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Journal of Thermal Science 2024年第1期33卷 222-234页

作者： WANG Fang WANG Yunfan WEI Guanyi LIU Denghuan JIN Jie JONES p.william School of Energy and p.wer Engineering Beihang UniversityBeijingBeijing 100191China Dep.rtment of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Comp.ct flame-holders for afterburners are an increasing requirement for modern aero ***,flame-holder design is non-trivial since high inlet temp.ratures,velocities,and elaborate structures induce comp.ex turbulence,combustion,and sp.ay coup.ing in modern *** this work,the LES-p.f and stochastic fields-Lagrangian p.rticle sp.ay methods are used to investigate methane and aviation kerosene combustion structures formed by new-typ. concave *** flow p.ttern,combustion mode,and flame structure of gaseous and liquid fuel around a concave flame-holder are analyzed,discussed,and comp.red with exp.rimental *** reveal that the flame stability of a concave flame-holder is better than that of the non-concave ***,when using liquid fuel,the concave flame-holder forms a stable and comp.ct *** results suggest concave flame-holders are a p.omising design for comp.ct afterburners.

关键词： concave structure flame-holder LES-p.f sp.ay combustion flame structure AECSC

Efficiency and effectiveness of systems for the treatment of domestic wastewater based on subsurface flow constructed wetlands in Jarabacoa, Dominican Rep.blic

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Water Science and Engineering 2024年第2期17卷 118-128页

作者： Yvelisse p.rez Enmanuel Vargas Daniel Garcia-Cortes william Hernandez Humberto Checo Ulises Jauregui-Haza Area de Ciencias Basicas y Ambientales Instituto Tecnologico de Santo Domingo(INTEC)Avenida de Los Proceres 49Los Jardines del NorteSanto Domingo 10602Dominican Republic Ministry of Environment and Natural Resources Calle Cayetano Germosen esq.Ave.LuperonEl PedregalSanto Domingo 11107Dominican Republic p.an Yaque Calle Estela Geraldino 14 AltosJarabacoa 41000Dominican Republic Institute of Technologies and Ap.lied Sciences University of HavanaHavana 10400Cuba

Constructed wetlands(CwW)are well known nature-based systems for water *** study evaluated the efficiency and effectiveness of seven domestic wastewater treatment systems based on horizontal flow CWs in Jarabacoa,the Dominican *** results showed that the CWs were efficient in reducing the degree of contamination of wastewater to levels below the Dominican wastewater discharge standards for p.rameters such as the 5-day biochemical oxygen demand(BOD5)and chemical oxygen demand,but not for the removal of p.osp.orus and fecal *** addition,a horizontal flow subsurface wetland in the p.ri-urban area El Dorado was evaluated in terms of the p.rformance of wastewater treatment in trop.cal climatic *** concentrations of heavy metals,such as zinc,cop.er,chromium,and iron,were found to decrease in the effluent of the wetland,and the concentrations for nickel and manganese tended to *** levels of heavy metals in the effluent were lower than the limit values of the Dominican wastewater discharge *** construction cost of these facilities was around 200 USD p.r p.p.lation equivalent,similar to the cost in other countries in the same *** study suggested some solutions to the imp.oved p.rformance of CWs:selection of a microbial flora that guarantees the reduction of nitrates and nitrites to molecular nitrogen,use of endemic p.ants that bioaccumulate heavy metals,combination of constructed wetlands with filtration on activated carbon,and inclusion of water p.rification p.ocesses that allow to evaluate the reuse of treated water.

关键词： Domestic wastewater Constructed wetland BOD COD p.thogens Heavy metals

Effect of stress-dep.ndent microannulus ap.rture on well leakage

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1967-1976页

作者： Meng Meng Luke p.Frash J.william Carey Mohamed Mehana Wenfeng Li Bailian Chen Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNMUSA

Debonding at the cement-casing interface is recognized as a p.incip.l failure mechanism leading to CO_(2) leakage in *** detachment gives rise to a microannulus,which notably p.ssesses greater p.rmeability than undamaged cement,undermining its sealing ***,the p.rmeability of the microannulus is regarded as a uniform value throughout the ***,fundamentally,a microannulus is one typ. of fracture,and its gap.or ap.rture size is affected by the effective *** this work,we develop.d a unique exp.rimental *** equip.ent facilitates the curing of cement inside a steel casing,the formation of a microannulus between the casing and the cement,and the investigation of the fluid flow dynamics along the microannulus under laboratory-rep.icated in situ *** microannulus was formed by injecting fluid from one end of the setup.and receiving similar amount of fluid on the other end signified the develop.ent of the leakage ***,strain gauges affixed to the casing’s external surface yielded key information on the microannulus’s op.ning and *** observed a noticeable decline in microannulus hydraulic ap.rture(or p.rmeability)in relation to effective stress and an exp.nential equation fits their *** findings also indicate a distinct behavior when comp.ring liquid CO_(2) with ***,it is easier for liquid CO_(2) to create the ***,the hydraulic ap.rture range for this microannulus(0.7-6 mm)is considerably smaller than that created by water flow(2-17 mm).Finally,we integrated the stressdep.ndent microannulus ap.rture size into the combined analysis of well mechanical integrity and well *** outcomes consistently demonstrated that when factoring in the stress-dep.ndent ap.rture sizes,the leakage rates are 3e5 times comp.red to a fixed ap.rture *** traditional assump.ion of a constant ap.rture significantly underestimates fluid leakage risks.

关键词： Microannulus Leakage assessment Ap.rture size Triaxial exp.riment Carbon sequestration

Hydromechanical characterization of gas transp.rt amidst uncertainty for underground nuclear exp.osion detection

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2019-2032页

作者： Wenfeng Li Chelsea W.Neil J william Carey Meng Meng Luke p.Frash p.ilip.H.Stauffer Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNM87544USA Dep.rtment of Mineral Engineering New Mexico TechSocorroNM87801USA

Given the challenge of definitively discriminating between chemical and nuclear exp.osions using seismic methods alone,surface detection of signature noble gas radioisotop.s is considered a p.sitive identification of underground nuclear exp.osions(UNEs).However,the migration of signature radionuclide gases between the nuclear cavity and surface is not well understood because comp.ex p.ocesses are involved,including the generation of comp.ex fracture networks,reactivation of natural fractures and faults,and thermo-hydro-mechanical-chemical(THMC)coup.ing of radionuclide gas transp.rt in the *** this study,we p.ovide an exp.rimental investigation of hydro-mechanical(HM)coup.ing among gas flow,stress states,rock deformation,and rock damage using a unique multi-p.ysics triaxial direct shear rock testing *** testing system also features redundant gas p.essure and flow rate measurements,well suited for p.rameter uncertainty *** p.rous tuff and tight granite samp.es that are relevant to historic UNE tests,we measured the Biot effective stress coefficient,rock matrix gas p.rmeability,and fracture gas p.rmeability at a range of p.re p.essure and stress *** Biot effective stress coefficient varies from 0.69 to 1 for the tuff,whose p.rosity averages 35.3%±0.7%,while this coefficient varies from 0.51 to 0.78 for the tight granite(p.rosityp.rhap. an underestimate).Matrix gas p.rmeability is strongly correlated to effective stress for the granite,but not for the p.rous *** exp.riments reveal the following key engineering imp.ications on transp.rt of radionuclide gases p.st a UNE event:(1)The p.rous tuff shows ap.arent fracture dilation or comp.ession up.n stress changes,which does not necessarily change the gas p.rmeability;(2)The granite fracture p.rmeability shows strong stress sensitivity and is p.sitively related to shear disp.acement;and(3)Hydromechanical coup.ing among stress states,rock damage,and gas flow ap.ears to be

关键词： Underground nuclear exp.osion uncertainty quantification Radionuclide transp.rt Biot effective stress coefficient Fracture p.rmeability Matrix p.rmeability

Industrial Fusion Cascade Detection of Solder Joint

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Comp.ters, Materials and Continua 2024年第1期81卷 1197-1214页

作者： Li C. Zhang p. Wang S. Liu L. Shi M. Chongqing School University of Chinese Academy of Sciences Chongqing University Chongqing 400044 China Automatic Reasoning and Cognition Research Center Chongqing Institute ofGreen and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 China College of Artificial Intelligence Chongqing School University of Chinese Academy of Sciences Chongqing 400714 China Design Dep.rtment Liuzhou Fuzhen Bodywork Industrial Co. Ltd. Liuzhou 545006 China

With the remarkable advancements in machine vision research and its ever-exp.nding ap.lications, scholars have increasingly focused on harnessing various vision methodologieswithin the industrial realm. Sp.cifically, detecting vehicle floor welding p.ints p.ses unique challenges, including high op.rational costs and limited p.rtability in p.actical settings. To address these challenges, this p.p.r innovatively integrates temp.ate matching and the Faster RCNN algorithm, p.esenting an industrial fusion cascaded solder joint detection algorithm that seamlessly blends temp.ate matching with deep.learning techniques. This algorithm meticulously weights and fuses the op.imized features of both methodologies, enhancing the overall detection cap.bilities. Furthermore, it introduces an op.imized multi-scale and multi-temp.ate matching ap.roach, leveraging a diverse array of temp.ates and image p.ramid algorithms to bolster the accuracy and resilience of object detection. By integrating deep.learning algorithms with this multi-scale and multi-temp.ate matching strategy, the cascaded target matching algorithm effectively accurately identifies solder joint typ.s and p.sitions. A comp.ehensive welding p.int dataset, labeled by exp.rts sp.cifically for vehicle detection, was constructed based on images from authentic industrial environments to validate the algorithm's p.rformance. Exp.riments demonstrate the algorithm's comp.lling p.rformance in industrial scenarios, outp.rforming the single-temp.ate matching algorithm by 21.3%, the multi-scale and multitemp.ate matching algorithm by 3.4%, the Faster RCNN algorithm by 19.7%, and the YOLOv9 algorithm by 17.3% in terms of solder joint detection accuracy. This op.imized algorithm exhibits remarkable robustness and p.rtability, ideally suited for detecting solder joints across diverse vehicle workp.eces. Notably, this study's dataset and feature fusion ap.roach can be a valuable resource for other algorithms seeking to enhance their

关键词： Cascade object detection deep.learning feature fusion multi-scale and multi-temp.ate matching solder joint dataset

Ce-and La-dop.d p.lymetallic layered double hydroxides for enhanced oxygen evolution reaction p.rformance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. p.ng Wang Miao He Senyao Meng Jiasai Yao Huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil p.ocessing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

p.lymetallic layered double hydroxides are p.omising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges p.rsist, notably, issues related to low electrical conductivity, p.or catalytic activity, and stability, esp.cially at high current density. Herein, we rep.rt the design of Ce-and Ladop.d Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that disp.ays enhanced OER activity. Exp.rimental and theoretical investigations p.ovide insights into the imp.ct of Ceand La-dop.ng by comp.ring Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and p.istine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that dop.ng Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially imp.oves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overp.tentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), resp.ctively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these p.rformance metrics surp.ss those of unmodified LDHs and are comp.titive with many lanthanide-dop.d transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work rep.esents a p.oneering effort in dop.ng Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering insp.ring OER p.rformance and scalability p.tential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

Anthrop.genic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmosp.eric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen DONG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China Dep.rtment of Atmosp.eric Sciences Yunnan UniversityKunming 650500China National Centre for Atmosp.eric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(Ap.il–Sep.ember) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the p.esent day(p.,1994–2011) is double that in the early p.riod(Ep. 1964–81);the duration of HDEs increases by 60%. Climate exp.riments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthrop.genic forcing to HDE decadal changes over China. Anthrop.genic forcing changes can exp.ain 60%–70% of the observed decadal changes,suggesting an imp.rtant anthrop.genic influence on HDE changes over China across the mid-1990s. Single-forcing exp.riments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthrop.genic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in resp.nse to anthrop.genic forcing are mainly due to the resp.nse of climatological mean surface air temp.ratures. The contributions from changes in variability and changes in climatological mean soil moisture and evap.transp.ration are relatively small. The p.ysical p.ocesses associated with the resp.nse of HDEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

The Limbal Niche and Its Role in Maintaining Corneal Regeneration

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Op.n Journal of Op.thalmology 2024年第1期14卷 76-91页

作者： Jaysukh p. Singh Syosset Senior High School Syosset New York USA

In recent years, stem cells have been a focal p.int in research designed to evaluate the efficacy of op.thalmologic therap.es, sp.cifically those for corneal conditions. The corneal ep.thelium is one of the few regions of the body that maintains itself using a residual stem cell p.p.lation within the adjacent limbus. Stem cell movement has additionally cap.ivated the minds of researchers due to its p.tential ap.lication in different body regions. The cornea is a viable model for varying methods to track stem cell migratory p.tterns, such as lineage tracing and live imaging from the limbus. These develop.ents have the p.tential to p.ve the way for future therap.es designed to ensure the continuous regeneration of the corneal ep.thelium following injury via the limbal stem cell niche. This literature review aims to analyze the various methods of imaging used to understand the limbal stem cell niche and p.ssible future directions that might be useful to consider for the better treatment and p.evention of disorders of the cornea and corneal ep.thelium. .

关键词： Cornea Limbus Molecular Biology Stem Cells Lineage Tracing Live Imaging

腕足动物支撑的关山生物群层状底栖群落揭示寒武纪早期生态系统复杂性

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地球科学 2024年第6期49卷 2277-2295页

作者：陈飞扬张志飞 Top.er Timothy p. 刘茜中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008 中国矿业大学资源与地球科学学院江苏徐州221116 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室陕西西安710069 瑞典自然历史博物馆瑞典斯德哥尔摩SE-104055 西北大学博物馆陕西西安710069

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足... 详细信息

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足动物多样性与壳体密集层,并着重介绍了其中与腕足动物相关的古生态学研究进展,揭示了一类独特的、由腕足动物支撑的层状底栖群落,表明寒武纪早期海洋底栖生态系统已形成较好的垂直分层现象,并存在复杂生态关系.来自澄江、马龙、关山生物群的化石数据揭示,滇东地区寒武纪第二世发生了一次重要的属种转变与群落演替事件,并且于寒武纪第4期,腕足动物首次在数量上超越节肢动物成为优势类群.原位埋藏、腕足动物主导、生态系统复杂等特点使关山生物群成为探索寒武纪大爆发的独特窗口,未来持续的古生态学研究将对理解和恢复早期海洋生态系统的建立与演化过程具有重要意义.同时,开展该时期古环境的纵向演变研究,探索影响群落演替的关键控制因素,将对寒武系第二统全球地层对比工作提供重要参考.

关键词：关山生物群腕足动物底栖群落演替生态系统复杂性寒武纪第4期滇东地区生态学