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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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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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Analytical solution for longitudinal responses of tunnels under combined effects of seismic waves and strike-slip faulting
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作者 Jie Tang Manchao He +2 位作者 Yafei Qiao Hanbing Bian Chun Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1266-1289,共24页
Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analyt... Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analytical solution to determine the longitudinal mechanical responses of tunnels subjected to the combined effects of seismic waves and strike-slip faulting.Adopting the elastic springbeam model,the seismic waves are modelled as shear horizontal(SH)waves and the fault dislocation follows an S-shaped pattern;the superposition principle for free-fielddisplacements caused by both effects is assumed.In addition,the transmission and reflectionof seismic waves at the fault-rock geological interface and the tangential contact conditions at the tunnel-rock interface are considered.The analytical model is validated against numerical simulations,confirmingits accuracy in calculating tunnel responses.Moreover,a parametric study is conducted to evaluate the impact of key factors,including fault displacement,fault zone width,fault dip angle,earthquake frequency,rock conditions,tunnel lining stiffness,and tangential contact conditions,on tunnel responses.Compared with each effect alone,the combined effects of seismic waves and strike-slip faulting significantlychange the tunnel deformation and internal forces,leading to increased tunnel responses,especially within the fault zone and near the fault-rock interfaces.Depending on specificparameters,tunnel responses can be classifiedinto seismic-dominated,faulting-dominated,and seismic-faulting coupled responses on the basis of the relative contributions of each effect.The proposed analytical solution can be applied to quickly predict the longitudinal mechanical behaviour of tunnels under such combined effects in engineering applications. 展开更多
关键词 Strike-slip faulting Longitudinal tunnel response Analytical solution Seismic waves Wave transmissions and reflections
