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Effects of annealing treatment on microstructure and tensile behavior of the Mg-Zn-Y-Nd alloy

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Journal of Magnesium and Alloys 2020年第3期8卷 601-613页

作者： L.Y.Sheng B.N.Du Z.Y.Hu Y.X.Qiao Z.P.xiao B.J.Wang D.K.Xu Y.f.Zheng t.f.xi Shenzhen Institute Peking UniversityShenzhen 518057China Jiangsu University of Science and technology Zhenjiang 212003China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China dShenzhen Yezhan Electronics Co. LtdShenzhen 518110China

In the present study,the Mg-4Zn-0.6Y-0.5Nd alloy was hot extruded and annealed at 200℃,225℃ and 250℃ for different time to optimize microstructure and mechanical *** results exhibit that the dual-size grain structure and linearly distributed secondary phase are the main feature of the as-extruded Mg-Zn-Y-Nd alloy,which can be described as the elongated grain is surrounded by the fine equiaxed ***,the as-extruded alloy shows strong{011^(-)0}fiber texture feature,especially for the large elongated *** annealing treatment results in static recrystallization,which increases fine equiaxed grains but decreases large elongated *** addition,the equiaxed grains formed during the annealing treatment demonstrate relative random orientations,which weaken the{011^(-)0}fiber texture of the ***,during the annealing at 225℃and 250℃,the extension twins begin to form in the alloy and weaken the{011^(-)0}fiber texture of the alloy *** annealing treatment has little influence on the linearly distributed secondary phase but promotes the coarsening of small precipitates at 250℃.the annealing treatment could increase the yield and ultimate strength,but the elongation decreases,especially at higher *** a variation can be ascribed to the evolution of texture,grain structure,twinning and precipitation during the annealing treatment.

关键词： Annealing treatment Mg-Zn-Y-Nd alloy Microstructure tensile property

Investigation on B, Cr Doped Ni3Al Alloy Prepared by Self- Propagation High-temperature Synthesis and Hot Extrusion

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Investigation on B, Cr Doped Ni3Al Alloy Prepared by Self- P...

Parameter-free Shifted Laplacian Reconstruction for Multiple Kernel Clustering

中国材料大会2012

作者： L.Y.Sheng J.t.Guo C.Yuan f.Yang G.S.Li t.f.xi Shenzhen Institute Peking University College of Engineering Peking University Shenzhen Airlines Shenzhen Bao’an International Airport Institute of Metal Research Chinese Academy of Sciences

ISBN: (纸本)9783037856086;3037856084

the Ni3Al and Ni3Al-B-Cr alloys were fabricated by the self-propagation high-temperature synthesis with hot extrusion method. their microstructure and mechanical properties were studied by using combination of X-ray diffraction, optical microscopy, transmission electron microscopy and compression test. Analysis of X-ray spectra exhibited that the elemental powders had been transformed to the Ni3Al phase after the self-propagation high-temperature synthesis processing. Microstructure examination showed that the alloy without extrusion consisted of coarse and fine grains, but the subsequent hot extrusion procedure homogenized the grain size and densified the alloy obviously. transmission electron microscopy observations on the Ni3Al alloy revealed that Ni3Al, γ-Ni and Al2O3 particles were the main phases. When the boron and chromium were added, besides the β-NiAl phase, α-Cr phase and some Cr7Ni3 particles with stacking faults inside were observed. In addition, a lot of substructure and high-density dislocation arrays were observed in the extruded part, which indicated that the subsequent extrusion had led to great deformation and partly recrystallizing in the alloy. Moreover, the subsequent extrusion procedure redistributed the Al2O3 particles and eliminated the γ-Ni. these changes were helpful to refine the microstructure and weaken the misorientation. the mechanical test showed that the self-propagation high-temperature synthesis with hot extrusion improved the mechanical properties of the Ni3Al alloy significantly. the addition of B and Cr in Ni3Al alloy increased the mechanical properties further, but the compressive strength of the alloy was still lower than that synthesized by combustion. finally, the self-propagation high-temperature synthesis with hot extrusion was a good method to prepare Ni3Al alloy from powder.

