Spaceborne optomechanical systems face the dual challenges of extreme thermal disturbances and millikelvin-level temperature control precision during orbital operations,demanding robust control strategies.To address t...Spaceborne optomechanical systems face the dual challenges of extreme thermal disturbances and millikelvin-level temperature control precision during orbital operations,demanding robust control strategies.To address the performance limitations of conventional fixed-parameter active disturbance rejection control(ADRC)under complex operating conditions,this work proposes a Qlearning-enhanced adaptive ADRC framework.A thermal-transfer model incorporating multisource disturbances(solar radiation,structural conduction,and contact thermal resistance)is established,coupled with a reinforcement learning-driven parameter optimization mechanism.The ε-greedy policy dynamically adjusts observer bandwidth(ω_(o)∈[0.01,0.2])and controller bandwidth(ω_(c)∈[0.01,0.1])to enable real-time estimation and compensation of total disturbances.Simulation results demonstrate significant improvements over fixed-parameter ADRC and a self-tuning internal model control proportional-integral(SIMC-PI)controller:31.3% and 15.4% reduction in settling time during setpoint responses,respectively;21.8% lower integral absolute error(IAE)than the fixed-parameter ADRC during setpoint step responses;12.7% and 52.5% enhancement in control precision over conventional fixed-parameter and SIMC-PI controllers,respectively,under±10 K periodic and step thermal disturbances.Monte Carlo robustness tests reveal smaller fluctuation ranges of IAE,settling time,and overshoot under±5% parameter perturbations.This methodology establishes a new paradigm for millikelvin-level thermal control in space optical payloads.展开更多
Precise temperature control to decrease movements in positions due to thermal expansion of work pieces is required in the manufacturing processes to achieve nanometer-order accuracy. We analytically examined the effec...Precise temperature control to decrease movements in positions due to thermal expansion of work pieces is required in the manufacturing processes to achieve nanometer-order accuracy. We analytically examined the effect of a method of minimizing movements in positions on a plate with varying generation of noise-heat. Control by monitoring temperature changes caused larger movements in positions than that without control because maximum change in temperature occurred at non-monitoring positions. The best method of minimizing movements in positions due to thermal expansion of a plate with varying generation of noise-heat was model predictive control by the monitoring movements and distributed temperature changes in the control heater according to the effects of the generation of noise-heat. The maximum movement in positions was 6 nm, which was 1/4 times of that without control.展开更多
The field of molecule magnets has advanced significantly in recent years.Yet,key challenges persist for their practical applications,such as achieving higher blocking temperatures and maintaining precise temperature c...The field of molecule magnets has advanced significantly in recent years.Yet,key challenges persist for their practical applications,such as achieving higher blocking temperatures and maintaining precise temperature control in air-stable magnets.This work addresses aspects related to both challenges.Thus,it presents the air-stable hexagonal bipyramidal compound{[Dy(L^(N6en))(OSiPh_(3))_(2)](BPh_(4))}·1.5CH_(2)Cl_(2)(1·1.5CH_(2)Cl_(2))and its diluted analogue{[Dy_(0.1)Y_(0.9)(L^(N6en))(OSiPh_(3))_(2)](BPh_(4))}·1.5CH_(2)Cl_(2)(1@Y·1.5CH_(2)Cl_(2)).Their high axiality,achieved by reducing equatorial charge,enables magnetic behaviour with energy barriers higher than 1500 K and blocking temperatures based on hysteresis(T_(B)^(H))of 12 and 40 K,respectively.Hence,1@Y·1.5CH_(2)Cl_(2) is the SMM with the highest T_(B)^(H) reported among air-stable uncapsulated molecule magnets.Besides,both complexes show temperature-dependent luminescence.Remarkably,1@Y·1.5CH_(2)Cl_(2) stands out as the pioneering example of a bifunctional molecule magnet and luminescent thermometer with both functionalities active below its T_(B)^(H).This breakthrough makes it possible to monitor the temperature of a molecule in the range where it exhibits remanent magnetization for the first time.Moreover,this molecular material presents by far the best magnetic characteristics(U_(eff) and T_(B)^(H))of any SMM luminescent thermometer reported to date.Experimental magnetic and luminescent data are analysed using theoretical calculations.Notably,luminescence is interpreted via coupled cluster methods,offering a more sophisticated alternative to the traditional time-dependent DFT approach.展开更多
