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Doping engineering of iron oxide nanoparticles towards high performance and biocompatible T_(1)-weighted MRI contrast agents

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Rare Metals 2024年第1期43卷 298-308页

作者： Xue Xu Ping-Li Dong Yu-Yun chai Run Yang zhen-Hui Ma Chi-Chong Lu Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China Department of Physics Beijing Technology and Business UniversityBeijing 100048China

Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast *** when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor *** doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed ***,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and ***,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal ***,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding ***_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)*** stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.

关键词： Iron oxide nanoparticles Small size Magnetic resonance imaging Substitutional doping Gd dopant

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Theoretical and experimental investigations on an X-shaped vibration isolator with active controlled variable stiffness

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1371-1386页

作者： Zeyu chai J.T.HAN Xuyuan SONG Jian ZANG Yewei ZHANG zhen ZHANG College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Jacobs School of Engineering University of California San DiegoSan Diego CA 92122U.S.A. Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of EducationNortheastern UniversityShenyang 110819China

A novel X-shaped variable stiffness vibration isolator(X-VSVI)is *** Runge-Kutta method,harmonic balance method,and wavelet transform spectra are introduced to evaluate the performance of the X-VSVI under various *** layer number,the installation angle of the X-shaped structure,the stiffness,and the active control parameters are systematically *** addition,a prototype of the X-VSVI is manufactured,and vibration tests are carried *** results show that the proposed X-VSVI has a superior adaptability to that of a traditional X-shaped mechanism,and shows excellent vibration isolation performance in response to different amplitudes and forms of ***,the vibration isolation efficiency of the device can be improved by appropriate adjustment of parameters.

关键词： bionic vibration isolation X-shaped structure variable stiffness structure nonlinear dynamics prototype experiment

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Efficacy and safety of Nafamostat mesylate in patients with endstage renal failure

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World Journal of Clinical Cases 2024年第1期12卷 68-75页

作者： Kun Liu zhen-hua Li Department of Critical Care Medicine The Third People's Hospital Of Hubei ProvinceWuhan 430030Hubei ProvinceChina Department of Critical Care Medicine General Hospital of The Yangtze River ShippingWuhan Brain HospitalWuhan 430015Hubei ProvinceChina

BACKGROUND Recent studies on dialysis anticoagulation therapy in patients with renal failure have shown that Nafamostat mesylate,a broad-spectrum potent serine protease inhibitor,has strong anticoagulation and anti-fiber *** To evaluate the efficacy and safety of Nafamostat mesylate in patients with end-stage renal *** Seventy-five patients with end-stage renal failure who received hemodialysis at our hospital between January 2020 and August 2021 were selected and divided into the observation group(Nafamostat mesylate for injection,n=33)and control group(heparin sodium injection,n=32).General patient data,indicators of clinical efficacy,dialyzer hemocoagulation parameters,coagulation function indices,and hemoglobin concentration and platelet count before and after treatment,and the occurrence of adverse reactions after treatment were compared between the two *** The two groups showed no significant differences in general patient data(P>0.05).The post-treatment effectiveness rate in the control group was lower than that in the observation group(P0.05),while the number of patients in grade 0 was lower in the control group,and the number of patients in grades II and III was higher in the control group(P0.05).The total number of post-treatment adverse reactions in the observation group was lower than that in the control group(P<0.05).CONCLUSION Treatment of patients showing end-stage renal failure with Nafamostat mesylate can s

关键词： End-stage renal failure Nafamostat mesylate Effectiveness Safety study Chronic kidney diseases

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Enhanced wide-angle third-harmonic generation in flat-band-engineered quasi-BIC metagratings

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 81-87页

作者： Yijia Zang Ruoheng chai Wenwei Liu Zhancheng Li hua Cheng Jianguo Tian Shuqi Chen The Key Laboratory of Weak Light Nonlinear Photonics Ministry of EducationSchool of Physics and TEDA Institute of Applied PhysicsNankai UniversityTianjin 300071China School of Materials Science and Engineering Smart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350China The Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Nonlinear metasurfaces and photonic crystals provide a significant way to generate and manipulate nonlinear signals owing to the resonance-and symmetry-based light-matter interactions supported by the artificial ***,the nonlinear conversion efficiency is generally limited by the angular dispersion of optical resonances especially in nonparaxial ***,we propose a metagrating realizing a quasi-bound-state in the continuum in a flat band to dramatically improve the third harmonic generation(THG)efficiency.A superior operating angular range is achieved based on the interlayer and intralayer couplings,which are introduced by breaking the mirror symmetry of the *** demonstrate the relation of angular dispersion between the nonlinear and linear responses at different incident *** also elucidate the mechanism of these offaxis flat-band-based nonlinear conversions through different mode *** scheme provides a robust and analytical way for nonparaxial nonlinear generation and paves the way for further applications such as wide-angle nonlinear information transmission and enhanced nonlinear generation under tight focusing.

