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Defence Technology（防务技术） 2021年第4期17卷 1289-1295页

作者： jia-xing Song tao Guo Miao Yao jia-lin Chen Wen Ding Feng-li Bei Xiao-nan Zhang Qin Yin Jun-yi Huang Chang-hao Li College of Field Engineering PLA Army Engineering UniversityNanjing210001China School of Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Tellhow Sci-Tech CO. LTD.Beijing100032China

Fluoropolymers get increasing attention in energetic materials application due to the high fluorine *** explore the effect of poly(vinylidene fluoride-co-hexafluoropropylene)(P(VDF-HFP))on Al/MnO_(2) nanothermite,the samples with different contents are prepared and characterized by SEM,TGDSC,XRD,and their ignition and combustion behavior are tested and *** results show that P(VDF-HFP)as an energetic binder can combine the nanothermite components together,even exist in the *** integrity of energetic materials has been *** analysis shows that the addition of P(VDF-HFP)greatly changes the thermal reaction processes,and the exothermic peaks appear early,but the utilization of fuel and oxidizer is not efficient from the XRD ***,the appropriate addition of P(VDF-HFP)can directly reduce the ignition energy threshold and increase the combustion time,which is necessary for the potential ignition charge *** possible reasons for above phenomena are discussed and *** research provides a reference for improvement of thermitebased ignition charge formulation.

关键词： Nanothermite Fluoropolymers Combustion Thermal analysis

Iontronic components: From liquid- to solid-states

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Nano Research 2023年第12期16卷 13343-13357页

作者： tao Xiao xing Zhao Yuchun Zhang Yong Yan CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China

In modern electronics,the ionic charges have not occupied the same role as the electrons mainly because of their relatively low ***,these“slow”charge carriers contribute to brain computing with high efficiency and extremely low power *** by the“ionic”life,iontronic components have recently attracted considerable *** this review,we first introduce the progress of iontronic devices operating with the involvement of water,specifically,two types of systems—nanofluidic and ***,the issues and challenges within these liquid-state ionic devices are *** avoid the negative impact of water,we also propose two solid-state materials—ionogels and charged metal nanoparticles—to construct several basic ionic devices such as diodes and ***,we summarize this review and outlook the promising directions for the further developments of iontronic devices.

关键词： ionic charges liquid-/solid-state diode transistor

C:N:P stoichiometry of perennial herbs’ organs in the alpine steppe of the northern Tibetan Plateau

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Journal of Mountain Science 2019年第9期16卷 2039-2047页

作者： MA xing-xing HONG jiang-tao WANG Xiao-dan College of Geographical Sciences Shanxi Normal University Linfen 041000 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

The patterns of C:N:P stoichiometry across ecosystems are important in understanding biogeochemical processes. The stoichiometry of nutrients at the leaf and root level have been reported previously, but relationships of other plant organs, such as stems and the reproductive organs, remain unclear. We collected 228 samples of leaves, roots, stems and reproductive organs from 11 common plant species at 25 sites on the Tibetan Plateau to explore the relationships of C:N:P stoichiometry both within and across plant organs. The average C concentrations in the roots, leaves, stems and reproductive organs were 427.32, 410.51, 421.11 and 416.72 mg g-1, respectively. The shoot tissues(leaves, stems and reproductive organs) had significantly higher N and P concentrations than the roots. The N and P concentrations had a significant positive correlation within the same organ. The nutrient concentrations(N and P) and nutrient ratios(C:N, C:P and N:P) were significantly correlated across all pairwise organ combinations. Our data suggest that alpine perennial herbs share similar evolutionary histories and have constrained patterns of covariation for C concentrations, with differential patterns for N and P stoichiometry across organs. Our data also indicate that covarying sets of nutrient traits are consistent across environments and biogeographical regions and demonstrate convergent evolution in plant nutritional characteristics in extreme alpine environments.

