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Rare Metals 2024年第10期43卷 5403-5409页

作者： Jian-Qiu Sun Yue Ma Chong Gao hong-Yun Luo School of Materials Science and Engineering Beihang University Chinalco Research Institute of Science and technology

In order to improve the comprehensive mechanical properties,deep cryogenic treatment （DCt）prior to aging was carried out on friction-stir-welded（FSW） 2198 Al-Li alloy;afterward,the microstructure and tensile properties were characterized by means of optical microscopy （OM）,t.ansmission electron microscopy（tEM） and tensile *** results show that FSW 2198 alloy through DCt prior to aging （DAt） possesses superior tensile properties t.an conventional aging treatment （At）the microstructural analysis reveals that DAt alloy exhibits a finer grain structure,since DCt might effectively alleviate the residual stress in FSW 2198 alloy and thus decrease the driving force for grain coarsening in subsequent aging ***,DCt generates dislocation multiplication,which provides more preferential nucleation sites for t1 （Al2CuLi） phase during subsequent aging treatment,resulting in high-density fine t1 phases and thin precipitate-free zone within DAt *** reasonable microstructure leads to DAt alloy possessing better strength-ductility combination compared to At alloy.

关键词： Al–Li alloy Deep cryogenic treatment Friction stir welding tensile properties

A study of the effect of local scour on the flow field near the spur dike

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theoretical & Applied Mechanics Letters 2024年第2期14卷 98-105页

作者： Yu-t.an Li Jie-Min Zhan Wing-hong Onyx Wai Department of Industrial Design School of Industrial Design and Ceramic ArtFoshan UniversityFoshan 528000China Department of Applied Mechanics and Engineering Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

the flow field near a spur dike such as down flow and horseshoe vortex system(HVS)are susceptible to the topographic changes in the local scouring process,resulting in variation of the sediment t.ansport with *** this study,large eddy simulations with fixed-bed at different scouring stages were conducted to investigate the changes in flow *** results imply that the bed deformation leads to an increase in flow rate per unit area,which represent the capability of sediment t.ansportation by water,in the scour ***,the intensity of turbulent kinetic energy and bimodal motion near the sand bed induced by the HVS were also ***,the peak moments between the two sediment t.ansport mechanisms were ***,understanding the complex feedback mechanism between topography and flow field is essential for the local scour problem.

关键词： Spur dike Local scour Large eddy simulation Down flow Horseshoe vortex system

Bond behavior of the interface between concrete and basalt fiber reinforced polymer bar after freeze–thaw cycles

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 630-641页

作者： Li hong Mingming LI Congming DU Shenjiang HUANG Binggen ZHAN Qijun YU Department of Structural Engineering Hefei University of TechnologyHefei 230009China Key Laboratory of Performance Evolution and Control for Engineering Structures Tongji UniversityShanghai 200092China Engineering Research Center of Low-carbon technology and Equipment for Cement-based Materials(Ministry of Education) Hefei University of TechnologyHefei 230009China Hefei Cement Research&Design Institute Corporation Ltd. Hefei 230051China

the shear bond of interface between concrete and basalt fiber reinforced polymer(BFRP)bars during freeze–thaw(F–t)cycles is crucial for the application of BFRP bar-reinforced concrete structures in cold *** this study,48 groups of pull-out specimens were designed to test the shear bond of the BFRP-concrete interface subjected to F–t *** effects of concrete strength,diameter,and embedment length of BFRP rebar were investigated under numerous F–t *** results showed that a larger diameter or longer embedment length of BFRP rebar resulted in lower interfacial shear bond behavior,such as interfacial bond strength,initial stiffness,and energy absorption,after the interface goes through F–t ***,higher concrete strength and fewer F–t cycles were beneficial for enhancing the interfacial bond ***,a three-dimensional(3D)interfacial model based on the finite element method was developed,and the interfacial bond behavior of the specimens was analyzed ***,a degradation bond strength subjected to F–t cycles was predicted by a proposed mechanical *** predictions were fully consistent with the tested *** model demonstrated accuracy in describing the shear bond behavior of the interface under numerous F–t cycles.

关键词： F-t cycle interface shear bond strength bond stress−slip curves bond degradation

Singularity analysis and avoidance for an SSRMS-type reconfigurable space manipulator with a non-spherical wrist.and two lockable passive telescopic links

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Chinese Journal of Aeronautics 2024年第8期37卷 435-459页

作者： Zhiyuan ZHAO Xiaohang YANG Yuntao LI Zichun XU Jingdong ZHAO hong LIU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

this study focuses on addressing kinematic singularity analysis and avoidance issues for a space station remote manipulator system(SSRMS)-type reconfigurable space *** manipulator is equipped with a non-spherical wrist.and two lockable passive telescopic links(LPtLs),which enable it to have both active revolute and passive prismatic joints and operate in two distinct *** begin with the kinematic singularity analysis,the study derives the differential kinematic equations for the manipulator and identifies the dominant Jacobian matrix that causes ***,an in-depth analysis of singularities from multiple perspectives is ***,a kinematic singularity map method is proposed to capture the distribution of singularities within the reachable ***,the influence of the two LPtLs on singularities is thoroughly ***,a new method based on the matrix rank equivalence principle is introduced to determine singularity conditions,enabling the identification of all the singular configurations for the SSRMS-type reconfigurable ***,this method significantly reduces computational complexity,and the singularity conditions obtained have more concise *** the singularity avoidance problem,a novel method is developed,which simultaneously addresses the requirements of real-time performance,high precision,and the avoidance of both kinematic singularities and joint limit *** from these excellent properties,the proposed method can effectively resolve the singularity issues encountered separately by the SSRMS-type reconfigurable manipulator in its two operational *** typical simulations validate the utility of all the proposed methods.

关键词： Reconfigurable space manipulator Redundant manipulator Kinematics Singularity analysis Singularity avoidance

Insights into the changes in the surface properties of goethite with Ni in the lattice in the presence of salicylhydroxamic acid:Experimental and density functional theory studies

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 665-677页

作者： Levie Mweene Gilsang hong Hee-Eun Jeong Hee-won Kang Hyunjung Kim Department of Earth Resources and Environmental Engineering Hanyang University222 Wangsimni-roSeongdong-guSeoul 04763Republic of Korea

Comparative experiments and theoretical analysis of the surface chemistry changes of goethite(Gt.and goethite containing Ni(GtN)in the lattice in the presence of salicylhydroxamic acid(SA)were *** was revealed that in the presence of 100 g·t^(-1)of SA,the flotation recovery of GtN and Gt increased with increasing pH,achieving a maximum recovery of 98.9%for both minerals at p H 8.3 and decreasing beyond that pH,with GtN having a slightly higher recovery t.an Gt,except at pH *** was further confirmed by the higher complexation energies of GtN···SA(-883.87 kJ·mol^(-1))compared with Gt···SA(-604.23 kJ·mol^(-1))resulting from covalent,closed-shell,and conventional hydrogen *** higher adsorption of SA onto GtN relative to Gt was due to the formation of aπ-hole in GtN,thereby promoting a higher interaction of the collector with the ***,the presence of Ni in the Gt lattice improves and decreases the adsorption and desorption of SA onto and from the mineral,respectively,compared with those onto and from Gt.

关键词： nickel goethite adsorption salicylhydroxamic acid recovery

Multiplicity of solutions for the semilinear subelliptic Dirichlet problem

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Science China Mathematics 2024年第3期67卷 475-504页

作者： Hua Chen hong-Ge Chen Jin-Ning Li Xin Liao School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In this paper,we study the semilinear subelliptic equation{−△Xu=f(x,u)+g(x,u)inΩ,u=0 on∂Ω,where△X=−∑m i=1 Xi∗Xi is the self-adjoint Hormander operator associated with the vector fields X=(X_(1),X_(2),...,X_(m))satisfying the Hormander's condition,f(x,u)∈C(Ω×R),g(x,u)is a Carathéodory function onΩ×R,andΩis an open bounded domain in R~n with smooth *** the perturbation from the symmetry method with the approaches involving the eigenvalue estimate and the Morse index in estimating the minimax values,we obtain two kinds of existence results for multiple weak solutions to the problem ***,we discuss the difference between the eigenvalue estimate approach and the Morse index approach in degenerate *** with the classical elliptic cases,both approaches here have their own strengths in the degenerate *** new phenomenon implies that the results in general degenerate cases would be quite different from the situations in classical elliptic cases.

关键词： degenerate elliptic equations Hormander operators perturbation method Morse index

the Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 630-640页

作者： XIE Qifeng DONG Yunpeng CAI Yuanfeng ZHAI Mingguo XIAO Aifang ZHANG hong Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

the magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still *** results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.the Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock *** samples are enriched in HFSEs(i.e.,ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of *** the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/ta etc.,they were proved to be alkaline A-type *** the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization *** values of ε_(Hf)(t.and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement *** comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

关键词： A-type granitoid geochronology extension subduction Mesozoic Southeast China

Comparison of fungal vs bacterial infections in the medical intensive liver unit:Cause or corollary for high mortality?

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World Journal of Hepatology 2024年第3期16卷 379-392页

作者： Sarah Khan Hanna hong Stephanie Bass Yifan Wang Xiao-Feng Wang Omar t Sims Christine E Koval Aanchal Kapoor Christina C Lindenmeyer Department of Internal Medicine Cleveland ClinicClevelandOH 44195United States Cleveland Clinic Lerner College of Medicine Cleveland ClinicClevelandOH 44195United States Department of Pharmacy Cleveland ClinicClevelandOH 44195United States Department of Quantitative Health Sciences/Biostatistics Section Cleveland ClinicClevelandOH 44195United States Department of Gastroenterology Hepatology and NutritionCleveland ClinicClevelandOH 44195United States Department of Infectious Disease Cleveland ClinicClevelandOH 44195United States Department of Critical Care Medicine Cleveland ClinicClevelandOH 44195United States

