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Numerical design of an efficient Ho^(3+)-doped InF3 fiber laser at~3.2μm

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journal of Electronic Science and Technology 2024年第3期22卷 35-46页

作者： Shi-Yuan zhou Hong-Yu Luo ya-zhou Wang Yong Liu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China DTU Electro Technical University of DenmarkKongens Lyngby2800Denmark

In this work,we theoretically unlock the potential of Ho^(3+)-doped InF3 fiber for efficient~3.2μm laser generation(from the 5F4,5S2→5F5 transition),by employing a novel dual-wavelength pumping scheme at 1150 nm and 980 nm,for the first *** clad-coupled 1150 nm pumping of 5 W,~3.2μm power of 3.6 W has been predicted with the optical-to-optical efficiency of 14.4%.Further efficient power scaling,however,is blocked by the output saturation with 980 nm *** alleviate this behavior,the cascaded 5I5→5I6 transition,targeting~3.9μm,has been activated simultaneously,therefore accelerating the population circulation between the laser upper level 5F4,5S2 and long-lived 5I6 level under 980 nm *** a result,enhanced~3.2μm power of 4.68 W has been obtained with optical-to-optical efficiency of 15.6%.Meanwhile the~3.9μm laser,yielding power of 2.76 W with optical-to-optical efficiency of 9.2%,is theoretically achievable as well with a moderate heat load,of which the performance is even better than the prior experimentally and theoretically reported Ho^(3+)-doped InF3 fiber lasers emitting at~3.9μm *** work demonstrates a versatile platform for laser generation at~3.2μm and~3.9μm,thus providing the new opportunities for many potential applications,e.g.,polymer processing,infrared countermeasures,and free-space communications.

关键词： Cascaded Fiber laser Holmium Mid-infrared

Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： ya-zhou Chen Hakho Hong Xiao-ding Shi Department of Mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China Institute of Mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate

In-situ SEM characterization of fracture mechanism of TiB/Ti-2Al-6Sn titanium matrix composites after electroshocking treatment

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Rare Metals 2024年第6期43卷 2805-2818页

作者： ya-ya Wu jian zhou Guo-Lei Han yan Wen zhou Wang Li-Qiang Wang Wei-jie Lv Le-Chun Xie Lin Hua Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In this article,in-situ scanning electron microscope characterization of the tensile properties of TiB/Ti-2Al-6Sn titanium matrix composite(TMC)was conducted before and after electroshocking treatment(EST).After EST,the tensile strength increased by 113.2 *** effect of EST on the tensile strength and fracture behavior of TiB was investigated using in-situ characterization of the fracture morphology and crack propagation path of the matrix and *** EST,TiB fracture introduced cracks that extended into the matrix,resulting in material *** EST,the refined TiB improved the bearing capacity of the matrix,thereby improving TMC ***,after EST,the cracks were introduced into the matrix,and resulting the fracture of matrix *** an increase in the external load,cracks in the matrix were observed to propagate to TiB,and the refined TiB was fractured,detached,and pulled out,resulting in the formation of *** the propagation path of the main crack after EST showed that the deflection angle of the main crack *** micro structure of the fracture surface indicated that the fracture of the matrix was plastic,whereas that of TiB was *** EST,the size and area of the dimples increased,confirming the increase in *** results revealed that the comprehensive mechanical properties of TiB/Ti-2Al-6Sn improved after ***,EST is an efficient method for tailoring the micro structures and mechanical properties of TMCs.

