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ANALYSIS OF MOVING MESH METHODS BASED ON GEOMETRICAL VARIABLES

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Journal of Computational Mathematics 2001年第1期19卷 41-54页

作者： Tao Tang Wei-min Xue ping-wen Zhang Department of Mathematics The Hong Kong Baptist UniversityKowloonHong Kong School of Mathematics Peking UniversityBeijing 100871China

Examines the moving mesh methods for solving one-dimensional time dependent partial differential equations. Introduction of the differential-algebraic formulations based on geometrical variables; Investigation of the ... 详细信息

关键词： moving mesh methods partial differential equations adaptive grids

Effect of Potassium on Ultrastructure of Maize Stalk Pith and Young Root and Their Relation to Stalk Rot Resistance

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Agricultural Sciences in China 2010年第10期9卷 1467-1474页

作者： LI wen-juan HE ping JIN Ji-yun Key Laboratory of Plant Nutrition and Nutrient Cycling Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

To study the mechanism of potassium （K） application on improvement of maize resistance to stalk rot at cellular level, scanning electron microscope and transmission electron microscope were used to observe the effect of K on the ultrastructure of maize stalk pith tissue and young root tip cell influenced by K and pathogen. In K deficient treatment, parenchyma cells of stalk pith had abnormal structure, and the cell wall between upper and lower adjacent cell was damaged, resulting in the loss of connections between vascular cells and insufficient supporting capacity. However, an improved K nutrition helped to keep a quite tight arrangement of root cell with thick cell wall, and prevent the invasion of pathogen effectively. Moreover, K treated root cell had abundant golgi apparatus, which could excrete large amount of secretions to degrade mycelium. Papillary and highly electronic intensity dot were accumulated at the invading point to prevent the deveJopment of the mycelium. Improved K nutrition could increase the resistant ability of maize plant to stalk rot, through keeping cell structure stability, preventing the expansion of intracellular space to reduce the chances of pathogen invasions, and through reinforcing cell wall and formation of intercellular and intracellular material to restrict further development of pathogen in host cell.

关键词： potassium (K) maize stalk rot ultrastructure disease resistance

Fine-grained P2P traffic classification by simply counting flows

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Frontiers of Information Technology & Electronic Engineering 2015年第5期16卷 391-403页

作者： Jie HE Yue-xiang YANG Yong QIAO wen-ping DENG College of Computer National University of Defense Technology The Research Institution China Electronic Equipment & System Engineering Company

The continuous emerging of peer-to-peer(P2P) applications enriches resource sharing by networks, but it also brings about many challenges to network management. Therefore, P2 P applications monitoring, in particular,P2 P traffic classification, is becoming increasingly important. In this paper, we propose a novel approach for accurate P2 P traffic classification at a fine-grained level. Our approach relies only on counting some special flows that are appearing frequently and steadily in the traffic generated by specific P2 P applications. In contrast to existing methods, the main contribution of our approach can be summarized as the following two aspects. Firstly, it can achieve a high classification accuracy by exploiting only several generic properties of flows rather than complicated features and sophisticated techniques. Secondly, it can work well even if the classification target is running with other high bandwidth-consuming applications, outperforming most existing host-based approaches, which are incapable of dealing with this situation. We evaluated the performance of our approach on a real-world trace. Experimental results show that P2 P applications can be classified with a true positive rate higher than 97.22% and a false positive rate lower than 2.78%.