关键词： Ni3Al Self-propagation high-temperature synthesis Extrusion Microstructure Mechanical properties

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： xi Wu Zhenwen Ren f.Richard Yu the School of National Defence Science and technology Southwest University of Science and TechnologyMianyang 621010China the School of National Defence Science and technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,this letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian.

关键词： parameter letter Parameter

Variational Analysis Based on Proximal Subdifferential on Smooth Banach Spaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 595-618页

作者： xi Yin ZHENG Department of Mathematics Yunnan UniversityKunming 650091P.R.China

this paper first shows that for any p∈(1,2)there exists a continuously differentiable function f on l^(p)(and L^(p))such that the proximal subdifferential of f is empty everywhere,and hence it is not suitable to develop theory on proximal subdifferential in the classical Banach spaces l^(P)and L^(P) with p∈(1,2).On the other hand,this paper establishes variational analysis based on the proximal subdifferential in the framework of smooth Banach spaces of power type 2,which conclude all Hilbert spaces and all the classical spaces l^(P)and L^(P)with p∈(2,+∞).In particular,in such a smooth space,we provide the proximal subdifferential rules for sum functions,product functions,composite functions and supremum functions,which extend the basic results on the proximal subdifferential established in the framework of Hilbert *** of our main results are new even in the Hilbert space *** applications,we provide KKt-like conditions for nonsmooth optimization problems in terms of proximal subdifferential.

关键词： Smooth Banach space proximal subdifferential proximal normal cone KKt condition

Homological transfer between Additive Categories and Higher Differential Additive Categories

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1325-1344页

作者： xi tANG Zhao Yong HUANG School of Science Guilin University of Aerospace TechnologyGuilin 541004P.R.China Department of Mathematics Nanjing UniversityNanjing 210093P.R.China

Given an additive category C and an integer n≥*** higher differential additive category consists of objects X in C equipped with an endomorphism ϵ_(X)satisfying ϵ_(X)^(n).Let R be a,finite-dimensional basic algebra over an algebraically closed field and t the augmenting functor from the category of finitely generated left R-modules to that of finitely generated left R/(t^(n))-*** is proved that a finitely generated left R-module M isτ-rigid(respectively,(support)τ-tilting,almost completeτ-tilting)if and only if so is t(M)as a left R[t]/(t^(n))-***,R isτm-selfinjective if and only if so is R[t]/(t^(n)).

关键词： Higher differential objects Wakamatsu tilting subcategories G_(ω)-projective modules sup-portτ-tilting modules τ_(m)-selfinjective algebras precluster tilting subcategories

traditional Chinese Medicine Integrated Responsive Microneedles for Systemic Sclerosis treatment

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Research 2024年第1期2023卷 139-147页

作者： xi Luan xiaoxuan Zhang Min Nie Yuanjin Zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of PharmacyClinical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

traditional Chinese medicine,such as tripterygium wilfordii and Paeonia lactiflora,has potential values in treating systemic sclerosis(SSc)and other autoimmune diseases,while their toxic side effect elimination and precise tropical drug delivery are still ***,we present multiple traditional Chinese medicine integrated photoresponsive black phosphorus(BP)microneedles(MNs)with the desired features for the SSc *** employing a template-assisted layer-by-layer curing method,such MNs with triptolide(tP)/paeoniflorin(Pae)needle tips and BP-hydrogel needle bottoms could be well *** combined administration of tP and Pae can not only provide anti-inflammatory,detoxification,and immunomodulatory effects to treat skin lesions in the early stage of SSc but also remarkably reduce the toxicity of single drug ***,the additive BPs possess good biocompatibility and near-infrared(NIR)responsiveness,imparting the MN photothermal-controlled drug release *** on these features,we have demonstrated that the traditional Chinese medicine integrated responsive MNs could effectively improve skin fibrosis and telangiectasia,reduce collagen deposition,and reduce epidermal thickness in the SSc mouse *** results indicated that the proposed Chinese medicine integrated responsive MNs had enormous potential in clinical therapy of SSc and other diseases.

