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A new data structure for accelerating kinetic Monte Carlo method

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Research in Astronomy and Astrophysics 2019年第12期19卷 235-244页

作者： Xu-Li Zheng dong-hui quan Hai-Long Zhang Xiao-Hu Li Qiang Chang Olli Sipila Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Department of Chemistry Eastern Kentucky UniversityRichmondKYUSA Max-Planck-Institute for Extraterrestrial Physics(MPE) Giessenbachstr.185748 GarchingGermany School of Astronomy and Space Science University of Chinese Academy of SciancesBeijing 100049China

The kinetic Monte Carlo simulation is a rigorous numerical approach to study the chemistry on dust grains in cold dense interstellar clouds. By tracking every single reaction in chemical networks step by step, this approach produces more precise results than other approaches but takes too much computing time. Here we present a method of a new data structure, which is applicable to any physical conditions and chemical networks, to save computing time for the Monte Carlo algorithm. Using the improved structure,the calculating time is reduced by 80 percent compared with the linear structure when applied to the osu-2008 chemical network at 10K. We investigate the effect of the encounter desorption in cold cores using the kinetic Monte Carlo model with an accelerating data structure. We found that the encounter desorption remarkably decreases the abundance of grain-surface H2 but slightly influences the abundances of other species on the grain.

关键词： astrochemistry molecular processes methods:numerical ISM:molecules ISM:abundances

On the encounter desorption of hydrogen atoms on an ice mantle

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Research in Astronomy and Astrophysics 2021年第2期21卷 113-120页

作者： Qiang Chang Xu-Li Zheng Xia Zhang dong-hui quan Yang Lu Qing-Kuan Meng Xiao-Hu Li Long-Fei Chen School of Physics and Optoeletronic Engineering Shandong University of TechnologyZibo 255000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Department of Chemistry Eastern Kentucky UniversityRichmondKY 40475USA School of Physics&Astronomy Sun Yat-Sen UniversityZhuhai 519082China

At low temperatures(10 K),hydrogen atoms can diffuse quickly on grain ice mantles and frequently encounter hydrogen molecules,which cover a notable fraction of grain *** desorption energy of H atoms on H2 substrates is much less than that on water *** H atom encounter desorption mechanism is adopted to study the enhanced desorption of H atoms on H_(2 )*** a small reaction network,we show that the steady-state surface H abundances predicted by the rate equation model that includes H atom encounter desorption agree reasonably well with the results from the more rigorous microscopic Monte Carlo *** a full gas-grain model,H atom encounter desorption can reduce surface H ***,if a model adopts the encounter desorption of H atoms,it becomes more difficult for hydrogenation products such as methanol to form,but it is easier for C,O and N atoms to bond with each other on grain surfaces.

关键词： astrochemistry-ISM abundances-ISM molecules

Constructing energetic covalent organic frameworks with high stability and low sensitivity

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Chinese Chemical Letters 2024年第3期35卷 544-548页

作者： hui-Min Guo Xiao-Yu dong Shan Wang Qian-You Wang Shuang-quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Green Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China

Developing new functional explosives that display high stability,good energy performance,and low sensitivity are one of the key directions of energetic materials *** this work,two-dimensional(2D)Schiff-based energetic covalent organic frameworks(COFs)are prepared based on triaminoguanidine salts with different anions as building *** from the robust covalent bond in 2D extended polygons and strongπ-πinteractions in the eclipsed interlayers,the synthesized energetic COFs showed higher thermal stability and lower mechanical sensitivity than their precursor *** importantly,incorporating triaminoguanidine salts into COFs effectively increase the corrosion resistance to metal under high humidity conditions,which is due to the imine moieties in COFs functioning asπacceptors and offering strong bonding with metallic *** work provides a new pathway for the development of high-performance energetic materials.

关键词： Covalent organic frameworks Energetic materials High thermal stability Low sensitivity Corrosion resistance

The BTB/TAZ domain-containing protein CmBT1-mediated CmANR1 ubiquitination negatively regulates root development in chrysanthemum

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Journal of Integrative Plant Biology 2024年第2期66卷 285-299页

作者： Lian-Da Du Zhang-Ji Guan Yan-Hong Liu hui-dong Zhu quan Sun Da-Gang Hu Cui-hui Sun Shandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient Production College of Horticulture Science and EngineeringShandong Agricultural UniversityTaian 271018China

Roots are fundamental for plants to adapt to variable environmental *** development of a robust root system is orchestrated by numerous genetic determinants and,among them,the MADS-box gene ANR1 has garnered substantial *** research has demonstrated that,in chrysanthemum,CmANR1positively regulates root system ***,the upstream regulators involved in the CmANR1-mediated regulation of root development remain *** this study,we successfully identified bric-a-brac,tramtrack and broad(BTB)and transcription adapter putative zinc finger(TAZ)domain protein CmBT1 as the interacting partner of CmANR1 through a yeasttwo-hybrid(Y2H)screening ***,we validated this physical interaction through bimolecular fluorescence complementation and pull-down *** assays revealed that CmBT1 exerted a negative influence on root development in *** both in vitro and in vivo assays,it was evident that CmBT1mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome *** ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2,which was crucial for root development in *** analysis suggested that CmBT1 modulated root development,at least in part,by regulating the level of CmANR1 ***,these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination,thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.

