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Numerical simulation of radiated noise during combustion of energetic materials in a closed bomb

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Defence Technology（防务技术） 2022年第7期18卷 1167-1178页

作者： Shi-hui Xiong Tuo Yang yu-jun wu Jing-cheng Wang yuan Li yu-quan Wen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Xi'an Qinghua Cooperation North Special Energy Group Co.Ltd.Xi'an710025China Institute of Extreme Mechanics and School of Aeronautics Northwestern Polytechnical UniversityXi'an710072China

In this study,based on a closed bomb test combined with computational fluid dynamics,a structural finite element method,and an acoustic boundary element method,a fluid-solid acoustic one-way coupling calculation model is established for the combustion process of energetic materials in a closed bomb,and the effectiveness of the model is verified by *** is found that the maximum peak sound pressure increases exponentially with an increase in loading doses or gas ***,a change in the combustion coefficient of the energetic materials has little effect on the noise generated during the combustion process in the closed *** the combustion coefficient is reduced by a multiple of 16,the maximum transient sound pressure is reduced by 1.79 dB,and the sound pressure level in the frequency band is reduced by 1.75 *** an increase in shell thickness,the combustion noise of the energetic materials in the closed bomb decreases,and the reduction range of the combustion noise increases with the increase in shell thickness.

关键词： Pyrotechnics Noise Energetic materials Fluid-structure interaction Acoustic boundary element

利用曲率多特征融合改进人体三维脊椎模型特征点的标注方法

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光学精密工程 2016年第11期24卷 2872-2879页

作者：惠宇武君胜鱼滨张琛武震西北工业大学计算机学院陕西西安710072 西北工业大学软件与微电子学院陕西西安710072 西安电子科技大学计算机学院陕西西安710072

由于脊椎生理结构的精准坐标描述和准确匹配尚未达到医学精度的要求,本文对如何精确描述脊柱腰骶段特征点的物理坐标进行研究。介绍了人体脊椎采样特征点的定义和传统标记方法。针对手动标注特征点精确度不够,易产生较大误差等问题提出... 详细信息

由于脊椎生理结构的精准坐标描述和准确匹配尚未达到医学精度的要求,本文对如何精确描述脊柱腰骶段特征点的物理坐标进行研究。介绍了人体脊椎采样特征点的定义和传统标记方法。针对手动标注特征点精确度不够,易产生较大误差等问题提出了一种基于曲率多特征融合的自适应标注特征点的方法。该方法首先找出某个特征点的高斯曲率和平均曲率流的定义值,得到该特征点的法曲率相对极大值,并计算在指定极小半径r范围内的所有模型点的法曲率相对极大值。由于极大值曲率越大,三维模型表面在该点处的弯曲程度越大,该点就越能表现三维模型的大致轮廓,故以r范围内极大值最大的点作为特征点的曲率描述来替换手动拾取的点,从而准确反映该点的特征变化情况。最后,对改进结果进行偏差验证分析。结果表明:改进方法的准确度比现有手动标注特征点方法的准确度提高了约37%,验证了本文方法的有效性。

关键词：脊椎三维模型特征点标注曲率多特征融合极大值曲率

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao wu Xiaoling Liu Biao Meng Tao Chen yu Han jun Wang Shibo Xi yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect Carbon catalyst Electrocatalysis

Fast Evaluation of Oxidative DNA Damage by Liquid Chromatography-Electrospray Tandem Mass Spectrometry Coupled With Precision-cut Rat Liver Slices

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Biomedical and Environmental Sciences 2007年第5期20卷 386-391页

作者： JIANG yuE PENG WANG YING-HUI LIU jun-yu wu JIE CHEN REN-XIU PENG Department of Pharmacology College of Basic Medicine Wuhan University Wuhan 430071 Hubei China Inspection ＆ Quarantine Technical Center Hubei Entry-exit Inspection and Quarantine Bureau Wuhan 430022 Hubei China

Objective To establish a fast and sensitive method for the detection of 8-hydroxy-2’-deoxyguanosine （8-OHdG） in precision-cut rat liver slices by HPLC-MS/MS and to investigate isoniazid （INH） -induced oxidative DNA damage. Methods Precision-cut liver slices （300 μm） were prepared from male rats, and incubated with INH （0.018 mol/L） for 2 h after 1 h preincubation. DNA in the slices was extracted and digested into free nucleosides at 37℃ . The samples were injected into HPLC-MS/MS after the proteins were removed. The level of oxidative DNA damage was estimated using the ratio of 8-OHdG to deoxyguanosine （dG）. Results The limit of detection of 8-OHdG was 1 ng/mL （S/N=3） and the intra-assay relative standard variation was 3.38% when one transition 284.3/168.4 was used as a quantifier and another two transitions 284.3/140.2, 306.1/190.2 as qualifiers. 8-OHdG and dG were well separated, as indicated by elution at 10.02 and 7.37 min, respectively. INH significantly increased the ratio of 8-OHdG to dG in rat liver slices （P〈0.05）. Conclusion 8-OHdG in precision-cut liver slices could be sensitively determined by HPLC-MS/MS. HPLC-MS/MS coupled with precision-cut tissue slices is a fast and reliable analytical technique to evaluate oxidative DNA damage of target tissues caused by procarcinogens and cytotoxins.

