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Journal of Environmental Sciences 2024年第6期140卷 91-102页

作者： Ruxian Hou Jiewen xiao Qian wu Tianyu Zhang Qiang Wang Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China

CO_(2)hydrogenation to methanol has become one of the most promising ways for CO_(2)utilization,however,the CO_(2)conversion rate and methanol selectivity of this reaction still need to be improved for industrial application.Here we investigated the structure-activity relationship for CO_(2)conversion to methanol of In_(2)O_(3)-based catalysts by modulating morphology and decorating Au.Three different Au/In_(2)O_(3)catalysts were prepared,their activity follow the sequence of Au/In_(2)O_(3)-nanosphere(Au/In_(2)O_(3)-NS)>Au/In_(2)O_(3)-nanoplate(Au/In_(2)O_(3)-NP)>Au/In_(2)O_(3)-hollow microsphere(Au/In_(2)O_(3)-HM).Au/In_(2)O_(3)-NS exhibited the best performance with good CO_(2)conversion of 12.7%,high methanol selectivity of 59.8%,and large space time yield of 0.32 g CH_(3)OH/(hr·gcat)at 300℃.The high performance of Au/In_(2)O_(3)-NS was considered as the presence of Au.It contributes to the creation of more surface oxygen vacancies,which further promoted the CO_(2)adsorption and facilitated CO_(2)activation to form the formate intermediates towards methanol.This work clearly suggests that the activity of In_(2)O_(3)catalyst can be effective enhanced by structure engineering and Au decorating.

关键词： CO_(2)hydrogenation Methanol Au/In_(2)O_(3) Morphology Oxygen vacancies

Statistical study of magnetic holes in the upstream region of Mercury’s bow shock

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Earth and Planetary Physics 2024年第2期8卷 326-337页

作者： GuoQiang Wang SuDong xiao MingYu wu YuanQiang Chen TieLong Zhang Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518055China Shenzhen Key Laboratory of Numerical Prediction for Space Storm Harbin Institute of TechnologyShenzhen 518055China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Space Research Institute Austrian Academy of SciencesGrazAustria

Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the properties of the magnetic holes with shorter durations are still unclear.Here,we investigate the magnetic holes with durations of 0.1-100 s in the upstream region of Mercury’s bow shock based on observations by the MESSENGER(MErcury Surface,Space ENvironment,GEochemistry,and Ranging)spacecraft.They can be divided into two groups according to the distribution of their duration:small-duration magnetic holes(SDMHs,0.6 s).The duration of each group approximately obeys a log-normal distribution with a median of~0.25 s and 3 s,respectively.Approximately 1.7%(32.6%)of the SDMHs(LDMHs)reduce the magnetic field strength by more than 50%.For both groups,some structures have a linear or quasi-linear polarization,whereas others have an elliptical polarization.The magnetic hole events in both groups tend to have a higher rate of occurrence when the interplanetary magnetic field strength is weaker.Their occurrence rates are also affected by Mercury’s foreshock,which can increase(decrease)the occurrence rate of the SDMHs(LDMHs).This finding suggests that Mercury’s foreshock might be one source of the SDMHs and that the foreshock can destroy some LDMHs.These observations suggest that a new group of magnetic holes with durations of<0.6 s exist in the upstream region of Mercury’s bow shock.

关键词： magnetic hole solar wind Mercury foreshock

A feedback control method for phase signal demodulation in fber-optic hydrophones

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 515-528页

作者： Zhiqiang LIU Lei XIA Qiangfeng LYU bin wu Ronghua HUAN Zhilong HUANG Department of Mechanics Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang UniversityHangzhou 310000China Huanjiang Laboratory Zhuji 311899Zhejiang ProvinceChina Advanced Technology Research Institute Zhejiang UniversityHangzhou 310000China

In the realm of acoustic signal detection,the identification of weak signals,particularly in the presence of negative signal-to-noise ratios,poses a significant challenge.This challenge is further heightened when signals are acquired through fiber-optic hydrophones,as these signals often lack physical significance and resist clear systematic modeling.Conventional processing methods,e.g.,low-pass filter(LPF),require a thorough understanding of the effective signal bandwidth for noise reduction,and may introduce undesirable time lags.This paper introduces an innovative feedback control method with dual Kalman filters for the demodulation of phase signals with noises in fiber-optic hydrophones.A mathematical model of the closed-loop system is established to guide the design of the feedback control,aiming to achieve a balance with the input phase signal.The dual Kalman filters are instrumental in mitigating the effects of signal noise,observation noise,and control execution noise,thereby enabling precise estimation for the input phase signals.The effectiveness of this feedback control method is demonstrated through examples,showcasing the restoration of low-noise signals,negative signal-to-noise ratio signals,and multi-frequency signals.This research contributes to the technical advancement of high-performance devices,including fiber-optic hydrophones and phase-locked amplifiers.

