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Research and development of the pulse acquisition system and the pulse biomimetic reproduction system
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作者 YI Kai MA Yunjing +2 位作者 GUO Shen LIU Heng XU Bin 《Journal of Traditional Chinese Medicine》 2025年第1期213-220,共8页
The paper is an introduction to the front-end pulse acquisition and the back-end pulse biomimetic reproduction system.This system is capable of faithfully replicating the complete pulse waveform collected at the front... The paper is an introduction to the front-end pulse acquisition and the back-end pulse biomimetic reproduction system.This system is capable of faithfully replicating the complete pulse waveform collected at the front end.Traditional Chinese Medicine(TCM)practitioners analyze and diagnose the pulse patterns at the replication end.Meanwhile,the obtained pulse waveforms are analyzed and learnt by a neural network based on key diagnostic points in TCM pulse taking,which enables the determination of the corresponding relationships between different pulse waveforms and various pulse patterns in TCM pulse taking.With the support of clinical samples,an auxiliary diagnostic system for TCM pulse patterns ensures the accuracy of pulse pattern replication. 展开更多
关键词 pulse taking medicine Chinese traditional pulse acquisition system pulse biomimetic reproduction system
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Production and magnetic self-confinement of e^(-)e^(+)plasma by an extremely intense laser pulse incident on a structured solid target
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作者 Alexander Samsonov Alexander Pukhov 《Matter and Radiation at Extremes》 2025年第5期10-19,共10页
We propose an all-optical,single-laser-pulse scheme for generating a dense relativistic strongly magnetized electron-positron pair plasma.The scheme involves the interaction of an extremely intense(I■10^(24) W/cm^(2)... We propose an all-optical,single-laser-pulse scheme for generating a dense relativistic strongly magnetized electron-positron pair plasma.The scheme involves the interaction of an extremely intense(I■10^(24) W/cm^(2))circularly polarized laser pulse with a solid-density target containing a conical cavity.Through full-scale three-dimensional particle-in-cell simulations that account for quantum electrodynamic effects,it is shown that this interaction results in two significant outcomes:first,the generation of quasi-static magnetic fields reaching tens of gigagauss,and,second,the production of large quantities of electron-positron pairs(up to 10^(13))via the Breit-Wheeler process.The e^(-)e^(+)plasma becomes trapped in the magnetic field and remains confined in a small volume for hundreds of femtoseconds,far exceeding the laser timescale.The dependence of pair plasma parameters,as well as the efficiency of plasma production and confinement,is discussed in relation to the properties of the laser pulse and the target.Realizing this scheme experimentally would enable the investigation of physical processes relevant to extreme astrophysical environments. 展开更多
关键词 polarized laser pulse intense laser pulse structured solid target quantum electrodynamic effects generation magnetic confinement electron positron plasma Breit Wheeler process
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Comprehensive study of pulse shape discrimination in a Ga-doped zinc oxide scintillating detector
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作者 Kuo Zhao Liang Chen +5 位作者 Ning Lv Lei-Dang Zhou Shi-Yi He Jin-Lu Ruan Han Wang Xiao-Ping Ouyang 《Nuclear Science and Techniques》 2025年第3期38-49,共12页
Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of ... Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of Zn O:Ga(GZO)in nuclear energy is particularly significant and fascinating at the fundamental level,enabling neutron/gamma discrimination while preserving the response time properties of the single crystal in sub-nanoseconds,maximizing the effective counting rate of the pulsed radiation field.In this study,the single-particle waveform discrimination characteristics of GZO were evaluated for five charged particles(α,β,H^(+),Li^(+),and O^(8+)and two prevalent uncharged particles(neutrons and gamma rays).Based on the timecorrelation single-photon counting(TCSPC)method,the luminescence decay time constants of the charged particles in the GZO crystal were determined as follows:1.21 ns for H^(+),1.50 ns for Li^(+),1.70 ns for O^(8+),1.56 ns forαparticles,and 1.09 ns forβparticles.Visible differences in the excitation time spectra curves were observed.Using the conventional time-domain or frequency-domain waveform discrimination techniques,waveform discrimination of 14.9 Me V neutrons and secondary gamma rays generated by the CPNG-6 device based on GZO scintillation was successfully implemented.The neutron signal constituted 77.93%of the total,indicating that GZO exhibited superior neutron/gamma discrimination sensitivity compared with that of a commercial stilbene crystal.Using the neutron/gamma screening outcomes,we reconstructed the voltage pulse height,charge height,and neutron multiplication time spectra of the pulsed neutron radiation field.The reconstructed neutron multiplication time spectrum exhibited a deviation of less than 3%relative to the result obtained using a commercial stilbene scintillator.This is the first report in the open literature on the neutron/gamma discrimination and reconstruction of Zn O pulsed radiation-field information. 展开更多
关键词 Zinc oxide Scintillation crystal pulse shape discrimination Radiation luminescence pulsed neutron radiation field
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Experimental and Peridynamic Numerical Study on the Opening Process of the Soft PSD in Pulse Solid Rocket Motors
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作者 Wenxia Cheng Qinliu Cao +1 位作者 Bin Yuan Jiale Yan 《Computer Modeling in Engineering & Sciences》 2025年第6期3197-3214,共18页
As a critical component of pulse solid rocket motors(SRMs),the soft pulse separation device(PSD)is vital in enabling multi-pulse propulsion and has become a breakthrough in SRM engineering applications.To investigate ... As a critical component of pulse solid rocket motors(SRMs),the soft pulse separation device(PSD)is vital in enabling multi-pulse propulsion and has become a breakthrough in SRM engineering applications.To investigate the opening performance of the PSD,an axial PSD incorporating a star-shaped prefabricated defect was designed.The opening process was simulated using peridynamics,yielding the strain field distribution and the corresponding failure mode.A single-opening verification test was conducted.The simulation results showed good agreement with the experimental data,demonstrating the reliability of the peridynamic modeling approach.Furthermore,the effects of the prefabricated defect shape and depth on the opening performance of the PSD were analyzed through simulation.The research results indicate that the established constitutive model and failure criteria based on peridynamics can reasonably predict the failure location and the opening pressure of the soft PSD.Under the impact loading,the weak zone of the soft PSD firstly ruptures,and the damaged area gradually propagates along with the prefabricated defect,eventually leading to complete separation.A smaller prefabricated defect depth or a wider prefabricated defect distribution can cause a reduction in opening pressure.These research results provide valuable guidance for the preliminary design and optimization of PSDs in pulse solid rocket motors. 展开更多
关键词 PERIDYNAMICS pulse solid rocket motor soft pulse separation device material failure
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Theoretical research on the effective generation of an isolated attosecond pulse from the synthesized pulse laser with optimized waveform
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作者 Kun-Zhen Zhan Yan-Ben Yin Gao Chen 《Communications in Theoretical Physics》 2025年第8期142-149,共8页
