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复合Poisson-Geometric风险下带投资和混合保费收取的生存概率
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作者 覃利华 黄鸿君 《贵州师范大学学报(自然科学版)》 北大核心 2025年第5期115-121,共7页
研究一类保费混合收取且带有投资复合Poisson-Geometric风险模型的生存概率。利用全期望公式、伊藤积分公式和积分-微分方程等工具,首先推导了生存概率满足的积分-微分方程,其次当保费额和索赔额均服从特定指数分布条件下得到生存概率... 研究一类保费混合收取且带有投资复合Poisson-Geometric风险模型的生存概率。利用全期望公式、伊藤积分公式和积分-微分方程等工具,首先推导了生存概率满足的积分-微分方程,其次当保费额和索赔额均服从特定指数分布条件下得到生存概率的微分方程及解析解,最后进行数值实验模拟分析偏离系数、单位投资收益率、线性保费收入、初始资本、索赔强度等关键参数对生存概率的影响。数值实验结果表明:保险公司的生存概率是单位投资收益率、线性保费收入的增函数,是偏离系数、索赔额的减函数,进而验证了结果的合理性。 展开更多
关键词 复合poisson-geometric过程 生存概率 风险投资 保费混合收取
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带线性红利和干扰的复合Poisson-Geometric风险模型的破产问题
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作者 侯致武 乔克林 高磊 《贵州大学学报(自然科学版)》 2024年第6期8-13,共6页
考虑了常利力环境下,包含线性红利、随机干扰和随机保费的复合P-G风险模型。通过应用全期望公式,推导出该模型的Gerber-Shiu函数及破产概率的更新方程。在不考虑分红且保费额和索赔额均服从指数分布时,进一步得到了破产概率所满足的具... 考虑了常利力环境下,包含线性红利、随机干扰和随机保费的复合P-G风险模型。通过应用全期望公式,推导出该模型的Gerber-Shiu函数及破产概率的更新方程。在不考虑分红且保费额和索赔额均服从指数分布时,进一步得到了破产概率所满足的具体微分方程,并求解得到了其解析表达式。通过数值实验,系统分析了多个关键因素对破产概率的具体影响,所得结论与保险公司的实际经营情况相吻合。 展开更多
关键词 复合poisson-geometric过程 线性红利 GERBER-SHIU函数 破产概率
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稀疏二维Poisson-Geometric风险模型的生存概率
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作者 谢康 廖基定 刘耿华 《南华大学学报(自然科学版)》 2024年第5期85-89,共5页
本文研究了二维Poisson-Geometric风险模型,理赔过程为稀疏相依的。利用概率论中的全概率方法,得出了满足于此二维风险模型生存概率的偏积分微分方程。利用这个二维风险模型的强马尔科夫性,得到了一个使得该模型生存函数导数连续的充分... 本文研究了二维Poisson-Geometric风险模型,理赔过程为稀疏相依的。利用概率论中的全概率方法,得出了满足于此二维风险模型生存概率的偏积分微分方程。利用这个二维风险模型的强马尔科夫性,得到了一个使得该模型生存函数导数连续的充分条件。 展开更多
关键词 二维风险模型 poisson-geometric计数过程 生存概率
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Dendritic spine degeneration:a primary mechanism in the aging process 被引量:1
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作者 Gonzalo Flores Leonardo Aguilar-Hernández +3 位作者 Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán 《Neural Regeneration Research》 SCIE CAS 2025年第6期1696-1698,共3页
Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a w... Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023). 展开更多
关键词 AGING process STRESS
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Prediction and optimization of flue pressure in sintering process based on SHAP 被引量:2
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作者 Mingyu Wang Jue Tang +2 位作者 Mansheng Chu Quan Shi Zhen Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期346-359,共14页
Sinter is the core raw material for blast furnaces.Flue pressure,which is an important state parameter,affects sinter quality.In this paper,flue pressure prediction and optimization were studied based on the shapley a... Sinter is the core raw material for blast furnaces.Flue pressure,which is an important state parameter,affects sinter quality.In this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment measures.First,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction model.The effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment conditions.The operating parameter combination was then pushed.The flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect. 展开更多
关键词 sintering process flue pressure shapley additive explanation PREDICTION OPTIMIZATION
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带有投资收益率和双保费复合Poisson-Geometric风险模型的研究
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作者 覃利华 黄鸿君 洪小萍 《兰州文理学院学报(自然科学版)》 2024年第4期13-19,共7页
研究了保费收入为线性增长和随机保费的风险模型,且随机保费的保单数服从复合Poisson过程,理赔次数服从复合Poisson-Geometric过程.应用全概率公式和积分变换公式,推导了该模型Gerber-Shiu折现罚金函数满足的更新方程,并当随机保费、理... 研究了保费收入为线性增长和随机保费的风险模型,且随机保费的保单数服从复合Poisson过程,理赔次数服从复合Poisson-Geometric过程.应用全概率公式和积分变换公式,推导了该模型Gerber-Shiu折现罚金函数满足的更新方程,并当随机保费、理赔过程均服从特定指数分布时,得到了该模型破产概率的解析解,最后通过数值模拟对理论进行了分析验证. 展开更多
关键词 复合poisson-geometric过程 破产概率 更新方程 混合保费
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Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process 被引量:1
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作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 EI 2025年第1期331-347,共17页
Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the p... Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the performanceof PV modules gradually declines due to internal degradation and external environmental factors.This cumulativedegradation impacts the overall reliability of photovoltaic power generation. This study addresses the complexdegradation process of PV modules by developing a two-stage Wiener process model. This approach accountsfor the distinct phases of degradation resulting from module aging and environmental influences. A powerdegradation model based on the two-stage Wiener process is constructed to describe individual differences inmodule degradation processes. To estimate the model parameters, a combination of the Expectation-Maximization(EM) algorithm and the Bayesian method is employed. Furthermore, the Schwarz Information Criterion (SIC) isutilized to identify critical change points in PV module degradation trajectories. To validate the universality andeffectiveness of the proposed method, a comparative analysis is conducted against other established life predictiontechniques for PV modules. 展开更多
关键词 Photovoltaic modules DEGRADATION stochastic processes lifetime prediction
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An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells 被引量:1
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作者 Shuai Xu Youdi Zhang +6 位作者 Yanna Sun Pei Cheng Zhaoyang Yao Ning Li Long Ye Lijian Zuo Ke Gao 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期372-375,共4页
Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network act... Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer deposition.This optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture capability.This approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs. 展开更多
关键词 Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management
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带投资和分红策略下复合Poisson-Geometric风险模型的研究
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作者 覃利华 李越洋 《井冈山大学学报(自然科学版)》 2024年第5期9-16,共8页
考虑投资和分红策略下,建立带有混合收费及索赔计数服从复合Poisson-Geometric过程的风险模型。运用全期望公式与积分变换公式,研究该模型红利付款现值期望函数满足的微积分方程和特定指数分布下满足的微分方程及解析解,通过数值模拟分... 考虑投资和分红策略下,建立带有混合收费及索赔计数服从复合Poisson-Geometric过程的风险模型。运用全期望公式与积分变换公式,研究该模型红利付款现值期望函数满足的微积分方程和特定指数分布下满足的微分方程及解析解,通过数值模拟分析了固定保费率、初始资本、投资资产、索赔强度和红利边界对红利付款现值期望函数的影响,并分析其经济意义。 展开更多
关键词 复合poisson-geometric过程 红利付款现值期望函数 分红策略 投资策略 积分微分方程
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The profound review of Fenton process:What’s the next step? 被引量:5
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作者 Yimin Lin Junlian Qiao +1 位作者 Yuankui Sun Hongyu Dong 《Journal of Environmental Sciences》 2025年第1期114-130,共17页
Fenton and Fenton-like processes,which could produce highly reactive species to degrade organic contaminants,have been widely used in the field of wastewater treatment.Therein,the chemistry of Fenton process including... Fenton and Fenton-like processes,which could produce highly reactive species to degrade organic contaminants,have been widely used in the field of wastewater treatment.Therein,the chemistry of Fenton process including the nature of active oxidants,the complicated reactions involved,and the behind reason for its strongly pH-dependent performance,is the basis for the application of Fenton and Fenton-like processes in wastewater treatment.Nevertheless,the conflicting views still exist about the mechanism of the Fenton process.For instance,reaching a unanimous consensus on the nature of active oxidants(hydroxyl radical or tetravalent iron)in this process remains challenging.This review comprehensively examined the mechanism of the Fenton process including the debate on the nature of active oxidants,reactions involved in the Fenton process,and the behind reason for the pH-dependent degradation of contaminants in the Fenton process.Then,we summarized several strategies that promote the Fe(Ⅱ)/Fe(Ⅲ)cycle,reduce the competitive consumption of active oxidants by side reactions,and replace the Fenton reagent,thus improving the performance of the Fenton process.Furthermore,advances for the future were proposed including the demand for the high-accuracy identification of active oxidants and taking advantages of the characteristic of target contaminants during the degradation of contaminants by the Fenton process. 展开更多
关键词 Advanced oxidation process FENTON Hydroxyl radical Fe(IV) Wastewater treatment
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The rupture process of the Hualien M 7.3 sequence on April 3,2024 被引量:1
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作者 Zhigao Yang Huifang Chen 《Earthquake Research Advances》 2025年第1期30-37,共8页
The Hualien M 7.3 earthquake on April 3,2024,was a significant and strong earthquake in Taiwan,China in the past two decades.The rupture process of the main shock and strong aftershocks is of great significance to the... The Hualien M 7.3 earthquake on April 3,2024,was a significant and strong earthquake in Taiwan,China in the past two decades.The rupture process of the main shock and strong aftershocks is of great significance to the subsequent seismic activity and seismogenic tectonic research.Based on local strong-motion data,we used the IDS(Iterative Deconvolution and Stacking)method to obtain the rupture process of the mainshock and two strong aftershocks on the 23rd.The rupture of the mainshock was mainly unilateral,lasting 31 s,with a maximum slip of 2m,and the depth of the large slip zone is about 41–49 km.There is a clear difference between the rupture depth of the main shock and the two strong aftershocks.The depths of the large slip zones of the latter two are 3–9 km and 8–10 km,respectively.There is also a significant difference in the seismogenic fault between the mainshock and the aftershocks,and we believe that there are two seismogenic fault zones in the study area,the deep and the shallow fault zone.The slip of the deep faults activates the shallow faults. 展开更多
关键词 Hualien earthquake Rupture process IDS method Focal mechanism
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Enhanced magnetic properties in a Fe-based amorphous alloy via ultrasonic vibration rapid processing 被引量:1
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作者 Hong-Zhen Li Sajad Sohrabi +4 位作者 Xin Li Lu-Yao Li Jiang Ma Huan-Lin Peng Chao Yang 《Rare Metals》 2025年第4期2853-2860,共8页
In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment techni... In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment technique known as ultrasonic vibration rapid processing(UVRP),which enables the formation of high-density strong magnetic α-Fe clusters,thereby enhancing the soft magnetic properties of Fe_(78)Si(13)B_(9) amorphous alloy ribbon. 展开更多
关键词 enhancing soft magnetic properties soft magnetic properties physical propertieshereinwe Fe based amorphous alloy amorphous alloy ribbon ultrasonic vibration rapid processing uvrp which Fe clusters ultrasonic vibration rapid processing
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Buoyancy characteristic analysis and optimization of precast concrete slab track during casting process of self-compacting concrete 被引量:1
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作者 Pengsong Wang Tao Xin +2 位作者 Peng Chen Sen Wang Di Cheng 《Railway Sciences》 2025年第2期159-173,共15页
Purpose–The precast concrete slab track(PST)has advantages of fewer maintenance frequencies,better smooth rides and structural stability,which has been widely applied in urban rail transit.Precise positioning of prec... Purpose–The precast concrete slab track(PST)has advantages of fewer maintenance frequencies,better smooth rides and structural stability,which has been widely applied in urban rail transit.Precise positioning of precast concrete slab(PCS)is vital for keeping the initial track regularity.However,the cast-in-place process of the self-compacting concrete(SCC)filling layer generally causes a large deformation of PCS due to the water-hammer effect of flowing SCC,even cracking of PCS.Currently,the buoyancy characteristic and influencing factors of PCS during the SCC casting process have not been thoroughly studied in urban rail transit.Design/methodology/approach–In this work,a Computational Fluid Dynamics(CFD)model is established to calculate the buoyancy of PCS caused by the flowing SCC.The main influencing factors,including the inlet speed and flowability of SCC,have been analyzed and discussed.A new structural optimization scheme has been proposed for PST to reduce the buoyancy caused by the flowing SCC.Findings–The simulation and field test results showed that the buoyancy and deformation of PCS decreased obviously after adopting the new scheme.Originality/value–The findings of this study can provide guidance for the control of the deformation of PCS during the SCC construction process. 展开更多
