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The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： Zhi-Chu Ma Rui Niu wen Zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

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Brillouin expanded time-domain analysis based on dual optical frequency combs

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Light(Science & Applications) 2024年第8期13卷 1534-1544页

作者： Jae Hyeong Youn kwang Yong Song Sonia Martin-Lopez Miguel Gonzalez-Herraez María R.Fernández-Ruiz Dept.of Physics Chung-Ang UniversitySeoulKorea Dept.of Electronics Universidad de AlcaláMadridSpain

Brillouin Optical Time-Domain Analysis(BOTDA)is a widely-used distributed optical fiber sensing technology employing pulse-modulated pump waves for local information retrieval of the Brillouin gain or loss *** spatial resolution of BOTDA systems is intrinsically linked to pulse duration,so high-resolution measurements demand high electronic bandwidths inversely proportional to the *** paper introduces Brillouin Expanded Time-Domain Analysis(BETDA)as a modified BOTDA system,simultaneously achieving high spatial resolution and low detection *** two optical frequency combs(OFCs)with different frequency intervals as pump and probe,local Brillouin gain spectra are recorded by their spectral beating traces in an expanded time domain.A 2-cm-long hotspot located in a 230m single-mode fiber is successfully measured in the time domain with a detection bandwidth of less than 100 kHz using dual OFCs with tailored spectral phase,line spacing,and bandwidth.

关键词： pump optical fiber

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Influence of laser parameters on the microstructures and surface properties in laser surface modification of biomedical magnesium alloys

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Journal of Magnesium and Alloys 2024年第1期12卷 72-97页

作者： Chee Ying Tan Cuie wen Hua Qian Ang School of Engineering RMIT UniversityMelbourneVictoria 3001Australia

Biodegradable implants from magnesium(Mg)alloys have emerged in the biomedical field especially in the orthopedic and cardiovascular stent applications owing to their low density,high specific strength,excellent machinability,good biocompatibility,and *** primary shortcoming of Mg-based implants is their low corrosion resistance in the physiological environment,which results in premature mechanical integrity loss before adequate healing and the production of excessive hydrogen gas,which is harmful to the body tissues and negatively affects the biocompatibility of the *** surface modification has recently received attention because it can improve the surface properties such as surface chemistry,roughness,topography,corrosion resistance,wear resistance,hydrophilicity,and thus cell response to the surface of the *** composition and microstructures including textures and phases of laser-treated surfaces depend largely on the laser processing parameters(input laser power,laser scan velocity,frequency,pulse duration,pressure,gas circulation,working time,spot size,beam focal position,and laser track overlap)and the thermophysical properties of the substrate(solubility,melting point,and boiling point).This review investigates the impacts of various laser surface modification techniques including laser surface melting,laser surface alloying,laser cladding,laser surface texturing,and laser shock peening,and highlights their significance in improving the surface properties of biodegradable Mg alloys for implant ***,we explore how different laser process parameters affect its composition,microstructure,and surface properties in each laser surface modification technique.

关键词： Biocompatibility Biodegradability Corrosion Implant applications Laser surface modification Magnesium alloys

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Multifunctional carbon materials from rugose rose for energy storage and water purification

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FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING 2024年第9期18卷 97-0页

作者： Li, Peng-Hui Zhou, Hui Wu, wen-Juan Nanjing Forestry Univ Jiangsu Coinnovat Ctr Efficient Proc & Utilizat Fo Nanjing 210037 Peoples R China Nanjing Forestry Univ Coll Light Ind & Food Engn Nanjing 210037 Peoples R China East China Univ Sci & Technol Coll Chem Engn Shanghai 200237 Peoples R China State Key Lab Chem Engn Shanghai 200237 Peoples R China

With the advancement of social process, the resource problem is becoming more prominent, biomass materials come into being, and it is becoming more and more important to explore and prepare efficient and multifunctional biomass materials to alleviate the problems of energy storage and water pollution. In this paper, nitrogen-doped hierarchical porous carbon materials (NRRC) were produced by one-step carbonization of withered rose as raw material and melamine as nitrogen source with KOH-activated porosification. The resulting nitrogen-doped porous carbon material had the most abundant pores and the best microspherical graded pore structure, with a specific surface area of up to 1393 m2g-1, a pore volume of 0.68 cm3g-1, and a nitrogen-doped content of 5.52%. Electrochemical tests showed that the maximum specific capacitance of NRRC in the three-electrode system was 346.4 Fg-1 (0.5 Ag-1), which was combined with favorable capacitance retention performance and cycling stability. The NRRC//NRRC symmetric supercapacitors were further assembled, and the maximum energy density of a single device was 23.88 Whkg-1, which still maintains excellent capacitance retention and cyclic charging/discharging stability. For example, the capacitance retention rate was always close to 96.27% with almost negligible capacitance loss after 10000 consecutive charge/discharge cycles (current density: 10 Ag-1). Regardless of the three-electrode or two-electrode system, the super capacitive performance of NRRC porous carbon materials was comparable to the electrochemical performance of many reported biomass porous carbon materials, which showed better energy storage advantages and practical application potential. In addition, NRRC porous carbon materials had excellent water purification ability. The dye adsorption test confirmed that NRRC had a high adsorption capacity (491.47 mgg-1) for methylene blue. This und

关键词： rose carbon adsorption electrode material electrochemical performance POROUS CARBON SUPERIOR PERFORMANCE ACTIVATED CARBON SURFACE-AREA SUPERCAPACITOR BIOMASS ADSORPTION ELECTRODE NITROGEN

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Energy-based Directional Pilot Protection for Distribution Networks with IBDGs Considering Unmeasured Load Switching

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 139-150页

作者： Chenghan Zhou Guibin Zou Shuo Zhang Xuhui wen Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250061China

