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Defect-manipulated magnetoresistance and above-room-temperature ferromagnetism in two-dimensional BaNi_(2)V_(2)O_(8)

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Chinese Chemical Letters 2024年第3期35卷 523-527页

作者： Pengfei Tan Chuanhui Zhu jinjin Yang Shuang Zhao Tao Xia Mei-Huan Zhao Tao Han Zheng Deng Man-Rong li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhou 510006China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Science Hainan UniversityHaikou 570228China

The intricate correlation between multiple degrees of freedom and physical properties is a fascinating area in solid state chemistry and condensed matter ***,we report a quantum-magnetic system BaNi_(2)V_(2)O_(8)(BNVO),in which the spin correlation was modulated by unusual oxidation state,leading to different magnetic *** BNVO was modified with topochemical reduction(TR)to yield TR-BNVO with partially reduced valance state of Ni^(+)in the two-dimensional NiO_(6)-honeycomb ***,the antiferromagnetic order is suppressed by the introduction of locally interposed Ni^(+)and oxygen vacancies,resulting in a ferromagnetic ground state with the transition temperature up to 710 K.A positive magnetoresistance(7.5%)was observed in the TR-BNVO at 40 K under 7 *** findings show that topological reduction is a powerful approach to engineer low-dimensional materials and accelerate the discovery of new quantum magnetism.

关键词： Layered honeycomb oxide Topochemical reduction Oxygen vacancies Ferromagnetism Magnetoresistance

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仿紧局部紧空间的序列覆盖L-映象

数学进展 2000年第5期29卷 457-463页

作者：李进金漳州师范学院数学系

本文利用特定的覆盖性质，建立了仿紧局部紧空间的序列覆盖Ｌ－映象和紧覆盖Ｌ－映象的特征，得到或深化了局部紧度量空间的一些相应结果．

关键词：序列覆盖映射 L-映射 S-映射 S-映射 CS覆盖 SN覆盖仿紧局部紧空间

Single crystal growth and characterization of 166-type magnetic kagome metals

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CHINESE PHYSICS B 2024年第9期33卷 145-150页

作者： Wu, Huangyu liu, jinjin li, Yongkai Zhu, Peng Yang, liu Chen, Fuhong Hu, Deng Wang, Zhiwei Beijing Inst Technol Ctr Quantum Phys Sch Phys Key Lab Adv Optoelect Quantum Architecture & Measu Beijing 100081 Peoples R China Beijing Inst Technol Beijing Key Lab Nanophoton & Ultrafine Optoelect S Beijing 100081 Peoples R China Yangtze Delta Reg Acad Beijing Inst Technol Mat Sci Ctr Jiaxing 314011 Peoples R China Beijing Inst Technol Zhuhai 519000 Peoples R China

Kagome magnets were predicted to be a good platform to investigate correlated topology band structure, Chern quantum phase, and geometrical frustration due to their unique lattice geometry. Here we reported single crystal growth of 166-type kagome magnetic materials, including HfMn6Sn6, ZrMn6Sn6, GdMn6Sn6 and GdV6Sn6, by using the flux method with Sn as the flux. Among them, HfMn6Sn6 and ZrMn6Sn6 single crystals were grown for the first time. X-ray diffraction measurements reveal that all four samples crystallize in HfFe6Ge6-type hexagonal structure with space group P6/mmm. All samples show metallic behavior from temperature dependence of resistivity measurements, and the dominant carrier is hole, except for GdV6Sn6 which is electron dominated. All samples have magnetic order with different transition temperatures, HfMn6Sn6, ZrMn6Sn6 and GdV6Sn6 are antiferromagnetic with TN of 541 K, 466 K and 4 K respectively, while GdMn6Sn6 is ferrimagnetic with the critical temperature of about 470 K. This study will enrich the research platform of magnetic kagome materials and help explore the novel quantum phenomena in these interesting materials. The dataset of specific crystal structure parameters for HfMn6Sn6 are available in Science Data Bank, with the link https://***/10.57760/sciencedb.j00113.00120.

关键词： kagome metal single crystal growth crystal structure physical property 81.10.-h 71.55.Ak 75.47.-m HFFE6GE6-TYPE GD TM TB

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关于子基的连通性

数学进展 2007年第4期36卷 421-428页

作者：李进金漳州师范学院数学系漳州福建363000

覆盖方法在粗糙集理论研究中的应用越来越受到重视,而其中最重要的两个概念是最近引入的拓扑空间的子集关于子基的内部和闭包.本文研究由它们导出的关于子基的连通性的概念,它比一般拓扑学中的连通性的概念弱,但具有许多类似的性质,这... 详细信息

覆盖方法在粗糙集理论研究中的应用越来越受到重视,而其中最重要的两个概念是最近引入的拓扑空间的子集关于子基的内部和闭包.本文研究由它们导出的关于子基的连通性的概念,它比一般拓扑学中的连通性的概念弱,但具有许多类似的性质,这些性质事实上也是连通性相应结果的推广.

