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Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang Wen-Qing Wang jia-Ping Lin Li-quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

Nitric oxide assists nitrogen reduction reaction on 2D MBene: A theoretical study

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Chinese Chemical Letters 2024年第5期35卷 428-433页

作者： Chaozheng He jia Wang Ling fu Wei Wei Henan Engineering Center of New Energy Battery Materials College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu 476000China School of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory/Collaborative Innovation Center of Chemical Energy Storage&Novel Cell TechnologyLiaocheng UniversityLiaocheng 252059China Institute of Environment and Energy Catalysis Shaanxi Key Laboratory of Optoelectronic Functional Materials and DevicesSchool of Materials Science and Chemical EngineeringXi’an Technological UniversityXi’an 710021China College of Resources and Environmental Engineering Tianshui Normal UniversityTianshui 741001China

Electrocatalytic synthesis of ammonia as an environment-friendly and sustainable development method has received widespread attention in recent years.Two-dimensional(2D)materials are a promising catalyst for ammonia synthesis due to their large surface area.In this work,we have constructed a series of 2D metal borides(MBenes)with transition metal(TM)defects(TMd-MBenes)and comprehensively calculated the reactivity of electrocatalytic synthesis of ammonia-based on density functional theory.The results have demonstrated that the TMd-MBenes can effectively activate nitrogen oxide(NO)and nitrogen(N2)molecules thermodynamically.Particularly interesting,the co-chemisorption of O atoms,dissociated from NO,can facilitate the spilled of the inert N2 molecules into single N atoms,which can further hydrogenate into ammonia easily with an ultralow limiting potential of 0.59 V on TMd-MnB.Our research has not only provided clues for catalyst design for experimental study but also paved the way for the industrial application of electrocatalytic ammonia synthesis.

关键词： 2D mbenes Nitrogen electro-reduction DFT N_(2)activation Ammonia synthesis

Effects of two silicone resin coatings on performance of FeSiAl magnetic powder cores

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1279-1288页

作者： jia-qi Liu Zheng-qu Zhu Pu Wang Yi-fan Li Jing Pang jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao266232ShandongChina

Two silicon resins with excellent thermal stability,JH1123 and JH7102,are used as the insulated agents and binders for the gas-atomized FeSiAl powder,and corresponding magnetic powder cores(MPCs)are fabricated.The insulation capability and application prospects of the two silicon resins are evaluated by comparing the magnetic properties of the coated powder and MPCs.The scanning electron microscopy,energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy results show that uniform insulation layers are both formed on the powder surfaces.JH1123 has stronger binding ability,and the JH1123-coated powder exhibits severe agglomeration,with d50(average particle size)approximately twice that of the JH7102-coated powder.Both as-prepared MPCs exhibit outstanding soft magnetic properties.Wherein,the permeability of FeSiAl@JH1123 is up to 74.0,which is 35.5%higher than that of FeSiAl@JH7102 because JH1123 can further improve the density of the MPCs.As for FeSiAl@JH7102,it has better direct current bias and lower core loss of 716.9 mW cm^(−3) at 20 mT and 1000 kHz due to its lower coercivity and greater anti-magnetic saturation ability.A comprehensive comparison shows that FeSiAl@JH1123 is suitable for medium and high frequency applications,while FeSiAl@JH7102 is more suitable for high frequency applications.This indicates that the use of JH1123 and JH7102 silicon resins for binding and insulated coating not only simplifies the preparation process of MPCs,but also enables the controlled production of MPCs for different applications.

关键词： FeSiAl Insulated coating Magnetic powder core Permeability Core loss

Structural insights into the Oryza sativa cation transporters HKTs in salt tolerance

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Journal of Integrative Plant Biology 2024年第4期66卷 700-708页

作者： Ran Gao Yutian jia Xia Xu Peng fu jiaqi Zhou Guanghui Yang State Key Laboratory of Plant Environmental Resilience Frontiers Science Center for Molecular Design BreedingCollege of Biological SciencesChina Agricultural UniversityBeijing 100193China

