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Universal origin of glassy relaxation as recognized by configuration pattern matching

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National Science Review 2024年第5期11卷 343-351页

作者： Hai-Bin Yu liang Gao jia-qi Gao Konrad Samwer Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and Technology I.Physikalisches Institut Universit?t G?ttingen

Relaxation processes are crucial for understanding the structural rearrangements of liquids and amorphous materials. However, the overarching principle that governs these processes across vastly different materials remains an open question. Substantial analysis has been carried out based on the motions of individual particles. Here, as an alternative, we propose viewing the global configuration as a single entity. We introduce a global order parameter, namely the inherent structure minimal displacement(IS Dmin), to quantify the variability of configurations by a pattern-matching technique. Through atomic simulations of seven model glass-forming liquids, we unify the influences of temperature, pressure and perturbation time on the relaxation dissipation, via a scaling law between the mechanical damping factor and IS Dmin. Fundamentally,this scaling reflects the curvature of the local potential energy landscape. Our findings uncover a universal origin of glassy relaxation and offer an alternative approach to studying disordered systems.

关键词： glass transition metallic glass relaxation dynamics mechanical spectroscopy internal friction

Experimental investigation on pyrolysis products and pore structure characteristics of organic-rich shale heated by supercritical carbon dioxide

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Petroleum Science 2024年第4期21卷 2393-2406页

作者： Bai-Shuo Liu Chuan-jin Yao jia-Long qi Ya-qian Liu liang Xu jing-Xuan Hou State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China)) Ministry of Education School of Petroleum Engineering China University of Petroleum (East China)

The efficient pyrolysis and conversion of organic matter in organic-rich shale,as well as the effective recovery of pyrolysis shale oil and gas,play a vital role in alleviating energy *** state of carbon dioxide（CO2） in the pyrolysis environment of shale reservoirs is the supercritical *** unique supercritical fluid properties not only effectively heat organic matter,displace pyrolysis products and change shale pore structure,but also achieve carbon storage to a certain *** samples were made into powder and three sizes of cores,and nitrogen（N2） and supercritical carbon dioxide（ScCO2）pyrolysis experiments were performed at different final pyrolysis *** properties and mineral characteristics of the pyrolysis products were studied based on gas chromatography analysis,Xray diffraction tests,and mass spectrometry ***,the pore structure characteristics at different regions of cores before and after pyrolysis were analyzed using N2adsorption tests to clarify the impact of fracturing degree on the pyrolysis *** results indicate that the optimal pyrolysis temperature of Longkou shale is about 430℃.Compared with N2,the oil yield of ScCO2pyrolysis is *** pyrolysis oil obtained by ScCO2extraction has more intermediate fractions and higher relative molecular *** ScCO2can effectively improve the pore diameter of shale and its effect is better than that of *** micropores are produced in shale after pyrolysis,and the macropores only are generated in ScCO2pyrolysis environments with temperatures greater than 430℃.The pore structure has different development characteristics at different pyrolysis temperatures,which are mainly affected by the pressure holding of volatile matter and products *** to the surface of the core,the pore development effect inside the core is *** the decrease in core size,the pore diameter,specific surface area,and pore volume of cores all increase after pyrolysis.

关键词： Organic-rich shale Supercritical carbon dioxide In-situ pyrolysis Pore structure Core size and region

Switching Frequency Improvement of a High Speed on/off Valve Based on Pre-excitation Control Algorithm

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 94-106页

作者： qi Zhong Xiaotian Li Yongxin mao Enguang Xu Tiwei jia Yanbiao Li Huayong Yang College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic *** the switching frequency of the HSV increases,the properties of the generated discrete fluid approach those of continuous ***,a higher frequency response characteristic of HSV is the key to ensure the control accuracy of digital hydraulic ***,the current research mainly focuses on its dynamic performance,but neglect its *** paper presents a theoretical analysis demonstrating that the FRC of the HSV can be enhanced by minimizing its switching *** maximum switching frequency(MSF)is mainly determined by opening dynamic performance when HSV operates with low switching duty ratio(SDR),whereas the closing dynamic performance limits the MSF when HSV operates with high *** upon these findings,the pre-excitation control algorithm(PECA)is proposed to reduce the switching time of the HSV,and consequently enhance its *** results demonstrate that PECA shortens the opening delay time of HSV by 1.12 ms,the closing delay time by 2.54 ms,and the closing moving time by 0.47 ms in comparison to the existing advanced control *** a result,a larger MSF of 417 Hz and a wider controllable SDR range from 20%to 70%were achieved at a switching frequency of 250 ***,the proposed PFCA in this paper has been verified as an effective and promising approach for enhancing the control performance of digital hydraulic systems.