关键词：拓扑子基关于子基的内部关于子基的闭包关于子基的连通性

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天然气净化厂尾气SO_2排放治理工艺探讨

天然气工业 2017年第1期37卷 137-144页

作者：宋彬李金金龙晓达中国石油西南油气田公司天然气研究院

随着国家新《环境保护法》的实施,越来越严格的尾气排放标准给天然气净化厂硫磺回收及尾气处理装置带来巨大的减排压力和技术升级的严峻挑战。为此,分析了国内外天然气净化厂尾气排放标准改进及国内尾气排放现状,对可用于现有装置升级... 详细信息

随着国家新《环境保护法》的实施,越来越严格的尾气排放标准给天然气净化厂硫磺回收及尾气处理装置带来巨大的减排压力和技术升级的严峻挑战。为此,分析了国内外天然气净化厂尾气排放标准改进及国内尾气排放现状,对可用于现有装置升级改造的5种尾气处理工艺(还原吸收法、胺法SO_2吸收法、湿法制酸法、石灰石/石膏湿法和循环流化床干法)、液相氧化还原法和生物脱硫法进行了技术评价分析,并针对2种不同处理规模(原料气潜硫量大于等于1 t/d及原料气潜硫量小于1 t/d)进行了技术经济对比分析。结果表明:①现有天然气净化厂硫磺回收装置排放尾气具有SO_2排放浓度较高、总量小的特点,宜采用还原吸收法、胺法SO_2吸收法和循环流化床法用于尾气治理或采用液相氧化还原法直接处理;②对原料气中潜硫量较大的,尾气处理宜选用还原吸收类工艺,反之则宜采用液相氧化还原法直接处理;③对尾气中潜硫量为中等的,宜选用胺法SO_2吸收工艺,潜硫量较小的则宜选用循环流化床干法工艺。

关键词：天然气净化厂硫磺回收尾气处理处理工艺对比液相氧化还原法生物脱硫 SO_2排放升级改造

Improvement of Ga_(2)O_(3)vertical Schottky barrier diode by constructing NiO/Ga_(2)O_(3)heterojunction

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Journal of Semiconductors 2024年第4期45卷 63-68页

作者： Xueqiang Ji jinjin Wang Song Qi Yijie liang Shengrun Hu Haochen Zheng Sai Zhang Jianying Yue Xiaohui Qi Shan li Zeng liu Lei Shu Weihua Tang Peigang li School of Integrated Circuits&State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China College of Integrated Circuit Science and Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China Beijing Microelectronics Technology Institute Beijing 100076China

The high critical electric field strength of Ga_(2)O_(3)enables higher operating voltages and reduced switching losses in power electronic *** Schottky metals and epitaxial films are essential for further enhancing device *** this work,the fabrication of vertical Ga_(2)O_(3)barrier diodes with three different barrier metals was carried out on an n--Ga_(2)O_(3)homogeneous epitaxial film deposited on an n+-β-Ga_(2)O_(3)substrate by metal-organic chemical vapor deposition,excluding the use of edge *** ideal factor,barrier height,specific on-resistance,and breakdown voltage characteristics of all devices were investigated at room *** addition,the vertical Ga_(2)O_(3)barrier diodes achieve a higher breakdown volt-age and exhibit a reverse leakage as low as 4.82×10^(-8)A/cm^(2)by constructing a NiO/Ga_(2)O_(3)***,Ga_(2)O_(3)power detailed investigations into Schottky barrier metal and NiO/Ga_(2)O_(3)heterojunction of Ga_(2)O_(3)homogeneous epitaxial films are of great research potential in high-efficiency,high-power,and high-reliability applications.

