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Rare Metals 2024年第2期43卷 624-634页

作者： xing-Yuan Zhang Mei-Na Lei Shan Tian Jian-Gan Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an710072China

High-energy-density li-S batteries are subjected to serious sulfur deactivation and short cycle lifetime caused by undesirable polysulfide shuttle effect and frantic lithium dendrite formation.In this work,a controllable cage-confinement strategy to fabricate molybdenum carbide(MoC)nanoclusters as a high-efficient sulfiphilic and lithiophilic regulator to mitigate the formidable issues of li-S batteries is demonstrated.The sub-2 nm MoC nanoclusters not only guarantee robust chemisorption and fast electrocatalytic conversion of polysulfides to enhance the sulfur electrochemistry,but also homogenize li^(+) flux to suppress the lithium dendrite growth.As a consequence,the MoC-modified separator endows the batteries with boosted reaction kinetics,promoted sulfur utilization,and improved cycling stability.A reversible capacity of 701 mAh·g^(−1) at a high rate of 5.0C and a small decay rate of 0.076%per cycle at 1.0C over 600 cycles are achieved.This study offers a rational route for design and synthesis of bifunctional nanoclusers with both sulfiphilicity and lithiophilicity for high-performance li-S batteries.

关键词： li-S batteries Nanocluster Electrocatalyst Polysulfide shuttle li dendrites

Predictors of portal vein thrombosis after splenectomy in patients with cirrhosis

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World Journal of Hepatology 2024年第2期16卷 241-250页

作者： Ting li li-li Wang ya-Ping li Jian Gan Xi-Sheng Wei Xiao-Rong Mao Jun-Feng li Department of Infectious Diseases The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710000Shaanxi ProvinceChina Department of Radiology First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Gastroenterology Yantai Affiliated Hospital of Binzhou Medical UniversityYantai 264100Shandong ProvinceChina Department of Infectious Diseases The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND Portal vein thrombosis(PVT)is a commonthsn complication after splenectomy in patients with cirrhosis.However,the predictors of postoperative PVT are not known.AIM To investigate the predictors of PVT after splenectomy in patient with cirrhosis.METHODS A total of 45 patients with cirrhosis who underwent splenectomy were consecutively enrolled from January 2017 to December 2018.The incidence of PVT at 1 months,3 months,and 12 months after splenectomy in patients with cirrhosis was observed.The hematological indicators,biochemical and coagulation parameters,and imaging features were recorded at baseline and at each observation point.The univariable,multivariable,receiver operating characteristic curve and timedependent curve analyses were performed.RESULTS The cumulative incidence of PVT was 40.0%,46.6%,and 48.9%at 1 months,3 months,and 12 months after splenectomy.Multivariable analysis showed that portal vein diameter(PVD)≥14.5 mm and monthsdel end-stage liver disease(MELD)score>10 were independent predictors of PVT at 1 months,3 months,and 12 months after splenectomy(P10(P10 were independent predictors of PVT at 1 months,3 months,and 12 months after splenectomy in patient with cirrhosis.

关键词： Cirrhosis Splenectomy Portal vein thrombosis Predictors

Three-dimensional choroidal vascularity index and choroidal thickness in fellow eyes of acute and chronic primary angle-closure using swept-source optical coherence tomography

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 42-52页

作者： Hai-li Huang Guan-Hong Wang liang-liang Niu xing-Huai Sun Department of Ophthalmology&Visual Science Eye&ENT HospitalShanghai Medical CollegeFudan UniversityShanghai 200031China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032China NHC Key Laboratory of Myopia Chinese Academy of Medical Sciencesand Shanghai Key Laboratory of Visual Impairment and Restoration(Fudan University)Shanghai 200031China

AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.

