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Enhancing low-temperature NO_x storage and reduction performance of a Pt-based lean NO_x trap catalyst

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Rare Metals 2019年第1期38卷 81-86页

作者： Tong wang Li-Wei jia Xiu-Ting wang Gang wang Fu-Qiang Luo jia-ming wang School of Automotive and Traffic Engineering Jiangsu University Wuxi Weifu Environmental Catalysts Co. Ltd

Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(< 250℃) NO_x storage and reduction performance. The influence of the form of ceria on low-temperature NO_x storage and reduction performance of LNT catalysts was investigated with the focus on NO_x storage capacity, NO_x reduction efficiency during lean/rich cycling, product selectivity and thermal *** coupled plasma-atomic emission spectrometry(ICP-AES), Brunner-Emmet-T eller(BET), H_2-pulse chemisorption and X-ray diffraction(XRD) were conducted to characterize the physical properties of LNT catalysts. NO_x storage capacity and NO_x conversion efficiency were measured to evaluate NO_x storage and reduction performance of LNT catalysts. Pt/BaO/CeO_2-Al_2O_3 catalyst exhibits higher NO_x storage capacity than Pt/BaO/CeO_2 + Al_2O_3 catalyst in the temperature range of 150-250 ℃. Meanwhile, Pt/BaO/CeO_2-Al_2O_3 catalyst shows better NO_x conversion efficiency and N_2 selectivity. XRD results indicate that the thermal stability of CeO_2-Al_2O_3 complex oxide is superior to that of pure CeO_2. H_2-pulse chemisorption results show that Pt/BaO/CeO_2-Al_2O_3 catalyst has higher Pt dispersion than Pt/BaO/CeO_2 + Al_2O_3 catalyst over fresh and aged samples. The improved physical properties of Pt/BaO/CeO_2-Al_2O_3 catalyst are attributed to enhance the NOx storage and reduction performance over Pt/BaO/CeO_2 + Al_2O_3 catalyst.

关键词： NOx storage and reduction Low temperature Ceria Ceria-alumina LNT

Si/TiO_(2) carbon fiber core encapsulated in hierarchical multiple MXene@Co-MoS_(2) shells for constructing a free-standing anode of lithium storage

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Rare Metals 2024年第9期43卷 4222-4233页

作者： Xian-ping Du Ying Huang jia-ming wang Zhen-he Feng Xu Sun MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shanghai Institute of Space Power-Sources Shanghai 200245China Ningbo Institute of Northwestern Polytechnical University Ningbo 315103China

Silicon-based(Si-based) materials offer more possibilities for generating new portable electronic devices due to their high specific capacities. However, their inferior electrical conductivity and volume expansion during cycling seriously limit their development. The optimum solution is to select specific materials to establish an exceptionally conductive and volume buffer structure,which can assist Si materials in developing their excellent lithium storage properties. In this study, Si particles were confined in TiO_(2)carbon fibers(TiO_(2)CFs) via electrospinning, after which they were encapsulated with MXene and Co-MoS_(2)(CMS) nanosheets to fabricate hierarchical ST-2@MXene@CMS films. TiO_(2)CF, MXene and CMS were employed to establish a coherent conductive network with one-, two-and three-dimensional electronic pathways to permit the unimpeded flow of electrons inside the electrode material. TiO_(2)CF, MXene and CMS acted precisely as multilayered buffers to ameliorate the volume change of Si particles during cycling. In addition, the CMS nanosheets were involved in lithium storage, contributing to the final electrochemical performance. Ultimately, the ST-2@MXene@CMS films served as free-standing electrodes, avoiding the impact of inactive interfaces on the electrochemical performance and fulfilling the lightweight requirement for new energy storage devices.

关键词： Si particles MXene Co-MoS_(2)nanosheets Hierarchical structure Lithium-ion batteries

Crevice Corrosion Performance of 436 Ferritic Stainless Steel Studied by Different Electrochemical Techniques in Sodium Chloride Solutions with Sulfate Addition

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 815-822页

作者： jia-ming wang Sheng-Sheng Qian Yuan-Yuan Liu Yang-Ting Sun Yi-ming jiang Jin Li Department of Materials Science Fudan University

The crevice corrosion behaviors of 436 stainless steels in chloride-containing solutions with sulfate addition were studied using potentiodynamic, galvanostatic and repassivation potential measurements. The results of these electrochemical tests were compared and discussed. Galvanostatic test was proved to be the most powerful technique in detecting the crevice corrosion of 436 stainless steels, while the repassivation potential measurement was the most time-saving method in this study. Sulfate ions have inhibited the crevice corrosion of 436 stainless steels in chloride-containing solution, which may result from the effects of competitive adsorption and the IR drop mechanism.

