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Journal of Energy Chemistry 2024年第10期97卷 612-621页

作者： Chenxi Xu Liang Chen Haihui Zhou shifeng qin Zhaohui Hou Yangyang Chen Jiale Sun Junwei Xu Zhongyuan Huang College of Chemistry and Chemical Engineering Hunan University College of Materials Science and Technology Central South University of Forestry and Technology Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials School of Chemistry and Chemical Engineering Hunan Institute of Science and Technology

Though Zn-air batteries(ZABs) are one of the most promising system for energy storage and conversion,challenge still persists in its commercial application due to the sluggish kinetics of oxygen reduction/evolution reaction(ORR/OER).Hereby,a polyvinylidene fluoride(PVDF)-assisted pyrolysis strategy is proposed to develop a novel corrugated plate-like bifunctional electrocatalyst using two-dimensional zeolitic imidazolate frameworks(2D ZIF-67) as the *** employed PVDF plays an important role in inheriting the original 2D structure of ZIF-67 and modulating the composition of the final *** a result,a corrugated plate-like electrocatalyst,high-density Co nanoparticles decorated 2D Co,N,and F tri-doped carbon nanosheets,can be *** acquired electrocatalyst enables efficient active sites and rapid mass transfer simultaneously,thus showing appreciable electrocatalytic performance for rechargeable Zn-air ***,our proposed strategy offers a new perspective to the design of advanced oxygen electrocatalysts.

关键词： Active sites Corrugated plate Mass transfer Oxygen electrocatalyst Zn-air batteries

Snow Information Abstraction Based on Remote Sensing Data： Taking the North of Xinjiang for Example

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Geo-Spatial Information Science 2009年第1期12卷 56-60页

作者： PEI Huan FANG shifeng LIU Zhihui qin Zhihao International Institute for Earth System Science Nanjing University 22 Hankou Road Nanjing 210093 China.

This paper proposes an applicable approach for snow information abstraction in northern Xinjiang Basin using MODIS data. Linear spectral mixture analysis （LSMA） was used to calculate snow cover fractions （SF） within a pixel, which was used to establish a regression function with NDSI. In addition, 80 snow depths samples were collected in the study region. The correlation between image spectra reflectance and snow depth as well as the comparison between measured snow spectra and image spectra was analyzed. An algorithm was developed for snow depth inversion on the basis of the correlation between snow depth and snow spectra in the region. The results indicated that the model of SF had a high accuracy with the mean absolute error 0.06 tested by 26 true measured values and the validation for snow depth model using another dataset with 50 sampling sites showed an RMSE of 1.63. Our study showed that MODIS data provide an alternative method for snow information abstraction through development of algorithms suitable for local application.

关键词： snow information MODIS satellite data snow cover snow fraction snow depth

An Initial Analysis on Current Situation of English Teaching in Agricultural Colleges in Remote Area

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西昌学院学报(自然科学版) 2000年第3期 60-61+59页

作者： qin shifeng Yang Ruping (Xichang Agricultural College,Xichang,Sichuan 615013)

This paper firat briefly introduces the general situation of Englishteaching system in *** it gives a detailed analysis on the present situa-tion of English teaching and studying in agricultural colleges such as our c... 详细信息

关键词： Current Situation English Teaching Agricultural College Examination

An Initial Analysis on Current Situation of English Teaching in Agricultural Colleges in Remote Area

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西昌农业高等专科学校学报 2000年第3期14卷 60-61,59页

作者： qin shifeng Yang Ruping (Xichang Agricultural College,Xichang,Sichuan 615013)

关键词：中国农业大学英语教学网络区域分布

聚羧酸高性能减水剂在万家口子水电站双曲拱坝碾压混凝土中的研究及应用

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红水河 2020年第1期39卷 131-133页

作者：覃仕锋中国能源建设集团广西水电工程局有限公司

鉴于万家口子水电站碾压混凝土胶凝材料品种、来源和性能波动大,常用的萘系减水剂无法与不同的胶凝材料全部适应,笔者所在的研究团队根据现场施工条件和要求,使用具有超强保坍性能和超强减水性能的聚羧酸母液和其他组分复配,研发一种能... 详细信息

鉴于万家口子水电站碾压混凝土胶凝材料品种、来源和性能波动大,常用的萘系减水剂无法与不同的胶凝材料全部适应,笔者所在的研究团队根据现场施工条件和要求,使用具有超强保坍性能和超强减水性能的聚羧酸母液和其他组分复配,研发一种能满足实际施工要求的聚羧酸高性能减水剂,其满足与多种胶凝材料的适应性和现场施工性能要求,降低胶凝材料用量,减少混凝土水化热。聚羧酸高性能减水剂在实际应用中取得了良好的技术效果和经济效益。

关键词：聚羧酸高性能减水剂碾压混凝土双曲拱坝万家口子水电站

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16Mn钢板焊接缺陷的声发射检测

无损检测 1987年第3期9卷 64-65页

作者：刘时风周金华秦平彦劳动人事部锅炉压力容器检测研究中心

本实验目的是评价声发射技术检测16Mn钢焊接缺陷的能力。通过带各种缺陷试样拉伸试验声发射监测的试验结果表明:声发射技术能在材料屈服前检测出16Mn钢中大尺寸和尖锐形状的焊接缺陷声发射技术对于检测严重焊接缺陷是有效的。

关键词：拉伸试验钢焊接抗拉试验材料试验声发射技术声发射检测 Mn

A novel multi-state bogie system reliability evaluation approach by extended d-MC model for high-speed trains

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Transportation Safety and Environment 2024年第3期6卷 35-46页

