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Study on hydrodynamic diffusion law of the swelling particle slurry in karst pipeline

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Particuology 2024年第4期87卷 218-231页

作者： Bingchuan Cheng Haibo Li Guangming Pan Runhuai Deng Yu'an Gong Shujun Xu Kun Zhou Zhuo Zheng School of Civil Engineering Geotechnical and Structural Engineering Research CenterShandong UniversityJinan250061China The Fourth Prospecting of Shandong Coal Geology Bureau Weifang261000China china Railway 14th Bureau Group Corporation Limited Jinan250101China School of Trafic Engineering Shandong Jianzhu University.Fengming RoadLingang Development ZoneJinan250101China

The swelling particle grouting material has demonstrated remarkable plugging effectiveness in high-pressure and large-flow burst water within karst pipelines.Currently,current research on the rheolog-ical model,flow computation theory,and plugging mechanism of this material is lacking.The conven-tional grouting slurry diffusion process,using the liquid-liquid two-phase flow method,fails to accurately simulate high solubility slurry and particle swelling.To address these limitations,this study established a precise constitutive model to describe the swelling particle slurry diffusion process in dynamic water.Additionally,a coupling calculation method was proposed to analyze the spatiotemporal heterogeneity of viscosity during slurry diffusion by considering the migration of slurry and the changes in viscosity.To investigate the interaction between particle swelling and flow field changes,a Compu-tational Fluid Dynamics-Discrete Element Method(CFD-DEM)coupling model was developed for the diffusion of swelling particle slurry.It is demonstrated that slurry viscosity increases exponentially within the diffusion front as the particle swelling rate rises,and the drag force exhibits an intriguing behavior of initially increasing and then decreasing as the slurry flows through the pipeline.Further-more,the CFD-DEM coupling model proved to be more accurate in describing viscosity distribution and diffusion distance compared to the finite element solution.The primary objective of this paper is to reveal the plugging mechanism and provide theoretical support for the engineering application of the swelling particle grouting material.

关键词： Karst pipeline Swelling particle grouting material Dynamic water diffusion Spatiotemporal variation of viscosity CFD-DEM coupling model

Spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in china’s cities

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 74-86页

作者： Ruyu Xu Keliang Wang Zhuang Miao Lingxuan Sun School of Economics Ocean University of ChinaQingdao 266011China china Western Economic Research center Southwestern University of Finance and EconomicsChengdu 611130China School of Economics and management Southwest Petroleum UniversityChengdu 610500China

The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)methods.The findings are:①china’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder china’s urban EE.③Four configurational promotion paths for enhancing china’s urban EE are identified,where among those paths population density is a core condition,while government intervention is not.This study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in china.

关键词： Energy efficiency Spatiotemporal variations Influencing factors Configurational promotion paths

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Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and development Base Harbin Engineering University Qingdao Innovation and development center Harbin Engineering University CNOOC Research Institute Co. Ltd. College of Marine Geoscience Ocean University of China Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.

The low-wavenumber components in the gradient of full waveform inversion(FWI) play a vital role in the stability of the inversion. However, when FWI is implemented in some high frequencies and current models are not far away from the real velocity model, an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion accuracy. To solve this problem, this paper firstly derives a formula of scattering angle weighted gradient in FWI, then proposes a hybrid gradient. The hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived herein.Using weighted hybrid mode, we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion, and use more high-wavenumber components in the high-frequency inversion to improve the convergence rate. The results of synthetic data experiment demonstrate that compared to the conventional FWI, the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion stability. It also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the model. And the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI) has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Cognitive impairment in cerebral small vessel disease induced by hypertension

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Neural Regeneration Research 2024年第7期19卷 1454-1462页

作者： Weipeng Wei Denglei Ma Lin Li Lan Zhang Department of Pharmacy Xuanwu Hospital of Capital Medical UniversityBeijingChina Beijing Geriatric Medical Research center Beijing Engineering Research Center for Nervous System DrugsNational Center for Neurological DisordersNational Clinical Research Center for Geriatric DiseasesBeijingChina

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension and cerebral small vessel disease remains unclear.Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease.Chronic hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and stroke.Hypertension is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of hypertension.This review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive ability.We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

关键词： blood-brain barrier cerebral small vessel disease cognitive impairment dementia endothelial dysfunction enlarged perivascular space hypertension lacunar infarction neuroinflammation treatment white matter high signal intensity

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Assessment of climate damage in china based on integrated assessment framework

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Advances in Climate Change Research 2024年第1期15卷 124-133页

作者： Jie LIU Xiang-Zhen SHI Li YANG Chang-Yi LIU Jin-Cheng WANG Rui-Min ZHU Xue-Li SHI Qiu-Feng LIU International Business School Shanxi Normal UniversityXi'an 710062China University of Chinese Academy of Social Sciences Bejing 102488China School of Economics and management Xinjiang UniversityUrumqi 830046China Global Energy Interconnection development and Cooperation Organization(GEIDCO) Bejing 100031China Hubei Enshi College Enshi 445099China CMA Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081China National Climate Centre China Meteorological AdministrationBeijing 100081China