关键词： Traffic classification Peer-to-peer(P2P) Fine-grained Host-based

Melilite-derived mineral inclusions in chromite from the Gaositai complex: Implications for an extensional tectonic setting in Early Permian at the north North China Craton

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Science China Earth Sciences 2016年第3期59卷 583-589页

作者： SHAO Ji An TIAN Wei WEI Chun Jing ZHU wen ping Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University

The Early Permian mafic-ultramafic concentrically zoned Gaositai intrusion at Chengde, on the northern margin of the North China Craton(NCC), is a cumulative complex emplaced along a giant fracture that penetrates deeply into the continental lithosphere. Melt inclusions are present in chromite crystals from the inner dunite and chromitite zones of the Gaositai complex. The melt inclusions have experienced post-trap crystallization and resulted in multiple mineral phases, including melilite, garnet, phlogopite, magnesite and apatite, which can indicate the liquidus minerals of the primitive magma. The characteristics of the melilite+melanite+clinopyxene assemblage indicate that the primary parental magma was highly undersaturated and derived from an alkali-rich mantle source. The crystallization of phlogopite, magnesite and apatite suggests a primary magma rich in K, H_2O and CO_2. When compared with experimental data, the primary magma of the Gaositai intrusion is concordant with a kamafugite magma originating from partial melting of enriched mantle with H_2O and CO_2 at pressures greater than 2.7 GPa. This magmatic process would have been related to extensional thinning of the continental lithosphere. The Gaositai primary magmas have high Nb/La ratios, which are similar to those of ocean island basalts, but different from arc-related magmas. This suggests that the northern margin of the NCC was not an active continental margin of the Paleo-Asian Ocean subduction zone during the Early Permian: an extensional tectonic setting during the emplacement of the Gaositai intrusion is more likely.

关键词： Melt Inclusion Melilite Primary melt Extension Continental lithosphere North China Craton

Secure mediated certificateless signature scheme

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 75-78页

作者： YANG Chen MA wen-ping WANG Xin-mei Ministry of Education Key Laboratory of Computer Networks and Information Security Xidian University Xi'an 710071 China

Ju et al. proposed a certificateless signature scheme with instantaneous revocation by introducing security mediator （SEM） mechanism. This article presents a detailed cryptoanalysis of this scheme and shows that, in their proposed scheme, once a valid signature has been produced, the signer can recover his private key information and the instantaneous revocation property will be damaged. Furthermore, an improved mediated signature scheme, which can eliminate these disadvantages, is proposed, and security proof of the improved scheme under elliptic curve factorization problem （ECFP） assumption and bilinear computational diffie-hellman problem （BCDH） assumption is also proposed.

关键词： certificateless signature scheme bilinear pairing security mediator

黄芩苷与苦参碱分子间相互作用的量子化学计算与验证

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原子与分子物理学报 2025年第4期42卷 8-14页

作者：董志舒启江田爽王皎侯安国王文苹云南中医药大学中药学院云南省南药可持续利用重点实验室昆明650500

为探究苦参碱能极大增强黄芩苷在水中的溶解度的原因,采用量子计算对二者反应过程及共存状态进行分析,并使用单晶衍射和红外图谱验证计算结果.本研究表明,黄芩苷和苦参碱并非简单的以非共价作用相结合,二者存在质子转移现象,反应生成黄... 详细信息

为探究苦参碱能极大增强黄芩苷在水中的溶解度的原因,采用量子计算对二者反应过程及共存状态进行分析,并使用单晶衍射和红外图谱验证计算结果.本研究表明,黄芩苷和苦参碱并非简单的以非共价作用相结合,二者存在质子转移现象,反应生成黄芩苷阴离子和苦参碱阳离子,以静电作用为主导形成共无定型物,导致水溶性极大增加.

关键词：苦参碱黄芩苷质子转移离子共无定型物

The Henan extreme rainfall in July 2021: Modulation of the northward-shift monsoon trough on the synoptic-scale wave train

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Advances in Climate Change Research 2022年第6期13卷 819-825页

作者： Si-Hua HUANG Zhi-ping wen Xiao-Dan CHEN Yuan-Yuan GUO Zhe-wen WANG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Institute of Eco-Chongming(IEC) Shanghai 200062China Innovation Center of Ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 518057China Jiangsu Collaborative Innovation Center for Climate Change Nanjing 210023China Zhumadian Meteorological Office Zhumadian 463000China

