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Spectral Properties and Solubilization Location of 2′-Ethylhexyl 4-（N,N-Dimethylamino）benzoate in Micelles

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Chinese Journal of Chemical Physics 2008年第2期21卷 163-168页

作者： ning Ding Xin-zhen Du Chun Wang Xiao-quan Lu College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

Dual fluorescence and UV absorption of 2′-ethylhexyl 4-（N,N-dimethylamino）benzoate （EHDMAB） were investigated in cationic, non-ionic and anionic micelles. When EHDMAB was solubilized in different micelles, the UV absorption of EHDMAB was enhanced. Twisted intramolecular charge transfer （TICT） emission with longer wavelength was observed in ionic micelles, whereas TICT emission with shorter wavelength was obtained in non-ionic micelles. In particular, dual fluorescence of EHDMAB was significantly quenched by the positively charged pyridinium ions arranged in the Stern layer of cationic micelles. UV radiation absorbed mainly decays via TICT emission and radiationless deactivation. The dimethylamino group of EHDMAB experiences different polar environments in ionic and non-ionic micelles according to the polarity dependence of TICT emission of EHDMAB in organic solvents. In terms of the molecular structures and sizes of EHDMAB and surfactants, each individual EHDMAB molecule should be buried in micelles with its dimethylamino group toward the polar head groups of different micelles and with its 2′-ethylhexyl chain toward the hydrophobic micellar core. Dynamic fluorescence quenching measurements of EHDMAB provide further support for the location of EHDMAB in different micelles.

关键词： Dual fluorescence Twisted intramolecular charge transfer UV absorption Surfactant 2′-Ethylhexyl 4-(N N-dimethylamino)benzoate Sunscreen

Managing economic and social profit of cooperative models in three-echelon reverse supply chain for waste electrical and electronic equipment

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Frontiers of Environmental Science & Engineering 2017年第5期11卷 125-134页

作者： Jian Li zhen Wang Bao jiang College of Economics Ocean University of China Qingdao 266100 China Marine Development Studies Institute Ocean University of China Qingdao 266100 China

In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment （WEEE）. The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In acldition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain fbr WEEE.

关键词： Waste electrical and electronic equipment(WEEE)Reverse supply chains Recycle quantitySocial benefit Cooperative models Duopolistic retailers

Component fault diagnosis for nonlinear systems

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Journal of Systems Engineering and Electronics 2016年第6期27卷 1283-1290页

作者： Junjie Huang zhen jiang Junwei Zhao School of Mechanical and Power Engineering Henan Polytechnic University School of Mechatronics Engineering and Automation Shanghai University

In the field of fault diagnosis, the state equation of nonlinear system, including the actuator and the component, has been established. When the faults in the system appear, it is difficult to observe the fault isolation between the actuator and the component. In order to diagnose the component fault in the nonlinear systems, a novel strategy is proposed. The nonlinear state equation with only the component system is built on mathematical equations. The nonlinearity of the component equation is expanded and estimated with Taylor series. If the actuator is perfect, the anomaly of the state equations reflects the component fault. The fault feature index is defined to detect the component fault and the initial fault. The numerical examples of the component faults are simulated for multiple-input multiple-output(MIMO)nonlinear systems. The results show that the component faults,as well as the incipient faults, can be detected. Furthermore, the effectiveness of the proposed strategy is verified. This method can also provide a foundation for the component fault reconfiguration control.

关键词： multiple-input multiple-output(MIMO) nonlinear systems component faults fault feature index fault diagnosis

Theoretical and numerical study of hydraulic characteristics of orifice energy dissipator

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Water Science and Engineering 2010年第2期3卷 190-199页

作者： ning HE zhen-xing ZHAO Institute of High Energy Physics CAS Beijing 100049 R R. China College of Mechanics and Materials Hohai University Nanjing 210098 P. R. China

Different factors affecting the efficiency of the orifice energy dissipator were investigated based on a series of theoretical analyses and numerical simulations. The main factors investigated by dimension analysis were identified, including the Reynolds number （Re）, the ratio of the orifice diameter to the inner diameter of the pipe （ did ）, and the ratio of distances between orifices to the inner diameter of the pipe （ LID ）. Then, numerical simulations were conducted with a k-ε two-equation turbulence model. The calculation results show the following： Hydraulic characteristics change dramatically as flow passes through the orifice, with abruptly increasing velocity and turbulent energy, and decreasing pressure. The turbulent energy appears to be low in the middle and high near the pipe wall. For the energy dissipation setup with only one orifice, when Re is smaller than 105, the orifice energy dissipation coefficient K increases rapidly with the increase of Re. When Re is larger than l05, K gradually stabilizes. As diD increases, K and the length of the recirculation region L1 show similar variation patterns, which inversely vary with diD. The function curves can be approximated as straight lines. For the energy dissipation model with two orifices, because of different incoming flows at different orifices, the energy dissipation coefficient of the second orifice （K2） is smaller than that of the first. If LID is less than 5, the K value of the LID model, depending on the variation of/（2, increases with the spacing between two orifices L, and an orifice cannot fulfill its energy dissipation function. If LID is greater than 5, K2 tends to be steady; thus, the K value of the LID model gradually stabilizes. Then, the flow fully develops, and L has almost no impact on the value of K.

关键词： orifice energy dissipator theoretical analysis numerical simulation k-ε two-equation turbulent model hydraulic characteristics

Ultrahigh power factors in P-type 1T-ZrX_2(X=S, Se)single layers

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Science Bulletin 2017年第22期62卷 1530-1537页

作者： Ying-Xiang zhen Ming Yang Hang Zhang Guang-Sheng Fu jiang-Long Wang Shu-Fang Wang Rui-ning Wang Hebei Key Laboratory of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei University Institute of Engineering Thermophysics Chinese Academy of Sciences

The thermoelectric performances of 1 T-ZrX_2(X=S and Se) single layers were investigated using a combination of density functional calculations and semi-classical Boltzmann transport theory. Because of the high hole mobilities at 300 K, ultrahigh power factors(PF = S^2σ) were found in the P-type compounds;these values were ~ 11.95 and ~13.58 mWK ~2 m^1 for 1T-ZrS_2 and 1T-ZrSe_2 single layers, ***, because of the Lorenz relation between the electrical conductivity(σ) and an electron's thermal conductivity(K_(el)) given by the Wiedemann-Franz law, the electronic figures of merit(Z_(el)T = PF T/K_(el)) at 300 K were approximately 0.67 and 0.75 for the N-and P-type 1T-ZrSe_2, respectively. In addition, the lattice thermal conductivities(K_(Ph)) were calculated, giving values of ~1.43 and ~0.97 W K ~1 m^1 for 1T-ZrS_2 and 1T-ZrSe_2 single layers, respectively. Therefore, because of the lower K_(Ph)/K_(el) ratio, the P-type 1T-ZrX_2 single layers possess higher fngure-of-merits(ZT = Z_(el)T/(1+(K_(Ph)/K_(el))) than their counterparts. This signifies that the P-type samples demonstrate better thermoelectric performance than the N-type ones. The thermoelectric properties of metastable 2H-ZrX_2(X = S and Se) single layers were also investigated.

关键词： Thermoelectric property Zirconium dichalcogenides Density functional theory Boltzmann-transport theory

A Feedback Correction De-noising Algorithm Based on the Wavelet Coefficients

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Chinese Journal of Electronics 2014年第3期23卷 516-520页

作者： LI ning CAO zhen DENG Zhongliang School of Electronic Engineering Beijing University of Posts and Telecommunications

The localization of satellite interference sources under the condition of low SNR has been a hot research topic at current, where the signal de-noising is important in the following positioning work. With the help of the wavelet analysis theory, this paper proposes a denoising algorithm based on the wavelet coefficients in low SNR. After correcting and reconstructing the signal by the correction coefficients, we could obtain the SNR and Root mean square error(RMSE), and then we could correct the signal for the second time. The simulation results show that this de-noising algorithm can effectively remove the noise of the signal in low SNR, which would have a good effect on the estimation of time delay parameter in the localization of satellite interference sources.

关键词： Signal processing Feedback correction algorithm Wavelet coefficients decomposition De-noising Interference sources localization

Minimal Representations of Cuntz Algebras

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Acta Mathematica Sinica,English Series 2020年第7期36卷 749-764页

作者： Ling Juan YE Li ning jiang School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081P.R.China

Suppose that O_n(2 ≤ n ≤∞) is a Cuntz algebra. There exists a number 1 ≤ k(π, Ω) ≤∞such that if the cyclic representations(H, π, Ω) and(H, π, Ω) of the Cuntz algebra O_n are unitary equivalent, k(π, Ω) = k(π, Ω). Applying the number, one can define a minimal representation of O_n and give a sufficient condition of the minimality for a representation of O_n. Moreover, the relations between minimal states and minimal representations of Cuntz algebras and the relations between the minimality and the irreducibility of the representation of O_n are investigated, respectively.

关键词： algebra. O_n representation

Catalytic Oxidation of Cyclohexene with Molecular Oxygen on Hydrotalcite－like Compounds

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Chemical Research in Chinese Universities 1995年第3期11卷 256-258页

作者： Guo, Jun Wang, ning Jiao, Qing-ze jiang, Da-zhen Yang, Guang-hui Min, En-ze JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA EDUC INST JILIN PROV DEPT CHEMCHANGCHUN 130021PEOPLES R CHINA RES INST PETR PROC BEIJING 100083PEOPLES R CHINA

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关键词： Catalytic Oxidation Cyclohexene Molecular oxygen

Integrated Entry Guidance for Reusable Launch Vehicle

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Chinese Journal of Aeronautics 2007年第1期20卷 1-8页

作者： ning Guo-dong ZHANG Shu-guang FANG zhen-ping School of Aeronautical Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 China

A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor, and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty. Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertainties are presented to demonstrate the capacity and reliability of this method.

关键词： guidance trajectory generation entry onboard constraint robustness