关键词： Crevice corrosion Ferritic stainless steels Electrochemical techniques Sulfate ions Competitive adsorption IR drop mechanism

Pricing Guaranteed Minimum Death Benefits with Dollar Cost Averaging Under Time-changed Le′vy Models

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Acta Mathematicae Applicatae Sinica 2024年

作者： jia-ming wang Mei-qiao AI Zhi-min ZHANG College of Mathematics and Statistics Chongqing University

In this paper, we propose an efficient and accurate method for pricing Guaranteed Minimum Death Benefit (GMDB) under time-changed Le′vy processes. Suppose that the GMDB payoff depends on a dollar cost averaging (DCA) style periodic investment, and the activity rate process in stochastic time change is modeled by a square-root process. We develop a recursive method to derive the closed form valuation formula by using the frame duality projection method. Numerical examples are reported for demonstrating the effectiveness of our approach and illustrating the interplay between contract parameters and the valuation.

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基于伴随求解的核主泵轴向力优化方法（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2019年第11期20卷 852-863页

作者： jia-ming wang Peng-fei wang Xu ZHANG Xiao-dong RUAN Xin FU State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Engineering Zhejiang University City CollegeHangzhou 310015China

目的:核主泵轴向力过大容易造成水润滑轴承磨损,因此在保证扬程和效率性能的同时需要降低核主泵轴向力。本文旨在建立目标性能与叶轮几何形状的函数关系,探究基于伴随求解的扭曲叶轮的变形方案,在保证扬程不变的条件下同步优化叶轮的轴... 详细信息

目的:核主泵轴向力过大容易造成水润滑轴承磨损,因此在保证扬程和效率性能的同时需要降低核主泵轴向力。本文旨在建立目标性能与叶轮几何形状的函数关系,探究基于伴随求解的扭曲叶轮的变形方案,在保证扬程不变的条件下同步优化叶轮的轴向力和效率,并找到影响该综合性能的叶轮关键区域。创新点:1.提出一种同步改进多个目标性能的叶轮形状优化方法;2.将伴随求解和径向基函数网格变形相结合以实现核主泵叶轮三维曲面优化。方法:1.通过理论分析,建立基于径向基函数网格变形的伴随优化方法,并在开源平台编写迭代程序;2.通过公式推导,构建扬程、效率和轴向力对应的目标函数(公式(19)^(21)),并运用正交实验确定各个目标函数的参数因子;3.通过迭代计算,在保证扬程不变的条件下实现轴向力和效率的同步优化,确定影响该综合性能的关键区域(图8),并获得叶轮的改进设计方案;4.通过流场分析,对比改进前后流场内部的压力和流速分布情况(图9和10),并验证改进方案的可行性和有效性。结论:1.与传统的随机算法相比,该优化方法直接沿梯度方向进行迭代优化,可以避免使用大量样本数据来寻找优化路径;2.该优化方法将伴随求解和径向基函数网格变形相结合,实现了流场计算和结构变形的自动化,可以保证流场网格光滑高效地更迭;3.叶轮靠近出口边的下半部分是同步优化核主泵轴向力和效率的关键区域。

关键词：核主泵伴随方法径向基函数轴向力形状优化

Effect of inflammatory response on joint function after hip fracture in elderly patients:A clinical study

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World Journal of Orthopedics 2024年第4期15卷 337-345页

作者： jia-ming wang Yu-Tao Pan Chen-Song Yang ming-Chong Liu Sheng-Chao Ji Ning Han Fang Liu Gui-Xin Sun Department of Traumatic Surgery Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200092China

BACKGROUND Excellent hip joint function facilitates limb recovery and improves the quality of *** study aimed to investigate the potential risk factors affecting postoperative joint functional activity and outcomes in elderly hip fractures patients and to provide evidence for patient rehabilitation and clinical *** To explore the relationship between inflammatory factors and hip function and the interaction between inflammation and health after hip fracture in elderly *** The elderly patients who had hip fracture surgery at our hospital between January 1,2021,and December 31,2022 were chosen for this retrospective clinical *** with excellent and fair postoperative hip function had their clinical information and characteristics gathered and ***,gender,fracture site,surgical technique,laboratory indices,and other variables that could have an impact on postoperative joint function were all included in a univariate *** further identify independent risk factors affecting postoperative joint function in hip fractures,risk factors that showed statistical significance in the univariate analysis were then included in a multiple logistic regression *** addition to this,we also compared other outcome variables such as visual analogue scale and length of hospital stay between the two *** A total of 119 elderly patients with hip fractures were included in this study,of whom 37 were male and 82 were *** results of univariate logistic regression analysis after excluding the interaction of various factors showed that there was a statistically significant difference in interleukin(IL)-6,IL-8,IL-10,C-reactive protein(CRP),and complement C1q(C1q)between the fair and excellent joint function groups(P20 pg/mL[Odds ratio(OR)3.070,95%CI:1.243-7.579],IL-8>21.4 pg/mL(OR 3.827,95%CI:1.498-9.773),CRP>10 mg/L(OR 2.142,95%CI:1.

关键词： Hip function Fracture Inflammatory factors Risk factors Prevention

Difference in failure patterns of pT3-4N0-3M0 esophageal cancer treated by surgery vs surgery plus radiotherapy

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World Journal of Gastrointestinal Oncology 2019年第12期11卷 1172-1181页

作者： Ya Zeng Wen Yu Qi Liu Wei-Wei Yu Zheng-Fei Zhu Wei-Xin Zhao Jun Liu jia-ming wang Xiao-Long Fu Yuan Liu Xu-Wei Cai Department of Radiation Oncology Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200030China Department of Radiation Oncology Fudan University Shanghai Cancer CenterShanghai 200030China Department of Radiation Oncology Shanghai Jiao Tong University Affiliated Shanghai Sixth People’s HospitalShanghai 200030China Department of Statistics Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200030China

BACKGROUND There has been no study comparing the difference in the failure patterns between patients with or without postoperative radiotherapy(PORT)after esophagectomy for pT3-4N0-3M0 esophageal squamous cell carcinoma(ESCC).AIM To investigate the difference in the failure patterns of stage pT3-4N0-3M0 ESCC patients with or without *** Patients with stage pT3-4N0-3M0 ESCC,who underwent surgery with or without PORT,were enrolled in this *** primary endpoint was to investigate the difference in the failure patterns between patients with or without PORT after *** secondary endpoint was to estimate whether patients with stage pT3-4 ESCC could achieve a disease-free survival(DFS)advantage after receiving adjuvant *** analyses were performed by the Kaplan-Meier method,Cox regression model,and Chi-squared test or Fisher’s exact *** In total,230 patients with stage pT3-4N0-3M0 ESCC were included in this ***-six patients who received PORT were screened from a prospective cohort(S+R arm).And 174 patients involving surgery alone were retrospectively selected from July 2006 to October 2014(S arm).There were no significant differences in the clinical or pathological characteristics of patients between the two arms,except for tumor location(P=0.031).The failure patterns between the two arms were significantly different(P<0.001).Patients in the S arm had a significantly higher proportion of locoregional recurrence and a lower proportion of distant metastasis than those in the S+R arm(92.0%vs 35.7%,P<0.001 and 19.0%vs 75.0%,P<0.001,respectively).The difference in the median DFS between the two arms was statistically significant(12.7 vs 8 mo,P=0.048).Univariate analysis and multivariate analysis both demonstrated that the number of lymph node metastases≥3(HR=0.572,95% CI:0.430-0.762,P<0.001)was an independent poor prognostic factor for DFS in patients with stage pT3-4N0-3M0 *** PORT could improve DFS and local c

关键词： Esophageal squamous cell carcinoma Postoperative radiotherapy Failure patterns Disease-free survival

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie jia-Lin Li Ling Gong Xiang-Li Zhong Hong-jia Song Jin-Bin wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance