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Narrative review of latest research progress about robotic percutaneous coronary intervention

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Journal of Geriatric Cardiology 2024年第8期21卷 816-825页

作者： zhen-Yu LIU Guang-Yao ZHAI Department of Clinical Medicine Beijing Luhe HospitalCapital Medical UniversityBeijingChina Department of Cardiology Beijing Luhe HospitalCapital Medical UniversityBeijingChina

Robotic percutaneous coronary intervention(R-PCI)is a novel technology in which operators can manipulate guidewires and catheter devices in interventional *** approach provides great benefits to interventional cardiologists in terms of reducing both radiation exposure and orthopedic *** large,high-quality cohort studies have confirmed the short-term safety and high technical success rate of ***,randomized long-term data are still needed before adopting them as part of standard coronary ***,tele-stenting for complex coronary lesions has significant potential for *** need to overcome the present relevant challenges for its application such as inherent delays,bedside care for unstable patients from R-PCIs to manual PCIs(M-PCIs),incompatibility for a thrombus aspiration catheter and heavily calcified *** is a great future in laboratory workflow teams,3.-printed anatomical models and multiple joint collaborative control *** narrative review summarizes the latest developments in R-PCI,with a focus on developments in robotic technology,and discusses the current and future potential use of R-PCI in clinical practice globally.

关键词： coronary injuries unstable

Energy-Preserving Parareal-RKN Algorithms for Hamiltonian Systems

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 121-144页

作者： zhen Miao Bin Wang Yaolin Jiang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072P.R.China School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049P.R.China

In this paper,we formulate and analyse a kind of parareal-RKN algo-rithms with energy conservation for Hamiltonian *** proposed algorithms are constructed by using the ideas of parareal methods,Runge-Kutta-Nystr¨om(RKN)methods and projection *** is shown that the algorithms can exactly pre-serve the energy of Hamiltonian ***,the convergence of the integra-tors is rigorously *** numerical experiments are carried out to support the theoretical results presented in this paper and show the numerical behaviour of the derived algorithms.

关键词： Parareal methods Runge-Kutta-Nystr¨om methods Hamiltonian systems energy conservation

Scaling Laws Behind Penetrative Turbulence:History and Perspectives

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Advances in Atmospheric Sciences 2024年第10期41卷 1881-1900页

作者： Zijing DING Ruiqi HUANG zhen OUYANG School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150006China

An unstably stratified flow entering into a stably stratified flow is referred to as penetrative convection,which is crucial to many physical processes and has been thought of as a key factor for extreme weather *** theoretical,numerical,and experimental studies on penetrative convection are reviewed,along with field studies providing insights into turbulence *** physical factors that initiate penetrative convection,including internal heat sources,nonlinear constitutive relationships,centrifugal forces and other complicated factors are ***-edge methods for understanding transport mechanisms and statistical properties of penetrative turbulence are also documented,e.g.,the variational approach and quasilinear approach,which derive scaling laws embedded in penetrative *** these scaling laws in penetrative convection can improve our understanding of large-scale geophysical and astrophysical *** better the model of penetrative turbulence towards a practical situation,new directions,e.g.,penetrative convection in spheres,and radiation-forced convection,are proposed.

关键词： thermal convection penetrative convection scaling law turbulence

Lanthanide-based microlasers:Synthesis,structures,and biomedical applications

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Nano Research 2024年第1期17卷 97-111页

作者： Qian Zhang Yawei Liu kai Liu Hongjie Zhang Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Xiangfu Laboratory Jiaxing 314102China

The large size of lasers limits their applications in confined spaces,such as in biosensing and in vivo brain tissue *** this regard,micron-sized lasers have been *** exhibit great potential for biological detecting,remote sensing,and depth tracking due to their small sizes,sensitive properties of their spectral fingerprints,and flexible positional modulation in the ***-based luminescent materials that possess long excited-state lifetime,narrow emission bandwidth,and upconversion behaviors are promising as gain mediums for novel *** addition,lanthanide-based microlasers could be generated under natural ambient conditions with pumped or continuous light sources,which significantly promotes the practical applications of *** progress in the design,synthesis,and biomedical applications of lanthanide-based microlasers has been outlined in this *** ions doped and upconverted lanthanide-based microlasers are highlighted,which exhibit advantageous structures,miniaturized dimensions,and high lasing *** applications of lanthanide-based microlasers are further discussed,the upconverted microlasers show great advantages for biological applications owing to their tunable excitation and emission characteristics and excellent environmental ***,perspectives and challenges in the field of lanthanide-based microlasers are presented.