关键词 Casting process Buoyancy characteristics Precast concrete slab track SIMULATION Field test OPTIMIZATION
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Adsorption-Driven Interfacial Interactions: The Key to Enhanced Performance in Heterogeneous Advanced Oxidation Processes 被引量:1
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作者 Jinming Luo Deyou Yu +3 位作者 Kaixing Fu Zhuoya Fang Xiaolin Zhang Mingyang Xing 《Engineering》 2025年第4期22-25,共4页
Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the el... Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies. 展开更多
关键词 Heterogeneous advanced oxidation processES ADSORPTION Pollutant degradation Dual active sites CATALYSIS SELECTIVITY
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Foundation Models for the Process Industry:Challenges and Opportunities 被引量:1
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作者 Lei Ren Haiteng Wang +3 位作者 Yuqing Wang Keke Huang Lihui Wang Bohu Li 《Engineering》 2025年第9期53-59,共7页
With the emergence of general foundational models,such as Chat Generative Pre-trained Transformer(ChatGPT),researchers have shown considerable interest in the potential applications of foundation models in the process... With the emergence of general foundational models,such as Chat Generative Pre-trained Transformer(ChatGPT),researchers have shown considerable interest in the potential applications of foundation models in the process industry.This paper provides a comprehensive overview of the challenges and opportunities presented by the use of foundation models in the process industry,including the frameworks,core applications,and future prospects.First,this paper proposes a framework for foundation models for the process industry.Second,it summarizes the key capabilities of industrial foundation models and their practical applications.Finally,it highlights future research directions and identifies unresolved open issues related to the use of foundation models in the process industry. 展开更多
关键词 Industrial foundation model process manufacturing Artificial intelligence-generated content Embodied intelligence Intelligent manufacturing
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Relative vacuum reduction innovative processes applied in primary magnesium production-Comprehensive analysis of thermodynamics,resource,energy flow,and carbon emission 被引量:1
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作者 Xiaolong Li Tingan Zhang +3 位作者 Yan Liu Junhua Guo Jingzhong Xu Yuanyuan Liang 《Journal of Magnesium and Alloys》 2025年第7期3134-3149,共16页
Magnesium and magnesium alloys,serving as crucial lightweight structural materials and hydrogen storage elements,find extensive applications in space technology,aviation,automotive,and magnesium-based hydrogen industr... Magnesium and magnesium alloys,serving as crucial lightweight structural materials and hydrogen storage elements,find extensive applications in space technology,aviation,automotive,and magnesium-based hydrogen industries.The global production of primary magnesium has reached approximately 1.2 million tons per year,with anticipated diversification in future applications and significant market demand.Nevertheless,approximately 80%of the world’s primary magnesium is still manufactured through the Pidgeon process,grappling with formidable issues including high energy consumption,massive carbon emission,significant resource depletion,and environmental pollution.The implementation of the relative vacuum method shows potential in breaking through technological challenges in the Pidgeon process,facilitating clean,low-carbon continuous magnesium smelting.This paper begins by introducing the principles of the relative vacuum