检索结果-南通市图书馆

Phase structure evolution and its effect on magnetic and mechanical properties of B-doped Sm2Co17-type magnets with high Fe content

引用

CHINESE PHYSICS B 2024年第9期33卷 582-588页

作者： Li, Yao-Wen Liu, zhuang Wu, Hai-Chen Wang, Fang zhu, chao-qun Tan, Dong-Liang Liu, Yu Yang, Yang Zhang, Ming-Xiao Chen, Ren-Jie Yan, A-Ru Shanxi Normal Univ Key Lab Magnet Mol & Magnet Informat Mat Minist Educ Taiyuan 030032 Peoples R China Shanxi Normal Univ Sch Chem & Mat Sci Taiyuan 030032 Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn CISRI & NIMTE Joint Innovat Ctr Rare Earth Permane Ningbo 315201 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

The unique cellular microstructure of Fe-rich Sm2Co17-type permanent magnets is closely associated with the structure of the solid solution precursor. We investigate the phase structure, magnetic properties, and mechanical behavior of B-doped Sm2Co17-type magnets with high Fe content. The doped B atoms can diffuse into the interstitial vacancy, resulting in lattice expansion and promote the homogenization of the phase organizational structure during the solid solution treatment in theory. However, the resulting second phase plays a dominant role to result in more microtwin structures and highly ordered 2 : 17R phases in the solid solution stage, which inhibits the ordering transformation of 1 : 7H phase during aging and affects the generation of the cellular structure, and to result in a decrease in magnetic properties, yet the interface formed between it and the matrix phase hinders the movement of dislocations and enhances the mechanical properties. Hence, the precipitation of high flexural strain grain boundary phase induced by B element doping is also a new and effective way to improve the flexural strain of Sm2Co17-type magnets. Our study provides a new understanding of the phase structure evolution and its effect on the magnetic and mechanical properties of Sm2Co17-type magnets with high Fe content.

关键词： Sm2Co17-type magnets magnetic and mechanical properties MICROSTRUCTURE

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm_(2)Co_(17)-type magnet

引用

Rare Metals 2024年第4期43卷 1724-1735页

作者： zhuang Liu Hai-Chen Wu chao-Yue Zhang chao-qun zhu Guo-Xin Chen Huan-Ming Lu Ren-Jie Chen Aru Yan CISRI&NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of Sciences Beijing100049China Analytical Center Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China

Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(17)-type magnet,which is a key factor limiting the further improvement of magnetic energy *** this study,we report that nanoscale strip-like ordered micro-domains distributed in1:7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary *** strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering *** solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1:7H(TbCu_(7)-type structure)phase between the separated strip-like ordered *** disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the ***,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is *** boundaries enriched in Cu have already existed in the precursor with long strip-like ordered ***,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm_(2)Co_(17)-type *** results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the key factor improving the distribution of cell boundary phase in Sm_(2)Co_(17)-type magnets.

关键词： Sm_(2)Co_(17) magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

事件驱动的网络化系统最优控制

引用

控制与决策 2014年第5期29卷 802-808页

作者：祝超群郭戈大连海事大学信息科学技术学院辽宁大连116026

针对随机事件驱动的网络化控制系统,研究其中的有限时域和无限时域内最优控制器的设计问题.首先,根据执行器介质访问机制将网络化控制系统建模为具有多个状态的马尔科夫跳变系统;然后,基于动态规划和马尔科夫跳变线性系统理论设计满足... 详细信息

针对随机事件驱动的网络化控制系统,研究其中的有限时域和无限时域内最优控制器的设计问题.首先,根据执行器介质访问机制将网络化控制系统建模为具有多个状态的马尔科夫跳变系统;然后,基于动态规划和马尔科夫跳变线性系统理论设计满足二次型性能指标的最优控制序列,通过求解耦合黎卡提方程的镇定解,给出最优控制律的计算方法,使得网络化控制系统均方指数稳定;最后,通过仿真实验表明了所提出方法的有效性.

关键词：网络化控制系统介质访问约束事件驱动马尔科夫链最优控制

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Freestanding MoSe_(2)nanoflowers for superior Li/Na storage properties

引用

Tungsten 2024年第1期6卷 238-247页

作者： Qiao Cu chao-qun Shang Guo-Fu Zhou Xin Wang Guangdong Provincial Key Laboratory of Optical Information Materials South China Normal UniversityGuangzhou 510006China School of Materials Science and Engineering and Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China International Academy of Optoelectronics at Zhaoqing South China Normal UniversityZhaoqing 526060China

MoSe_(2),with high theoretical specific capacity,has attracted a lot of *** remains an open challenge to effectively suppress the irreversible selenium dissolution and rapid capacity decrease induced by severe volume change during ***,we synthesize MoSe_(2)nanoflowers dispersed on one-dimensional(1D)N-doped carbon nanofibers(MoSe_(2)@NCNFs)for use as a freestanding *** this unique structure,the 1D N-doped carbon nanofibers are found to not only enhance the conductivity but also ensure the structural integrity during the Li^(+)/Na^(+)insertion/destraction *** expected,at 2 A·g^(-1),the specific capacity of the MoSe_(2)@NCNFs is maintained at 180 mAh·g^(-1)after 500 cycles when used in lithium storage ***,in the case of sodium storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capacity of 122mAh·g^(-1)after 500 *** findings suggest that the MoSe_(2)@NCNF electrodes may be a promising candidate for use in reversible Li/Na storage applications.