The synoptic-scale wave train is a dominant pattern of the synoptic variability over the tropical western Pacific and usually affects the extreme weather over South China and Southeast *** it could extend its influence and contribute to the Henan extreme rainfall in July 2021 still needs to be *** found that during the Henan extreme rainfall days a positively synoptic-scale vorticity disturbance dominated Henan province,China,which was embedded in the synoptic-scale wave train that originated from the western North ***,the propagating pathway of this synoptic-scale wave train located northward and was likely modulated by the latitudinal location change of the monsoon trough over the western North Pacific.A northernmost displacement of the monsoon trough in July 2021(∼23.2°N)would facilitate the synoptic-scale wave train to propagate farther northwestward via shifting the related barotropic conversion ***,the synoptic-scale wave train from the tropics could reach Henan,provide the necessary lifting forcing,and supply abundant water vapor associated with the anomalous southerly for the occurrence of Henan extreme rainfall *** results implicate that the pre-existing synoptic-scale wave train regulated by the location of the monsoon trough may be a potential precursor for heavy rainfalls in northern Central China.

关键词： Extreme rainfall Northern Central China Synoptic-scale wave train Monsoon trough Barotropic energy conversion

Ti^(3+) self-doped TiO_(2) as a photocatalyst for cyclohexane oxidation under visible light irradiation

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Journal of Materiomics 2019年第4期5卷 696-701页

作者： ping wen Ying Zhang Guang Xu Di Ma ping Qiu Xiaoxia Zhao Department of Materials Science and Engineering China University of Petroleum(Beijing)Changping DistrictBeijing102249China The State Key Laboratory of Heavy Oil Processing China

Most of TiO_(2) particles can be used as a photocatalyst for the selective oxidation of cyclohexane under ultraviolet light *** this paper,Ti^(3+) self-doped TiO_(2) submicron-sized particles(i.e.,Ti^(3+)/TiO_(2) SMP)were used as a catalyst for visible-light driven photocatalytic cyclohexane *** microstructure and properties of the Ti^(3+)/TiO_(2) SMP were characterized by X-ray diffraction(XRD),UVevisible diffuse reflection(UVeVis DRS),scanning electron microscopy(SEM),electron paramagnetic resonance(EPR),solid-state photoluminescence spectroscopy(PLS)and X-ray photoelectron spectroscopy(XPS).The Ti^(3+)/TiO_(2) SMP exhibits good visible-light driven photocatalytic performances for cyclohexane oxidation with cyclohexanone as a dominate *** of solvent,reaction temperature,reaction time and oxygen pressure on the formation of cyclohexanone were *** cyclohexane oxidation over the Ti^(3+)/TiO_(2) SMP photocatalyst using carbon tetrachloride as a solvent under the optimal conditions presents a greater selectivity to cyclohexane(i.e.,95.1%).Based on the controlled experimental results with different radical scavengers,the hole(h^(+))is critical for the activation of cyclohexane.

关键词： Ti^(3+)self-doped TiO_(2) Cyclohexane oxidation Photocatalysis Selectivity

Chloro-propylene Sulfite as Electrolyte Additive for Li/S Batteries

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Chinese Chemical Letters 2006年第4期17卷 557-560页

作者： Guo Xiang XU Qi LU Lei wen ping HE Department of Applied Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871

Chloro-propylene sulfite （CIPS） was employed as electrolyte additive of Li/S batteries for the first time. Linear potential sweep test showed that the CIPS keeps high electrochemical stability even under the voltage of 5.0V. Being used as electrolyte additive in Li/S batteries, CIPS displayed an excellent property for self-discharge prohibition. With CIPS additive the Li/S cells initial discharge capacity was 856.2 mAh·g^-1 and 830.8 mAh·g^-1 at the current density of 15 mA.g and 30 mA·g^-1 , after 30 cycles the discharge capacities were contained at as high as 753.8 mAh.g and 715.6 mAh·g^-1. By means of infrared spectra, TG/DTA experiment and element conten analysis the speculated reason of CIPS＇s novel function as additive was proposed.

关键词： Chloro-propylene sulfite Li/S battery additive self-discharge capacity cycle.