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Numerical Simulation of the Mass Movement Process of the 2018 Sedongpu Glacial Debris Flow by Using the Fluid-Solid Coupling Method

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Journal of Earth Science 2024年第2期35卷 583-596页

作者： Xing-Yu Long Yu-Xiang Hu Bin-Rui Gan jia-wen zhou State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China College of Water Resource and Hydropower Sichuan UniversityChengdu610065China

In the context of global warming and intensified human activities,glacier instability in plateau regions has increased,and glacier debris flows have become active,which poses a significant threat to the lives and property of people and socioeconomic *** mass movement process of glacier debris flows is extremely complex,so this paper uses the 2018 Sedongpu glacier debris flow event on the Qinghai-Tibet Plateau as an example and applies a numerical simulation method to invert the whole process of mass *** view of the interaction between phases in the process of motion,we use the fluid-solid coupling method to describe the mass *** granular-flow model and drift-flux model are employed in FLOW3D software to study the mass movement process of glacier debris flows and explore their dynamic *** results indicate that the glacier debris flow lasted for 700 s,and the movement process was roughly divided into four stages,including initiation,scraping,surging and deposition;the depositional characteristics calculated by the fluid-solid coupling model are consistent with the actual survey results and have good reliability;strong erosion occurs during the mass movement,the clear volume amplification effect,and the first wave climbs 17.8 m across the *** fluid-solid coupling method can better simulate glacier debris flows in plateau regions,which is helpful for the study of the mechanism and dynamic characteristics of such disasters.

关键词： glacial debris flow Qinghai-Tibet Plateau fluid-solid coupling FLOW3D mass movement depositional characteristics disasters engineering geology

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Percutaneous kyphoplasty in the treatment of Kümmell disease in lumbar scoliosis:A case report

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World Journal of Clinical Cases 2024年第17期12卷 3123-3129页

作者： Saijilafu jia-wen zhou Gen-Lin Wang Ke-Hong Sun Ji-Le Xie Department of Orthopaedic Surgery Hangzhou Lin’an Traditional Chinese Medicine HospitalAffiliated HospitalHangzhou City UniversityHangzhou 311300Zhejiang ProvinceChina Department of Orthopaedic Surgery The First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

BACKGROUND Due to mechanical imbalance in the spine,elderly scoliosis patients tend to develop vertebral fracture nonunion,i.e.,Kümmell disease,when osteoporotic vertebral compression fractures ***,accompanying vertebral rotational deformities make surgical procedures challenging *** patients are usually compelled to undergo conservative treatment and there are very few reports on minimally invasive surgeries for *** first-time report a patient with Kümmell disease and lumbar scoliosis treated with percutaneous kyphoplasty(PKP)under O-arm *** SUMMARY An 89-year-old female was admitted to the hospital due to delayed low back pain after a *** was diagnosed with Kümmell disease based on physical and radiologic *** patient experienced severe scoliosis and subsequently underwent O-arm-guided kyphoplasty,resulting in a significant alleviation of low back *** PKP has good efficacy in treating Kümmell ***,surgical risks are elevated in scoliosis patients with Kümmell disease due to the abnormal anatomical structure of the spine.O-arm assisted operations play a crucial role in decreasing surgical risks.

关键词： Kümmell disease Vertebral compression fracture Scoliosis Kyphoplasty Case report

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Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis

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Science China Chemistry 2024年第11期67卷 3807-3816页

作者： wen-Yuan Qu Xue-Song zhou wen-Jing Xiao jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of Chemistry Central China Normal University Wuhan Institute of Photochemistry and Technology Key Laboratory of Organo-Pharmaceutical Chemistry of jiangxi Province Gannan Normal University

Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

关键词： asymmetric allylation photoredox catalysis radical addition nickel catalysis β-keto esters vinyl cyclopropanes

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Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI wen-bin YUAN Lin zhou jia-sheng LIU Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

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Retinal nerve fiber layer thickness and retinal vascular caliber alterations in coal miners in northern China:a community-based observational study

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International Journal of Ophthalmology(English edition) 2022年第1期15卷 135-140页

