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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

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

Microstructure and properties of LZQT600-3 HCCDIBs for plunger pump cylinder

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China Foundry 2024年第2期21卷 197-204页

作者： Chun-jie Xu Yuan-ying Jin dong Ma Zhen Zhao Jia-wei Qi Shang Sui Xiang-quan Wu Can Guo Zhong-ming Zhang Yong-hui Liu Dan Shechtman School of Materials Science and Engineering Xi'an University of TechnologyXi'an 710048China Xi'an Shechtman Nobel Prize New Materials Institute Xi'an 710048China Tongchuan Huazhu Precision Technology Co. Ltd.Tongchuan 727100ShaanxiChina Faculty of Materials Science and Engineering Technion-Israel Insititue of TechnologyHaifa 3200003Israel

It is important to improve the comprehensive performance of the ductile iron bars(DIBs)for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial *** this work,the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting(HCC)process,that is,LZQT600-3 *** microstructure and room temperature tensile properties of different sections[left-edge(surface layer),left-1/2R(left half of the radius),and the center of the HCCDIBs]were *** results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge,left-1/2R to the center is at nodulizing grade II and *** the cooling rate gradually decreases from surface to the center of the HCCIBs,the number of spheroidized graphite is gradually reduced,the size is gradually increased,the shape factor is decreased,and the pearlite content and lamellate spacing are *** the horizontal direction of the section,the hardness of the material is distributed symmetrically around the center of the *** the vertical direction,the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification ***,the microstructure in the lower part of the section solidifies relatively *** left-edge has the best tensile mechanical properties,and the ultimate tensile strength,yield tensile strength and elongation are 597.3 MPa,418.5 MPa and 9.6%,*** tensile fracture belongs to the ductile-brittle hybrid *** comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder.

关键词： horizontal continuous casting(HCC) nodular cast iron ductile iron bars microstructure mechanical properties

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大规模网络负面信息准确评估分类研究

计算机仿真 2016年第12期33卷 296-299,410页

作者：董会权长春工业大学人文信息学院吉林长春130122

对大规模网络负面信息准确评估分类,可以保证大规模网络的健康运行。大规模网络中负面信息的种类很多,容易形成信息淹没效应,很难找出负面信息的特有属性对信息聚类过程进行约束,只能通过不断细化负面信息特有信息,找到最优约束完成信... 详细信息

对大规模网络负面信息准确评估分类,可以保证大规模网络的健康运行。大规模网络中负面信息的种类很多,容易形成信息淹没效应,很难找出负面信息的特有属性对信息聚类过程进行约束,只能通过不断细化负面信息特有信息,找到最优约束完成信息分类,而传统的神经网络算法主要通过复杂的网络结构对信息样本进行训练,没有明确的最优约束范围,降低了大规模网络负面信息准确评估分类的精度和效率。提出粗糙集理论和神经网络相结合的大规模网络负面信息准确评估分类方法。利用粗糙集理论的属性对大规模网络负面信息进行预处理降低维度,获得约简的决策规则。运用决策规则语义构建一种神经网络的分类机理。并根据分类机理对高维网络参数进行初始化来提高收敛速度,对高维网络输入的特征属性的离散化值通过蚁群算法进行寻优,获得最优的负面信息的分类结构。仿真结果表明,改进算法能够提高大规模网络负面信息准确评估分类的效率和精度。

关键词：神经网络粗糙集理论决策规则蚁群算法