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聚甲醛(POM)纤维自密实混凝土(SCC)工作性和力学性能研究
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作者 贺晶晶 卢浩丹 +3 位作者 王攀菲 陈凌威 胡炜 吴文博 《混凝土与水泥制品》 2026年第1期37-42,共6页
研究了聚甲醛(POM)纤维的形状(圆柱状、扁平状)、长度(8 mm、12 mm)和掺量(0.8、1.2、1.6、2.0 kg/m^(3))对自密实混凝土(SCC)工作性和力学性能的影响。结果表明:POM纤维对SCC工作性的影响较小;随着POM纤维的掺量从0.8 kg/m^(3)增至2.0 ... 研究了聚甲醛(POM)纤维的形状(圆柱状、扁平状)、长度(8 mm、12 mm)和掺量(0.8、1.2、1.6、2.0 kg/m^(3))对自密实混凝土(SCC)工作性和力学性能的影响。结果表明:POM纤维对SCC工作性的影响较小;随着POM纤维的掺量从0.8 kg/m^(3)增至2.0 kg/m^(3),SCC的坍落扩展度、抗压强度和轴压强度均呈先升高后降低的趋势,T_(50)先降低后升高,抗折强度、轴拉强度和弹性模量均呈逐渐增大的趋势;总体上,当POM纤维掺量为1.2 kg/m^(3)时,对SCC工作性和力学性能的提升效果最好;与扁平状POM纤维相比,圆柱状POM纤维相对更适合掺入SCC中;考虑SCC工作性、抗压强度和轴压强度时,建议掺入8 mm长圆柱状POM纤维;考虑SCC轴拉强度和弹性模量时,建议掺入12 mm长圆柱状POM纤维。 展开更多
关键词 自密实混凝土(SCC) pom纤维 工作性 力学性能 纤维形状 纤维掺量 纤维长度
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Facile synthesis of Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)solid solutions for improving photocatalytic CO_(2)reduction
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作者 WANG Jingzhou YAO Chenzhong +2 位作者 ZHANG Xisheng MA Ziwei LI Linfeng 《燃料化学学报(中英文)》 北大核心 2026年第1期15-25,共11页
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce... In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal method optical response range solid solution charge separation
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All Non-Commuting Solutions of the Yang-Baxter-like Matrix Equation Which Coefficient Matrix is Similar to diag(λ,J_(2)(λ))
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作者 WANG Yun-jie 《Chinese Quarterly Journal of Mathematics》 2026年第1期92-110,共19页
Let A be a 3×3 singular or diagonalizable matrix,all solutions to the Yang-Baxter-like matrix equation have been determined.However,finding all solutions for full rank,non-diagonalizable matrices remains challeng... Let A be a 3×3 singular or diagonalizable matrix,all solutions to the Yang-Baxter-like matrix equation have been determined.However,finding all solutions for full rank,non-diagonalizable matrices remains challenging.By utilizing classification techniques,we establish all solutions of the Yang-Baxter-like matrix equation in this paper when the coefficient matrix A is similar to non-diagonalizable matrix diag(λ,J_(2)(λ))withλ̸=0.More specifically,we divide the non-diagonal elements of the solution into 10 different cases.By discussing each situation,we establish all solutions of the Yang-Baxter-like matrix equation.The results of this work enrich the existing ones. 展开更多
关键词 Yang–Baxter–like matrix equation Yang–Baxter equation Commuting solutions Non–commuting solutions
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GLOBAL STRONG SOLUTIONS TO THE PLANAR COMPRESSIBLE MAGNETOHYDRODYNAMIC EQUATIONS WITH DEGENERATE HEAT-CONDUCTIVITY IN THE HALF-LINE
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作者 Mengdi TONG Xue WANG Rong ZHANG 《Acta Mathematica Scientia》 2026年第1期189-208,共20页
This paper is concerned with an initial boundary value problem for the planar magnetohydrodynamic compressible flow with temperature dependent heat conductivity in a half-line.In particular,the transverse magnetic fie... This paper is concerned with an initial boundary value problem for the planar magnetohydrodynamic compressible flow with temperature dependent heat conductivity in a half-line.In particular,the transverse magnetic field is assumed to satisfy the Neumann boundary condition,which was first investigated by Kazhikhov in 1987.We establish the global existence of the unique strong solutions to the MHD equations without any smallness conditions on the initial data.More precisely,our result can be regarded as a natural generalization of Kazhikov’s result for applying the constant heat-conductivity in bounded domains to the degenerate case in unbounded domains. 展开更多
关键词 MAGNETOHYDRODYNAMICS temperature-dependent heat conductivity global strong solutions HALF-LINE
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Existence,Uniqueness and Stability of Bounded Solutions for Minkowski-Curvature Problems with Asymptotic Boundary Conditions
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作者 Tianlan CHEN Xuying TANG 《Journal of Mathematical Research with Applications》 2026年第1期57-70,共14页
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→... In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions. 展开更多
关键词 mean curvature operator UNIQUENESS asymptotic boundary conditions bounded solution
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Solution set of circumlunar abort trajectory and its direct application to optimization design
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作者 Tianshan DONG Zhen HUANG +2 位作者 Wenyan ZHOU Xiangyu ZHANG Lin LU 《Chinese Journal of Aeronautics》 2026年第1期333-348,共16页
Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar... Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar abort trajectory and leverages its advantageous properties to address the optimization design problem of abort trajectories.Initially,a solution set of all feasible abort trajectories,originating from an abort point on the nominal trajectory and complying with fundamental reentry constraints,is formulated through the introduction of two novel design parameters.Subsequently,the geometric characteristics of the solution set,as well as the distributional properties of key iterative constraint responses,including flight time and velocity increment,are analyzed.Finally,the characteristics exhibited in the solution set are employed to directly identify the design parameters of the abort trajectories with minimum flight time and velocity increment,thereby providing solutions to two distinct types of optimization problems.The simulation results for a variety of nominal trajectories,encompassing the reconstruction and redesign of the Apollo13 abort trajectory,validate the proposed method,demonstrating its ability to directly generate optimal abort trajectories.The method proposed in this paper investigates feasible abort trajectories from a global perspective,providing both a framework and convenience for mission planning and iterative optimization in abort trajectory design. 展开更多
关键词 Circumlunar abort trajectory Design parameters Geometric characteristics Optimization problems solution set
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Optimal combination of substrate supply amount coupled with nutrient solution management program for cucumber planting
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作者 Zhen Kang Zhaoxi Jiang +5 位作者 Zhaolong Liu Peng Wang Caihong Zhang Maozhou Yuan Mengqi Bai Xiaohui Hu 《Horticultural Plant Journal》 2026年第1期136-148,共13页
Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development... Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development of mechanization,wide-row spacing substrate cultivation became an optimize mode of the greenhouse cucumber cultivation,aligning with the trend of intelligent agriculture.To determine the optimal nutrient solution supply amount(NS)and supply frequency(SF)for promoting the integrated growth of cucumber under wide-row spacing substrate cultivation,we explored the effects of substrate supply amount(SS),NS,and SF on cucumber yield,quality,and element utilization efficiency.A five-level quadratic orthogonal rotation combination design with three experimental factors(NS,SF,and SS)was implemented for 23 coupling treatments over three growing seasons,including spring(2022S and 2023S)and autumn(2022A).The technique for order