关键词： High speed on/off valve Switching frequency Pre-excitation Dynamic performance Switching duty ratio

Comparative studies on Fenton-like reactions catalyzed by Fe_(3)O_(4) loaded inside and outside halloysite nanotubes for the removal of organic pollutants

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Frontiers of Materials Science 2024年第1期18卷 15-28页

作者： Yang Li jia-qi Zhou Huan-Yan Xu Li-Min Dong mao-Chang Cao Lian-Wei Shan Li-Guo jin Xiu-Lan He Shu-Yan qi Heilongjiang Provincial Key Laboratory of CO_(2) Resource Utilization and Energy Catalytic Materials School of Materials Science and Chemical EngineeringHarbin University of Science and TechnologyHarbin 150040China

In this work,Fe_(3)O_(4) nanoparticles(NPs)loaded inside and outside halloysite nanotubes(HNTs)were prepared and developed as the heterogeneous Fenton-like catalysts for the removal of representative organic *** results indicated that the samples with Fe_(3)O_(4) NPs loaded outside the HNTs lumen(Fe_(3)O_(4)/HNTs)and inside the HNTs lumen(Fe_(3)O_(4)@HNTs)were successfully *** samples had typical magnetic hysteresis loops,while Fe_(3)O_(4)@HNTs exhibited higher magnetization *** comparative experiments showed that Fe_(3)O_(4)@HNTs had better Fenton-like catalytic ability than that of Fe_(3)O_(4)/HNTs in the degradation of various organic *** Rhodamine B(RhB)as an example,the adsorption thermodynamics and kinetics of RhB onto Fe_(3)O_(4)/HNTs and Fe_(3)O_(4)@HNTs were also *** comparative results demonstrated that the adsorption ability of Fe_(3)O_(4)/HNTs was better than that of Fe_(3)O_(4)@***,the dissolved concentration of Fe^(2+)and production amount of hydroxyl radical(·OH)in the Fe_(3)O_(4)@HNTs-H_(2)O_(2) system were significantly higher than those in the Fe_(3)O_(4)/HNTs-H_(2)O_(2) *** on aforementioned comparison,the nano-confinement effect in the Fe_(3)O_(4)@HNTs-H_(2)O_(2) system was *** work provides meaningful guidance for the cheap and convenient design of nanoreactors for Fenton-like applications.

关键词： Fe_(3)O_(4) halloysite nanotube adsorption Fenton-like reaction mechanism

Ultraviolet Photodetector based on Sr_(2)Nb_(3)O_(10) Perovskite Nanosheets

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 282-287页

作者：张斌斌 jia Mengmeng liang qi WU jinsong ZHAI Junyi 李宝文 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijin 100083China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Liquid-phase exfoliation was employed to synthesize Sr_(2)Nb_(3)O_(10) perovskite nanosheets with thicknesses down to 1.76 *** electron microscopy(TEM),atomic force microscope(AFM),X-ray photoelectron spectrometer(XPS),and other characterization techniques were used to evaluate the atomic structure and chemical composition of the exfoliated nanosheets.A UV photodetector based on individual Sr_(2)Nb_(3)O_(10) nanosheets was prepared to demonstrate the application of an ultraviolet(UV) *** UV photodetector exhibited outstanding photocurrent and responsivity with a responsivity of 3×10^(5) A·W^(-1) at 5 V bias under 280 nm illumination,a photocurrent of 60 nA,and an on/off ratio of 3×10^(2).

