检索结果-南通市图书馆

Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo zhang Yuankang Zha Yixing Ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia zhang huajie Yin Tongfei Shi Haimin zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

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

Preparation of a Novel Green Fluorescent Carbon Quantum Dots and Application in Fe^(3+)-Specific Detection in Biological System

引用

Journal of Analysis and Testing 2024年第1期8卷 40-51页

作者： Xianfen zhang Wenxian Wang Lijiao Guan huajie Chen Dai Li Lipeng zhang Saipeng Huang School of Chemical Engineering Northwest UniversityXi'an 710069China Chemical Technology Academy of Shandong Province Qingdao University of Science and TechnologyJinan250014China

Trace ferric ion(Fe^(3+))detection has attracted increasing attention as an essential and indispensable role in many physiological and pathological research.The green-emitting carbon quantum dots(Green-CQDs)were obtained through a green and facile one-step hydrothermal method for the specific recognition and trace detection of Fe^(3+)in this paper.The optimal excitation and emission wavelengths of the CQDs were 395 nm and 490 nm,respectively.The stokes shift was up to 95 nm,which can effectively reduce the background fluorescence interference.In addition,it also exhibited good water solubility,stability,and high biocompatibility.The fluorescence intensity of Green-CQDs was linearly related to the concentration of Fe^(3+)(range of 0-80μmol/L),and the detection limit was as low as 59 nmol/L.These good properties were favorable and successful for Fe^(3+)detection in tap water,human serum samples and living cells.In addition,a fluorescence visual test paper(FP@CQDs)was prepared utilizing filter paper as carrier,which can quickly identify Fe^(3+)in real time,and is suitable for the visualization analysis of Fe^(3+)in environment.As an efficient nanoprobe,the Green-CQDs held great promise and bright prospects in practical application in prevention and early clinical diagnosis of Fe^(3+)-associated diseases.

关键词： Carbon quantum dots Fluorescent Hydrothermal Fe^(3+)-specific detection Cell imaging

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

Comprehensive optimization of piezoelectric coefficient and depolarization temperature in Mn-doped Bi_(0.5)Na_(0.5)TiO_(3)-Bi_(0.5)K_(0.5)TiO_(3)-BaTiO_(3)lead-free piezoceramics

引用

Journal of Materials Science & Technology 2024年第5期172卷 255-263页

作者： Huashan Zheng Enwei Sun huajie Luo Xiaoyu zhang Yixiao Yang Bin Yang Rui zhang Shantao zhang Wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing100083China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania16802United States of America

Lead-free Bi_(_(0.5))Na_(_(0.5))TiO_(3)(BNT)piezoelectric ceramics have the advantages of large coercive fields and high Curie temperatures.But the improvement of piezoelectric coefficient(d 33)is usually accompanied by a huge sacrifice of depolarization temperature(T d).In this work,a well-balanced performance of d 33 and T d is achieved in MnO_(2)-doped 0.79(Bi_(_(0.5))Na_(_(0.5))TiO_(3))-0.14(Bi_(0.5)K_(0.5)TiO_(3))-0.07BaTiO_(3)ternary ceramics.The in-corporation of 0.25 mol%MnO_(2)enhances the d 33 by more than 40%,while T d remains almost unchanged(i.e.,d 33=181 pC/N,T d=184℃).X-ray diffraction(XRD)shows that an appropriate fraction of the small axis-ratio ferroelectric phase(pseudo-cubic,P c)coexists with the long-range ferroelectric phase(tetrag-onal,T)under this MnO_(2)doping.Piezoelectric force microscopy(PFM)has revealed a special domain configuration,namely large striped and layered macro domains embedded with small nanodomains.This study provides a distinctive avenue to design BNT-based piezoelectric ceramics with high piezoelectric performance and temperature stability.

