检索结果-内蒙古大学图书馆

SSRN 2023年

作者： Fu, Jianghan Jin, Zhao Dai, Zhiwen Su, Guanghui Wang, Chenglong Tian, Wenxi Qiu, Suizheng Department of Nuclear Science and Technology State Key Lab. of Multiphase Flow in Power Engineering Shaanxi Key Lab. of Advanced Nuclear Energy and Technology Xi’an Jiaotong University Xi’an710049 China

Space nuclear reactors possess the inherent benefits of independence from solar energy and the capability to withstand intricate external circumstances. Consequently, the establishment of a dependable automatic control system assumes utmost significance. In this paper, a high-fidelity nonlinear space thermionic nuclear reactor system model is established. An automatic control system with a model predictive control (MPC) controller is designed based on the system. In the case of a nuclear power step response, the MPC controller achieves an overshoot of 0.07% and a settling time of 0.65s. For an electric power step response, the MPC controller yields an overshoot of 0.28% and a settling time of 36.6s. These control performances are better than those achieved by the PID controller. In power tracking control, the MPC controller demonstrates virtually error-free tracking performance. When external reactivity disturbances are introduced, the MPC controller swiftly compensates for the disturbances at the desired level. © 2023, The Authors. All rights reserved.

关键词： Model predictive control

来源：评论

学校读者我要写书评

暂无评论

A MEMS resonator-type viscosity sensor based on triangular cantilever

A MEMS resonator-type viscosity sensor based on triangular c...

引用

2010 International Conference on Mechanic Automation and Control engineering, MACE2010

作者： Zhao, Libo Zhang, Guiming Jiang, Zhuangde Liu, Zhigang State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an China State Key Lab. of Multiple Flow in Power Engineering Xi'an Jiaotong University Xi'an China

ISBN: (纸本)9781424477388

A MEMS (Micro Electro-mechanical System) resonator-type viscosity sensor with range from 0 to 1 mPa·s was presented with good frequency response and high sensitivity. Its sensitive chip with a triangular cantilever structure was investigated. This paper studied the operating principle of the MEMS resonator-type viscosity sensor. The natural frequency of the sensitive chip was deduced with its structure size in theory, which was validated with ANSYS finite element software. The modal analysis and harmonic response analysis for the sensitive chip with triangular cantilever structure were performed to determine the resonant mode of the MEMS viscosity sensor. Finally, the layout and fabrication processes of the sensitive chip of the MEMS resonator-type viscosity sensor were designed and studied. The sensitive chip with small size, high sensitivity and high temperature resistance was fabricated with MEMS technology on SOI (Silicon on Insulator) monocrystalline in order to achieve real-time on-line measurement of fluid viscosity. ©2010 IEEE.

关键词： Natural frequencies

来源：评论

学校读者我要写书评

暂无评论

Effect of Noble Metal in CdS/M/TiO ₂ for Photocatalytic Degradation of Methylene Blue under Visible Light

引用

International Journal of Green Nanotechnology: Materials Science and engineering 2010年第2期1卷 M94-M104页

作者： Shen, Shaohua Guo, Liejin Chen, Xiaobo Ren, Feng Kronawitter, Coleman X. Mao, Samuel S. State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an Shaanxi 710049 China Lawrence Berkeley National Laboratory University of California at Berkeley Berkeley CA 94720 United States

The CdS/M/TiO 2 (M = Ag, Ru, Au, Pd, and Pt) three-component nanojunction systems were constructed using a two-step photodeposition method, and evaluated for their photocatalytic activities through the degradation of ... 详细信息

The CdS/M/TiO ₂ (M = Ag, Ru, Au, Pd, and Pt) three-component nanojunction systems were constructed using a two-step photodeposition method, and evaluated for their photocatalytic activities through the degradation of methylene blue in aqueous solution under visible light irradiation. The authors found that the photocatalytic activity of CdS/M/TiO ₂ (M=Ag, Ru, Au, Pd, Pt) three-component nanojunctions was superior to that of CdS/TiO ₂ two-component system. Moreover, the photocatalytic activity of the three-component nanojunction system was found to be dependent significantly on the type of the noble metals. The results can be explained by the influence of charge transfer on the basis of the work functions of different noble metals. © 2010 Copyright Taylor and Francis Group, LLC.

关键词： CdS/M/TiO 2 heterojunction noble metal photocatalysis Z-scheme

来源：评论

学校读者我要写书评

暂无评论

Regulating Surface Terminals and Interlayer Structure of Ti3c2tx for Superior Nh3 Sensing

SSRN

引用

SSRN 2024年

作者： Li, Jiazheng Li, Yanqiong Zeng, Wen Bai, Bofeng Ren, Shan College of Materials Science and Engineering Chongqing University Chongqing400030 China School of Electronic information & Electrical Engineering Chongqing University of Arts and Sciences Chongqing400030 China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Xi’an710049 China

MXene materials have exhibited potential in electrochemistry, particularly in gas sensing, due to their excellent conductivity, large specific surface area of layered materials, and unique functional groups. However, the gas sensing performance of intrinsic 2D MXene materials is often limited by their fluorine-containing terminals and interfacial structure. In this study, based on intrinsic Ti3C2Tx, we employed alkali treatment and annealing to prepare oxygen-rich Ti3C2(OH)x/Ti3C2Ox with expanded interlayer spacing, achieving enhanced gas sensing performance for NH3. By utilizing the intercalation effect of layered materials and the synergistic effect of regulating MXene unique surface terminations, the sensing materials prepared have achieved optimization of surface chemistry and structural. Compared to intrinsic Ti3C2Tx, the interlayer spacing of oxygen-rich Ti3C2(OH)x/Ti3C2Ox increased from 9.1 Å to 12.1 Å. The surface terminations of oxygen-rich Ti3C2(OH)x/Ti3C2Ox have been defluorinated and oxygenated. The maximum response value of oxygen-rich Ti3C2(OH)x/Ti3C2Ox to NH3 was 35.66, approximately twice that of the original Ti3C2Tx at an NH3 concentration of 200 ppm. DFT (Density functional theory) calculations and DRIFT (In situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy) tests explained the interaction between the surface terminals and NH3, indicating good selectivity and sensitivity of oxygen-rich Ti3C2(OH)x/Ti3C2Ox to NH3. The results of this study demonstrate that the synergistic effects of surface chemistry and structural engineering are crucial for MXene to optimize the electrochemical performance, particularly the gas sensing performance. This provides a feasible approach for the performance optimization of intrinsic MXene materials. © 2024, The Authors. All rights reserved.

关键词： Oxygen

来源：评论

学校读者我要写书评

暂无评论

A MEMS density sensor based on mircro-rectangular cantilever

A MEMS density sensor based on mircro-rectangular cantilever

引用

2010 International Conference on Mechanic Automation and Control engineering, MACE2010

作者： Zhao, Libo Huang, Enze Jiang, Zhuangde Liu, Zhigang State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an China State Key Lab. of Multiple Flow in Power Engineering Xi'an Jiaotong University Xi'an China

ISBN: (纸本)9781424477388

A rectangle cantilever-type micro density sensor was researched based on MEMS (Micro Electro-mechanical System) technology. A Ti-Pt-Au coil and a Wheatstone full bridge were made on the top of the rectangle cantilever-type sensitive chip. The sensitive chip was placed in uniform strong magnetic field. The resonant frequency of the sensitive chip was changed with the change of the AC current's frequency. The resonant frequency of rectangle cantilever could be measured through the Wheatstone full bridge circuit and lock-in amplifier, and then the fluid density associated with the resonant frequency of the sensitive chip could be calculated. The static analysis, modal analysis, a first-order and third-order harmonic response analysis of the rectangle cantilever were performed with ANSYS software. The best locations of the four force-sensitive resistor of Wheatstone bridge were studied. ©2010 IEEE.

关键词： Natural frequencies

来源：评论

学校读者我要写书评

暂无评论

Influence of Bi3+ Doping on the Electrochemical Properties of Ti/Sb-Sno2/Pbo2 Electrode for Zinc Electrowinning

SSRN

引用

SSRN 2024年

作者： Wu, Jia Kang, Xuanqi Xu, Shuangwen Wei, Zhen Xu, Shangyuan Liu, Kang Feng, Qing Jia, Bo Wang, Yunhai Xían Taijin New Energy & Materials Sci-Tech CO. Ltd Xi’an710016 China Department of Environmental Science and Engineering State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiao tong University Xi’an710049 China

Bi3+ doped Ti/Sb-SnO2/PbO2 electrode materials were fabricated by electrodeposition to improve its electrochemical performance in zinc electrowinning. The surface morphology, chemical composition and hydrophilicity of the as-prepared electrodes are characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and contact angle. The electrochemical measurement and the accelerate lifetime experiment are also conduct to investigate the electrocatalytic performance and stability of the electrodes. The results showed that Bi3+ modification electrode has an important effect on the coating morphology, crystal structure, surface hydrophilicity, electrocatalytic activity and stability. The electrode prepared from the solution containing 2 mmol·L-1 Bi(NO3)3 (marked as the Ti/Sb-SnO2/2Bi-PbO2 electrode) exhibits the best hydrophilicity performance (θ=21.6°) and the longest service life (1196 h). During the electrochemical characterization analysis, the Ti/Sb-SnO2/2Bi-PbO2 electrode showed the highest oxygen evolution activity, which can be attributed to the highest electroactive surface (qT*=21.20 C·cm-2) and the best charge transfer efficiency. DFT calculation demonstrate that the doping of Bi lead to the decrease in the OER reaction barrier and increase the DOS of the electrode, which further enhanced the catalytic activity and conductivity of the electrode. Moreover, the simulated zinc electrowinning experiment demonstrate that the Ti/Sb-SnO2/2Bi-PbO2 electrode consume less energy than other electrodes. Therefore, it is expected that the Bi modified electrodes may become a very promising electrode material for zinc electrowinning in the future. © 2024, The Authors. All rights reserved.

关键词： Hydrophilicity

来源：评论

学校读者我要写书评

暂无评论

Nuclear Thermal Coupling Optimization of Baffled Ntp Reactor

SSRN

引用

SSRN 2022年

作者： Duan, Zimian Zhang, Jing Han, Zichao Wang, Mingjun Wu, Yingwei He, Yanan Tian, Wenxi Qiu, Siuzheng Su, Guanghui Shaanxi Key Lab. of Advanced Nuclear Energy and Technology Xi’an Jiaotong University Xi’an710049 China Department of Nuclear Science and Technology State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an710049 China

Nuclear thermal propulsion (NTP) technology has characteristics of high power and high specific impulse. In particular, CERMET fuel reactor has received a lot of research due to its simple form and structure. A general CERMET fuel reactor model is established by using three-dimensional Monte Carlo neutron dynamics program and commercial CFD program Fluent. After nuclear thermal coupling optimization, three partition schemes of baffled reactor were proposed to reduce the temperature difference between the wall and the coolant and lower the relative spike factor in the inner region. A feasible design of redundant control system was then proposed, with a cold clean excess reactivity greater than $3.44 and a minimum dry shutdown reactivity lower than -$5.95, where there was a high control accuracy of 6.7 pcm/mm. The reactor realized safety of the core temperature lower than 3000K under the conditions of total exit temperature of 2650K and thrust of 25000lb. © 2022, The Authors. All rights reserved.

关键词： Cermets

来源：评论

学校读者我要写书评

暂无评论

Correlation Analysis for Online CO 2 Leakage Monitoring in Geological Sequestration

引用

Energy Procedia 2013年 37卷 4374-4382页

作者： Denglong Ma Jianqiang Deng Zaoxiao Zhang State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University No.28 Xianning West Road Xi’an 710049 P.R. China School of Chemical Engineering and Technology Xi’an Jiaotong University No.28 Xianning West Road Xi’an 710049 P.R. China

The paper presents a method for monitoring CO 2 leakage in geological carbon dioxide sequestration. The unsteady state dispersion of leakage CO 2 from geosequestration simulation results showed that the ensemble trend of elevated concentration caused by CO 2 leakage can be viewed as a concentration step change perturbation to the background variation and the initial stage of dispersion process is an increasing variation. The correlation between O 2 and CO 2 variation is well linear if there is no leakage. The external linear perturbation decreases the correlation coefficient. Moreover, too large step change concentration will also reduce the average correlation coefficient. Therefore, online correlation analysis between O 2 and CO 2 in atmosphere is useful to distinguish the leakage CO 2 from complex background variation especially at the beginning of leakage occurring.

关键词： Geosequestration Carbon storage CO 2 leakage monitoring Correaltion analysis

来源：评论

学校读者我要写书评

暂无评论

An LP-DOAS instrument with a laser driven light source for open-path measurement of atmospheric NO2 in Shanghai

An LP-DOAS instrument with a laser driven light source for o...

引用

Progress in Electromagnetic Research Symposium (PIERS)

作者： Mingzhi Li Jun Chen Mingxu Su Huinan Yang Arun Ramachandran Ravi Varma Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering University of Shanghai for Science and Technology Shanghai China Department of Physics National Institute of Technology Calicut Calicut Kerala India

Shanghai is currently faced with the complex atmospheric pollution problem such as ozone (O 3 ) and PM2.5. O 3 is responsible for oxidization of atmospheric constituents that in turn produces secondary pollutants. Reducing atmospheric oxidation is the underpinning strategy for the prevention and control of pollution in this city. According to the observation data from the online automatic monitoring station of Shanghai, the city's O 3 concentration has been rising steadily. In 2013, there are 100 days with ozone as the main pollutants, accounted for 31.9%. By Leighton relationship (K 6 [O 3 ][NO]=K 4 [NO 2 ] = 1), concentration of O 3 is closely related to that of NO 2 . So, continuous monitoring of atmospheric NO 2 has important significance. An instrument was developed for measuring atmospheric NO 2 concentration using a powerful light source in conjunction with the long-path differential optical absorption spectroscopy (LP-DOAS) technique. This system installed at the central section of Shanghai used a laser driven light source (LDLS) and a sensitive TE cooled spectrometer. The LDLS showed better stability, high optical efficiency when compared to traditional arc lamp and light emitting diodes. The light sent into the atmosphere was returned by a retro reflecting mirror placed 1.3km away, and the light returned was sent to a high sensitive TE cooled spectrometer. The spectral range of measurement was 415-455nm and the spectra collected were averaged over 10 min, prior to analyzing for NO 2 concentration. Continuous observations were carried out for two weeks and the NO 2 concentration retrieved ranged from (20-600) ug/m3 with an estimated detection limit of 6.77 ug/m3. The measurement results indicate that it is feasible to use this instrument for detecting the NO 2 with high spatial and temporal sensitivity.

关键词： Absorption Atmospheric measurements Light sources Pollution measurement Optical sensors Wavelength measurement Instruments

来源：评论

学校读者我要写书评

暂无评论

Coupling lattice Boltzmann model for simulation of thermal flows on standard lattices

引用

Physical Review E 2012年第1期85卷 016710-016710页

作者： Q. Li K. H. Luo Y. L. He Y. J. Gao W. Q. Tao Key Laboratory of Thermal Fluid Science and Engineering of MOE National Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Xi’an Shaanxi 710049 China Energy Technology Research Group School of Engineering Sciences University of Southampton Southampton SO17 1BJ United Kingdom Center for Combustion Energy Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal Engineering Tsinghua University Beijing 100084 China Department of Zoology University of Cambridge Cambridge CB2 3EJ United Kingdom

In this paper, a coupling lattice Boltzmann (LB) model for simulating thermal flows on the standard two-dimensional nine-velocity (D2Q9) lattice is developed in the framework of the double-distribution-function (DDF) approach in which the viscous heat dissipation and compression work are considered. In the model, a density distribution function is used to simulate the flow field, while a total energy distribution function is employed to simulate the temperature field. The discrete equilibrium density and total energy distribution functions are obtained from the Hermite expansions of the corresponding continuous equilibrium distribution functions. The pressure given by the equation of state of perfect gases is recovered in the macroscopic momentum and energy equations. The coupling between the momentum and energy transports makes the model applicable for general thermal flows such as non-Boussinesq flows, while the existing DDF LB models on standard lattices are usually limited to Boussinesq flows in which the temperature variation is small. Meanwhile, the simple structure and general features of the DDF LB approach are retained. The model is tested by numerical simulations of thermal Couette flow, attenuation-driven acoustic streaming, and natural convection in a square cavity with small and large temperature differences. The numerical results are found to be in good agreement with the analytical solutions and/or other numerical results reported in the literature.

关键词： LATTICE Boltzmann methods MATHEMATICAL models COMPUTER simulation THERMAL analysis ENERGY dissipation DISTRIBUTION (Probability theory) ACOUSTIC streaming DENSITY functionals

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：