期刊文献+
共找到402篇文章
< 1 2 21 >
每页显示 20 50 100
A Comparative Investigation of Single Crystal and Polycrystalline Ni-Rich NCMs as Cathodes for Lithium-Ion Batteries 被引量:4
1
作者 Xianming Deng Rui Zhang +6 位作者 Kai Zhou Ziyao Gao Wei He Lihan Zhang Cuiping Han Feiyu Kang Baohua Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期1-7,共7页
Nickel-rich LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(NCM,1-x-y≥0.6)is known as a promising cathode material for lithium-ion batteries since its superiority of high voltage and large capacity.However,polycrystalline Ni-rich NCMs... Nickel-rich LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(NCM,1-x-y≥0.6)is known as a promising cathode material for lithium-ion batteries since its superiority of high voltage and large capacity.However,polycrystalline Ni-rich NCMs suffer from poor cycle stability,limiting its further application.Herein,single crystal and polycrystalline LiNi_(0.84)Co_(0.07)Mn_(0.09)O_(2)cathode materials are compared to figure out the relation of the morphology and the electrochemical storage performance.According to the Li^(+)diffusion coefficient,the lower capacity of single crystal samples is mainly ascribed to the limited Li+diffusion in the large bulk.In situ XRD illustrates that the polycrystalline and single crystal NCMs show a virtually identical manner and magnitude in lattice contraction and expansion during cycling.Also,the electrochemically active surface area(ECSA)measurement is employed in lithium-ion battery study for the first time,and these two cathodes show huge discrepancy in the ECSA after the initial cycle.These results suggest that the single crystal sample exhibits reduced cracking,surface side reaction,and Ni/Li mixing but suffers the lower Li^(+)diffusion kinetics.This work offers a view of how the morphology of Ni-rich NCM effects the electrochemical performance,which is instructive for developing a promising strategy to achieve good rate performance and excellent cycling stability. 展开更多
关键词 cathodes electrochemically active surface area Li^(+)diffusion coefficient lithium-ion batteries single crystal
下载PDF
Mitigating kinetic hindrance of single-crystal Ni-rich cathodes through morphology modulation,nickel reduction,and lithium vacancy generation achieved by terbium doping
2
作者 Jiyuan Jian Shuang Lin +13 位作者 Guokang Han Xianglian Zhan Yinghui Shan Rang Xiao Ziwei Liu Dandan Sun Xin Zhang Qingjie Zhou Geping Yin Hua Huo Yulin Ma Pengjian Zuo Xinqun Cheng Chunyu Du 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期566-574,I0012,共10页
Single crystallization has proven to be effective in enhancing the capacity and stability of Ni-rich LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(SNCM)cathode materials,particularly at high cut-off voltages.Nevertheless,the synthesi... Single crystallization has proven to be effective in enhancing the capacity and stability of Ni-rich LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(SNCM)cathode materials,particularly at high cut-off voltages.Nevertheless,the synthesis of high-quality single-crystal particles remains challenging because of severe particle agglomeration and irregular morphologies.Moreover,the limited kinetics of solid-phase Li^(+)diffusion pose a significant concern because of the extended diffusion path in large single-crystal particles.To address these challenges,we developed a Tb-doped single-crystal LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2)(SNCM-Tb)cathode material using a straightforward mixed molten salt sintering process.The Tb-doped Ni-rich single crystals presented a quasi-spherical morphology,which is markedly different from those reported in previous studies.Tb^(4+)oping significantly enhanced the dynamic transport of Li^(+)ions in the layered oxide phase by reducing the Ni valence state and creating Li vacancies.A SNCM-Tb material with 1 at%Tb doping shows a Li^(+)diffusion coefficient up to more than 9 times higher than pristine SNCM in the non-diluted state.In situ X-ray diffraction analysis demonstrated a significantly facilitated H1-H2-H3 phase transition in the SNCM-Tb materials,thereby enhancing their rate capacity and structural stability.SNCM-Tb exhibited a reversible capacity of 186.9 mA h g^(-1)at 5 C,retaining 94.6%capacity after 100 cycles at 0.5 C under a 4,5 V cut-off.Our study elucidates the Tb^(4+)doping mechanisms and proposes a scalable method for enhancing the performance of single-crystal Ni-rich NCM materials. 展开更多