Developing a localized and consistent model framework for climate loss and damage assessment is crucial for the policy-making of climate change mitigation and adaptation.This study introduces a comprehensive,multidisciplinary Integrated Assessment Model(IAM)framework for evaluating climate damage in china,utilizing BCC-SESM climate model and fund sectoral climate damage model under the SSP2-RCPs scenario.Employing a bottom-up approach,the research estimates climate damage across eight major sectors,recalibrates sectoral climate damage functions and parameters for china,and elucidates distinctions among direct climate loss,market climate loss,and aggregate climate loss.The findings reveal that the total climate damage function for china follows a quadratic pattern in response to temperature rise.By 2050,the estimated climate damage is projected to be 5.4%,5.7%,and 8.2%of GDP under RCP2.6,RCP4.5,and RCP8.5,respectively.Additionally,both direct and market climate losses are projected to remain below 2%of GDP by 2050,while the aggregate climate loss could reach as high as 8.2%,which is predominantly attributed to non-market sectors.From a sectoral perspective,under the RCP8.5 scenario,human health damage constitutes the largest share(61.9%)of the total climate loss by 2050,followed by sea-level rise damage(18.6%).This study sheds lights on the adaptation policy that should attach importance to the non-market sectors,particularly focusing on human health and sea-level rise.

关键词： Climate loss and damage Integrated assessment model(IAM) fund model Representative concentration pathways(RCPs)scenario BCC-SESM

Nanotechnology’s frontier in combatting infectious and inflammatory diseases:prevention and treatment

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Signal Transduction and Targeted Therapy 2024年第3期9卷 998-1047页

作者： Yujing Huang Xiaohan Guo Yi Wu Xingyu Chen Lixiang Feng Na Xie Guobo Shen Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China Hospitaland West China School of Basic Medical Sciences and Forensic MedicineSichuan Universityand Collaborative Innovation Center for BiotherapyChengdu 610041China

Inflammation-associated diseases encompass a range of infectious diseases and non-infectious inflammatory diseases,which continuously pose one of the most serious threats to human health,attributed to factors such as the emergence of new pathogens,increasing drug resistance,changes in living environments and lifestyles,and the aging population.Despite rapid advancements in mechanistic research and drug development for these diseases,current treatments often have limited efficacy and notable side effects,necessitating the development of more effective and targeted anti-inflammatory therapies.In recent years,the rapid development of nanotechnology has provided crucial technological support for the prevention,treatment,and detection of inflammation-associated diseases.Various types of nanoparticles(NPs)play significant roles,serving as vaccine vehicles to enhance immunogenicity and as drug carriers to improve targeting and bioavailability.NPs can also directly combat pathogens and inflammation.In addition,nanotechnology has facilitated the development of biosensors for pathogen detection and imaging techniques for inflammatory diseases.This review categorizes and characterizes different types of NPs,summarizes their applications in the prevention,treatment,and detection of infectious and inflammatory diseases.It also discusses the challenges associated with clinical translation in this field and explores the latest developments and prospects.In conclusion,nanotechnology opens up new possibilities for the comprehensive management of infectious and inflammatory diseases.

关键词： prevention inflammatory treatment

Application of controlled-release urea increases maize N uptake,environmental benefits and economic returns via optimizing temporal and spatial distributions of soil mineral N

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Pedosphere 2024年第1期34卷 222-235页

作者： Mingxue SUN Juan LI Lili ZHANG Xiaomeng SU Ning LIU Xiaori HAN Songjiang WU Zhentao SUN Xiangdong YANG Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Key Laboratory of Plant Nutrition and FertilizerMinistry of Agriculture and Rural AffairsBeijing 100081China Agricultural development Service center of Zhuanghe Zhuanghe 116499China Agricultural Technology Extension center Wafangdian 116300China College of Land and Environment Shenyang Agricultural UniversityShenyang 100866China

The creation of controlled-release urea (CRU) is a potent substitute for conventional fertilizers in order to preserve the availability of nitrogen (N) in soil,prevent environmental pollution,and move toward green agriculture.The main objectives of this study were to assess the impacts of CRU’s full application on maize production and to clarify the connection between the nutrient release pattern of CRU and maize nutrient uptake.In order to learn more about the effects of CRU application on maize yields,N uptake,mineral N (N_(min)) dynamics,N balance in soil-crop systems,and economic returns,a series of field experiments were carried out in 2018–2020 in Dalian City,Liaoning Province,china.There were 4 different treatments in the experiments:no N fertilizer input (control,CK);application of common urea at 210 kg ha^(-1)(U),the ideal fertilization management level for the study site;application of polyurethane-coated urea at the same N input rate as U (PCU);and application of PCU at a 20% reduction in N input rate (0.8PCU).Our findings showed that using CRU (i.e.,PCU and 0.8 PCU) may considerably increase maize N absorption,maintain maize yields,and increase N use efficiency (NUE) compared to U.The grain yield showed considerable positive correlations with total N uptake in leaf in U and 0.8 PCU,but negative correlations with that in PCU,indicating that PCU caused excessive maize absorption while 0.8 PCU could achieve a better yield response to N supply.Besides,PCU was able to maintain N fertilizer in the soil profile 0–20 cm away from the fertilization point,and higher N_(min)content was observed in the 0–20 cm soil layer at various growth stages,particularly at the middle and late growing stages,optimizing the temporal and spatial distributions of N_(min).Additionally,compared to that in U,the apparent N loss rate in PCU was reduced by 36.2%,and applying CRU (PCU and 0.8 PCU) increased net profit by 8.5% to 15.2% with less labor and fertilization frequency.It was concluded that using CRU could be an effective N f

关键词： apparent N loss fertilization management green agriculture maize yield N balance N use efficiency

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A strategy to synthesize phosphorus-containing nickel phyllosilicate whiskers to enhance the flame retardancy of epoxy composites with excellent mechanical and dry-friction properties

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 39-50页

作者： Shibin Nie Zongquan Zhao Yuxuan Xu Wei He Wenli Zhai Jinian Yang School of Public Security and Emergency management Anhui University of Science and TechnologyHefei231131China School of Safety Science and Engineering Anhui University of Science and TechnologyHuainan232001China School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan232001China Institute of Energy Hefei Comprehensive National Science CenterHefei230000China

To enhance the fire safety and wear resistance of epoxy,phosphorus-containing nickel phyllosilicate whiskers(FP-NiPS)were synthesized using a facile hydrothermal technology,with 9,10-dihydro-9-oxa-10-phosphaphenanthrene as the organic modifier.The impacts of FP-NiPS on the thermal stability,flame retardancy,and mechanical and tribological properties of EP composites were explored.The findings demonstrated that 5 wt%FP-NiPS elevated the limiting oxygen index of the EP composite from 23.8%to 28.4%,achieving a V-0 rating during vertical burning tests.FP-NiPS could enhance the thermal stability of epoxy resin(EP)and facilitate the development of a dense and continuous carbon layer,thereby significantly improving the fire safety of the EP composites.The FP-NiPS led to an 8.2%increase in the tensile strength and a 38.8%increase in the elastic modulus of the EP composite,showing outstanding mechanical properties.Furthermore,FP-NiPS showed remarkable potential in enhancing the wear resistance of EP.The wear rate of 1 wt%FP-NiPS is 2.34×10^(−5) mm^(3)·N^(−1)·m^(−1),a decrease of 66.7%compared to EP.This work provides a novel promising modification method to enhance the fire safety,mechanical and wear resistance properties of EP.

关键词： nickel phyllosilicate epoxy resin flame retardant wear resistance mechanical property

Plasma Metabonomics of Human Adenovirus-infected Patients with Pneumonia and Upper Respiratory Tract Infection

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Current Medical Science 2024年第1期44卷 121-133页

作者： Ting-ting WEI Wen XU Bo TU Wan-xue ZHANG Xin-xin YANG Yiguo ZHOU Shan-shan ZHANG Jun-lian YANG Ming-zhu XIE Juan DU Wei-wei CHEN Qing-bin LU Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Infectious Disease The Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Department of Laboratorial Science and Technology&Vaccine Research center School of Public HealthPeking UniversityBeijing 100191China Department of Health Policy and management School of Public HealthPeking UniversityBeijing 100191China Global center for Infectious Disease and Policy Research&Global Health and Infectious Diseases Group Peking UniversityBeijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China

Objective Human adenovirus(HAdV)infection is common and can develop to serious conditions with high mortality,yet the mechanism of HAdV infection remains unclear.In the present study,the serum metabolite profiles of HAdV-7-infected patients with pneumonia or upper respiratory tract infection(URTI)were explored.Methods In total,35 patients were enrolled in the study following an outbreak of HAdV-7 in the army,of whom 14 had pneumonia and 21 had URTI.Blood samples were collected at the acute stage and at the recovery stage and were analyzed by untargeted metabolomics.Results Over 90% of the differential metabolites identified between the pneumonia patients and URTI patients were lipids and lipid-like molecules,including glycerophospholipids,fatty acyls,and sphingolipids.The metabolic pathways that were significantly enriched were primarily the lipid metabolism pathways,including sphingolipid metabolism,glycerophospholipid metabolism,and linoleic acid metabolism.The sphingolipid metabolism was identified as a significantly differential pathway between the pneumonia patients and URTI patients and between the acute and recovery stages for the pneumonia patients,but not between the acute and recovery stages for the URTI patients.Ceramide and lactosylceramide,involved in sphingolipid metabolism,were significantly higher in the pneumonia patients than in the URTI patients with good discrimination abilities[area under curve(AUC)0.742 and 0.716,respectively;combination AUC 0.801].Conclusion Our results suggested that HAdV modulated lipid metabolism for both the patients with URTI and pneumonia,especially the sphingolipid metabolism involving ceramide and lactosylceramide,which might thus be a potential intervention target in the treatment of HAdV infection.

关键词： human adenovirus metabonomic lipids pneumonia upper respiratory tract infection