关键词： Isoniazid 8-Hydroxy-2'-deoxyguanosine HPLC-MS/MS Precision-cut liver slices

Effect of integration of mechanical ball milling and flue gas desulfurization gypsum on dealkalization of bauxite residue

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Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2702-2713页

作者： Feng ZHU Xu-yao GUO jun JIANG Kai-bin CHEN Xuan-zhi ZHU Dan-dan DENG yu-jun wu yu-wei HUANG Sheng-guo XUE School of Metallurgy and Environment Central South UniversityChangsha 410083China Zhengzhou Non-ferrous Metals Research Institute Co. Ltd.of CHALCOZhengzhou 450041China College of Environment and Resources Xiangtan UniversityXiangtan 411105China School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The synergistic impact of mechanical ball milling and flue gas desulfurization(FGD)gypsum on the dealkalization of bauxite residue was investigated through integrated analyses of solution chemistry,mineralogy,and *** results showed a significant decrease in Na_(2)O content(>30 wt.%)of FGD gypsum-treated bauxite residue after 30 min of mechanical ball *** ball milling resulted in differentiation of the elemental distribution,modification of the minerals in crystalline structure,and promotion in the dissolution of alkaline minerals,thus enhancing the acid neutralization capacity of bauxite residue.5 wt.%FGD gypsum combined with 30 min mechanical ball milling was optimal for the dealkalization of bauxite residue.

关键词： bauxite residue alkalinity regulation flue gas desulfurization gypsum mechanical activation soil formation of bauxite residue

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基于异构网络面向多标签系统的推荐模型研究

软件学报 2017年第10期28卷 2611-2624页

作者：王瑜武延军吴敬征刘晓燕中国科学院软件研究所北京100190 中国科学院大学北京100049

标签成为信息组织的重要方式之一,随着推荐系统的蓬勃发展,标签推荐成为学者们研究的重要问题之一.目前存在各种各样的标签系统,其功能千差万别,标签数据信息越来越复杂.目前研究往往针对特定类型标签数据,缺乏既综合考虑标签数据中不... 详细信息

标签成为信息组织的重要方式之一,随着推荐系统的蓬勃发展,标签推荐成为学者们研究的重要问题之一.目前存在各种各样的标签系统,其功能千差万别,标签数据信息越来越复杂.目前研究往往针对特定类型标签数据,缺乏既综合考虑标签数据中不同类型对象的复杂信息又能适用于多种标签系统数据的标签推荐模型.构建了标签推荐模型Hn MTR,该模型首先针对标签数据中不同类型对象构建异构网络模型,其次对异构网络模型中不同类型顶点进行同空间映射,使不同类型的顶点和边可在同一空间进行量化比较;最后基于同空间映射后网络,引入多参数马尔可夫模型进行标签评分和推荐.通过基于豆瓣、Delicious和Meetup这3个标签系统数据实验,其结果表明,Hn MTR模型平均准确率比目前主流算法提高10%以上,取得了较好的推荐结果.

关键词：异构网络网络嵌入标签推荐标签系统周模型

Enhanced dealkalization of bauxite residue through calcium-activated desulfurization gypsum

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Transactions of Nonferrous Metals Society of China 2024年第10期34卷 3412-3424页

作者： yu-jun wu Sheng-guo XUE Li-ping LIU Feng LI Graeme J.MILLAR Fei GE Jiang TIAN College of Environment and Resources Xiangtan UniversityXiangtan 411105China School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Mechanical Medical and Process EngineeringFaculty of EngineeringQueensland University of TechnologyBrisbaneQueensland 4000Australia

A novel integrated approach to remove the free alkalis and stabilize solid-phase alkalinity by controlling the release of Ca from desulfurization gypsum was *** combination of recycled FeCl_(3)solution and EDTA activated desulfurization gypsum lowered the bauxite residue pH to ***,it also improved the residual Ca state,with its contribution to the total exchangeable cations increased(68%-92%).Notably,the slow release of exchangeable Ca introduced through modified desulfurization gypsum induced a phase transition of the alkaline *** treatment stabilized the dealkalization effect of bauxite residue via reducing its overall acid neutralization capacity in abating pH ***,this approach can provide guidance for effectively utilizing desulfurization gypsum to achieve stable regulation of alkalinity in bauxite residue.

关键词： bauxite residue desulfurization gypsum EDTA activation alkalinity regulation recycled FeCl_(3)

A Fuzzy Mathematics Based Fault Auto-diagnosis System for Vacuum Resin Shot Dosing Equipment

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International Journal of Plant Engineering and Management 2001年第4期6卷 170-178页

作者： HE Zheng wen, XU yu, wu jun School of Management, Xi’an Jiaotong University, Xi’an 710049, P.R.China School of Management Xian Jiaotong University

On the basis of the analysis of faults and their causes of vacuum resin shot dosing equipment, the fuzzy model of fault diagnosis for the equipment is constructed, and the fuzzy relationship matrix, the symptom fuzzy vector, the fuzzy compound arithmetic operator, and the diagnosis principle of the model are determined. Then the fault auto-diagnosis system for the equipment is designed , and the functions for real-time monitoring its operation condition and for fault auto diagosis are realized. Finally, the experiments of fault auto-diagnosis are conducted in practical production and the veracity of the system is verified.

关键词： fuzzy model fault auto diagnosis system vacuum resin shot dosing equipment

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二维纹理图象的产生

自动化学报 1989年第3期15卷 282-285页

作者：余军吴国威吴中权清华大学

本文在***提出的马尔可夫模型纹理综合方法的基础上,提出了一种级联的马尔可夫模型.利用此模型进行纹理图象综合时,可以克服文献[1]中所提出的方法的不稳定性,而且使模型应用范围更广泛,实验结果更理想.

关键词：级联纹理图象综合马尔可夫模型