In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ...In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.展开更多
Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery...Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery.We rst derive the projection formulas for a vector onto the feasible sets.The centralized circumcentered-reection method is designed to solve the convex feasibility problem.Some numerical experiments demonstrate the feasibility and e ectiveness of the proposed algorithm,showing superior performance compared to conventional alternating projection methods.展开更多
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t...Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates.展开更多
本文以辽河油田沈阳采油厂某采油作业区石油污染土壤为研究对象,探究H2O2浓度、FeSO4浓度、反应体系pH、水土比、反应时间等因素对石油污染土壤中石油烃降解效果的影响。研究结果表明,H2O2投加浓度对石油烃的降解效果影响显著,氧化剂和...本文以辽河油田沈阳采油厂某采油作业区石油污染土壤为研究对象,探究H2O2浓度、FeSO4浓度、反应体系pH、水土比、反应时间等因素对石油污染土壤中石油烃降解效果的影响。研究结果表明,H2O2投加浓度对石油烃的降解效果影响显著,氧化剂和催化剂浓度对Fenton反应过程中石油烃的氧化效果有较大影响,反应体系pH值为6.0时石油烃的去除效果最佳,合理的水土比能够提高氧化效率。不同程度污染土壤的修复效果表明,反应24 h后,Fenton反应基本完成,石油烃去除率分别为49.22%,55.31%和61.98%,该研究结果可为污染土壤环境修复提供科学依据。In this paper, the effects of H2O2 concentration, FeSO4 concentration, reaction system pH, water and soil ratio, and reaction time on the degradation of petroleum hydrocarbons in oil-polluted soil were studied in an oil production area of Shenyang oil production plant of Liaohe Oilfield. The research results show that the concentration of H2O2 has a significant impact on the degradation effect of petroleum hydrocarbons, and the concentration of oxidant and catalyst has a great impact on the oxidation effect of petroleum hydrocarbons in the Fenton reaction process. When the pH value of the reaction system is 6.0, the removal effect of petroleum hydrocarbons is the best, and reasonable water and soil ratio can improve the oxidation efficiency. The remediation effects of contaminated soil of different degrees show that after 24 h of reaction, Fenton reaction is basically completed, and the removal rates of petroleum hydrocarbons are 49.22%, 55.31% and 61.98%, respectively. The research results can provide scientific basis for the remediation of contaminated soil environment.展开更多
Abstract [ Objective] The degradation conditions and course of reactive brilliant red X-3B by Fenton oxidation was investigated to understand the feasibility of using Fenton oxidation for dye removal. [Metbed] By usin...Abstract [ Objective] The degradation conditions and course of reactive brilliant red X-3B by Fenton oxidation was investigated to understand the feasibility of using Fenton oxidation for dye removal. [Metbed] By using Fenton oxidation, the degradation conditions of reactive brilliant red X-3B wastewater was studied in different initial concentrations, then analyzed its degradation products and process through gas chromatography-mass spectrometer （GC-MS）. [ Remit] When H202：Fe2＋ （molar ratio） =3.1, the removal rate of CODc, was the highest. With the increase of Fe2＋ dos- age, the wastewater became red and more deposits generated. As CODc, of wastewater was 200,400 and 800 mg/L, the dosage of H202 was 0.5, 1.0 and 3.5 ml respectively, and the best initial pH of the wastewater was 4 -5, the removal rate of GODc, reached the maximum values. In addition, Fenton reaction was very fast, that is, most degradation occurred in the first 5 min. [ Cenclmion] Fenton oxidation technology is practical and efficient in the declradation of dves which are mineralized difficultly.展开更多
The aim of this work was to investigate the effect of different surfactants on the removal efficiency of heavy metals in sewage sludge treated by a method combining bio-acidification with Fenton oxidation. Four surfac...The aim of this work was to investigate the effect of different surfactants on the removal efficiency of heavy metals in sewage sludge treated by a method combining bio-acidification with Fenton oxidation. Four surfactants were adopted such as anionic surfactant(sodium dodecyl benzene sulfonate, SDBS), nonionic surfactants(tween-20 and tween-60) and cationic surfactant(hexadecyl trimethyl ammonium chloride, HTAC), respectively. The indigenous sulfur-oxidizing bacteria in bio-acidification phase were enriched and cultured from fresh activated sludge obtained from a wastewater treatment plant. It is shown that different surfactants exhibited distinct effect on the removal efficiency of heavy metals from sewage sludge. The nonionic surfactants,especially tween-60, promotes the solubilization of heavy metals, while the anionic and cationic surfactants hinder the removal of heavy metals. Copper is efficiently leached. The removal efficiency of cadium is relatively lower than that of Cu due to the demand for rigorous p H value. Lead is leached with a low efficiency as the formation of low soluble Pb SO4 precipitates.展开更多
基金Supported in part by Natural Science Foundation of Guangxi(2023GXNSFAA026246)in part by the Central Government's Guide to Local Science and Technology Development Fund(GuikeZY23055044)in part by the National Natural Science Foundation of China(62363003)。
文摘In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.
基金Supported by the Natural Science Foundation of Guangxi Province(Grant Nos.2023GXNSFAA026067,2024GXN SFAA010521)the National Natural Science Foundation of China(Nos.12361079,12201149,12261026).
文摘Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery.We rst derive the projection formulas for a vector onto the feasible sets.The centralized circumcentered-reection method is designed to solve the convex feasibility problem.Some numerical experiments demonstrate the feasibility and e ectiveness of the proposed algorithm,showing superior performance compared to conventional alternating projection methods.
基金Supported by the National Natural Science Foundation of China under Grant No.51975138the High-Tech Ship Scientific Research Project from the Ministry of Industry and Information Technology under Grant No.CJ05N20the National Defense Basic Research Project under Grant No.JCKY2023604C006.
文摘Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates.
文摘本文以辽河油田沈阳采油厂某采油作业区石油污染土壤为研究对象,探究H2O2浓度、FeSO4浓度、反应体系pH、水土比、反应时间等因素对石油污染土壤中石油烃降解效果的影响。研究结果表明,H2O2投加浓度对石油烃的降解效果影响显著,氧化剂和催化剂浓度对Fenton反应过程中石油烃的氧化效果有较大影响,反应体系pH值为6.0时石油烃的去除效果最佳,合理的水土比能够提高氧化效率。不同程度污染土壤的修复效果表明,反应24 h后,Fenton反应基本完成,石油烃去除率分别为49.22%,55.31%和61.98%,该研究结果可为污染土壤环境修复提供科学依据。In this paper, the effects of H2O2 concentration, FeSO4 concentration, reaction system pH, water and soil ratio, and reaction time on the degradation of petroleum hydrocarbons in oil-polluted soil were studied in an oil production area of Shenyang oil production plant of Liaohe Oilfield. The research results show that the concentration of H2O2 has a significant impact on the degradation effect of petroleum hydrocarbons, and the concentration of oxidant and catalyst has a great impact on the oxidation effect of petroleum hydrocarbons in the Fenton reaction process. When the pH value of the reaction system is 6.0, the removal effect of petroleum hydrocarbons is the best, and reasonable water and soil ratio can improve the oxidation efficiency. The remediation effects of contaminated soil of different degrees show that after 24 h of reaction, Fenton reaction is basically completed, and the removal rates of petroleum hydrocarbons are 49.22%, 55.31% and 61.98%, respectively. The research results can provide scientific basis for the remediation of contaminated soil environment.
基金Supported by Key Laboratory Project of Water Pollution Control of Guangdong Province,China (2010009)
文摘Abstract [ Objective] The degradation conditions and course of reactive brilliant red X-3B by Fenton oxidation was investigated to understand the feasibility of using Fenton oxidation for dye removal. [Metbed] By using Fenton oxidation, the degradation conditions of reactive brilliant red X-3B wastewater was studied in different initial concentrations, then analyzed its degradation products and process through gas chromatography-mass spectrometer （GC-MS）. [ Remit] When H202：Fe2＋ （molar ratio） =3.1, the removal rate of CODc, was the highest. With the increase of Fe2＋ dos- age, the wastewater became red and more deposits generated. As CODc, of wastewater was 200,400 and 800 mg/L, the dosage of H202 was 0.5, 1.0 and 3.5 ml respectively, and the best initial pH of the wastewater was 4 -5, the removal rate of GODc, reached the maximum values. In addition, Fenton reaction was very fast, that is, most degradation occurred in the first 5 min. [ Cenclmion] Fenton oxidation technology is practical and efficient in the declradation of dves which are mineralized difficultly.
基金Project(21276069)supported by the National Natural Science Foundation of ChinaProject(CX2012B139)supported by the Hunan Province Innovation Foundation for Postgraduate,China
文摘The aim of this work was to investigate the effect of different surfactants on the removal efficiency of heavy metals in sewage sludge treated by a method combining bio-acidification with Fenton oxidation. Four surfactants were adopted such as anionic surfactant(sodium dodecyl benzene sulfonate, SDBS), nonionic surfactants(tween-20 and tween-60) and cationic surfactant(hexadecyl trimethyl ammonium chloride, HTAC), respectively. The indigenous sulfur-oxidizing bacteria in bio-acidification phase were enriched and cultured from fresh activated sludge obtained from a wastewater treatment plant. It is shown that different surfactants exhibited distinct effect on the removal efficiency of heavy metals from sewage sludge. The nonionic surfactants,especially tween-60, promotes the solubilization of heavy metals, while the anionic and cationic surfactants hinder the removal of heavy metals. Copper is efficiently leached. The removal efficiency of cadium is relatively lower than that of Cu due to the demand for rigorous p H value. Lead is leached with a low efficiency as the formation of low soluble Pb SO4 precipitates.