preference by similarity to ideal solution(TOPSIS)combining weights based on game theory was applied to construct cucumber comprehensive growth evaluation model.Single and two experimental factors analyses revealed significant effects of single factors and the coupling of NS-SS,NS-SF and SS-SF on the integrated growth of cucumber for all three growing seasons.For the NS-SF-SS combination,the optimal parameters for comprehensive cucumber growth were determined as follows:levels of^(-1).68 for NS,-0.7 for SF,and^(-1).682 for SS in 2022A;-0.43 for NS,-0.06 for SF,and 0.34 for SS in 2022S;0.3 for NS,-0.02 for SF,and 0.04 for SS in 2023S.Furthermore,for SS ranges of 2.00-3.01,3.01-4.50,4.50-5.99,5.99-7.00(L·plant^(-1)),the corresponding NS and SF intervals maximizing cucumber integrated growth in spring were:0.28-0.30(L·plant^(-1))and 6(times·d^(-1)),0.26-0.30(L·plant^(-1))and 6(times·d^(-1)),0.25-0.30(L·plant^(-1))and 6(times·d^(-1)),0.23-0.30(L·plant^(-1))and 6(times·d^(-1)),respectively.With the same SS,the corresponding NS and SF intervals that maximized cucumber integrated growth in autumn were:0.10(L·plant^(-1))and 8(times·d^(-1)),0.18(L·plant^(-1))and 7(times·d^(-1)),0.30(L·plant^(-1))and 6(times·d^(-1)),0.49(L·plant^(-1))and 5(times·d^(-1)),respectively.The results provide a theoretical basis for solution management,and further in-depth research on cucumber cultivation. 展开更多
关键词 Cucumis sativus L. Comprehensive growth Irrigation frequency Nutrient solution Substrate supply amount Wide row spacing
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Synthesis and Magnetic Properties of Mn/Fe/Co Binary Solid Solution in the A-site of V_(2)SnC-MAX Phases
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作者 YAN Ming DENG Yuxiao +2 位作者 YAN Zhuanlong LI Hongyu CAO Mengyang 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期353-363,共11页
This study reported the synthesis of magnetic solid solutions V2(A_(x)B_(y)Sn_(1-x-y))C(where A and B are Mn,Fe,or Co)MAX phases.These materials were prepared by incorporating magnetic elements into the V_(2)SnC MAX p... This study reported the synthesis of magnetic solid solutions V2(A_(x)B_(y)Sn_(1-x-y))C(where A and B are Mn,Fe,or Co)MAX phases.These materials were prepared by incorporating magnetic elements into the V_(2)SnC MAX phase via pressure-less sintering at 1000℃for 3 hours.XRD analysis reveals that the composition with x=y=0.2 exhibits a shift of diffraction peaks to higher angles,indicating lattice parameter changes,and achieves the highest phase purity with the maximum solid solution limit,further increases in the dopant content led to the formation of impurities.While the solid solution of magnetic elements preserves the characteristic layered structure of the MAX phase,it successfully induces magnetic properties.The magnetic transition temperatures for these solid solutions ranges from 61 to 200 K.Specifically,V_(2)(Mn_(x)Co_(y)Sn_(1-x-y))C demonstrated hard magnetic characteristics,with a high saturation magnetization(6.536 emu/g)and large remanence(4.236 emu/g).In contrast,V_(2)(Mn_(x)Fe_(y)Sn_(1-x-y))C and V2(Fe_(x)Co_(y)Sn_(1-x-y))C exhibits soft magnetic behavior,evidenced by their narrow hysteresis loops and low coercivity.Their saturation magnetization values are 3.80 and 1.784 emu/g,respectively.The distinctly"S"-shaped hysteresis loop of V_(2)(Fe_(x)Co_(y)Sn_(1-x-y))C further confirms its soft magnetic nature. 展开更多
关键词 V2SnC solid solution pressure less sintering magnetic MAX phase density functional theory
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Tailoring oxygen vacancies in Ni-doped In_(2)O_(3) for improved thin-film transistor stability and performance via solution processing
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作者 Fakhari Alam Sara Ajmal +3 位作者 Muhammad Asim Shahzad Ghulam Dastgeer Aamir Rasheed Gang He 《Journal of Semiconductors》 2026年第2期61-71,共11页
Doping in thin-film transistors(TFTs) plays a crucial role in tailoring material properties to enhance device performance, making them essential for advanced electronic applications. This study explores the synthesis ... Doping in thin-film transistors(TFTs) plays a crucial role in tailoring material properties to enhance device performance, making them essential for advanced electronic applications. This study explores the synthesis and characterization of TFTs fabricated using nickel(Ni)-doped indium oxide(In_(2)O_(3)) via a wet-chemical approach. The presented work investigates the effect of "Ni" incorporation in In_(2)O_(3) on the structural and electrical transport properties of In_(2)O_(3), revealing that higher "Ni" content decreases the oxygen vacancies, leading to a reduction in leakage current and a forward shift in threshold potential(V_(th)).Experimental findings reveal that Ni In O-based TFTs(with Ni = 0.5%) showcase enhanced electrical performance, achieving mobility of 7.54 cm^(2)/(V·s), an impressive ON/OFF current ratio of ~10^(7), a V_(th) of 6.26 V, reduced interfacial trap states(D_(it)) of 8.23 ×10^(12) cm^(-2) and enhanced biased stress stability. The efficacy of "Ni" incorporation is attributed to the upgraded Lewis acidity, stable Ni-O bond strength, and small ionic radius of Ni. Negative bias illumination stability(NBIS) measurements further indicate that device stability diminishes with shorter light wavelengths, likely due to the activation of oxygen vacancies. These findings validate the solution-processed techniques' potential for future large-scale, low-cost, energy-efficient, and high-performance electronics. 展开更多
关键词 thin-film transistors Ni-doped In_(2)O_(3) solution processing bias illumination stability
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Opportunities of the Integration Between Low-altitude Economy and Commercial Aerospace and Chinese Solutions
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作者 Zhang Mengting Chen Chenggang 《China's Foreign Trade》 2026年第1期45-47,共3页
The 15th Five-Year Plan will begin in 2026,amid heightened global technological competition and rapid supply chain changes.At this pivotal moment,the low-altitude economy and commercial aerospace,once seen as futurist... The 15th Five-Year Plan will begin in 2026,amid heightened global technological competition and rapid supply chain changes.At this pivotal moment,the low-altitude economy and commercial aerospace,once seen as futuristic,are quickly transitioning from strategic concepts to large-scale manufacturing industries.These sectors now drive China’s high-quality development and support a new framework for international engagement. 展开更多
关键词 framework international engagement supply chain Chinese solutions commercial aerospaceonce th five year plan global technological competition low altitude economy lowaltitude economy
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In-situ stress solution theory for borehole overcoring technique incorporating time-dependent effect of stress relief and its applications
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作者 Daohong Xia Shengjun Miao +5 位作者 Lianjun Chen Yuan Li Zejing Liu Rongmin Zhang Pengjin Yang Pengcheng Li 《International Journal of Mining Science and Technology》 2026年第1期187-203,共17页
In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of roc... In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of rocks after stress relief introduces errors.To improve accuracy,this study proposes an in-situ stress solution theory that incorporates time-dependent stress relief effects.Triaxial stepwise loadingunloading rheological tests on granite and siltstone established quantitative relationships between instantaneous elastic recovery and viscoelastic recovery under different stress levels,confirming their impact on measurement accuracy.By integrating a dual-class elastic deformation recovery model,an improved in-situ stress solution theory was derived.Additionally,accounting for the nonlinear characteristics of rock masses,a determination method for time-dependent nonlinear mechanical parameters was proposed.Based on the CSIRO hollow inclusion strain cell,time-dependent strain correction equations and long-term confining pressure calibration equations were formulated.Finally,the proposed theory was successfully applied at one iron mine(736 m depth)in Xinjiang,China,and one coal mine(510 m depth)in Ningxia,China.Compared to classical theory,the calculated mean stress values showed accuracy improvements of 6.0%and 9.4%,respectively,validating the applicability and reliability of the proposed theory. 展开更多
关键词 In-situ stress solution theory Borehole overcoring technique Time-dependent effect of stress relief Viscoelastic recovery strain of rock In-situ stress measurement
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Effect and mechanism of Ti−O solid solution layer on interfacial bonding strength of cold roll bonded titanium/stainless steel laminated composite plate
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作者 Zhi-yan YANG Xue-feng LIU +1 位作者 Hong-ting CHEN Xin MA 《Transactions of Nonferrous Metals Society of China》 2026年第1期171-182,共12页
Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding str... Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding strength in titanium/stainless steel laminated composites were investigated.Results indicate that the hardened layer reduces the interfacial bonding strength from over 261 MPa to less than 204 MPa.During the cold roll-bonding process,the hardened layer fractures,leading to the formation of multi-scale cracks that are difficult for the stainless steel to fill.This not only hinders the development of an interlocking interface but also leads to the presence of numerous microcracks and hardened blocks along the nearly straight interface,consequently weakening the interfacial bonding strength.In metals with high work hardening rates,the conventional approach of enhancing interface interlocking and improving interfacial bonding strength by using a surface-hardened layer becomes less effective. 展开更多
关键词 titanium/stainless steel laminated composite plate Ti−O solid solution hardened layer interlocking interface formation mechanism interfacial bonding strength
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基于热弹-黏塑性本构的POM材料齿轮副啮合特性分析
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作者 刘明勇 韩新光 +2 位作者 欧阳周寰 胡俊 闫春爱 《工程科学与技术》 北大核心 2025年第2期159-170,共12页
为揭示负载、修形和温度对聚甲醛(POM-POM)齿轮副啮合特性的影响,建立热弹-黏塑性材料本构的POM-POM齿轮副3维有限元接触模型;结合POM材料的温度-模量效应,开展温度-应力顺序耦合的稳态热分析,并与POM-POM齿轮副温度服役测试结果对比;... 为揭示负载、修形和温度对聚甲醛(POM-POM)齿轮副啮合特性的影响,建立热弹-黏塑性材料本构的POM-POM齿轮副3维有限元接触模型;结合POM材料的温度-模量效应,开展温度-应力顺序耦合的稳态热分析,并与POM-POM齿轮副温度服役测试结果对比;在稳态热分析基础上,进行完全耦合瞬态热接触分析,并将瞬态温升与Blok温度结果对比;通过齿根应变试验,验证不同负载工况下齿根应变计算的有效性。结果表明:齿轮副的稳态温升呈现齿根高、齿顶与端面较低的分布规律,并随负载增大而上升;通过试验对比得到,有限元计算齿轮稳态温升与试验结果一致,且瞬态温升与Blok公式结果一致;POM-POM齿轮副仿真齿根应变位于试验测试应变误差带内,表明考虑温度-模量效应的热弹-黏塑性材料本构能够表征POM塑料齿轮的热学特性和力学特性。此外,POM-POM齿轮副传动过程中出现啮合线延长且偏离理论位置,且温度对啮合线影响较小。齿面修形可降低其啮合线长度,但不能改善其偏转程度;啮合角在啮入和啮出时会出现较大的变化,温度使其啮合角在双齿啮合区域上升约1℃。啮合刚度与负载相关,随着负载增加,啮合刚度下降且重合度上升。同等条件下,POM-POM齿轮副的传递误差幅值约是金属齿轮副的10倍,且温度使传递误差幅值上升约39%,齿面修形可降低24%左右的传递误差幅值。 展开更多
关键词 黏塑性 pom齿轮 啮合刚度 传递误差
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纤维长度对POM-ECC力学性能影响分析
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作者 周利剑 张睿 +2 位作者 胥立广 卢召红 邓华 《河南科学》 2025年第5期761-769,共9页