The high-affinity potassium transporters(HKTs),selectively permeable to either Na^(+)alone or Na^(+)/K^(+),play pivotal roles in maintaining plant Na^(+)/K^(+)homeostasis.Although their involvement in salt tolerance is widely reported,the molecular underpinnings of Oryza sativa HKTs remain elusive.In this study,we elucidate the structures of OsHKT1;1 and OsHKT2;1,representing two distinct classes of rice HKTs.The dimeric assembled OsHKTs can be structurally divided into four domains.At the dimer interface,a half-helix or a loop in the third domain is coordinated by the C-terminal region of the opposite subunit.Additionally,we present the structures of OsHKT1;5 salt-tolerant and salt-sensitive variants,a key quantitative trait locus associated with salt tolerance.The salt-tolerant variant of OsHKT1;5 exhibits enhanced Na^(+)transport capability and displays a more flexible conformation.These findings shed light on the molecular basis of rice HKTs and provide insights into their role in salt tolerance.

关键词： HKT salt-tolerant structure

Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation

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Research in Astronomy and Astrophysics 2024年第1期24卷 173-177页

作者： fu-Lin Dai quan-Bu Gou Xiaoyuan Huang Yi-Qing Guo Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is proposed as the early stage of the GRAND project,consisting of a hybrid array of radio antennas and scintillator detectors.The latter,as a mature and traditional detector,is used to cross-check the nature of the candidate events selected from radio observations.In this study,we developed a simulation software called G4GRANDProto300,based on the Geant4 software package,to optimize the spacing of the scintillator detector array and to investigate its effective area.The analysis was conducted at various zenith angles under different detector spacings,including 300,500,600,700,and 900 m.Our results indicate that,for large zenith angles used to search for cosmic-ray in the GRAND project,the optimized effective area is with a detector spacing of 500 m.The G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work.

关键词： astroparticle physics instrumentation:detectors (ISM:)cosmic rays

Chemical Composition, Pharmacological Effects and Clinical Applications of Cinobufacini

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Chinese Journal of Integrative Medicine 2024年第4期30卷 366-378页

作者： ZUO Qian XU Ding-qiao YUE Shi-jun fu Rui-jia TANG Yu-ping Key Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi University of Chinese MedicineXi'an(712046)China

Chinese medicine cinobufacini is an extract from the dried skin of Bufo bufo gargarizans Cantor,with active ingredients of bufadienolides and indole alkaloids.With further research and clinical applications,it is found that cinobufacini alone or in combination with other therapeutic methods can play an anti-tumor role by controlling proliferation of tumor cells,promoting apoptosis,inhibiting formation of tumor neovascularization,reversing multidrug resistance,and regulating immune response;it also has the functions of relieving cancer pain and regulating immune function.In this paper,the chemical composition,pharmacological effects,clinical applications,and adverse reactions of cinobufacini are summarized.However,the extraction of monomer components of cinobufacini,the relationship between different mechanisms,and the causes of adverse reactions need to be further studied.Also,high-quality clinical studies should be conducted.

关键词： cinobufacini chemical composition Chinese medicine pharmacological effect clinical application adverse effect

Application and progress of artificial intelligence technology in the segmentation of hyperreflective foci in OCT images for ophthalmic disease research

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1138-1143页

作者： jia-Ning Ying Hu Li Yan-Yan Zhang Wen-Die Li quan-Yong Yi Ningbo Eye Hospital Wenzhou Medical UniversityNingbo 315042Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina

With the advancement of retinal imaging,hyperreflective foci(HRF)on optical coherence tomography(OCT)images have gained significant attention as potential biological biomarkers for retinal neuroinflammation.However,these biomarkers,represented by HRF,present pose challenges in terms of localization,quantification,and require substantial time and resources.In recent years,the progress and utilization of artificial intelligence(AI)have provided powerful tools for the analysis of biological markers.AI technology enables use machine learning(ML),deep learning(DL)and other technologies to precise characterization of changes in biological biomarkers during disease progression and facilitates quantitative assessments.Based on ophthalmic images,AI has significant implications for early screening,diagnostic grading,treatment efficacy evaluation,treatment recommendations,and prognosis development in common ophthalmic diseases.Moreover,it will help reduce the reliance of the healthcare system on human labor,which has the potential to simplify and expedite clinical trials,enhance the reliability and professionalism of disease management,and improve the prediction of adverse events.This article offers a comprehensive review of the application of AI in combination with HRF on OCT images in ophthalmic diseases including age-related macular degeneration(AMD),diabetic macular edema(DME),retinal vein occlusion(RVO)and other retinal diseases and presents prospects for their utilization.

