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Reconstruction of phytoplankton productivity and community structure in the South Yellow Sea

China Geology 2019年第3期2卷 315-324页

作者： Xi Mei ri-hui li Xun-hua Zhang Zhong-bo Wang Yong Zhang Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceangraphyMinistry of Natural ResourcesQingdao 266061China

The sedimentary environment and ecological system in the South Yellow Sea (SYS) changed dramatically due to sea level change caused by glacial-interglacial cycles. The authors report the use of marine biomarkers (brassicasterol, dinosterol and C37 alkenones) and terrigenous biomarkers (C28+C30+C32 nalkanols) in core DLC70-3 from the SYS to reconstruct the variation in the phytoplankton productivity and community structure and possible mechanisms during the middle Pleistocene. The results show that the primary productivity and that of single algae presented a consistent trend for the whole core during the middle Pleistocene, which was high during interglacial periods and low during glacial periods, with the highest being in marine isotope stage (MIS) 5–9 and MIS 19–21. The main reason is that the Yellow Sea Warm Current (YSWC) carried much of high temperature, high salinity water into the SYS, causing upwelling and vertical mixing and stirring, which increased the nutrient supply in the photosynthetic layer. The phytoplankton community structure mainly showed an increase in the relative content of haptophytes in MIS 5–9 and MIS 19–21, while the relative content of diatoms and dinoflagellates decreased;there was no evidence for a haptophyte content in other stages. The results reveal a shift from a coccolitho-phoriddominated community during MIS 5 –9 and MIS 19 –21 to a diatom-dominated community during the other stages, mainly as a result of surface salinity variation, attributed to the invasion of the YSWC during high sea level periods.

关键词： Biomarker Phytoplankton productivity Phytoplankton community Ocean warm current Global climate change Marine geological survey engineering Yellow Sea China

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Influence of indoor airflow on airborne disease transmission in a classroom

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Building Simulation 2024年第3期17卷 355-370页

作者： Mojtaba Zabihi ri li Joshua Brinkerhoff School of Engineering Faculty of Applied ScienceUniversity of British ColumbiaKelownaCanada

It has been widely accepted that the most effective way to mitigate airborne disease transmission in an indoor space is to increase the ventilation airflow,measured in air change per hour(ACH).However,increasing ACH did not effectively prevent the spread of *** better understand the role of ACH and airflow large-scale patterns,a comprehensive fully transient computational fluid dynamics(CFD)simulation of two-phase flows based on a discrete phase model(DPM)was performed in a university classroom setting with people *** investigations encompass various particle sizes,ventilation layouts,and flow *** findings demonstrated that the particle size threshold at which particles are deemed airborne is highly influenced by the background flow strength and large-scale flow pattern,ranging from 5µm to 10µm in the cases *** effects of occupants are significant and must be precisely accounted for in respiratory particle transport *** enhanced ventilation design(UFAD-CDR)for university classrooms is introduced that places a premium on mitigating airborne disease *** to the baseline design at the same ACH,this design successfully reduced the maximum number density of respiratory particles by up to 85%.A novel airflow-related parameter,Horizontality,is introduced to quantify and connect the large-scale airflow pattern with indoor aerosol *** underscores that ACH alone cannot ensure or regulate air *** addition to the necessary ACH for air exchange,minimizing horizontal bulk motion is essential for reducing aerosol transmissibility within the room.

关键词： aerosol transmission airflow pattern horizontality COVID-19 simulation classroom ventilation

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Pre-operative enhanced magnetic resonance imaging combined with clinical features predict early recurrence of hepatocellular carcinoma after radical resection

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1192-1203页

作者： Jian-Ping Chen ri-hui Yang Tian-hui Zhang li-An liao Yu-Ting Guan Hai-Yang Dai Department of Intervention Meizhou People’s HospitalMeizhou 514031Guangdong ProvinceChina Department of Medical Imaging Meizhou People’s HospitalMeizhou 514031Guangdong ProvinceChina Department of Medical Imaging Huizhou Municipal Central HospitalHuizhou 516001Guangdong ProvinceChina

BACKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(HCC)has great significance for patient *** To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(Mri)combined with clinical features in predicting early recurrence of HCC after *** A total of 161 patients with pathologically confirmed HCC were *** patients were divided into early recurrence and non-early recurrence group based on the follow-up *** clinical,laboratory,pathological results and Gd-EOB-DTPA enhanced Mri imaging features were *** Of 161 patients,73 had early recurrence and 88 were had non-early *** analysis showed that patient age,gender,serum alpha-fetoprotein level,the Barcelona Clinic liver Cancer stage,China liver cancer(CNLC)stage,microvascular invasion(MVI),pathological satellite focus,tumor size,tumor number,tumor boundary,tumor capsule,intratumoral necrosis,portal vein tumor thrombus,large vessel invasion,nonperipheral washout,peritumoral enhancement,hepatobiliary phase(HBP)/tumor signal intensity(SI)/peritumoral SI,HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of HCC after *** logistic regression analysis showed that patient age,MVI,CNLC stage,tumor boundary and large vessel invasion were independent predictive *** data validation indicated that the area under the curve of the combined predictors was 0.861,suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of *** Gd-EOB-DTPA enhanced Mri combined with clinical features would help predicting the early recurrence of HCC after operation.

关键词： Hepatocellular carcinoma Enhanced magnetic resonance imaging Microvascular invasion Hepatobiliary phase Recurrence

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Comparison of detrital mineral compositions between stream sediments of the Yangtze river (Changjiang) and the Yellow river (Huanghe) and their provenance implication

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China Geology 2019年第2期2卷 169-178页

作者： Zhong-bo Wang ri-hui li Shou-ye Yang Feng-long Bai Xi Mei Jian Zhang Kai Lu Qingdao Institute of Marine Geology China Geological SurveyMinisitry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

A comparative comparative study on the detrital mineral composition of stream sediments of the Yangtze river (Changjiang) and Yellow river (Huanghe) shows that, light minerals of the Yangtze river basin were mainly quartz, feldspar, and detritus, the compositional characteristics of light minerals differed among tributaries, the main stream had a generally higher maturity index than tributaries;heavy mineral content tended to decrease progressively from the upper stream to lower stream of the Yangtze river, the primary assemblage was magnetite-hornblende-augite-garnet-epidote, and diagnostic minerals of different river basins were capable of indicating the nature and distribution of the source rock. Detrital mineral assemblages in sediments of tributaries and the main stream of the Yellow river were basically similar, Primary heavy mineral assemblage was opaque mineral-garnet-epidote-carbonate mineral and alteration mineral. Variations in the contents of garnet, opaque mineral, and hornblende mainly reflected the degree of sedimentary differentiation in suspended sediment and the hydrodynamic intensity of a drainage system. The heavy mineral differentiation index F revealed sedimentary differentiation of diagnostic detrital mineral composition due to changes in regional hydrodynamic intensity and can serve as an indicator for studying the dynamic sedimentary environment of a single-provenance river and the degree of sedimentary differentiation of its detrital minerals. Changes in detrital mineral content of the Yellow river was not completely controlled by provenance but reflected gravity sorting of the detrital mineral due to variations in the ephemeral river hydrodynamic intensity and sedimentary environment, however the index changing of Yangtze river were mainly influenced by the complex sediment sources. Therefore caution must be exercised in using the detrital mineral composition of marginal sea to determine the contribution of the Yangtze river and Yellow riv

关键词： Yangtze river Yellow river Sediment Detrital mineral Provenance implication

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Synthesis of granulated li_(1.33)Mn_(1.67)O_(4) via two antisolvent methods for lithium adsorption from gas-produced water

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Chinese Journal of Chemical Engineering 2024年第5期69卷 34-46页

作者： Jun Qiu Lu-ri Bao Wei Guo Ying Yang Shu-Ying Sun National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China

Gas-produced water is an accompanying wastewater in the natural gas extraction process,and it is a potential liquid lithium resource that contains a considerable amount of *** study investigated the feasibility of using manganese-based ion sieves to adsorb and extract lithium from gas-produced *** we focused on the applicability of two different granulation methods,extrusion and droplet,in gas-produced water *** types of H_(1.33)Mn_(1.67)O_(4) particles were prepared by the extrusion method(EHMO)and the droplet method(DHMO).The porosity of DHMO was much higher than that of EHMO,and the adsorption performance of DHMO increased with the decrease of binder *** prepared with a binder concentration of 0.14 g·ml^(-1)exhibited the best adsorption performance in gas-produced water,and the li^(+)adsorption capacity could reach 25.14 mg·g^(-1).In gas-produced water,the adsorption equilibrium of DHMO only took 9 h,and the adsorption process conformed to the Langmuir model and pseudo-second-order kinetic *** pore diffusion model(PDM)could well describe its adsorption ***,DHMO showed a great selectivity to li^(+),and the selectivity order of DHMO in gas-produced water was li^(+)>Ba^(2+)>>Mg^(2+),Ca^(2+),Sr^(2+)>>Na^(+)>>K^(+).After 20 cycles,the li^(+)adsorption capacity was still higher than 17.30 mg·g^(-1),and the rate of manganese dissolution was less than 1%.