Inverter-based distributed generations(IBDGs)are the main approach to utilizing clean energy in distribution networks(DNs).Compared with synchronous source,fault response of IBDG is very *** a result,in DNs with high penetration of IBDGs,legacy protection schemes will no longer be *** this paper,an energy-based directional pilot protection scheme suitabie for DNs with IBDGs is *** scheme considers the large range of phase angle caused by IBDG integration and uses improved energy polarity criterion to determine fault *** addition,magnitude of energy is used to distinguish between faults and load switching to overcome maloperation of directional pilot protection caused by internal unmeasured load *** proposed scheme first uses local measured information to determine fault direction sign and then exchanges the direction sign with the remote *** scheme does not require high-bandwidth communication and strict data synchronization,so it can be implemented at a low ***,simulation studies verify effectiveness of the proposed scheme.

关键词： Distribution network energy polarity inverterbased distributed generation pilot protection unmeasured load

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Spatially Coupled Codes via Bidirectional Block Markov Superposition Transmission

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Tsinghua Science and Technology 2024年第3期29卷 656-670页

作者： Gaoyan Li Shancheng Zhao Haiqiang Chen Jinming wen College of Information Science and Technology Jinan UniversityGuangzhou 510632China Guangxi Key Laboratory of Multimedia Communications and Network Technology Guangxi UniversityNanning 530004China

In this paper,we present a new class of spatially coupled codes obtained by using both non-recursive and recursive block-oriented *** resulting codes are termed as bidirectional block Markov superposition transmission(BiBMST)***,we perform an iterative decoding threshold analysis according to protograph-based extrinsic information transfer(PEXIT)charts for the BiBMST codes over the binary erasure channels(BECs).Secondly,we derive the generator and parity-check matrices of the BiBMST ***,extensive numerical results are presented to show the advantages of the proposed BiBMST ***,our numerical results show that,under the constraint of an equal decoding latency,the BiBMST codes perform better than the recursive BMST(rBMST)***,the simulation results show that,in finite-length regime,negligible performance gain is obtained by increasing the encoding *** solve this limitation by introducing partial superposition,and the resulting codes are termed as partially-connected BiBMST(PC-BiBMST)*** results have confirmed the advantages of the PC-BiBMST codes over the original BiBMST *** also present extensive simulation results to show the performance advantages of the PC-BiBMST codes over the spatially coupled low-density parity-check(SC-LDPC)codes,spatially coupled generalized LDPC(SC-GLDPC)codes,and the original BiBMST codes in the finite-length regime.

关键词： block Markov superposition transmission(BMST) protograph-based extrinsic information transfer(PEXIT) capacity-approaching codes spatial coupling

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Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： Chao-Yue Sun wen Li Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

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N-glycan biosignatures as a potential diagnostic biomarker for earlystage pancreatic cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 659-669页

作者： Yan-Rong wen Xia-wen Lin Yu-wen Zhou Lei Xu Jun-Li Zhang Cui-Ying Chen Jian He Department of Nuclear Medicine Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina Department of Research and Development Sysdiagno(Nanjing)Biotech Co.LtdNanjing 210008Jiangsu ProvinceChina

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)has a poor prognosis,with a 5-year survival rate of less than 10%,owing to its late-stage *** detection of pancreatic cancer(PC)can significantly increase survival *** To identify the serum biomarker signatures associated with early-stage PDAC by serum N-glycan *** An extensive patient cohort was used to determine a biomarker signature,in-cluding patients with PDAC that was well-defined at an early stage(stages I and II).The biomarker signature was derived from a case-control study using a case-cohort design consisting of 29 patients with stage I,22 with stage II,4 with stage III,16 with stage IV PDAC,and 88 *** used multiparametric analysis to identify early-stage PDAC N-glycan signatures and developed an N-glycan sig-nature-based diagnosis model called the“Glyco-model”.RESULTS The biomarker signature was created to discriminate samples derived from patients with PC from those of controls,with a receiver operating characteristic area under the curve of *** addition,the biomarker signature combined with cancer antigen 19-9 could discriminate patients with PDAC from controls,with a receiver operating characteristic area under the curve of ***-model demonstrated favorable diagnostic performance in all stages of *** diagnostic sensitivity for stage I PDAC was 89.66%.Core Tip:This study employed a patient cohort to investigate the N-glycan signature of early-stage pancreatic cancer(PC).Serum N-glycans analysis was conducted to identify the serum biomarker signature associated with early-stage pancreatic ductal adenocarcinoma(PDAC),resulting in the identification of nine early-stage PDAC N-glycan ***,utilizing these biosignatures,a diagnostic model named the“Glyco-model”was developed,demonstrating promising diagnostic performance across all stages of *** study revealed that the diagnostic sensitivity for stage I PDAC was determined to be 89.66%.Co

关键词： Glycomics N-glycans Biomarkers Pancreatic cancer Predictive modeling

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A Distortion Self-Calibration Method for Binocular High Dynamic Light Adjusting and Imaging System Based on Digital Micromirror Device

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2036-2038页

作者： Pei Wu Yanjie Wang Honghai Sun Zhuoman wen University of Chinese Academy of Sciences Beijing 100049and NIO Inc.Shanghai 200000China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical design of the system, the causes of the distortion are given and a distortion model is established. Then, a quick and accurate self-calibration method is designed. The experiments indicate that the method can calibrate the two image sensors of the system at the same time,the average pixel deviation of the calibrated system is less than 0.5pixels and the maximum deviation is less than 1 pixel.

关键词： Dynamic system deviation

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Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-Li Wang wen-Jun Huang De-Li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： Deep well Casing integrity Casing wear Casing corrosion Burst strength

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