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Defence Technology（防务技术） 2024年第2期32卷 644-654页

作者： Yabei Xu Jiankun Shao wei Wang Shengliang Xu dongping Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechnologyXiangyang 441003China

The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical ***,the impact of the above coupling on thermal hazard assessment is not considered in the literature *** this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical *** linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal *** thermal decomposition curves are decoupled by advanced thermokinetics *** thermal decomposition and kinetic parameters before and after decoupling are *** results of TG experiment show that both NQ and RDX began to lose mass during the endothermic *** endothermic melting and exothermic decomposition of NQ and RDX are coupled within this *** coupling effect has different degrees of influence on its initial decomposition temperature and safety *** with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling *** self-accelerating decomposition temperature increases,and internal thermal runaway time *** the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。

关键词： Calorimetric technologies Kinetics Thermal hazard Phase transformation Thermal decomposition

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网络安全中一种基于规则匹配的入侵检测方法

无线互联科技 2024年第11期21卷 120-124页

作者：周梦玲魏东平葛明珠尧时茂九江学院计算机与大数据科学学院江西九江332005

入侵检测方法在网络安全防线中承担监测网络异常流量、识别主机内部潜在威胁等至关重要的任务。然而,现有的入侵检测方法仍然面临一些挑战,如在收集和分析数据时对系统性能的损耗过大,导致许多入侵检测系统性能不高。此外,网络拥塞等导... 详细信息

入侵检测方法在网络安全防线中承担监测网络异常流量、识别主机内部潜在威胁等至关重要的任务。然而,现有的入侵检测方法仍然面临一些挑战,如在收集和分析数据时对系统性能的损耗过大,导致许多入侵检测系统性能不高。此外,网络拥塞等导致的数据丢包问题,使得数据完整性受到影响,间接影响入侵检测的效率和检测结果的准确性。为了应对这一挑战,有效提高系统效率和检测的准确性,文章提出一种基于规则匹配的入侵检测方法。该方法由数据收集、特征提取、异常检测3个步骤组成。模拟实验表明,该入侵检测方法能准确地监测和识别网络中的异常行为和潜在的安全威胁,并且实时监控流量行为,提高系统安全。

关键词：网络安全规则匹配入侵检测

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A Kinematic Thermal Model for Descending Slabs with Velocity Boundary Layers:A Case Study for the Tonga Subducting Slab

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 211-222页

作者： ZHANG Keliang wei dongping College of Earth Science Graduate University of the Chinese Academy of Sciences Beijing 100049 China

For the purpose of investigating the influence of metastable olivine（MO） phase transformations on both deep seismicity and stagnation of slabs,we constructed a 2-dimensional finite element thermal model for a 120 Ma-old 50°dipping oceanic lithosphere descending at 10 cm/yr with velocity boundary layers,which would mitigate the interference of constant velocity field for the slab. The resulting temperatures show that most of intermediate and deep earthquakes occurring within the Tonga slab are occurring inside the 800℃and 1200℃isotherm,*** elevation of olivine transformation near～410 km and respective persistence of metastable olivine and spinel within the transition zone and beneath 660 km would thus result in bimodal positive,zonal,negative density anomalies,*** results together with the resulting pressure anomalies may reflect the stress pattern of the Tonga slab：（i） slab pull force exerts above a depth of～230 km;（ii） MO existence changes the buoyancy force within the transition zone and facilitates slab stagnation at a depth of 660 km;（iii） as the subducting materials accumulated over 660 km,deepest earthquakes occur due to MO transformation;（iv） a flattened‘slab’ may penetrate into the lower mantle due to the density increment of Sp transformation.

