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Method for evaluation of the cleanliness grade of coal resources in the Huainan Coalfield,Anhui,China:a case study

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International Journal of Coal Science & Technology 2021年第4期8卷 534-546页

作者： Guangqing Hu Guijian liu Dun Wu Wenyong Zhang biao Fu School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026AnhuiChina Green Mining Engineering Technology Research Center of Anhui Province Exploration Research InstituteAnhui Provincial Bureau of Coal GeologyHefei 230088AnhuiChina

Based on analysis of a large data set and supplementary sampling and analysis for hazardous trace elements in coal samples from the Huainan Coalfield,a generalized contrast-weighted scale index method was used to establish a model to evaluate the grade of coal cleanliness and its regional distribution in the main coal seam(No.13-1)The results showed that:(1)The contents of Cr,Mn and Ni in the coal seam are relatively high and the average values are greater than 20μg/*** contents of Se and Hg are at a high level while most other trace elements are at normal levels.(2)The cleanliness grade of the coal seam is mainly grade III-IV,which corresponds to a relatively good-medium coal cleanliness ***,some parts of the seam are at grade V(relatively poor coal cleanliness).(3)Coal of relatively good cleanliness grade(grade III)is distributed mainly in the regions corresponding to the Zhuji-Dingji-Gubei coal mines and in the eastern periphery of the Panji coal *** of medium cleanliness(grade IV)is distributed mainly in the regions of the Panji-Xiejiaji and Kouzidong *** poor grade coal(grade V)is distributed in the southwest regions of the coalfield and the contents of Cr,As and Hg in coal collected from the relatively poor coal cleanliness regions often exceed the regulatory standards for the maximum concentration limits.

关键词： Coal cleanliness Hazardous trace elements Evaluation method Huainan coalfield

Multiphonon-resonance quantum Rabi model and adiabatic passage in a cavity-optomechanical system

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Frontiers of physics 2022年第1期17卷 79-87页

作者： Zhi-Rong Zhong Lei Chen Jian-Qi sheng Li-Tuo Shen Shi-biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou350108China

In this paper,we propose a scheme to achieve a multiphonon-resonance quantum Rabi model and adiabatic passage in a strong-coupling cavity optomechanical *** the scheme,when the driving bichromatic laser beam is adjusted to the off-resonant j-order red-and blue-sideband,the interaction between the cavity and mechanical oscillator leads to a j-phonon resonance quantum Rabi ***,we show that there exists a resonant multi-phonon coupling via intermediate states connected by counter-rotating processes when the frequency of the simulated bosonic mode is near a fraction of the transition frequency of the simulated two-level *** a typical example,we theoretically analyze the two-phonon resonance quantum Rabi model,and derive an effective Hamiltonian of the six-phonon ***,we present a method of six-phonon generation based on adiabatic passage across the *** simulations confirm the validity of the proposed ***,the proposed scheme can be extended to the realization of 3j-phonon state.

关键词： quantum Rabi model cavity-optomechanical system adiabatic passage

Tomato yellow leaf curl virus infection of tomato does not affect the performance of the Q and ZHJ2 biotypes of the viral vector Bemisia tabaci

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Insect Science 2011年第1期18卷 40-49页

作者： Meng Li Jian liu Shu-sheng liu Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences Zhejiang UniversityHangzhou China

To better understand the etiology of begomovirus epidemics in regions under invasion we need to know how indigenous and invasive whitefly vectors respond to virus infection. We investigated both direct and indirect effects of infection with Tomato yellow leaf curl virus （TYLCV） on the performance of the invasive Q biotype and the indigenous Asian ZHJ2 biotype of whitefly Bemisia tabaci. The Q biotype performed better than the ZHJ2 biotype on either uninfected or virus-infected tomato plants. However, virus-infection of host plants did not, or only marginally affected, the performance of either biotype of whiteflies in terms of fecundity, longevity, survival, development and population increase. Likewise, association of the vectors with TYLCV did not affect fecundity and longevity of the Q or ZHJ2 biotypes on cotton, a non-host of TYLCV. These results indicate that the alien Q biotype whitefly, but not the indigenous ZHJ2 biotype, is likely to become the major vector of TYLCV in the field and facilitate virus epidemics.

关键词： Bemisia tabaci performance tomato Tomato yellow leaf curl virus virusinfection

Experimental Investigation on the Effect of Blending Ethanol on Combustion Characteristic and Idle Performance in a Gasoline Rotary Engine

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Journal of Thermal Science 2021年第4期30卷 1187-1198页

作者： PAN Jianfeng CHENG biao TAO Jiayu FAN Baowei liu Yangxian OTCHERE Peter 212013

Rotary engine is an ideal electric vehicle range ***,the combustion chamber of rotary engine is very narrow and long at the top dead center,which is detrimental to fuel combustion *** order to improve its economic and emission performance,this paper built an ethanol/gasoline dual-fuel rotary engine test bench,and the combustion and emission performance of gasoline rotary engine under five ethanol blending ratios were *** experimental results showed that,when the fuel pulse width is not adjusted,since the calorific value of ethanol is lower than that of gasoline and the latent heat of vaporization of ethanol is higher than that of gasoline,the addition of ethanol in gasoline lowers the peak *** the ethanol blending ratio reaches 30 vol%,the pressure curve shows a distinct double *** the theoretical air-fuel ratio condition,mixing ethanol in gasoline increases the heat release rate,shortens the combustion duration while prolonging delay *** blending ethanol,HC,CO and NO_(x)emissions have been reduced under various operating *** ethanol blending ratio increases NO_(x)emissions and increases cycle variation *** the ethanol blending ratio is 15 vol%,it has better power ability while maintaining low cycle variation coefficient and emissions.

关键词： rotary engine ethanol emissions idle performance

Understanding the hydroxyl adsorption behavior at Pt electrode surface in high-temperature alkaline solutions

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Chinese Journal of Chemical Engineering 2023年第2期54卷 173-179页

作者： Bo Pan biao liu Shaona Wang Yeqing Lv Hao Du Yi Zhang National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China

Since the application in fuel cell,the electrochemical adsorption of hydroxyl has received considerable attention in recent *** most research mainly focus on the room temperature,in this paper,the electrochemical adsorption of hydroxyl in alkaline solution at high temperature was *** unusual oxidation peak was observed at-0.27 V,suggesting new behavior of hydroxyl adsorption *** is known two kinds of cation hydrated clusters exist in alkaline solution,(H_(2)O)_(x-1)M^(+)-H_(2)O-O_(ad)H and(H_(2)O)_xM^(+)-O_(ad)*** K^(+)and Cs^(+),the cluster shows unstable structure due to the weak interaction between hydrated cation and OH^(-)especially at high ***,For Li^(+),Na^(+)the cluster structure would be stable,as the interaction force between the hydrated cation and OH^(-)is so *** was revealed that the unusual oxidation peak has some relationship with the(H_(2)O)_(x-1)M^(+)-H_(2)O-O_(ad)H cluster(K^(+)and Cs^(+))absorbed at Pt electrode *** the temperature was raised,(H_(2)O)_(x-1)M^(+)-H_(2)O-and-O_(ad)H was disconnected,then the O_(ad)H absorbed at Pt surface got *** on the SEM observation,it was showed the unusual electrochemical oxidation reaction would generate platinum oxides,blocking the reactive sites at Pt electrode surface,thus reducing the electrochemical reactivity of Pt ***,parameters of alkaline concentration and temperature were systematically studied,it was found that increase temperature or alkaline concentration was in favor of the unusual oxidation *** study provides more understanding of hydroxyl adsorption behavior at Pt electrode surface for the high temperature water solution environment.

关键词： Alkaline solution Hydroxyl adsorption Cationic species High temperature Cationic hydrated clusters

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan Hui-yun Hao Qin Wu Yun-qing liu biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Optimal Investment and Excess of Loss Reinsurance with Short-selling Constraint

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 527-534页

作者： sheng liu Jing-xiao Zhang Center for Applied Statistics School of Statistics Renmin University of China Beijing 100872 China

This paper considers the optimal control problem with constraints for an insurance company. The risk process is assumed to be a jump-diffusion process and the risk can be reduced through an excess of loss （XL） reinsurance. In addition, the surplus can be invested in the financial market. In the financial market, the short-selling constraint is one of the main factors which make models more realistic. Our goal is to find the optimal investment-reinsurance policy without short-selling, which maximizes the expected exponential utility of the terminal wealth. By solving the corresponding Hamilton-Jacobi-Bellman equation, the value function and the optimal investment-reinsurance policy are given in a closed form.

关键词： Hamilton-Jacobi-Bellman equation jump-diffusion process short-selling constraint XL reinsurance

Finite element analysis of shape-memory polymer mast

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International Journal of Smart and Nano Materials 2019年第4期10卷 285-299页

作者： Shuai liu Qing-sheng Yang Department of Engineering Mechanics Beijing University of TechnologyBeijingChina

Space masts are widely used in the aerospace engineering as one type of deployable space *** this paper,based on the stimuli-responsive effects of shape-memory polymers(SMPs),an intelligent mast with shape-memory function is *** thermos-mechanical constitutive model of SMPs is associated with the finite element(FE)software,and then the deployable deformation and shape-memory effect of the intelligent mast are investigated by the FE *** is demonstrated that the mast can automatically deploy due to the shape recovery characteristics of ***,the effects of structure parametric of the mast and temperature are also *** results can contribute to the design and application of novel SMP masts.

关键词： Space masts shape-memory polymers FE analysis folding and deployment

Empirical analysis of influence on economic growth of China by income distribution difference

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Journal of Central South University of Technology 2005年第z1期12卷 247-252页

作者： liu Zhen-biao CHEN Xiao-hong School of Business Central South University Changsha 410083 China School of Business Central South University Changsha 410083 China

Based on a theoretic hypothesis that income inequality has both positive and negative effect on economic growth, this paper analyzes the influence of income distribution differences on economic growth of China by establishing a multivariate linear regression model. The influence of income distribution difference on the economic growth of China changes with the change of time. During a short period immediately after China implemented reform and opening up policy, income inequality has a positive influence on the economic growth of China. However, along with the passing of time, such positive influence has become weaker and weaker and even convertes into negative effective. This paper proposes several advices with policy to restrain the difference of income distribution from expanding and weaken its negative effect on economic growth of China.

关键词： income distribution difference positive effect negative effect