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Chinese Journal of Chemistry 2020年第10期38卷 1052-1056页

作者： Hejiang luo chuan He Huanfeng jiang Shifa Zhu Key Laboratory of Functional Moleculor Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhouGuangzhou 510640China

Summary of main observation and conclusion A Cu(I)-catalyzed three-component reaction of terminal enynals/enynones,diazo compounds,and al kenes has been *** this method,a series of oxabicyclo[2.2.2]octanes were effectively synthesized in high yields under mild reaction *** transformation is proposed to proceed through trapping of the cyclic vinyl-o-quinodimethanes(vinyI-o-QDMs)species,which were generated from terminal enynals/enynones and diazo compounds by *** obvious advantages of wide substrate scopes,mild reaction conditions,and high seteroselectivity and atom eficiency make this reaction highly appealing for construction of highly rigid[2.2.2]octane skeleton.

关键词： octane ethane skeleton

Performance and Analysis of a Model for Describing Layered Leaf Area Index of Rice

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Agricultural Sciences in China 2011年第3期10卷 351-362页

作者： lu chuan-gen YAO Ke-min HU Ning Institute of Food Crops Jiangsu Academy of Agricultural Sciences Nanjing 210014 P.R. China College of Applied Meteorology Nanjing University of Information Science and Technology Nanjing 210044 P.R. China

Layered leaf area index （LAIk） is one of the major determinants for rice canopy. The objective of this study is to attain rice LAI k using morphological traits especially leaf traits that affected plant type. A theoretical model based on rice geometrical structure was established to describe LAI k of rice with leaf length （Li）, width （Wi）, angle （Ai）, and space （Si）, and plant pole height （H） at booting and heading stages. In correlation with traditional manual measurement, the model was performed by high R2-values （0.95-0.89, n=24） for four rice hybrids （Liangyoupeijiu, Liangyou E32, Liangyou Y06, and Shanyou 63） with various plant types and four densities （3 750, 2 812, 1 875, and 1 125 plants per 100 m2） of a particular hybrid （Liangyoupeijiu）. The analysis of leaf length, width, angle, and space on LAI k for two hybrids （Liangyoupeijiu and Shanyou 63） showed that leaves length and space exhibited greater effects on the change of rice LAI k . The radiation intensity showed a significantly negative exponential relation to the accumulation of LAI k , which agreed to the coefficient of light extinction （K）. Our results suggest that plant type regulates radiation distribution through changing LAI k . The present model would be helpful to acquire leaf distribution and judge canopy structure of rice field by computer system after a simple and less-invasive measurement of leaf length, width, angle （by photo）, and space at field with non-dilapidation of plants.

关键词： canopy structure layered leaf area index (LAI k ) model plant type rice

Cybersecurity Named Entity Recognition Using Bidirectional Long Short-Term Memory with Conditional Random Fields

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Tsinghua Science and Technology 2021年第3期26卷 259-265页

作者： Pingchuan Ma Bo jiang Zhigang lu Ning Li Zhengwei jiang School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China

Network texts have become important carriers of cybersecurity information on the *** texts include the latest security events such as vulnerability exploitations,attack discoveries,advanced persistent threats,and so *** cybersecurity entities from these unstructured texts is a critical and fundamental task in many cybersecurity ***,most Named Entity Recognition(NER)models are suitable only for general fields,and there has been little research focusing on cybersecurity entity extraction in the security *** this end,in this paper,we propose a novel cybersecurity entity identification model based on Bidirectional Long Short-Term Memory with Conditional Random Fields(Bi-LSTM with CRF)to extract security-related concepts and entities from unstructured *** model,which we have named XBi LSTM-CRF,consists of a word-embedding layer,a bidirectional LSTM layer,and a CRF layer,and concatenates X input with bidirectional LSTM *** extensive experiments on an open-source dataset containing an office security bulletin,security blogs,and the Common Vulnerabilities and Exposures list,we demonstrate that XBi LSTM-CRF achieves better cybersecurity entity extraction than state-of-the-art models.

关键词： security blogs Long Short-Term Memory(LSTM) Named Entity Recognition(NER)

Versatile Ti_(3)C_(2)T_(x)MXene for free-radical scavenging

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Nano Research 2022年第3期15卷 2558-2566页

作者： jiang Liu Wei lu Xifeng lu lu Zhang Haifeng Dong Yingchun Li Flexible Printed Electronics Technology Center and School of Science Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Department of Physiology Health Science CenterShenzhen UniversityShenzhen 518055China Marshall Laboratory of Biomedical Engineering Research Center for Biosensor and NanotheranosticSchool of Biomedical EngineeringShenzhen UniversityShenzhen 518055China

MXene,as an emerging two-dimensional(2D)material with ultrathin structure and fascinating physiochemical properties,has been widely explored in broad *** functions of MXenes are continuously *** work presents distinctive feature of MXene-Ti_(3)C_(2)T_(x)nanosheets for free-radical(FRs)scavenging that never reported *** demonstrated the mechanism and equation in regard to the reaction between Ti_(3)C_(2)T_(x)and H_(2)O_(2),which was applied to design colorimetric H_(2)O_(2)strip assay with good *** good FRs scavenging capability of Ti_(3)C_(2)T_(x),including a series of reactive oxygen species(ROS)and reactive nitrogen species(RNS),was systemically *** antioxidation capability of Ti_(3)C_(2)T_(x)for protecting cells from oxidative damage was demonstrated using the oxidative damage model of alpha mouse liver 12(AML-12)*** original work provides huge opportunities for MXenes in FR-related biomedical applications.

关键词： MXene hydrogen peroxide colorimetric sensor reactive oxygen species anti-oxidative damage

Evaluation of hadronic emission in starburst galaxies and star-forming galaxies

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Research in Astronomy and Astrophysics 2021年第10期21卷 221-230页

作者： Yun-chuan Xiang Ze-Jun jiang Yun-Yong Tang Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming 650091China School of Physical Science and Technology Kunming UniversityKunming 650214China

In this work,we reanalyzed 11 years of spectral data from the Fermi Large Area Telescope(Fermi-LAT)of currently observed starburst galaxies(SBGs)and star-forming galaxies(SFGs).We used a one-zone model provided by NAIMA and the hadronic origin to explain the GeV observation data of the SBGs and *** found that a protonic distribution of a power-law form with an exponential cutoff can explain the spectra of most SBGs and ***,it cannot explain the spectral hardening components of NGC 1068 and NGC 4945 in the GeV energy ***,we considered the two-zone model to well explain these *** summarized the features of two model parameters,including the spectral index,cutoff energy,and proton energy *** to the evolution of supernova remnants(SNRs)in the Milky Way,we estimated the protonic acceleration limitation inside the SBGs to be the order of 10^(2) TeV using the one-zone model;this is close to those of SNRs in the Milky Way.

关键词： galaxies:starburst galaxies:star formation gamma rays:galaxies radiation mechanisms:non-thermal

The likely counterpart to γ-ray excess from the northwest region of Arp 220

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Research in Astronomy and Astrophysics 2021年第7期21卷 171-176页

作者： Yun-chuan Xiang Jun-Hao Deng Ze-Jun jiang Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming 650091China

The unknown γ-ray excess in the northwest region of Arp 220 was revisited by analyzing~11.8 years of the Fermi Large Area Telescope(Fermi-LAT) data in this *** found that its photon flux was approximately three times higher than that of the previous study in the 0.2-100 GeV band,and the corresponding significance level ~8.15σ was approximately four times higher than *** light curves of 15 and 45 time bins from the whole time all showed two active periods,and the variability of the second period was more significant than that of the first *** spectral indices from the two active periods were not statistically different and were close to the range of γ-ray flat-spectrum radio quasars observed by *** the position of CRATES J153246+234400 was consistent with the best-fit position of our analysis,we suggest that CRATES J153246+234400 is more likely a γ-ray counterpart for the variational *** Arp 220,there was no significant variability in the γ-ray emission.

关键词： flat spectrum radio quasar:individual(CRATES J153246+234400) quasars γ-ray emission

Estimating stellar atmospheric parameters based on Lasso features

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Research in Astronomy and Astrophysics 2014年第4期14卷 423-432页

作者： chuan-Xing Liu Pei-Ai Zhang Yu lu Department of Mathematics Jinan University chool of Mathematical Sciences South China Normal University

With the rapid development of large scale sky surveys like the Sloan Digital Sky Survey （SDSS）, GAIA and LAMOST （Guoshoujing telescope）, stellar spectra can be obtained on an ever-increasing scale. Therefore, it is necessary to estimate stel- lar atmospheric parameters such as Teff, log g and [Fe/H] automatically to achieve the scientific goals and make full use of the potential value of these observations. Feature selection plays a key role in the automatic measurement of atmospheric parameters. We propose to use the least absolute shrinkage selection operator （Lasso） algorithm to select features from stellar spectra. Feature selection can reduce redundancy in spectra, alleviate the influence of noise, improve calculation speed and enhance the robustness of the estimation system. Based on the extracted features, stellar atmospheric param- eters are estimated by the support vector regression model. Three typical schemes are evaluated on spectral data from both the ELODIE library and SDSS. Experimental results show the potential performance to a certain degree. In addition, results show that our method is stable when applied to different spectra.

关键词： methods: data analysis -- stars: fundamental parameters -- techniques:spectroscopic -- surveys

A Survey on Quantum Image Processing

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Chinese Journal of Electronics 2018年第4期27卷 718-727页

作者： CAI Yongquan lu Xiaowei jiang Nan Faculty of Information Technology Beijing University of Technology

Quantum image processing is the intersection of quantum computation and image processing. Due to it is a newly emerging thing, researchers are facing not only great opportunities but also many challenges to develop more efficient and practicable services. We provide a comprehensive survey on quantum image processing to gather the current mainstream and discuss the advances made in the area, including quantum image representations, processing algorithms, and image measurement. Moreover,some open challenges and future directions are pointed out to attract continued research efforts.

关键词： Quantum image processing Quantum computation Quantum information Quantum image representation Quantum image compression Measurement

A flexible multiscale algorithm based on an improved smoothed particle hydrodynamics method for complex viscoelastic flows

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1387-1402页

作者： Jinlian REN Peirong lu Tao jiang Jianfeng LIU Weigang lu College of Mathematical Science Yangzhou UniversityYangzhou 225002Jiangsu ProvinceChina College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou 225002Jiangsu ProvinceChina

Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic ***,traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time,and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic *** this paper,a universal multiscale method coupling an improved smoothed particle hydrodynamics(SPH)and multiscale universal interface(MUI)library is presented for viscoelastic *** proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping *** test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic *** the first example,the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial *** effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping *** the second example,the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics(DPD)*** numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping ***,transferring different physical quantities has an important effect on the numerical results.

关键词： multiscale method improved smoothed particle hydrodynamics(SPH) dissipative particle dynamics(DPD) multiscale universal interface(MUI) complex viscoelastic flow

The generalized Bourgain-Sarnak-Ziegler criterion and its application to additively twisted sums on GL_(m)

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Science China Mathematics 2021年第10期64卷 2207-2230页

作者： Yujiao jiang Guangshi lu School of Mathematics and Statistics Shandong UniversityWeihaiWeihai 264209China School of Mathematics Shandong UniversityJinan 250100China

In this paper,we propose a new numerical scheme for the coupled Stokes-Darcy model with the Beavers-Joseph-Saffman interface *** use the weak Galerkin method to discretize the Stokes equation and the mixed finite element method to discretize the Darcy equation.A discrete inf-sup condition is proved and the optimal error estimates are also *** experiments validate the theoretical analysis.

关键词： the Bourgain-Sarnak-Ziegler theorem exponential sums automorphic L-function Sarnak’s conjecture