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An adaptive finite-difference method for seismic traveltime modeling based on 3D eikonal equation

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Petroleum Science 2024年第1期21卷 195-205页

作者： Bao-Ping Qiao Qing-Qing Li Wei-guang he Dan Zhao Qu-Bo Wu CNNC Beijing Research Institute of Uranium Geology Beijing 100029China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShangdongChina SINOPEC Geophysical Research Institute Nanjing211103JiangsuChina

3D eikonal equation is a partial differential equation for the calculation of first-arrival traveltimes and has been widely applied in many scopes such as ray tracing,source localization,reflection migration,seismic monitoring and tomographic imaging.In recent years,many advanced methods have been developed to solve the 3D eikonal equation in heterogeneous media.However,there are still challenges for the stable and accurate calculation of first-arrival traveltimes in 3D strongly inhomogeneous media.In this paper,we propose an adaptive finite-difference(AFD)method to numerically solve the 3D eikonal equation.The novel method makes full use of the advantages of different local operators characterizing different seismic wave types to calculate factors and traveltimes,and then the most accurate factor and traveltime are adaptively selected for the convergent updating based on the Fermat principle.Combined with global fast sweeping describing seismic waves propagating along eight directions in 3D media,our novel method can achieve the robust calculation of first-arrival traveltimes with high precision at grid points either near source point or far away from source point even in a velocity model with large and sharp contrasts.Several numerical examples show the good performance of the AFD method,which will be beneficial to many scientific applications.

关键词： 3D eikonal equation Accurate traveltimes Global fast sweeping 3D inhomogeneous media Adaptive finite-difference method

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Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research(International) 2024年第2期31卷 475-487页

作者： Shi-guang Xu Jin-shan he Run-ze Zhang Fu-cheng Zhang Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation conditions.The order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain rate.Meanwhile,the effect of holding time on static recrystallization behaviors is significantly controlled by temperature.In addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to cSRX.The cSRX exists at all temperatures.This is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of dislocation.Large undissolved sigma precipitates promote static recrystallization through particle-stimulated nucleation.However,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

Proteomic study of vitreous in proliferative diabetic retinopathy patients after treatment with aflibercept:a quantitative analysis based on 4D label-free technique

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 676-685页

作者： Ting-Ting Feng Xiang Gao An-Ran Liang Bo-Wen Zhao guang-Hui he Song Chen Clinical College of Ophthalmology Tianjin Medical UniversityTianjin 300070China Tianjin Key Laboratory of Ophthalmology and Visual Science Tianjin Eye InstituteTianjin Eye HospitalTianjin 300020China Key Laboratory of Ophthalmology Anyang Eye HospitalAnyang 455000Henan ProvinceChina Department of Ophthalmology Jining No.1 People’s HospitalJining 272011Shandong ProvinceChina

AIM:To identify different metabolites,proteins and related pathways to elucidate the causes of proliferative diabetic retinopathy(PDR)and resistance to anti-vascular endothelial growth factor(VEGF)drugs,and to provide biomarkers for the diagnosis and treatment of PDR.METHODS:Vitreous specimens from patients with diabetic retinopathy were collected and analyzed by Liquid Chromatography-Mass Spectrometry(LC-MS/MS)analyses based on 4D label-free technology.Statistically differentially expressed proteins(DEPs),Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway representation and protein interactions were analyzed.RESULTS:A total of 12 samples were analyzed.The proteomics results showed that a total of 58 proteins were identified as DEPs,of which 47 proteins were up-regulated and 11 proteins were down-regulated.We found that C1q and tumor necrosis factor related protein 5(C1QTNF5),Clusterin(CLU),tissue inhibitor of metal protease 1(TIMP1)and signal regulatory protein alpha(SIRPα)can all be specifically regulated after aflibercept treatment.GO functional analysis showed that some DEPs are related to changes in inflammatory regulatory pathways caused by PDR.In addition,protein-protein interaction(PPI)network evaluation revealed that TIMP1 plays a central role in neural regulation.In addition,CD47/SIRPαmay become a key target to resolve anti-VEGF drug resistance in PDR.CONCLUSION:Proteomic analysis is an approach of choice to explore the molecular mechanisms of PDR.Our data show that multiple proteins are differentially changed in PDR patients after intravitreal injection of aflibercept,among which C1QTNF5,CLU,TIMP1 and SIRPαmay become targets for future treatment of PDR and resolution of anti-VEGF resistance.

关键词： vitreous proliferative diabetic retinopathy proteome 4D label-free

Understand the Temperature Sensing Behavior of Solid-state Polymerized PEDOT Hybrid Based on X-ray Scattering Studies

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Chinese Journal of Polymer Science 2024年第1期42卷 105-112,I0010页

作者： Zhen-Hang he guang-Feng Liu Ze-Kun Zhou Zhen Liu Yi-Shu Zeng Peng Zhang School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-sen UniversityGuangzhou 510275China Shanghai Advanced Research Institute(Zhangjiang Laboratory) Chinese Academy of SciencesShanghai 201204China

Poly(3,4-ethylenedioxythiophene)(PEDOT) is one of the most successful conductive polymers that recently has been used in wearable sensors for human health monitoring. In this work, we prepared a series of PEDOT hybrids consisting of PEDOT, sodium poly(styrene sulfonate)(PSSNa) and polyethylene oxide(PEO), and their preparation could be scaled-up via an adapted solid-state polymerization process. The resistance of the as-prepared PEDOT:PSS/PEO hybrid shows clear temperature response, i.e., it decreases almost linearly with the temperature increase. To understand this phenomenon, the in situ synchrotron radiation wide-and small-angle X-ray scattering(WAXS/SAXS) characterizations were undertaken to study the temperature-dependent microstructure change of the PEDOT:PSS/PEO hybrid. It demonstrated that PEDOT formed conductive paths in the hybrids, which were not destroyed by the PEO crystallization. As temperature increased, the PEO crystals' melting and the accompanying reorganization of PEDOT chains endowed the hybrid sample temperature responsiveness. Based on these fundamental knowledges, the hybrid materials were used to fabricate flexible wearable sensor that showing temperature sensing performance with an accuracy of 1 ℃. These findings shed lights on the scalable manufacturing of wearable sensors for body temperature monitoring.

关键词： Solid-state polymerization PEDOT hybrid Structure-property correlation X-ray scattering

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Distribution of licensed acupuncturists and educational institutions in the United States at the start of 2023,during the late stage of the COVID-19 pandemic

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Journal of Integrative Medicine 2024年第4期22卷 379-384页

作者： Arthur Yin Fan De-guang he Anu Sangraula Sarah Faggert Alemi Amy Matecki American Traditional Chinese Medicine Association McLean Center for Complementary and Alternative Medicine New England School of Acupuncture Massachusetts College of Pharmacy and Health Sciences Lombardi Comprehensive Cancer Center Cancer Prevention and Control Program Georgetown University Eastern Roots Wellness PLC Sutter health Alta Bates Summit Medical Center

This study was conducted to identify the number and density of active licensed acupuncturists(LAcs), as well as the number of accredited schools in acupuncture and Oriental medicine(AOM), as of January 1,2023, in the United States(U.S.). The number of active LAcs as of January 1, 2023 was 34,524, potentially33,364 after removing license duplication in multiple states, among which the largest three states were California(with 7317 LAcs [21.19% of the total]), New York(5024 [14.55%]) and Florida(2644 [7.66%]).The total number of LAcs decreased by 8.87% from 2018, and fell short of our projected number of LAcs in 2023 by 9037, or 20.75%. The overall LAc density in the U.S.Dmeasured as the number of LAcs per 100,000 populationDwas 10.36, less than in 2018. There were 56 active, accredited AOM schools which offered a total of 147 programs(121 at the level necessary for licensing [entry-level], 12 for an advanced practicing degree [advanced-level], and 14 for certifications). Broken down further, offerings included 50 master's degrees in acupuncture, 40 master's degrees in Oriental medicine, 31 entry-level doctorate degrees(10 in acupuncture and 21 in acupuncture plus Chinese herbal medicine), and 12advanced-level doctorate degrees in AOM. The certification programs included one in East-Asian Medical Bodywork and 13 in CHM. Among these schools in 2023, institutions in the West and East Coast states comprised 67.86%(decreased from 77.42% in 2018) of the national total. California, Florida and Illinois represented 39.29%. There were 48 jurisdictions with acupuncture practice laws in place.The data suggests that the acupuncture profession in the U.S. has been significantly impacted during the coronavirus disease 2019 pandemic.

关键词： Acupuncture educational institution Acupuncturist Density Distribution Oriental medicine United States

Urea-induced interfacial engineering enabling highly reversible aqueous zinc-ion battery

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Rare Metals 2024年第4期43卷 1599-1609页

作者： Bin-Rui Xu Quan-An Li Yong Liu guang-Bin Wang Zi-he Zhang Feng-Zhang Ren School of Material Science and Engineering Henan University of Science and Technology School of Information Engineering Henan University of Science and Technology Longmen Laboratory Provincial and Ministerial Co-Construction of Collaborative Innovation Center for Non-Ferrous Metal New Materials and Advanced Processing Technology

Aqueous zinc-ion batteries（AZIBs） have been regarded as prospective rechargeable energy storage devices because of the high theoretical capacity and low redox potential of Zn metal.However,the uncontrollable formation of dendrites and the water-induced side reactions at the Zn/electrolyte interface,and the poor reversibility under a high current density(> 2 mA·cm-2) and large area capacity(>2 mAh·cm-2) still limit the practical applications of AZIBs.Therefore,a strategy that can overcome these difficulties is urgently needed.here,we introduce an environmentally friendly and low-cost additive,namely urea,to the electrolyte of AZIBs to induce uniform Zn deposition and suppress the side reactions.Measurements of the adsorption behavior,electrochemical characterization,and observations of the morphology revealed the interfacial modification induced by urea on the Zn/electrolyte interface,demonstrating its huge potential in AZIBs.Consequently,the long-term cycling stability（over2100 h） of a Zn/Zn symmetric cell under a high current density of 5 mA·cm-2and a capacity of 5 mAh·cm-2was achieved with a 1 mol·L-1ZnSO4electrolyte with the urea additive.Additionally,the assembled Zn/NH4V4O10full cell with urea exhibited excellent cycling performance and an outstanding average Coulombic efficiency of 99.98%.These results indicate that this is a low-cost and effective additive strategy for realizing highly reversible AZIBs.

关键词： Zn anode Urea additive Interface engineering Dendrite growth Side reaction

Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria

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Petroleum Science 2024年第2期21卷 1320-1332页

作者： Jian-Yu he Fei Xie Dan Wang guang-Xin Liu Ming Wu Yue Qin College of Petroleum Engineering Liaoning Petrochemical UniversityFushun113001LiaoningChina Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun113001LiaoningChina State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China PipeChina West East Gas Pipeline Company Shanghai200120China

Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.

关键词： Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines

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Reaction mechanism between Al_(2)O_(3)–MgO refractory materials and rare earth high-carbon heavy rail steel

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1153-1163页

作者： Yi Wang guang-jie Song Ping Shen Jian-zhong he Da-xian Zhang Jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production costs.To explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)O_(3)–MgO refractories and SiO2-coated Al_(2)O_(3)–MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)O_(3)–MgO refractory was found to be more suitable.The results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction layer.Calculations based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface tension.Controlling the inclusions at a smaller size has a specific effect on alleviating the erosion of refractories.Combined with the erosion mechanism of Al_(2)O_(3)–MgO refractories,the interface reaction mechanism between Al_(2)O_(3)–MgO refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)O_(3)-MgO refractory Adhesion Surface tension Interface interaction

Impact of COVID-19-related lifestyle changes on diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 97-106页

作者： Bryce P.Johnson Yu-guang he Zachary M.Robertson Angeline Wang Rafael L.Ufret-Vincenty Department of Ophthalmology UT Southwestern Medical CenterDallasTexas 75390-9057USA

AIM:To assess diabetic macular edema(DME)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office visits.METHODS:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DME seen on 3 separate visits between January 2019 and July 2021.Period 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was March 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).Main outcome measures included visual acuity,body mass index(BMI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DME treatment(s)received at each visit.To facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT imaging.RESULTS:There was no change of BMI,systolic BP,and diastolic BP between any of the time periods.HbA1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).Macular thickness decreased for 100%of macular regions.The central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BMI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in DME.CONCLUSION:DME doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant improvement.While identifying a mechanism behind our findings is beyond the scope of this study,potential explanations may include a delay in retinal changes beyo

关键词： COVID-19 diabetic macular edema diabetic retinopathy optical coherence tomography