method.Subsequently,it elucidates various innovative process routes,including relative vacuum ferrosilicon reduction,aluminum thermal reduction co-production of spinel,and aluminum thermal reduction co-production of calcium aluminate.Finally,and thermodynamic foundations of the relative vacuum,a quantitative analysis of the material,energy flows,carbon emission,and production cost for several new processes is conducted,comparing and analyzing them against the Pidgeon process.The study findings reveal that,with identical raw materials,the relative vacuum silicon thermal reduction process significantly decreases raw material consumption,energy consumption,and carbon dioxide emissions by 15.86%,30.89%,and 26.27%,respectively,compared to the Pidgeon process.The relative vacuum process,using magnesite as the raw material and aluminum as the reducing agent,has the lowest magnesium-to-feed ratio,at only 3.385.Additionally,its energy consumption and carbon dioxide emissions are the lowest,at 1.817 tce/t Mg and 7.782 t CO_(2)/t Mg,respectively.The energy consumption and carbon emissions of the relative vacuum magnesium smelting process co-producing calcium aluminate(12CaO·7Al_(2)O_(3),3CaO·Al_(2)O_(3),and CaO·Al_(2)O_(3))are highly correlated with the consumption of dolomite in the raw materials.When the reduction temperature is around 1473.15 K,the critical volume fraction of magnesium vapor for different processes varies within the range of 5%–40%.Production cost analysis shows that the relative vacuum primary magnesium smelting process has significant economic benefits.This paper offers essential data support and theoretical guidance for achieving energy efficiency,carbon reduction in magnesium smelting,and the industrial adoption of innovative processes. 展开更多
关键词 Magnesium smelting Relative vacuum reduction process THERMODYNAMICS Resource and energy flow Carbon emission
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A new multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth 被引量:1
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作者 Xinghui HAN Yanhui WANG +3 位作者 Lin HUA Wuhao ZHUANG Fangyan ZHENG Wei FENG 《Chinese Journal of Aeronautics》 2025年第1期568-585,共18页
Spiral bevel gears are critical transmission components,and are widely used in the aerospace field.This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears.Firstly,the multi-DOF ... Spiral bevel gears are critical transmission components,and are widely used in the aerospace field.This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears.Firstly,the multi-DOF envelope forming principle of spiral bevel gears is proposed.Secondly,the design methods for the envelope tool geometry and movement are proposed based on the envelope geometry and movement relationships.Thirdly,the metal flow and tooth filling laws are revealed through 3D FE simulation of the multi-DOF envelope forming process of a typical spiral bevel gear.Fourthly,a new method for separating the envelope tool and the formed spiral bevel gear with back taper tooth is proposed to avoid their interference.Finally,experiments on multi-DOF envelope forming of this typical spiral bevel gear are conducted using new heavy load multi-DOF envelope forming equipment.The simulation and experimental results show the feasibility of the proposed multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth and the corresponding process design methods. 展开更多
关键词 Multi-DOF envelope forming Spiral bevel gear Back taper tooth Metal flow process design
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Towards a blank design method for manufacturing big-tapered profiled ring disk by spinning-rolling process 被引量:1
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作者 Xuechao LI Lianggang GUO +1 位作者 Xiaoqing CHEN Heng LI 《Chinese Journal of Aeronautics》 2025年第1期70-86,共17页