关键词： kinematic thermal model subduction zone velocity boundary layer metastable olivine,double seismic zone finite element method

Heterobimetallic lanthanide tetrahedral cages:Synthesis,design and application for potential multimodal imaging contrast agent

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Journal of Rare Earths 2024年第2期42卷 278-285,I0002页

作者： Yongxiu Li Feng Guo Siwei wei Duofu Li Jun Zhang Kai Xu dongping Li Department of Chemistry Nanchang UniversityNanchang330031China Key Laboratory of Functional Molecule Design and Interface Process Anhui Jianzhu UniversityHefei230601China Department of Otolaryngology Head and Neck SurgeryThe Second Affiliated Hospital of Nanchang UniversityNanchang330006China

The construction and functionalization of lanthanide-organic cages have been a research hotspot in coordination *** from the unique luminescent and magnetic properties of lanthanide ions,the potential applications of lanthanide-organic cages in biological imaging applications are promising,but only a few corresponding explorations have been *** rein,we introduced a series of lanthanide tetrahedral cages,(Eu_(n)Gd_(4-n)L_(4))(sol)_8(n=0,1,2,3 and 4,where L=(4,4',4"-tris(4,4,4-trifluoro-1,3-dioxobutyl)-triphenylamine,and sol=dimethyl sulfoxide and methanol),with potential applications in biological *** the good luminescent and magnetic properties of Eu^(3+) and Gd^(3+) ions,Eu_(4)L_(4) and Gd_(4)L_(4) complexes show a high luminescence quantum yield of 29% in DMSO and large longitudinal relaxivity(r_(1)) of 11.4(mmol/L)^(-1)/s at 0.5 T in water containing 1 vol% DMSO,*** heterobimetallic Eu-Gd complexes achieve a dual imaging mode by combining luminescent and magnetic centers in one *** the Gd:Eu ratio increases from 1:3 to 3:1,the r_(1) values increases from 5.33 to 8.64(mmoI/L)^(-1)/s,higher than that of commercial contrast agent Gd-DOTA(3.23(mmol/L)^(-1)/s).Owing to their low toxicity and good cell imaging ability toward ECA 109 cells,the selfassembled Eu-Gd heterobimetallic tetrahedral cages could be potential candidates for the multimodal imaging contrast agent.

关键词： Lanthanide organic cage Luminescence Cell imaging Contrast agents Rare earths

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茉莉花和勿忘我花瓣在沐浴露中的应用

香料香精化妆品 2024年第3期 115-121页

作者：李秋芳李月菲梁瀚清韦冬萍海慧清龙致科广西警察学院广西南宁530028 柳州两面针股份有限公司广西柳州545001 广西民族大学广西南宁530006

为了找到合适的悬浮剂和防腐剂,在适当的条件下对花瓣进行处理,从而让花瓣在加入到沐浴露产品后,能够长期保持良好的形态,使用高效液相色谱仪(HPLC)和场发射扫描电子显微镜(FESEM)对茉莉花和勿忘我花瓣在预处理前后,以及置于沐浴露5年... 详细信息

为了找到合适的悬浮剂和防腐剂,在适当的条件下对花瓣进行处理,从而让花瓣在加入到沐浴露产品后,能够长期保持良好的形态,使用高效液相色谱仪(HPLC)和场发射扫描电子显微镜(FESEM)对茉莉花和勿忘我花瓣在预处理前后,以及置于沐浴露5年后的情况进行研究。结果表明,干花瓣采用沸水和强氧化剂处理后,脱去了色素和易挥发的成分;置于沐浴露中5年,依然能够保持花瓣形状完好且均匀悬浮,同时未发现微生物超标现象;由于花瓣中非挥发性物质减少,导致花瓣颜色变淡,质地变薄,但有利于花瓣形态在沐浴露配方中保持稳定。

关键词：茉莉花勿忘我花瓣沐浴露液相色谱扫描电镜

Tuning microstructures of TC4 ELI to improve explosion resistance

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Defence Technology（防务技术） 2024年第3期33卷 78-99页