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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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VUV/Fe^(2+)/Ox类芬顿体系对偶氮染料酸性红G的降解机理研究
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作者 王坤 陈伟 +5 位作者 唐玉朝 崔康平 伍昌年 朱先胜 孙海翔 黄显怀 《中国环境科学》 北大核心 2026年第2期785-796,共12页
构建了一种基于真空紫外(VUV)/Fe^(2+)/草酸(Ox)的新型无外源氧化剂类芬顿反应体系,并将其应用于偶氮染料酸性红G(ARG)的降解研究.结果表明,该体系可实现H_(2)O_(2)的动态释放,进而与Fe^(2+)形成类芬顿反应,且在较宽pH值范围内均能保持... 构建了一种基于真空紫外(VUV)/Fe^(2+)/草酸(Ox)的新型无外源氧化剂类芬顿反应体系,并将其应用于偶氮染料酸性红G(ARG)的降解研究.结果表明,该体系可实现H_(2)O_(2)的动态释放,进而与Fe^(2+)形成类芬顿反应,且在较宽pH值范围内均能保持高反应活性.结果表明:在ARG初始质量浓度为60mg/L、Fe^(2+)与Ox浓度分别为0.06和0.7mmol/L的条件下,VUV/Fe^(2+)/Ox体系对ARG的去除率在5min内即可达到96.2%,其降解过程符合准一级动力学模型.随着溶液初始pH值的升高,ARG去除率呈下降趋势,在pH=7时,一级速率常数k值仍可达0.454min⁻1,为pH=3时的69.6%,表明该体系在中性条件下仍能维持较高反应活性.反应初始5min内,体系中H_(2)O_(2)浓度逐渐上升至最高62.5µmol/L,随后缓慢下降,至9min时仍保持在51.8µmol/L.自由基捕获实验与EPR检测结果共同证实,羟基自由基(·OH)和超氧自由基(O_(2)^(·-))是该体系中的主要活性氧化物种.此外,水环境中常见的无机阴离子(HCO_(3)^(-)、NO_(3)^(-)、Cl^(-)、SO_(4)^(2-))均会对ARG降解产生不同程度的抑制作用.通过紫外可见吸收光谱及液相色谱-质谱联用(LC-MS)分析可知,降解过程中生成的活性氧(ROS)通过攻击ARG分子中的偶氮键和苯环结构,实现了染料的脱色与去除. 展开更多
关键词 VUV/Fe^(2+)/草酸体系 类芬顿反应 酸性红g 动态H_(2)O_(2)释放
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血清GPR18、PEDF与脓毒症相关急性呼吸窘迫综合征患者病情及临床转归的关系
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作者 张玥 杜新丽 +1 位作者 朱嵘 袁同洲 《国际检验医学杂志》 2026年第5期570-575,581,共7页
目的探讨血清G蛋白偶联受体18(GPR18)、色素上皮衍生因子(PEDF)与脓毒症相关急性呼吸窘迫综合征(S-ARDS)患者病情分度及临床转归的关系。方法前瞻性选取2023年1月至2025年2月该院收治的157例S-ARDS患者作为S-ARDS组,另选取同期80例健康... 目的探讨血清G蛋白偶联受体18(GPR18)、色素上皮衍生因子(PEDF)与脓毒症相关急性呼吸窘迫综合征(S-ARDS)患者病情分度及临床转归的关系。方法前瞻性选取2023年1月至2025年2月该院收治的157例S-ARDS患者作为S-ARDS组,另选取同期80例健康体检者作为对照组,采用酶联免疫吸附试验检测血清GPR18、PEDF水平。根据氧合指数将S-ARDS患者分为轻度S-ARDS组(47例)、中度S-ARDS组(57例)、重度S-ARDS组(53例),采用Spearman相关分析血清GPR18、PEDF水平与氧合指数的相关性。根据28d临床转归将S-ARDS患者分为死亡组和存活组。采用多因素Logistic回归分析S-ARDS患者临床转归不良的影响因素,受试者工作特征曲线和决策曲线分析血清GPR18、PEDF水平及二者联合对S-ARDS患者临床转归不良的预测效能及净效益,1000次Bootstrap自助抽样法计算一致性指数(C指数)进行内部验证。结果与对照组比较,S-ARDS组血清GPR18、PEDF水平降低(P<0.05)。轻度S-ARDS组、中度S-ARDS组、重度S-ARDS组血清GPR18、PEDF水平依次降低(P<0.05)。S-ARDS患者血清GPR18、PEDF水平与氧合指数呈正相关(rS=0.697、0.700,均P<0.001)。157例S-ARDS患者28d病死率为38.85%(61/157)。机械通气时间≥3d(OR=3.060,95%CI:1.069~8.763)、序贯器官衰竭评估评分增加(OR=1.470,95%CI:1.173~1.841)、急性生理学和慢性健康状况评价Ⅱ评分增加(OR=1.132,95%CI:1.046~1.225)为S-ARDS患者临床转归不良的独立危险因素,GPR18升高(OR=0.301,95%CI:0.158~0.571)、PEDF升高(OR=0.488,95%CI:0.346~0.687)为独立保护因素(P<0.05)。血清GPR18、PEDF水平及二者联合预测SARDS患者临床转归不良的曲线下面积分别为0.790、0.778、0.872,二者联合的曲线下面积最大(P<0.05);C指数为0.872;决策曲线分析显示,在阈值0.1~1.0内,二者联合的净效益大于血清GPR18、PEDF水平单独预测。结论S-ARDS患者血清GPR18、PEDF水平降低与病情加重及临床转归不良有关,二者联合对临床转归有较高的预测效能。 展开更多
关键词 脓毒症 急性呼吸窘迫综合征 g蛋白偶联受体18 色素上皮衍生因子 临床转归
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渗碳-激光冲击复合强化G20Cr2Ni4A磨损性能实验
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作者 何莉萍 张珺婷 +3 位作者 李宛桐 徐震昭 崔国栋 蔡振兵 《实验技术与管理》 北大核心 2026年第1期77-85,共9页
针对风电轴承钢易磨损、脱落等失效问题,该文对G20Cr2Ni4A低碳轴承钢基体进行渗碳和渗碳-激光强化复合处理后,结合磨损实验及微观组织形貌、硬度和成分表征结果,对比基体及表面处理后样品在不同磨损条件下的摩擦磨损特性,最后采用Abaqu... 针对风电轴承钢易磨损、脱落等失效问题,该文对G20Cr2Ni4A低碳轴承钢基体进行渗碳和渗碳-激光强化复合处理后,结合磨损实验及微观组织形貌、硬度和成分表征结果,对比基体及表面处理后样品在不同磨损条件下的摩擦磨损特性,最后采用Abaqus软件对磨损体积、应力等参数进行模拟仿真。结果表明:G20Cr2Ni4A基体组织由低碳板条状马氏体和少量铁素体组成;渗碳后表层组织主要为隐晶马氏体和粒状碳化物;渗碳-激光强化处理后表面主要是塑性变形层和氧化层,硬度较渗碳后表层提升26%,摩擦系数下降40%,磨损量减少26%。Abaqus模拟仿真结果与实验结果一致性较好,对理论分析材料的磨损性能起到了很好的辅助作用。该实验有助于学生将材料学科与计算机人工智能知识有机结合,在掌握材料磨损性能综合实验类项目的基础上,进一步提升创新思维和解决实际工程问题的能力。 展开更多
关键词 g20Cr2Ni4A 渗碳处理 激光冲击强化 磨损性能
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双重退火工艺对TC25G钛合金轧制棒材组织与性能的影响
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作者 陶海林 孙虎代 +3 位作者 蒋纪新 张伟 王少阳 冯秋元 《金属热处理》 北大核心 2026年第1期259-264,共6页
研究了双重退火工艺对TC25G钛合金轧制棒材显微组织和力学性能的影响。结果表明,随着一次退火温度的升高,合金初生α相含量降低,抗拉强度、屈服强度先降低后升高,冲击吸收能量先升高后降低。随着一次退火冷却速度的增加,组织发生了马氏... 研究了双重退火工艺对TC25G钛合金轧制棒材显微组织和力学性能的影响。结果表明,随着一次退火温度的升高,合金初生α相含量降低,抗拉强度、屈服强度先降低后升高,冲击吸收能量先升高后降低。随着一次退火冷却速度的增加,组织发生了马氏体转变,合金的强度升高、塑性及冲击性能下降。合金经过不同温度二次退火后的显微组织均为双态组织,随着二次退火温度的升高,初生α相尺寸及β转变组织中片层宽度略微增加,合金的强度先降低后升高,冲击吸收能量先升高后降低。TC25G钛合金棒材经940℃×1 h,空冷+570℃×4 h,空冷的双重退火处理后的综合力学性能较好。 展开更多
关键词 TC25g钛合金 双重退火 热处理 显微组织 力学性能
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基于改进G1法及高斯区间的水电机组健康评价模型 被引量:1
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作者 张彬桥 贺政全 +1 位作者 陈庆松 章泽生 《人民长江》 北大核心 2026年第1期178-187,共10页
针对现有水电机组健康状态评估中存在的模糊性和随机性问题,考虑到水电机组工况的多变性和复杂性,基于改进G1-CRITIC法和高斯区间隶属度提出了一种水电机组状态评价模型。首先,根据水电机组的结构特征和运行规律,建立了健康状态综合评... 针对现有水电机组健康状态评估中存在的模糊性和随机性问题,考虑到水电机组工况的多变性和复杂性,基于改进G1-CRITIC法和高斯区间隶属度提出了一种水电机组状态评价模型。首先,根据水电机组的结构特征和运行规律,建立了健康状态综合评价指标体系。结合改进的G1-CRITIC法构建了组合权重计算模型,综合考虑指标之间的相关性以及专家的理性判断,对主观和客观权重的组合进行优化;利用高斯阈值方法对设备检修效果评价指标进行量化,计算指标的劣化度;将水电机组健康状态量化指标的劣化度应用于改进的模糊隶属度模型中,求解各指标的模糊评价矩阵,推导出目标水电机组的模糊状态评价矩阵,给出检修前后的隶属度函数和综合得分。实际水电站中不同工况下的应用实例,验证了该方法在不同工况下对水电机组健康状态的准确评估能力。 展开更多
关键词 水电机组健康状态 改进g1-CRITIC法 指标劣化度 高斯区间隶属度 改进模糊隶属度模型
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一株猪流行性腹泻病毒G2b亚型细胞适应性毒株的复制特性及致病性
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作者 杨帆 胡国芳 +5 位作者 魏子文 周莹珊 宋厚辉 何海健 董婉玉 王晓杜 《畜牧兽医学报》 北大核心 2026年第2期955-964,共10页
