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The profile of sound speed and dissolved oxygen in the polymetallic nodules depositional area in the Western Pacific

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Journal of Oceanology and limnology 2023年第6期41卷 2090-2100页

作者： Bowen li Yonggang JIA Zhihan FAN Kai Li College of Oceanography and Space Information China University of PetroleumQingdao 266580China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China

With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodule mining cannot be ignored.However,duo to the lacks in stable and safe deep-sea(the depth>1000 m)vertical profile observation systems and consequently in long-term in-situ observation data,the sound speed and dissolved oxygen and the other water environment factors in the deposition areas of polymetallic nodules remains poorly understood.In this study,a deep-sea in-situ observation system was designed and deployed,and the water environment data of the polymetallic nodule deposition area were collected and analyzed.Result shows that the dissolved oxygen in the depth of 0–600 m was mainly affected by biological factors,while that in the area deeper than 600 m was affected by physical factors.The sound speed in the water body was mainly affected by temperature and pressure.At depths below 840 m,the sound speed is mainly controlled by temperature,and at depths between 840 m and 5700 m,the sound speed is mainly controlled by pressure.The correlations of sound speed vs.pressure and vs.temperature were regressed into equation.The resuspension of sediments rich in various metals may result in the reduction of dissolved oxygen and the improvement of redox potential.This environmental impact caused by a single sediment resuspension could last for 24 h or more.These findings enrich the understanding of the background value of the water environment in the polymetallic nodule deposition area.

关键词： deep sea dissolved oxygen redox potential sound speed conductivity

The First Photometric Analysis of Two Low Mass Ratio Totally Eclipsing Contact Binaries:TIC 393943031 and TIC 89428764

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Research in Astronomy and Astrophysics 2022年第3期22卷 80-87页

作者： Yan-Ke Tang Ya-Ni Guo Kai Li Ning Gai Zhi-Kai Li College of Physics and Electronic Information Dezhou UniversityDezhou 253023China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

Photometric analysis of the contact binaries TIC 393943031 and TIC 89428764 was carried out using Transiting Exoplanet Survey Satellite and SuperWASP data for the first time.Using the Wilson–Devinney code,we have found that TIC 393943031 is a low-mass-ratio deep contact binary with a fillout factor of 50.9(±1)%and a mass ratio of q=0.163±0.001.TIC 89428764 is a medium and low-mass-ratio contact binary with a fillout factor of 34.5(±1)%and a mass ratio of q=0.147±0.001.Furthermore,the period study reveals both the stars exhibit continuously increasing periods,the increasing rate is 4.21×10^(−7)day yr^(−1) for TIC 393943031 while 6.36×10^(−7)day yr^(−1) for TIC 89428764.The possible reason is mass transfer from the secondary component to the primary component for both stars.Meanwhile,we discussed their evolutionary phases and orbital angular momenta.

关键词： Stars (stars:)binaries:eclipsing stars:low-mass

Effect of boundary conditions on shakedown analysis of heterogeneous materials

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 39-68页

作者： Xiuchen GONG Yinghao NIE Gengdong CHENG Kai Li State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentInternational Research Center for Computational MechanicsDepartment of Engineering MechanicsDalian University of TechnologyDalian 116023Liaoning ProvinceChina

The determination of the ultimate load-bearing capacity of structures made of elastoplastic heterogeneous materials under varying loads is of great importance for engineering analysis and design. Therefore, it is necessary to accurately predict the shakedown domains of these materials. The static shakedown theorem, also known as Melan's theorem, is a fundamental method used to predict the shakedown domains of structures and materials. Within this method, a key aspect lies in the construction and application of an appropriate self-equilibrium stress field(SSF). In the structural shakedown analysis, the SSF is typically constructed by governing equations that satisfy no external force(NEF) boundary conditions. However, we discover that directly applying these governing equations is not suitable for the shakedown analysis of heterogeneous materials. Researchers must consider the requirements imposed by the Hill-Mandel condition for boundary conditions and the physical significance of representative volume elements(RVEs). This paper addresses this issue and demonstrates that the sizes of SSFs vary under different boundary conditions, such as uniform displacement boundary conditions(DBCs), uniform traction boundary conditions(TBCs), and periodic boundary conditions(PBCs). As a result, significant discrepancies arise in the predicted shakedown domain sizes of heterogeneous materials. Built on the demonstrated relationship between SSFs under different boundary conditions, this study explores the conservative relationships among different shakedown domains, and provides proof of the relationship between the elastic limit(EL) factors and the shakedown loading factors under the loading domain of two load vertices. By utilizing numerical examples, we highlight the conservatism present in certain results reported in the existing literature. Among the investigated boundary conditions, the obtained shakedown domain is the most conservative under TBCs.Conversely, utilizing PBCs to construct an SSF for the shakedown analysis lea

关键词： heterogeneous material self-equilibrium stress field(SSF) shakedown analysis effect of boundary conditions

