In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a n...In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature.展开更多
Ag3PO4 microcrystals with highly enhanced visible light photocatalytic activity are prepared by a facile and simple solid state reaction at room temperature. The composition, morphology and optical properties of the a...Ag3PO4 microcrystals with highly enhanced visible light photocatalytic activity are prepared by a facile and simple solid state reaction at room temperature. The composition, morphology and optical properties of the asprepared Ag3PO4 microcrystMs are characterized by x-ray diffraction, scanning electron microscopy and UV-vis diffuse reflectance spectra. The photocatalytie properties of Ag3PO4 are investigated by the degradation of both methylene blue and methyl orange dyes under visible light irradiation. The as-prepared Ag3PO4 microcrystals possess high photocatalytic oxygen production with the rate of 673μmolh-1g-1. Moreover, the as-prepared Ag3PO4 microcrystals show an enhanced photoelectrochemistry performance under irradiation of visible light.展开更多
We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photo...We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system.展开更多
Phototheranostics is an emerging field in synergistic antitumor therapy in which irradiation and sensitizers are combined to produce reactive oxygen species(ROS),bio-images,and high temperatures.All of these are arriv...Phototheranostics is an emerging field in synergistic antitumor therapy in which irradiation and sensitizers are combined to produce reactive oxygen species(ROS),bio-images,and high temperatures.All of these are arrived from the energy of sensitizers,which located in excited single state(S_(1)).Undeniably,the decentralization of the S_(1)population indirectly decreases the effect of each individual treatment.In this study,a strategy was proposed for enhancing the S_(1)population,and a sensitizer with mitochondrial targeting property,1,4-indolyl iodinated pyrrolo[3,2-b]pyrrole derivative(2I-TPIS),was assembled into adenosine triphosphate(ATP)-responsive nanoparticles(DPA-2I NPs)to achieve dual responses to irradiation and ultrasonication(US)for application to photo-sonodynamic therapy(PSDT).Compared with monotherapies,2I-TPIS generated more ROS in PSDT,inducing mitochondrial autophagy and apoptosis,which in turn triggered immunogenic cell death(ICD).Subsequently,DPA-2I NPs were constructed and self-assembled with the chemotherapeutic agents DPA-Cd and 2I-TPIS to achieve a triple synergistic strategy involving chemotherapy(CT)and PSDT.DPA-2I NPs exhibited absolute sensitization,intra-tumoral overexpression of ATP,and disassembly.Importantly,the biosafety and potent antitumor efficiency of the DPA-2I NP-based“PSDT+CT”therapy were revealed using a 4T1 tumor model.The study results provide insights into the design of sensitizers possessing a sufficient S_(1)population and a highly efficient tumor ablation capacity derived from molecular structural modulation,further enabling triple synergistic antitumor therapies,and expanding the clinical application of sensitizers.展开更多
Digital technology is the most dynamic frontier of contemporary global scientific and technological advancements,serving as a central driver of today’s technological progress.Ongoing R&D and deployment of digital...Digital technology is the most dynamic frontier of contemporary global scientific and technological advancements,serving as a central driver of today’s technological progress.Ongoing R&D and deployment of digital innovative technologies have rendered international competition and cooperation increasingly complex in both implications and forms.Beyond its role in accelerating technological progress,digital technology enhances state capability by adding a digital dimension to national power.It enables states that possess comparative advantages in digital R&D and deployment to gain greater influence in shaping international discourse,thereby widening the power gap among nations.展开更多
文摘In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature.
基金Supported by the Beijing Higher Education Young Elite Teacher Project under Grant No YETP1297the Fundamental Research Funds for the Central Universities under Grant No 2014MDLXYZY05+1 种基金the Undergraduate Innovative Test Program of China under Grant Nos GCCX2015110009 and BEIJ2015110024the National Natural Science Foundation of China under Grant Nos11074312 and 11374377
文摘Ag3PO4 microcrystals with highly enhanced visible light photocatalytic activity are prepared by a facile and simple solid state reaction at room temperature. The composition, morphology and optical properties of the asprepared Ag3PO4 microcrystMs are characterized by x-ray diffraction, scanning electron microscopy and UV-vis diffuse reflectance spectra. The photocatalytie properties of Ag3PO4 are investigated by the degradation of both methylene blue and methyl orange dyes under visible light irradiation. The as-prepared Ag3PO4 microcrystals possess high photocatalytic oxygen production with the rate of 673μmolh-1g-1. Moreover, the as-prepared Ag3PO4 microcrystals show an enhanced photoelectrochemistry performance under irradiation of visible light.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51132004,11474096,11604199,U1704145 and 11747101the Science and Technology Commission of Shanghai Municipality under Grant No 14JC1401500+1 种基金the Henan Provincial Natural Science Foundation of China under Grant No 182102210117the Higher Education Key Program of He’nan Province of China under Grant Nos 17A140025 and 16A140030
文摘We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system.
基金the financial support from the National Natural Science Foundation of China(Nos.U23A2089,22205159,and 22103055)Natural Science Foundation of Tianjin(No.21JCQNJC01450)Science and Technology Plans of Tianjin(Nos.22ZYJDSS00070 and 21ZYJDJC00050).
文摘Phototheranostics is an emerging field in synergistic antitumor therapy in which irradiation and sensitizers are combined to produce reactive oxygen species(ROS),bio-images,and high temperatures.All of these are arrived from the energy of sensitizers,which located in excited single state(S_(1)).Undeniably,the decentralization of the S_(1)population indirectly decreases the effect of each individual treatment.In this study,a strategy was proposed for enhancing the S_(1)population,and a sensitizer with mitochondrial targeting property,1,4-indolyl iodinated pyrrolo[3,2-b]pyrrole derivative(2I-TPIS),was assembled into adenosine triphosphate(ATP)-responsive nanoparticles(DPA-2I NPs)to achieve dual responses to irradiation and ultrasonication(US)for application to photo-sonodynamic therapy(PSDT).Compared with monotherapies,2I-TPIS generated more ROS in PSDT,inducing mitochondrial autophagy and apoptosis,which in turn triggered immunogenic cell death(ICD).Subsequently,DPA-2I NPs were constructed and self-assembled with the chemotherapeutic agents DPA-Cd and 2I-TPIS to achieve a triple synergistic strategy involving chemotherapy(CT)and PSDT.DPA-2I NPs exhibited absolute sensitization,intra-tumoral overexpression of ATP,and disassembly.Importantly,the biosafety and potent antitumor efficiency of the DPA-2I NP-based“PSDT+CT”therapy were revealed using a 4T1 tumor model.The study results provide insights into the design of sensitizers possessing a sufficient S_(1)population and a highly efficient tumor ablation capacity derived from molecular structural modulation,further enabling triple synergistic antitumor therapies,and expanding the clinical application of sensitizers.
文摘Digital technology is the most dynamic frontier of contemporary global scientific and technological advancements,serving as a central driver of today’s technological progress.Ongoing R&D and deployment of digital innovative technologies have rendered international competition and cooperation increasingly complex in both implications and forms.Beyond its role in accelerating technological progress,digital technology enhances state capability by adding a digital dimension to national power.It enables states that possess comparative advantages in digital R&D and deployment to gain greater influence in shaping international discourse,thereby widening the power gap among nations.