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稀土学报:英文版 2023年第9期41卷 1385-1391,I0004页

作者： Xiaoqian Xu yurun feng Zhaoyu Zhong Xue Guo Zhenhao Zhang Jiao Li Shikai Zhao Shigang Wu Haibin Sun School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China Shandong Yasai Ceramic Technology Co. Ltd.Jinan 271100China Shandong Industrial Ceramics Research&Design Institute Co. Ltd.Zibo 255000China

High-performance solid oxide fuel cell(SOFC) is in urgent need of high-quality electrolyte powders with high reactivity and chemical uniformity.Here,8 mol% Y_(2)O_(3) doped ZrO_(2)(YSZ) nano-powders were synthesized by an improved solid-state reaction method at ambient temperature,and were applied to the fabrication of SOFC electrolytes.YSZ nano-powders show average grain sizes of ^(2)0 nm and high dispersibility,which is comparable with or even better than some other chemical methods.Benefitting from their high reactivity,dense YSZ electrolytes(relative density of 97.9%) can be obtained at a relatively low sintering temperature of 1400℃.The optimized electrical conductivity reaches up to a high value of0.034 S/cm at 800 0C in air.The anode supported single cell with the construction of Ni-YSZ/YSZ/Sm_(0.2)Ce_(0.8)O_(2-δ)(SDC)/La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCF) exhibits the peak power density of 0.827 W/cm^(2) at800℃ while taking wet H_(2) as fuels and ambient air as oxidants.

关键词： Room temperature solid-state reaction YSZ electrolyte High sintering activity High ionic conductivity Rare earths

地震下RC空心墩弯-剪数值模型及混合试验验证

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防灾减灾工程学报 2024年第3期44卷 596-604页

作者：蒋雨润梅竹刘洋陈江熊峰四川大学建筑与环境学院四川成都610065 温州大学建筑工程学院浙江温州325035 中国地震局工程力学研究所地震工程与工程振动重点实验室黑龙江哈尔滨150080 滨海软土地基防灾减灾技术浙江省工程研究中心浙江温州325035

地震作用下钢筋混凝土空心截面中高桥墩多发生弯剪破坏,而其弯剪耦合反应的数值模拟方法尚不完善。针对当前弯剪串联模型中的剪切模型未考虑空心截面特征的问题,提出基于关键参数的剪切模型修正方法,并通过混合试验进行验证。分别从桥... 详细信息

地震作用下钢筋混凝土空心截面中高桥墩多发生弯剪破坏,而其弯剪耦合反应的数值模拟方法尚不完善。针对当前弯剪串联模型中的剪切模型未考虑空心截面特征的问题,提出基于关键参数的剪切模型修正方法,并通过混合试验进行验证。分别从桥墩的剪跨比、混凝土开裂后剪切刚度、等效截面面积、桥墩有效高度与墩身混凝土斜裂缝倾角等参数入手,提出剪切模型关键参数的修正方法;基于修正的开裂剪切强度、开裂剪切位移、剪切极限承载力及其对应的剪切位移与剪切破坏位移,提出适用于空心桥墩剪切性能模拟的三折线型骨架曲线建立方法;通过组合剪切模型与基于纤维单元的弯曲模型,建立空心墩弯剪耦合反应的数值模型;与一座空心高墩桥混合试验结果对比,其桥墩子结构的物理试验结果验证了数值模拟方法。分析表明:通过本文所提数值模拟方法得到的空心桥墩弯剪滞回曲线与真实地震加载路径下的试验曲线匹配良好,能够模拟空心墩在真实地震作用下的弯剪滞回行为。

关键词：钢筋混凝土空心墩弯-剪耦合剪切骨架模型地震响应模拟混合试验

Dielectric properties of porous SiC/Si3N4 ceramics by polysilazane immersion-pyrolysis

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Progress in Natural Science:Materials International 2019年第2期29卷 184-189页

作者： Xiao Lin Hongyu Gong Yujun Zhang Jianqiang Bi yurun feng Yu Liu Shan Wang Key Laboratory for Liquid-Solid Structural Evolution & Processing of Materials of Ministry of Education Shandong University Key Laboratory of Special Functional Aggregated Materials Ministry of Education Shandong University

The SiC nanotubes were synthesized on porous Si3N4matrix by polysilazane immersion-pyrolysis. The β-SiC and free C contents increased with the increasing dipping times, which cause some clear vibration and loss peaks of the dielectric constant patterns emerged at around 12.9 GHz and 14.7 GHz in the samples of 20 wt% and 30 wt%benzoic acid, respectively. The reflectivity of the obtained ceramics were -7 dB ～-10 dB from the frequency of 8 GHz–18 GHz, which means that the amount of 80%–90% electromagnetic wave could be attenuated. The ceramics containing 40 wt% benzoic acid showed the high loss, low reflectivity and a wide absorbing band,indicating the high absorbing efficiency and good dielectric properties.

