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Effect of Heat Input on Microstructure and Toughness of Coarse Grain Heat Affected Zone in Nb Microalloyed HSLA Steels

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Journal of Iron and Steel Research International 2009年第5期16卷 73-80页

作者： zhang ying-qiao zhang Han-qian LI Jin-fu LIU Wei-ming Department of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China Research Institute for Advanced Structural Steel Research and Development Center Baoshan Iron and Steel Limited Company Shanghai 201900 China

The influence of Nb on microstructure, mechanical property and the transformation kinetics of the coarse grain heat affected zone （CGHAZ） in HSLA steels for different heat inputs, has been investigated. When welded at higher heat inputs （100-60 kJ/cm）, impact toughness values of the steel without Nb are much higher than those of the steel with Nb, and the lowest span is 153 J at 60 kJ/cm. But only a little higher values are observed at lower heat inputs （40-30 kJ/cm）, and the highest span is 68 J at 30 kJ/cm. Dilatation studies indicate that continuous cooling transformation starting temperatures （Ts） of CGHAZ for the steel with Nb are approximately 15-30℃ which are lower than those of the steel without Nb at all heat inputs. For higher heat inputs, Nb in solid solution suppresses ferrite transformation and promotes the formation of granular bainite which has detrimental effect on impact toughness. For lower heat inputs higher Charpy impact energy values in the steel with Nb are associated with the formation of low carbon self-tempered martensite.

关键词： HSLA steel coarse grain heat affected zone heat input Niobium impact toughness

Non-Metallic Inclusion Distribution in Surface Layer of IF Steel Slabs

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Journal of Iron and Steel Research International 2008年第1期15卷 70-74页

作者： zhang qiao-ying WANG Li-tao WANG Xin-hua LI Hong WANG Wan-jun School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Shougang Iron and Steel Corporation Ltd Beijing 100041 China

Non-metallic inclusion distribution in the surface layer of IF steel slabs during unsteady casting was investigated using the original position statistic distribution analysis（OPA）*** was found that most non-metallic inclusions larger than 10 μm existed in the subsurface layers of 0.5-3.5 mm from the slab surfaces and very few large non-metallic inclusions were found in the inner regions（≥4.5 mm from slab surfaces）.In addition,it was found that at high casting speed level（1.4 m/min）,even a slight change of casting speed could result in a remarkable increase of the non-metallic ***,at high casting speed,changing the casting speed should be avoided or considerably lower speed changing rate must be used.

关键词： IF steel transient casting slab surface layer non-metallic inclusion

嘉陵江生态环境研究回顾与展望——基于文献计量的可视化分析

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西华师范大学学报（自然科学版） 2024年第1期45卷 9-16页

作者：谭晶华张运春张桥英王溢琛陈馨西华师范大学地理科学学院四川南充637009 西华师范大学环境科学与工程学院四川南充637009 西华师范大学四川省干旱河谷土壤侵蚀监测与控制工程实验室四川南充637009 西华师范大学嘉陵江流域研究所四川南充637009

嘉陵江是长江举足轻重的一条支流,是沿岸地区融入长江经济带的纽带,也是沿岸城市发展和居民生活必不可少的生态资源。因此,嘉陵江生态环境的研究受到了广大学者的关注。文章检索了中国知网(CNKI)数据库和Web of Science(WOS)核心数据库... 详细信息