旨在探究猪流行性腹泻病毒(PEDV)流行株细胞适应后的复制特性及致病性,本研究将分离自某规模化猪场的PEDV流行毒株在Vero细胞中连续传代至不同代次,分别评价该毒株在细胞上的生物学特性,并将第25代和第141代病毒接种至3日龄仔猪,以比较... 旨在探究猪流行性腹泻病毒(PEDV)流行株细胞适应后的复制特性及致病性,本研究将分离自某规模化猪场的PEDV流行毒株在Vero细胞中连续传代至不同代次,分别评价该毒株在细胞上的生物学特性,并将第25代和第141代病毒接种至3日龄仔猪,以比较其致病性差异。结果表明:临床病料接种液盲传至第4代时,在Vero细胞上形成PEDV典型合胞体病变;传代至25代时,细胞病变形态与病毒滴度趋于稳定;传代至141代时,病毒滴度显著提高,并诱发更快速的细胞病变效应。间接免疫荧光试验(IFA)可特异性检出PEDV N蛋白表达,序列分析表明该毒株为G2b型。仔猪攻毒试验表明,与亲本低代次毒株(YJH/2017/F25)相比,YJH/2017/F141接种组未出现明显临床症状或组织病理损伤,且肛拭子病毒排放量显著减少,各项指标与DMEM对照组无显著差异,该毒株的致病性较低而具有较好安全性。以上结果说明该流行毒株在体外连续传代后获得了更好的细胞适应性且对新生仔猪的致病性降低,本研究为PEDV弱毒疫苗研发提供新的候选毒株,其全基因组序列和生物学特征也为后续重组病毒研究奠定了基础。 展开更多
关键词 猪流行性腹泻病毒 g2b型 细胞适应毒株 生物学特性
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6G绿色内生网络技术研究
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作者 吕婷 李福昌 +1 位作者 张忠皓 曹亘 《邮电设计技术》 2026年第2期11-16,共6页
作为新一代信息服务网络,6G网络在性能跃升的同时面临能耗上升的严峻挑战。为了促进6G可持续发展,分析了6G绿色内生网络的驱动力与挑战,从绿色组网架构、通感算智协同调度、端网协同的绿色空口、基于AI的智能节能几个方面介绍了6G绿色... 作为新一代信息服务网络,6G网络在性能跃升的同时面临能耗上升的严峻挑战。为了促进6G可持续发展,分析了6G绿色内生网络的驱动力与挑战,从绿色组网架构、通感算智协同调度、端网协同的绿色空口、基于AI的智能节能几个方面介绍了6G绿色内生网络技术,涉及6G网络设计、部署、运行、编排管理等各环节,系统性构建6G节能技术体系。 展开更多
关键词 6g 绿色内生 绿色组网 绿色空口 智能节能
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基于5G承载网硬切片部署方案研究及测试验证
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作者 张旭 屠礼彪 +1 位作者 郭胜楠 任枫华 《邮电设计技术》 2026年第1期24-28,共5页
为满足5G业务的差异化服务需求,推进5G承载网网络差异化能力构建,提出基于5G承载网的网络切片部署方案,并通过模拟测试论证了方案可行性,实现了异厂家技术解耦。该方案在实现业务差异化承载的同时,满足用户的定制化需求,推动网络高质量... 为满足5G业务的差异化服务需求,推进5G承载网网络差异化能力构建,提出基于5G承载网的网络切片部署方案,并通过模拟测试论证了方案可行性,实现了异厂家技术解耦。该方案在实现业务差异化承载的同时,满足用户的定制化需求,推动网络高质量发展和业务综合承载。 展开更多
关键词 5g 硬切片 FlexE 差异化服务
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浙江省5G+智慧医疗急救平台应用的伦理风险与治理路径
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作者 陈勰 钟誉豪 +5 位作者 赵灿灿 沈佳 许文萱 朱海晨 蒋春艳 李章平 《温州医科大学学报》 2026年第1期79-84,共6页
目的:研究5G+智慧医疗急救平台应用的伦理风险和治理路径,促进智慧急救高质量健康发展。方法:2024年11月选取浙江杭州、衢州、温州221名急救人员,采用自编问卷调查分析5G+智慧医疗急救的平台载体与使用频次、平台衔接与硬件兼容、数据... 目的:研究5G+智慧医疗急救平台应用的伦理风险和治理路径,促进智慧急救高质量健康发展。方法:2024年11月选取浙江杭州、衢州、温州221名急救人员,采用自编问卷调查分析5G+智慧医疗急救的平台载体与使用频次、平台衔接与硬件兼容、数据共享与隐私保护、责任划分与归属界定等情况。结果:浙江省智慧急救建设走在全国前列,5G移动复苏单元、送血无人机、空中医疗救援体系等开创性做法让患者呼救更便捷、救护车到达更快速、院前院内救治衔接更紧密。浙江省5G+智慧医疗急救平台存在多平台分立问题导致平台衔接与区域协同救治的数字壁垒,面临黑客攻击、恶意软件或内部数据泄露等安全威胁,责任认定具有模糊性,容易发生争议性风险。结论:5G+智慧医疗急救平台的伦理风险包括公平可及风险、数据安全风险、责任归属风险。为此,亟待各级政府协同医院、第三方机构全力构建数字信息中控台,打通公安、交通等多部门数据,形成统一接入、智能的硬件生态体系。要构建院间标准体系与硬件标准规范,设置专项支持基金。构建数据透明化与安全防护双机制,明确急救数据收集、存储、使用各环节责任主体,实现责任主体明确化与全流程追溯。 展开更多
关键词 5g技术 智慧医疗急救平台 伦理风险 治理路径
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