We demonstrate an ultralow-noise single-photon detection system based on a sensitive photomultiplier tube（PMT） with precise temperature control, which can capture fast single photons with intervals around 10 ns.By i...We demonstrate an ultralow-noise single-photon detection system based on a sensitive photomultiplier tube（PMT） with precise temperature control, which can capture fast single photons with intervals around 10 ns.By improvement of the electromagnetic shielding and introduction of the self-differencing method, the dark counts（DCs） are cut down to ~1%. We further develop an ultra-stable PMT cooling subsystem and observe that the DC goes down by a factor of 3.9 each time the temperature drops 10°C. At -20°C it is reduced 400 times with respect to the room temperature（25°C）, that is, it becomes only 2 counts per second, which is on par with the superconducting nanowire detectors. Meanwhile, despite a 50% loss, the detection efficiency is still 13%. Our detector is available for ultra-precise single-photon detection in environments with strong electromagnetic disturbances.展开更多
It becomes faster and faster of the telecommunication development with the wireless technology evaluation.The communication between each other becomes more and more popular and widely,it already is one indispensable p...It becomes faster and faster of the telecommunication development with the wireless technology evaluation.The communication between each other becomes more and more popular and widely,it already is one indispensable part of our life.The wireless coverage is the key parts to supply service for subscribers.How to build the wireless site in different scenarios,such as urban,suburban,high railway,remote areas,etc?It will be discussed and proposed in this paper.Our vision is that to make better service for the general radio service for the people.展开更多
Introduction The high-energy photon source,which has been built in Huairou,Beijing,has high requirements on magnetic field dithering.Magnetic field dithering is mainly determined by the stability of the output current...Introduction The high-energy photon source,which has been built in Huairou,Beijing,has high requirements on magnetic field dithering.Magnetic field dithering is mainly determined by the stability of the output current of the power supply.In order to ensure the stability of the output current of quadrupole magnet power supply,the power supply sampling control loop needs to be precisely designed.In this paper,a precision ADC sampling system based on internal temperature control is designed to carry out precise control of the sampling ADC.Materials In this design,precise ADC chip is used to complete the precise sampling of the system.The precise sampling system contains a DAC system for high-speed settings.Methods In order to verify the design of the system,high-precision quadrupolemagnet power supply is used for measurement.Conclusion The experimental results show that the temperature variation range of precision temperature control ADC system is±0.1°C.By using the precise temperature controlADCsystem,the output current stability of the high-precision quadrupole magnet power supply is effectively improved.展开更多
Thermoelectric conversion technology,capable of directly converting heat into electricity and vice versa,plays a crucial role in both energy supply and temperature control[1].This is particularly crucial in specialize...Thermoelectric conversion technology,capable of directly converting heat into electricity and vice versa,plays a crucial role in both energy supply and temperature control[1].This is particularly crucial in specialized fields,such as deep-space exploration where solar power is ineffective,as well as in miniaturized precision temperature control applications[2].展开更多
Although photothermal therapy(PTT) has emerged as an appealing strategy for cancer treatment, the development of photothermal agents capable of precisely controlling temperature remains a challenge. In this paper, we ...Although photothermal therapy(PTT) has emerged as an appealing strategy for cancer treatment, the development of photothermal agents capable of precisely controlling temperature remains a challenge. In this paper, we present a novel synthetic photosensitizer based on a sulfur-substituted hemicyanine. It was discovered that replacing an oxygen atom in a hemicyanine derivative with a sulfur atom significantly enhances photothermal efficiency and enables lysosome targeting in cancer cells.More importantly, because of the rigid planer structure of the sulfur-substituted hemicyanine, which differs from traditional photothermal agents(PTAs) based on twisted intramolecular charge transfer(TICT) or group rotation mechanisms, the efficiency of photothermal conversion is not affected by intracellular viscosity, allowing precise temperature control during PTT.Further modifying the agent with a glutathione-responsive moiety allows the PTAs to be activated only in cancer cells. The newly proposed PTA achieves efficient PTT in a tumor-bearing mouse model while having negligible toxic side effects on healthy tissues.展开更多
基金The National Key R&D Program of China(No.2022YFB3902902)the National Natural Science Foundation of China(No.52276003).
文摘Spaceborne optomechanical systems face the dual challenges of extreme thermal disturbances and millikelvin-level temperature control precision during orbital operations,demanding robust control strategies.To address the performance limitations of conventional fixed-parameter active disturbance rejection control(ADRC)under complex operating conditions,this work proposes a Qlearning-enhanced adaptive ADRC framework.A thermal-transfer model incorporating multisource disturbances(solar radiation,structural conduction,and contact thermal resistance)is established,coupled with a reinforcement learning-driven parameter optimization mechanism.The ε-greedy policy dynamically adjusts observer bandwidth(ω_(o)∈[0.01,0.2])and controller bandwidth(ω_(c)∈[0.01,0.1])to enable real-time estimation and compensation of total disturbances.Simulation results demonstrate significant improvements over fixed-parameter ADRC and a self-tuning internal model control proportional-integral(SIMC-PI)controller:31.3% and 15.4% reduction in settling time during setpoint responses,respectively;21.8% lower integral absolute error(IAE)than the fixed-parameter ADRC during setpoint step responses;12.7% and 52.5% enhancement in control precision over conventional fixed-parameter and SIMC-PI controllers,respectively,under±10 K periodic and step thermal disturbances.Monte Carlo robustness tests reveal smaller fluctuation ranges of IAE,settling time,and overshoot under±5% parameter perturbations.This methodology establishes a new paradigm for millikelvin-level thermal control in space optical payloads.
文摘Precise temperature control to decrease movements in positions due to thermal expansion of work pieces is required in the manufacturing processes to achieve nanometer-order accuracy. We analytically examined the effect of a method of minimizing movements in positions on a plate with varying generation of noise-heat. Control by monitoring temperature changes caused larger movements in positions than that without control because maximum change in temperature occurred at non-monitoring positions. The best method of minimizing movements in positions due to thermal expansion of a plate with varying generation of noise-heat was model predictive control by the monitoring movements and distributed temperature changes in the control heater according to the effects of the generation of noise-heat. The maximum movement in positions was 6 nm, which was 1/4 times of that without control.
基金supported by Universidade de Santiago de Compostela(2024-PU027-1)Consellería de Cultura,Educación,Formación Profesional e Universidades,Xunta de Galicia(convenio 2023-1298)+3 种基金by Portuguese funds through the FCT/MCTES(PIDDAC)(UIDB/50011/2020,https://doi.org/10.54499/UIDB/50011/2020,UIDP/50011/2020,https://doi.org/10.54499/UIDP/50011/2020,and LA/P/0006/2020,https://doi.org/10.54499/LA/P/0006/2020 projects of the CICECO-Aveiro Institute of Materials)by Ministerio de Ciencia,Innovación y Universidades(PID2021-122464NB-I00 and Maria de Maeztu CEX2021-001202-M).COST Action CA22131,supported by COST(European Cooperation in Science and Technology)Xunta de Galicia for his postdoctoral fellowship(ED481B-2022-068).the Generalitat de Catalunya for the 2021-SGR-00286 grantE.R.for an ICREA Academia grant.
文摘The field of molecule magnets has advanced significantly in recent years.Yet,key challenges persist for their practical applications,such as achieving higher blocking temperatures and maintaining precise temperature control in air-stable magnets.This work addresses aspects related to both challenges.Thus,it presents the air-stable hexagonal bipyramidal compound{[Dy(L^(N6en))(OSiPh_(3))_(2)](BPh_(4))}·1.5CH_(2)Cl_(2)(1·1.5CH_(2)Cl_(2))and its diluted analogue{[Dy_(0.1)Y_(0.9)(L^(N6en))(OSiPh_(3))_(2)](BPh_(4))}·1.5CH_(2)Cl_(2)(1@Y·1.5CH_(2)Cl_(2)).Their high axiality,achieved by reducing equatorial charge,enables magnetic behaviour with energy barriers higher than 1500 K and blocking temperatures based on hysteresis(T_(B)^(H))of 12 and 40 K,respectively.Hence,1@Y·1.5CH_(2)Cl_(2) is the SMM with the highest T_(B)^(H) reported among air-stable uncapsulated molecule magnets.Besides,both complexes show temperature-dependent luminescence.Remarkably,1@Y·1.5CH_(2)Cl_(2) stands out as the pioneering example of a bifunctional molecule magnet and luminescent thermometer with both functionalities active below its T_(B)^(H).This breakthrough makes it possible to monitor the temperature of a molecule in the range where it exhibits remanent magnetization for the first time.Moreover,this molecular material presents by far the best magnetic characteristics(U_(eff) and T_(B)^(H))of any SMM luminescent thermometer reported to date.Experimental magnetic and luminescent data are analysed using theoretical calculations.Notably,luminescence is interpreted via coupled cluster methods,offering a more sophisticated alternative to the traditional time-dependent DFT approach.
基金supported by the National Natural Science Foundation of China(Nos.11574026 and 11274037)the Program for New Century Excellent Talents in University,MOE of China(No.NCET-12-0765)the Foundation for the Author of National Excellent Doctoral Dissertation,China(No.201236)
文摘We demonstrate an ultralow-noise single-photon detection system based on a sensitive photomultiplier tube（PMT） with precise temperature control, which can capture fast single photons with intervals around 10 ns.By improvement of the electromagnetic shielding and introduction of the self-differencing method, the dark counts（DCs） are cut down to ~1%. We further develop an ultra-stable PMT cooling subsystem and observe that the DC goes down by a factor of 3.9 each time the temperature drops 10°C. At -20°C it is reduced 400 times with respect to the room temperature（25°C）, that is, it becomes only 2 counts per second, which is on par with the superconducting nanowire detectors. Meanwhile, despite a 50% loss, the detection efficiency is still 13%. Our detector is available for ultra-precise single-photon detection in environments with strong electromagnetic disturbances.
文摘It becomes faster and faster of the telecommunication development with the wireless technology evaluation.The communication between each other becomes more and more popular and widely,it already is one indispensable part of our life.The wireless coverage is the key parts to supply service for subscribers.How to build the wireless site in different scenarios,such as urban,suburban,high railway,remote areas,etc?It will be discussed and proposed in this paper.Our vision is that to make better service for the general radio service for the people.
文摘Introduction The high-energy photon source,which has been built in Huairou,Beijing,has high requirements on magnetic field dithering.Magnetic field dithering is mainly determined by the stability of the output current of the power supply.In order to ensure the stability of the output current of quadrupole magnet power supply,the power supply sampling control loop needs to be precisely designed.In this paper,a precision ADC sampling system based on internal temperature control is designed to carry out precise control of the sampling ADC.Materials In this design,precise ADC chip is used to complete the precise sampling of the system.The precise sampling system contains a DAC system for high-speed settings.Methods In order to verify the design of the system,high-precision quadrupolemagnet power supply is used for measurement.Conclusion The experimental results show that the temperature variation range of precision temperature control ADC system is±0.1°C.By using the precise temperature controlADCsystem,the output current stability of the high-precision quadrupole magnet power supply is effectively improved.
基金supported by the National Key Research and Development Program of China(2024YFA1210400)the National Science Fund for Distinguished Young Scholars(52525101)+3 种基金the National Natural Science Foundation of China(52450001 and 22409014)the International Cooperation and Exchange of the National Natural Science Foundation of China(52411540237)the Tencent Xplorer Prize.Bingchao Qin acknowledges support from the China National Postdoctoral Program for Innovative Talents(BX20230456)China Postdoctoral Science Foundation(2024M754057).
文摘Thermoelectric conversion technology,capable of directly converting heat into electricity and vice versa,plays a crucial role in both energy supply and temperature control[1].This is particularly crucial in specialized fields,such as deep-space exploration where solar power is ineffective,as well as in miniaturized precision temperature control applications[2].
基金supported by the National Natural Science Foundation of China(21925802,21878039,22022803,22078046)the NSFC-Liaoning United Fund(U1908202)the National Key Research and Development Plan(2018AAA0100301)。
文摘Although photothermal therapy(PTT) has emerged as an appealing strategy for cancer treatment, the development of photothermal agents capable of precisely controlling temperature remains a challenge. In this paper, we present a novel synthetic photosensitizer based on a sulfur-substituted hemicyanine. It was discovered that replacing an oxygen atom in a hemicyanine derivative with a sulfur atom significantly enhances photothermal efficiency and enables lysosome targeting in cancer cells.More importantly, because of the rigid planer structure of the sulfur-substituted hemicyanine, which differs from traditional photothermal agents(PTAs) based on twisted intramolecular charge transfer(TICT) or group rotation mechanisms, the efficiency of photothermal conversion is not affected by intracellular viscosity, allowing precise temperature control during PTT.Further modifying the agent with a glutathione-responsive moiety allows the PTAs to be activated only in cancer cells. The newly proposed PTA achieves efficient PTT in a tumor-bearing mouse model while having negligible toxic side effects on healthy tissues.
