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Journal of Iron and Steel Research(International) 2024年第3期31卷 608-621页

作者： Zhe wang Qi-long Wei cheng-bin Shi Zhan-cheng guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was investigated.The results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and Al-O-Si.Furthermore,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of slag.The increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the slag.The slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure

Recent Advances in Boron-Containing Acenes:Synthesis,Properties,and Optoelectronic Applications

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Chinese Journal of Chemistry 2023年第11期41卷 1355-1373页

作者： Yongkang guo cheng Chen Xiao-Ye wang State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin300071 China

Acenes with linearly fused benzene rings have attracted much attention due to their intriguing optical and electronic properties.Nevertheless,the poor ambient stability of longer acenes has hampered the investigation of their physicochemical properties and potential applications.The incorporation of main group elements into the acene backbones provides a viable strategy to enhance the stability,and meanwhile,generates a new family of heteroatom-doped acenes(namely heteroacenes)with modified properties and functions.In particular,boron-containing acenes represent an attractive class of heteroacenes owing to the existence of vacant p orbital of boron,which endows theπ-conjugated systems with appealing features,such as Lewis acidity,electron-accepting capability,stimuli-responsivity,and adjustable photophysical properties.During the past decade,significant progress has been achieved in the synthesis and applications of boron-containing acenes,but a focused review on this topic has been elusive.Here,we summarize the recent advances in the studies on boron-containing acenes,covering their synthesis,intriguing properties,and various applications in electroluminescence and electronic devices,as well as in biosensors,etc.We hope that this timely review will stimulate new research interest in this unique family of materials and promote their optoelectronic applications.

关键词： Acenes Boron Heteroacenes Luminophores Multi-color emission Light-emitting devices Organic optoelectronics Organicsemiconductors

Composition optimization, high-temperature stability, and thermal cycling performance of Sc-doped Gd_(2)Zr_(2)O_(7) thermal barrier coatings: Theoretical and experimental studies

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Journal of Advanced Ceramics 2022年第3期11卷 454-469页

作者： Lei guo Bowen LI Yuxian cheng Lu wang School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Advanced Joining Technology Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin 300072China AECC Shenyang Liming Aero-Engine Co. Ltd.Shenyang 110043China

Sc was doped into Gd_(2)Zr_(2)O_(7) for expanding the potential for thermal barrier coating (TBC) applications. The solid solution mechanism of Sc in the Gd_(2)Zr_(2)O_(7) lattice, and the mechanical and thermophysical properties of the doped Gd_(2)Zr_(2)O_(7) were systematically studied by the first-principles method, based on which the Sc doping content was optimized. Additionally, Sc-doped Gd_(2)Zr_(2)O_(7) TBCs with the optimized composition were prepared by air plasma spraying using YSZ as a bottom ceramic coating (Gd-Sc/YSZ TBCs), and their sintering behavior and thermal cycling performance were examined. Results revealed that at low Sc doping levels, Sc has a large tendency to occupy the lattice interstitial sites, and when the doping content is above 11.11 at%, Sc substituting for Gd in the lattice becomes dominant. Among the doped Gd_(2)Zr_(2)O_(7), the composition with 16.67 at% Sc content has the lowest Pugh’s indicator (G/B) and the highest Poisson ratio (σ) indicative of the highest toughness, and the decreasing trends of Debye temperature and thermal conductivity slow down at this composition. By considering the mechanical and thermophysical properties comprehensively, the Sc doping content was optimized to be 16.67 at%. The fabricated Gd-Sc coatings remain phase and structural stability after sintering at 1400 ℃ for 100 h. Gd-Sc/YSZ TBCs exhibit excellent thermal shock resistance, which is related to the good thermal match between Gd-Sc and YSZ coatings, and the buffering effect of the YSZ coating during thermal cycling. These results revealed that Sc-doped Gd_(2)Zr_(2)O_(7) has a high potential for TBC applications, especially for the composition with 16.67 at% Sc content.

关键词： thermal barrier coating(TBC) first-principles calculation solid solution mechanism high-temperature stability thermal cycling

Symmetries and bilinear equations for the modified BKP hierarchy

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Science China Mathematics 2023年第7期66卷 1529-1544页

作者： Weici guo Wenchuang Guan Shen wang Jipeng cheng School of Mathematics China University of Mining and TechnologyXuzhou 221116China

The modified Kadomtsev-Petviashvili hierarchy of B type(mBKP hierarchy)and its constrained cases are investigated from the aspect of the Lax formulation.Starting from the Lax equation of the mBKP hierarchy,we firstly derive the bilinear equations and show the existence of the tau functions.Then the additional symmetries are constructed,and the corresponding generator is showed to be the squared eigenfunction symmetry.After that,the actions of the additional symmetries on the tau functions are given.At last,the Lax formulation of the constrained mBKP hierarchy is investigated and the corresponding bilinear equations are also discussed.

关键词： mBKP hierarchy tau functions additional symmetries squared eigenfunction symmetries constrained mBKP hierarchy bilinear equations

Error Estimate of a New Conservative Finite Difference Scheme for the Klein-Gordon-Dirac System

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Numerical Mathematics(Theory,Methods and Applications) 2023年第1期16卷 140-164页

作者： Shasha Bian Yue cheng Boling guo Tingchun wang The Graduate School of China Academy of Engineering Physics Beijing 100088China School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Applied Physics and Computational Mathematics Beijing 100088China

In this paper,we derive and analyze a conservative Crank-Nicolson-type finite difference scheme for the Klein-Gordon-Dirac(KGD)system.Differing from the derivation of the existing numerical methods given in literature where the numerical schemes are proposed by directly discretizing the KGD system,we translate the KGD equations into an equivalent system by introducing an auxiliary function,then derive a nonlinear Crank-Nicolson-type finite difference scheme for solving the equivalent system.The scheme perfectly inherits the mass and energy conservative properties possessed by the KGD,while the energy preserved by the existing conservative numerical schemes expressed by two-level’s solution at each time step.By using energy method together with the‘cut-off’function technique,we establish the optimal error estimate of the numerical solution,and the convergence rate is O(τ^(2)+h^(2))in l∞-norm with time stepτand mesh size h.Numerical experiments are carried out to support our theoretical conclusions.

关键词： Klein-Gordon-Dirac equation nonlinear finite difference scheme conservation error analysis

Introducing a drought index to a crop model can help to reduce the gap between the simulated and statistical yield

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Atmospheric and Oceanic Science Letters 2018年第4期11卷 307-313页

作者： WANG Guo-Cheng ZHANG Qing XU Jing-Jing LAPC Institute of Atmospheric Physics Chinese Academy of Sciences

农田作物生产模型是一个用于评估众多环境和人为因子影响下作物产量变化的重要工具。然而,将所有与作物生长相关的环境因子考虑进模型中是不现实的。因此,模型往往会在一些极端环境条件发生时高估作物的产量。在本文中,我们试图将一个... 详细信息

农田作物生产模型是一个用于评估众多环境和人为因子影响下作物产量变化的重要工具。然而,将所有与作物生长相关的环境因子考虑进模型中是不现实的。因此,模型往往会在一些极端环境条件发生时高估作物的产量。在本文中,我们试图将一个干旱指数(SPEI)应用到一个农田生态系统过程模型(Agro-C)。同时,对比了模型是否考虑干旱指数的情况下与统计产量之间的差距;用于对比的统计产量是黄淮海平原各县近20年来的小麦和玉米统计数据。研究结果显示:在干旱发生的年份里,模型确实部分高估了作物产量;而在模型中加入干旱指数,则能够一定程度提高模型模拟干旱年份粮食作物的精度。

关键词： Agro-C model crop yield drought index

The selective adsorption of rare earth elements by modified coal fly ash based SBA-15

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Chinese Journal of Chemical Engineering 2022年第7期35卷 155-164页

作者： Jinglei Cui Qian wang Jianming Gao Yanxia guo Fangqin cheng State Environmental Protection Key Laboratory of Efficient Resource Utilization Techniques of Coal Waste Institute of Resources and Environmental EngineeringShanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related WastesShanxi UniversityTaiyuan 030006China

Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system.In this study,the species distribution of REE within the pH 0-8.0 was calculated.The SBA-15 originated from coal fly ash was modified by two steps with(3-aminopropyl)triethoxysilane(APTES)and diethylenetriaminepentaacetic dianhydride(DTPADA)to obtain DTPADA-SBA-15 adsorbent,which was applied to the selective adsorption of REE.The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE,including Eu,Gd,Tb,Nd and Sm,in acidic solution(pH 2)with multi competing ions.The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value.The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudosecond-order kinetic,of which the adsorption process followed the Langmuir isotherm model.

