检索结果-南通市图书馆

同方期刊数据库

Ceria supported platinum catalyst for CO oxidation reaction:Importance of metallic active species——Commemorating the 100th anniversary of the birth of Academician Guangxian Xu

在线全文

学校读者我要写书评

暂无评论

Journal of rare Earths 2021年第5期39卷 495-503页

作者： Luozhen Jiang Xin Tao li'na li Wen Xia rui Si Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China Division of China TILON Group Technology LimitedShanghai 200090China

Ceria supported platinum catalyst has now been widely studied due to its excellent activity for CO oxidatio ***,the electron state of active metal center is still an open *** this work,a ce ria nanorod support was prepared and platinum(Pt)with 0.9 at%was deposited using an impregnation method to obtain Pt/CeO_(2)*** the help of"light-off"experiment and temperatureprogrammed reduction under CO(CO-TPr)test,the conclusion is proposed that the process of hydrogen reduction can enhance the activity of CO oxidation reaction for the generation of optimal active Pt *** innovative near-situ X-ray absorption fine structure(XAFS)technique was used to investigate the chemical state of central Pt atom during the reaction process,clearly demonstrating that the high oxidized state of Pt does harm to the activity for CO oxidation while the relatively reductive Pt exhibits high activity,and the different oxidized state and chemical environment of Pt during every process has been ***,the activity of our Pt/CeO_(2)catalyst is superior to that of most of the previous reports about CO catalytic oxidation by Pt based ***,the optimal active species(Pt-O_(4))have been identified after hydrogen reduction,which could be a possible key strategy to control the oxidation of Pt.

关键词： Platinum catalyst Ceria support CO oxidation Structure-activity relationship X-ray absorption fine structure rare earths

Wastewater treatment meets artificial photosynthesis:Solar to green fuel production,water remediation and carbon emission reduction

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2022年第4期16卷 157-160页

作者： Zhida li Lu Lu State Key Laboratory of Urban Water resource and Environment School of Civil and Environmental EngineeringHarbin Institute of TechnologyShenzhen 518055China

Current wastewater treatment(WWT)is energy-intensive and leads to vast CO_(2) *** pledge of“double carbon”target encourages a paradigm shift from fossil fiiels use to renewable energy harvesting during *** this context,hybrid microbial photoelectrochemical(MPEC)system integrating microbial electrochemical WWT with artificial photosynthesis(APS)emerges as a promising approach to tackle water-energy-carbon challenges ***,we emphasized the significance to implement energy recovery during WWT for achieving the carbon neutrality ***,we elucidated the working principle of MPEC and its advantages compared with conventional APS,and discussed its potential in fulfilling energy self-sustaining WWT,carbon capture and solar fuel ***,we provided a strategy to judge the carbon profit by analysis of energy and carbon fluxes in a MPEC using several common organics in ***,MPEC provides an alternative of WWT approach to assist carbon-neutral goal,and simultaneously achieves solar harvesting,conversion and storage.

关键词： Wastewater treatment Artificial photosynthesis Microbial photoelectrochemical(MPEC)system Carbon neutral renewable energy

Ultrawide-band radar imagery from multiple incoherent frequency subband measurements

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2011年第3期22卷 398-404页

作者： Xiaojian Xu Jia li School of Electronic and Information Engineering Beihang UniversityBeijing 100191P.R.China Department of Electrical Computer and Systems EngineeringRensselaer Polytechnic InstituteTroy NY12180USA

The problem of combined radar imagery from multiple sparse frequency subbands initially incoherent to each other is of practical importance for radar target discrimination.A new coherent processing technique based on probability density analysis of the subband data is proposed,which is applicable for radar imaging from measurements of two or more initially incoherent radar *** coherence parameters for both amplitude and phase are obtained by combining modern spectral analysis with probability density *** major advantage of the proposed technique lies in that it enables much more robust cohering for the sparse subband data of real-world complex targets.

关键词： radar imagery coherent processing subband spectral analysis.

Sub-Nanometer Displacement Sensor Based on Coupling of Balanced Loss and Gain Cavities

在线全文

学校读者我要写书评

暂无评论

Photonic Sensors 2019年第3期9卷 259-267页

作者： Yuntuan FANG Xiaoxue li School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang 212013 China

Sub-nanometer displacement measurement is still a challenge in the current sensor field. In this study, a new type of displacement sensor is designed which is based on the coupling effect of two balanced gain and loss resonators. The optical properties of the sensor have been studied through the coupled mode theory and scatter matrix. The pole effect in the coupling system can be used to measure the subanometer displacement. The resolution of the sensor can reach 0.001 nm over a dynamic range of 20 nm. The sensor has the highest sensitivity within the range of one *** environmental disturbance and structure parameter perturbation have been demonstrated to make trivial effect on the sensor performance.

