1 min at 105℃,causing cells to hardly discharge as the voltage suddenly drops to 3.38 V,and providing efficient thermal shutdown protection within 30 min.Upon cooling back to room temperature,the battery regains its original performance.Additionally,the electrolyte exhibits excellent cycling stability with the capacity retention of the battery is 91.6%after 500 cycles.This work provides a viable solution for preventing batteries from thermal runaway triggered by overheating.
基金The authors would like to gratefully acknowledge the support of Industrial Strengthen Foundation Project of Ministry of Industry and Information Technology,PRC(TC150B5C0-02).
文摘Evolution laws of microstructures,mechanical properties,and fractographs after different solution temperatures were investigated through various analysis methods.With the increasing solution temperatures,contents of the primaryαphase decreased,and contents of transformedβstructures increased.Lamellarαgrains dominated the characteristics of transformedβstructures,and widths of secondaryαlamellas increased monotonously.For as-forged alloy,large silicides with equiaxed and rod-like morphologies,and nano-scale silicides were found.Silicides with large sizes might be(Ti,Zr,Nb)_(5)Si_(3) and(Ti,Zr,Nb)_(6)Si_(3).Rod-like silicides with small sizes precipitated in retainedβphase,exhibiting near 45°angles withα/βboundaries.Retainedβphases in as-heat treated alloys were incontinuous.980STA exhibited an excellent combination of room temperature(RT)and 650°C mechanical properties.Characteristics of fracture surfaces largely depended on the evolutions of microstructures.Meanwhile,silicides promoted the formation of mico-voids.
基金supported by the National Natural Science Foundation of China (Nos.30970731 and 50832002)the Natural Science Foundation of Guangdong Province(No.9151063101000015)
文摘In this study, acrylic acid （AA） and 4-azidoaniline were used to modify poly （N-isopropylacrylamide） （NIPAAm） in order to fabricate temperature-responsive surface for corneal epithelia cell adhesion and detachment. First, NIPAAm was copolymerized with acrylic acid. Then, the copolymer was coupled with azidoaniline to synthesize AzPhPIA, derivative of p（NIPAAm-co-AA）, which possesses both thermo- and photo-sensitivities. Second, the synthesized copolymer was characterized by high performance liquid chromatography （HPLC）, Fourier transform infrared （FTIR） and a CHN analyzer. The thermo-sensitivity was characterized by temperature reducing experiment, contact angle measurement and low critical solution temperature （LCST） testing. Third, the derivatized copolymer was immobilized by photolithography on a polystyrene plate, and then the surface characterization of AzPhPIA-coated polystyrene plate （PSt） was measured by electron spectroscopy for chemical analysis （ESCA）. The thermo-sensitivity and cytocompatibility of the AzPhPIA-coated PSt were investigated by corneal epithelial cells culture. The results revealed that the AzPhPIA-coated PSt exhibited good cytocompatibility and cell detachability when temperature decreased.
基金the Netherlands Organisation for Scientific Research (NWO)for providing and supporting beam time at the DutchBelgium beamline(DUBBLE) for SAXS experiments(No. BM26-02773)financial support from NWO (VENI grant No. 680-47-437)+2 种基金the Euopean Union's 2020 ResearchInnovation Programme under Grant Agreement No. 642687project Biogel
文摘Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature（LCST） is often sharp, which allows for a wide range of smart material applications.At the LCST, oligo（ethylene glycol）-substituted polyisocyanides（PICs） form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol（EG） tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.
基金the financial support of the National Key Research and Development Program of China(Grant No.2017YFB0305101)
文摘The secondary phases of the steels have significant effects on the microstructure and mechanical properties, making controlling these secondary phases important. The control of MnS inclusions and A1N precipitates in a N-alloyed high-Mn twin-induced plastic cryogenic steel via solution treatment was investigated with several different techniques including microstructural characterization, 298 K tensile testing, and 77 K impact testing. The solutionizing temperature （ST） increased from 1323 to 1573 K, where the elongated MnS inclusions and large-sized AlN precipitates became spheroidized and dissolved. The aspect ratio of the MnS inclusions decreased as the ST increased and the number density increased. The impact toughness of the steels showed anisotropy and low impact energy values, due to the elongated MnS inclusions and large-sized AIN precipitates. The anisotropy was eliminated by spheroidizing the MnS inclusions. The impact energy was improved by dissolving the large-sized AlN precipitates during the solution treatment. The austenite grain size increased when the dissolution of the AlN precipitate increased, but the effect of the grain size on the yield strength, toughness, and the strength--ductility balance was weak.
基金financially supported by the National Natural Science Foundation of China(No.21805278)。
文摘The synthesis of active electrode materials at room temperature is one of the effective strategies to reduce the fabrication cost of sodium ion batteries(SIBs).Herein,a layered material(Na_(2)[(VO)_(2)(HPO_(4))_(2)C_(2)O_(4)]·2H_(2)O,abbreviated as NVPC followingly)with open-framework structures has been successfully prepared at room temperature under ambient conditions and is evaluated as a cathode for SIBs.It is revealed that NVPC cathode can deliver a maximum reversible capacity of ca.70 mAh/g at 10 mA/g,and exhibit superior rate capability and cycling performance:at 50 mA/g,maximum reversible capacity ca.50 m Ah/g with capacity retention of 88.4%over 250 cycles corresponds to only 0.046%capacity decay per cycle;at 100 mA/g,a maximum reversible capacity of 35 mAh/g with capacity retention of60.9%over 500 cycles.This study demonstrates a practical example of a low-cost synthesis of the cathode materials for SIBs.At the same time,the systematic electrochemical research results also show promising prospects for long lifespan low-cost SIBs.
基金This work was financially supported by the National Natural Science Foundation of China （51234002）.
文摘A kinetic model based on the classical nucleation and growth theory has been proposed to predict the precipitation behavior of complex precipitate. The method for calculating absolute solution temperature, which is an important guidance for determining solution treatment temperature, is also proposed based on thermodynamic model. In the model, nucleation of the second phase is assumed to be controlled by the effective diffusion, which involves the bulk diffusion and dislocation pipe diffusion, and growth is controlled by the bulk diffusion of forming elements. The interfacial energy of complex precipitate is calculated by the linear interpolation method, and the effects of alloying elements on precipitation behavior are manifested using weighted means of their diffusivities and concentration. The predictions were compared with the experimental measurements, and a good agreement was obtained.
基金Funded by the Major Special Science and Technology Project of Hainan Province (No.ZDZX20100009)
文摘Phase transition behavior and influence of ions on the thermo-sensitive polyamide with polyethylene glycol as the main chain were studied in detail. By measuring the light transmission rates of polymer solutions, the change of its lower critical solution temperature （LCST） in the salt solution was investigated. It was found that a reversible phase transition of the polyamide occurred at the LCST and finished in a narrow temperature range. The LCST was associated with species of ions in salt solution. Anions had a great impact on the phase transition performance of the thermo-sensitive polyamide, while the cations had a slight influence on the phase transition. Different anions had different coagulation ability to ‘salt-out＇ the polyamide. The order was： CO2-3〉SiO2-3〉HPO2-4〉OH-〉Cl-〉HCO3-〉HSOa-〉NO2-〉NO3-.
基金the National Natural Science Foundation of China(No.21704024)the Huxiang Young Talent Program from Hunan Province(No.2018RS3036)+1 种基金the Fundamental Research Funds for the Central Universities from Hunan UniversityNational Natural Science Foundation of Shandong Province(No.ZR2019QB024)。
文摘A hybrid system containing a pillar[5]arene unit and ten crown ether moieties was developed.The LCST behavior and thermo-responsive ness were successfully introduced into this pillar[5]arene-crown ether system.Both host-vip interactions and salting-out effect displayed great effects in realizing the supramolecular control over LCST properties and the rmo-re sponsiveness.Compa red with the individual macrocycles,this hybrid macrocycle system dramatically amplified the supramolecular control effect over LCST behavior.
基金Project Supported by Science Foundation of Shanghai MunicipalCommission of Science and Technology (Grant No .02DJ14030)
文摘The thermosensitive poly （ N-isopropylacrylamide ） （PNIPAAm） and poly （N-isopropylacrylamide-co-acrylamide） [ poly （NIPAAm-co-AAm） ] hydrogels with different acrylamide molar percentage are prepared by radiation polymerization using Co^60 γ-ray. Their swelling equilibrium data in the media of deionized water, NaCl aqueous solutions and different pH buffer solutions are determined. It appears that lower critical solution temperature （LCST） of the hydrogels will drop with the increase of ionic strength and increase with the rising of acrylamide content, A semi-empirical formula is set up with the experimental results. Moreover, it also indicates that this copolymer is pH-sensitive, which is similar to the homopolymer of PNIPAAm.
基金funding support from the Global STEM Professorship Scheme sponsored by the Government of Hong Kong Special Administrative RegionStart-up funding from The Chinese University of Hong Kong.
文摘CONSPECTUS:Thermoresponsive hydrogels possess an inherent capacity for autonomous adjustment of their properties in response to temperature variations,eliminating the requirement for external power sources and rendering them suitable for diverse environmental applications.Our discourse commences by establishing a foundational comprehension of the two principal categories governing thermal transitions in thermoresponsive hydrogels,namely,the Lower Critical Solution Temperature(LCST)and the Upper Critical Solution Temperature(UCST).