关键词： needle precise template

B-cell lymphoma-2 phosphorylation at Ser70 site-related autophagy mediates puerarin-inhibited the apoptosis of MC3t3-E1 cells during osteoblastogenesis

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Journal of traditional Chinese Medicine 2024年第1期44卷 27-34页

作者： LI xi LIN xiangquan CHEN Dongdong LIU Hui the third Clinical Medical College Fujian Medical University Department of Orthopedics Fuzhou Second HospitalFuzhou 350007China

OBJECtIVE:to explore the relationship between autophagy and apoptosis regulated by puerarin during ***:In this study,the effects of puerarin on the autophagic activity and apoptosis level of osteoblast precursors(MC3t3-E1 cells)was ***,the roles of puerarin on B-cell lymphoma-2(Bcl-2)phosphorylation at different sites in osteoblast precursors were *** effect of puerarin on the interaction between Bcl-2 and autophagy regulatory molecule or pro-apoptotic molecule was also investigated using Co-immunoprecipitation *** addition,the effect of puerarin on mitochondrial membrane potential of osteoblast precursors was also identified by mitochondrial membrane potential fluorescence probe ***:Our results showed that puerarin can promote the autophagic activity and apoptosis level of *** addition,puerarin promoted Bcl-2phosphorylation at Ser70 site,and the dissociation of Bcl-2-Beclin1 ***,puerarin could enhance the binding of Bcl-2-Bcl-2-Associated X(Bax)complex in MC3t3-E1 ***,puerarin increased the mitochondrial membrane potential of MC3t3-E1 ***:therefore,puerarin promotes Beclin1into autophagy flux through Bcl-2 phosphorylation at Ser70,thereby enhancing autophagy of osteoblast precursors,which mediates its anti-apoptotic role during ***,the dissociation of Bcl-2-Beclin1 complex is conducive to the binding of Bcl-2-Bax complex,which resists the apoptosis of osteoblast precursors via the increased mitochondrial membrane potential.

关键词： puerarin osteoblasts autophagy apoptosis lymphoma B-cell

Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： Lei Wan Yizhou tong xi Lu Yao fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Colloid-facilitated release of polybrominated diphenyl ethers at an e-waste recycling site: evidence from undisturbed soil core leaching experiments

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frontiers of Environmental Science & Engineering 2024年第2期18卷 91-101页

作者： Zebin Huo Mengjun xi Lianrui Xu Chuanjia Jiang Wei Chen College of Environmental Science and Engineering Ministry of Education Key Laboratory of Pollution Processes and Environmental CriteriaTianjin Key Laboratory of Environmental Remediation and Pollution ControlNankai UniversityTianjin 300350China

Polybrominated diphenyl ethers (PBDEs), a class of persistent organic pollutants, have been frequently detected in soil at e-waste recycling sites. However, the key factors controlling the transport of PBDEs from surface soil to the vadose zone and groundwater are unclear. Here, colloid-enhanced leaching of PBDEs from undisturbed soil cores collected at an e-waste recycling site in tianjin, China, is reported. Spatially heterogeneous release of colloids and PBDEs was observed in all the tested soil cores under chemical and hydrodynamic perturbations, indicating the presence of preferential flow paths. Colloid concentration in the effluent significantly increased as ionic strength decreased (from 10 to 0.01 mmol/L), probably due to the stronger electrostatic repulsion between colloidal particles and the soil matrix at lower ionic strength. In contrast, colloid mobilization was not significantly affected by the changes in pH of the influent (from 4.0 to 10.0) and flow rate (from a Darcy velocity of 1.5 to 6.0 cm/h). the concentrations of 2,2′,3,3′,4,4′,5,5′,6,6′-decabromodiphenyl ether (BDE-209), the predominant PBDE congener at the site, detected in the leachate (ranging from 1.09 to 3.43 ng/L) were much lower than previously reported results from packed column leaching tests, and were positively correlated with colloid concentrations. this indicates that remobilization of colloids at e-waste recycling sites can promote the leaching and downward migration of PBDEs from surface soil. the findings highlight the potential risk of surface soil PBDE contamination to groundwater quality and call for further understanding of colloid-facilitated transport for predicting the fate of PBDEs at e-waste recycling sites.

关键词： Polybrominated diphenyl ether Colloid-facilitated transport E-waste recycling site Undisturbed soil core Groundwater quality