作者： Jing-Yan Yang wen-jia zhou Qian Wang Yang Li Yan-Ni Yan Ya-Xing Wang Shou-Ling Wu wen-Bin Wei Beijing Tongren Eye Center Beijing Tongren HospitalBeijing Ophthalmology and Visual Science Key LabBeijing Key Laboratory of Intraocular Tumor Diagnosis and TreatmentCapital Medical UniversityBeijing 100730China Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Key Laboratory of Ophthalmology and Visual SciencesBeijing 100730China Cardiology Department Kailuan General HospitalTangshan 063000Hebei ProvinceChina

AIM:To evaluate retinal nerve fiber layer thickness and retinal vascular caliber alterations in coal mine ***:The community-based observational crosssectional study included 4004 participants of a subpopulation of the Kailuan *** the study participants underwent structured interviews with a standardized questionnaire,fundus photography and spectral-domain optical coherence tomography(OCT)examinations performed by trained ***:The retinal nerve fiber layer thickness was significantly higher(P=0.006)and the central macular thickness was lower in coal miners(n=659,51.0±7.8 y)as compared to the control(working above the ground;n=477,51.8±7.5 y;P=0.032).Additionally,the downhole workers showed a significantly thicker retinal artery(P=0.012)and vein diameters(P<0.001).In multivariable regression,a thicker retinal nerve fiber layer was associated with a higher cumulative silica dust exposure(P=0.005)after adjusting for younger age and larger spherical *** a reverse pattern,a higher cumulative silica dust exposure(P=0.004)was significantly associated with a thicker retinal nerve fiber layer after adjusting for age,high-density lipoproteins and uric *** retinal vein diameters were associated with higher cumulative silica dust exposure(P=0.036)after adjusting for younger age and larger spherical ***:The retinal vessels diameters and retinal nerve fiber layer thickness are significantly thicker in long term of coal *** results of our study indicate that underground working environment may lead to retinal vessel dilation and ***,ocular examination might be needed within coal miners in order to monitor the occupational eye health as well as the incidence and progression of eye diseases.

关键词： retinal vessels diameter retinal nerve fiber layer thickness cumulative silica dust exposure

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Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong Chen Wei-jia Luo Run-Ni Zhao Yong-Zheng wen Ji zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss(Q_(f)).Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Temperature robustness Meta-material absorber Microwave absorption Rare metal-based ceramics Miniaturization

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Myotis bat STING attenuates aging-related inflammation in female mice

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Zoological Research 2024年第5期45卷 961-971页

作者： Xi Wang Jing-Kun jia Qi Wang Jing-wen Gong Ang Li jia Su Peng zhou Wuhan Institute of Virology Chinese Academy of SciencesWuhanHubei 430071China Guangzhou National Laboratory Guangzhou International Bio IslandGuangzhouGuangdong 510005China University of Chinese Academy of Sciences Beijing 100000China State Key Laboratory of Respiratory Disease First Affiliated Hospital of Guangzhou Medical SchoolGuangzhouGuangdong 510005China

Bats,notable as the only flying mammals,serve as natural reservoir hosts for various highly pathogenic viruses in humans(e.g.,SARS-CoV and Ebola virus).Furthermore,bats exhibit an unparalleled longevity among mammals relative to their size,particularly the Myotis bats,which can live up to 40 ***,the mechanisms underlying these distinctive traits remain incompletely *** our prior research,we demonstrated that bats exhibit dampened STING-interferon activation,potentially conferring upon them the capacity to mitigate virus-or aging-induced *** substantiate this hypothesis,we established the first in vivo bat-mouse model for aging studies by integrating Myotis davidii bat STING(MdSTING)into the mouse *** monitored the genotypes of these mice and performed a longitudinal comparative transcriptomic analysis on MdSTING and wild-type mice over a 3-year aging *** transcriptomic analysis indicated a reduction in aging-related inflammation in female MdSTING mice,as evidenced by significantly lower levels of pro-inflammatory cytokines and chemokines,immunopathology,and neutrophil recruitment in aged female MdSTING mice compared to aged wild-type mice in *** results indicated that MdSTING knock-in attenuates the aging-related inflammatory response and may also improve the healthspan in mice in a sex-dependent *** the underlying mechanism awaits further study,this research has critical implications for bat longevity research,potentially contributing to our comprehension of healthy aging in humans.