关键词： chrysanthemum MADS-box transcription factor root development

Measurement of acceleration and angular velocity of particles during a 3D silo discharge

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Particuology 2024年第9期92卷 61-71页

作者： Tongtong Mu Yiming Li quan Chen Ran Li hui Yang College of Medical Instrument Shanghai University of Medicine and Health SciencesShanghai201318China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China

Accurate measurement of the three-dimensional(3D)movement of discrete particles is crucial for comprehending complex granular rheology in *** this paper,the acceleration and angular velocity of particles in 3D silos are measured by using a spherical detector based on inertial technology and magnetic positioning *** acceleration of particles is the largest in the center of silos,which suggest that the resistance generated by friction and extrusion is the ***,the angular velocity distribution follows lognormal function except for particles near the *** correlation between acceleration and angular velocity is opposite in different flow *** reveals for the first time that the extent to which the resultant force on the particles affects their rotational motion is related to the flow *** results have practical significance for regulating the granular flow pattern and optimizing the structural design of silos.

关键词： Granularflow Silo Angular velocity Acceleration

On hypersurfaces of H2×H2

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Science China Mathematics 2024年第2期67卷 339-366页

作者： dong Gao hui Ma Zeke Yao School of Science Beijing University of Civil Engineering and Architecture Department of Mathematical Sciences Tsinghua University

In this paper, we study hypersurfaces of H2× H2. We first classify the hypersurfaces with constant principal curvatures and constant product angle functions. Then we classify homogeneous hypersurfaces and isoparametric hypersurfaces, respectively. Finally, we classify the hypersurfaces with at most two distinct constant principal curvatures, as well as those with three distinct constant principal curvatures under some additional conditions.

关键词： constant principal curvature homogeneous hypersurface isoparametric hypersurface 53C42 53B25 53C40

Neg-Entropy Mechanism as a Target for Natural Medicines

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Engineering 2024年第7期38卷 11-12页

作者： Tian-Le Gao hui-hui Guo Jian-dong Jiang Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Current strategies for drug discovery research mainly focus on molecular targets,in which structure biology plays a central role,such as the detailed mechanism of a drug-target *** principle of this approach is the presumed molecular mechanism or genetic background of the disease being *** this approach has brought progress in understanding the mode of action for some drugs,most prevalent illnesses-especially chronic diseases-are multifactorial and present with a group of symptoms,as is often the case in cardiovascular diseases,metabolic disorders,cancers,and so *** newly emerging term“multi-morbidity”(i.e.,multiple co-occurring diseases)describes a grand challenge for this strategy,and successful drug intervention for multimorbidity should be multifaceted[1].So,our research team has shifted its attention to a new direction that views the disease as a whole instead of a single-molecule abnormality,and focusing on drugs with multiple targets.

关键词： drugs diseases cardiovascular

Unveiling the impact and mechanism of digital technology on agricultural economic resilience

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Chinese Journal of Population,Resources and Environment 2024年第2期22卷 136-145页

作者： Tianshu quan hui Zhang Tianli quan Yi Yu College of Economics and Management Nanjing Forestry UniversityNanjing 210037China State Administration of Taxation Huai’an Taxation Bureau Huai’an 223300China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095China

Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural *** emergence of digital technology has created new opportunities in this ***,existing research predominantly focuses on traditional agricultural factors and ***,the impact of digital technology on agricultural economic resilience within the broader context of the“production-operation-industry”system in agriculture has not been comprehensively *** bridge this gap,this study analyzes panel data from 30 Chinese provinces from 2011 to *** employs the static Van Dorn’s law and a dynamic spatial panel model to examine how digital technology empowers agricultural *** findings indicate a continuous strengthening of digital technology development in China,albeit with significant polarization and spatial ***,the resilience of the agricultural economy undergoes notable fluctuations,initially narrowing and subsequently displaying an upward *** technology clearly plays a pivotal role in empowering resilience through agricultural scale operation,industrial transformation,and technological *** impact,particularly on the promotion of resilience in the eastern region and non-grain-producing areas and on high-level agricultural economies,also shows regional and technological variations.

关键词： Digital technology Agricultural economic resilience Counterfactual method Dynamic spatial panel model Agricultural scale

Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan LI Pei-wen XIAO Chao YING Xiao-hui LIU School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional *** to find their low-dimensional latent structure has been of great interest for *** this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction *** first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE *** asymptotic properties of both methods are derived under mild *** and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace