Hydrogels show versatile properties and are of great interest in the fields of bioelectronics and tissue engineering.Understanding the dynamics of the water molecules trapped in the three-dimensional polymeric network...Hydrogels show versatile properties and are of great interest in the fields of bioelectronics and tissue engineering.Understanding the dynamics of the water molecules trapped in the three-dimensional polymeric networks of the hydrogels is crucial to elucidate their mechanical and swelling properties at the molecular level.In this report,the poly(DMAEMA-co-AA)hydrogels were synthesized and characterized by the macroscopic swelling measurements under different pH conditions.Furthermore,the microscopic structural dynamics of pH stimulus-responsive hydrogels were studied using FTIR and ultrafast IR spectroscopies from the viewpoint of the SCN-anionic solute as the local vibrational reporter.Ultrafast IR spectroscopic measurements showed the time constants of the vibrational population decay of SCN-were increased from 14±1 ps to 20±1 ps when the pH of the hydrogels varied from2.0 to 12.0.Rotational anisotropy measurements further revealed that the rotation of SCNanionic probe was restricted by the three-dimensional network formed in the hydrogels and the rotation of SCN-anionic probe cannot decay to zero especially at the pH of 7.0.These results are expected to provide a molecular-level understanding of the microscopic structure of the cross-linked polymeric network in the pH stimulus-responsive hydrogels.展开更多
位于甲型流感病毒包膜下的基质蛋白M1(Matrix protein 1,M1),可以与病毒包膜上的血凝素、神经氨酸酶和病毒遗传物质发生相互作用,在病毒生命周期的许多阶段起着关键作用。在病毒进入宿主细胞和出芽的过程中,M1多聚体的稳定性受到细胞环...位于甲型流感病毒包膜下的基质蛋白M1(Matrix protein 1,M1),可以与病毒包膜上的血凝素、神经氨酸酶和病毒遗传物质发生相互作用,在病毒生命周期的许多阶段起着关键作用。在病毒进入宿主细胞和出芽的过程中,M1多聚体的稳定性受到细胞环境的严格调控。因此,揭示基质蛋白寡聚体的热力学特征及其稳定性的主要贡献因素,对于设计以基质蛋白为靶向的抗流感药物具有重要意义。本文基于流感病毒在进入宿主细胞过程中所经历的环境条件,通过标准分子动力学、拉伸模拟和伞形采样模拟,研究不同pH条件下M1二聚体的热力学性质及其稳定性。结果表明,酸性环境对M1二聚体的热力学稳定性和解离过程有显著影响,二聚体接触面上酸性残基的质子化能够降低其结合能。这些发现揭示了流感病毒在感染过程中环境因素对基质蛋白组装调控的分子机制。展开更多
Dynamic simulation approach can be used for understanding the nonlinear behavior in mineral processing circuits. In this study, the gel point, the main parameters of batch flux density function and the main parameters...Dynamic simulation approach can be used for understanding the nonlinear behavior in mineral processing circuits. In this study, the gel point, the main parameters of batch flux density function and the main parameters of effective solid stress were determined at different conditions (pH, flocculant dosage and particle size). Therefore, the main parameters of phenome no logical model of sedimentation and thickening were determined as a functio n of particle size, pH and flocculant dosages using the result of experimental tests and Curve expert professional software. Then, the dynamic simulation was carried out for the industrial thickener of coal washing plant and the time-dependent variation of response variables was investigated by time-dependent variation of pH of input feed to thickener using the obtained equations. It was observed that it is possible to predict the thickener behavior as a function of time for time dependent variation of pH of input feed to the thickener of coal washing plant using obtained equations that it was not possible using phenomenological model of thickener alone.展开更多
In order to explore the influence of rainfall on the release of heavy metal Cadmium(Cd)in soil in a coal-mining area,soil column leaching experiments were carried out by simulating 3 types of rainfall(acid rain,normal...In order to explore the influence of rainfall on the release of heavy metal Cadmium(Cd)in soil in a coal-mining area,soil column leaching experiments were carried out by simulating 3 types of rainfall(acid rain,normal rainfall,and actual rainfall)with 5 different pH values(4,5,6,6.7,7),and 65 groups of data about leachate pH value and Cd concentration were obtained respectively.The results indicate the general change rule of Cd concentration in leachate:(1)the easiness of Cd release is negatively correlated to the pH value of leaching solution and positively correlated the leaching amount;(2)leaching solution with lower pH values shows more obvious release stages.Leached by solution with different pH values,the release of Cd in soil ranks as follows:Acid rain group>normal rainfall group>actual rainfall group.In the first stage,the acidity of rainfall has a significant impact on the release of Cd in soil,but in the second stage,the release of Cd is alleviated due to the soil buffering.Among the four dynamic equations to simulate the release of Cd in soil,the modified Elovich equation can describe the process most accurately,with the highest coefficient of determination R2 of 0.9975.These results can serve as a reference for further study on the migration,transformation and enrichment of Cd in soil.展开更多
基金supported by the National Natural Science Foundation of China(No.21873062)the Fundamental Research Funds for the Central Universities(GK202001009)+2 种基金the Natural Science Basis Research Plan in Shaanxi Province of China(No.2020JM-295)the 111 Project(B14041)Program for Changjiang Scholars and the Innovative Research Team in University(IRT-14R33)。
文摘Hydrogels show versatile properties and are of great interest in the fields of bioelectronics and tissue engineering.Understanding the dynamics of the water molecules trapped in the three-dimensional polymeric networks of the hydrogels is crucial to elucidate their mechanical and swelling properties at the molecular level.In this report,the poly(DMAEMA-co-AA)hydrogels were synthesized and characterized by the macroscopic swelling measurements under different pH conditions.Furthermore,the microscopic structural dynamics of pH stimulus-responsive hydrogels were studied using FTIR and ultrafast IR spectroscopies from the viewpoint of the SCN-anionic solute as the local vibrational reporter.Ultrafast IR spectroscopic measurements showed the time constants of the vibrational population decay of SCN-were increased from 14±1 ps to 20±1 ps when the pH of the hydrogels varied from2.0 to 12.0.Rotational anisotropy measurements further revealed that the rotation of SCNanionic probe was restricted by the three-dimensional network formed in the hydrogels and the rotation of SCN-anionic probe cannot decay to zero especially at the pH of 7.0.These results are expected to provide a molecular-level understanding of the microscopic structure of the cross-linked polymeric network in the pH stimulus-responsive hydrogels.
文摘位于甲型流感病毒包膜下的基质蛋白M1(Matrix protein 1,M1),可以与病毒包膜上的血凝素、神经氨酸酶和病毒遗传物质发生相互作用,在病毒生命周期的许多阶段起着关键作用。在病毒进入宿主细胞和出芽的过程中,M1多聚体的稳定性受到细胞环境的严格调控。因此,揭示基质蛋白寡聚体的热力学特征及其稳定性的主要贡献因素,对于设计以基质蛋白为靶向的抗流感药物具有重要意义。本文基于流感病毒在进入宿主细胞过程中所经历的环境条件,通过标准分子动力学、拉伸模拟和伞形采样模拟,研究不同pH条件下M1二聚体的热力学性质及其稳定性。结果表明,酸性环境对M1二聚体的热力学稳定性和解离过程有显著影响,二聚体接触面上酸性残基的质子化能够降低其结合能。这些发现揭示了流感病毒在感染过程中环境因素对基质蛋白组装调控的分子机制。
文摘Dynamic simulation approach can be used for understanding the nonlinear behavior in mineral processing circuits. In this study, the gel point, the main parameters of batch flux density function and the main parameters of effective solid stress were determined at different conditions (pH, flocculant dosage and particle size). Therefore, the main parameters of phenome no logical model of sedimentation and thickening were determined as a functio n of particle size, pH and flocculant dosages using the result of experimental tests and Curve expert professional software. Then, the dynamic simulation was carried out for the industrial thickener of coal washing plant and the time-dependent variation of response variables was investigated by time-dependent variation of pH of input feed to thickener using the obtained equations. It was observed that it is possible to predict the thickener behavior as a function of time for time dependent variation of pH of input feed to the thickener of coal washing plant using obtained equations that it was not possible using phenomenological model of thickener alone.
基金This work was supported by the Major Scienceand Technology Projects (No. 80303-AZP005)Key R & D Project (No. 2018SZ0290)AppliedBasic Research Project (No. 2018JY0425) of theScience and Technology Planning Project of SichuanProvince, China.
文摘In order to explore the influence of rainfall on the release of heavy metal Cadmium(Cd)in soil in a coal-mining area,soil column leaching experiments were carried out by simulating 3 types of rainfall(acid rain,normal rainfall,and actual rainfall)with 5 different pH values(4,5,6,6.7,7),and 65 groups of data about leachate pH value and Cd concentration were obtained respectively.The results indicate the general change rule of Cd concentration in leachate:(1)the easiness of Cd release is negatively correlated to the pH value of leaching solution and positively correlated the leaching amount;(2)leaching solution with lower pH values shows more obvious release stages.Leached by solution with different pH values,the release of Cd in soil ranks as follows:Acid rain group>normal rainfall group>actual rainfall group.In the first stage,the acidity of rainfall has a significant impact on the release of Cd in soil,but in the second stage,the release of Cd is alleviated due to the soil buffering.Among the four dynamic equations to simulate the release of Cd in soil,the modified Elovich equation can describe the process most accurately,with the highest coefficient of determination R2 of 0.9975.These results can serve as a reference for further study on the migration,transformation and enrichment of Cd in soil.
