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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 188-195页

作者：白杨 LI Yan XING Lukuo LI Xiangbo WANG Zhenhua State Key Laboratory of marine Coatings Marine Chemical Research Institute Co.Ltd.Qingdao 266071China College of Mechanical and Electrical engineering University of China Petroleum(East China)Qingdao 266580China Science and Technology on marine Corrosion and Protection Laboratory Luoyang Ship Materials Research InstituteQingdao 266101China

The double-layer NiCr-Cr_(3)C_(2)/Ni-Zn-Al_(2)O_(3) coatings with sufficient corrosion and wear resistance were prepared on low carbon steel *** intermediate layers Ni-Zn-Al_(2)O_(3) were fabricated by using low-pressure cold spray (LPCS) method to improve the salt fog corrosion resistance properties of the supersonic plasma spray (SPS) NiCr-Cr_(3)C_(2) *** friction and wear performance for the double-layer and single-layer NiCr-Cr_(3)C_(2) coatings were carried out by line-contact reciprocating sliding,*** with the coating surface analysis techniques,the effect of the salt fog corrosion on the tribological properties of the double-layer coatings was *** results showed that the double-layer coatings exhibited better wear resistance than that of the single-layer coatings,due to the better corrosion resistance of the intermediate layer;the wear mass losses of the double-layer coatings was reduced by 70%than that of the single layer coatings and the wear mechanism of coatings after salt fog corrosion conditions is mainly corrosion wear.

关键词： low-pressure cold spray NiCr-Cr_(3)C_(2)coating wear behavior salt fog corrosion

Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Ecological engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–Tech Co. Ltd.Langfang065201China GRIREM Advanced Materials Co. Ltd.Beijing100088China GRIMAT engineering Institute Co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most common mining *** high contents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A comprehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary concentrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum concentration in Chongzuo samples decreases continuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the concentration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the consumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore Sequential extraction Occurrence Aluminum Rare earth elements

Road sub-surface defect detection based on gprMax forward simulation-sample generation and Swin Transformer-YOLOX

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Frontiers of Structural and Civil engineering 2024年第3期18卷 334-349页

作者： Longjian LI Li YANG Zhongyu HAO Xiaoli SUN Gongfa CHEN School of Civil and Transportation engineering Guangdong University of TechnologyGuangzhou 510006China JSTI Group Guizhou engineering Survey and Design Co. Ltd.Guangzhou 510800China Guangzhou Municipal engineering Testing Co. Ltd.Guangzhou 510520China

Training samples for deep learning networks are typically obtained through various field experiments,which require significant manpower,resource and time ***,it is possible to utilize simulated data to augment the training *** this paper,by comparing the actual experimental model with the simulated model generated by the gprMax[1]forward simulation method,the feasibility of obtaining simulated samples through gprMax simulation is ***,the samples generated by gprMax forward simulation are used for training the network to detect objects in existing real *** the same time,aiming at the detection and intelligent recognition of road sub-surface defects,the Swin-YOLOX algorithm is introduced,and the excellence of the detection network,which is improved by augmenting the simulated samples with real samples,is further *** comparing the prediction performance of the object detection models,it is observed that the model trained with mixed samples achieved a recall of 94.74%and a mean average precision(maP)of 97.71%,surpassing the model trained only on real samples by 12.95%and 15.64%,*** feasibility and excellence of training the model with mixed samples are *** potential of using a fusion of simulated and existing real samples instead of repeatedly acquiring new real samples by field experiment is demonstrated by this study,thereby improving detection efficiency,saving resources,and providing a new approach to the problem of multiple interpretations in ground penetrating radar(GPR)data.

关键词： ground penetrating radar gprMax forward modeling sample generation Swin-YOLOX object detection

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： Xue-qin Ji Xiao-song Zhang Chen-jun Yang Xiao-qian Dong State Key Laboratory of Ocean engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

Tungsten separation behavior on preparation of high-purity cerium by combined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-Tech Co. Ltd.Langfang065201China National engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials Co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a combined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was *** reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt *** enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum content of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this combined ***,this paper provides a new method for the removal of high density and low evaporation coefficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

Precipitation evolution and properties of Cu-15Ni-8Sn alloys via Al microalloying during ageing

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Rare Metals 2024年第10期43卷 5216-5228页

作者： Wei Luo Li-Jun Peng Xu-Jun Mi Hao-Feng Xie Yi-Cheng Cao Shu-Hui Huang State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd. GRIMAT engineering Institute Co. Ltd. General Research Institute for Nonferrous Metals School of Materials Science and engineering South China University of Technology