关键词 lithium-ion batteries Ni-rich layered oxides single crystals Tb^(4+) doping Li^(+) diffusion kinetics
下载PDF
Syntheses,challenges and modifications of single-crystal cathodes for lithium-ion battery 被引量:2
3
作者 Xinyue Zhang Yudong Zhang +2 位作者 Jiuding Liu Zhenhua Yan Jun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期217-229,I0004,共14页
Single-crystal cathodes(SCCs)are promising substitute materials for polycrystal cathodes(PCCs)in lithium-ion batteries(LIBs),because of their unique ordered structure,excellent cycling stability and high safety perfor... Single-crystal cathodes(SCCs)are promising substitute materials for polycrystal cathodes(PCCs)in lithium-ion batteries(LIBs),because of their unique ordered structure,excellent cycling stability and high safety performance.Cathode materials with layered(LiCoO_(2),LiNi_xCo_yMnzO_(2),LiNi_xCo_yAl_(2)O_(2))and spinel structure(LiMn_(2)O_(4),LiNi_(0.5)Mn_(1.5)O_(4))show a relatively stable electrochemical performance,but still lack of sufficient attention in research field.In this review,we begin with the definition,structural features and electrochemical advantages of SCCs.Common SCCs synthesis methods and the thermodynamic growth mechanism of SCCs with oriented facet exposure are summarized in the following part.Then we introduce the problems and challenges of SCCs faced and the corresponding modification strategies.Finally,the industrialization progress of SCCs is brifly outlined.We intend to tease out the difficulties and advances of SCCs to provide insights for future development of high-performance SCCs for practical LIBs. 展开更多
关键词 lithium-ion batteries single crystal CATHODE SYNTHESES Modifications
下载PDF
Towards Single-component Molecular Conductor[Ni(dmit)2]by Charge Disproportionation:2[Ni(dmit)2]^0.5→[Ni(dmit)2]+[Ni(dmit)2]^- 被引量:1
4
作者 QiFANG HongLEI WenXU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1109-1112,共4页
A new method of synthesizing single-component molecular conductor [Ni(dmit)2] by the reaction 2(Me4N)[Ni(dmit)2]2 [Ni(dmit)2] + (Me4N)[Ni(dmit)2] is reported. [Ni(dmit)2] exhibits a semiconductive behavior above 167... A new method of synthesizing single-component molecular conductor [Ni(dmit)2] by the reaction 2(Me4N)[Ni(dmit)2]2 [Ni(dmit)2] + (Me4N)[Ni(dmit)2] is reported. [Ni(dmit)2] exhibits a semiconductive behavior above 167 K, while from 167 K down to the measuring limit of 60 K, it exhibits metallic conductivity. 展开更多
关键词 single-component molecular conductors conductivity charge disproportionation.
下载PDF
Research on the Relationship between Density of States and Conducting Properties of Single-walled Carbon Nanotubes 被引量:1
5
作者 ZhenhuaZHANG JingcuiPENG +1 位作者 XiaohuaCHEN JianxiongWANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第2期110-112,共3页
The analytical expression of the electronic density of states (DOS) for single-walled carbon nanotubes (SWNTs) has been derived on the basis of graphene approximation of the energy E(k) near the Fermi level EF. The di... The analytical expression of the electronic density of states (DOS) for single-walled carbon nanotubes (SWNTs) has been derived on the basis of graphene approximation of the energy E(k) near the Fermi level EF. The distinctive properties of the DOS, the normalized differential conductivity and the current us bias for SWNTs are deduced and analyzed theoretically. The singularities in the DOS (or in the normalized differential conductivity) predict that the jump structure of current (or conductance)-bias of SWNTs exists. All conclusions from the theoretical analysis are in well agreement with the experimental results of SWNT's electronic structure and electronic transport. In other words, the simple theoretical model in this paper can be applied to understand a range of spectroscopic and other measurement data related to the DOS of SWNTs. 展开更多