The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficien... The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficiency and low-cost manufacturing of the component.Blank design is the key part of plastic forming process design.For spinning-rolling process,the shape and size of the blank play a crucial role in process stability,deformation behavior and dimensional accuracy.So this work proposes a blank design method to determine the geometry structure and sizes of the blank.The mathematical model for calculating the blank size has been deduced based on volume conservation and neutral layer length invariance principle.The FE simulation and corresponding trial production of an actual big-tapered profiled ring disk show that the proposed blank design method is applicative.In order to obtain a preferred blank,the influence rules of blank size determined by different deformation degrees(rolling ratio k)on the spinning-rolling process are revealed by comprehensive FE simulations.Overall considering the process stability,circularity of the deformed ring disk and forming forces,a reasonable range of deformation degree(rolling ratio k)is recommended for the blank design of the new spinning-rolling process. 展开更多
关键词 Blank design method Spinning-rolling process Big-tapered profiled ring disk Rolling ratio Intelligent FE simulation
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Optimization of Surface Layer Properties of Mg-9Li-1Zn Alloy by Ultrasonic Surface Rolling Process and its Impact on Corrosion Behavior 被引量:1
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作者 Huimin Yang Kun Yang +1 位作者 Guobing Wei Rongguang Li 《Acta Metallurgica Sinica(English Letters)》 2025年第8期1421-1435,共15页
The Mg-9Li-1Zn(LZ91)alloy was subjected to an ultrasonic surface rolling process(USRP)with varying passes for the purpose of modifying its surface state.The USRP transformed surface residual stress from initial tensil... The Mg-9Li-1Zn(LZ91)alloy was subjected to an ultrasonic surface rolling process(USRP)with varying passes for the purpose of modifying its surface state.The USRP transformed surface residual stress from initial tensile stress to compressive stress,decreasing the surface roughness and increasing the ratio of the β-Li phase.The USRPed LZ91 sample(3 passes)showed superior corrosion resistance,with the corrosion current density changing from 57.11 to 24.70μA cm^(-2),and the polarization resistance increasing from 576.3 to 1146.1Ωcm^(2).According to the corrosion procedure evaluations,in situ observation revealed that the LZ91 alloy initially experiences pitting,which subsequently develops into cracking.The substantial area coverage of the β-Li phase facilitates the formation of a protective film on the surface,effectively delaying localized corrosion. 展开更多
关键词 Dual-phase Mg-Li alloy Ultrasonic surface rolling process Oxide film Local corrosion Compressive residual stress
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A Novel Synthetic Process of Daprodustat
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作者 Xu Zhiyong Lin Xiaohui +3 位作者 Zhu Yuanyuan Zhang Shuangshuang Long Jiao Gu Shuangxi 《有机化学》 北大核心 2025年第9期3335-3342,共8页
An efficient and practical synthetic process for Daprodustat was developed.Starting with N,N'-dicyclohexylcarbodiimide(DCC)and malonic acid,the key intermediate 1,3-dicyclohexylpyrimidine-2,4,6(1H,3H,5H)-trione wa... An efficient and practical synthetic process for Daprodustat was developed.Starting with N,N'-dicyclohexylcarbodiimide(DCC)and malonic acid,the key intermediate 1,3-dicyclohexylpyrimidine-2,4,6(1H,3H,5H)-trione was synthesized via condensation reaction with 91%yield.Subsequent activation of this intermediate by 1,1'-carbonyldiimidazole(CDI),followed by a one-pot reaction with glycine ethyl ester hydrochloride,directly afforded Daprodustat in 92%yield with>99.8%HPLC purity.The process achieved an overall yield of 84%upon validation at 62-gram scale.Structural confirmation of the key intermediate was accomplished through nuclear magnetic resonance(NMR)spectroscopy and high-resolution mass spectrometry(HRMS).Compared with existing methods,this streamlined protocol demonstrates advantages including simplified operation,reduced reaction time,and lower production costs,offering significant potential for industrial-scale synthesis of Daprodustat. 展开更多
关键词 Daprodustat synthetic process one-pot method
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