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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han zhu Xiong Zhang Xiao-Qiang Li Peng Li yan-Bin Wang Shuang Zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

Experimental Study on Soot Suppression of Acetylene Diffusion Flame by Acoustic-Excited Oscillation in Rijke-Type Burner

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Journal of Thermal Science 2024年第1期33卷 235-248页

作者： zhu Yibin GUO Hui SUO yan'ge WU Minle YE yanghui LI Guoneng ZHANG Zhiguo School of Mechanical and Energy Engineering Zhejiang University of Science and TechnologyHangzhou 310023China

This work reports that the flame oscillation induced by acoustic excitation can effectively suppress soot generation in Rijke-type *** the acoustic frequency is close to the natural frequency of the burner system,it can produce resonance resulting in intense oscillation of the *** relationship between the soot suppression efficiency and the acoustic field of standing wave at different flame positions is *** with that under self-excited oscillation,when there is external forced acoustic force introduced to the flame,oscillation combustion occurred in a lager zone in the glass *** fundamental cause of different soot suppression efficiency at different positions is that the standing wave acoustic field causes the particles to move at different speeds in different positions of the glass *** axial particle velocity difference results in the formation of acoustic vortexes and the change of the flame *** high particle velocity causes the air in the glass tube to turn into the turbulent condition and make the flame temperature *** results show that the surface growth rate of soot is reduced,while the oxidation rate of soot is enhanced,which result in the soot suppression under acoustic *** study can provide some reference for the practical application of oscillate combustion in soot suppression.

关键词： soot suppression acetylene diffusion flame acoustic-excited oscillation standing wave

One-step hydrothermal synthesis of few-layered metallic phase MoS2 for high-performance supercapacitors

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Progress in Natural Science:Materials International 2024年第2期34卷 429-436页

作者： Jing Xu Xulong Yuan Yujie Zhao Shaoqi Rui Qingling Jia Han Li Shun Lu bing Li Yongxing Zhang Xuebin zhu Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation Anhui Province Key Laboratory of Intelligent Computing and Applications Anhui Province Industrial Generic Technology Research Center for Alumics Materials Huaibei Normal University Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Key Laboratory of Materials Physics Institute of Solid State Physics HFIPS Chinese Academy of Sciences

In recent years,molybdenum disulfide（MoS2） has gained significant attention in the scientific *** MoS2demonstrates unique properties and potential ***,the synthesis of few-layered and high-purity 1T-MoS2is still a *** this study,we successfully employed a hydrothermal method to synthesize few-layered and high-purity *** purity of the material is controlled by a combination of sodium borohydride and ***,the few-layered 1T-MoS2exhibits exceptional performance as a supercapacitor,including the high specific capacitance(250.3 F g-1at a current density of 1 A g-1) and excellent long-trem cycling stability（90.7 % after 5000 cycles）.Meanwhile,the asymmetric device assembled by 6-FL-1TMoS2and active carbon on carbon cloths exhibits excellent flexibility and high energy and power density(23.1μWh cm-2at 600 μW cm-2,55 μWh cm-2at 12000 μW cm-2).This work provides valuable insights into the synthesis of few-layered and high-purity 1T-MoS2,opening up new avenues for further research and applications.

关键词： 1T-MoS2 Few-layered High-purity One-pot hydrothermal method Supercapacitor

Modeling and analysis of gradient metamaterials for broad fusion bandgaps

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1155-1170页

作者： Changqi CAI Chenjie zhu Fengyi ZHANG Jiaojiao SUN Kai WANG Bo yan Jiaxi ZHOU School of Mechanical Engineering Zhejiang Sci-Tech University School of Material and Environmental Engineering Hangzhou Dianzi University College of Mechanical and Vehicle Engineering Hunan University

A gradient metamaterial with varying-stiffness local resonators is proposed to open the multiple bandgaps and further form a broad fusion bandgap. First, three local resonators with linearly increasing stiffness are periodically attached to the spring-mass chain to construct the gradient metamaterial. The dispersion relation is then derived based on Bloch's theorem to reveal the fusion bandgap theoretically. The dynamic characteristic of the finite spring-mass chain is investigated to validate the fusion of multiple bandgaps. Finally, the effects of the design parameters on multiple bandgaps are discussed. The results show that the metamaterial with a non-uniform stiffness gradient pattern is capable of opening a broad fusion bandgap and effectively attenuating the longitudinal waves within a broad frequency region.