关键词 single-walled carbon nanotubes Graphene approximation of energy Electronic density of states Normalized differential conductivity
下载PDF
Measurement of thermal conductivity of materials using single-side TPS technique
6
作者 SUN Jian-qiang LI Yan-ning 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第3期285-292,共8页
Based on the traditional measurement theory of transient plane source (TPS) technique, single-side TPS method is proposed for measuring the thermal conductivity of single specimen. The problem of transient heat conduc... Based on the traditional measurement theory of transient plane source (TPS) technique, single-side TPS method is proposed for measuring the thermal conductivity of single specimen. The problem of transient heat conduction in a semi-infinite boundary condition is studied and the theoretical formula of single-side TPS method is deduced. During the measurement, the influence of the probe heat capacity on the results is analyzed and the corresponding mathematical compensation model is established, and a series of experiments on different materials are conducted by hot disk probe at normal temperature and pressure. The results show that the relative error with the single-side TPS method is less than 5% and the relative standard deviation is no greater than 3%. This method has high accuracy and good reproducibility, which provides a feasible measuring method for single material that does not meet the requirements of the standard TPS theory. 展开更多
关键词 single-side transient plane source (TPS) method thermal conductivity single material probe heat capacity
下载PDF
Spin-dependent negative differential conductance in transport through single-molecule magnets
7
作者 罗威 王瑞强 +1 位作者 胡梁宾 杨谋 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期399-405,共7页
Transport properties are theoretically studied through an anisotropy single-molecule magnet symmetrically connected to two identical ferromagnetic leads. It is found that even though in parallel configuration of leads... Transport properties are theoretically studied through an anisotropy single-molecule magnet symmetrically connected to two identical ferromagnetic leads. It is found that even though in parallel configuration of leads’ magnetizations, the total current still greatly depends on the spin polarization of leads at certain particular bias region, and thus for large polarization a prominent negative differential conductance (NDC) emerges. This originates from the joint effect of single-direction transitions and spin polarization, which removes the symmetry between spin-up and spin-down transitions. The present mechanism of NDC is remarkably different from the previously reported mechanisms. To clarify the physics of the NDC, we further monitored the shot noise spectroscopy and found that the appearance of the NDC is accompanied by the rapid decrease of Fano factor. 展开更多
关键词 SPINTRONICS single-molecule magnets negative differential conductance shot noise
下载PDF
Influence of chirality on the thermal conductivity of single-walled carbon nanotubes
8
作者 冯雅 祝捷 唐大伟 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期310-316,共7页
The influence of chirality on the thermal conductivity of single-walled carbon nanotubes (SWNTs) is discussed in this paper, using a non-equilibrium molecular dynamics (NEMD) method. The tube lengths of the SWNTs ... The influence of chirality on the thermal conductivity of single-walled carbon nanotubes (SWNTs) is discussed in this paper, using a non-equilibrium molecular dynamics (NEMD) method. The tube lengths of the SWNTs studied here are 20, 50, and 100 nm, respectively, and at each length the relationship between chiral angle and thermal conductivity of a SWNT is revealed. We find that if the tube length is relatively short, the influence of chirality on the thermal conductivity of a SWNT is more obvious and that a SWNT with a larger chiral angle has a greater thermal conductivity. Moreover, the thermal conductivity of a zigzag SWNT is smaller than that of an armchair one. As the tube length becomes longer, the thermal conductivity increases while the influence of chirality on the thermal conductivity decreases. 展开更多