关键词： nonlinear metasurfaces quasi-bound-state in the continuum angular dispersion third harmonic generation efficiency

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Resurgence of pertussis:reasons and coping strategies

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World Journal of Pediatrics 2024年第7期20卷 639-642页

作者： Chun-zhen hua Han-Qing He Qiang Shu Department of Infectious Diseases National Clinical Research Center for Child HealthChildren’s HospitalZhejiang University School of MedicineHangzhou310052China Department of Immunization Program Zhejiang Provincial Center for Disease Control and PreventionHangzhou310051China National Clinical Research Center for Child Health Children’s HospitalZhejiang University School of MedicineHangzhou310052China

Pertussis(whooping cough)is an acute and contagious respiratory disease caused by the pathogen Bordetella pertussis(***).*** can infect individuals of all *** with pertussis may experience severe and persistent coughing and paroxysms;for newborns and infants,pertussis may be *** development and widespread administration of the pertussis vaccine had once successfully brought pertussis under control,maintaining it at a low level for many ***,resurgence of pertussis has been reported in many countries even with high vaccination coverage *** resurgence of pertussis was first reported in the United States(USA)in 1993[1].During 2000–2016,the baseline incidence increased and the age distribution of pertussis changed in the USA[2].Other countries including Canada[3],Australia[4],European Union countries,and South Korea have also reported a rise in pertussis outbreaks[2,5].

关键词： pertussis Canada surge

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Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality

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Petroleum Science 2024年第3期21卷 2139-2153页

作者： zhen-hua Zhang Dan Ling Qin-Xin Yang Yan-Chao Feng Jing Xiu School of Economics Lanzhou UniversityLanzhou 730000GansuChina Institute of Green Finance Lanzhou UniversityLanzhou 730000GansuChina School of Management Lanzhou UniversityLanzhou 730000GansuChina School of Business Zhengzhou UniversityZhengzhou 450001HenanChina Institute of Economics Jilin Academy of Social SciencesChangchun130033JilinChina

Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction *** study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each *** research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI *** the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary ***,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy *** study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy.

关键词： Central environmental protection inspection Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction

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Recent progress of Pt-based oxygen reduction reaction catalysts for proton exchange membrane fuel cells

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Rare Metals 2024年第6期43卷 2444-2468页

作者： Feng Zhan Kun-Song Hu Jin-hua Mai Li-Sheng Zhang zhen-Guo Zhang huan He Xin-hua Liu School of Resources Environment and MaterialsGuangxi UniversityNanning530004China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China IDTECH(Suzhou)Co.Ltd Suzhou 215217China Dyson School of Design Engineering Imperial College LondonLondon SW72AZUK

With the increasing consumption of fossil fuels,proton exchange membrane fuel cells(PEMFCs)have attracted considerable attention as green and sustainable energy conversion *** slow kinetics of the cathodic oxygen reduction reaction(ORR)has a major impact on the performance of PEMFCs,and although platinum(Pt)can accelerate the reaction rate of the ORR,the scarcity and high cost of Pt resources still limit the development of ***,the development of low-cost high-performance ORR catalysts is essential for the commercial application and development of *** paper reviews the research progress of researchers on Pt-based ORR catalysts in recent years,including Pt/C catalysts,Pt-based alloy catalysts,Pt-based intermetallic compounds,and Pt-based single-atom catalysts(SACs),with a focus on Pt-based alloy catalysts with different *** described in detail the difficulties and solutions in the research process of various ORR catalysts and explained the principle of their activity enhancement with density functional theory(DFT).In addition,an outlook on the development of Pt-based catalysts is given,and reducing the amount of Pt used and improving the performance of catalysts are the directions to work on in the coming period.

关键词： Pt-based catalysts PEMFCs Pt-based intermetallic compounds Single-atom catalysts

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Microstructural Evolutions and Mechanical Properties of Energetic Al_(1) (TiZrNbTaMoCr)_(15) High-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 620-632页

作者： Xuan-Hong Cai zhen-hua Wang Ben Niu Jin-Feng Li Qing Wang Show authors Key Laboratory of Materials Modification By Laser Ion and Electron Beams(Ministry of Education)Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

The present study focuses on investigating the microstructural evolutions and mechanical properties of energetic Al_(1)(TiZrNbTaMoCr)_(15) refractory high-entropy alloys with the different heat treatments at low Al content state. It is found that even with a reduction in the Al content, the strength of these alloys remains unaffected at room temperature and high temperature, while the plasticity improves significantly. In particular, the coherent BCC/B_(2) microstructure with needle-like B_(2) nanoprecipitates dispersed into the BCC matrix is formed in 873 K-aged Al_(1)Ti_(6)Zr_(2)Nb_(3)Ta_(3)Mo_(0.5)Cr_(0.5) alloy. Therefore, this alloy exhibits the highest compression yield strength (σ_(YS) = 1333 and 717 MPa) at room temperature and 1073 K, respectively. After 973 K-aged, the coherent BCC/B_(2) microstructure underwent destabilization, and the B_(2) phase transforms into the brittle Zr5Al3 phase which then coarsens and dominates the microstructure of S3-AlTa_(3) alloy after 1073 K-aged. Moreover, these current alloys exhibit exceptionally high theoretical exothermic enthalpy (ΔH), surpassing 11606 J·g^(−1), which highlights their significant potential as innovative high-performance energetic structural materials.

关键词： Refractory high-entropy alloy Coherent microstructure Mechanical property Exothermic enthalpy

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Laser manufacturing of spatial resolution approaching quantum limit

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Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang Hong-hua Fang zhen-Ze Li Dan Wang Hong-Bo Sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size of<5 nm is *** underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident *** show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to *** a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

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Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand

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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： Pei-Yu Liao Yu-Quan Qi zhen Li Jian-hua Jia Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

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