关键词： Gas-produced water Granulation li_(1.33)Mn_(1.67)O_(4)

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Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-Wen Lu hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan Wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

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Higher-order expansions of powered extremes of logarithmic general error distribution

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 47-54页

作者： TAN Xiao-feng li li-hui School of Mathematics and Statistics Southwest UniversityChongqing 400715China

In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥***-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing *** is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v).

关键词： logarithmic general error distribution convergence rate higher-order expansion powered ex-treme

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Prescribed-time stabilization and inverse optimal control of stochastic high-order nonlinear systems

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Science China(Information Sciences) 2024年第2期67卷 144-156页

作者： Ran liU hui WANG Wuquan li School of Mathematics and Statistics Science Ludong University

This paper investigates the prescribed-time state-feedback stabilization and prescribed-time inverse optimality problems for stochastic high-order nonlinear systems. First, a time-varying controller is designed by developing scaled quartic Lyapunov functions, which can guarantee that the system has a unique strong solution almost surely on the prescribed interval for any system initial conditions and that the states and the control converge to the origin in a mean-square form within the prescribed time. Then, the controller is redesigned to address the problem of prescribed-time inverse optimal mean-square stabilization. Finally,a concrete example is provided to confirm the efficiency of the proposed design schemes.

关键词： stochastic high-order nonlinear systems prescribed-time stabilization the scaled design inverse optimality

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Role of outdoor trees on pedestrian wind and thermal conditions around a pre-education building for sustainable energy management

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Journal of Central South University 2024年第6期31卷 2039-2053页

作者： li Xiao-jie TANG hui-li Zhengzhou Preschool Education College Zhengzhou 450000China

Finding sustainable energy resources is essential to face the increasing energy *** are an important part of ancient architecture but are becoming rare in urban *** can control and tune the pedestrian-level wind velocity and thermal *** this study,a numerical investigation is employed to assess the role of trees planted in the windward direction of the building complex on the thermal and pedestrian wind velocity conditions around/inside a pre-education building located in the center of the *** to the previous studies(which considered only outside buildings),this work considers the effects of trees on microclimate change both inside/outside *** of different parameters including the leaf area density and number of trees,number of rows,far-field velocity magnitude,and thermal condition around the main building are *** results show that the flow velocity in the spacing between the first-row buildings is reduced by 30%-40% when the one-row trees with 2 m height are planted 15 m farther than the ***,two rows of trees are more effective in higher velocities and reduce the maximum velocity by about 50%.The investigation shows that trees also could reduce the temperature by about 1℃around the building.

关键词： sustainable management energy trees urban area thermal condition building

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Optimizing piezoelectric performance of complex perovskite through increasing diversity of B-site cations

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Journal of Materials Science & Technology 2024年第3期170卷 78-86页

作者： Mengdi Cheng Dongyan Zhang Yangxi Yan Zhimin li Pangpang Wang ri-ichi Murakami School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China Nanomaterials Group Institute of SystemInformation Technologies and Nanotechnologies(ISIT)Fukuoka Industry-Academia Symphonicity(FiaS)4-1 KyudaishinmachiNishi-kuFukuoka 819-0388Japan School of Mechanical Engineering Chengdu UniversityChengdu 610106China

Piezoelectric materials with unique properties are hugely appealing for high sensitivity sensors and ultrasonic ***,Pb(Ni_(1/3)Nb_(2/3))O_(3)-Pb(Yb_(1/2)Nb_(1/2))O_(3)-PbTiO_(3)piezoelectric system was designed and investigated in *** optimized piezoelectric response(d_(33)=826 pC/N,d_(33)∗=1017 pm/V)together with good temperature stability and negligible performance degradation up to 10^(6) cycles was achieved in 0.58PNN-0.10PYN-0.32PT *** analysis revealed the amplification of intrinsic and extrinsic contributions in MPB region due to more spontaneous polarization orientations and an increase in chemical disorder of system after the introduction of *** origin of high piezoelectric response was investigated through the combination of scanning electron microscopy and piezoresponse force *** diversity of B-site cations was shown to enhance local structural heterogeneity,weaken long-range ferroelectric ordered domains,and lower free energy barrier via the formation of nanodomain configuration that promoted polarization rotation,thereby improving piezoelectric properties of the ***,it is suggested that increasing the diversity of B-site cations is an effective strategy for achieving outstanding piezoelectric performance.

关键词： PNN-PYN-PT ceramics Piezoelectricity enhancement Relaxation behavior Domain structure

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