Studies have shown that microalloying Cu-Ni-Sn alloys using Al inhibits discontinuous precipitation reactions;however,the mechanism has not been investigated ***,this study explored the properties and precipitation evolution of Cu-15Ni-8Sn alloys without and with 1 wt%Al（Cu-15Ni-8Sn-1Al） during ageing at 500℃ through X-ray diffraction （XRD）,scanning electron microscopy and high-angle annular dark-field scanning transmission electron *** results revealed that in Cu-15Ni-8Sn alloy,DO22ordering first occurred after spinodal decomposition,subsequently transitioning to an L12ordering phase,during which the discontinuous precipitates gradually nucleated at the grain boundaries and formed *** alloy hardness increased sharply with ordering and then decreased rapidly after reaching its peak value,due to the dominance of the discontinuous precipitation ***,the DO22ordered phase did not appear during the ageing of Cu-15Ni-8Sn-1Al alloy,and a Ni3(Alx,Sn1-x) intermetallic compound with L12structure was formed,consuming Ni and Sn atoms,thereby significantly suppressing the discontinuous precipitation reaction and improving the stability during prolonged *** tensile strength （yield strength） of Cu-15Ni-8Sn and Cu-15Ni-8Sn-1Al alloys at peak hardness were 855 （755） and 936 MPa （892 MPa）,respectively,and their main strengthening mechanisms were solid solution strengthening and precipitation *** addition of 1 wt% Al effectively improved the precipitation strengthening effect of Cu-Ni-Sn alloys but severely decreased the ductility.

关键词： Al addition Cu-15Ni-8Sn Precipitation sequence Strengthening mechanism

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Supplementation of alanine improves biomass accumulation and lipid production of Chlorella pyrenoidosa by increasing the respiratory and metabolic processes

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Journal of Oceanology and Limnology 2024年第2期42卷 570-579页

作者： Yongfu LI Tianze ZHAO Wei SUN Ruiwen GAO Guangyuan MA Jiangsu Province engineering Research Center for marine Bioresources Sustainable Utilization Key Laboratory of Marine Hazards ForecastingMinistry of Natural ResourcesHohai UniversityNanjing 210098China College of Oceanography Hohai UniversityNanjing 210098China Jiangsu Innovation Center of marine Bioresources Jiangsu Coast Development Group Co.Ltd.Nanjing 210019China

The function of exogenous alanine(Ala)in regulating biomass accumulation,lipid production,photosynthesis,and respiration in Chlorella pyrenoidosa was *** shows that the supplementation of Ala increased *** biomass and lipid production in an 8-d batch *** concentration of 10 mmol/L of Ala was optimum and increased the microalgal cell biomass and lipid content by 39.3%and 21.4%,respectively,compared with that in the control(0-mmol/L Ala).Ala supplementation reduced photosynthetic activity while boosting respiratory activity and pyruvate levels,indicating that *** used exogenous Ala for biomass accumulation through the respiratory metabolic *** accelerated respiratory metabolism due to Ala supplementation elevated the substrate pool and improved the lipogenic gene expression,promoting lipid production at *** study provided a novel method for increasing biomass accumulation and lipid production and elucidated the role of Ala in regulating lipid production.

关键词： alanine Chlorella pyrenoidosa lipid respiration lipogenic gene

Current status and development of CMOS SiPM for scintillator-based radiation detectors toward all-digital sensors[Invited]

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Chinese Optics Letters 2024年第2期22卷 17-27页

作者： Nicola D'Ascenzo 胡文韬劳慧华越轩张博房磊奚道明郑睿邱奥 Emanuele Antonecchia 凌怡清刘雨晴李琰俞航肖鹏谢庆国 Wuhan National Laboratory for Optoelectronics Wuhan 430074China Biomedical engineering Department Huazhong University of Science and TechnologyWuhan 430074China RAYQUANT Technology Co. Ltd.Ezhou 436044China RAYSOLUTION Healthcare Co. Ltd.Hefei 230000China RAYMEASURE Technology Co. Ltd.Suzhou 215000China RAYCAN Technology Co. Ltd.Suzhou 215000China College of Computer Science and Software engineering Shenzhen UniversityShenzhen 518060China

Modern scintillator-based radiation detectors require silicon photomultipliers(Si PMs)with photon detection efficiency higher than 40%at 420 nm,possibly extended to the vacuum ultraviolet(VUV)region,single-photon time resolution(SPTR)<100 ps,and dark count rate(DCR)<150 kcps/mm^(2).To enable single-photon time stamping,digital electronics and sensitive microcells need to be integrated in the same CMOS substrate,with a readout frame rate higher than 5 MHz for arrays extending over a total area up to 4 mm×4 *** is challenging due to the increasing doping concentrations at low CMOS scales,deep-level carrier generation in shallow trench isolation fabrication,and power consumption,among *** advances at 350 and 110 nm CMOS nodes are benchmarked against available Si PMs obtained in CMOS and commercial customized *** concept of digital multithreshold Si PMs with a single microcell readout is finally reported,proposing a possible direction toward fully digital scintillator-based radiation detectors.

关键词： silicon photomultiplier complementary metal-oxide semiconductor digital SiPM

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