作者： Changle Zhang Yangwei Wang Lin Wang Zixuan Ning Guoju Li dongping Chen Zhi-wei Yan Yuchen Song Xucai Wang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing 100081China State Key Laboratory of Explosive Science and Technology Beijing Institute of TechnologyBeijing 100081China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Aeronautical Engineering Zhengzhou University of AeronauticsHenan ProvinceZhengzhou 450046China Shanxi Jiangyang Chemical Co. Ltd.Shanxi ProvinceTaiyuan 030041China Shandong Institute of Non-metallic Materials Shandong ProvinceJinan 250031China

A reasonable heat treatment process for TC4 ELI titanium alloy is crucial to tune microstructures to improve its explosion ***,there is limited investigation on tuning microstructures of TC4 ELI to improve explosion ***,the current challenge is quantifying microstructural changes'effects on explosion resistance and incorporating microstructural changes into finite element *** work aims to tune microstructures to improve explosion resistance and elucidate their anti-explosion mechanism,and find a suitable method to incorporate microstructural changes into finite element *** this work,we systematically study the deformation and failure characteristics of TC4 ELI plates with varying microstructures using an air explosion test and LS-DYNA finite element *** Johnson-Cook(JC)constitutive parameters are used to quantify the effects of microstructural changes on explosion resistance and incorporate microstructural changes into finite element *** of the heat treatment,one plate has equiaxed microstructure and the other has bimodal *** convex of the plate after the explosion has a quadratic relationship with the charge mass,and the simulation results demonstrate high reliability,with the error less than 17.5%.Therefore,it is feasible to obtain corresponding JC constitutive parameters based on the differences in microstructures and mechanical properties and characterize the effects of microstructural changes on explosion *** bimodal target exhibits excellent deformation *** response of bimodal microstructure to the shock wave may be more intense under explosive *** well-coordinated structure of the bimodal target enhances its resistance to deformation.

关键词： Microstructure Finite element modelling Parameter optimization Failure characteristics Explosion resistance

Zeolite-confined Fe-site Catalysts for the Hydrogenation of CO_(2) to Produce High-value Chemicals

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Chemical Research in Chinese Universities 2024年第1期40卷 78-95页

作者： HAN Xiaoyang XIA Huicong TU weifeng wei Yifan XUE dongping LI Minhan YAN Wenfu ZHANG Jia-Nan HAN Yi-Fan College of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001P.R.China State Key Laboratory of Coking Coal Resources Green Exploitation Zhengzhou UniversityZhengzhou450001P.R.China Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education School of Chemical EngineeringZhengzhou UniversityZhengzhou450001P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry and College of Chemistry Jilin UniversityChangchun130012P.R.China State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237P.R.China

Zeolite-confined Fe-site catalysts(ZFCs)have emerged as superior materials for sustainably producing high-value chemicals through CO_(2) hydrogenation,owing to their adaptable framework,customizable composition,and thermal *** excel in activating,adsorbing,and converting CO_(2) with remarkable efficiency and consistency in *** has sparked a surge in research interest in recent *** review delves into the latest advancements in CO_(2) catalytic hydrogenation to olefins,alcohols,aromatics,and other liquid hydrocarbons,examining the synthesis,modification tactics,and the correlation between structure and performance across various ***,it underscores the pivotal factors affecting performance and sheds light on the mechanisms behind selectivity control in the CO_(2) hydrogenation process facilitated by *** conclude,it presents pressing challenges and strategic recommendations to inspire the development of high-performance,durable ZFCs for CO_(2) hydrogenation applications.

关键词： Zeolite-confined Fe-site catalyst CO_(2) hydrogenation Modification strategy High-value chemical

Correlation between plate age and layer separation of double seismic zones

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Earthquake Science 2012年第1期25卷 95-101页

作者： Keliang Zhang and dongping wei State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Key Laboratory of Computational Geodynamics Chinese Academy of SciencesBeijing 100049China College of Earth Science Graduate University of Chinese Academy of SciencesBeijing 100049China