关键词： Li/Na storage Freestanding electrode MoSe_(2) Electrochemical reaction kinetics Structural integrity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

River width and depth as key factors of diurnal activity energy expenditure allocation for wintering Spot-billed Ducks in the Xin'an River Basin

引用

Avian Research 2024年第1期15卷 116-122页

作者： chao Yu Xuying Lu Deli Sun Mengnan Chu Xueyun Li qun Li College of Life and Environmental Sciences Huangshan UniversityHuangshan245021China Environment Conservation Research Centre of Xin’an River Basin Huangshan UniversityHuangshan 245021China Department of Resources Conservation Southern Anhui National Wildlife Rescue CenterXiuning 245400China

Rivers are important habitats for wintering ***,they are easily influenced by natural and human *** important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal *** compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy ***,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or *** this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March *** allocation of time and energy expenditure for activity in both normal and disturbed environments was *** results showed that foraging accounted for the highest percentage of time and energy ***,foraging decreased in the disturbed environment than that in the normal *** behavior showed the opposite trend,while other behaviors were similar in both *** total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and *** results oppose the compensatory foraging hypothesis in favor of increased *** optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy *** study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental *** these changes can help understand the maximum fitness of wi

关键词： Diurnal behavior activities River factors Time and energy expenditure allocation Wintering Spot-billed Duck Xin’an River Basin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microbial phenolic metabolites 3-(3',4'-dihydroxyphenyl)propanoic acid and 3',4'-dihydroxyphenylacetic acid prevent obesity in mice fed high-fat diet

引用

Food Science and Human Wellness 2024年第1期13卷 327-338页

作者： Wanbing Chen Ruonan Liu Xiaoling zhu qun Lu Hong Yang Rui Liu College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430000China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of educationWuhan 430000China Wuhan Engineering Research Center of Bee Products on Quality and Safety Control Wuhan 430000China Key Laboratory of Urban Agriculture in Central China Ministry of Agriculture and Rural AffairsWuhan 430000China Hubei Provincial Institute for Food Supervision and Test Wuhan 430070China

Obesity is associated with numerous metabolic disorders,and dietary polyphenols have been confirmed to have beneficial effects on the metabolism in ***,the effect of 3-(3’,4’-dihydroxyphenyl)propanoic acid(DHPA)and 3’,4’-dihydroxyphenylacetic acid(DHAA),two main metabolites of dietary polyphenols,on obesity remains poorly *** this study,DHPA and DHAA were found to alleviate obesity,as well as regulate insulin resistance,lipid metabolism,and oxidative stress response in high-fat diet(HFD)***,the 16S rRNA sequencing and UHPLC-Q-TOF/MS demonstrated that DHPA and DHAA only slightly disturbed the intestinal microbiome,but significantly altered the urine metabolome of HFD mice mainly by regulating pentose and glucuronate interconversion,tyrosine metabolism,pentose phosphate and tricarboxylic acid(TCA)cycle as indicated by metabolic pathway analysis based on Kyoto Encyclopedia of Genes and Genomes(KEGG)*** analysis revealed that the differential metabolites are strongly associated with body weight,blood glucose,insulin level,and superoxide dismutase(SOD)enzyme *** results revealed that DHPA and DHAA exert their anti-obesity effect by regulating important metabolites in the glucose,lipid and tyrosine metabolism pathways.

关键词： Obesity Dietary polyphenol metabolites Gut microbiota Metabonomics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

引用

Nano Research 2024年第6期17卷 4825-4833页

作者： Kai-Kai Niu chao-qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng Yu Ling-Bao Xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transparent cap adjusted the stent placed for stenosis after endoscopic injection of esophageal varices:A case report

引用

World Journal of Clinical Cases 2024年第15期12卷 2614-2620页

作者： Fu-Long Zhang Jing Xu Yuan-Dong zhu Qian-Neng Wu Yan Shi Lei Fang Dan Zhou Hai Wang chao-JunHuang Chun-Hua Zhou qun zhu Department of Gastroenterology Hangzhou Xixi hospitalHangzhou 310023Zhejiang ProvinceChina Department of Hepatopathy Hangzhou Xixi hospitalHangzhou 310023Zhejiang ProvinceChina

BACKGROUND The stent embedded in the esophageal mucosa is one of the complications after stenting for esophageal *** present a case of stent adjustment with the aid of a transparent cap after endoscopic injection of an esophageal varices *** SUMMARY A 61-year-old male patient came to the hospital with discomfort of the chest after the stent implanted for the stenosis because of endoscopic injection of esophageal *** gastroscopy was performed,and the stent embedded into the esophageal *** first,we pulled the recycling line for shrinking the stent,however,the mucosa could not be removed from the *** a forceps was performed to remove the mucosa in the stent,nevertheless,the bleeding form the mucosa was *** then,we used a transparent cap to scrape the mucosa along the stent,and the mucosa were removed successfully without *** A transparent cap helps gastroscopy to remove the mucosa embedded in the stent after endoscopic injection of the esophageal varices stent.

关键词： Stent Transparent cap Stenosis Endoscopic injection Esophageal varices Case report

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Manipulating the Macroscopic and Microscopic Morphology of Large-Area Gravure-Printed ZnO Films for High-Performance Flexible Organic Solar Cells

引用

Energy & Environmental Materials 2024年第2期7卷 233-243页

作者： Zhenguo Wang Jingbo Guo Yaqin Pan Jin Fang chao Gong Lixin Mo qun Luo Jian Lin Changqi Ma School of Nano-Tech and Nano-Bionics University of Science and Technology of China i-Lab & Printable Electronics Research Center Suzhou Institute of NanoTech and Nano-Bionics Chinese Academy of Sciences (CAS) Beijing Engineering Research Center of Printed Electronics Beijing Institute of Graphic Communication Jiangxi Institute of Nanotechnology Chinese Academy of Sciences (CAS)

Gravure printing is a promising large-scale fabrication method for flexible organic solar cells（FOSCs） because it is compatible with two-dimension patternable roll-to-roll fabrication. However, the unsuitable rheological property of Zn O nanoinks resulted in unevenness and looseness of the gravure-printed Zn O interfacial layer. Here we propose a strategy to manipulate the macroscopic and microscopic of the gravure-printed Zn O films through using mixed solvent and poly（vinylpyrrolidone）(PVP) *** regulation of drying speed effectively manipulates the droplets fusion and leveling process and eliminates the printing ribbing structure in the macroscopic morphology. The additive of PVP effectively regulates the rheological property and improves the microscopic compactness of the *** this method, large-area Zn O:PVP films（28 × 9 cm2） with excellent uniformity, compactness, conductivity, and bending durability were fabricated. The power conversion efficiencies of FOSCs with gravure-printed Ag NWs and Zn O:PVP films reached 14.34% and 17.07% for the 1 cm2PM6:Y6 and PM6:L8-BO flexible devices. The efficiency of 17.07% is the highest value to date for the 1 cm2FOSCs. The use of mixed solvent and PVP addition also significantly enlarged the printing window of Zn O ink, ensuring high-quality printed thin films with thicknesses varying from 30 to 100 nm.

关键词： flexible organic solar cell gravure printing large-area flexible interfacial layer rheology properties zinc oxide

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets

引用

Journal of Iron and Steel Research International 2024年第4期31卷 797-809页

作者： Jian Pan Chen-mei Tang Cong-cong Yang De-qing zhu Zheng-qi Guo Wei-qun Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Exploration and Development of Geology and Mineral Resources Co. Ltd.Nanchang 330030JiangxiChina

The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al_(2)O level of 2 wt.%,including reduction index(RI),low-temperature reduction disintegration index(RDI),reduction swelling index(RSI),and high-temperature softening-dripping *** mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and *** the results,the alumina occurrence form presents tremendous impacts on the metallurgical perfor-mance of both magnetite and hematite *** of all alumina occurrence forms contributes to inferior reducibility of pellets,especially in the case of gibbsite for magnetite pellets with a RI of 58.4%and kaolinite for hematite pellets with a RI of 56.8%.However,addition of all alumina occurrence forms improves the RDI of magnetite pellets,while there is no significant difference among various alumina occurrence *** contrast,alumina occurrence forms have little influence on the RDI of hematite *** presence of free alumina,gibbsite,and kaolinite tends to improve the RSI of hematite and magnetite pellets,whereas hercynite gives the opposite trend with a RSI of 25.6%.For softening-dripping performance of magnetite pellets,all alumina occurrence forms contribute to narrower softening-melting ***,alumina,gibbsite,and kaolinite give narrower softening-dripping interval,at 229,217,and 88℃,respectively,whereas addition of hercynite results in the largest melting range at 276℃ due to its high melting *** hematite pellets,free alumina,gibbsite,and hercynite tend to enlarge melting range,whereas kaolinite contributes to lower dripping temperature of 1148℃ and narrow softening-dripping interval of 88℃ due to the formation of a greater amount of slag phase at high temperatures.

关键词： Oxidized pellet Magnetite Hematite Alumina occurrence form Metallurgical performance Blast furnace

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：