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Journal of Iron and Steel Research International 2023年第4期30卷 795-807页

作者： Cheng-song Liu Wei Liu Hua zhang hong-wei Ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Transformation mechanisms and reaction kinetics for formation of nanoscale inclusions in as-built 316L stainless steel produced by laser beam powder bed fusion(LB-PBF)during subsequent isothermal heating process were investigated and clarified experimentally and *** resulting changes in morphologies,size distributions,number densities,and chemical compositions of the inclusions were measured and discussed,along with microstructure and texture of the *** results showed that with increasing isothermal heating time and temperature,the columnar grains in the as-built LB-PBF 316L stainless steel transformed into equiaxed grains,which grew gradually and exhibited a large number of twins in the FCC *** isothermal heating,the reaction of Si in the steel with MnO–Cr_(2)O_(3)in the nanoscale inclusion resulted in a transformation from the homogeneous oxide MnO–SiO_(2)–Cr_(2)O_(3)to an inclusion with an obvious core–shell structure,and the core part was eventually rich in Si and the shell part was predominantly rich in Mn and Si,depending on the heating temperature and *** Ostwald ripening model used for predicting the growth of nanoscale inclusions during isothermal heating verified that the observed effects of isothermal heating time and temperature were predicted for Si diffusion control.

关键词： 316L stainless steel Laser beam powder bed fusion Nanoscale inclusion Isothermal heating Transformation

Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 46-51页

作者： Yiying Zhu Hesong Wang Anzhi zhang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Forestry and Landscape Architecture Xinjiang Agricultural UniversityUrumqiChina

Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of *** the same time,detailed accounts of disturbances and forest responses are not yet well quantified in *** study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast *** approach allowed us to detect forest disturbance and quantify the resilience after *** showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by ***,95%of forests had robust resilience and could recover from disturbance within a few *** resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance *** summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two *** authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in *** findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing.

关键词： Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method Disturbance Resilience

Molecular mechanism of the inhibition effect of Celecoxib on corneal collagen degradation in three dimensions

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International Journal of Ophthalmology(English edition) 2012年第4期5卷 434-439页

作者： Wen-song zhang, hong-Yan Zhou Department of Ophthalmology the Second Hospital of Jilin University Changchun 130041 Jilin Province China Department of Ophthalmology China-Japan Union Hospital of Jilin University Changchun 130033 Jilin Province China

AIM: To clarify the molecular mechanism of Celecoxib on corneal collagen degradation and corneal ulcer. METHODS: Rabbit corneal fibroblasts were harvested and suspended in serum-free MEM. Type I collagen, DMEM, collagen reconstitution buffer and corneal fibroblast suspension were mixed on ice. The resultant mixture solidify in an incubator, after which test reagents and plasminogen was overlaid and the cultures were returned to the incubator. The supernatants from collagen gel incubations were collected and the amount of hydroxyproline in the hydrolysate was measured. Immunoblot analysis of MMP1, 3 and TIMP1, 2 was performed. MMP2, 9 was detected by the method of Gelatin zymography. Cytotoxicity Assay was measured. RESULTS: Celecoxib inhibited corneal collagen degradation in a dose and time manner; Celecoxib inhibited the IL-1 beta induced increases in proMMP1, 2, 3, 9 and active MMP1, 2, 3, 9 in a concentration-depended manner. Celecoxib can also inhibit the IL-1 beta induced increases in the TIMP1, 2. CONCLUSION: Celecoxib can inhibit corneal collagen degradation induced by IL-1 beta, this effect is the consequence of the reduction of MMP1, 2, 3, 9 and TIMP1, 2. The results of the present study provide new insight into Celecoxib in cornela ulcer treatment.

关键词： Celecoxib corneal ulcer IL-1β collagen degradation

Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng Hai-Hui Jiang Hui-Li Kang Yi Jiang Hua-Wei zhang Xiao-Mei song Yu-Ze Li Wen-Li Huang Dong-Dong zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

Magnetic field annealing of FeCo-based amorphous alloys to enhance thermal stability and Curie temperature

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Rare Metals 2023年第6期42卷 2000-2006页

作者： Zai-Dao Li Wei-Wei zhang Ge-Tian Li song-song Li hong-Sheng Ding Tao zhang Yu-Jun song Center for Modern Physics Technology Department of Applied PhysicsBeijing Key Laboratory for Magneto-Photoelectrical Composite and Interface ScienceUniversity of Science and Technology BeijingBeijing100083China School of Materials Science and Engineering Beihang UniversityBeijing100191China

Annealing temperatures and applied magnetic fields are two important parameters for the performance modification of magnetic *** article investigated the effect of different annealing temperatures on crystallization condition,magnetic properties and thermal stability of the amorphous magnetic alloy Co_(36)Fe_(36)Si_(4.8)B1_(9.2)Nb_(4)(at%).Results indicate that the annealing temperature can significantly affect the size and content of precipitated nanocrystals in the amorphous alloy,and the precipitation of nanocrystalline phases can result in the distinct change of magnetic properties and Curie *** the annealing was performed at 595 ℃ for 30 min under an applied transverse external magnetic field of 9550.0A·m^(-1),the amorphous alloy shows excellent soft magnetic properties with the saturation magnetization of alloy reaching 110.00 mA·m^(2)·g^(-1),the residual magnetic induction intensity of 4 × 10^(-6) T and the coercivity as low as57.3 A·m^(-1).Furthermore,the Curie temperature of the field-annealed samples can reach up to 440 0C,approximately 58℃ higher than that of the as-quenched species.

关键词： Soft magnetic alloys Amorphous alloy Field annealing

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou zhang Shuo Li Fu Tang Jingkai zhang Yuetong Kang Hean zhang Lidong Li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

Novel High-Order Mass-and Energy-Conservative Runge-Kutta Integrators for the Regularized Logarithmic Schrodinger Equation

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Numerical Mathematics(Theory,Methods and Applications) 2023年第4期16卷 993-1012页

作者： Xu Qian hong zhang Jingye Yan songhe song Department of Mathematics National University of Defense TechnologyChangsha 410073China College of Mathematics and Physics Wenzhou UniversityWenzhou 325000China

We develop a class of conservative integrators for the regularized logarithmic Schrodinger equation(RLogSE)using the quadratization technique and symplectic Runge-Kutta *** preserve the highly nonlinear energy functional,the regularized equation is first transformed into an equivalent system that admits two quadratic invariants by adopting the invariant energy quadratization *** reformulation is then discretized using the Fourier pseudo-spectral method in the space direction,and integrated in the time direction by a class of diagonally implicit Runge-Kutta schemes that conserve both quadratic invariants to round-off *** comparison purposes,a class of multi-symplectic integrators are developed for RLogSE to conserve the multi-symplectic conservation law and global mass conservation law in the discrete *** experiments illustrate the convergence,efficiency,and conservative properties of the proposed methods.

关键词： Regularized logarithmic Schrödinger equation conservative numerical integrators invariant energy quadratization approach diagonally implicit Runge-Kutta scheme

Developments of New Sheet Metal Forming Technology and Theory in China

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1452-1470页

作者： Shi-hong zhang Shuai-Feng Chen Yan Ma hong-Wu song Ming Cheng Institute of Metal Research Chinese Academy of Sciences

Developments of new sheet metal forming technology and theory in China are reviewed in detail in this *** of crystal plasticity on the deformation mechanism of Mg alloy are firstly described, especially its applications on the prediction of sheet forming process. Then, a new macroscopic constitutive model is introduced, which possesses an enhanced description capacity of tension/compression anisotropy and anisotropic hardening. In order to take into account the twinning process of hexagonal close-packed material, a modified hierarchical multi-scale model is also established with adequate accuracy in a shorter computational time. The advanced forming limit of sheet metal, mainly about aluminum alloy, is also investigated. Besides the above theory developments, some new sheet metal forming technologies are reviewed simultaneously. The warm forming technology of Mg alloy is discussed. New processes to form sheet parts and to bend tubes are proposed by using hard granules. On the other hand, a new kind of ultra-high-strength steel based on typical22 Mn B5 by introducing more residual austenite and Cu-rich phase to increase the elongation and strength and its novel forming method that integrates hot stamping and quenching participation are proposed. Progresses in sheet hydroforming,press forging and electromagnetic forming of sheet metal parts are also summarized.

关键词： Sheet forming Crystal plasticity Constitutive modeling Mg alloy UHSS Hot stamping Hydroforming Aluminum alloy

Deformation Mechanism of AZ31B Magnesium Alloy Under Different Loading Paths

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1426-1434页

作者： Shuai-Feng Chen Li Zheng Shi-hong zhang hong-Wu song Ming Cheng Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering Shenyang University of Technology

Deformation and texture evolution of AZ31 B magnesium（Mg） alloy sheet under uniaxial tension, compression, and reverse loading after different pre-strain（compression and tension） were investigated experimentally. The results indicate that the pre-compressive strain remarkably affects the reverse tensile yield stress and the width of the detwinning-dominant stage during inverse tension process. Similar to stress–strain curve of the uniaxial compression, the curve of reverse tensile yield value also has ‘S＇ shape, and its minimum value is only 38 MPa. The relationship between pre-compressive strain and the width of detwinning-dominant stage presents a linear growth, and the greater the precompressive strain is, the smaller the strain hardening rate of the detwinning-slip-dominant stage is. Compared with the reverse tension under pre-compression, the influence of the pre-tension deformation on the deformation mechanism of subsequent compression is relatively simple. With the increase in pre-tension strain, the yield stress of the reverse loading is rising.

关键词： AZ31B magnesium alloy Loading path Detwinning Texture Yield stress

Global Existence and Asymptotic Behavior of Solutions to a Free Boundary Problem for the 1D Viscous Radiative and Reactive Gas

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Acta Mathematica Sinica,English Series 2018年第5期34卷 827-842页

作者： Chang Ming song hong LI Jian Lin zhang Department of Applied Mathematics College of Science Zhongyuan University of Technology Zhengzhou 450007 P. R. China Department of Applied Physics College of Science Zhongyuan University of Technology Zhengzhou 450007 P. R. China

In this paper, we study a free boundary problem for the 1D viscous radiative and reactive gas. We prove that for any large initial data, the problem admits a unique global generalized solution. Meanwhile, we obtain th... 详细信息

关键词： Radiative and reactive gases global solution free boundary problem asymptotic behavior