关键词： choroidal thickness choroidal vascularity index swept-source optical coherence tomography acute primary angle-closure chronic primary angle-closure glaucoma

Nicotinamide adenine dinucleotide phosphate oxidase in pancreatic diseases:Mechanisms and future perspectives

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World Journal of Gastroenterology 2024年第5期30卷 429-439页

作者： ya-Wei Bi Long-Song li Nan Ru Bo Zhang Xiao Lei Department of Gastroenterology The First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Radiation Oncology Chinese PLA General HospitalBeijing 100853China

Pancreatitis and pancreatic cancer(PC)stand as the most worrisome ailments affecting the pancreas.Researchers have dedicated efforts to unraveling the mechanisms underlying these diseases,yet their true nature continues to elude their grasp.Within this realm,oxidative stress is often believed to play a causal and contributory role in the development of pancreatitis and PC.Excessive accumulation of reactive oxygen species(ROS)can cause oxidative stress,and the key enzyme responsible for inducing ROS production in cells is nicotinamide adenine dinucleotide phosphate hydrogen oxides(NOX).NOX contribute to pancreatic fibrosis and inflammation by generating ROS that injure acinar cells,activate pancreatic stellate cells,and mediate macrophage polarization.Excessive ROS production occurs during malignant transformation and pancreatic carcinogenesis,creating an oxidative microenvironment that can cause abnormal apoptosis,epithelial to mesenchymal transition and genomic instability.Therefore,understanding the role of NOX in pancreatic diseases contributes to a more in-depth exploration of the exact pathogenesis of these diseases.In this review,we aim to summarize the potential roles of NOX and its mechanism in pancreatic disorders,aiming to provide novel insights into understanding the mechanisms underlying these diseases.

关键词： Nicotinamide adenine dinucleotide phosphate hydrogen oxides Pancreatitis Pancreatic cancer Reactive oxygen species Mechanism

The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang HUANG Weidong SUN xing DING Yusheng ZHAO Yibing li Xiuqi SHANG CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction zones.Silica is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly constrained.In this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal alteration.In experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and talc.The proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy analyses.Around 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much lower.The overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+2Talc.With the addition of more silica(20 wt%and 40 wt%),olivine was transformed into talc.The rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same period.The overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=2Talc.In experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal alteration.At 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen fugacity.Based on measured H_(2),we calibrated oxygen fugacities,ranging from 0.96 to 3.41 log un

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

Large-disturbance Stability Analysis of Power Systems with Synchronous Generator and Converter-interfaced Generation

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 997-1002页

作者： Lei Chen Yong Min liangshuai Hao Guangzheng xing yalou li Shiyun Xu IEEE Department of Electrical Engineering Tsinghua University China Electric Power Research Institute

This letter studies large-disturbance stability of the power system with a synchronous generator(SG) and a converter-interfaced generation(CIG) connected to infinite bus. The power system is multi-timescale and first simplified. It is shown that the boundary of region of attraction(ROA) of the simplified model is composed of stable manifolds of unstable equilibrium point(UEP) or semi-singular point(SSP), named anchor points, and singular surface pieces. The type of anchor point determines the dominant instability pattern of the power system. When the anchor point is UEP or SSP, the dominant instability pattern is the instability of rotor angle of SG or the instability of phase-locked loop and outer control loop(OCL) of CIG, respectively. Transition of dominant instability pattern can be analyzed with the relative position relationship between UEP and SSP. The effect of OCL is discussed. When the OCL is activated, the ROA becomes smaller and the system is more prone to instability of CIG. It is necessary to consider the OCL when studying the large-disturbance stability of the power system.

关键词： Power system stability Mathematical models Phase locked loops Stability criteria Transient analysis Power system dynamics Rotors

How incubation temperature affects hatchling performance in reptiles: an integrative insight based on plasticity in metabolic enzyme

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Current Zoology 2024年第2期70卷 195-203页

作者： Dan-yang Wu xing-Zhi Han Teng li Bao-Jun Sun Xiao-yan Qin College of life and Environment Sciences Minzu University of ChinaBeijing 100081China Key Laboratory of Animal Ecology and Conservational Biology Institute of ZoologyChinese Academy of SciencesBeijing 10011China College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China

Evaluating the effects of temperature variations on animals plays an important role in understanding the threat of climate warming.The effects of developmental temperature on offspring performance are critical in evaluating the effects of warming temperatures on the fitness of ovipa-rous species,but the physiological and biochemical basis of this developmental plasticity is largely unknown.In this study,we incubated eggs of the turtle Pelodiscus sinensis at low(24℃),medium(28℃),and high(32℃)temperatures,and evaluated the effects of developmental temperature on offspring fitness,and metabolic enzymes in the neck and limb muscles of hatchlings.The hatchlings from eggs incubated at the medium temperature showed better fitness-related performance(righting response and swimming capacity)and higher activities of metabolic enzymes(hexokinase,HK;lactate dehydrogenase,LDH)than hatchlings from the eggs incubated at high or low temperatures.In addition,the swimming speed and righting response were significantly correlated with the HK activities in limb(swimming speed)and neck(righting response)muscles,suggesting that the developmental plasticity of energy metabolic pathway might play a role in determining the way incubation temperature affects offspring phenotypes.Integrating the fitness-related performance and the activities of metabolic enzymes,we predict that the P sinensis from high latitude would not face the detrimental effects of climate warming until the average nest temperatures reach 32℃.

关键词： developmental plasticity energetic metabolism enzyme activity hatchling turtle.

Numerical investigation on thermomechanical behavior of alumina–calcium hexaluminate refractories for purging plug

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Journal of Iron and Steel Research(International) 2024年第2期31卷 389-400页

作者： li-ping Pan ya-wei li Fang-guan Tan Yi-chen Chen yang-fan Xu Zhu He Bao-kuan li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and lining Technology Wuhan University of Science and TechnologyWuhan430081HubeiChina

Alumina–spinel refractories used in slit-type purging plugs are susceptible to cross-sectional damage,resulting in a serious mismatch between their service life and that of ladle.Alumina–calcium hexaluminate refractories have gradually become the new trend in purging plug materials with the development of refining technology.The thermomechanical damage of slit-type purging plugs with alumina–calcium hexaluminate refractory was investigated by the thermo-solid coupling simulation.Combined with the polynomial fitting and design of experiments methods,the influence of thermophysical parameters on temperature and thermal stress of alumina–calcium hexaluminate refractories for purging plugs was systematically analyzed.The results show that the maximum thermal stress of the purging plugs appears during the stages of steel transporting and stirring,and the vulnerable parts are located above Y=0.323 m.The thermal conductivity and the coefficient of thermal expansion of the material are the most sensitive parameters to the temperature and thermal stress inside the structure,respectively.The addition of more calcium hexaluminate can relieve the stress concentration and large deformation around the slits.Consequently,when the content of calcium hexaluminate is 47 wt.%and in the form of aggregate-binder,the temperature and thermal stress distribution inside the refractory are optimal,which can effectively improve the service life of the slit-type purging plug.

关键词： Purging plug Thermomechanical damage Refractory Design of experiments method Stress

Pollution source identification methods and remediation technologies of groundwater: A review

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China Geology 2024年第1期7卷 125-137页

作者： ya-ci liu Yu-hong Fei ya-song li Xi-lin Bao Peng-wei Zhang Fujian Provincial Key Laboratory of Water Cycling and Eco-Geological Processes Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesXiamen 361000China Key Laboratory of Water and Soil Resources Conservation and Restoration in the Middle and Lower Reaches of Yellow River Basin MNRZhengzhou 450016China

Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.

关键词： Groundwater pollution Identification of pollution sources Geophysical exploration identification Geochemistry identification Isotopic tracing Numerical modeling Remediation technology Hydrogeological conditions Hydrogeological survey engineering

The Complete Classification of Graphs whose Second Largest Eigenvalue of the Eccentricity Matrix is Less Than 1

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1741-1766页

作者： Jian Feng WANG xing Yu LEI Shu Chao li Zoran STANIC School of Mathematics and Statistics Shandong University of TechnologyZibo255049P.R.China Faculty of Mathematics and Statistics Central China Normal UniversityWuhan430079P.R.China Faculty of Mathematics University of BelgradeStudentski trg 1611000BelgradeSerbia

The eccentricity matrix of a graph is obtained from the distance matrix by keeping the entries that are largest in their row or column,and replacing the remaining entries by zero.This matrix can be interpreted as an opposite to the adjacency matrix,which is on the contrary obtained from the distance matrix by keeping only the entries equal to 1.In the paper,we determine graphs having the second largest eigenvalue of eccentricity matrix less than 1.

关键词： Eccentricity matrix eigenvalue diameter principal submatrix forbidden subgraph