关键词： Ga_(2)O_(3) Schottky barrier diode NiO/Ga_(2)O_(3)heterojunction

DNA Methylation of KLRC1 and KLRC3 in Autoimmune Thyroiditis:Perspective of Different Water Iodine Exposure

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Biomedical and Environmental Sciences 2024年第9期37卷 1044-1055页

作者： Yao Chen jinjin liu Mengying Qu Bingxuan Ren Huaiyong Wu li Zhang Zheng Zhou lixiang liu Hongmei Shen Disorders Control Centre for Endemic Disease ControlChinese Centre for Disease Control and PreventionHarbin Medical UniversityHarbin 150081HeilongjiangChina National Health Commission&Education Bureau of Heilongjiang Province Key Laboratory of Etiology and EpidemiologyHarbin Medical UniversityHarbin 150081HeilongjiangChina Heilongjiang Provincial Key Laboratory of Trace Elements and Human Health Harbin Medical UniversityHarbin 150081HeilongjiangChina Division of Health Risk Factor Monitoring and Control Shanghai Municipal Center for Disease Control and PreventionShanghai 200336China Department of Public Health Administration Affiliated Hospital of Jining Medical UniversityJining 272060ShandongChina Heze Municipal Hospital Shandong Provincial Hospital Heze HospitalHeze 274700ShandongChina

Objective This study aimed to identify differentially methylated genes(DMGs)associated with natural killer cells in patients with autoimmune thyroiditis(AIT),focusing on the influence of varying water iodine exposure *** Participants were divided into categories based on median water iodine(MWI)concentrations:iodine-fortified areas(IFA,MWI300µg/L).A total of 176 matched AIT cases and controls were recruited and divided into 89,40,and 47 pairs for IFA,IAA,and IEA,*** were identified using 850K BeadChip analysis for 10/10 paired *** of DNA methylation and mRNA expression levels of the DMGs was conducted using MethylTarget™and QRT-PCR for 176/176 paired *** KLRC1,KLRC3,and SH2D1B were identified as significant *** revealed that KLRC1 was hypomethylated and highly expressed,whereas KLRC3 was hypermethylated and highly expressed in individuals with ***,KLRC1 was hypomethylated and highly expressed in both IFA and *** The DNA methylation status of KLRC1 and KLRC3 may play crucial roles in AIT ***,DNA methylation of KLRC1 seems to be influenced by different iodine concentrations in water.

关键词： Autoimmune thyroiditis DNA methylation KLRC1 KLRC3 SH2D1B Iodine

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政策主体环境视角下中美页岩气开发比较研究

中国资源综合利用 2024年第1期42卷 77-79页

作者：李岚马瑄李金津刘思源李娟四川长宁天然气开发有限责任公司中国石油西南油气田分公司成都610051

能源安全是国家总体安全的重要组成部分。页岩气是一种非常规天然气资源,美国通过页岩气革命成功实现能源独立。借鉴美国经验,努力促进我国页岩气高效开发成为适应新时代需要的战略选择。本文基于中美两国页岩气开发的现状,从政府政策... 详细信息

能源安全是国家总体安全的重要组成部分。页岩气是一种非常规天然气资源,美国通过页岩气革命成功实现能源独立。借鉴美国经验,努力促进我国页岩气高效开发成为适应新时代需要的战略选择。本文基于中美两国页岩气开发的现状,从政府政策、投资主体与环境保护三个方面进行对比研究,以更好地推进我国页岩气开发。

关键词：中国美国页岩气开发比较

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透平叶片近前缘端壁处换热性能的研究

西安交通大学学报 2017年第7期51卷 44-50页

作者：李劲劲何坤晏鑫李国君西安交通大学能源与动力工程学院西安710049

采用计算流体动力学软件ANSYS CFX11.0、以NASA跨声速透平第一级动叶为研究对象,对带气膜冷却孔的叶栅近前缘端壁区域的流动和换热特性进行了研究,计算获得了3种气膜孔分布条件下,吹风比分别为0.3、0.5、0.7以及孔径分别为1mm、1.5mm时... 详细信息

采用计算流体动力学软件ANSYS CFX11.0、以NASA跨声速透平第一级动叶为研究对象,对带气膜冷却孔的叶栅近前缘端壁区域的流动和换热特性进行了研究,计算获得了3种气膜孔分布条件下,吹风比分别为0.3、0.5、0.7以及孔径分别为1mm、1.5mm时叶栅端壁处的流场结构和斯坦顿数分布。计算结果表明:气膜孔的数目及分布对端壁换热性能和换热均匀性有显著影响,减小孔间距与孔径的比值可以降低前缘端壁的换热系数、提高端壁换热的均匀性;吹风比对冷却流的作用范围和贴壁性有很大影响,所研究的3种吹风比中,吹风比为0.5时壁面换热系数最小,吹风比为0.7时换热系数最大;当吹风比保持0.5不变且气膜孔的直径由1mm增大到1.5mm时,冷却流在端壁上影响的距离增加,相邻冷却流之间区域的换热强度降低。该结果可为透平动叶端壁换热特性的改善和气膜冷却特性的提高提供参考。

关键词：端壁换热气膜冷却