A mid-infrared femtosecond pulse laser with a single cycle and high intensity is an ideal driving light source for generating isolated attosecond pulses. Due to current experimental limitations, it is difficult to dir... A mid-infrared femtosecond pulse laser with a single cycle and high intensity is an ideal driving light source for generating isolated attosecond pulses. Due to current experimental limitations, it is difficult to directly achieve this type of laser light source in the laboratory. In this paper, we obtain such an ideal light source by adding a Ti sapphire pulse to the combined pulse laser consisting of two mid-infrared pulses. Specifically, by combining the synthesized pulse consisting of 8 fs/1200 nm/1.62 × 10^(14)W cm^(-2)and 12 fs/1800 nm/2.71 × 10^(14)W cm^(-2)with an additional 8 fs/800 nm/1.26 × 10^(14)W cm^(-2)Ti sapphire pulse, the resulting electric field waveform is very close to that of a 1170 nm femtosecond pulse with an intensity of 1.4 × 10^(15)W cm^(-2), a single-cycle pulse width, and a carrier-envelope phase of 0.25π. Numerical simulations show that both cases produce high-order harmonic emission spectra with broadband supercontinuum spectra, however, the bandwidth of the supercontinuum spectra and the harmonic intensities in the synthesized pulses are significantly better than those in the single1170 nm pulse. After inverse Fourier transform, we obtain 66 as a high-intensity isolated attosecond pulse, whose intensity is five orders of magnitude higher than that of a monochromatic field. Here, the phase differences between three combined pulse lasers have little effect on the numerical simulation results when they vary in the range of 0.3π. 展开更多
关键词 high-order harmonic attosecond pulses combined pulsed lasers single cycle
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High-sensitivity spectroscopic measurements under pulsed high magnetic field
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作者 Zheng Wang Yichun Pan +2 位作者 Guangran Yang Wei Xie Weihang Zhou 《Chinese Physics B》 2025年第7期60-65,共6页
Pulsed magnet technology is the only way to generate ultra-strong magnetic fields higher than 45 T so far.However,the inherently fast-changing field strength(typically on the order of 1000 T/s)poses significant challe... Pulsed magnet technology is the only way to generate ultra-strong magnetic fields higher than 45 T so far.However,the inherently fast-changing field strength(typically on the order of 1000 T/s)poses significant challenges for spectroscopic measurements which rely on time integration of signals to improve spectral qualities.In this work,we report high-sensitivity spectroscopic measurements under pulsed high magnetic fields employing the long flat-top pulsed magnetic field technique.By means of a multiple-capacitor power supply,we were able to generate pulsed high magnetic fields with controllable flat-top pulse width and field stabilities.By synchronizing spectroscopic measurements with the waveform of the flattop magnetic field,the integration time of each spectrum can be increased by up to 100 times compared with that of the conventional spectroscopic measurements under pulsed magnetic fields,thus enabling high-sensitivity spectroscopic measurements under ultra-strong pulsed magnetic fields.These findings promise an efficient way to significantly improve the performance and extend the application of optical measurements under pulsed high magnetic fields. 展开更多
关键词 pulsed magnet flat-top pulsed magnetic field optical spectroscopy PHOTOLUMINESCENCE
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Reconnection of magnetic flux ropes driven by two-color Laguerre–Gaussian laser pulses in plasma
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作者 Yin-Hong Liu Su-Ming Weng Zheng-Ming Sheng 《Matter and Radiation at Extremes》 2025年第4期24-34,共11页
The generation and reconnection of magneticflux ropes in a plasma irradiated by two Laguerre–Gaussian laser pulses with different frequen-cies and opposite topological charges are investigated numerically by particle-... The generation and reconnection of magneticflux ropes in a plasma irradiated by two Laguerre–Gaussian laser pulses with different frequen-cies and opposite topological charges are investigated numerically by particle-in-cell simulations.It is shown that twisted plasma currents and hence magneticflux ropes can be effectively generated as long as the laser frequency difference matches the electron plasma frequency.More importantly,subsequent reconnection of magneticflux ropes can occur.Typical signatures of magnetic reconnection,such as magnetic island formation and plasma heating,are identified in the reconnection of magneticflux ropes.Notably,it is found that a strong axial magneticfield can be generated on the axis,owing to the azimuthal current induced during the reconnection of the ropes.This indicates that in the reconnection of magneticflux ropes,the energy can be transferred not only from the magneticfield to the plasma but also from the plasma current back to the magneticfield.This work opens a new avenue to the study of magneticflux ropes,which helps in understanding magnetic topology changes,and resultant magnetic energy dissipation,plasma heating,and particle acceleration found in solarflares,and magnetic confinement fusion devices. 展开更多