关键词： microlasers lanthanide-based luminescent materials upconversion nanoparticles biological applications

Thermal Decomposition and Oxidative Decomposition Mechanism of HFC-13.a by Experimental and DFT Method

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Journal of Thermal Science 2024年第5期33卷 1990-2003页

作者： XU Yunting ZHANG kai DAI Xiaoye SHI Lin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

In response to the Kigali Amendment to the Montreal Protocol and global low-carbon emission environmental requirements,the phase-out and decomposition of numerous HFC refrigerants have become urgent,necessitating efficient and mild decomposition *** study investigates the thermal decomposition and oxidative thermal decomposition pathways of the typical hydrofluorocarbon refrigerant HFC-13.a,employing a combination of experimental and quantum chemical DFT simulation *** chemical simulations reveal that the initial reaction bond cleavage serves as the rate-determining step during the thermal decomposition process,with the most easily detectable closed-shell products including CF_(2)=CHF,HF,CH_(3.F,CHF_(3.,CH_(2)F_(2),and CF_(4).Reactive oxygen species can significantly reduce the Gibbs free energy barrier for HFC-13.a *** achieve efficient degradation of HFC-13.a,appropriate catalysts should be developed and selected to increase the level of reactive oxygen species in the reaction *** studies further corroborate that HFC-13.a may undergo degradation through distinct reaction pathways under varying temperature(240℃to3.0℃)and pressure(0.1 MPa to 4.5 MPa)conditions,in agreement with simulation predictions.

关键词： HFC-13.a pyrolysis oxidative thermal decomposition DFT refrigerant

Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

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Nano Research 2024年第6期17卷 4825-4833页

作者： kai-kai Niu Chao-Qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng Yu Ling-Bao Xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

Collaborative Charging Scheduling in Wireless Charging Sensor Networks

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Computers, Materials & Continua 2024年第4期79卷 1613-1630页

作者： Qiuyang Wang zhen Xu Lei Yang School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan430048China

Wireless sensor networks (WSNs) have the trouble of limited battery power, and wireless charging provides apromising solution to this problem, which is not easily affected by the external environment. In this paper, we studythe recharging of sensors in wireless rechargeable sensor networks (WRSNs) by scheduling two mobile chargers(MCs) to collaboratively charge sensors. We first formulate a novel sensor charging scheduling problem with theobjective of maximizing the number of surviving sensors, and further propose a collaborative charging schedulingalgorithm(CCSA) for WRSNs. In the scheme, the sensors are divided into important sensors and ordinary *** can adaptively collaboratively charge the sensors based on the energy limit ofMCs and the energy demandof sensors. Finally, we conducted comparative simulations. The simulation results show that the proposed algorithmcan effectively reduce the death rate of the sensor. The proposed algorithm provides a solution to the uncertaintyof node charging tasks and the collaborative challenges posed by multiple MCs in practical scenarios.

关键词： Wireless rechargeable sensor network mobile charger collaborative charging adaptive charging

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： Xue-Qin Li Lu-kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Fluorinated semi-interpenetrating polymer networks for enhancing the mechanical performance and storage stability of polymer-bonded explosives by controlling curing and phase separation rates

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Defence Technology（防务技术） 2024年第8期38卷 58-66页

作者： Chao Deng Huihui Liu Yongping Bai zhen Hu School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150000China Wuxi HIT New Material Research Institute Co. Ltd.Wuxi 214000China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Herein, the effect of fluoropolymer binders on the properties of polymer-bonded explosives(PBXs) was comprehensively investigated. To this end, fluorinated semi-interpenetrating polymer networks(semiIPNs) were prepared using different catalyst amounts(denoted as F23.CLF-3.-D). The involved curing and phase separation processes were monitored using Fourier-transform infrared spectroscopy, differential scanning calorimetry, a haze meter and a rheometer. Curing rate constant and activation energy were calculated using a theoretical model and numerical method, respectively. Results revealed that owing to its co-continuous micro-phase separation structure, the F23.CLF-3.-D3.semi-IPN exhibited considerably higher tensile strength and elongation at break than pure fluororubber F23.4 and the F23.CLF-3.-D0 semi-IPN because the phase separation and curing rates matched in the initial stage of *** arc Brazilian test revealed that F23.CLF-3.-D-based composites used as mock materials for PBXs exhibited excellent mechanical performance and storage stability. Thus, the matched curing and phase separation rates play a crucial role during the fabrication of high-performance semi-IPNs;these factors can be feasibly controlled using an appropriate catalyst amount.

关键词： Semi-interpenetrating polymer networks Fluoropolymer Curing rate Phase separation rate Polymer-bonded explosives