关键词： BNT-BKT-BT ceramics Mn doping Piezoelectric Depolarization temperature Phase structure

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

Biomimetic porous silicon oxycarbide ceramics with improved specific strength and efficient thermal insulation

引用

Journal of Materials Science & Technology 2024年第1期168卷 185-193页

作者： Zhuoqing zhang Jinghan Li Lei Cao Yu Shi huajie Yang Rui Yang Fan Xie Xing zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Shenyang Aircraft Design and Research Institute Shenyang 110035China

Considering the challenge of aerodynamic heating,the development of high-performance insulating ce-ramic materials with lightweight and low thermal conductivity is crucially important for aerospace vehi-cles to achieve flight at high speed for a long time.In this work,macro-porous silicon oxycarbide(SiOC)ceramics with directional pores(DP-SiOC)(mean pore size of 88.1μm)were prepared using polysiloxane precursors via freeze casting and photocrosslinking,followed by pyrolysis.The DP-SiOC samples were lightweight(density∼0.135 g cm^(-3))with a porosity of 90.4%,which showed good shapability through the molding of polysiloxane precursors.The DP-SiOC samples also exhibited an ultra-low thermal con-ductivity of 0.048 W(m K)^(-1)at room temperature,which can also withstand heat treatment at 1200°C for 1 h.In addition,scaffolds with triply periodic minimal surfaces(TPMS)were fabricated using digital light processing(DLP)printing,which was further filled with polysiloxane precursors for increasing the strength of DP-SiOC.The TPMS scaffolds filled with macro-porous SiOC ceramics(TPMS-DP-SiOC)showed good integration between TPMS and macro-pore structures,which had a porosity∼75%and high specific strength of 9.73×10^(3)N m kg^(-1).The thermal conductivity of TPMS-DP-SiOC samples was 0.255 W(m K)^(-1)at room temperature.The biomimetic TPMS-DP-SiOC ceramics developed in this study are likely used for thermal protection systems.

关键词： Thermal insulation Light weight Macro-porous ceramics SiOC

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

Heterointerface engineering of rhombic Rh nanosheets confined on MXene for efficient methanol oxidation

引用

Journal of Energy Chemistry 2024年第6期93卷 419-428,I0011页

作者： Qi zhang Quanguo Jiang Xiang Yang Chi zhang Jian zhang Lu Yang Haiyan He Guobing Ying huajie Huang College of Materials Science and Engineering Hohai UniversityNanjing 210098JiangsuChina New Energy Technology Engineering Lab of Jiangsu Province College of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023JiangsuChina School of Materials Science and Engineering Southeast UniversityNanjing 211100JiangsuChina

Although metallic rhodium(Rh)is regarded as a promising platinum-alternative anode catalyst of direct methanol fuel cell(DMFC),the conventional"particle-to-face"contact model between Rh and matrix largely limits the overall electrocatalytic performance due to their insufficient cooperative effects.Herein,we report a controllable and robust heterointerface engineering strategy for the bottom-up fabrication of rhombic Rh nanosheets in situ confined on Ti_3C_(2)T_x MXene nanolamellas(Rh NS/MXene)via a convenient stereoassembly process.This unique design concept gives the resulting 2D/2D Rh NS/MXene heterostructure intriguing textural features,including large accessible surface areas,strong"face-toface"interfacial interactions,homogeneous Rh nanosheet distribution,ameliorative electronic structure,and high electronic conductivity.As a consequence,the as-prepared Rh NS/MXene nanoarchitectures exhibit exceptional electrocatalytic methanol oxidation properties in terms of a large electrochemically active surface area of 126.2 m~2 g_(Rh)~(-1),a high mass activity of 1056.9 mA mg_(Rh)-~1,and a long service life,which significantly outperform those of conventional particle-shaped Rh catalysts supported by carbon black,carbon nanotubes,reduced graphene oxide,and MXene matrixes as well as the commercial Pt nanoparticle/carbon black and Pd nanoparticle/carbon black catalysts with the same noble metal loading amount.Density functional theory calculations further demonstrate that the direct electronic interaction at the well-contacted 2D/2D heterointerfaces effectively enhances the adsorption energy of Rh nanosheets and induces a left shift of the d-band center,thereby making the Rh NS/MXene configuration suffer less from CO poisoning.This work highlights the importance of rational heterointerface design in the construction of advanced noble metal/MXene electrocatalysts,which may provide new avenues for developing the next-generation DMFC devices.