关键词： Shoot tissues Chemical elements Biogeochemical process Alpine steppe Tibet Plateau

Fault-tolerant stator flux oriented decoupling control for dual three-phase permanent magnet motor without diagnosis and reconfiguration

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Science China(Technological Sciences) 2023年第11期66卷 3206-3218页

作者： HUANG LinSen ZHAO WenXiang tao tao CUI jia ZHANG Qiang School of Electrical and Information Engineering National Center for International Research on Structural Health Management of Critical ComponentsJiangsu UniversityZhenjiang 212013China

In this paper,the fault-tolerant capability of the existing stator-flux-oriented decoupling control(SFOC)for the DTP-PM motor is investigated,and a simple fault-tolerant SFOC is further designed to enhance fault ***,the mathematical model of the DTP-PM motor in the stator-flux-oriented rotating coordinate system is *** SFOC is proposed to guarantee healthy operation performance,considering torque,flux linkage,and harmonic ***,the coupling relationship under open-phase conditions is *** assessed result shows that the coupling relationship between the harmonic and fundamental components results in conflicts and poor post-fault ***,the proposed SFOC includes an automatic deactivation module to detect conflicts with a variable *** conflicted harmonic current controllers can be excluded ***,fault-tolerant control can be remedied without diagnosing the specific fault scenario,and excellent faulttolerant capability can be ***,experiments on a DTP-PM motor are carried out to verify the feasibility and effectiveness of the proposed strategy.

关键词： dual three-phase motor stator flux orientation decoupling control fault-tolerant control open-phase fault

Improvement of typhoon rainfall prediction based on optimization of the Kain-Fritsch convection parameterization scheme using a micro-genetic algorithm

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Frontiers of Earth Science 2019年第4期13卷 721-732页

作者： jia ZHU Jiong SHU xing YU Key Laboratory of Geographic Information Science(Ministry of Education) East China Normal UniversityShanghai 200241China School of Geographic Sciences East China Normal UniversityShanghai 200241China Beijing Thematic Technology Co. Ltd.Beijing 100020China

Inclusion of cloud processes is essential for precipitation prediction with a numerical weather prediction ***,convective parameterization contains numerous parameters whose values are in large *** particular,it is still not clear how the parameters of a sub-grid-scale convection scheme can be modified to improve high-resolution precipitation *** address these issues,a micro-genetic(micro-GA)algorithm is coupled to the Kain-Fritsch(KF)convective parameterization scheme(CPS)in the WRF to improve the quantitative precipitation forecast(QPF).The optimization focuses on two parameters in the KF scheme:the convective time scale and the conversion *** optimizing process is controlled by the micro-GA using a QPF skill score as the fitness *** heavy rainfall events related to typhoons that made landfall over the south-east coastal region of China are selected,and for each case the parameter values are adjusted to achieve the best QPF *** improvements in QPF are evident with an increase in the average equitable threat score(ETS)by 5.8%for the first case,and by 18.4%for the second *** results demonstrate that the micro-GAKF coupling system is effective in optimizing the parameter values,which affect the applicability of CPS in a high-resolution model,and therefore improves the rainfall prediction in both ETS and spatial distribution.

关键词： quantitative precipitation forecast micro-GA Kain-Fritsch scheme typhoon

不同禾本科植物对矿区重金属污染土壤的修复效果研究

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陕西科技大学学报 2025年第1期43卷 23-28页

作者：贾红磊安昊东王晴李成涛陕西科技大学环境科学与工程学院陕西西安710021

以秦岭腹地凤县典型铅锌尾矿区周边的农田土壤为研究对象,采用黑麦草、剪股颖、百慕大草三种类型的草本植物进行室内盆栽实验,阐述了干旱胁迫对植物生长的影响,探究不同禾本科植物在干旱半干旱地区对重金属污染土壤的修复效果,以期筛选... 详细信息

以秦岭腹地凤县典型铅锌尾矿区周边的农田土壤为研究对象,采用黑麦草、剪股颖、百慕大草三种类型的草本植物进行室内盆栽实验,阐述了干旱胁迫对植物生长的影响,探究不同禾本科植物在干旱半干旱地区对重金属污染土壤的修复效果,以期筛选出能够适合在金属矿区修复中种植的耐旱性草本植物.结果表明:相比剪股颖和百慕大草,黑麦草在该土壤条件下能够具有较高的生物量累积,且在干旱条件下生物量降低的较少(P<0.05),黑麦草的丙二醛(MDA)含量与电导率(EC)较低,说明其具有较好的耐旱能力和较高的重金属耐受能力(P<0.05).在重金属污染土壤修复中,黑麦草中Cd、Pb和Zn的含量最高,且对Cd的富集系数可达到0.98,种植黑麦草对土壤中Cd的去除效率高达50%以上,Pb的去除效率为15.5%.因此,研究认为黑麦草对于凤县矿区Pb、Zn和Cd污染土壤具有更好的修复潜力.

关键词：重金属干旱土壤修复植物筛选

Homogenization of a Nonlinear Degenerate Parabolic Differential Equation

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Acta Mathematica Sinica,English Series 2013年第7期29卷 1429-1436页

作者： Hai tao CAO xing Ye YUE Department of Mathematics and Physics Changzhou Campus Hohai University Department of Mathematics Soochow University

This paper is devoted to the homogenization of a nonlinear degenerate parabolic problemwith Dirichlet boundary condition. Here the operator D（y, s, △s） is periodic in y and degenerated in △s. In the paper, under the two-scale convergence theory, we obtain the limit equation as ∈ → 0 and also prove the corrector results of △u^∈ to strong convergence.

关键词： Nonlinear degenerate parabolic equation homogenization two-scale convergence

On the Unique Continuation Properties for Elliptic Operators with Singular Potentials

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Acta Mathematica Sinica,English Series 2007年第2期23卷 297-308页

作者： Xiang xing tao Song Yan ZHANG Department of Mathematics Faculty of ScienceNingbo University

Let u be a solution to a second order elliptic equation with singular potentials belonging to Kato-Fefferman-Phong＇s class in Lipschitz domains. An elementary proof of the doubling property for u^2 over balls is presented, if the balls are contained in the domain or centered at some points near an open subset of the boundary on which the solution u vanishes continuously. Moreover, we prove the inner unique continuation theorems and the boundary unique continuation theorems for the elliptic equations, and we derive the Bp weight properties for the solution u near the boundary.

关键词： doubling property unique continuation Lipschitz domain Kato-Fefferman-Phong's potential

An Optimal Control Problem of a Coupled Nonlinear Parabolic Population System

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 377-388页

作者： Chao-hua jia De-xing Feng Department of Applied Mathematics LMIB of the Ministry of Education Beijing University of Aeronauticsand Astronautics Beijing 100083 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

An optimal control problem for a coupled nonlinear parabolic population system is considered. The existence and uniqueness of the positive solution for the system is shown by the method of upper and lower solutions. An explicit prior bound of solutions to the system is given by considering an auxiliary coupled linear system. The existence of the optimal control is proved and the characterization of the optimal control is established.

关键词： Nonlinear parabolic systems optimal control upper and lower solutions

Boundedness for multilinear fractional integral operators on Herz type spaces

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 437-446页

作者： SHI Yan-long tao Xiang-xing Dept. of Math. Faculty of Science Ningbo Univ. Ningbo 315211 China

In this paper the boundedness for the multilinear fractional integral operator Iα^（m） on the product of Herz spaces and Herz-Morrey spaces are founded, which improves the Hardy- Littlewood-Sobolev inequality for classical fractional integral Iα. The method given in the note is useful for more general multilinear integral operators.

关键词： multilinear fractional integral Herz space homogeneous Herz-Morrey space product space