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Journal of Energy Chemistry 2019年第3期28卷 114-120页

作者： jie Xiong Yunjie Huang Jing Li Liying ma Guoxiao Xu Zhao Liu Weiwei Cai Hansong cheng Sustainable Energy Laboratory Faculty of Materials Science and Chemistry China University of Geosciences (Wuhan) College of Chemistry Chemical Engineering and Material Science Zaozhuang University

A facile strategy is introduced to upgrade thermomechanical stability of the cesium pentahydrogen diphosphate(CPD), which is the most efficient inorganic electrolyte among all solid proton conductors,by constructing P–OH···F hydrogen bonds with lanthanum fluoride(LaF_3). The optimal combination of the LaF_3–CPD composite electrolyte is found to be 1:2 in a molar ratio(LaF_3–CPD-2). LaF_3–CPD-2 composite maintains robust solid state, even at a temperature up to 200 °C, which is 50 °C higher than the melting temperature of CPD. Meanwhile, the considerable proton conductivity of CPD is achieved in the LaF_3–CPD-2 composite electrolyte due to the synergistic effect of the P–OH···F hydrogen bonds and the intrinsic proton conductive property of CPD. Last but not least, the LaF_3–CPD-2 composite manifests excellent conductivity durability at 150 °C and low humidity condition with sizeable proton conductivity of0.0262 S cm^(-1) after 60 h operation, implying that the LaF_3–CPD composite could be a promising candidate for intermediate temperature proton conductors.

关键词： Intermediate temperature fuel cell Hydrogen bond Cesium pentahydrogen diphosphate Lanthanum fluoride Thermomechanical stability

Some notes on a conjecture of Zygmund

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Applied mathematics(A Journal of Chinese Universities) 2008年第2期23卷 213-218页

作者： CHEN jie-cheng ZHANG Chun-jie Dept. of math. Zhejiang Univ. Hangzhou 310027 China

In this paper, some classes of differentiation basis are investigated and several positive answers to a conjecture of Zygmund on differentiation of integrals are presented.

关键词： Zygmund's conjecture differentiation of integrals maximal function.

Boundedness of marcinkiewicz integral on Triebel-Lizorkin spaces

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Applied mathematics(A Journal of Chinese Universities) 2010年第1期25卷 48-54页

作者： ZHANG Chun-jie CHEN jie-cheng College of Science Hanzhou Dianzi University Hangzhou 310018 China Department of mathematics Zhejiang University Hangzhou 310027 China

In this paper, we prove the Triebel-Lizorkin boundedness for the marcinkiewicz integral with rough kernel. The method we apply here enables us to consider more general operators.

关键词： marcinkiewicz integral Triebel-Lizorkin spaces rough kernel singular integral.

Preparation of silicon-doped ferrihydrite for adsorption of lead and cadmium:Property and mechanism

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Chinese Chemical Letters 2021年第10期32卷 3169-3174页

作者： Yiran Song Zhuanjun Zhao Jing Li Yang You Xiangbang ma jie Li Xiuwen cheng Key Laboratory of Western China’s Environmental Systems(Ministry of Education)and Key Laboratory for Environmental Pollution Prediction and Control College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

In this study,Si-doped ferrihydrite(Si-Fh) was successfully synthesized by a simple coprecipitation method for removal of heavy metals in ***,the physicochemical properties of Si-Fh before and after adsorption were further studied using several *** Si-Fh exhibited good adsorption capacity for heavy metal ions such as Pb(II) and Cd(II).The maximum adsorption capacities of lead and cadmium are respectively 105.807,37.986 mg/*** distribution coefficients of the materials for Pb(II) and Cd(II) also showed a great affinity(under optimal conditions).Moreover,it was found that the adsorption fit well with the Freundlich isotherm and pseudo-second-order kinetic model which means this was a chemical adsorption *** can be conducted from both characterization and model results that adsorption of Pb(II) and Cd(II) was mainly through the complexation interaction of abundance oxygen functional groups on the surface of ***,the Si-Fh adsorbents with many superiorities have potential for future applications in the removal of Pb(II) and Cd(II) from wastewater.

关键词： Silicon-doped ferrihydrite Water treatment Lead Cadmium Adsorption mechanism

Robust H_∞ control for networked control systems

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Journal of Systems Engineering and Electronics 2008年第5期19卷 1003-1009页

作者： ma Weiguo Shao cheng Inst. of Advanced Control Technology School of Electronic and Information Engineering Dalian Univ. of Technology Dalian 116024 P. R. China

The robust H∞ control for networked control systems with both stochastic network-induced delay and data packet dropout is studied. When data are transmitted over network, the stochastic data packet dropout process can be described by a two-state markov chain. The networked control systems with stochastic network-induced delay and data packet dropout are modeled as a discrete time markov jump linear system with two operation modes. The sufficient condition of robust H∞ control for networked control systems stabilized by state feedback controller is presented in terms of linear matrix inequality. The state feedback controller can be constructed via the solution of a set of linear matrix inequalities. An example is given to verify the effectiveness of the method proposed.

关键词： networked control systems H∞ control markov jump linear systems linear matrix inequality.