关键词： local resonance mechanism elastic metamaterial stiffness gradient bandgap fusion broadband wave attenuation O321 74H45 74J05

High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao Lu-Kun Feng Hui Xie Ming-Liang Wang bing Guo Zhi-Yong Xue Cai-Zhen zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

The Application of Solid Waste in Thermal Insulation Materials: A Review

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Journal of Renewable Materials 2024年第2期12卷 329-347页

作者： Ming Liu Pinghua zhu Xiancui yan Haichao Li Xintong Chen School of Environmental Science and Engineering Changzhou UniversityChangzhou213164China School of Urban Construction Changzhou UniversityChangzhou213164China

As socioeconomic development continues,the issue of building energy consumption has attracted significant attention,and improving the thermal insulation performance of buildings has become a crucial strategic ***,the application of solid waste in insulation materials has also become a hot *** paper reviews the sources and classifications of solid waste,focusing on research progress in its application as insulation materials in the domains of daily life,agriculture,and *** research shows that incorporating household solid waste materials,such as waste glass,paper,and clothing scraps into cementitious thermal insulation can significantly reduce the thermal conductivity of the materials,leading to excellent thermal insulation *** materials prepared from agricultural solid waste,such as barley straw,corn stalk,chicken feather,and date palm fibers,possess characteristics of lightweight and strong thermal *** solid waste,including waste tires,iron tailings,and coal bottom ash,can also be utilized in the preparation of insulation *** innovative applications not only have positive environmental significance by reducing waste emissions and resource consumption,but also provide efficient and sustainable insulation solutions for the construction ***,to further optimize the mix design and enhance the durability of insulation materials,continuous research is required to investigate the mechanisms through which solid waste impacts the performance of insulation materials.

关键词： Solid waste building energy consumption insulation material sustainability

Design of artificial biomimetic channels with Na+permeation rate and selectivity potentially outperforming the natural sodium channel

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Nano Research 2024年第9期17卷 8638-8646页

作者： Zhi zhu yan Zhao Chao Chang Shaojian yan Tingyu Sun Shiyu Gu yangmei Li Dengsong Zhang Chunlei Wang Xiao Cheng Zeng School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Innovation Laboratory of Terahertz Biophysics National Innovation Institute of Defense TechnologyBeijing 100071China School of Physics Peking UniversityBeijing 100871China International Joint Laboratory of Catalytic Chemistry College of SciencesShanghai UniversityShanghai 200444China Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

Artificial ion channels that enable high-efficiency ion transport have important implications in nanofluidics and biomedical applications such as drug ***,we show a simulation-based chemical design of a biomimetic sodium channel that possesses permeation rate and selectivity potentially higher than those of the state-of-the-art natural vertebrate voltage-gated sodium ***,our theoretical findings have undergone empirical testing,aligning well with the Arrhenius law as derived from a diverse range of experimental *** high-efficiency ion transport is achieved by anchoring the carboxylate functional groups within the channel filter.A key chemical guiding principle underlying the ion channel design is that the free-energy barrier for the Na+passage across the channel should be comparable to typical thermal energy at room *** the implementation of the chemical design,we found that the relatively low free-energy barrier can be attributed to the compensation effect of the carboxylate groups to the partially lost oxygen shell of the ion within the ion channel,as well as to the consonant vibration of the ions inside and outside the *** mechanistic understanding brings new insight,at the molecular level,into the high-efficiency ion transport across the designed membrane *** proof of principle achieved from the simulations will stimulate future experimental confirmation and potential applications of the high-performance artificial channels in nanofluidics and in bioinspired iontronics.