关键词： TiB/Ti-2Al-6Sn In-situ microstructure characterization Tensile properties Reinforcement Electroshocking treatment(EST)

Integrated interconnected porous and lamellar structures realized fast ion/electron conductivity in high-performance lithium-sulfur batteries

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Chinese Chemical Letters 2024年第6期35卷 161-167页

作者： ya Song Mingxia zhou Zhu Chen Huali Nie jiao-j.ng Shao Guangmin zhou School of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Medical College of Guizhou University Guiyang 550025China College of Biological Science and Medical Engineering Donghua UniversityShanghai 201620China Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

The practical application of high-energy-density lithium-sulfur(Li-S)batteries have been highly praised for energy storage devices,while are largely hindered by the“shuttling effect”.Herein,core-shell carbon spheres composed of interlinked porous core and lamellar shell were designed to restrain the polysulfide *** microporous structure with pore size of around 1 nm effectively trap lithium ***,the interconnected porous core shortens the ion transfer distance and the lamellar carbon shell endows the carbon spheres with fast electron conduction,finally facilitating polysulfide conversion ***,the Li-S batteries with the carbon spheres as the interlayer show high discharge specific capacity of 1002 m Ah/g at 2 C with 574 m Ah/g remaining after 600 cycles,and high areal capacity of 5.48 m Ah/cm^(2) with sulfur loading of 4.67 mg/cm^(2) at 0.1 *** corresponding pouch cells also exhibit stable cycling stability with an initial discharge specific capacity of 1082 m Ah/g at 0.1 C.

关键词： Interlayer Shuttle effect Strong adsorption Porous carbon spheres Lithium-sulfur batteries

Cracking on a nickel-based superalloy fabricated by direct energy deposition

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China Foundry 2024年第4期21卷 311-318页

作者： Xue Zhang ya-hang Mu Liang Ma j.ng-j.ng Liang Yi-zhou zhou Xiao-feng Sun jin-guo Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based *** is essential to investigate the location of cracks and their forming *** study extensively examines the impact of solidification process,microstructural evolution,and stress concentration on crack initiation during direct energy deposition(DED).The results emphasize that the crack formation is significantly related to large-angle grain boundaries,rapid cooling *** caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited *** cracks are more likely to form near the top of the deposited sample,due to the presence ofγ/γ'*** secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification,which results in the formation of solidification cracks and *** work paves the way to avoid cracks in nickel-based superalloys fabricated by DED,thereby enhancing the performance of superalloys.

关键词： location cracks direct energy deposition nickel-based superalloys

Regulation of rhizosphere microenvironment by rice husk ash for reducing the accumulation of cadmium and arsenic in rice

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journal of Environmental Sciences 2024年第2期136卷 1-10页

作者： Yi jiang ya Liu Xuantao Yi Peng Zeng Bohan Liao Hang zhou jiaofeng Gu College of Environmental Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China Hunan Engineering Laboratory for Control of Rice Quality and Safety Changsha 410004China

It is important to reduce Cd and As content in brown rice in contaminated paddy *** conducted research on the effects of rice husk ash (RHA) on the Cd and As in the rhizosphere microenvironment (soil,porewater,and iron plaque) and measured the Cd,As,and Si content in rice *** main elements in RHA were Si (29.64%) and O (69.17%),which had the maximum adsorption capacity for Cd was 42.49 mg/kg and for As was 18.62 mg/*** pH and available Si content increased,while soil available Cd and As decreased following application of 0.5%–2%*** promote the transformation of Cd to insoluble fraction,while As was transformed from a poorly soluble form to a more active *** reduced Cd content and increased Si content in porewater,and reduced As only at the later rice growth *** increased the amount of iron plaque,thereby decreasing the Cd content in iron plaque,while increased the As content in *** and inorganic As content in brown rice were decreased,to 0.31 mg/kg and 0.18 mg/kg,*** decrease of Cd in brown rice was due to the decrease of Cd mobility in soil,thereby reducing root accumulation,while the decrease of As in brown rice was affected by the transport from roots to ***,RHA can be considered as a safe and efficient in-situ remediation amendment for Cd and As co-contaminated paddy soil.