关键词： Rhodium nanosheet Ti_(3)C_(2)T_(x)MXene Heterointerface Electrocatalyst Fuel cell

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

Repeated Wildfires in the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian Ages) in Northwestern China

引用

Acta Geologica Sinica(English Edition) 2022年第5期96卷 1752-1763页

作者： HOU Haihai SHAO Longyi LIANG Guodong TANG Yue zhang huajie zhang Jiaqiang College of Mining Liaoning Technical UniversityFuxinLiaoning 123000China College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China Oil&Gas Resource Survey Center China Geological SurveyMinistry of Land and ResourceBeijing 100029China

The coal-bearing strata in the southern Junggar Basin in northwestern China have recently attracted the attention of coal geologists. Its abundance of coal resources is of great interest as there is a potential of unlocking details about the palaeoclimatic information. Coal deposits have the capacity to record wildfire events, even those with inefficient combustions. To characterize wildfire events and palaeoclimatic history of the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian ages), 22 coal samples from borehole cores and coal mines in the southern Junggar Basin were collected and their macerals were analyzed. The results indicated that fusinite and semi-fusinite were the dominant components of inertinite with proportions of 35.27% and 54.67%, respectively. The presence of inertinite is an indicator that wildfires occurred at the time of peat land development, and the widespread occurrence suggests large scale wildfires during the Middle Jurassic. This study proposes a new parameter for the evaluation of wildfire features by combining burning frequency and burning temperature. The comprehensive evaluation index(CEI) was influenced by the lacustrine basin level and ancient plant types from a sequence framework. During the Middle Jurassic, most wildfires were surface fires with low level and ground fire with high level. High oxygen levels were estimated in the lower, middle, and upper members of the Xishanyao Formation with corresponding to 26.78%, 24.55%, and 23.55%, respectively. The high oxygen levels would be the primary cause of repeated wildfires in the Middle Jurassic. These results are helpful for understanding palaeoclimatic changes in the Middle Jurassic.

关键词： wildfire charcoal Middle Jurassic comprehensive evaluation index northwestern China

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

Revealing structure correlation between ionic liquid and metal-organic framework matrix

引用

Magnetic Resonance Letters 2024年第2期4卷 65-72页

作者： Ligang Xu Wenda zhang Chenjie Lou Chenxu Geng Yuxiu Sun Jie Liu Yongchao Shi huajie Luo Jipeng Fu Haiyan Zheng Mingxue Tang Center for High Pressure Science and Technology Advanced Research Beijing100193China College of Materials Science and Engineering Guilin University of TechnologyGuilin541004China State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin300387China University of Science and Technology Beijing Beijing100083China Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesChina Jiliang UniversityHangzhou310018China

Solid-state batteries are rising rapidly in response to the fast-increasing energy demand.Metal-organic framework(MOF) loaded with ionic liquids has brought new opportunities for solid-state batteries owing to its good interfacial compatibility and high ionic conductivity. MOF-808 is selected to be filled with Li-contained ionic liquid for structure and ion dynamics investigation using nuclear magnetic resonance(NMR) and X-ray diffraction.This study finds that the introduced ionic liquid would partially soften the matrix of MOF-808 and thus yield amorphous phase. By selective isotope replacement under cycling symmetric ^(6)Li metal cell, Li^(+)ion is observed to mainly go cross ionic liquid in the open channel of matrix under potential polarization.

关键词： Nuclear magnetic resonance Solid-state batteries MOF-808 Ionic liquid Local 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

采用动态相关度权重的特征选择算法

引用

计算机工程与应用 2024年第4期60卷 89-98页

作者：许华杰刘冠霆张品秦远卓广西大学计算机与电子信息学院南宁530004 广西大学广西多媒体通信与网络技术重点实验室南宁530004 北部湾港防城港码头有限公司广西防城港538001 广西大学土木建筑工程学院南宁530004

基于互信息的特征选择算法在考虑候选特征提供的新分类信息时,通常忽略了候选特征的加入会使得已选特征和类标签的相关性发生变化而带来额外的新增信息量,以及在计算冗余信息时采用累加求和的形式可能导致低估候选特征的冗余程度。针对... 详细信息