嘉陵江是长江举足轻重的一条支流,是沿岸地区融入长江经济带的纽带,也是沿岸城市发展和居民生活必不可少的生态资源。因此,嘉陵江生态环境的研究受到了广大学者的关注。文章检索了中国知网(CNKI)数据库和Web of Science(WOS)核心数据库关于嘉陵江生态环境研究的论文,分别得到了347篇和62篇,利用CiteSpace软件进行可视化分析,从发文量、核心作者、主要机构和关键词等方面进行了探讨。结果表明:随着时间发展,发文量总体呈上升趋势,在2021年达到最高;论文发表的主要机构是西华师范大学、西南大学和重庆大学。CNKI数据库(1979—2021)中显示,研究区域主要分为嘉陵江上游、中游和下游地区,研究主题集中在植被的本底调查、水质条件、评价等方面;WOS数据库最近10年(2011—2021)的论文可分为三大类,第一类是对生物(主要是鱼类)的研究,第二类是对污染的研究,第三类是研究方法;大量生态模型以及3S技术被应用在嘉陵江流域的研究中,研究主题主要是风险评价、污染等方面。同时结合2个数据库的结果发现,学者们都重点关注嘉陵江水质条件和评价等方面,并研究了嘉陵江对三峡库区水环境的影响。在当前国家高度重视生态环境保护及重点关注长江经济带发展的大背景下,文章为未来对于嘉陵江流域的研究提出了一些研究方向。

关键词：保护长江流域三峡 CNKI WOS CiteSpace

Potential role of hippocampal neurogenesis in spinal cord injury induced post-trauma depression

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Neural Regeneration Research 2024年第10期19卷 2144-2156页

作者： ying Ma Yue qiao Xiang Gao Spinal Cord and Brain Injury Research Group Stark Neuroscience Research InstituteIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neurology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

It has been reported both in clinic and rodent models that beyond spinal cord injury directly induced symptoms, such as paralysis, neuropathic pain, bladder/bowel dysfunction, and loss of sexual function, there are a variety of secondary complications, including memory loss, cognitive decline, depression, and Alzheimer's disease. The largescale longitudinal population-based studies indicate that post-trauma depression is highly prevalent in spinal cord injury patients. Yet, few basic studies have been conducted to address the potential molecular mechanisms. One of possible factors underlying the depression is the reduction of adult hippocampal neurogenesis which may come from less physical activity, social isolation, chronic pain, and elevated neuroinflammation after spinal cord injury. However, there is no clear consensus yet. In this review, we will first summarize the alteration of hippocampal neurogenesis post-spinal cord injury. Then, we will discuss possible mechanisms underlie this important spinal cord injury consequence. Finally, we will outline the potential therapeutic options aimed at enhancing hippocampal neurogenesis to ameliorate depression.

关键词： antidepressants chronic pain depression exercise hippocampal neurogenesis inflammation inhibition neuroinflammation physical activity deficits social isolation spinal cord injury

A visible-light-assisted Pd/TiO_(2)gas sensor with carbon nanotubes electrodes for trace formaldehyde detection

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Rare Metals 2024年第1期43卷 257-266页

作者： Can Liu qiao-qiao Zou Bin Liu Yong zhang School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Owing to the ppb-level detection standard toward the toxic and harmful gas,the detection of trace gases has become an important subject in the field of indoor environment ***,the traditional resistive gas sensors hardly meet the requirement due to the weak signal generated by trace gas molecules that are difficult to ***,a visible-light-assisted Pd/TiO_(2)gas sensor is proposed to endow the effective detection of trace formaldehyde(HCHO)gas without heating *** from the enhanced photocatalytic properties of TiO_(2)by Pd decoration,the visible-light-assisted Pd/TiO_(2)gas sensor can detect the HCHO gas as low as80×10^(–9)at room *** successful preparation of nanoscale TiO_(2)sensing layer is facilitated by the ultrathin carbon nanotube interdigital electrode in the gas sensor,which avoids the discontinuity of the sensing layer caused by the excessive thickness of the traditional metal *** addition,the whole preparation process of the Pd/TiO_(2)gas sensor with carbon nanotube electrodes is compatible with mainstream CMOS fabrication technology,which is expected to realize the batch fabrication and micro-integrated application of gas *** is expected that our work can provide a new strategy for the batch preparation of high-performance trace HCHO gas sensors and their future applications in portable electronic devices such as smartphones.

关键词： Visible-light-assisted gas sensor Pd/TiO_(2) Trace HCHO detection Carbon nanotubes electrodes

TiO_(2)-Fe_(2)TiO_(5)heterostructure hollow spheres enable high-performance lithium-sulfur batteries via interfacial engineering

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Rare Metals 2024年第8期43卷 4006-4012页

作者： Kai-Tao Liu Hong-Qiang Wang Zhuo Chen Shi-Lin zhang ying-ying Song Fang Liu qiao-Ling Li Jiao Li School of Materials Science and Engineering Shandong University of TechnologyZibo 255049China College of Chemistry&Environmental Science Hebei UniversityBaoding 071002China School of Chemical Engineering Faculty of SciencesEngineering and TechnologyUniversity of AdelaideAdelaide 5005Australia School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China

The shuttle effect of lithium polysulfides between sulfur cathode and lithium anode is a notorious problem in the commercial application of lithium-sulfur ***,heterostructured TiO_(2)-Fe_(2)TiO_(5)hollow spheres were ... 详细信息

关键词： lithium sulfide (5)

The spectrum and stability of travelling pulses in a coupled FitzHugh-Nagumo equation

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Science China Mathematics 2024年第5期67卷 975-1010页

作者： Qi qiao Xiang zhang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Scientific and Engineering Computing(Ministry of Education) and Shanghai Frontier Science Center of Modern Analysis(CMA-Shanghai)Shanghai Jiao Tong UniversityShanghai 200240China

For a coupled slow-fast FitzHugh-Nagumo(FHN)equation derived from a reaction-diffusionmechanics(RDM)model,Holzer et al.(2013)studied the existence and stability of the travelling pulse,which consists of two fast orbit arcs and two slow ones,where one fast segment passes the unique fold point with algebraic decreasing and two slow ones follow normally hyperbolic critical curve *** and zhang(2021)obtained the existence of the travelling pulse,whose two fast orbit arcs both exponentially decrease,and one of the slow orbit arcs could be normally hyperbolic or not at the ***,we characterize both the nonlinear and spectral stability of this travelling pulse.

关键词： coupled FitzHugh-Nagumo equation singular perturbation travelling pulse spectrum nonlinear stability spectral stability

Enhancing zinc-air battery performance by constructing threedimensional N-doped carbon coating multiple valence Co and MnO heterostructures

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Nano Research 2024年第6期17卷 5104-5113页

作者： Qi Liu Panzhe qiao Miaomiao Tong ying Xie Xinxin zhang Kuo Lin Zhijian Liang Lei Wang Honggang Fu Key Laboratory of Superlight Materials and Surface Technology of the Ministry of Education of the People’s Republic of China Harbin Engineering UniversityHarbin 150080China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of China Heilongjiang UniversityHarbin 150080China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China

Developing highly-efficient bifunctional oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)electrocatalysts is crucial for the widespread application of rechargeable Zn-air batteries(ZABs).Herein,an efficiency electrodeposition and pyrolytic strategy to synthesize the three-dimensional(3D)N-doped carbon coating multiple valence Co and MnO heterostructures supported on carbon cloth substrate(Co-MnO@NC/CC).It contains Co-Co,Co-N,and Co-O bonds,which synergistically enhance the oxygen reaction activity with *** exhibits a working potential of 1.473 V at 10 mA·cm^(−2)for OER and onset potential of 0.97 V for *** calculations demonstrate that the synergy between cobalt and manganese species could optimize the d-band center and reduce the energy barrier of Co-MnO@NC/CC for both OER and ORR ***,the MnO acts as the main OER active site could significantly optimize the energy barrier of O*→OOH*,thus further promoting the OER *** can be directly used as the air-cathode for both liquid-state and solid-state ZABs,which could afford a small voltage gap of 0.75 V at 10 mA·cm^(−2),a high power density of 172.5 mW·cm^(−2)and a long-term durability for 400 h,surpassing those of the Pt/C+RuO_(2)-based ***,the assembled batteries show potential applications in portable devices.

关键词： heterostructure synergy valence cobalt manganese oxide Zn-air battery

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： zhang ying XIAO Gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption