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Aerodynamic characteristics of co-flow jet wing with simple high-lift devices

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Chinese Journal of Aeronautics 2022年第10期35卷 67-83页

作者： Zhenhao ZHU Tianhang xiao Haolin ZHI Shuanghou deng Yujin LU College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Numerical investigations are conducted to explore the aerodynamic characteristics of three-dimensional Co-Flow Jet(CFJ) wing with simple high-lift devices during low-speed takeoff and landing. Effects of three crucial parameters of CFJ wing, i.e., angle of attack, jet momentum and swept angle, are comprehensively examined. Additionally, the aerodynamic characteristics of two CFJ configurations, i.e., using open and discrete slots for injection, are compared. The results show that applying CFJ technique to a wing with simple high-lift device is able to generate more lift,reduce drag and enlarge stall margin with lower energy expenditure due to the super-circulation effect. Increasing the jet intensity can reduce the drag significantly, which is mainly contributed by the reaction jet force. The Oswald efficiency factor is, in some circumstances, larger than one,which indicates the potential of CFJ in reducing induced drag. Compared with clean wing configuration, using CFJ technique allows the aerodynamic force variation less sensitive to the swept angle, and such phenomenon is better observed for small swept angle region. Eventually, it is interesting to know that the discrete slotted CFJ configuration demonstrates a promising enhancement in aerodynamic performance in terms of high lift, low drag and efficiency.

关键词： Active flow control Co-flow jet Continuous injection Discrete injection slot Simple high-lift device

Enhancement on parallel unstructured overset grid method for complex aerospace engineering applications

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Chinese Journal of Aeronautics 2023年第1期36卷 115-138页

作者： Tianhang xiao Haolin ZHI Shuanghou deng Zhaolin CHEN Xinying LI College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China China Special Vehicle Research Institute Jingmen 448035China

In the present study,an efficient overset grid method by means of parallel implicit hole-cutting is proposed for the sake of simulating unsteady flows in aerospace engineering involving multiple bodies in relative *** view of the degraded computational efficiency and robustness for conventional overset grid assembly,several innovative techniques are developed within the overset grid assembly process,viz.,a bookkeeping alternative digital tree method to speed up the donor-cell searching,a fast parallel advancing front algorithm to accelerate the wall-distance calculation and a message-passing strategy with efficient information communication and lower storage expenditure within distributed computational *** contribution of the developed techniques is evidenced by comparison with the existing alternative ways in terms of computing ***,the overset grid method is embedded into an inhouse programed URANS solver to examine its capability in predicting the flow field of complex applications such as helicopter,store separation and component *** show that the developed overset grid methodology is,in practice,able to resolve the aerodynamic characteristics of complex aerospace engineering with a high-fidelity flow topology and accuracy.

关键词： Alternative digital tree Implicit hole-cutting Overset grid assembly Parallel computing Wall distance

Spinning microresonator-induced chiral optical transmission

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Frontiers of physics 2023年第1期18卷 175-183页

作者： Lu Bo xiao-Fei Liu chuan Wang Tie-Jun Wang State Key Laboratory of Information Photonics and Optical Communications and School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China School of Artificial Intelligence Beijing Normal UniversityBeijing 100875China

Chiral quantum optics is a new research area in light-matter interaction that depends on the direction of light propagation and offers a new path for the quantum regulation of light-matter *** this paper,we study a spinning Kerr-type microresonator coupled withΛ-type atom ensembles,which are driven in opposite directions to generate asymmetric photon *** find that a photon blockade can only be generated by driving the spinning resonator on right side without driving the spinning microresonator from the left side,resulting in *** coupling strength between system modes can be precisely controlled by adjusting the detuning amount of the atomic pump *** of the splitting of the resonant frequency generated by the Fizeau drag,the destructive quantum interference generated in right side drive prevents the nonresonant transition path of state|1,0⟩to state|2,0⟩.This direction-dependent chiral quantum optics is expected to be applied to chiral optical devices,single-photon sources and nonreciprocal quantum communications.

关键词： chiral quantum optics spinning microresonator nonreciprocal photon blockade

First Enantioselective Synthesis of (2R,3R)-and(2S,3S)-2-(4-hydroxyphenyl)-3-hydroxymethyl-1,4-benzodioxan-6-carbaldehyde

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Chinese Chemical Letters 2001年第3期12卷 189-192页

作者： Wen Xin GU xiao Bi JING xiao chuan CHEN Xin Fu PAN Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

A novel enantioselective synthetic approach to 1,4-benzodioxane lignans was reported in which (2R, 3R)- and (2S, 3S)-2-(4-hydroxyphenyl)-3-hydroxymethyl-1, 4-benzodioxan-6-carbaldehyde were first synthesized.

关键词： Enantioselectivity synthesis 1 4-benzodioxane lignans.

A Novel Stereoselective Synthesis of 8-O-4' Neolignans

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Chinese Chemical Letters 2001年第2期12卷 109-110页

作者： xiao chuan CHEN Wen Xin GU xiao Bi JING Xin Fu PAN Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

1-(4-hydroxy-3-methoxyphenyl)-2-(4-formyl-2-methoxyphenoxy)-propane-1,3-diol. A 8-O-4' neolignan, has been stereoselectively synthesized in eight steps from ferulic acid, and the directly cis opening of epoxide in epo... 详细信息

关键词： 8-O-4’ Neolignans ferulic acid addition Mitsunobu reaction stereoselective synthesis

Accumulation of Zinc, Cadmium, and Lead in Four Populations of Sedum alfredii Growing on Lead/Zinc Mine Spoils

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Journal of Integrative Plant Biology 2008年第6期50卷 691-698页

作者： Dong-Mei deng Jin-chuan deng Jin-Tian Li Jun Zhang Min Hu Zhou Lin Bin Liao School of Life Sciences and State Key Laboratory of Biocontrol Sun Yat-sen University Guangzhou 510275 China Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 China Department of Environmental Science and Engineering Zhongkai Agrotechnical College Guangzhou 510225 China

Sedum alfredii Hance is a newly reported zinc （Zn） and cadmium （Cd） hyperaccumulator native to China. In this study, four populations of S. alfredii were collected from Yejiwei （YJW）, Jinchuantang （JCT） and Qiaokou （QK） lead （Pb）lZn mines located in Hunan Province as well as Quzhou （QZ） PblZn mine located in Zhejiang Province for exploring the intraspecies difference of this plant in metal accumulation. Although they grew in the PblZn spoils with relatively similar levels of Zn, Cd and Pb, remarkable differences among the four populations in tissue heavy metal concentrations were observed. The shoot Zn concentration of QZ population （11 116mglkg） was highest and nearly five times higher than that of the JCT population （1 930 mg/kg）. Furthermore, the shoot Cd concentration observed in the QZ population （1 090 mg/kg） was also highest and 144 times higher than that found in the JCT population （7.5 mg/kg）. As for Pb concentrations in the shoot of different populations, a fourfold difference between the highest and the lowest was also found. Such difference on metal accumulation was population-specific and may be significantly explained by differences in the soil properties such as pH, organic matter （OM）, and electrical conductivity （EC）. Taking biomass and metal concentration in plants into consideration, the QZ, YJW and QK populations may have high potential for Zn phytoremediation, the QZ population may have the highest potential in Cd phytoremediation, and the QK population may be the most useful in Pb phytoremediation.

关键词： heavy metal hyperaccumulation phytoremediation population Sedum alfredii

Efficient stochastic successive cancellation list decoder for polar codes

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Science China(Information Sciences) 2020年第10期63卷 133-151页

作者： xiao LIANG Huizheng WANG Yifei SHEN Zaichen ZHANG xiaohu YOU chuan ZHANG Laboratory of Efficient Architectures for Digital-communication and Signal-processing (LEADS) Southeast University National Mobile Communications Research Laboratory Southeast University Quantum Information Center of Southeast University

Polar codes are one of the most favorable capacity-achieving codes owing to their simple structures and low decoding complexity. Successive cancellation list(SCL) decoders with large list sizes achieve performances very close to those of maximum-likelihood(ML) decoders. However, hardware cost is a severe problem because an SCL decoder with list size L consists of L copies of a successive cancellation(SC)decoder. To address this issue, a stochastic SCL(SSCL) polar decoder is proposed. Although stochastic computing can achieve a good hardware reduction compared with the deterministic one, its straightforward application to an SCL decoder is not well-suited owing to the precision loss and severe latency. Therefore,a doubling probability approach and adaptive distributed sorting(DS) are introduced. A corresponding hardware architecture is also developed. Field programmable gate array(FPGA) results demonstrate that the proposed stochastic SCL polar decoder can achieve a good performance and complexity tradeoff.

关键词： SCL polar decoder stochastic computing 2-bit decoding distributed sorting hardware

Studies on ammonium dinitramide and 3,4-diaminofurazan cocrystal for tuning the hygroscopicity

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Chinese Journal of Chemical Engineering 2023年第9期61卷 157-164页

作者： Dongdong Hu Yinglei Wang chuan xiao Yifei Hu Zhiyong Zhou Zhongqi Ren State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Xi’an Modern Chemistry Research Institute Xi’an 710065China China Research and Development Academy of Machinery Equipment Beijing 10089China

Ammonium dinitramide(ADN)is a promising oxidizer with high energy characteristic,which is a relatively new environmentally friendly oxidizer without halogens and carbon ***,ADN has high hygroscopicity when exposed to high humidity air,restricting its applications on the solid *** this paper,a novel energetic cocrystal composed of ammonium dinitramide and 3,4-diaminofurazan(DAF)was proposed and successfully synthesized by antisolvent crystallization method,and the properties of the cocrystal were systematically investigated by analytical characterization and theoretical simulation *** formation of the cocrystal was confirmed by powder X-ray diffraction,differential scanning calorimetry,scanning electron microscopy,infrared spectroscopy and Raman spectroscopy,indicating that the synthesized product was a *** theoretical studies,the ADN/DAF cocrystal structure was predicted,and the powder X-ray diffraction,morphology,water sorption capacity of ADN/DAF cocrystal were calculated,which was consistent with experimental *** results showed that newly prepared cocrystal of ADN/DAF had lower hygroscopicity compared to pure ADN,and the water sorption capacity was reduced from 15.35%to 7.90%.This may be due to the formation of N-H…O medium-strength hydrogen bonds between the ammonium ion of ADN and the O atom of DAF in the cocrystal,which prevents the binding of water molecules in the air and ammonium ions and reduces the probability of ADN binding to water molecules,leading to the reduction of cocrystal *** newly prepared energetic cocrystal can provide theoretical and technical guidance for the study of the anti-hygroscopicity of ADN and advance the practical application of ADN.

关键词： Ammonium dinitramide 3,4-Diaminofurazan Hygroscopicity Cocrystallization Adsorption Kinetics

Secure hash function based on chaotic tent map with changeable parameter

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High Technology Letters 2012年第1期18卷 7-12页

作者： Li Yantao xiao Di deng Shaojiang College of Computer Science Chongqing UniversityChongqing 400044P.R.China

A new algorithm for a novel hash function, based on chaotic tent map with changeable parameter, is proposed and analyzed. The one dimensional and piecewise tent map with changeable parameters decided by the position index of blocked messages is chosen, and blocked massages translated into ASCII code values are employed as the iteration time of the chaotic tent map. The final 128-bit hash value is generated by logical XOR operation on intermediate hash values. Theoretical analysis and computer simulation indicate that the proposed algorithm can satisfy the performance requirements of hash function.

关键词： chaos the tent map hash function changeable parameter