关键词 twisted plasma currents laguerre gaussian laser pulses magnetic islands electron plasma frequency Laguerre Gaussian laser pulses magnetic ux ropes magnetic flux ropes plasma reconnection
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Compact self-pulsed Tm:GdScO_(3)laser with narrow pulse width
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作者 Bangzheng Liu Xiangyu Li +2 位作者 Jiahao Dong Lu Zhang Linjun Li 《Chinese Physics B》 2025年第9期234-238,共5页
A self-pulsed Tm:GdScO_(3)laser was experimentally demonstrated by using a compact linear resonant cavity.When the pump power was 19.6 W,an average output power of 1771 m W was achieved from the self-pulsed Tm:GdScO_(... A self-pulsed Tm:GdScO_(3)laser was experimentally demonstrated by using a compact linear resonant cavity.When the pump power was 19.6 W,an average output power of 1771 m W was achieved from the self-pulsed Tm:GdScO_(3)laser with a pulse width of 158.1 ns and a pulse repetition frequency of 112.8 kHz,corresponding to an optical-to-optical conversion efficiency of 9.0%.Moreover,a single pulse energy of 15.7μJ and a pulse peak power of 99.3 W were acquired from the self-pulsed Tm:GdScO_(3)laser.This is,as we know,the first time that the self-pulsed laser output at 2-μm waveband range was obtained by utilizing a Tm:GdScO_(3)crystal so far. 展开更多
关键词 self-pulsed laser Tm:GdScO_(3)crystal pulse width
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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape 被引量:1
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作者 Xuewei Zhang Wei Zhou +13 位作者 Yuming Huang Liang Xie Tonghui Li Huimin Kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo Zhao 《Journal of Energy Chemistry》 2025年第1期201-214,共14页
The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for... The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors. 展开更多
关键词 Water electrolysis Hydrogen production pulsed dynamic electrolysis Proton exchange membrane water electrolysis Mass transport
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Generation and dynamics of special mode-locked pulses in an ultrafast Er-doped fiber laser with SMF-GIMF-SMF saturable absorber 被引量:1
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作者 LIN Yingjie ZENG Qiong +3 位作者 JI Yubo SONG Yufeng WANG Ke WANG Zhenhong 《Optoelectronics Letters》 2025年第5期265-270,共6页
In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not ... In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers. 展开更多
关键词 ultrafast laser ER doped fiber SMF GIMF SMF dispersive Fourier transformation saturable absorber sa mode locked pulses nonlinear dynamics saturable absorber
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Optical transmittance and pulse shape discrimination of polystyrene/poly(methyl methacrylate)-based plastic scintillators
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作者 Yi-Yao Liang Ying-Du Liu +2 位作者 Pu-Sen Wang Jie Bao Xiao-Ping Ouyang 《Nuclear Science and Techniques》 2025年第1期94-102,共9页
Polymethyl methacrylate(PMMA)is an optically transparent thermoplastic with favorable processing conditions.In this study,a series of plastic scintillators are prepared via thermal polymerization,and the impact of PMM... Polymethyl methacrylate(PMMA)is an optically transparent thermoplastic with favorable processing conditions.In this study,a series of plastic scintillators are prepared via thermal polymerization,and the impact of PMMA content on their transparency and pulse shape discrimination(PSD)ability is investigated.The fabricated samples,comprising a polystyrene(PS)-PMMA matrix,30.0 wt%2,5-diphenyloxazole(PPO),and 0.2 wt%9,10-diphenylanthracene(DPA),exhibit high transparency with transmissivity ranging from 70.0 to 90.0%(above 415.0 nm)and demonstrate excellent n/γdiscrimination capability.Transparency increased with increasing PMMA content across the entire visible light spectrum.However,the PSD performance gradually deteriorated when the aromatic matrix was replaced with PMMA.The scintillator containing 20.0 wt%PMMA demonstrated the best stability concerning PSD properties and relative light yields. 展开更多
关键词 Neutron detection Plastic scintillation pulse shape discrimination Polymethyl-methacrylate POLYSTYRENE
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Development and validation of a nomogram model for predicting the risk of H-type hypertension with pulse diagram parameters
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作者 Siman WANG Mengchu ZHANG +4 位作者 Minghui YAO Tianxiao XIE Rui GUO Yiqin WANG Haixia YAN 《Digital Chinese Medicine》 2025年第2期174-182,共9页
Objective To develop an onset risk prediction nomogram for patients with homocysteine-type(H-type)hypertension(HTH)based on pulse diagram parameters to assist early clinical prediction and diagnosis of HTH.Methods Pat... Objective To develop an onset risk prediction nomogram for patients with homocysteine-type(H-type)hypertension(HTH)based on pulse diagram parameters to assist early clinical prediction and diagnosis of HTH.Methods Patients diagnosed with essential hypertension and admitted to Shanghai Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine,Shang-hai Hospital of Traditional Chinese Medicine,and Shanghai Hospital of Integrated Tradition-al Chinese and Western Medicine from July 6th 2020 to June 16th 2021,and from August 11th 2023 to January 22nd 2024,were enrolled in this retrospective research.The baselines and clinical biochemical indicators of patients were collected.The SMART-I TCM pulse instru-ment was applied to gather pulse diagram parameters.Multivariate logistic regression was adopted to analyze the risk factors for HTH.RStudio was employed to construct the nomo-gram model,receiver operating characteristic(ROC)curve,and calibration curve(bootstrap self-sampling 200 times),and clinical decision curve were drawn to evaluate the model’s dis-crimination and clinical effectiveness.Results A total of 168 hospitalized patients with essential hypertension were selected and di-vided into non-HTH group(n=29)and HTH group(n=139).Compared with non-HTH group,HTH group had a lower body mass index(BMI),and higher proportions of male pa-tients and drinkers(P<0.05).The ventricular wall thickening(VWT)could not be deter-mined.The proportions of left common carotid intima-media wall thickness(LCCIMWT)and serum creatinine(SCR)were higher in HTH group(P<0.05).The pulse diagram parameter As was significantly higher,and H4/H1 and T1/T were lower in HTH group(P<0.05).Gender,al-cohol consumption,serum creatinine,and the pulse diagram parameter H4/H1 were identi-fied as independent risk factors for HTH(P<0.05).The nomogram’s area under the ROC curve(AUC)was 0.795[95%confidence interval(CI):(0.7066,0.8828)],with a specificity of 0.724 and sensitivity of 0.799.After 200 times repeated bootstrap self-samplings,the calibra-tion curve showed that the simulated curve fits well with the actual curve(x^(2)=9.5002,P=0.3019).The clinical decision curve indicated that the nomogram’s applicability was optimal when the threshold for predicting HTH was between 0.38 and 1.00.Conclusion The nomogram model could be valuable for predicting the onset risk of HTH and pulse diagram parameters can facilitate early screening and prevention of HTH. 展开更多
关键词 H-type hypertension Homocysteine NOMOGRAM pulse diagram parameters Prediction model
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Diagnostic Illustrations:Integration and Changes of Western Transmission of Traditional Chinese Medicine Pulse Diagnosis Diagrams
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作者 MA Jie 《Chinese Medicine and Culture》 2025年第2期111-123,共13页
Throughout the long development of the Silk Road,traditional medical techniques from various countries have continued to intersect and integrate,and traditional Chinese medicine(TCM)has also been transmitted to Eurasi... Throughout the long development of the Silk Road,traditional medical techniques from various countries have continued to intersect and integrate,and traditional Chinese medicine(TCM)has also been transmitted to Eurasia via the Silk Road.In the process of TCM knowledge dissemination,the tangible pulse diagnosis diagrams(脉诊图)have been collected in works such as Tānksūqnāmah(《伊利汗中国科技珍宝书》Ilkhanate Chinese Science and Technology Treasure Book),Specimen Medicinae Sinicae(《中医指南》A Guide to Traditional Chinese Medicine),and Die Chinesische Medizin(《中华医学》Chinese Medicine),and has become an important carrier and cultural symbol of pulse diagnostics,integrating into Eurasian medicine.The dissemination of TCM pulse diagnosis and the pulse diagnosis diagrams are closely related to Nan Jing(《难经》The Classic of Difficult Issues)and the pulse studies of the Jin dynasty medical scholar,Wang Shuhe(王叔和).The study found that the pulse diagnosis diagrams had distinct characteristics in its transmission to the West in different eras,and they are analyzed from the perspectives of“communicators(translators)”,“translation characteristics”,“cultural background”,“inheritance system”,revealing multiple integrations and transformations of ancient TCM pulse diagnosis diagrams in the East-West exchange and mutual learning.The pulse diagnosis diagrams have gradually become a symbol of TCM diagnostic methods,forming an inseparable link between TCM and pulse diagnosis in the minds of scholars and the public in the East and West. 展开更多
关键词 pulse diagnosis diagrams TRANSLATION ACCULTURATION Medical exchange Traditional Chinese medicine
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Simulation and experimental study on the use of shaped charge jet as transient antennas for radiating electromagnetic pulses
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作者 Jiahui Guo Bin Ma +2 位作者 Zhengxiang Huang Yong Peng Xin Jia 《Defence Technology(防务技术)》 2025年第5期260-274,共15页
In this study,the potential application of shaped charge jets as transient antennas for electromagnetic signal transmission was explored and an electromagnetic pulse radiation system with a shaped charge jet as a tran... In this study,the potential application of shaped charge jets as transient antennas for electromagnetic signal transmission was explored and an electromagnetic pulse radiation system with a shaped charge jet as a transient antenna was proposed.During the research,crucial characteristics of the transient antenna formed by a shaped charge with a 30 mm diameter,such as resonant frequency,radiation pattern,and radiation efficiency,were evaluated.The typical shaped charge jet morphology was obtained based on the simulations,in which it could insight the dynamic behavior of the shaped charge jet selected.An equivalent model experiment was employed to test the radiation efficiency,and it showed that a shorting pin loading method could increase the relative bandwidth of the jet antenna to 32.8%,and the experimental results correlate with the theoretical predictions for half-wave dipole antennas reasonably well.Additionally,variations in the diameter of the shaped charge jet were found to affect the input impedance and impedance bandwidth,while the length of the jet influenced the resonant frequency of the antenna.This suggests that altering these parameters can achieve reconfigurability of the jet antenna. 展开更多
关键词 Shaped charge Transient antenna Electromagnetic pulse Radiated power Reconfigurable antenna
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Evaluation of high voltage pulse discharge in resource processing applications:A review
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作者 ZHANG Hong-hao YUAN Shuai +3 位作者 GAO Peng LI Yan-jun HAN Yue-xin DING Hao-yuan 《Journal of Central South University》 2025年第3期934-961,共28页
Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and ... Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and improving energy efficiency are crucial to advancing China’s circular economy.Mining companies are actively exploring novel and innovative technologies to significantly cut down on operating costs and minimize emissions of dust and pollutants generated during processing.Recently,high voltage pulse discharge(HVPD)technology has received widespread attention and has been reported to have good application prospects in resource processing.This paper presents an extensive review of the operational principles of HVPD and the unique characteristics it engenders,such as non-polluting,selective material fragmentation,pre-weakening,pre-concentration,and enhanced permeability of coal seams.Additionally,this review explores the potential and obstacles confronting HVPD in industrial contexts,offering fresh insights for HVPD optimization and providing guidance and prospects for industrial deployment and further development. 展开更多