关键词： SiC Si3N4 Dipping Dielectric properties

松嫩草甸草原植物群落物种组成和多样性对刈割和长期放牧的响应

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草业科学 2024年第2期41卷 271-283页

作者：卢彦达丰吉邵泽付国猛卢昱润李海燕中国地质调查局哈尔滨自然资源综合调查中心黑龙江哈尔滨150081

为明晰不同利用方式对松嫩草甸草原不同植物群落物种组成和多样性的影响,本研究通过对松嫩平原西部地带性植被草甸草原在刈割和长期放牧利用下两种典型群落-羊草(Leymus chinensis)群落和野古草(Arundinella hirta)群落的调查与分析,探... 详细信息

为明晰不同利用方式对松嫩草甸草原不同植物群落物种组成和多样性的影响,本研究通过对松嫩平原西部地带性植被草甸草原在刈割和长期放牧利用下两种典型群落-羊草(Leymus chinensis)群落和野古草(Arundinella hirta)群落的调查与分析,探究了两种利用方式对群落植物物种组成、重要值、生活型、数量特征及多样性等指标的影响。结果表明:刈割和长期放牧下羊草群落物种数为18种和21种,禾本科植物占比最高,分别为33.3%和45.45%;野古草群落物种数分别为39种和32种,禾本科植物占比为23.1%和21.9%。长期放牧增加羊草群落地面芽植物和野古草群落一年生植物占比,降低野古草群落地面芽植物占比。两种利用方式下两个群落饲用价值类型均以优良牧草的种类最多,占比分别为58.76%(刈割羊草群落)、53.33%(长期放牧羊草群落)、46.56%(刈割野古草群落)和46.63%(长期放牧野古草群落)。长期放牧显著降低了两个植物群落的盖度、高度和生物量(P <0.05)。与刈割相比,长期放牧下植物群落的Shannon-Wiener多样性指数和Simpson多样性指数均呈增加趋势。长期放牧下羊草群落和野古草群落S?rensen相似性指数更高,两个群落植物物种相似度更高;而Cody指数在刈割利用下更高,两个群落物种组成在刈割利用下的变化幅度更大。刈割和放牧对松嫩草甸草原不同植物群落的组成和多样性能够产生不同程度的影响,合理适度的利用方式和保护措施将更有利于对草原资源的可持续利用。

关键词：松嫩草原利用方式生活型饲用价值物种多样性群落物种相似性群落数量特征

Additive Manufacturing of Ceramics from Liquid Feedstocks

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Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers) 2022年第1期1卷 16-27页

作者： Giorgia Franchin Hamada Elsayed Renata Botti Kai Huang Johanna Schmidt Giulio Giometti Alice Zanini Anna De Marzi Marco D’Agostini Paolo Scanferla yurun feng Paolo Colombo Dipartimento di Ingegneria Industriale Universitàdi Padovavia Marzolo 935131 PadovaItaly Refractories Ceramics and Building Materials DepartmentNational Research CentreEl Buhouth Str.12622 CairoEgypt Department of Materials Science and Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA

In this review,we summarize the research activities carried out by our research group at the University of Padova on the additive manufacturing of ceramics from liquid feedstocks.Particularly,we evaluate the use of preceramic polymers,geopolymers,and sol-gel solutions.We mainly focus on processing with liquid feedstocks because they have some advantages with respect to slurry-based feedstocks in which powders are present.Particularly,lower viscosity,enhanced transparency,and lack of scattering and sedimentation are advantageous features for vat photopolymerization processes,whereas the absence of particulates reduces clogging problems at the nozzle for extrusion-based processes.Simultaneously,preceramic polymers and geopolymers have some limitations in terms of the range of ceramic compositions that can be obtained;sol-gel solutions are intrinsically unstable,whereas printed objects suffer from drying issues.Nevertheless,we successfully produced high-quality parts using a variety of additive manufacturing techniques,some of which(e.g.,volumetric additive manufacturing)have been proposed for the fabrication of ceramic components for the first time.

关键词： Additive manufacturing Preceramic polymers SiOC

2019—2022年郑州市人乳头瘤病毒疫苗疑似预防接种异常反应监测结果

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现代疾病预防控制 2024年第4期35卷 313-317页

作者：范张洁李锋许海燕王小丽原宏孟庆玉王萌王瑞王雨润姚莹莹乔丹郑州市疾病预防控制中心免疫规划所河南郑州450007

目的分析2019—2022年郑州市适龄女性接种人乳头瘤病毒(HPV)疫苗后出现疑似预防接种异常反应的发生情况。方法通过中国疾病预防控制信息系统收集2019—2022年郑州市报告的HPV疫苗疑似预防接种异常反应(AEFI)个案信息,通过河南省免疫规... 详细信息

