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Parametric study on mass loss of penetrators

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Acta Mechanica Sinica 2010年第4期26卷 585-597页

作者： Li-ling he Xiao-Wei Chen Xiang he Department of Modem Mechanics University of Science and Technology of China 230027 Hefei China Institute of Structural Mechanics China Academy of Engineering Physics P.O. Box 919-401 621900 Mianyang China Luoyang Institute of Hydraulic Engineering Technology 471023 Luoyang China

Earth penetration weapon （EPW） is applicable for attacking underground targets protected by reinforced concrete and rocks. With increasing impact velocity, the mass loss/abrasion of penetrator increases, which significandy decreases the penetration efficiency due to the change of nose shape. The abrasion may induce instability of the penetrator, and lead to failure of its structure. A common disadvantage, i.e. dependence on corresponding experimen- tal results, exists in all the available formulae, which limits their ranges of application in estimating the mass loss of penetrator. In this paper, we conduct a parametric study on the mass loss of penetrator, and indicate that the mass loss of penetrator can be determined by seven variables, i.e., the initial impact velocity, initial nose shape, melting heat, shank diameter of projectile and density and strength of target as well as the aggregate hardness of target. Further discussion on factors dominant in the mass abrasion of penetrator are given, which may be helpful for optimizing the target or the projectile for defensive or offensive objectives, respectively.

关键词： Penetrator Mass loss Depth of penetration Parametric study

Interfacial Engineering of Polymer Blend with Janus Particle as Compatibilizer

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Chinese Journal of Polymer Science 2023年第4期41卷 500-515,I0005页

作者： Hai-ling he Fu-Xin Liang Institute of Polymer Science and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China

Mixing two or more polymers to produce the“polymer alloy”is one of the most versatile and economical strategies for developing new polymeric *** compatibility between polymer components largely determines the comprehensive performance of polymer *** recently,a type of unique surface partitioned materials,Janus particles,has been proposed to act as a novel interfacial compatibilizer for polymer *** Janus particles integrates the amphipathicity of diblock copolymer and interfacial stabilization of nanoparticles,displaying a significant superiority in comparison with molecular compatibilizers for a wide range of polymer *** this review,we mainly focus on the compatibilizing effects of Janus nanofillers of various morphologies,including spherical,snowman-like,and two-dimensional nanosheets,on polymer *** shed light on the impacts of compatibilization of Janus particles on phase morphologies,mechanical properties,and functionalities of polymer *** review could provide a guidance for designing an effective Janus particle compatibilizer to develop high-performance polymer blends.

关键词： Janus particles Compatibilizer Polymer blend Interfacial engineering

Deformation of amorphous azobenzene-containing polymer films induced by polarized light

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Acta Mechanica Sinica 2012年第4期28卷 1203-1208页

作者： ling-Hui he CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China 230026 HefeiChina

Photomechanical response of amorphous polymer films containing azobenzene chromophores in side chains is studied. By invoking the trans-cis isomerization mech- anism, the steady-state deformation of the film induced by uniform illumination of linearly polarized light is obtained analytically. The deformation turns out to be of entropic origin,produced to compensate the entropy decrease due to photo-induced redistribution of azobenzene chromophores normal to the polarization direction. The predicted elongation direction of the film is consistent with previous experimental observations.

关键词： Amorphous polymer. Azobenzene side-chain Photo-induced deformation

Study on alkali mechanical activation for recovering rare earth from waste fluorescent lamps

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Journal of Rare Earths 2018年第1期36卷 108-112页

作者： ling he Wen Ji Yanwei Yin Weimin Sun State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Recycling of rare earth from waste fluorescent lamps is becoming increasingly important in future sustainable development. However, cerium and terbium are usually difficult to recover due to the stable spinel structure. In the research, alkali mechanical activation was innovatively used to pretreat the waste phosphors for recovering rare earths. The effect of alkali mechanical activation on the structural changes of waste phosphors was explored using X-ray diffraction （XRD） and Fourier transform infrared spec- troscopy （FFIR）. Meanwhile, the effects of different parameters including milling speed, activation time, and amount of alkali on the leaching rates of rare earth were investigated. The rare earth elements re- covery rates are observed to increase rapidly, particularly with increases in rotational speed and acti- vation time. Under optimal conditions, the maximum leaching rates of Ce and Tb reach 85.0% and 89.8%, respectively. And the total recovery rates of rare earth reach 95.2%. All the results indicate that alkali mechanical activation can effectively destroy the spinel structure and produce substantial physico- chemical changes. These changes lead to the easy dissolution of rare earths in acid solution, and greatly improve the leaching of cerium and terbium.

关键词： Rare earthSpinel structureRecovery rateAlkali mechanical activationWaste phosphorsRare earths

基于问卷分析不同年级医学生中医全科医学教学的现状

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中国中医药现代远程教育 2025年第2期23卷 182-185页

作者：何玲颜娟赵鲲鹏甘肃中医药大学中医临床学院全科医学教研室甘肃兰州730000

目的调查分析中医院校不同年级学生对中医全科医学概论的学习需求及认知情况,以指导中医全科医学概论的教学改革,为培养更多优秀的全科医生做准备。方法针对本科不同年级医学生发放调查问卷,数据结果使用SPSS 27.0软件分析。结果各年级... 详细信息

目的调查分析中医院校不同年级学生对中医全科医学概论的学习需求及认知情况,以指导中医全科医学概论的教学改革,为培养更多优秀的全科医生做准备。方法针对本科不同年级医学生发放调查问卷,数据结果使用SPSS 27.0软件分析。结果各年级学生均对中医全科医学概论的学习保持较大兴趣82.46%(188/228);对全科医学信息来源方面,大五学生更倾向于作为未来就业方向去了解,且占比明显高于大一学生(P<0.05);对全科医学内容渴求方面,大一学生的学习需求明显高于大四和大五学生(P<0.05);学习主动性方面,大一学生对学习全科医学知识的积极性明显高于其他两个年级(P<0.05)。结论作为专业必修课,全科医学的课程设置、教学大纲和教材内容应与时俱进,适应我国社会发展需要,以本为本,学做一体,教学改革在路上。

关键词：中医全科医学概论教学学情分析调查问卷

Re-Os dating,and Pb-H-O isotope characteristics,of the Abra Cu-Ag-Pb-Au polymetallic deposit in Western Australia

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Acta Geochimica 2021年第5期40卷 739-751页

作者： Chaozhuang Xi Minghong Zheng ling he Haodong Xia School of Civil Engineering Hunan City UniversityYiyang 413000HunanChina Hunan Engineering Research Center of Structural Safety and Disaster Prevention for Urban Underground Infrastructure Yiyang 413000HunanChina Non-Ferrous Metals and Nuclear Industry Geological Exploration Bureau of Guizhou Guiyang 550005China Tianjin North China Geological Exploration Bureau Tianjin 300170China Ministry of Land and Resource Geological Information CentreYanjiao 065201China

The Abra deposit,a large lead-silver-copper–gold polymetallic deposit in Western Australia,is located at the eastern of the metallogenic belt of the Jillawarra basin in the Bangemall *** 4 th to the 6 th rock section of the Irrigully Group of Edmund Series are the principal ore-host strata,composed mainly of sandstone and fine *** orebody in Abra can be classified into two types as upper layer-like lead-silver and lower veins or netvein copper–*** metal minerals are mainly galena,chalcopyrite,and pyrite,while the gangue minerals are mainly quartz,dolomite,and *** ReOs isotopic age of the pyrite(1329.5±98 Ma)with the initial(187Os/188Os)=5.0±3.8 and Pb isotopic compositions(206 Pb/204 Pb=15.914–15.967,207Pb/204Pb=15.425–15.454,208Pb/204Pb=35.584–35.667)suggests that the metal minerals were sourced from the wall-rocks.d DV-SMOWvalues of quartz range from-35%to-17%whereas d18 OV-SMOWvalue range from 12%to 16%which indicates that the ore-forming fluids of Abra were mediumlow temperature and medium–low salinity,and were mainly metamorphic water and secondary atmospheric *** the medium–low temperature oreforming fluids are mixed with oxidizing reducing fluids carrying a large number of metal substances,a large number of ore-forming substances will be precipitated when the physical and chemical conditions change,thus it can be considered that the Abra deposit is a medium–low temperature hydrothermal polymetallic deposit.