关键词 resource processing high voltage pulse discharge selective fragmentation pre-weakening PRE-CONCENTRATION
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县域教育数字化转型的路径探索——基于青州“PULSE”模型的实践分析
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作者 刘德燕 马世国 《当代教育家(下半月)》 2025年第8期8-10,共3页
在人工智能与大数据技术迅猛发展的时代背景下,教育数字化转型已从工具性辅助迈向系统性生态重构。本期专题“教育数字化的基层实践探索”聚焦技术赋能教育的多维实践,收录八篇兼具理论深度与实践价值的文章。专题以青州“PULSE”模型... 在人工智能与大数据技术迅猛发展的时代背景下,教育数字化转型已从工具性辅助迈向系统性生态重构。本期专题“教育数字化的基层实践探索”聚焦技术赋能教育的多维实践,收录八篇兼具理论深度与实践价值的文章。专题以青州“PULSE”模型为重要参照,其通过政策驱动、全域覆盖、学习革命、系统创新、伦理托底的五维协同,不仅打破了城乡教育资源壁垒,更展现了县域层面从硬件铺设到生态培育的转型智慧。 展开更多
关键词 pulse模型 政策驱动 县域 全域覆盖 教育数字化转型
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Fracture propagation and fatigue damage mechanisms in pulse hydraulic fracturing of deep coal
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作者 YANG Ruiyue LU Meiquan +4 位作者 LI Ao CHENG Haojin JING Meiyang HUANG Zhongwei LI Gensheng 《Petroleum Exploration and Development》 2025年第4期1074-1085,共12页
By integrating laboratory physical modeling experiments with machine learning-based analysis of dominant factors,this study explored the feasibility of pulse hydraulic fracturing(PHF)in deep coal rocks and revealed th... By integrating laboratory physical modeling experiments with machine learning-based analysis of dominant factors,this study explored the feasibility of pulse hydraulic fracturing(PHF)in deep coal rocks and revealed the fracture propagation patterns and the mechanisms of pulsating loading in the process.The results show that PHF induces fatigue damage in coal matrix,significantly reducing breakdown pressure and increasing fracture network volume.Lower vertical stress differential coefficient(less than 0.31),lower peak pressure ratio(less than 0.9),higher horizontal stress differential coefficient(greater than 0.13),higher pulse amplitude ratio(greater than or equal to 0.5)and higher pulse frequency(greater than or equal to 3 Hz)effectively decrease the breakdown pressure.Conversely,higher vertical stress differential coefficient(greater than or equal to 0.31),higher pulse amplitude ratio(greater than or equal to 0.5),lower horizontal stress differential coefficient(less than or equal to 0.13),lower peak pressure ratio(less than 0.9),and lower pulse frequency(less than 3 Hz)promote the formation of a complex fracture network.Vertical stress and peak pressure are the most critical geological and engineering parameters affecting the stimulation effectiveness of PHF.The dominant mechanism varies with coal rank due to differences in geomechanical characteristics and natural fracture development.Low-rank coal primarily exhibits matrix strength degradation.High-rank coal mainly involves the activation of natural fractures and bedding planes.Medium-rank coal shows a coexistence of matrix strength degradation and micro-fracture connectivity.The PHF forms complex fracture networks through the dual mechanism of matrix strength degradation and fracture network connectivity enhancement. 展开更多
关键词 deep coal-rock gas pulse hydraulic fracturing coal rank fatigue damage matrix strength degradation breakdown pressure micro-fracture connectivity complex fracture network
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Pulse duration tunable ultra-narrow bandwidth mode-locked lasers
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作者 Weixi Li Lilong Dai +8 位作者 Qianqian Huang Meng Zou Xiangpeng Xiao Siyu Luo Siyu Chen Yingxiong Song Yunqi Liu Zhijun Yan Chengbo Mou 《Advanced Photonics Nexus》 2025年第3期168-175,共8页