BACKGROUND Due to development of an immune-dysregulated phenotype,advanced liver disease in all forms predisposes patients to sepsis acquisition,including by opportunistic pathogens such as *** data exists on fungal infection within a medical intensive liver unit(MILU),particularly in relation to acute on chronic liver *** to investigate the impact of fungal infections among critically ill patients with advanced liver disease,and compare outcomes to those of patients with bacterial *** From our prospective registry of MILU patients from 2018-2022,we included 27 patients with culture-positive fungal infections and 183 with bacterial *** compared outcomes between patients admitted to the MILU with fungal infections to bacterial *** was extracted through chart *** All fungal infections were due to Candida species,and were most frequently blood *** among patients with fungal infections was significantly worse relative to the bacterial cohort(93%vs 52%,Pthe majority of the fungal cohort developed grade 2 or 3 acute on chronic liver failure(ACLF)(90%vs 64%,P=0.02).Patients in the fungal cohort had increased use of vasopressors(96%vs 70%,P=0.04),mechanical ventilation(96%vs 65%,Pto acute kidney injury(78%vs 52%,P=0.014).On MILU admission,the fungal cohort had significantly higher Acute Physiology and Chronic Health Evaluation(108 vs 91,P=0.003),Acute Physiology Score(86 vs 65,P=0.003),and Model for End-Stage Liver Disease-Sodium scores(86 vs 65,P=0.041).there was no significant difference in the rate of central line use preceding culture(52%vs 40%,P=0.2).Patients with fungal infection had higher rate of t.ansplant hold placement.and lower rates of t.ansplant;however,differences did not achieve statistical *** Mortality was worse among patients with fungal infections,likely attributable to severe ACLF *** studies examinin

关键词： Fungal Infection Sepsis Acute on chronic liver failure Intensive care

An organic free radical generator independent on hydrogen peroxide for chemodynamic and immunotherapy in vivo

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Journal of Materials Science & technology 2024年第7期174卷 85-94页

作者： Yang Chen Yunpeng Song Chaojie tang hong Yang Wu Wang Shiping Yang Zhiguo Zhou College of Chemistry and Materials Science International Joint Laboratory on Resource Chemistry of Ministry EducationShanghai Frontiers Science Center of Biomimetic CatalysisShanghai Normal UniversityShanghai 200234China Institute of Diagnostic and Interventional Radiology Shanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghai 200233China

It is desirable to develop a free radical generator that is neither dependent on hydrogen peroxide nor external stimuli-triggered to achieve effective tumor ***,the free radical genera-tor MNPs-mCPBA was constructed with Zn_(0.4)Co_(0.6)F_(e2)O_(4)@Zn_(0.4)Mn_(0.6)Fe_(2)O_(4)nanoparticles(MNPs)and 3-chloroperbenzoic acid(mCPBA).We believe that the iron(Ⅱ)on the surface of MNPs-mCPBA maybe represent high reactive activity and promote the generation of a large number of organic free radicals(C_(6)H_(4)ClCOOO)in an acidic tumor microenvironment,which realizes the acid-dependent tumor treat-ment strategy independent on the H_(2)O_(2)level in *** addition,the generated organic free radicals(C_(6)H_(4)ClCOOO)effectively induced immunogenic cell death(ICD)and increased t cell ***-der the synergetic treatment with an anti-PD-L1 antibody(α-PD-L1),a favorable anti-tumor effect was achieved.

关键词： Organic free radicals Immunogenic cell death Immunotherapy Chemodynamic therapy

thoracic spinal cord injury and paraplegia caused by intradural cement leakage after percutaneous kyphoplasty: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1837-1843页

作者： Zi Mao Zhi-hong Xiong Jun-Feng Li Department of Pain Management The Affiliated Hospital of Yunnan UniversityKunming 650000Yunnan ProvinceChina Department of Medical Administration The Affiliated Hospital of Yunnan UniversityKunming 650000Yunnan ProvinceChina

BACKGROUND Percutaneous kyphoplasty(PKP)is a pivotal intervention for osteoporotic fractures,pathological vertebral compression fractures,and vertebral bone *** its efficacy,the procedure presents challenges,notably complications arising from intradural cement *** and accurate diagnosis,coupled with emergent intervention is imperative to improve patient *** case report illuminates the intricacies and potential complications associated with PKP,emphasizing the critical need for vigilant monitoring,prompt diagnosis,and immediate intervention to mitigate adverse *** SUMMARY A 58-year-old male patient,experiencing a t7 osteoporosis-related pathological compression fracture,underwent PKP at a local *** weeks postprocedure,the patient developed paraplegic and dysuric symptoms,necessitating emergency decompression *** improvement was achieved,marked by the restoration of muscle strength,sensation,and *** PKP Intradural cement leakage following PKP is unusual and potentially *** imaging examinations,urgent evaluation,and the decompression surgery are essential,which help alleviate symptoms associated with spinal damage,markedly improving the overall prognosis.

关键词： Percutaneous kyphoplasty Intradural cement leakage Complication Decompression surgery Case report