采用三种不同长度(8、12、16mm)的POM纤维制备ECC,通过三点弯曲试验和抗压强度试验探讨纤维长度对材料弯压性能的影响,并结合微观分析深入研究纤维的作用机理。最后,通过有限元软件ABAQUS建立有限元模型进行拓展研究。结果表明:随着纤... 采用三种不同长度(8、12、16mm)的POM纤维制备ECC,通过三点弯曲试验和抗压强度试验探讨纤维长度对材料弯压性能的影响,并结合微观分析深入研究纤维的作用机理。最后,通过有限元软件ABAQUS建立有限元模型进行拓展研究。结果表明:随着纤维长度的增加,纤维与基体的结合效果得到改善,ECC的应力分散能力显著提高,弯曲强度和抗压强度也呈递增趋势;较长的纤维有利于提升材料的韧性及残余强度,更适用于实际工程应用;同时,通过有限元模拟发现,纤维所分担应力随纤维长度的增大呈先增大后减小趋势,在24mm时达到最大应力。 展开更多
关键词 pom纤维 纤维长度 抗压强度 弯曲强度 韧性指数 有限元模拟
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纤维替代率对POM/PVA-ECC抗折性能的影响分析 被引量:1
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作者 胥立广 周利剑 +2 位作者 张睿 卢召红 邓华 《河南科学》 2025年第4期553-559,共7页
聚乙烯醇纤维增强水泥基复合材料(PVA-ECC)具有高韧性、高延性等优点,但其成本较高且性能局限,故限制了其在工程上的应用。为了降低成本并提升材料抗折能力,开发一种混杂POM/PVA纤维ECC(简称POM/PVA-ECC),并通过抗折试验及图像二值化方... 聚乙烯醇纤维增强水泥基复合材料(PVA-ECC)具有高韧性、高延性等优点,但其成本较高且性能局限,故限制了其在工程上的应用。为了降低成本并提升材料抗折能力,开发一种混杂POM/PVA纤维ECC(简称POM/PVA-ECC),并通过抗折试验及图像二值化方法探讨了不同POM纤维替代率对POM/PVA-ECC抗折强度、裂缝扩展情况、孔隙率的影响。结果表明:随着POM纤维替代率的增加,POM/PVA-ECC的抗折强度呈波动变化趋势、残余强度和孔隙率整体呈增加趋势,而裂缝扩展速率整体呈减小趋势。当POM纤维替代率为50%时,POM/PVA-ECC的抗折强度和残余强度均较好,且裂缝扩展速度最慢,故认为POM纤维替代率为50%时,POM/PVA-ECC的抗折性能最优。此外,研究发现裂缝宽度与残余强度之间存在较强的相关性,并基于此建立了裂缝宽度-残余抗折强度模型,该模型对于通过裂缝宽度预测残余强度,具有一定的实际应用价值。 展开更多
关键词 ECC pom纤维 PVA纤维 裂缝扩展 抗折强度
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Removal of hexavalent chromium in aquatic solutions by pomelo peel 被引量:7
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作者 Qiong Wang Cong Zhou +2 位作者 Yin-jie Kuang Zhao-hui Jiang Min Yang 《Water Science and Engineering》 EI CAS CSCD 2020年第1期65-73,共9页
This study investigated the removal of hexavalent chromium(Cr(VI)) in aqueous solutions using pomelo peel(PP) and FeCl3-modified pomelo peel(FPP) as novel biomass adsorbents.Batch adsorption experiments were performed... This study investigated the removal of hexavalent chromium(Cr(VI)) in aqueous solutions using pomelo peel(PP) and FeCl3-modified pomelo peel(FPP) as novel biomass adsorbents.Batch adsorption experiments were performed to evaluate the effects of pH,time,temperature,initial concentration,and adsorbent dose on Cr(VI) removal by PP and FPP.The results show that the maximum adsorption capacity of Cr(VI)was 21.55 mg/g for FPP and 0.57 mg/g for PP at a pH of 2.0 and a temperature of 40℃.The surface shape,microstructure,and chemical composition of FPP were analyzed with scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),and energy dispersive spectroscopy(EDS),and compared with those of PP.The results show that the adsorption performance of FPP was much better than that of PP,indicating that FPP can be an alternative high-efficiency adsorbent for Cr(VI) removal. 展开更多
关键词 Adsorption Hexavalent chromium REMOVAL Biomass ADSORBENT pomELO PEEL FeCl3-modified pomELO PEEL AQUATIC solution
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热粘弹-塑性本构的POM材料齿轮疲劳寿命分析
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作者 闫春爱 李皓 +1 位作者 韩新光 宋垚乐 《机械设计与制造》 北大核心 2025年第11期227-233,共7页
POM齿轮具有低噪音、耐磨损和自润滑性能等优点,其疲劳寿命问题被广泛关注。采用热粘弹-塑性本构模型描述POM材料特性,建立二维的POM-POM五齿有限元接触模型,并考虑齿轮补偿修形对啮合特性影响。基于BrownMiller-Morrow多轴疲劳寿命评... POM齿轮具有低噪音、耐磨损和自润滑性能等优点,其疲劳寿命问题被广泛关注。采用热粘弹-塑性本构模型描述POM材料特性,建立二维的POM-POM五齿有限元接触模型,并考虑齿轮补偿修形对啮合特性影响。基于BrownMiller-Morrow多轴疲劳寿命评价准则,对POM齿轮的接触疲劳寿命和弯曲疲劳寿命进行预测,对比分析修形方式、补偿修形参数和齿面摩擦系数对POM齿轮的接触疲劳和弯曲疲劳寿命影响。研究结果表明,相比于标准渐开线齿廓,补偿修形将齿轮啮合过程最大应力位于节线区域,且正应变幅值与剪应变幅值均小于标准齿轮的正应变幅值与剪应变幅值,可适当提升齿轮的接触疲劳寿命;通过对比典型去除材料修形、补偿修形和标准齿廓,齿廓修形均能提升齿轮疲劳寿命,其中补偿修形效果更显著。补偿修形指数对齿轮接触疲劳寿命更显著,但对弯曲疲劳寿命不显著。同时,随着补偿修形指数增大,齿轮啮合过程的最大正应变幅值、均值与最大剪应变幅值都逐渐减小,但补偿修形分段数的影响则相反。接触疲劳寿命与弯曲疲劳寿命会随着齿轮的摩擦系数增加而减小。 展开更多
关键词 pom齿轮 补偿修形 多轴疲劳 应力 应变
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Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy 被引量:2
