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Photoacoustic elastography based on laser-excited shear wave

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 56-72页

作者： Yang liu Ruoyi shi Gang li Mingjian sun School of Astronautics Harbin Institute of TechnologyHarbin 150000P.R.China School of Information Science and Engineering Harbin Institute of TechnologyWeihai 264200P.R.China

Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of *** this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound *** using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be *** laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear *** frequency of shear wave induced by laser is higher and the frequency band is *** tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of *** feasibility of the method is verified by *** with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the *** addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is *** to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity.

关键词： Elastography shear wave photoacoustic Young's modulus

Analysis of Tidal Current Energy Potential in the Major Channels of the Bohai Strait Based on Delft3D

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Journal of Ocean University of China 2024年第4期23卷 859-870页

作者： MA Pengcheng shi Hongyuan XUE Huaiyuan li Pingping sun Yongkang School of Hydraulic Engineering Ludong University of ChinaYantai 264025China Institute of Coastal Research Ludong University of ChinaYantai 264025China Yantai Kekan Marine Technology Co. Ltd.Yantai 264025China

The utilization and development of tidal current energy can help alleviate the current energy shortage,improve the global ecological environment,and maintain sustainable *** this study,numerical simulation is carried out on a rectangular grid using *** tidal current energy potential of the major channels in the Bohai Strait is further simulated and estimated by comparing the simulated and measured *** show that the flow module in Delft3D has good modeling ability for the assessment of tidal current energy *** average flow velocity,maximum flow velocity,and energy flow density are *** Laotieshan Channel,located in the northern part of the Bohai Strait,shows a large tidal current energy *** maximum flow velocity of this channel can reach 2 m s-1,and the maximum energy flow density can exceed 500 W *** tidal current energy in the Laotieshan Channel is more than 10 times that in other ***,this study advocates for the continued exploration and exploitation of the tidal current energy resources in the Laotieshan Channel.

关键词： Delft3D Bohai Strait tidal current energy numerical simulation power density

A Novel Gymnosperm Wood from the Lopingian(Late Permian)in Zhangzi,Shanxi,North China and Its Paleoecological and Paleogeographic Implications

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Journal of Earth Science 2024年第1期35卷 167-176页

作者： Xiao shi Jianxin Yu Yuewu sun Zhen Xu Hui li College of Earth Sciences Jilin UniversityChangchun 130061China International Center of Future Science Dinosaur Evolution Research CenterJilin UniversityChangchun 130012China State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China Research Center of Palaeontology and Stratigraphy Jilin UniversityChangchun 130026China Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China

The Permian-Triassic transition saw extreme climatic changes that severely impacted the terrestrial *** plants,particularly fossil woods,are sensitive to climatic changes,and they,therefore,are unique materials revealing extreme environmental and climatic changes on land at that *** conifer woods were discovered in the Lopingian(Late Permian)strata of the sunjiagou Formation in Shanxi Province,North *** newly finding permineralized woods record the unique landscape of Lopingian North *** represent a new conifer genus and species:Shanxiopitys zhangziensis *** *** of growth pattern and anatomical characteristics of the fossil woods indicate these trees grew under optimal growing conditions,and without seasonal growth ***,climate signals from leaf fossils,vertebrate fossils and sedimentary evidences indicate a strongly seasonal climate in North China during the ***,it is speculated that these trees likely lived in the gallery forests,which were distributed along the paleo-rivers within a seasonal landscape in the central North China block during the Lopingian.

关键词： Shanxiopitys zhangziensis gen.et sp.nov. wood ecology geography gallery forest Lopingian North China

ccdc141 is required for left-right axis development by regulating cilia formation in the Kupffer's vesicle of zebrafish

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Journal of Genetics and Genomics 2024年第9期51卷 934-946页

作者： Pengcheng Wang Wenxiang shi Sijie liu Yunjing shi Xuechao Jiang Fen li sun Chen Kun sun Rang Xu Department of Pediatric Cardiology Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Department of Cardiovascular Medicine Heart Failure CenterRuijin HospitalRuijin Hospital Lu Wan BranchShanghai Jiao Tong University School of MedicineShanghai 200025China Scientific Research Center Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Department of Pediatric Cardiology Shanghai Children's Medical CenterShanghai Jiao Tong University School of MedicineShanghai 200127China

Laterality is a crucial physiological process intricately linked to the cilium-centrosome complex during embryo *** in the process can result in severe organ ***-coil domain containing 141(CCDC141)has been previously known as a centrosome-related gene,but its role in left-right(LR)asymmetry has not been *** this study,we utilize the zebrafish model and human exome analysis to elucidate the function of ccdc141 in laterality *** knockdown of ccdc141 in zebrafish disrupts early LR signaling pathways,cilia function,and Kupffer's vesicle *** ccdc141-knockdown embryos exhibiting aberrant LR patterns,ccdc141-null mutants show no apparent abnormality,suggesting a genetic compensation response *** parallel,we observe a marked reduction inα-tubulin acetylation levels in the ccdc141 *** treatment with histone deacetylase(HDAC)inhibitors,particularly the HDAC6 inhibitor,rescues the ccdc141 crispant ***,exome analysis of 70 patients with laterality defects reveals an increased burden of CCDC141 mutations,with in-vivo studies verifying the pathogenicity of the patient mutation *** findings highlight the critical role of ccdc141 in ciliogenesis and demonstrate that CCDC141 mutations lead to abnormal LR patterns,identifying it as a candidate gene for laterality defects.