关键词： feedback control method fiber-optic hydrophone acoustic signal detection phase signal

Assessing the energy release characteristics during the middle detonation reaction stage of aluminized explosives

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Defence Technology（防务技术） 2024年第3期33卷 270-277页

作者： Kun Yang Lang Chen Danyang Liu bin Zhang Jianying Lu Junying wu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows significant differences.However,at present,there are few effective methods for evaluating the energy release characteristics of the middle reaction stage of such explosives,which can have a duration of tens to hundreds of microseconds.The present work demonstrates an approach to assessing the midstage of an aluminized explosive detonation based on a water push test employing a high degree of confinement.In this method,the explosive is contained in a steel cylinder having one end closed that is installed at the bottom of a transparent water tank.Upon detonation,the gaseous products expand in one direction while forcing water ahead of them.The resulting underwater shock wave and the interface between the gas phase products and the water are tracked using an ultra-high-speed framing and streak camera.The shock wave velocity in water and the expansion work performed by the gaseous detonation products were calculated to assess the energy release characteristics of aluminized explosives such as CL-20 and RDX in the middle stage of the detonation reaction.During the middle stage of the detonation process of these aluminized explosives,the aluminum reaction reduced the attenuation of shock waves and increased the work performed by gas phase products.A higher aluminum content increased the energy output while the presence of oxidants slowed the energy release rate.This work demonstrates an effective means of evaluating the performance of aluminized explosives.

关键词： Aluminized explosive Non-ideal detonation Water push test Energy release

Clinical efficacy and gene chip expression analysis of Shenzhu Guanxin recipe granules(参术冠心方颗粒) in patients with intermediate coronary lesions

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Journal of Traditional Chinese Medicine 2024年第3期44卷 545-553页

作者： JIN xiao wu bingxin LIN Miaoyang ZHONG Biying LIN Luoqi XU Danping Department of Traditional Chinese Medicine the First Affiliated Hospital of Jinan UniversityJinan University Department of Cardiology Second Clinical College of Guangzhou University of Chinese Medicine Department of Traditional Chinese Medicine the Eighth Affiliated HospitalSun Yat-Sen University

OBJECTIVE: To evaluate the clinical efficacy and safety of Shenzhu Guanxin recipe granules(参术冠心颗粒, SGR) in treating patients with intermediate coronary lesions(ICL), and to investigate the potential mechanism though a transcriptome sequencing approach. METHODS: ICL patients with Qi deficiency and phlegm stasis were adopted and randomly assigned to a case group or a control by random number generator in a 1∶1 randomization ratio to evaluate the clinical efficacy. RESULTS: There was no significant difference between the two groups in coronary computed tomography angiography related indexes in the two groups before and after intervention. Through the gene chip expression analysis, it is finally concluded that there are 355 differential mRNAs(190 up-regulated genes and 165 down regulated genes) when compared the SGR group and placebo group. Through protein-protein interaction network analysis of differentially expressed genes, 10 hub genes were finally obtained: CACNA2D2, CACNA2D3, DNAJC6, FGF12, SGSM2, CACNA1G, LRP6, KIF25, OXTR, UPB1. CONCLUSIONS: SGR combined with Western Medicine can be safely used to treat ICL patients with Qi deficiency and phlegm stasis. The possible mechanism of action and relevant gene loci and pathway were proposed.

关键词： Shenzhu Guanxin recipe granules deficiency and phlegm stasis gene expression profiling intermediate coronary lesions

The prognostic value of collateral circulation in coronary chronic total occlusion underwent percutaneous coronary intervention

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Journal of Geriatric Cardiology 2024年第2期21卷 232-241页

作者： xiao-Ying HU Wei-Xian YANG Chang-Dong GUAN Li-Hua XIE Ke-Fei DOU Yong-Jian wu Jin-Qing YUAN Jie QIAN Yue-Jin YANG Shu-bin QIAO Lei SONG Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina National Clinical Research Center for Cardiovascular Diseases BeijingChina Catheterization Laboratories Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

BACKGROUND The prognostic value of coronary collateral circulation(CC)in patients undergoing chronic total occlusion(CTO)percutaneous coronary intervention(PCI)is underdetermined.The purpose of the study was to assess the prognostic value of current two CC grading systems and their association with long-term outcomes in patients with CTO underwent PCI.METHODS We consecutively enrolled patients with single-vessel CTO underwent PCI between January 2010 and December2013.All patients were categorized into well-developed or poor-developed collaterals group according to angiographic Werner's CC(grade 2 vs.grade 0–1)or Rentrop(grade 3 vs.grade 0–2)grading system.The primary endpoint was 5-year cardiac death.RESULTS Of 2452 enrolled patients,the overall technical success rate was 74.1%.Well-developed collaterals were present in686 patients(28.0%)defined by Werner's CC grade 2,and in 1145 patients(46.7%)by Rentrop grade 3.According to Werner's CC grading system,patients with well-developed collaterals had a lower rate of 5-year cardiac death compared with those with poordeveloped collaterals(1.6%vs.3.3%,P=0.02),those with suboptimal recanalization was associated with higher rate of 5-year cardiac death compared with optimal recanalization(4.7%vs.0.8%,P=0.01)and failure patients(4.7%vs.1.6%,P=0.12).However,the similar effect was not shown in Rentrop grading system.CONCLUSIONS In patients with the single-vessel CTO underwent PCI,well-developed collaterals by Werner's CC definition were associated with lower rate of 5-year cardiac death.Werner's CC grading system had a greater prognostic value than Rentrop grading system in patients with CTO underwent PCI.

关键词： coronary collateral occlusion

Facile and effective synthesis strategy for terbium-doped hydroxyapatite toward photoelectric devices and flexible functional fibers

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Rare Metals 2024年第4期43卷 1713-1723页

作者： xiao-Dong Zhang Kun Nie Zi-Yao Hu Ran-Ran Zhou Xiu-Qiang Duan wu-bin Dai Song-Song Nie Song-Jun Yao Luo-Xin Wang Le-Fu Mei Hua Wang Yi-Yi Yao xiao-Xue Ma Key Laboratory for New Textile Materials and Applications and State Key Laboratory of New Textile Materials and Advanced Processing Technology School of Materials Science and EngineeringWuhan Textile University Key Laboratory of Testing and Tracing of Rare Earth Products for State Market Regulation Jiangxi University of Science and Technology Hubei Key Laboratory of Plasma Chemistry and Advanced Materials and Key Laboratory of Green Chemical Engineering Process of Ministry of Education Wuhan Institute of Technology Xiangyang Power Supply Company Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences (Beijing) Department of Chemistry and Biochemistry University of California Los Angeles

As a material with good biocompatibility,hydroxyapatite（HAP） can have optical properties after doping with various rare earth ions.As a biocompatible fluorescent material,doped HAP could have broad applications in biological probes,drug delivery,optoelectronic materials,fluorescence anti-counterfeiting,and other aspects.In this paper,we put forward the preparation of HAP doped with terbium（Ⅲ） ions(Tb3+) by hydrothermal co-precipitation.By controlling the Tb3+doping content in reaction and the reaction time,the changes in HAP's structure,morphology,and luminescence properties under different conditions were studied.When the doping amount of Tb3+reached an optimal value,the dipole-quadrupole would occur and the concentration would be quenched.The control experiment showed that the optimal Tb3+content was 7.5 × 10-5mol,which showed the best fluorescence performance.HAP,a non-luminous material,was rarely used in the field of fluorescent anti-counterfeiting and photoelectric devices.We proposed to prepare a luminescent aramid/polyphenylene sulfide（ACFs/PPS） fiber paper and a new light-emitting diode（LED） using the Tb-doped HAP phosphor.The composite sample exhibited an excellent stability and fluorescence performance,which also demonstrated a possibility of HAP applications in anticounterfeiting and photoelectric.The introduction of Tb3+dopant HAP was done to give HAP optical properties and broaden the application range of HAP.

关键词： Hydroxyapatite Rare earth luminescence Photoelectric device Aramid Polyphenylene sulfide fiber paper Luminescent fiber

Two-person device-free localization system based on ZigBee and transformer

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High Technology Letters 2024年第1期30卷 61-67页

作者：刘天蒙 YANG Hai xiao wu Hong School of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350P.R.China Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Nankai UniversityTianjin 300350P.R.China Engineering Research Center of Thin Film Optoelectronics Technology Nankai UniversityTianjin 300350P.R.China

Most studies on device-free localization currently focus on single-person scenarios.This paper proposes a novel method for device-free localization that utilizes ZigBee received signal strength indication(RSSI)and a Transformer network structure.The method aims to address the limited research and low accuracy of two-person device-free localization.This paper first describes the construction of the sensor network used for collecting ZigBee RSSI.It then examines the format and features of ZigBee data packages.The algorithm design of this paper is then introduced.The box plot method is used to identify abnormal data points,and a neural network is used to establish the mapping model between ZigBee RSSI matrix and localization coordinates.This neural network includes a Transformer encoder layer as the encoder and a fully connected network as the decoder.The proposed method's classification accuracy was experimentally tested in an online test stage,resulting in an accuracy rate of 98.79%.In conclusion,the proposed two-person localization system is novel and has demonstrated high accuracy.

关键词： device-free localization deep learning ZigBee

OCTA characteristics in non-arteritic central retinal artery occlusion and correlation with visual acuity

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 289-296页

作者： Hong-Xia Gong bin wu Shi-Yong Xie Wei Zhang Song Chen Tianjin Key Lab of Ophthalmology and Visual Science Department of Ophthalmology for Integrated Traditional Chinese and Western MedicineTianjin Eye HospitalTianjin 300020China Clinical College of Ophthalmology Tianjin Medical UniversityTianjin 300010China Eye Hospital Affiliated to Nankai University Tianjin 300020China

AIM:To observe the retinal and choroidal circulations in patients with non-arteritic permanent central retinal artery occlusion(NA-CRAO)via optical coherence tomography angiography(OCTA)and analyze their correlation with visual acuity.METHODS:Sixty-two eyes with clinically confirmed acute NA-CRAO were included in the study and divided into:A type(mild n=29),B type(moderate n=27)and C type(severe n=6)based on the degree of visual loss,retinal edema,and arterial blood flow delay in fundus fluorescence angiography(FFA).Contralateral healthy eyes were used as the control group.Best-corrected visual acuity(BCVA),slit lamp microscopy,indirect ophthalmoscopy,fundus color photography,OCTA,and FFA were performed.Spearman’s correlation analysis was used to determine the correlations between retinal and choroidal vessels and visual acuity.RESULTS:There were no statistically significant differences in age,gender,and intraocular pressure among the three types and the control group(P>0.05).Vessel density in deep capillary plexus(VD-DCP)significantly decreased(P<0.05)in all three types of NA-CRAO patients compared to the control group.Vessel density in superficial vascular plexus(VD-SVP)significantly decreased(P<0.05)in type A patients and choriocapillaris flow area significantly decreased(P<0.05)in type B and type C patients compared to the control group;while outer retinal flow areas significantly increased in the type A(P<0.05)and decreased in type C patients(P<0.05).The retinal thickness significantly increased in type C group(P<0.05).The VD-SVP at fovea in the type A was significantly lower than both of type B and C.The VD-SVP at nasal parafovea in type A and B was significantly lower than type C(P<0.05).The logMAR BCVA of type A was significantly better than that of type B and C groups(P<0.05).Spearman’s correlation analysis showed that the logMAR BCVA was positively correlated with VD-SVP at fovea(r=0.679,P=0.031)and nasal parafovea(r=0.826,P=0.013).CONCLUSION:OCTA is valuable for assessing retinal ischemia,and evaluatin

关键词： non-arteritic central retinal artery occlusion fundus fluorescence angiography optical coherence tomography angiography retinal vessel density visual acuity

Flashover Characteristics of Dry Band-water band on Hydrophobic Surfaces

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 392-400页

作者： xiaohan wu Fanghui Yin bin Cao Daiming Yang Shichao Shao Liming Wang Tsinghua-Berkeley Shenzhen Institute(TBSI) Shenzhen 518055China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Shenzhen Polytechnic School Shenzhen 518055China

Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with artificial water droplets.However,the phenomenon is not consistent with that of the contaminated composite insulators.On the test specimens covered with water droplets,there is no obvious leakage current before the flashover and no obvious relationship between flashover voltage and the conductivity of water droplets.On the contaminated composite insulator surface,there are short continuous arcs on the insulators before critical flashover,making insulators look like a luminous lantern.Considering that under these two conditions,the proportion of water along the insulation distance is different,the flashover characteristic of“dry band-water band”on a hydrophobicity surface is analyzed in the present study.The influence of the water band parameter(including length,width,and conductivity)as well as the length of dry band is studied.On this basis,the arc generation and development process of the surface covered with“dry band-water band”is analyzed.The research results improve the understanding of the flashover process on contaminated composite insulators.

关键词： Flashover characteristics hydrophobicity partial arc water band