关键词： Re-os isotope Pb–H-O isotope Abra cu-ag-pb-au polymetallic deposit Australia

GAMYB transcription factor LoMYB65 from lily plays a vital role in pollen development

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Horticultural Plant Journal 2024年第1期10卷 223-238页

作者： Xinyue Liu ling he Ze Wu Nianjun Teng Key Laboratory of Landscaping Agriculture Ministry of Agriculture and Rural AffairsCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Key Laboratory of Biology of Ornamental Plants in East China National Forestry and Grassland AdministrationCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Jiangsu Graduate Workstation of Nanjing Agricultural University and Nanjing Oriole Island Modern Agricultural Development Co. Ltd.NanjingJiangsu 210043China

Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination *** are many studies on pollen development in model plants,but few on flower crops such as ***(GA)is a large class of hormones and plays an important role in plant vegetative growth and reproductive *** is a group of the R2R3-MYB family upregulated by gibberellin,and plays an important role in anther ***,we isolated a novel GAMYB,named LoMYB65,from lily,which was closely related to the AtMYB65 and AtMYB33 in *** quantitative PCR results showed that LoMYB65 was mainly expressed in lily ***65 could be activated by 288μmol·L^(-1)GA3treatment and the LoMYB65 protein was located in the nucleus and cytoplasm,and had transactivation in yeast and tobacco leaf *** conserved motif within 226 amino acids of the C-terminal of LoMYB65 contributed to its *** of LoMYB65 caused dwarf phenotype,unnormal tapetum development,less seeds of siliques in transgenic Arabidopsis plants,the transgenic plants showed partly male ***,silencing of LoMYB65 with VIGS(Virus Induced Gene Silencing)in lily anthers caused unnormal pollen development and reduced the pollen *** of LoMYB65 in Arabidopsis and silencing of LoMYB65 in lily resulted in decreased pollen counts,so we speculate that LoMYB65 may be ***,these findings suggest that LoMYB65 may play an important role in anther development and pollen formation in ***65 may provide a useful candidate gene for pollenless breeding of lily.

关键词： Lily Anther development Pollen pollution GAMYB VIGS

One-step separation and recovery of rare earth and iron from NdFeB slurry via phosphoric acid leaching

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Journal of Rare Earths 2022年第2期40卷 338-344,I0006页

作者： ling he Qipeng Xu Wensheng Li Qizheng Dong Weimin Sun State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

The recovery of rare earth elements(REEs)from NdFeB slurry by traditional hydrometallurgy has been limited becuase a large number of REEs are lost during separation together with *** this paper,a simple and sustainable method is proposed to efficiently separate and recover REEs and iron from NdFeB *** were recovered by one-step selective precipitation in phosphoric acid,and the dissolved iron was recovered by oxalic *** acid leaching results show that under the conditions of 4 mol/L phosphoric acid,80℃,L/S of 30:1 and 90 min,the leaching efficiencies of Fe and REEs reach 98.76%and1.09%,*** the rest of REEs remained in the leaching residue in the form of REEPO_(4)·nH_(2)O *** mixed rare earth oxide(rare earth oxalate roasted at 800℃)and FeC_(2)O_(4)·2 H_(2)O are obtained by oxalic acid precipitation with purities of 99.49%and 97.17%from the REEPO4·nH_(2)O dissolving solution and the phosphoric acid leaching ***,the phosphoric acid is regenerated while recovering iron,and it can be reused in the phosphoric acid leaching step after removing the impurity C_(2)O_(4)^(2-).In summary,this work provides an efficient and environmentally friendly method for recovering REEs and iron from NdFeB slurry waste.

关键词： NdFeB slurry Phosphoric acid leaching Iron Rare earth elements Oxalic acid

On almost complex curves and Hopf hypersurfaces in the nearly Kahler six-sphere

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Science China Mathematics 2014年第5期57卷 1045-1056页

作者： he ling JIAO XiaoXiang ZHOU XianChao School of Mathematical Sciences University of Chinese Academy of Sciences School of Mathematical Sciences Fudan University

We study the almost complex curves and Hopf hypersurfaces in the nearly Khler S6(1),and their *** Hopf hypersurfaces,we give a classification theorem under some additional *** compact almost complex curves,we obtain... 详细信息

关键词： nearly Kahler structure Hopf hypersurface tubular hypersurface almost complex curve