Effects of benthic hydraulics on sediment oxygen demand in a canyon-shaped deep drinking water reservoir:Experimental and modeling study

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Journal of Environmental Sciences 2021年第4期33卷 226-234页

作者： Nan li Tinglin Huang Zhiying Chang Kai Li Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Sediment oxygen demand(SOD)is a major contributor to hypolimnetic oxygen depletion and the release of internal nutrient loading.By measuring the SOD in experimental chambers using in both dissolved oxygen(DO)depletion and diffusional oxygen transfer methods,a model of SOD for a sediment bed with water current-induced turbulence was presented.An experimental study was also performed using near-sediment vertical DO profiles and correlated hydraulic parameters stimulated using a computational fluid dynamics model to determine how turbulences and DO concentrations in the overlying water affects SOD and diffusive boundary layer thickness.The dependence of the oxygen transfer coefficient and diffusive boundary layer on hydraulic parameters was quantified,and the SOD was expressed as a function of the shear velocity and the bulk DO concentrations.Theoretical predictions were validated using microelectrode measurements in a series of laboratory experiments.This study found that flow over the sediment surface caused an increase in SOD,attributed to enhanced sediment oxygen uptake and reduced substances fluxes,i.e.,for a constant maximum biological oxygen consumption rate,an increased current over the sediment could increase the SOD by 4.5 times compared to stagnant water.These results highlight the importance of considering current-induced SOD increases when designing and implementing aeration/artificial mixing strategies.

关键词： Sediment oxygen demand Sediment-water flux Diffusive boundary layer thickness Turbulence Biological oxygen consumption

Local stability analysis of a low-dissipation cyclic refrigerator

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Communications in Theoretical Physics 2022年第1期74卷 115-123页

作者： Kai Li Jie lin Jian-Hui Wang Department of Physics Nanchang UniversityNanchang 330031China State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China

We study the local stability near the maximum figure of merit for the low-dissipation cyclic refrigerator,where the irreversible dissipation occurs not only in the thermal contacts but also the adiabatic strokes.We find that the bounds of the coefficient of performance at a maximum figure of merit or maximum cooling rate in the presence of internal dissipation are identical to those in the corresponding absence of internal dissipation.Using two different scenarios,we prove the existence of a single stable steady state for the refrigerator,and clarify the role of internal dissipation on the stability of the thermodynamic steady state,showing that the speed of system evolution to the steady state decreases due to internal dissipation.

关键词： local stability system dynamics low dissipation cyclic refrigerator

FGF13 suppresses acute myeloid leukemia by regulating bone marrow niches

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Frontiers of Medicine 2022年第6期16卷 896-908页

作者： Ran li kai Xue Junmin li Shanghai Institute of Hematology State Key Laboratory of Medical GenomicsNational Research Center for Translational Medicine at ShanghaiRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China

Fibroblast growth factor 13(FGF13)is aberrantly expressed in multiple cancer types,suggesting its essential role in tumorigenesis.Hence,we aimed to explore its definite role in the development of acute myeloid leukemia(AML)and emphasize its associations with bone marrow niches.Results showed that FGF13 was lowly expressed in patients with AML and that its elevated expression was related to prolonged overall survival(OS).Univariate and multivariate Cox regression analyses identified FGF13 as an independent prognostic factor.A prognostic nomogram integrating FGF13 and clinicopathologic variables was constructed to predict 1-,3-,and 5-year OS.Gene mutation and functional analyses indicated that FGF13 was not associated with AML driver mutations but was related to bone marrow niches.As for immunity,FGF13 was remarkably associated with T cell count,immune checkpoint genes,and cytokines.In addition,FGF13 overexpression substantially inhibited the growth and significantly induced the early apoptosis of AML cells.The xenograft study indicated that FGF13 overexpression prolonged the survival of recipient mice.Overall,FGF13 could serve as an independent prognostic factor for AML,and it was closely related to the bone marrow microenvironment.

关键词： acute myeloid leukemia FGF13 prognosis immune-related genes bone marrow niches

High Speed Machining for linear Paths Blended with G3 Continuous Pythagorean-Hodograph Curves

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Journal of Systems Science & Complexity 2022年第4期35卷 1586-1607页

作者： ZHAO kai li Shurong College of Control Science and Engineering China University of Petroleum(East China)Qingdao266580China College of Computer Science and Information Engineering Anyang Institute of TechnologyAnyang455000China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing100876China

Previously,many studies have illustrated corner blend problem with different parameter curves.Only a few of them take a Pythagorean-hodograph(PH)curve as the transition arc,let alone corresponding real-time interpolation methods.In this paper,an integrated corner-transition mixing-interpolation-based scheme(ICMS)is proposed,considering transition error and machine tool kinematics.Firstly,the ICMS smooths the sharp corners in a linear path through blending the linear path with G3 continuous PH transition curves.To obtain optimal PH transition curves globally,the problem of corner smoothing is formulated as an optimization problem with constraints.In order to improve optimization efficiency,the transition error constraint is deduced analytically,so is the curvature extreme of each transition curve.After being blended with PH transition curves,a linear path has become a blend curve.Secondly,the ICMS adopts a novel mixed interpolator to process this kind of blend curves by considering machine tool kinematics.The mixed interpolator can not only implement jerk-limited feedrate scheduling with critical points detection,but also realize self-switching of two interpolation modes.Finally,two patterns are machined with a carving platform based on ICMS.Experiment l results show the effectiveness of ICMS.

关键词： Bézier control polygon corner transition jerk-limited scheduling mixed interpolation pythagorean-hodograph curve

lifecycle carbon footprint and cost assessment for coal-to-liquid coupled with carbon capture,storage,and utilization technology in China

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Frontiers in Energy 2023年第3期17卷 412-427页

作者： Jingjing XIE Kai Li Jingli FAN Xueting PENG Jia li Yujiao XIAN Centre for Sustainable Development and Energy Policy Research School of Energy and Mining EngineeringChina University of Mining and TechnologyBeijing 100083China Centre for Sustainable Development and Energy Policy Research School of Energy and Mining EngineeringState Key Laboratory of Coal Resources and Safe MiningChina University of Mining and TechnologyBeijing 100083China The Administrative Centre for China's Agenda 21 Ministry of Science and TechnologyBeijing 100038China The Hong Kong University of Science and Technology(Guangzhou) Carbon Neutrality and Climate Change ThrustGuangzhou 511400China Jiangmen Laboratory of Carbon Science and Technology The Hong Kong University of Science and TechnologyJiangmen 529199China Centre for Sustainable Development and Energy Policy Research School of Energy and Mining EngineeringState Key Laboratory of Coal Resources and Safe MiningSchool of ManagementChina University of Mining and TechnologyBeijing 100083China

Thecoal-to-liquidcoupledwithcarbon capture,utilization,and storage technology has the potential to reduce CO_(2)emissions,but its carbon footprint and cost assessment are still insufficient.In this paper,coal mining to oil production is taken as a life cycle to evaluate the carbon footprint and levelized costs of direct-coal-toliquid and indirect-coal-to-liquid coupled with the carbon capture utilization and storage technology under three scenarios:non capture,process capture,process and public capture throughout the life cycle.The results show that,first,the coupling carbon capture utilization and storage technology can reduce CO_(2)footprint by 28%-57%from 5.91 t CO_(2)/t:oil of direct-coal-to-liquid and 24%-49%from 7.10 t CO_(2)/t:oil of indirect-coal-to-liquid.Next,the levelized cost of direct-coal-to-liquid is 648-1027$/t of oil,whereas that of indirect-coal-to-liquid is 653-1065$/t of oil.When coupled with the carbon capture utilization and storage technology,the levelized cost of direct-coalto-liquid is 285-1364$/t of oil,compared to 1101-9793/t of oil for indirect-coal-to-liquid.Finally,sensitivity analysis shows that CO_(2)transportation distance has the greatest impact on carbon footprint,while coal price and initial investment cost significantly affect the levelized cost ofcoal-to-liquid.

关键词： coal-to-liquid carbon capture utilization and storage(CCUS) carbon footprint levelized cost of liquid lifecycle assessment

CeO_(2)-supported Fe,Co and Ni toward CO_(2) hydrogenation:Tuning catalytic performance via metal-support interaction

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Journal of Rare Earths 2023年第6期41卷 926-932,I0005页

作者： Bolang li Fei Wang Kai Li Ping Ning Min Chen Changbin Zhang Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China National-Regional Engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming University of Science and TechnologyKunming 650500China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environment SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The chemical transformation of CO_(2) produces carbon compounds that can be used as precursors for the production of chemicals and fuels.Here,we investigated the activity and selectivity of the transition metals(Fe,Co,and Ni)supported on CeO_(2) catalyst for CO_(2) hydrogenation at atmospheric pressure.We found that Ni/CeO_(2) shows the highest CO_(2)conversion compared with Fe/CeO_(2) and Co/CeO_(2).Besides,Co/CeO_(2)and Ni/CeO_(2) exhibit nearly 100%CH_(4)selectivity while Fe/CeO_(2) inclines to produce CO.The characterization results show that the metal-support interaction order is Fe/CeO_(2)>Co/CeO_(2)>Ni/CeO_(2),the weak metal-support inte raction over Ni/CeO_(2)benefits the activation of H_(2) and then promotes the activity of CO_(2) hydrogenation.Additionally,in situ DRIFTS results demonstrate that monodentate formate species rather than bidentate formate are the active intermediates.The main route of CO_(2) hydrogenation to CH_(4) is that CO_(2) is firstly transformed to m-HCOO*and then direct hydrogenation of the m-HCOO*to CH_(4).This study provides insights into the understanding of the mechanisms of CO_(2) hydrogenation on CeO_(2)based catalysts.

关键词： Ni CeO_(2) Metal-support interaction CO_(2)hydrogenation Rare earths