关键词： Rice husk ash(rha) Cadmium Arsenic Silicon Rice Soil

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

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Engineering 2024年第7期38卷 144-154页

作者： jun-Su zhou Long Cheng Yuan Gao Zhan-Peng Ge Bin zhou j.ng-ya Li jin-Xin Zhao jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Four new norditerpenoid heterodimers with different dimerization patterns-namely,trigofragiloids A-C(denoted as compounds 1-3)and(+)-and(-)-trigofragiloid D(compound 4)-and three new phenanthrenone norditerpenoids-namely,trigofragiloids E-G(compounds 5-7)-were isolated from Trigonostemon *** 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid;they have been identified as class 2 atropisomers by means of quantum chemical *** 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization ***(+)-and(-)-4 are the first example of S-shaped 1,4-dioxane-fused norditerpenoid *** by the structure elucidation of compound 4,two co-occurring analogues,actephilol A and epiactephilol A,were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers,(+)-and(-)-8 and(+)-and(-)-9,*** structures were characterized using a combined ***,compound 7 exhibits remarkable adenosine triphosphate-citrate lyase(ACLY)inhibition with a halfmaximal inhibition concentration(IC50)value of(0.46±0.11)lmol·L^(-1),as active as the positive control BMS-303141,and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer Trigonostemon fragilis Euphorbiaceae Trigofragiloid Structural revision Adenosine triphosphate-citrate lyase(ACLY) inhibitory activity

Deciphering dynamic surface of PtRu alloy nanocatalysts to revisit their synergistic effects during the electrooxidation

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Science China Chemistry 2024年第7期67卷 2224-2233页

作者： Xiao-Chong Li Bo Wang zhou Yu Qiang Wan ju-Fang Zheng Emmanuel Maisonhaute Xiao-Shun zhou ya-Hao Wang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China Laboratoire Interface et Systèmes Electrochimiques CNRS UMR 8235Sorbonne UniversitéF-75252 Paris cedex 5France

Correlating dynamic structural transformation of catalysts with the surface intermediate species under operating conditions is critical for updating the understanding of structure–performance ***,we probe the electrochemical potentialdependent surface structures and adsorbed intermediates on PtRu binary alloy nanocatalysts to revisit its synergistic mechanisms for CO electrooxidation enhanced ***-situ spectral characteristics by using modified shell-isolated nanoparticle-enhanced Raman spectroscopy,show that in acidic solution,when the potential is positively scanned from 0.1 V to 1.5 V relative to reversible hydrogen electrode(RHE),the surface of the alloy catalyst evolves from metallic PtRu to adsorbed oxygen gradually covering and accumulating on Ru sites(denoted as PtRuO_(x),x≤2),forming segregated RuO_(2),and finally forming a threedimensional oxide layer(denoted as 3D PtRuO_(4)).Moreover,molecular evidence associated with periodic density functional theory calculations reveals that electronic effects promote ruthenium to become more oxidizable and *** particular,we found here that ^(*)O and ^(*)OH at surface RuO_(x) sites are highly efficient CO oxidation active species in comparison to the same entities adsorbed on metallic Ru *** work sheds light on the complex surface dynamic process of practical Pt-based binary nanocatalysts and improves the understanding of synergistic mechanism for the development of fuel cell devices.

关键词： in-situ Raman spectroscopy surface evolution bifunctional mechanism PtRu electrooxidation

Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

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Chinese journal of Integrative Medicine 2024年第4期30卷 299-310页

作者： LIU Xiao-rong LI Shuo-fu MEI Wen-ya LIU Xiang-dan zhou Ri-bao College of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China Department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS ***-FLS viability,migration,and invasion were ***,a collagen-induced arthritis(CIA)rat model was *** were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,*** index was calculated and synovial tissue inflammation was determined in CIA *** levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial *** docking was also used to analyze the binding of isorhamnetin to *** In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(P<0.05).Isorhamnetin downregulated the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1βin RA-FLS(P<0.05).The overexpression of either MMP2 or MMP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion,as well as the levels of TNF-α,IL-6,and IL-1β(P<0.05).Furthermore,isorhamnetin bound to SRC and reduced the phosphorylation of SRC,ERK,and CREB(P<0.05).SRC overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability,migration and invasion,as well as the negative regulation of MMP2 and MMP9(P<0.05).In in vivo studies,isorhamnetin decreased arthritis index scores(P<0.05)and alleviated synovial *** reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CRE

关键词： rheumatoid arthritis isorhamnetin SRC/ERK/CREB matrix metalloproteinase