关键词 single-walled carbon nanotube thermal conductivity chiral angle molecular dynamics simulation
下载PDF
On the Thermal Conductivity of Single-Walled Carbon Nanotube Ropes
9
作者 Poonam Silotia Seema Dabas +1 位作者 Aditya Saxena Shri-Prakash Tewari 《Soft Nanoscience Letters》 2013年第1期7-10,共4页
Recently measured thermal conductivity in single-walled carbon nanotube ropes in the temperature range 8 - 350 K has been explained using an anisotropic dynamical model which not only takes into account the quasi two-... Recently measured thermal conductivity in single-walled carbon nanotube ropes in the temperature range 8 - 350 K has been explained using an anisotropic dynamical model which not only takes into account the quasi two-dimensional nature of the folded graphene sheets that forms the nanotubes, but also the intertube coupling, in addition to the phonon frequency and dimensionality dependent relaxation time of phonon-phonon scattering and interaction. 展开更多
关键词 Thermal conductIVITY single-WALLED Carbon NANOTUBE Ropes Phonon-Phonon Scattering and Interaction DYNAMICAL Model
下载PDF
First-principles study of the relationship between the formation of single atom catalysts and lattice thermal conductivity
10
作者 Chaozheng He Pei Shi +3 位作者 Donglin Pang Zhanying Zhang Long Lin Yingchun Ding 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第6期502-506,共5页
Single atom catalysts(SACs)have been in the forefront of catalysts research because of their high efficiency and low cost and provide new ideas for development of renewable energy conversion and storage technologies.H... Single atom catalysts(SACs)have been in the forefront of catalysts research because of their high efficiency and low cost and provide new ideas for development of renewable energy conversion and storage technologies.However,the relationship between the intrinsic properties of materials such as lattice thermal conductivity and catalysis remains to be explored.In this work,the lattice thermal conductivity of BN and graphene was calculated by Sheng BTE.In addition,the adsorption properties of 3d-TM(TM=V,Cr,Mn,Fe,Co,Ni)on BN and graphene were investigated using first-principles methods,and it was found that Ni atom can form relatively stable SACs compared to other TMs.The molecular dynamics(MD)simulation and migration barrier of Ni loaded on BN and graphene were calculated.Our study found that graphene has higher thermal conductivity and is easier to form SACs than BN,but the SACs formed on BN surface have higher thermodynamic stability. 展开更多
关键词 First-principles calculation Thermal conductivity single atom catalysts GRAPHENE BN
原文传递
Choice for graphene as conductive additive for cathode of lithium-ion batteries 被引量:15
11
作者 Ying Shi Lei Wen +2 位作者 Songfeng Pei Minjie Wu Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第3期19-26,共8页
Graphene is a promising conductive additive for the lithium-ion batteries(LIBs) and shows great potential especially with its fast development of the large scale fabrication technology. This work has explored the infl... Graphene is a promising conductive additive for the lithium-ion batteries(LIBs) and shows great potential especially with its fast development of the large scale fabrication technology. This work has explored the influence of the incorporation of graphenes prepared by three typical methods on the electrochemical performance of the LiCoO_2-based cathode focusing on the choice for the effective graphene as conductive additive for the cathode of LIBs. Through the comparison of the intrinsic characteristics of graphenes and the electrochemical performance of electrodes with graphene, it is found that graphene with low disorder degree and large size is not suitable for LiCoO_2 cathodes as conductive additive. Conversely, the graphene with oxygen functional groups, relatively low surface area and proper size displays much better electrochemical performance when it is used as conductive additive. This work also demonstrates the transmission mechanism for different graphenes as conductive additives in the LiCoO_2 materials, and further reveals that the conductivity of graphene is not the only factor as conductive additives, surface chemistry and sheet size of the graphene are also essential factors which greatly influence the electrochemical performance of electrode. In addition, when combined with Super P, only 1% graphene is enough to construct an efficient conductive network in the electrode. This study also gives a new sight on the practical application of graphene as conductive additive for high performance LIBs. 展开更多
关键词 GRAPHENE conductIVE additive lithium-ion batteries LICOO2 CATHODE
下载PDF
Grain size regulation for balancing cycle performance and rate capability of LiNi_(0.9)Co_(0.055)Mn_(0.045)O_(2) single crystal nickel-rich cathode materials 被引量:8
12
作者 Jiapei Wang Xibin Lu +3 位作者 Yingchao Zhang Jiahui Zhou Jiexi Wang Shengming Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第2期681-687,共7页
It is challenging to balance the cyclability and rate capability of single crystal nickel-rich cathode materials(Ni>0.8).Multicomponent oxides by spray pyrolysis shows potential as highly-reactive precursors to syn... It is challenging to balance the cyclability and rate capability of single crystal nickel-rich cathode materials(Ni>0.8).Multicomponent oxides by spray pyrolysis shows potential as highly-reactive precursors to synthesize single crystal nickel-rich cathode at lower temperature,yet Ni^(2+)will severely inhibit particle growth when Ni content exceeds 0.9.Herein,lithium nitrate(LiNO_(3))with low melting point and strong oxidation is introduced as collaborate lithium salts for fabrication of well-dispersed submicron and micron single crystal LiNi_(0.9)Co_(0.055)Mn_(0.045)O_(2)(NCM90)cathode without extra unit operation.By changing amount of LiNO_(3),particle size regulation is realized and cation disorder can be diminished.The as-prepared material with optimal content of 4 wt%LiNO_(3)(NCM90-4 LN)displays the most appropriate particle size(1μm)with approximately stoichiometric structure,and presents better kinetics characterization of lithium-ion diffusion(15%higher than NCM90)and good electrochemical performance with specific discharge capacity of 220.6 and 173.8 mAh g^(-1) at 0.1 C and 10 C at room temperature,respectively.This work broadens the conventional research methodology of size regulation for single crystal Ni-rich cathode materials and is indispensable for the development of designing principal of nickel-rich cathode materials for lithium-ion batteries. 展开更多
关键词 single crystal LiNi_(0.9)Co_(0.055)Mn_(0.045)O_(2) Spray pyrolysis Lithium nitrate lithium-ion batteries
下载PDF
Effect of heat treatment on microstructure and properties of single crystal copper cold-welded joints 被引量:1
13
作者 Huang Yong Ran Xiaolong +1 位作者 Yan Xiaojuan Guo Tingbiao 《China Welding》 EI CAS 2019年第2期1-9,共9页
With the means of electron backscattered diffraction(EBSD),mechanical properties test and digital eddy current metal conductivity,the single crystal copper cold-welded joint was tested and analyzed,the structure chang... With the means of electron backscattered diffraction(EBSD),mechanical properties test and digital eddy current metal conductivity,the single crystal copper cold-welded joint was tested and analyzed,the structure change of cold-welded joint and the effect of heat treating on the structure and property of cold-welded joint were discussed.The results show that:The deformation area of the single crystal copper cold welded joint is broken,the crystalline grain at the interface of the joint is refined,and the single crystal structure is still maintained in the base metal area.The hardness of the deformation area increases greatly,the conductivity of the joint does not change much,and the tensile strength of the joint reaches about 70%of that of the base metal.At the interface of the heat treating joint,the single crystal structure of the deformation area and the base metal area are destroyed,and the grains grow up at the interface and the orientation is different.The hardness of the joint interface is much lower than that of the non-heat treating joint,the electrical conductivity of the joint is good,and the tensile strength of the joint is higher than that of the base metal. 展开更多
关键词 single CRYSTAL copper COLD pressure welding heat treatment conductIVITY
下载PDF
Dielectric spectroscopy studies of ZnO single crystal 被引量:1
14
作者 成鹏飞 李盛涛 王辉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期529-532,共4页
Dielectric relaxation and charge transport induced by electron hopping in ZnO single crystal are measured by using a novocontrol broadband dielectric spectrometer. Typical Debye-like dielectric relaxation originating ... Dielectric relaxation and charge transport induced by electron hopping in ZnO single crystal are measured by using a novocontrol broadband dielectric spectrometer. Typical Debye-like dielectric relaxation originating from electronic hopping between electronic traps and conductive band in surface Schottky barrier region is observed for ZnO single crystal-Au electrode system. However, after insulation of ZnO single crystal by heat treatment in rich oxygen atmosphere, dielectric relaxation and alternating current conductance are observed simultaneously in the dielectric spectra, implying that dielectric relaxation and charge transport can be induced simultaneously by electronic hopping at high temperature in an ordered system. The intrinsic correlation between local dielectric relaxation and long range charge transport offers us a new method to explore complicated dielectrics. 展开更多
关键词 ZnO single crystal electronic hopping conductANCE dielectric relaxation
下载PDF
Temperature dependent phonon modes and ionicity of LiGaO_2 single crystal
15
作者 马继云 方煦 +4 位作者 M. Kamran 赵华英 毕聪志 赵柏儒 邱祥冈 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3313-3317,共5页
This paper reports that polarized far-infrared reflectivity measurements have been done on LiGaO2 single crystal along two crystalline taxes at different temperatures. The temperature dependent frequencies of the long... This paper reports that polarized far-infrared reflectivity measurements have been done on LiGaO2 single crystal along two crystalline taxes at different temperatures. The temperature dependent frequencies of the longitudinal and transverse optical phonon have been obtained from the real part of optical conductivity and the loss function respectively. A small Drude component is observed at frequency below 300 cm^-1 which could arise from Li ions or oxygen deficiencies. The ionicity of LiGaO2 has been studied from the analysis of the Born effective charge of different ions. 展开更多
关键词 INFRARED optical conductivity LiGaO2 single crystal PHONON
下载PDF
Thermal properties of single-walled carbon nanotube crystal 被引量:1
16
作者 胡丽君 刘基 +3 位作者 刘政 邱彩玉 周海青 孙连峰 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期307-311,共5页
In this work, the thermal properties of a single-walled carbon nanotube (SWCNT) crystal are studied. The thermal conductivity of the SWCNT crystal is found to have a linear dependence on temperature in the temperatu... In this work, the thermal properties of a single-walled carbon nanotube (SWCNT) crystal are studied. The thermal conductivity of the SWCNT crystal is found to have a linear dependence on temperature in the temperature range from 1.9 K to 100.0 K. In addition, a peak (658 W/mK) is found at a temperature of about 100.0 K. The thermal conductivity decreases gradually to a value of 480 W/mK and keeps almost a constant in the temperature range from 100.0 K to 300.0 K. Meanwhile, the specific heat shows an obvious linear relationship with temperature in the temperature range from 1.9 K to 300.0 K. We discuss the possible mechanisms for these unique thermal properties of the single-walled carbon nanotube crystal. 展开更多
关键词 single-walled carbon nanotube SWCNT crystal thermal conductivity specific heat
下载PDF
Structural and Thermal Properties of Tb, Ce Doped Y<sub>2.97</sub>Gd<sub>0.03</sub>Al<sub>2</sub>Ga<sub>3</sub>O<sub>12</sub>Single Crystals
17
作者 Mohammad Faheem Kelvin Lynn 《American Journal of Analytical Chemistry》 2014年第11期695-700,共6页