关键词： Rare earth elements Selective adsorption SBA-15 Modification

Numerical simulations of FPSO with sloshing tanks in a random freak waves

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Journal of Hydrodynamics 2022年第3期34卷 491-498页

作者： Yuan Zhuang guo wang De-cheng Wan Jian-wei Wu Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Marine Design and Research Institute of China Shanghai200011China Wuhan Second Ship Design and Research Institute Wuhan430205China

This paper presents a potential-viscous coupled method to simulate a floating production storage and offloading(FPSO)with two liquefied natural gas(LNG)sloshing tanks in a random freak wave.The potential theory uses high-order-spectral(HOS)method.The random wave is generated by HOS for 2000 s,and a freak wave is observed around 1830 s.The FPSO LNG model was firstly verified in regular waves using HOS-computational fluid dynamics(CFD)coupled method and validated the HOS-CFD coupled method can solve the ship motion coupled with sloshing tanks accurately.The FPSO with LNG tanks are then simulated in the freak wave,showed the coupling effects when the freak wave passes.With the existence of the sloshing tanks,the amplitude of the roll motion decreases and the period of roll motion changed.Wave breaking phenomenon can be observed when the wave crest of the freak wave encounters with the ship.

关键词： Ship motion with sloshing tank high-order-spectral-computational fluid dynamics(HOS-CFD)method naoe-FOAM-SJTU solver freak waves

Effect of die structure parameters on deformation behavior of bent tube in free bending process

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Journal of Iron and Steel Research(International) 2023年第3期30卷 487-503页

作者： Wei wang cheng cheng Li Wan Jie Tao Xun-zhong guo Chun-mei Liu College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211100JiangsuChina State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074HubeiChina Capital Aerospace Machinery Corporation Beijing 100076China

The bending section of tube between the bending die and the guider is in a less constrained state during the free bending process.The free bending dies have the important impact on the plastic deformation behavior and the forming quality of tube.To study the evolution law of the deformation behavior of tube with the die structure parameters and optimize the free bending die parameters,the free bending experiments and the corresponding numerical simulations were carried out.The design principle of free bending die was illustrated.The free bending experiment was conducted to verify the reliability of the numerical simulation method.Based on the numerical simulation results,the influence of the distance between the center point of bending die and the front end of guider on the forming quality of bent tube is more obvious than that of the fillet of guider.However,the fillet of bending die hardly affects the stress and strain distribution and the evolution of the wall thickness.Finally,the free bending experiments with the newly determined free bending dies were conducted.The ultimate bending radius of bent tube is reduced and the forming quality is improved.

关键词： Free bending Die structure parameter Forming quality Numerical simulation Tube

Laparoscopic liver resection for hepatocellular carcinoma complicated with significant portal hypertension:A propensity score-matched survival analysis

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Hepatobiliary & Pancreatic Diseases International 2023年第4期22卷 358-365页

作者： Zhang-You guo Yuan Hong Bing Tu Yao cheng Xiao-Mei wang Department of Minimally Invasive Interventional Therapy Yunnan Cancer HospitalThe Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer CenterKunming 650118China Medical Laboratory The First Affiliated Hospital of Kunming Medical UniversityInstitute of Experimental Diagnostics of Yunnan ProvinceKey Laboratory of Laboratory Medicine of Yunnan ProvinceKunming 650032China Department of Hepatobiliary Surgery The Second Affiliated HospitalChongqing Medical UniversityChongqing 400010China

Background: Significant portal hypertension(SPH) is a relative contraindication for patients with resectable hepatocellular carcinoma(HCC). However, increasing evidence indicates that liver resection is feasible for HCC patients with SPH. Methods: HCC patients with cirrhosis who underwent laparoscopic liver resection(LLR) in two centers from January 2013 to April 2018 were included. Surgical and survival outcomes were analyzed to explore potential prognostic factors. Propensity score matching(PSM) analysis was performed to minimize bias. Results: A total of 165 patients were divided into two groups based on the presence(SPH, n = 76) or absence(non-SPH, n = 89) of SPH. Patients in the SPH group had longer operative time, more blood loss, and more advanced TNM stage than patients in the non-SPH group( P 0.05). After PSM, alpha-fetoprotein(AFP) ≥ 400 μg/L [hazard ratio(HR) = 4.71, 95% confidence interval(CI): 2.69-8.25], ascites(HR = 2.18, 95% CI: 1.30-3.66), American Society of Anesthesiologists(ASA) classification(Ⅲ vs. Ⅱ)(HR = 2.13, 95% CI: 1.11-4.07) and tumor diameter > 5 cm(HR = 3.91, 95% CI: 2.02-7.56) independently predicted worse OS. Conclusions: LLR for patients with HCC complicated with SPH appears feasible at the price of increasing operative time and blood loss. AFP, ascites, ASA classification and tumor diameter may predict the prognosis of HCC complicated with SPH after LLR.

关键词： Hepatocellular carcinoma Significant portal hypertension Laparoscopic liver resection Propensity score matching analysis