检索结果-内蒙古大学图书馆

IEEE International Conference on Plasma science (ICOPS)

作者： J. Hu H. Geng D. Guo Z. Gu F. Yang M. Sun J. Chen J. Li R. Cheng Science and Technology on Vacuum Technology and Physics Laboratory lanzhou Institute of Physics Lanzhou China

ISBN: (数字)9798350360912

ISBN: (纸本)9798350360929

Ion thruster have been widely used in attitude and orbit control missions because of its outstanding advantages of high specific impulse and long life. A 10 cm diameter Kaufman xenon ion thruster named LIPS-100 ion thruster is under development at Lanzhou Institute of physics (LIP) to provide drag-free control of the gravity gradient satellite and high-resolution observation satellites in super low orbit. The LIPS -100 ion thruster has been applied in satellite and it takes innovations in design, materials compared to those conventional ion thrusters in LIP. The molybdenum material concave ion accelerator grids□hollow cathode of lanthanum hexaboride emitter with emission current 3A and divergent field discharge chamber based on solenoid electromagnet is applied in the LIPS -100 ion thruster. Based on it, the wide range and fine adjustment of plasma density in discharge chamber is realized by using the multi-factor coupling regulation scheme of the anode current□the magnet current and the propellant flow rate of the anode. The test results showed that the LIPS - 100 ion thruster can realize continuous variable-thrust within the range of $1 \mathrm{mN} \square 25 \mathrm{mN}$ over the input power range of $100 \square 720 \mathrm{~W}$, specific impulse varies $175 \square 3500 \mathrm{~s}$, and the thrust resolutions accuracy is better than $25 \mu \mathrm{N}$. This paper will present design status of LIPS-100 ion thruster and discuss the life and reliability with respect to known plasma sputtering failure mechanisms.

关键词： Technological innovation Satellites Attitude control Lips Xenon Ions Orbits

来源：评论

学校读者我要写书评

暂无评论

A study of the influence of different grid structures on plasma characteristics in the discharge chamber of an ion thruster

引用

Plasma science and technology 2023年第1期25卷 147-156页

作者：孙明明龙建飞郭伟龙刘超赵勇 Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou 730000People's Republic of China Gravitational Wave Universe Taiji Laboratory Hangzhou Institute for Advanced StudyUCASHangzhou 310024People's Republic of China Key Laboratory of Gravitational Wave Precision Measurement of Zhejiang Province UCASHangzhou 310024People's Republic of China

The grid structure has significant effects on the discharge characteristics of an ion *** discharge performances of a 30 cm diameter ion thruster with flat,convex and concave grids are *** analysis results show that the discharge chamber with a convex grid has a larger’magnetic-field free area’than the others,and the parallelism of the magnetic-field isopotential lines and anode is generally the same in the three *** densities of the three structures at the grid outlet are in the range of 3.1×1016-6.9×*** the thruster axis direction,the electron temperature in the chamber with the convex and concave grids is in the range of 3.3-3.5 eV,while that with a flat grid is lower,in the range of 3.1-3.5 *** addition,the convex and the concave grids have better uniform distribution of electron ***,the collision frequency ratios show that the axial degree of ionization of the three models is the highest,and the flat grid has the highest discharge efficiency,followed by the convex grid and the concave grid is the least *** test and simulation results of the 30 cm diameter ion thruster with the convex grid show that the measurement and calculation results are 3.67 A and 3.44 A,respectively,and the error above mainly comes from the ignorance of the doubly charged ions and parameter settings in the *** comparison error between the simulation and measurement of beam current density is mainly caused by the actual thermal deformation of the grids during the discharge process,which leads to the change in electric potential distribution and variation of the focusing characteristics of the *** consideration of discharge performance and the thermal grid gap variation,it can be concluded that the flat and concave grids are more suitable for small-diameter ion thrusters,while the convex grid is a more reasonable choice for the higher-power and larger-diameter thrusters.

关键词： ion thruster the grids discharge characteristics

来源：评论

学校读者我要写书评

暂无评论

Quantum Tunneling Enhanced Hydrogen Desorption from Graphene Surface: Atomic versus Molecular Mechanism

引用

Chinese physics Letters 2024年第8期41卷 58-68页

作者： Yangwu Tong Yong Yang Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

We study the desorption mechanism of hydrogen isotopes from graphene surface using first-principles calculations,with focus on the effects of quantum *** low temperatures,quantum tunneling plays a dominant role in the desorption process of both hydrogen monomers and *** the case of dimer desorption,two types of mechanisms,namely the traditional one-step desorption in the form of molecules(molecular mechanism),and the two-step desorption in the form of individual atoms(atomic mechanism),are studied and *** the ortho-dimers,the dominant desorption mechanism is found to switch from the molecular mechanism to the atomic mechanism above a critical temperature,which is∼300K and 200K for H and D,respectively.

关键词： desorption quantum mechanism

来源：评论

学校读者我要写书评

暂无评论

Scale-independent model based on fractal theory for calculating the adhesion force between a particle and rough surfaces

引用

Physical Review E 2024年第3期110卷 034802页

作者： Xiao Wang Weidong Wang Yingmin Zhu Ji Zhang Haiyan Zhang School of Mechano-Electronic Engineering Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou 730000 People's Republic of China

The elimination of the scale-dependent statistical parameters is a challenge in the estimation of the van der Waals force between a particle and rough surfaces. Herein, a scale-independent parameter, the fractal dimension, was introduced into the Rabinovich model to calculate the microadhesion force. First, a Weierstrass-Mandelbrot function is proposed to generate a random 2D contour, which has a simplified form and is more reasonable for spectrum analysis. And then, the roughness scale extraction method was employed to calculate the fractal-dimension value of the real aluminum (Al) surface. And last, the proposed scale-independent Rabinovich-Fractal model was used to calculate the adhesion forces, which are consistent with the results of the atomic force microscopy adhesion test. Aside from providing a more accurate estimation of the van der Waals forces, the proposed model is not influenced by the sampling scale of the surface roughness measurement, which eliminates the related error in van der Waals force estimation.

关键词： Adhesion Roughness Surface & interfacial phenomena

来源：评论

学校读者我要写书评

暂无评论

Room temperature self-healing liquid metals:capabilities,applications and challenges

引用

International Journal of Smart and Nano Materials 2024年第3期15卷 469-501页

作者： Chen Hua Jianye Gao Jing Liu Key Lab of Cryogenic Science and Technology Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina School of Future Technology University of Chinese Academy of SciencesBeijingChina School of Biomedical Engineering Tsinghua UniversityBeijingChina

Self-healing materials span diverse application fields,including flexible electronics,soft robotics,and energy ***,conventional self-healing materials pose a challenge in achiev-ing the delicate balance between flexibility and electrical ***,they also suffer from prolonged healing times,incomplete healing,and high manufacturing *** metals possess excellent self-healing capabilities owing to their unique combination of fluidic and metallic properties,high surface tension,and reversible solid-liquid phase change at room temperature,offering an intriguing material option for addressing the challenges associated with flexibility and elec-trical *** this review article,we comprehensively examine the domain of self-healing liquid metals from the standpoint of typical mechanisms underlying self-healing pro-cesses,as well as practical strategies employed for achieving such ***,we explore representative applications that showcase the potential of these materials while aiming to provide a valuable reference for advancing and enhancing the field of self-healing *** pro-spect along this direction is made.

关键词： Self-healing Liquid metal Smart materials

来源：评论

学校读者我要写书评

暂无评论

Controlling release and cytotoxicity with berberine-loaded KIT-6

引用

Materials Research Innovations 2024年第7期28卷 528-540页

作者： Kumari, Sushma Ahuja, Munish Duhan, Surender Drug Delivery System Lab Department of Physics Deenbandhu Chhotu Ram University of Science and Technology Murthal Haryana Sonipat India Drug Delivery Research Laboratory Department of Pharmaceutical Sciences Guru Jambheshwar University of Science and Technology Haryana Hisar India

In the present investigation, we employed the hydrothermal approach for crafting mesoporous KIT-6 scaffolds and the post-impregnation technique for incorporating the drug. The concentration of berberine within the mesoporous channels of KIT-6 was assessed through UV–visible spectrophotometer. The results showed that the drug molecules were well integrated into the structure of KIT-6, displaying the material’s 3D cubic mesoporous shape and its notable specific surface area of 1376 m2/g. The in vitro drug release profile was investigated in phosphate-buffered saline (pH = 6.8), and the findings point to the possibility of controlling the drug release quantity by loading the drug into the carrier. Using Vero cell lines, the toxicity of the drug-free and drug-loaded samples was examined and it was concluded that by adding berberine to the mesoporous matrix, the drug’s toxicity was dramatically lowered. © 2024 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Controlled drug delivery

来源：评论

学校读者我要写书评

暂无评论

Coherent Population Trapped Spectrum Based on Chip-Scale External Cavity Diode Laser 37

Coherent Population Trapped Spectrum Based on Chip-Scale Ext...

引用

37th European Frequency and Time Forum, EFTF 2024

作者： Zhao, Tian Lian, Jiqing Wu, Senliang Miao, Jie Chen, Zhendong Yang, Ruoao Pan, Duo Chen, Jingbiao School of Electronics Peking University Beijing China School of Mechano-Electronic Engineering Xidian University Xi'an China Lanzhou Institute of Physics Science and Technology on Vacuum Technology and Physics Laboratory China Hefei National Laboratory Heifei230088 China

ISBN: (纸本)9798350354270

This article reports a scheme for obtaining coherent population trapping (CPT) spectrum based on a chip-scale external cavity diode laser (CECDL). The CPT spectrum linewidth is 680Hz. Compared to the scheme using vertical cavity surface emitting laser (VCSEL), CECDL has a comparable small volume and higher laser power of 14mW and narrower linewidth of 270kHz. This is beneficial for improving the frequency stability performance of CPT chip-scale atomic clocks. © 2024 IEEE.

关键词： Frequency stability

来源：评论

学校读者我要写书评

暂无评论

Thick Electrodes of a Self-Assembled MXene Hydrogel Composite for High-Rate Energy Storage

引用

Energy & Environmental Materials 2024年第4期7卷 255-261页

作者： Leiqiang Qin Jianxia Jiang Lintao Hou Fengling Zhang Johanna Rosen Department of Physics Chemistry and Biology(IFM)LinkEoping UniversityLinkEoping SE-58183Sweden Flexible Electronics Innovation Institute(FEII) Jiangxi Key Laboratory of Flexible ElectronicsJiangxi Science and Technology Normal UniversityNanchang 330013China Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials Physics DepartmentJinan UniversityGuangzhou 510632China

Supercapacitors based on two-dimensional MXene(Ti_(3)C_(2)T_(z))have shown extraordinary performance in ultrathin electrodes with low mass loading,but usually there is a significant reduction in high-rate performance as the thickness increases,caused by increasing ion diffusion *** limitations include restacking of the nanosheets,which makes it challenging to realize the full potential of these electrode ***,we demonstrate the design of a vertically aligned MXene hydrogel composite,achieved by thermal-assisted self-assembled gelation,for high-rate energy *** highly interconnected MXene network in the hydrogel architecture provides very good electron transport properties,and its vertical ion channel structure facilitates rapid ion *** resulting hydrogel electrode show excellent performance in both aqueous and organic electrolytes with respect to high capacitance,stability,and high-rate capability for up to 300μm thick electrodes,which represents a significant step toward practical applications.

关键词： energy storage high-rate hydrogel MXene self-assemble

来源：评论

学校读者我要写书评

暂无评论

Plasma–wave interaction in helicon plasmas near the lower hybrid frequency

引用

Chinese physics B 2022年第7期31卷 413-419页

作者： Yide Zhao Jinwei Bai Yong Cao Siyu Wu Eduardo Ahedo Mario Merino Bin Tian Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou 730000China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China Equipo de Propulsi´on Espacial y Plasmas(EP2) Universidad Carlos III de Madrid28911 Legan´esSpain

We study the characteristics of plasma–wave interaction in helicon plasmas near the lower hybrid ***(0D)dispersion relation is derived to analyze the properties of the wave propagation and a 1D cylindrical plasma–wave interaction model is established to investigate the power deposition and to implement the parametric *** is concluded that the lower hybrid resonance is the main mechanism of the power deposition in helicon plasmas when the RF frequency is near the lower hybrid frequency and the power deposition mainly concentrates on a very thin layer near the ***,it causes that the plasma resistance has a large local peak near the lower hybrid frequency and the variation of the plasma density and the parallel wavenumber lead to the frequency shifting of the local *** is found that the magnetic field is still proportional to the plasma density for the local maximum plasma resistance and the slope changes due to the transition.

关键词： helicon plasmas lower hybrid frequency power deposition

来源：评论

学校读者我要写书评

暂无评论

Effects of vibration conditions,spatial confinement and friction on mixing and segregation characteristics of mixed pebble beds for CFETR WCCB blanket

引用

Particuology 2024年第2期85卷 268-279页

作者： Yong Liu Chongyang He Cong Wang Lei Chen Songlin Liu Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230027China Chengdu University Chengdu610106China Zhejiang Lab Hangzhou310000China

This paper presents the study of the dynamic characteristics of confined mixed pebble beds with different friction under different vibration conditions using the discrete element ***λsegre-gation index is used to quantify the degree of particle mixing or *** percolation,convection and diffusion mechanisms are responsible for the segregation patterns of the mixed *** results show the degree of segregation can be suppressed by decreasing the vibration acceleration or free space height below a *** simulation reveals the threshold of vibration acceleration or free space height both are related to the bed height increment which determines the strength of the percolation *** addition,the strength of percolation and convection becomes weaker by decreasing the friction of particles and walls,which makes the pebbled bed remains in a mixed state under *** findings are significant to clarify the main factors behind the three segregation mechanisms and hence provide solutions to retaining the mixed state of the Li2TiO3&Be12Ti mixed pebble bed.

关键词： Vibration Segregation Binary pebble bed Discrete element method

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：