关键词： Bat STING Longevity Aging-related inflammation Virus reservoir host

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Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia wen Yan Yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable *** also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal *** this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal ***,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity *** by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

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Polyoxometalates-derived nanostructures for electrocatalysis application

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Rare Metals 2024年第5期43卷 1845-1866页

作者： Chao-Yue Sun wen Li Kai Wang Wei-jia zhou Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China Shandong Electrical Engineering and Equipment Group Intelligent Electric Co. Ltd.Jinan 250022China

The conversion of intermittent renewable electrical energy to chemical energy is of great importance which can not only mitigate current energy and environmental crisis but also contribute to the ongoing carbon neutrality national *** is serving as a low-carbon conversion technology that enables green and efficient energy conversion mainly through hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CO_(2)RR),and nitrogen reduction reaction(NRR).The core of electrocatalysis is the design and construction of low-cost high-activity and high-stability electrocatalyst to drive reaction thermodynamics and *** employment of polyoxometalates(POMs)as platforms or precursors to construct different types of electrocatalysts has been widely ***,we systematically summarized the recent advances in POM-derived nanostructures for electrocatalysis *** strategies for precursor design and electrocatalyst synthesis were briefly *** morphology control,phase control,composite modulation,and heterostructure engineering in POM-derived nanostructures were presented in *** structure–activity relationship of POM-derived nanostructures is fully discussed for HER CO_(2)RR,and NRR ***,the current challenges and future outlooks of POM-derived nanostructures are summarized to provide insights toward high-efficiency electrocatalysts for energy conversion technologies.

关键词： Microforming Cylindrical compression Size effects Grain orientation Inhomogeneous deformation

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Deep insight of unique phase transition behaviors and mechanism in Zr_(2)Co-H isotope system with ultra-low equilibrium pressure

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Rare Metals 2024年第1期43卷 212-224页

作者： Yang Liu Pan-Pan zhou Xue-Zhang Xiao jia-Cheng Qi jia-Peng Bi Tiao Ying Xing-wen Feng Yan Shi wen-Hua Luo Li-Xin Chen State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Institute of Materials China Academy of Engineering PhysicsMianyang 621907China Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou 310013China

Efficient capture,safe storage and release of tritium from the international thermonuclear experimental reactor(ITER) reaction exhaust gas is a perplexing problem,and the development of an efficient tritium-getter material with ultra-low hydrogenation equilibrium pressure is considered as a reliable *** this work,Zr_(2)Co alloy was selected as a tritium-getter material and prepared through induction levitation *** performance test results show that Zr_(2)Co exhibits an ultra-low hydrogenation equilibrium pressure of 3.22 × 10^(-6) Pa at 25℃ and excellent hydriding kinetics under a low hydrogen pressure of 0.005 ***,unique phase transition behaviors were presented in Zr_(2)Co-H ***,Zr_(2)CoH_(5) formed by Zr_(2)Co hydrogenated at room temperature is initially decomposed into ZrH_(2) and ZrCoH_(3) at200 ℃.With the temperature increasing to 350 ℃,ZrCoH_(3)is dehydrogenated to ZrCo,and then ZrCo further reacts with ZrH_(2) at 650 ℃ to reform Zr_(2)Co and *** the staged phase transition pathways during dehydrogenation,the decomposition of Zr_(2)CoH_(5) occurs preferentially,which is well accordance with both the smallest reaction energy barrier and the maximum reaction spontaneity that are determined respectively from kinetics activation energy and thermodynamics Gibbs free ***,first principles calculation results indicate that the stronger binding of hydrogen in interstitial environments of ZrCoH_(3)and ZrH_(2) triggers the hydrogen-stabilized phase transformation of Zr_(2)CoH_(5).The unique phase transition mechanisms in Zr_(2)Co-H system can shed light on the further exploration and regulation of analogous staged phase transition of hydrogen storage materials.

关键词： Zr_(2)Co alloy Tritium-getter materials Ultralow equilibrium hydrogen pressure Phase transition mechanism

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