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Reinforcement of High Impact Polystyrene by Aramid Nanoparticle Fillers Prepared via an In situ Bottom-up Approach

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Chinese Journal of Polymer Science 2024年第8期42卷 1167-1176页

作者： Xiang-jun Gong Zhi-Ping Zhao Chang-Mei Sun Ying Zhang Rong-jun Qu Ying Wang School of Chemistry and Materials Science Ludong UniversityYantai 264025China

In this work,aramid nanoparticles(ANPs)were prepared in dimethyl formamide(DMF)solution containing high impact polystyrene(HIPS)via a bottom-up *** electron microscopy(TEM)images showed that the obtained ANPs were evenly distributed in the HIPS matrix without any *** composition of the ANPs,i.e.,poly(p-phenyl-p-phenylenediamine)(PPTA),was confirmed by Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and X-ray diffractometer(XRD).The ANP/HIPS composites,obtained after ethanol precipitation,were added to neat HIPS as fillers to fabricate ANP/HIPS composite *** surface roughness and the glass transition temperature(T_g)of the sheets were characterized by atomic force microscope(AFM)and differential scanning calorimetry(DSC),*** with neat HIPS,the mechanical properties of the composite sheet were significantly improved,and the Young's modulus increased from 246.55 MPa to 2025.12 MPa,the tensile strength increased from 3.07 MPa to 29.76 MPa,and the toughness increased from 0.32 N/mm^2 to 3.92 N/mm^2,with an increase rate of 721%,869%and 1125%,***,the thermal stability of the composites improved with the increase in ANP content.

关键词： High impact polystyrene PPTA nanoparticle Reinforce Mechanical property

Interpretation of Chinese Expert Consensus on the Diagnosis and Management Strategy of Patients with Statin Intolerance: A guiding file for helping to lipid management for Chinese population

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Journal of Geriatric Cardiology 2024年第7期21卷 713-715页

作者： Jian-jun LI Cardiometabolic Center National Center for Cardiovascular DiseaseChinese Academy of Medical ScienceFuwai HospitalBeijingChina

It is well-known that elevated low-density lipoprotein cholesterol(LDL-C)is a causal risk factor for atheroscler-otic cardiovascular disease(ASCVD),statins are cornerstone drugs for the cause-based treatment of ASCVD,which has created a new era for ASCVD ***,statin intolerance is not clinically uncommon,which there are several issues with confu-sion and ***,a file named Chinese Expert Consensus on the Diagnosis and Management Strategy of Pa-tients With Statin Intolerance,like a navigator,has recently been published written by a team of experts from the Cardiovascular Metabolic Medicine Professional Committee,Expert Committee of the National Center for Cardiovascular Diseases aiming to en-hance the standardized clinical application of statins and improve the prevention and clinical *** this article,author briefly summarized the key points of above consensus in order to helping to comprehending the content of the consensus sugges-tions.

关键词： Expert Strategy corners

First Digit Distributions of Gamma-Ray Bursts

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Research in Astronomy and Astrophysics 2024年第5期24卷 70-75页

作者： Hou-Yu Lai jun-Jie Wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

The occurrence of the first significant digits from real world sources is usually not equally distributed,but is consistent with a logarithmic distribution instead,known as Benford’s *** this work,we perform a comprehensive investigation on the first digit distributions of the duration,fluence,and energy flux of gamma-ray bursts (GRBs) for the first *** a complete GRB sample detected by the Fermi satellite,we find that the first digits of the duration and fluence adhere to Benford’s ***,the energy flux shows a significant departure from this law,which may be due to the fact that a considerable part of the energy flux measurements is restricted by lack of spectral *** on the conventional duration classification scheme,we also check if the durations and fluences of long and short GRBs (with duration T_(90)>2 s and T_(90)≤2 s,respectively) obey Benford’s *** find that the fluences of both long and short GRBs still agree with the Benford distribution,but their durations do not follow Benford’s *** results hint that the long–short GRB classification scheme does not directly represent the intrinsic physical classification scheme.

关键词： (stars:)gamma-ray burst general-methods statistical-astronomical databases miscellaneous

Supermassive Primordial Black Holes for Nano-Hertz Gravitational Waves and High-redshift JWST Galaxies

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Research in Astronomy and Astrophysics 2024年第9期24卷 1-6页

作者： Hai-Long Huang Yong Cai jun-Qian Jiang jun Zhang Yun-Song Piao School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institute for Astrophysics School of PhysicsZhengzhou UniversityZhengzhou 450001China International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100190China Taiji Laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China

Recently,observational hints for supermassive black holes have been accumulating,prompting the question:Can primordial black holes(PBHs)be supermassive,particularly with masses M■10^(9)M_(⊙)?A supercritical bubble,containing an inflating baby universe,that nucleated during inflation can evolve into a PBH in our observable *** find that when the inflaton slowly transitions past a neighboring vacuum,the nucleation rate of supercritical bubbles inevitably peaks,leading to a mass distribution of multiverse PBHs with a peak mass up to M■10^(11)M_(⊙).Thus,our mechanism naturally provides a primordial origin for supermassive black holes.

关键词： (cosmology:)early universe (cosmology:)inflation (galaxies:)quasars:supermassive black holes

Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： En-wen ZHU Zi-wei DENG Han-jun ZHANG jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV *** first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant *** semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

Insights into photocatalytic mechanism over a novel Cu_(2)WS_(4)/MoS_(2) S-scheme heterojunction

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Rare Metals 2024年第7期43卷 3118-3133页

作者： Wei Zhao Ji-Hui Cao jun-Jie Liao Yun Liu Xiao-jun Zeng jun-Yu Shen Xue-Kun Hong Yang Guo He-Hua Zeng Ya-Zi Liu School of Materials Engineering Jiangsu Key Laboratory of Advanced Functional MaterialsSchool of Electronic and Information EngineeringChangshu Institute of TechnologyChangshu215500China School of Chemistry and Chemical Engineering Changji UniversityChangji 831100China State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control Ministry of Ecology and EnvironmentNanjing Institute of Environmental SciencesNanjing 210023China School of Environment Jiangsu Engineering Lab of Water and Soil Eco-RemediationNanjing Normal UniversityNanjing 210023China Department of Chemical Engineering Curtin UniversityPerthWA6845Australia

A novel efficient Cu_(2)WS_(4)/MoS_(2) step-scheme(S-scheme)heterojunction photocatalyst was constructed for the first time and applied in the removal of environmental *** the as-prepared photocatalysts,the Cu_(2)WS_(4)/MoS_(2)-8%heterojunc tion photoc atalyst demonstrates the optimal photocatalytic performance,with the catalytic oxidation efficiency of tetracycline(TC)and the catalytic reduction efficiency of Cr^(6+)reaching 93.3%and 82.1%,*** excellent catalytic properties of Cu_(2)WS_(4)/MoS_(2) heterojunction photocatalysts are attributed to the effective separation pathways of charges and the presence of S-scheme heterojunctions,together with stronger redox *** is speculated that the photogenerated carrier migration path of the Cu_(2)WS_(4)/MoS_(2) catalyst follows the typical S-scheme photocatalytic mechanism,which is verified by the in-depth experimental study and simulated calculations including the electron paramagnetic resonance(EPR)analysis,free radical quenching experiments,charge density distribution,and simulated built-in electric field formation at the interface,which acts as driving force to promote the separation of photoinduced electrons and ***,the photocatalytic mechanism of S-scheme photogenerated carrier migration for the Cu_(2)WS_(4)/MoS_(2) catalyst is revealed based on the systematic experimental techniques and simulated calculations,accounting for its superior photocatalytic oxidation and reduction *** study provides inspiring implications to develop high-efficient S-scheme photocatalytic systems for versatile applications in solarenergy conversion.

关键词： Cu_(2)WS_(4)/MoS_(2) S-scheme Heterojunction Photocatalysis

Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

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Tsinghua Science and Technology 2024年第1期29卷 216-231页

作者： Lilong Duan Wei Xue jun Huang Xiao Zheng School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

The problem of imbalanced data classification learning has received much *** classification algorithms are susceptible to data skew to favor majority samples and ignore minority *** weighted minority oversampling technique(MWMOTE)is an effective approach to solve this problem,however,it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority *** this end,we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering(SPMSC)to solve these ***,in order to effectively eliminate the effect of noisy samples,SPMsC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority *** that MWMOTE may generate duplicate samples,we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate ***,data cleaning is performed on the processed data to further eliminate class *** on extensive benchmark datasets demonstrate the effectiveness of SPMsC compared with other sampling methods.

关键词： imbalanced data classification oversampling noise filtering clustering

Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu LI Kaiyuan ZHANG Zhigang LI jun LI Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall

Two simple memristive maps with adaptive energy regulation and digital signal process verification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 382-394页

作者： Feifei YANG Lujie REN jun MA Zhigang ZHU College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China School of Information Science and Engineering Dalian Polytechnic UniversityDalian 116034China

Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy *** involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive *** this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural *** corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear *** Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive *** Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and *** two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these *** scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.

关键词： Hamilton energy Discrete memristor Self-adaptive regulation Digital signal process(DSP)implementation