The structural and thermal properties of yttrium-aluminum-gadolinium-gallium (Y2.97Gd0.03Al2Ga3O12) single crystals doped with terbium (0.1%), cerium (0.01%) and co-doped with both terbium and cerium ((0.1, 0.01)%) we... The structural and thermal properties of yttrium-aluminum-gadolinium-gallium (Y2.97Gd0.03Al2Ga3O12) single crystals doped with terbium (0.1%), cerium (0.01%) and co-doped with both terbium and cerium ((0.1, 0.01)%) were investigated. All samples were heated (calcined) at 1400°C for 15 hours before crystallization. X-ray powder diffraction (XRD) patterns of all calcined samples showed the presence of yttrium gallium aluminate (Y3Al2Ga3O12) and gadolinium gallium oxide (Gd3GaO6) while the grown crystals were single phase of Y3Al2Ga3O12. The lattice parameter of the crystals decreased with Ce doping. The thermal conductivity of each sample was determined from 25°C to 300°C and found to decrease exponentially with increasing temperature. All doped crystals have different thermal conductivity, which is attributed to the crucial influence of crystals structures. 0.01% Ce:YAGG was found to be a strong candidate for scintillators and other lasing materials because of its good thermal behavior (10.71 W/m·K). 展开更多
关键词 YAGG single CRYSTALS Lattice Parameters Thermal conductIVITY
下载PDF
基于单孔稀释试验的人工湖渗漏探测方法及应用
18
作者 梁越 赵卓越 +2 位作者 夏日风 张宏杰 代磊 《人民长江》 北大核心 2024年第4期207-213,共7页
渗漏是影响湖库安全的关键因素,对其进行准确、高效探测一直是水工安全领域中的技术难题。与基于电磁理论的地球物理探测技术不同,基于井流理论的单孔稀释技术可以直接得到与渗流场相关的含水层参数且无需额外的参数转换。但传统的单孔... 渗漏是影响湖库安全的关键因素,对其进行准确、高效探测一直是水工安全领域中的技术难题。与基于电磁理论的地球物理探测技术不同,基于井流理论的单孔稀释技术可以直接得到与渗流场相关的含水层参数且无需额外的参数转换。但传统的单孔稀释试验往往仅对点位渗漏性进行定性判断,针对大尺度下渗漏规模的定量分析应用较少。为此,基于单孔稀释测速原理对四川省仁寿县某渗漏人工湖进行研究。在人工湖附近钻孔后进行单孔稀释试验,通过监测NaCl溶液电导率数据得到钻孔流速,通过解译流速数据得到了人工湖最大渗漏通道位于湖体左侧钻孔ZK6~ZK7区域420~440 cm深度范围和ZK8区域300~400 cm深度范围,钻孔剖面渗流量为4.24 cm^(3)/s。现场试验应用表明:单孔稀释法不仅能定性分析出渗漏通道的空间位置,还能定量计算出地下流速、渗流量参数。试验证明单孔稀释渗漏探测原理应用于湖库渗漏探测中具有较好的推广应用价值。 展开更多
关键词 渗漏探测 单孔稀释法 电导率 渗漏通道 渗漏量 人工湖
下载PDF
pH和电导率的在线校准仪
19
作者 陈戈华 姜帅 《长春工业大学学报》 CAS 2024年第4期306-312,共7页
设计了一款应用于电厂水汽系统电导率及pH表检测仪表校准的pH和电导率的在线校准仪。本校准仪采用了计算型pH的检测方法,通过测量电导率间接测量pH值,可避免低电导率水pH测量干扰因素的影响。采用交流电阻箱,用数字电位器的方式实现交... 设计了一款应用于电厂水汽系统电导率及pH表检测仪表校准的pH和电导率的在线校准仪。本校准仪采用了计算型pH的检测方法,通过测量电导率间接测量pH值,可避免低电导率水pH测量干扰因素的影响。采用交流电阻箱,用数字电位器的方式实现交流电阻。通过自行设计数字的交流电阻箱模拟水中的电导率,用来对仪表进行校验。在线校准仪采用电脑端LabVIEW软件作为上位机控制软件,单片机为核心的嵌入式系统,可以实现采集、检测、二次表校准、数据处理和数据存储等功能控制。 展开更多
关键词 电导率 计算型pH 在线校准仪 电阻箱 单片机
下载PDF
“In-N-out” design enabling high-content triethyl phosphate-based non-flammable and high-conductivity electrolytes for lithium-ion batteries 被引量:2
20
作者 Mengchuang Liu Fenfen Ma +8 位作者 Zicheng Ge Ziqi Zeng Qiang Wu Hui Yan Yuanke Wu Sheng Lei Yanli Zhu Shijie Cheng Jia Xie 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第2期724-731,共8页
Safety issues related to flammable electrolytes in lithium-ion batteries(LIBs) remain a major challenge for their extended applications.The use of non-flammable phosphate-based electrolytes has proved the validity in ... Safety issues related to flammable electrolytes in lithium-ion batteries(LIBs) remain a major challenge for their extended applications.The use of non-flammable phosphate-based electrolytes has proved the validity in inhibiting the combustion of LIBs.However,the strong interaction between Li^(+) and phosphate leads to a dominant solid electrolyte interphase(SEI) with limited electronic shielding,resulting in the poor Li^(+) intercalation at the graphite(Gr) anode when using high-phosphate-content electrolytes.To mitigate this issue and improve Li^(+) insertion,we propose an “In-N-Out” strategy to render phosphates “noncoordinative”.By employing a combination of strongly polar solvents for a “block effect” and weakly polar solvents for a “drag effect”,we reduce the Li^(+)–phosphate interaction.As a result,phosphates remain in the electrolyte phase(“In”),minimizing their impact on the incompatibility with the Gr electrode(“Out”).We have developed a non-flammable electrolyte with high triethyl phosphate(TEP) content(>60 wt.%),demonstrating the excellent ion conductivity(5.94 mS cm^(-1) at 30 ℃) and reversible Li^(+) intercalation at a standard concentration(~1 mol L^(-1)).This approach enables the manipulation of multiple electrolyte functions and holds the promise for the development of safe electrochemical energy storage systems using non-flammable electrolytes. 展开更多
关键词 lithium-ion batteries graphite anode high-phosphate-content electrolytes non-flammable electrolyte excellent ion conductivity standard concentration
原文传递
上一页 1 2 21 下一页 到第
使用帮助 返回顶部