Estimating high-spatial resolution surface daily longwave radiation from the instantaneous Global LAnd Surface Satellite(GLASS)longwave radiation product

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International Journal of Digital Earth 2021年第11期14卷 1674-1704页

作者： Qi Zeng jie cheng State Key Laboratory of Remote Sensing Science jointly sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of SciencesBeijingPeople’s Republic of China Institute of Remote Sensing Science and Engineering Faculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China

In this paper,time extension methods,originally designed for clear-sky land surface conditions,are used to estimate high-spatial resolution surface daily longwave(LW)radiation from the instantaneous Global LAnd Surface Satellite(GLASS)longwave radiation *** performance of four time methods were first tested by using ground based flux measurements that were collected from 141 global *** with the accuracy of daily LW radiation estimated from the instantaneous GLASS LW radiation,the linear sine interpolation method performs better than the other methods and was employed to estimate the daily LW radiation as follows:The bias/Root Mean Square Error(RMSE)of the linear sine interpolation method were−6.30/15.10 W/m^(2)for the daily longwave upward radiation(LWUP),−1.65/27.63 W/m2 for the daily longwave downward radiation(LWDN),and 4.69/26.42 W/m^(2)for the daily net longwave radiation(LWNR).We found that the lengths of the diurnal cycle of LW radiation are longer than the durations between sunrise and sunset and we proposed increasing the day length by 1.5 *** accuracies of daily LW radiation were improved after adjusting the day *** bias/RMSE were−4.15/13.74 W/m2 for the daily LWUP,−1.3/27.52 W/m^(2)for the daily LWDN,and 2.85/25.91 W/m^(2)for the daily *** are producing long-term surface daily LW radiation values from the GLASS LW radiation product.

关键词： Surface longwave radiation surface longwave net radiation GLASS time extension method surface radiation budget

Study on dynamic stiffness of supporting structure and its influence on vibration of rotors

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Chinese Journal of Aeronautics 2022年第11期35卷 252-263页

作者： Yongfeng WANG Yanhong ma jie HONG School of Energyand Power Engineering Beihang UniversityBeijing 100083China Research Institute of Aero-Engine Beijing 100083China

The dynamic response of the rotor depends on not only itself but also the dynamical characteristics of the structures that support it. In this paper, the coupling vibration characteristics of the rotor and supporting structure are studied using one simple rotor-supports model firstly, and then the dynamic stiffness of the typical supporting structure of an aero-engine is investigated in use of both numerical and experimental methods. While, one simulation strategy is developed to include dynamic stiffness of realistic supports in the dynamical analysis of the rotor system. The simulated and tested results show that the dynamic stiffness of the supporting structure not only depends on the structural parameters but also is related to the frequency of the excitation force. The dynamic stiffness is affected by the damping and inertia effect when the excitation frequency is high and closed to the resonance frequency of the support, which may decrease the dynamic stiffness *** resonance frequencies may be induced and the critical speed could be reduced or *** higher vibration response peak and overload of the bearing may also be caused by the varied dynamic stiffness, which needs to be avoided in the design of the rotor-supports system.

关键词： Coupling vibration Critical speed Dynamic stiffness Rotor dynamic Rotor-supports system

magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

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Nano Research 2024年第7期17卷 6630-6637页

作者： Ke Liu Zhi Qin jie Shen Zhi cheng Shiyue You Liang ma Jing Zhou Wen Chen State Key Laboratory of Advanced Technology for materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis

Determination of neutron-skin thickness using configurational information entropy

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Nuclear Science and Techniques 2022年第1期33卷 60-66页

作者： Chun-Wang ma Yi-Pu Liu Hui-Ling Wei jie Pu Kai-Xuan cheng Yu-Ting Wang School of Physics Henan Normal UniversityXinxiang 453007China Key Laboratory Optoelectronic Sensing Integrated Application of Henan Province Henan Normal UniversityXinxiang 453007China

Configurational information entropy(CIE)theory was employed to determine the neutron-skin thickness of neutron-rich calcium *** nuclear density distributions and fragment cross sections in 350 MeV/u ^(40-60)Ca+^(9)Be projectile fragmentation reactions were calculated using a modified statistical abrasion-ablation *** quantities were determined from the nuclear density,isotopic,mass,and charge *** linear correlations between the CIE determined using the isotopic,mass,and charge distributions and the neutron-skin thickness of the projectile nucleus show that CIE provides new methods to extract the neutron-skin thickness of neutron-rich nuclei.

关键词： Neutron-skin thickness Configurational information entropy Cross section distribution Projectile fragmentation

Estimating global land surface broadband thermal-infrared emissivityusing advanced very high resolution radiometer optical data

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International Journal of Digital Earth 2013年第S1期6卷 34-49页

作者： jie cheng Shunlin Liang State Key Laboratory of Remote Sensing Science College of Global Change and Earth System ScienceBeijing Normal UniversityBeijingChina Department of Geographical Science University of MarylandCollege ParkMDUSA

An algorithm for retrieving global eight-day 5 km broadband emissivity (BBE)from advanced very high resolution radiometer (AVHRR) visible and nearinfrared data from 1981 through 1999 was presented. Land surface was dividedinto three types according to its normalized difference vegetation index (NDVI)values: bare soil, vegetated area, and transition zone. For each type, BBE at813.5 mm was formulated as a nonlinear function of AVHRR reflectance forChannels 1 and 2. Given difficulties in validating coarse emissivity products withground measurements, the algorithm was cross-validated by comparing retrievedBBE with BBE derived through different methods. Retrieved BBE was initiallycompared with BBE derived from moderate-resolution imaging spectroradiometer (MODIS) albedos. Respective absolute bias and root-mean-square errorwere less than 0.003 and 0.014 for bare soil, less than 0.002 and 0.011 fortransition zones, and 0.002 and 0.005 for vegetated areas. Retrieved BBE wasalso compared with BBE obtained through the NDVI threshold method. Theproposed algorithm was better than the NDVI threshold method, particularly forbare soil. Finally, retrieved BBE and BBE derived from MODIS data wereconsistent, as were the two BBE values.

关键词： earth observation broadband emissivity global land surface satellite soil taxonomy advanced very high resolution radiometer moderate-resolution imaging spectroradiometer