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作者 Xin Zhou Dan Ma +7 位作者 Yi-Xiang He Jing Jin Hong-Lian Wang Yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen Zhi Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期110-125,共16页
BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.... BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.AIM To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus post-ESD.METHODS Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential ESD.Endoscopic examinations occurred on days 7 and 21 post-ESD.In vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was assessed.Profibrotic signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after ESD.After treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal layer.Additionally,the expression of fibrotic effector molecules was notably inhibited.Mechanistically,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/3.In vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen I.The 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated pEsF.CONCLUSION KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway. 展开更多
关键词 Kangfuxin solution Natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis
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POM-UHPC加固闽南地区石砌体窗间墙抗震性能数值分析
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作者 彭洋 李飞燕 吴应雄 《厦门大学学报(自然科学版)》 北大核心 2025年第6期1048-1056,共9页
[目的]针对高宽比大、截面尺寸小而极易在地震中率先破坏的窗间墙,前期提出采用掺入聚甲醛纤维的超高性能混凝土(POM-UHPC)对其进行点状嵌缝加固(即局部加固)并开展试验研究.本文进一步研究点状尺寸、点状平面面积和点状位置对石砌体窗... [目的]针对高宽比大、截面尺寸小而极易在地震中率先破坏的窗间墙,前期提出采用掺入聚甲醛纤维的超高性能混凝土(POM-UHPC)对其进行点状嵌缝加固(即局部加固)并开展试验研究.本文进一步研究点状尺寸、点状平面面积和点状位置对石砌体窗间墙抗震性能的影响.[方法]基于ABAQUS有限元软件,建立加固后石砌体窗间墙的有限元模型并通过试验结果验证模型的可靠性.对不同的点状尺寸、点状平面面积以及点状位置加固的模型进行数值分析.[结果]研究结果表明:在点状平面面积一定的情况下,点状尺寸和点状位置对窗间墙抗震性能基本没有影响;点状的平面面积增大,峰值荷载提升,但延性系数下降;点状之间的距离增大会延缓窗间墙屈服点以及峰值荷载点的出现.[结论]研究成果可为该新型抗震加固技术提供理论依据. 展开更多
关键词 石砌体窗间墙 点状嵌缝加固 pom-UHPC 数值分析
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Ascorbic acid-induced porous iodide layer for a high-purity two-step solution-processed tin-lead mixed perovskite photodetector 被引量:2
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作者 Liansong Liu Fengren Cao +3 位作者 Liukang Bian Meng Wang Haoxuan Sun Liang Li 《Journal of Materials Science & Technology》 2025年第7期227-232,共6页
Tin(Sn)-lead(Pb)mixed halide perovskites have attracted widespread interest due to their wider re-sponse wavelength and lower toxicity than lead halide perovskites,Among the preparation methods,the two-step method mor... Tin(Sn)-lead(Pb)mixed halide perovskites have attracted widespread interest due to their wider re-sponse wavelength and lower toxicity than lead halide perovskites,Among the preparation methods,the two-step method more easily controls the crystallization rate and is suitable for preparing large-area per-ovskite devices.However,the residual low-conductivity iodide layer in the two-step method can affect carrier transport and device stability,and the different crystallization rates of Sn-and Pb-based per-ovskites may result in poor film quality.Therefore,Sn-Pb mixed perovskites are mainly prepared by a one-step method.Herein,a MAPb_(0.5)Sn_(0.5)I_(3)-based self-powered photodetector without a hole transport layer is fabricated by a two-step method.By adjusting the concentration of the ascorbic acid(AA)addi-tive,the final perovskite film exhibited a pure phase without residues,and the optimal device exhibited a high responsivity(0.276 A W^(-1)),large specific detectivity(2.38×10^(12) Jones),and enhanced stability.This enhancement is mainly attributed to the inhibition of Sn2+oxidation,the control of crystal growth,and the sufficient reaction between organic ammonium salts and bottom halides due to the AA-induced pore structure. 展开更多
关键词 PEROVSKITE SN-PB PHOTODETECTOR Two-step solution method
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