关键词： perovskite nanosheets liquid-phase exfoliation ultraviolet photodetector

Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand

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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： Pei-Yu Liao Yu-Quan qi Zhen Li jian-Hua jia Ming-liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

A real-time calibration method based on time-to-digital converter for accelerator timing system

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Nuclear Science and Techniques 2024年第9期35卷 127-140页

作者： qi-Hao Duan liang Ge Yan-Hao jia Jie-Yu Zhu Wei Zhang Institute of modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The high-intensity heavy-ion accelerator facility(HIAF)is a scientific research facility complex composed of multiple cas-cade accelerators of different types,which pose a scheduling problem for devices distributed over a certain range of 2 km,involving over a hundred *** white rabbit,a technology-enhancing Gigabit Ethernet,has shown the capability of scheduling distributed timing devices but still faces the challenge of obtaining real-time synchronization calibration param-eters with high *** study presents a calibration system based on a time-to-digital converter implemented on an ARM-based System-on-Chip(SoC).The system consists of four multi-sample delay lines,a bubble-proof encoder,an edge controller for managing data from different channels,and a highly effective calibration module that benefits from the SoC *** performance was evaluated with an average RMS precision of 5.51 ps by measuring the time intervals from 0 to 24,000 ps with 120,000 data for every *** design presented in this study refines the calibration precision of the HIAF timing *** eliminates the errors caused by manual calibration without efficiency loss and provides data support for fault *** can also be easily tailored or ported to other devices for specific applications and provides more space for developing timing systems for particle accelerators,such as white rabbits on HIAF.

关键词： HIAF White rabbit Calibration system Time-to-digital converter(TDC)

Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation

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Journal of Geriatric Cardiology 2024年第2期21卷 200-210页

作者： qing YAN jia-qi liang Yi-De YUAN Yuan LI jia-Li FAN Wen-Huan WU Pan XU jia-Hong XUE Department of Cardiovascular Medicine the Second Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina Department of Cardiovascular Medicine Zichang People’s HospitalShaanxiChina Department of Ultrasound Xijing HospitalAir Force Military Medical UniversityShaanxiChina

BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin *** study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an jiaotong University were included in this *** participants were grouped based on cumulative TyG index values tertiles within 3 months after *** regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF *** predictive value of all risk factors was assessed by receiver operating curve *** There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values *** adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,P<0.001)had a higher risk of AF recurrence than those in the low cumulative TyG index *** restricted cubic spline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index *** considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after *** longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence.

关键词： atrial fibrillation index

Chiral quantum heating and cooling with an optically controlled ion

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Light(Science & Applications) 2024年第7期13卷 1393-1400页

作者： jin-Tao Bu jian-qi Zhang Ge-Yi Ding jia-Chong Li jia-Wei Zhang Bin Wang Wen-qiang Ding Wen-Fei Yuan liang Chen qi Zhong Ali Keçebaş Şahin KÖzdemir Fei Zhou Hui jing Mang Feng State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of Sciences430071 WuhanChina. University of the Chinese Academy of Sciences 100049 BeijingChina. Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology511458 GuangzhouChina. Department of Engineering Science and Mechanics and Materials Research InstitutePennsylvania State UniversityUniversity ParkState CollegePA 16802USA. Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University410081 ChangshaChina. Department of Physics Zhejiang Normal University321004 JinhuaChina

Quantum heat engines and refrigerators are open quantum systems,whose dynamics can be well understood using a non-Hermitian formalism.A prominent feature of non-Hermiticity is the existence of exceptional points(EPs),which has no counterpart in closed quantum *** has been shown in classical systems that dynamical encirclement in the vicinity of an EP,whether the loop includes the EP or not,could lead to chiral mode ***,we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs(LEPs),which include the effects of quantum jumps and associated noise—an important quantum feature not present in previous *** demonstrate,using a Paul-trapped ultracold ion,the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an *** witness the cycling direction to be associated with the chirality and heat release(absorption)of the quantum heat engine(quantum refrigerator).Our experiments have revealed that not only the adiabaticity breakdown but also the Landau–Zener–Stückelberg process play an essential role during dynamic encircling,resulting in chiral thermodynamic *** observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

关键词： quantum chiral dynamical