关键词： artificial intelligence deep learning hyperreflective foci image analysis

Insight into the Role of Isolated Gold Atoms-Ceria Conjunction in Catalyzing the Water-Gas Shift Reaction

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Chinese Journal of Chemistry 2024年第6期42卷 636-644页

作者： Xin-Pu fu Hui-Zhao Wei-Wei Wang Chun-jiang jia Key Laboratory for Colloid and Interface Chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong250100 China

As the promising catalysts for the water-gas shift(WGS)reaction,the activity of Au-CeO_(2) composites is susceptible to the aggregation size and electronic state of Au species.Previous reports were extensively focused on the discrepancy between nonmetallic Au and metallic Au nanoparticles,whereas the understanding of the authentic role of the isolated Au atoms was limited.Herein,we investigated the catalytic behavior and structural information over two types of Au/CeO_(2) catalysts,in which the predominant conjunctions were isolated Au1-CeO_(2) and Aun-CeO_(2),respectively.Based on comprehensive characterizations,particularly by in-situ Raman and in-situ DRIFTS,we found that the isolated Au atoms were responsible for enhancing the reducibility of the CeO_(2) matrix.The CO adsorption ability on the isolated Au sites was significantly inferior to clustered Au atoms,especially at relatively high temperatures(>200°C).As a result,the boosted O vacancy on the isolated Au1-CeO_(2) conjunctions could improve the H2O activation ability for the Au-CeO_(2) catalysts and demonstrate a comparable activity to the clustered Aun-CeO_(2) sites.This work might deepen understanding of the catalytic function for the isolated Au1 site within Au/CeO_(2) systems while catalyzing the WGS reaction.

关键词： Isolated Au atoms Ceria-based catalysts Water-gas shift reaction Defect Adsorption

Casual associations between blood metabolites and colon cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1995-2005页

作者： Ke-Yue Hu Yi-quan Cheng Zhi-Long Shi fu-Peng Ren Gang-Feng Xiao Department of Hematology and Oncology Ningbo No.2 HospitalNingbo 315000Zhejiang ProvinceChina

BACKGROUND Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal cancer.AIM To investigate causal associations between blood metabolites and colon cancer.METHODS The study utilized a two-sample Mendelian randomization(MR)analysis to investigate the causal impact of 486 blood metabolites on colorectal cancer.The primary method of analysis used was the inverse variance weighted model.To further validate the results several sensitivity analyses were performed,including Cochran's Q test,MR-Egger intercept test,and MR robust adjusted profile score.These additional analyses were conducted to ensure the reliability and robustness of the findings.RESULTS After rigorous selection for genetic variation,486 blood metabolites were included in the MR analysis.We found Mannose[odds ratio(OR)=2.09(1.10-3.97),P=0.024],N-acetylglycine[OR=3.14(1.78-5.53),P=7.54×10^(-8)],X-11593-O-methylascorbate[OR=1.68(1.04-2.72),P=0.034],1-arachidonoylglycerophosphocholine[OR=4.23(2.51-7.12),P=6.35×10^(-8)]and 1-arachidonoylglycerophosphoethanolamine 4[OR=3.99(1.17-13.54),P=0.027]were positively causally associated with colorectal cancer,and we also found a negative causal relationship between Tyrosine[OR=0.08(0.01-0.63),P=0.014],Urate[OR=0.25(0.10-0.62),P=0.003],N-acetylglycine[0.73(0.54-0.98),P=0.033],X-12092[OR=0.89(0.81-0.99),P=0.028],Succinylcarnitine[OR=0.48(0.27-0.84),P=0.09]with colorectal cancer.A series of sensitivity analyses were performed to confirm the rigidity of the results.CONCLUSION This study showed a causal relationship between 10 blood metabolites and colorectal cancer,of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk factors.The other five blood metabolites are protective factors.

关键词： Metabolites Colon cancer Mendelian randomization Genome-wide association studies Casual