关键词： Left-right axis Cilia WES Laterality defects Zebrafish CCDC141

MIDNet:Deblurring Network for Material Microstructure Images

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Computers, Materials & Continua 2024年第4期79卷 1187-1204页

作者： Jiaxiang Wang Zhengyi li Peng shi Hongying Yu Dongbai sun National Center for Materials Service Safety University of Science and Technology BeijingBeijing100083China School of Materials Sun Yat-Sen UniversityShenzhen518107China School of Materials Science and Engineering Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-Sen UniversityGuangzhou510006China

Scanning electron microscopy(SEM)is a crucial tool in the field of materials science,providing valuable insightsinto the microstructural characteristics of ***,SEM images often suffer from blurrinesscaused by improper hardware calibration or imaging automation errors,which present challenges in analyzingand interpretingmaterial ***,rectifying the blurring of these images assumes paramountsignificance to enable subsequent *** address this issue,we introduce a Material Images DeblurringNetwork(MIDNet)built upon the foundation of the Nonlinear Activation Free Network(NAFNet).MIDNetis meticulously tailored to address the blurring in images capturing the microstructure of *** keycontributions include enhancing the NAFNet architecture for better feature extraction and representation,integratinga novel soft attention mechanism to uncover important correlations between encoder and decoder,andintroducing newmulti-loss functions to improve training effectiveness and overallmodel *** conducta comprehensive set of experiments utilizing the material blurry dataset and compare them to several state-of-theartdeblurring *** experimental results demonstrate the applicability and effectiveness of MIDNet in thedomain of deblurring material microstructure images,with a PSNR(Peak Signal-to-Noise Ratio)reaching 35.26 dBand an SSIM(Structural Similarity)of *** dataset is available at:https://***/woshigui/MIDNet.

关键词： Image deblurring material microstructure attention mechanism deep learning

Double casing warhead with sandwiched charge:The axial distribution of fragments velocities

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Defence Technology（防务技术） 2024年第4期34卷 201-216页

作者： Ping Ye Yongxiang Dong Qitian sun Peizhuo shi Wang Yao Yongnan li Yujing li Mingze li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine the maximum fragment *** current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment *** this type of warhead,the simulation of the dispersion characteristics of the detonation products at different positions shows that the detonation products at the ends have a much larger axial velocity than those in the middle,and the detonation products have a greater axial dispersion velocity when they are closer to the central *** loading process and the fragment velocity vary with the axial position for both casing layers,and the total velocity of the fragments is the vector sum of the radial velocity and the axial *** the same axial position,the acceleration time of the inner casing is greater than that of the outer *** the same casing,the fragments generated at the ends have a longer acceleration time than the fragments from the *** proposed formula is validated with the X-ray radiography results of the four warheads previously tested experimentally and the 3D smoothedparticle hydrodynamics numerical simulation results of several series of new warheads with different *** formula can accurately and reliably calculate the fragment velocity when the lengthto-diameter ratio of the charge is greater than 1.5 and the thickness of the casing is less than 20%its inner *** work thus provides a key reference for the theoretical analysis and the design of warheads with multiple casings.

关键词： Double casing warhead Sandwiched charge Fragment velocity Rarefaction wave Gurney formula Explosive loading

Nano-Au-decorated hierarchical porous cobalt sulfide derived from ZIF-67 toward optimized oxygen evolution catalysis:Important roles of microstructures and electronic modulation

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Carbon Energy 2024年第5期6卷 1-14页

作者： Hongyu Gong Guanliang sun Wenhua shi Dongwei li Xiangjun Zheng Huan shi Xiu liang Ruizhi Yang Changzhou Yuan Department of New Energy Materials School of Environmental and Chemical EngineeringJiangsu University of Science and TechnologyZhenjiangJiangsuChina Advanced Materials Institute Qilu University of Technology(Shandong Academy of Sciences)JinanShandongChina Shandong Saikesaisi Hydrogen Energy Co. Ltd.JinanShandongChina Department of Materials Science and Engineering School of Materials Science&EngineeringUniversity of JinanJinanShandongChina Department of New Energy Science and Engineering College of EnergySoochow Institute for Energy and Materials InnovationsSoochow UniversitySuzhouJiangsuChina