关键词： sodium channels anchoring carboxylate functional groups molecular dynamics simulations low free-energy barrier for ion passage thermal kinetic energy

Increased retinal venule diameter as a prognostic indicator for recurrent cerebrovascular events:a prospective observational study

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Neural Regeneration Research 2024年第5期19卷 1156-1160页

作者： Ying Zhao Dawei Dong Ding yan bing yang Weirong Gui Man Ke Anding Xu Zefeng Tan Department of Neurology and Stroke Center the First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina Clinical Neuroscience Institute the First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina Department of Neurology the First People’s Hospital of FoshanFoshanGuangdong ProvinceChina

Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy ***,the ability of retinal vasculature changes,specifically focusing on retinal vessel diameter,to predict the recurrence of cerebrovascular events in patients with ischemic stroke has not been determined *** previous studies have shown a link between retinal vessel diameter and recurrent cerebrovascular events,they have not incorporated this information into a predictive ***,this study aimed to investigate the relationship between retinal vessel diameter and subsequent cerebrovascular events in patients with acute ischemic ***,we sought to establish a predictive model by combining retinal veessel diameter with traditional risk *** performed a prospective observational study of 141 patients with acute ischemic stroke who were admitted to the First Affiliated Hospital of Jinan *** of these patients underwent digital retinal imaging within 72 hours of admission and were followed up for 3 *** found that,after adjusting for related risk factors,patients with acute ischemic stroke with mean arteriolar diameter within 0.5-1.0 disc diameters of the disc margin(MAD_(0.5-1.0DD))of≥74.14μm and mean venular diameter within 0.5-1.0 disc diameters of the disc margin(MVD_(0.5-1.0DD))of≥83.91μm tended to experience recurrent cerebrovascular *** established three multivariate Cox proportional hazard regression models:model 1 included traditional risk factors,model 2 added MAD_(0.5-1.0DD)to model 1,and model 3 added MVD0.5-1.0DD to model *** 3 had the greatest potential to predict subsequent cerebrovascular events,followed by model 2,and finally model *** findings indicate that combining retinal venular or arteriolar diameter with traditional risk factors could improve the prediction of recurrent cerebrovascular events in patients with acute ischemic stroke,and that retinal imaging c

关键词： acute ischemic stroke arteriolar cerebrovascular events diameter digital retinal imaging microvasculature prediction recurrent retina venular

Firebird sirolimus eluting stent versus bare mental stent in patients with ST-segment elevation myocardial infarction

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Chinese Medical Journal 2007年第10期120卷 863-867页

作者： GAO Hai yan Hong-bing zhu Xiao-ling LI Nan AI Hui WANG Jian LI Shi-ying yanG Duo Emergency Center for Heart Lung and Vessel Diseases Beijing Anzhen Hospital of Capital University of Medical Sciences Beijing 100029 China

Background There are few evidences about the value of drug eluting stent in patients with ST-segment elevation myocardial infarction （STEMI）. We prospectively designed a randomized controlled trial to compare the safety and efficacy of Firebird sirolimus eluting stent （Firebird stent） and bare metal stent （BMS）. Methods Patients with STEMI enrolled during one year period were randomized to undergo implantation of Firebird stent or BMS, and clinical and angiographic follow-up. The primary endpoint of the present study was in-lesion late lumen loss （LLL） at 6 months, and secondary endpoint includes stent thrombosis and major adverse cardiac events （MACE） at 6 months. Results During one year period, 156 patients were randomized into the Firebird stent group （101 patients with an average age of 57.8 years） or the BMS group （55 patients with 59.7 years on average）. Six-month angiographic follow-up was available in 66.3% and 63.7% of patients assigned to Firebird stent and BMS, respectively. At 6-month follow-up, mortality, target vessel revascularization （TVR） and MACE were 2.0%, 6.9% and 9.9% in the Firebird stent group, while 3.6%, 30.9% and 36.4% in the BMS group （P〈0.05）. Subacute thrombosis occurred in 1 patient in both groups, respectively. The mean LLL was 0.18 mm in the Firebird stent group versus 0.72 mm in the BMS group. Conclusion Implantation of Firebird sirolimus eluting stent for STEMI may greatly reduce TVR and MACE at 6 months with low incidence of acute/subacute stent thrombosis compared with BMS.

关键词： myocardial infarction drugs stents

Experimental Study on Vortex-Induced Vibration of Rough Risers with Coupling Interference Effect Under Side-by-Side Arrangement

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China Ocean Engineering 2024年第1期38卷 18-28页

作者： HU Ze-bo LIU Zhen LI Peng GUO Hai-yan WANG Shu-bing REN Xiao-hui HOU Hao WANG Ye-shuo College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China CHEC Dredging Co. LtdShanghai 200136China

A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined *** roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the *** risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference *** experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency *** addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser.

关键词： marine riser vortex-induced vibration side-by-side arrangement roughness interference effect