Global seismicity catalogs are sufficient for characterizing double seismic zones （DSZs） in subducting slab and facilitate to estimate layer separation without inconsistent uncertainties as local catalogs. Previous studies have shown the correlation between DSZs layer separation and plate age while correlation for those younger than -60 Ma is suspicious. The lacking of DSZs with layer separation less than 10 km further makes it difficult to precisely estimate such correlation. Thus, we incorporate eight DSZs data determined through local seismicity into globally-determined dataset and reexamine such correlation. The best fitting results show that both a linear model and a square root of plate age can mathematically fit the layer separation well. However, it is difficult to distinguish these two models when plate age is greater than -20 Ma since their difference is less than 2 km. However, if extrapolation is possible, both models should provide physical information that DSZs will not form if there is no subducting lithosphere. As a result, the DSZs cannot be produced until the oceanic lithospheric age becomes greater than 0.9 Ma in the square root model while the linear model gives a misleading result. As such the square root model demonstrates the relationship physically better than the linear one, it still needs further test in the future with more available data, nevertheless, our study might also provide evidence for the suggestion that the plate age is a primary control factor of the DSZs geometry as well as the subducting process which disregards any local tectonic stresses.

关键词： double seismic zone layer separation plate age correlation best fitting

Implicit expansion rate of the Earth in global plate motions

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Geodesy and Geodynamics 2019年第3期10卷 228-234页

作者： Changyi Xu Xiao Yu dongping wei Institute of Earthquake Forecasting China Earthquake AdministrationBeijingChina Institute of Earth Sciences Academia SinicaTaipeiTaiwan Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijingChina

Based on eight published plate motion models, we separately estimated the net area changes of tectonic plates and the area change of the solid Earth surface over geological time using the Euler vectors of plates with determined boundaries. Then, under the context of a currently expanding Earth, we inferred the change rate of the Earth’s mean radius from the estimated net area changes. The results show that the total increases and decreases in the areas of different plates cannot be compensated. Specifically, the area of the Northern Hemisphere decreases while that of the Southern Hemisphere increases, but the net area of the solid Earth surface slightly increases in th computing period(0.01 Ma). For the latest NNRMORVEL56 plate motion model, the area of the Southern Hemisphere increases by 7802 km2 while the area of the Northern Hemisphere decreases by 7711 km^2. This indicates a net area increase of 91 km2 in the solid Earth surface corresponding to an expansion rate of 0.06 mm/a for the Earths mean *** result coincides with the slow rate of expansion derived from geodetic measurements and geophysical modeling.

关键词： Plate motion model Area change of plate boundary Earth expansion

Near-surface Geothermal Gradient Observation and Geothermal Analyses in the Xianshuihe Fault Zone,Eastern Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 414-428页

作者： LIU Qianqian SHI Yanan wei dongping HAN Peng CHEN Shunyun LIU Peixun LIU Liqiang Key Laboratory of Computational Geodynamics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration

The Xianshuihe fault（XSHF） zone, characterized by intense tectonic activity, is located at the southwest boundary of the Bayan Har block, where several major earthquakes have occurred, including the 2008 Wenchuan and the 2013 Lushan earthquakes. This study analysed underground temperature sequence data for four years at seven measuring points at different depths（maximum depth： 18.9 m） in the southeastern section of the XSHF zone. High-frequency atmospheric noise was removed from the temperature sequences to obtain relatively stable temperature fields and heat fluxes near the measurement points. Our measurements show that the surrounding bedrock at（the seven stations distributed in the fault zone） had heat flux values range from-41.0 to 206 m W/m^2, with a median value of 54.3 m W/m^2. The results indicate a low heat flux in the northern section of DaofuKangting and a relatively high heat flux in the southern section of Kangting, which is consistent with the temperature distributions of the hot springs near the fault. Furthermore, our results suggest that the heat transfer in this field results primarily from stable underground heat conduction. In addition, the underground hydrothermal activity is also an obvious factor controlling the geothermal gradient.

关键词： temperature sequence records geothermal gradient heat flow heat flux Xianshuihe fault zone Tibet Plateau Proto-Tethys