Ultra-narrow bandwidth mode-locked lasers with tunable pulse duration can be versatile light sources for diverse applications.However,the spectral-temporal control of a narrow bandwidth mode-locked laser is challengin... Ultra-narrow bandwidth mode-locked lasers with tunable pulse duration can be versatile light sources for diverse applications.However,the spectral-temporal control of a narrow bandwidth mode-locked laser is challenging due to limited gain and nonlinearity,hindering practical applications of such lasers.We demonstrate a pulse duration widely tunable mode-locked ultra-narrow bandwidth laser using a composite filtering mechanism and a single-wall carbon nanotube.The laser pulse duration can be adjusted from 481 ps to 1.38 ns,which is the widest tuning range achieved in narrow-bandwidth passively mode-locked lasers.When the pulse duration is 1.38 ns,the corresponding spectral width reaches 4 pm(502 MHz).Numerical simulations support the experimental results and show that the evolution of long pulses in the laser cavity behaves similarly to a quasi-continuous wave with a low breathing ratio.We have not only designed a simple and flexible tunable scheme for the dilemma of spectral-temporal control in narrow-bandwidth mode-locked fiber lasers but also provided a unique and idealized light source for various applications that takes into account robust output. 展开更多
关键词 mode-locked fiber laser ultra-narrow bandwidth nanosecond pulse single-walled carbon nanotube spectral-temporal control
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Deterministic interconversion of the Greenberger-Horne-Zeilinger state and Knill-Laflamme-Milburn state via Lietransform-based pulse design in Rydberg atoms
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作者 J P Wang Y Q Ji +3 位作者 L P Yang C Q Wang L Dong X M Xiu 《Communications in Theoretical Physics》 2025年第6期67-75,共9页
Conversion between different types of entangled states is an interesting problem in quantum mechanics.But research on the conversion between the Greenberger-Horne-Zeilinger(GHZ)state and Knill-Laflamme-Milburn(KLM)sta... Conversion between different types of entangled states is an interesting problem in quantum mechanics.But research on the conversion between the Greenberger-Horne-Zeilinger(GHZ)state and Knill-Laflamme-Milburn(KLM)state in an atomic system has not been reported.In this paper,we propose a scheme to realize the interconversion(one-step)between the GHZ state and KLM state with Rydberg atoms.By utilizing Rydberg-mediated interactions,we simplify the system.By combining a Lie-transform-based pulse design,the evolution path is built up to realize interconversion of the GHZ state and KLM state.The numerical simulation result shows that the present scheme is robust against decoherence and operational imperfection. 展开更多
关键词 Rydberg atoms entangled states INTERCONVERSION pulse design
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Active learning-augmented end-to-end modeling toward fast inverse design in chirped pulse amplification
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作者 Helin Jiang Guoqing Pu +2 位作者 Xinyi Ma Weisheng Hu Lilin Yi 《Advanced Photonics Nexus》 2025年第4期154-162,共9页
To capture the nonlinear dynamics and gain evolution in chirped pulse amplification(CPA)systems,the split-step Fourier method and the fourth-order Runge–Kutta method are integrated to iteratively address the generali... To capture the nonlinear dynamics and gain evolution in chirped pulse amplification(CPA)systems,the split-step Fourier method and the fourth-order Runge–Kutta method are integrated to iteratively address the generalized nonlinear Schrödinger equation and the rate equations.However,this approach is burdened by substantial computational demands,resulting in significant time expenditures.In the context of intelligent laser optimization and inverse design,the necessity for numerous simulations further exacerbates this issue,highlighting the need for fast and accurate simulation methodologies.Here,we introduce an end-to-end model augmented with active learning(E2E-AL)with decent generalization through different dedicated embedding methods over various parameters.On an identical computational platform,the artificial intelligence–driven model is 2000 times faster than the conventional simulation method.Benefiting from the active learning strategy,the E2E-AL model achieves decent precision with only two-thirds of the training samples compared with the case without such a strategy.Furthermore,we demonstrate a multi-objective inverse design of the CPA systems enabled by the E2E-AL model.The E2E-AL framework manifests the potential of becoming a standard approach for the rapid and accurate modeling of ultrafast lasers and is readily extended to simulate other complex systems. 展开更多
关键词 chirped pulse amplification end-to-end modeling active learning inverse design
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