基于互信息的特征选择算法在考虑候选特征提供的新分类信息时,通常忽略了候选特征的加入会使得已选特征和类标签的相关性发生变化而带来额外的新增信息量,以及在计算冗余信息时采用累加求和的形式可能导致低估候选特征的冗余程度。针对以上问题,提出动态相关度权重的定义,以更全面地考虑候选特征带来的新信息量成分;提出改进冗余项的定义,采用取最大值和归一化策略,以解决传统算法存在的低估冗余问题;在此基础上提出一种采用动态相关度权重的特征选择算法(feature selection using dynamic relevance weight,FSDRW)。选取五种当前主流的基于互信息的过滤式特征选择算法进行对比实验,在来自加州大学尔湾分校UCI和亚利桑那州立大学ASU的机器学习测试数据集上的实验表明,所提出的算法在分类准确率及综合性能方面具有较好的表现。最后将所提出算法应用于广西某水库工程的微震、爆破信号识别中,算法选取出的特征用于微震信号识别可达到98.86%的分类准确率,验证了算法在实际应用中的有效性。

关键词：特征选择互信息信息熵动态相关度权重

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

一种面向多源传感器的飞行器类型识别综合仿真方法

引用

系统仿真学报 2024年第1期36卷 149-159页

作者：顾韶竹应宇欣张华杰童逸琦北京电子工程总体研究所北京100854 北京航空航天大学北京100191 软件开发环境国家重点实验室北京100191

针对现有飞行器类型识别仿真方法主要以单传感器、单目标识别为主,没有考虑真实场景下光电、雷达、电子侦收等多种传感器设备对飞行器参数联合采集的过程,导致仿真场景不丰富、变化不够复杂的问题。构建了面向多源传感器的飞行器综合仿... 详细信息

针对现有飞行器类型识别仿真方法主要以单传感器、单目标识别为主,没有考虑真实场景下光电、雷达、电子侦收等多种传感器设备对飞行器参数联合采集的过程,导致仿真场景不丰富、变化不够复杂的问题。构建了面向多源传感器的飞行器综合仿真平台,包括:光电模拟器,使用循环生成对抗网络生成飞行器红外图像;空情模拟器,采用三自由度飞行方法生成飞行器运动轨迹;雷达模拟器,利用椭球方程模拟目标的雷达轨迹和雷达反射截面积;电抗模拟器,通过典型信号源收集和随机噪声引入来模拟复杂电磁环境。在仿真数据集上的实验结果表明,引入多种传感器信息能有效提升目标类型的识别效果,提升模型辅助决策能力。

关键词：多源传感器飞行器仿真光电模拟器空情模拟器雷达模拟器电抗模拟器

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

论资本逻辑对“气候新陈代谢”的撕裂

引用

福州大学学报（哲学社会科学版） 2024年第3期38卷 10-18,170页

作者：张翔蔡华杰南京大学马克思主义学院江苏南京210023 福建师范大学马克思主义学院福建福州350117

工业革命时期,马克思对受资本主义工业化推动的资本主义农业进行了批判,指明资本主义生产方式不仅扭曲了人与自然的和谐关系,而且与工商业联合起来撕裂了农业生态系统的物质变换,同时这一裂痕随着生态恶化渗透进社会发展的各个领域。进... 详细信息

工业革命时期,马克思对受资本主义工业化推动的资本主义农业进行了批判,指明资本主义生产方式不仅扭曲了人与自然的和谐关系,而且与工商业联合起来撕裂了农业生态系统的物质变换,同时这一裂痕随着生态恶化渗透进社会发展的各个领域。进入21世纪,资本逻辑主导的“新陈代谢断裂”致使全球气候问题逼近临界阈值,不仅使自然界、劳动者彻底沦为资本增殖的异化工具,更通过气候帝国主义加剧了治理领域的不平等。习近平生态文明思想则从生产、治理、合作三重领域突破了资本主义发展模式禁锢的牢笼,强调营造人与自然和谐共生的良好氛围、致力于构建全人类生态命运共同体、最终实现生态的可持续发展。

关键词：资本逻辑新陈代谢断裂全球气候变化习近平生态文明思想

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

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：