作者： Yong Fu Ruoqu Liu Jisheng Dai Wenlong Zhu Xin Liu Yong qin Zhuzhou CRRC Times Electric Co. Ltd.Times RoadShifeng DistrictZhuzhouHunan 412001China Department of Statistics University of WarwickCoventry CV47ALUnited Kingdom State Key Lab of Rail Traffic Control&Safety Beijing Jiaotong UniversityHaidian DistrictBeijing 100044China

Bogie is a pivotal system and plays a critical part in the safety and reliability management of high-speed ***,the available bogie system reliability analysis methods lack the consideration of multi-state characteristics,and the common multi-state reliability analysis methods,being an NP-hard problem,lead to low *** order to overcome these drawbacks,this paper proposes a novel multi-state rail train bogie system reliability analysis approach based on the extended d-MC *** different function interactions within the bogie system are considered to build the multi-state bogie system flow network ***,an extended d-MC model is established to remove unnecessary d-MC candidates and duplicates,which greatly enhances the computing *** bogie system reliability is calculated,and examples are *** experiments are carried out for the different operational conditions of the bogie system and are used to test the practicability of the method proposed in this article;it is found that this method outperforms a newly developed method in solving multi-state reliability problems.

关键词： multi-state system reliability bogie flow network extended d-MC model

咸阳市2018-2022年柯萨奇A组16型病毒序列分析

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病毒学报 2024年第2期40卷 418-423页

作者：王士峰秦龙李珍妮王丽娟张丹霞蒋宇婷咸阳市疾病预防控制中心咸阳712000

本研究旨在了解咸阳市2018-2022年手足口病(Hand, foot and mouth disease, HFMD)病原柯萨奇A组16型(Coxsackievirus A16, CV-A16)基因进化特征,为HFMD防控策略制定提供依据。首先分析2018-2022年咸阳市HFMD监测数据,再选取部分CV-A16阳性样本进行RT-PCR扩增VP1基因序列,测序后进行系统进化和序列相似性分析。2018-2022年咸阳市CV-A16阳性确诊病例共计402例,占实验室确诊病例总数的28.69%(402/1401)。VP1序列系统进化分析显示选取的54条CV-A16 VP1均为B1基因亚型,25条属B1a型,29条属B1b型。2018-2020年以B1b型为主,而2021-2022年主要为B1a型。氨基酸序列相似性分析表明,B1a型序列存在T164K(25/25)、I251V(25/25)和A22T(3/25)三处突变,而B1b型主要有N14S(9/29)和I235V(6/29)突变。CV-A16为咸阳市2018年、2019年、2021年和2022年HFMD主要致病原之一,2021年后优势毒株可能已由B1b型转化为B1a型,将来应加强CV-A16基因型动态监测。

关键词：手足口病柯萨奇病毒A组16型 VP1序列进化分析

Geochemical characteristics of Dongsheng sandstone-type uranium deposit, Ordos Basin

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Chinese Journal Of Geochemistry 2007年第3期26卷 235-243页

作者： SUN Yuzhuang LIU Chiyang DAI shifeng qin Peng Key Laboratory of Resource Exploration Research of Hebei Province ＂ Hebei University of Engineering Handan 056038 China Northwest University Xi＇an 710069 China China University of Mining and Technology Beijing 100083 China

Generally, sandstone-type uranium deposits can be divided into three zones according to their redox conditions: oxidized zone, ore zone and reduced zone. The Dongsheng uranium deposit belongs to this type. In order to study its geochemical characteristics, 11 samples were taken from the three zones of the Dongsheng uranium deposit. Five samples of them were collected from the oxidized zone, four samples from the ore zone and two samples from the reduced zone. These samples were analyzed using organic and inorganic geochemical methods. The results of GC traces and ICP-MASS indicate that the three zones show different organic and inorganic geochemical characteristics.

关键词：砂岩铀堆积物鄂尔多斯岩

Effect of the precipitation state on high temperature tensile and creep behaviors of Mg-15Gd alloy

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Journal of Magnesium and Alloys 2022年第12期10卷 3459-3469页

作者： Shuxia Ouyang Guangyu Yang He qin Chunhui Wang shifeng Luo Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

Due to the effective precipitation strengthening effect of the β phase, Mg-Gd alloys exhibit excellent room temperature mechanical behaviors. However, when served at high temperatures, the metastable β phase will transform to other phases, resulting in severe performance degradation. In this study, we investigated the effect of precipitation state achieved by different heat treatments on high temperature tensile and creep behaviors of the Mg-15Gd alloy by comparing the properties of the as-cast, solid-solutioned(T4) and peak-aged(T6) alloys. The results showed that the tensile mechanical properties of the T6 alloy were always highest from room temperature to 300 ℃, in spite of an abnormal strength increase with temperature existed in the T4 alloy. For tensile creep properties, the T6 alloy exhibited the lowest steady creep rate below 235 ℃ while the T4 alloy possessed the best properties above 260 ℃. Microstructure characterization revealed that the transition was caused by the stress-promoted precipitation of β phase in the T4 alloy and rapid phase transformation in the T6 alloy at high temperatures. At 260 ℃, the calculated stress exponent n was 3.1 and 2.8 for the T4 and T6 alloys, respectively, suggesting the creep deformation mechanism was dislocation slip, which was further confirmed by the microstructure after creeping. Our findings can provide new insights into the heat treatment process of Mg-Gd alloys served at high temperatures.

关键词： Mg-Gd alloys Precipitation state High temperature tensile properties Tensile creep behaviors Stress-promoted precipitation