目的分析2019—2022年郑州市适龄女性接种人乳头瘤病毒(HPV)疫苗后出现疑似预防接种异常反应的发生情况。方法通过中国疾病预防控制信息系统收集2019—2022年郑州市报告的HPV疫苗疑似预防接种异常反应(AEFI)个案信息,通过河南省免疫规划信息管理系统以及郑州市智慧公共卫生系统收集HPV疫苗接种剂次数据,采用描述性流行病学方法进行分析。结果2019—2022年郑州市HPV疫苗疑似预防接种异常反应的年均报告发生率为4.57/10万剂,HPV2、HPV4、HPV9的报告发生率分别为3.42/10万剂、3.55/10万剂、6.38/10万剂,差异有统计学意义(P<0.05)。一般反应、异常反应、偶合症的报告发生率分别为4.17/10万剂、0.30/10万剂、0.10/10万剂。新密市、荥阳市和金水区报告发生率较高,分别为11.78/10万剂、8.96/10万剂、8.94/10万剂。9~<17岁人群报告发生率较高,为11.37/10万剂;各月均有病例报告,4~<7月报告发生率最高,为6.99/10万剂,不同年龄组、不同月份报告发生率差异有统计学意义(P均<0.05)。AEFI病例全部在0~24 h发生,其中65.22%在接种后0~<12 h发生。接种HPV疫苗第2剂次后发生异常反应的占50.00%,12~24 h发生异常反应的占66.67%。结论郑州市2019—2022年HPV疫苗不良反应以一般反应为主,报告发生率低,预防接种安全性良好。

关键词：人乳头瘤病毒疫苗接种疑似预防接种异常反应监测

Extraction of Flavonoids from Leaves of Coix lacryma-jobi L.

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Medicinal Plant 2018年第1期9卷 9-12页

作者： Xiaoxiong feng yurun LIANG Aiyue LUO Jiandan NONG Shaomei MO Yan NING Suoyi HUANG College of Clinical Laboratory Medicine Youjiang Medical University for Nationalities College of Basic Medical Science Youjiang Medical University for Nationalities College of Pharmacy Youjiang Medicine University for Nationalities Key Laboratory of Guangxi Universities on National Medicine in Youjiang River Basin

[Objectives] To extract the flavonoids from leaves of Coix lacryma-jobi L. [Methods] Ethanol extraction method was adopted,spectrophotometry was used,and single factor experiment and orthogonal experiment were carried out to study the effects of ethanol percentage,extraction temperature,solid-to-liquid ratio and extraction time on the extraction of total flavonoids from leaves of C. lacryma-jobi L.[Results] The order of 4 factors influencing the extraction of flavonoids from leaves of C. lacryma-jobi L. was: solid-to-liquid ratio > extraction time > ethanol percentage > extraction temperature. When the extraction temperature was 70℃,the extraction time was 1. 5 h and the solid-liquid ratio was 1: 10,the ethanol percentage was 60%,the extraction effect was the best,extraction of flavonoids was 0. 107 5 mg/m L.[Conclusions] This study is expected to provide a theoretical basis for further development and utilization of C. lacryma-jobi L.

关键词： Leaves of Coix lacryma-jobi L. Flavonoids Extraction Single factor experiment Orthogonal experiment

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基于深度卷积生成对抗神经网络预测气窜方向

中国石油大学学报（自然科学版） 2020年第4期44卷 20-27页

作者：冯其红李玉润王森任佳伟周代余范坤中国石油大学(华东)石油工程学院山东青岛266580 非常规油气开发教育部重点实验室(中国石油大学(华东)) 山东青岛266580 中国石油塔里木油田公司勘探开发研究院新疆库尔勒841000

注气开发是目前油田开发最有效的EOR方法之一,但注气开发面临见气时间早、气体突进严重等一系列问题。通过气窜方向预测能够及时调整工作制度,避免问题发生。利用深度卷积对抗神经网络建立渗透率场和注气后气相饱和度分布的动态映射关系... 详细信息

注气开发是目前油田开发最有效的EOR方法之一,但注气开发面临见气时间早、气体突进严重等一系列问题。通过气窜方向预测能够及时调整工作制度,避免问题发生。利用深度卷积对抗神经网络建立渗透率场和注气后气相饱和度分布的动态映射关系,通过输入渗透率场的数据进行图像映射,得到不同时间的气相饱和度分布,预测气窜方向。结果表明:深度卷积方法在提取渗透率特征方面表现出良好性能;采用图像的结构相似性指数(SSIM)作为检验指标,将用对抗神经网络方法建立的气相饱和度分布与商业数值模拟器预测结果进行对比,二者结构相似度大于0.9;深度卷积生成对抗网络(DC-GAN)能够有效地预测注入气体在油藏中的气窜方向。

关键词：深度卷积对抗神经网络结构相似性指数气相饱和度