关键词： Displacement sensor PT-symmetry pole

A new solver for granular avalanche simulation： Indoor experiment verification and field scale case study

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

Science China(Physics,Mechanics & Astronomy) 2017年第12期60卷 45-55页

作者： Xiaoliang Wang JiaChun li Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China School of Engineering Science University of Chinese Academy of Sciences Beijing 100049 China

A new solver based on the high-resolution scheme with novel treatments of source terms and interface capture for the Savage-hutter model is developed to simulate granular avalanche flows. The capability to simulate flow spread and deposit processes is verified through indoor experiments of a two-dimensional granular avalanche. Parameter studies show that reduction in bed friction enhances runout efficiency, and that lower earth pressure restraints enlarge the deposit spread. The April 9, 2000,Yigong avalanche in Tibet, China, is simulated as a case study by this new solver. The predicted results, including evolution process, deposit spread, and hazard impacts, generally agree with site observations. It is concluded that the new solver for the Savage-hutter equation provides a comprehensive software platform for granular avalanche simulation at both experimental and field scales. In particular, the solver can be a valuable tool for providing necessary information for hazard forecasts, disaster mitigation, and countermeasure decisions in mountainous areas.

关键词： avalanche landslide WAF TVD

Controlling the luminescence of monolayer MoS2 based on the piezoelectric effect

在线全文

学校读者我要写书评

暂无评论

Nano research 2017年第7期10卷 2527-2534页

作者： lijie li Yan Zhang Multidisciplinary Nanotechnology Centre College of Engineering Swansea University Bay Campus SA 1 8EN UK School of Physical Electronics University of Electronic Science and Technology of China Chengdu 610054 China

We report on manipulating the stimulated emission of monolayer molybdenum disulfide （MoS2） with the piezoelectric effect. The analysis is based on quantum mechanics. The stimulated emission of this two-dimensional material has been simulated to establish the relation between the total emission rate and the energy of the photon excitation. We demonstrate that the piezoelectric-induced charges enhance the emission rate by changing the carrier concentration. It is found that the emission intensity is proportional to the carrier density in the low-density range, and eventually reaches a steady value in the high-density region. An externally applied mechanical force also leads to a change in the second harmonic generation of the monolayer MoS2.

关键词： piezo-phototronics luminescence MoS2

high-P/T experimental studies and water in the silicate mantle

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

Science China Earth Sciences 2016年第4期59卷 683-695页

作者： YANG XiaoZhi li Yan State Key Laboratory for Mineral Deposits research School of Earth Sciences and Engineering Nanjing University

Water(or h) in the silicate mantle is a key element in influencing Earth's climate, habitability, geochemical evolution, geophysical properties and geodynamical processes, and has received increasing attention in the past decades. Experimental work under simulated high-pressure and high-temperature conditions is a powerful tool in characterizing the species, distribution, storage capacity and various physicochemical impacts of water in the mantle. In recent years, significant approaches have been acquired about some key physical, chemical and dynamical properties of water in the mantle and their various impacts, as a result of extensive studies by high-pressure and temperature experiments, and our knowledge of Earth's water cycle, especially the deep water cycle, on both temporal and spatial scales has been greatly enhanced. In this paper, a brief review based mainly on experimental studies is presented concerning the current understanding and some recent approaches of water in the silicate mantle, such as the possible origin, amount, storage and the effect on mantle properties.

关键词： high-P/T experiments Silicate mantle Water

Model and Algorithm of Sequence-Based Quantum-Inspired Neural Networks

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2018年第1期27卷 9-18页

作者： li Panchi ZhAO Ya School of Computer and Information Technology Northeast Petroleum University

To enhance the approximation ability of traditional Artificial neural network(ANN), by introducing the quantum rotation gates and the multi-qubits controlled-NOT gates to ANN, we proposed a Sequence input-based quantum-inspired neural network(SIQNN).In our model, the hidden nodes are composed of some multi-qubits controlled-NOT gates, the inputs are described by the multi-dimensional discrete qubits sequences,the output nodes are the traditional neurons. The model parameters include the rotation angles of quantum rotation gates in hide layer and the weights in output *** learning algorithms were derived by employing the Levenberg-Marquardt algorithm. Simulation results of predicting the runoff of the hongjiadu reservoir show that,the SIQNN is obviously superior to the ANN.

关键词： Quantum computation Quantum rotation gate Multi-qubits controlled-NOT gate Quantum inspired neuron Quantum-inspired neural network

Modified precoding strategy over MIMO double-correlated channels

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 35-38页

作者： JIN li-biao li Jian-zeng School of Information Engineering Communication University of China Beijing 100024 China

Double-correlated channels commonly occur due to insufficient scattering around both the transmitting and receiving antennas. In this article, the authors propose a linear precoding strategy with a modified system model over double-correlated channels. In this system model, an inner decorrelation strategy is added combined with precoding. First, a linear precoder that achieves minimum bit error rate （MBEr） is proposed and analyzed based on the modified system model. The simulation results show that the bit error rate （BEr） performance can be improved by decorrelation. Second, the influence of double correlation on multiple input and multiple output （MIMO） capacity is analyzed and simulated.

关键词： MIMO precoding decorrelation capacity