Enhancing both the number of active sites available and the intrinsic activity of Co-based electrocatalysts simultaneously is a desirable ***,a ZIF-67-derived hierarchical porous cobalt sulfide decorated by Au nanoparticles(NPs)(denoted as HP-Au@CoxSy@ZIF-67)hybrid is synthesized by low-temperature sulfuration *** well-defined macroporous-mesoporous-microporous structure is obtained based on the combination of polystyrene spheres,as-formed CoxSy nanosheets,and ZIF-67 *** novel three-dimensional hierarchical structure significantly enlarges the three-phase interfaces,accelerating the mass transfer and exposing the active centers for oxygen evolution *** electronic structure of Co is modulated by Au through charge transfer,and a series of experiments,together with theoretical analysis,is performed to ascertain the electronic modulation of Co by ***,HP-Au@CoxSy@ZIF-67 catalysts with different amounts of Au were synthesized,wherein Au and NaBH4 reductant result in an interesting“competition effect”to regulate the relative ratio of Co^(2+)/Co^(3+),and moderate Au assists the electrochemical performance to reach the highest ***,the optimized HP-Au@CoxSy@ZIF-67 exhibits a low overpotential of 340 mV at 10 mA cm^(-2)and a Tafel slope of 42 mV dec-1 for OER in 0.1 M aqueous KOH,enabling efficient water splitting and Zn-air battery *** work here highlights the pivotal roles of both microstructural and electronic modulation in enhancing electrocatalytic activity and presents a feasible strategy for designing and optimizing advanced electrocatalysts.

关键词： Au nanoparticles cobalt sulfide electronic modulation hierarchical porous structure oxygen evolution reaction

Catalytic degradation of chlorinated volatile organic compounds(CVOCs)over Ce-Mn-Ti composite oxide catalysts

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Journal of Environmental Sciences 2024年第4期138卷 326-338页

作者： Zhiwei Zhou Qianqian li Guijin Su Jiaxin Pang Bohua sun Jing Meng Bin shi Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Developing industrially moldable catalysts with harmonized redox performance and acidity is of great significance for the efficient disposal of chlorinated volatile organic compounds(CVOCs)in actual exhaust ***,commercial TiO_(2),typically used for molding catalysts,was chosen as the carrier to fabricate a series of Ce_(0.02)Mn_(0-0.24)TiO_(x) materials with different Mn doping ratios and employed for chlorobenzene(CB)*** introduction of Mn remarkedly facilitated the synergistic effect of each element via the electron transfer processes:Ce^(3+)+Mn^(4+/3+)■Ce^(4+)+Mn^(3+/2+)and Mn^(4+/3+)+Ti^(4+)■Mn^(3+/2+)+Ti^(3+).These synergistic interactions in Ce_(0.02)Mn_(0.04-0.24)TiO_(x),especially Ce_(0.02)Mn_(0.16)TiO_(x),significantly elevated the active oxygen species,oxygen vacancies and redox properties,endowing the superior catalytic oxidation of *** the Mn doping amount increased to 0.24,a separate Mn_(3)O_(4) phase appeared,which in turn might weaken the synergistic ***,the acidity of Ce_(0.02)Mn_(0.04-0.24)TiO_(x) was decreased with the Mn doping,regulating the balance of redox property and ***,Ce_(0.02)Mn_(0.16)TiO_(x) featured relatively abundant B-acid *** coordinating redox ability and moderate acidity promoted the deep oxidation of CB and RCOOH-intermediates,as well as the rapid desorption of Cl species,thus obtaining sustainable *** comparison,CeTiO_(x) owned the strongest acidity,however,its poor redox property was not sufficient for the timely oxidative decomposition of the easier adsorbed CB,resulting in its rapid *** finding provides a promising strategy for the construction of efficient commercial molding catalysts to decompose the industrial-scale CVOCs.

关键词： Chlorobenzene Ce_(0.02)Mn_(0-0.2)4tiox materials Redox ability Acidity Synergistic interaction

Synergistically enhanced dielectric, insulating and thermally conductive performances of sandwich PMMA based dielectric films

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Progress in Natural Science:Materials International 2024年第3期34卷 591-597页

作者： Dongmei Zhang Yufan li Yuchao li Zhonggui sun Hanxue Zhu Lujia Yang Yanhu Zhan Yankai li shi Wang Jun-Wei Zha School of Mathematical Sciences Liaocheng University School of Materials Science and Engineering Liaocheng University State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications School of Chemistry and Biological Engineering University of Science and Technology Beijing

A tri-layered(B-G-B) dielectric films were simply prepared by alternatively spin-coating boron nitride/polymethylmethacrylate(BN/PMMA, B) and graphene nanosheets(GNS/PMMA, G) compound solutions. The structure, morphology, thermal conductivity, and particularly the dielectric and relaxation behaviors were systematically studied. Results showed that a good exfoliation and dispersion of BN and GNS can be simply achieved through intensive mechanical compounding with PMMA in the internal mixer. The dielectric constant and breakdown strength of the obtained 1-3-1(B-G-B) sandwich composite film reached 4.3(@1 kHz) and 458.6kV/mm, being 119 % and 113 % higher than that of pure PMMA, respectively. Furthermore, the overall thermal conductivity of sandwich 1-3-1 composite increased by 112 % due to the addition of thermally conductive BN and GNS. The sandwich design strategy provided an effective way of achieving good permittivity, high insulation, and improved thermal conductivity simultaneously, showing potential applications in the miniaturization and integration of electronic devices.

关键词： Breakdown strength Composites Dielectric constant Sandwich structure Thermal conductivity