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Defence Technology（防务技术） 2024年第1期31卷 230-241页

作者： junbao li Weibing li Xiaoming Wang ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing 210094China

This study proposed three types of Al—Hf reactive materials with particle size ratios(a),which were almost completely dense(porosity of<5.40%)owing to their preparation using hot-pressing *** characteristics and phas... 详细信息

This study proposed three types of Al—Hf reactive materials with particle size ratios(a),which were almost completely dense(porosity oflinearly with increasing strain rate.ε.It is found that the plastic deformation of the material increased with increasing strain *** a increased from 0.1 to 1,the flow stress gradually *** failure of the material was dominated by ductile fracture with a large Al phase plastic deformation band for lower a,while brittle fracture with crushed Hf particles occurred at higher ***,a constitutive model based on BP neural network was proposed to describe the stress-strain relationships of the materials,with an average relative error of 2.22%.

关键词： Reactive material Particle size Split Hopkinson pressure bar test Stressestrain relationship Impact failure BP neural network

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含调整器装药结构破片形成影响因素研究

南京理工大学学报 2024年第3期48卷 262-270页

作者：任冠群李伟兵徐赫阳李文彬李军宝南京理工大学智能弹药技术国防重点学科实验室江苏南京210094 上海航天电子技术研究所上海201109

为有效改善柱壳断裂位置并产生形状规则的大质量破片,该文设计了一种由柱壳装药以及嵌入其中的爆轰波调整器构成的新型破片战斗部结构,并研究了爆轰波调整器结构参数对破片输出的影响。采用AUTODYN-3D有限元计算软件,分析了爆轰波碰撞... 详细信息

为有效改善柱壳断裂位置并产生形状规则的大质量破片,该文设计了一种由柱壳装药以及嵌入其中的爆轰波调整器构成的新型破片战斗部结构,并研究了爆轰波调整器结构参数对破片输出的影响。采用AUTODYN-3D有限元计算软件,分析了爆轰波碰撞叠加切割柱壳形成破片的过程,找出了柱壳切割效果优良的调整器结构参数取值范围,并开展了最优结构的验证试验。研究结果表明:有效破片生成率随内外层装药厚度比、调整器厚度的增加以及沟槽数量的减小,由一定值逐渐达到100%;当内外层装药厚度比为5、调整器厚度为10 mm或15 mm且开有8或12个沟槽时,有效破片在生成率达到100%的同时兼具较大的平均质量;水井试验回收率为96.3%,获得的有效破片生成率为100%,破片平均长度和宽度分别为39.75 mm和14.2 mm,与仿真结果的误差分别为6.25%和11.25%。该文研究结果可为实现破片战斗部智能可选择化提供借鉴思路。

关键词：爆炸力学爆轰叠加壳体破碎规则破片不均匀加载

基于隐式退化模型的磁共振图像超分辨重建网络

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中国医学物理学杂志 2024年第6期41卷 690-701页

作者：刘环宇郭海鹏刘晓东李晗李君宝哈尔滨工业大学计算学部信息对抗技术研究所黑龙江哈尔滨150080 哈尔滨工业大学电子与信息工程学院自动化测试研究所黑龙江哈尔滨150080

对于使用算法提升磁共振(MR)图像分辨率的研究,现有方法多停留在跨尺寸、同尺寸有监督的超分辨算法研究,提出一种基于隐式退化映射模型的MR图像超分辨重建网络SG-Diffusion,通过掩码自编码器隐式建模MR图像的退化过程,减小实验构建数据... 详细信息

对于使用算法提升磁共振(MR)图像分辨率的研究,现有方法多停留在跨尺寸、同尺寸有监督的超分辨算法研究,提出一种基于隐式退化映射模型的MR图像超分辨重建网络SG-Diffusion,通过掩码自编码器隐式建模MR图像的退化过程,减小实验构建数据集与实际场景下MR图像的域差距,并基于隐式退化模型构建样本对,训练得到基于自引导扩散模型的MR图像重建网络,从而实现无监督同尺寸MR图像的空间分辨率提升。在fastMRI数据集的4倍加速采样脑部MR图像超分辨实验结果显示,本文提出的基于隐式退化模型的MR图像超分辨重建网络能够有效提升退化MR图像的空间分辨率,同时与基于显示退化模型的图像退化重建方法相比,本文提出的SG-Diffusion方法具有更好的重建效果。

关键词：脑部磁共振图像超分辨扩散模型

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旅大特稠油储层新型完井液体系的构建与评价

当代化工 2024年第4期53卷 921-924页

作者：徐涛李君宝李进贾立新张帅海洋石油高效开发国家重点实验室北京102209 中海石油(中国)有限公司天津分公司天津300459 中海油能源发展股份有限公司工程技术分公司天津300452

旅大A油田是一个埋藏浅、油质稠、储量大的典型重质特超稠油油藏,热采开发是其有效的开发方式。稠油油藏在储层物性、流体性质及开采工艺方面与常规油藏存在较大差异,现有常规水基完井液体系无法满足需求。针对该油田稠油热采工艺,充分... 详细信息

旅大A油田是一个埋藏浅、油质稠、储量大的典型重质特超稠油油藏,热采开发是其有效的开发方式。稠油油藏在储层物性、流体性质及开采工艺方面与常规油藏存在较大差异,现有常规水基完井液体系无法满足需求。针对该油田稠油热采工艺,充分考虑稠油油藏储层特性、稠油预防乳化增稠和降黏促排的新需求,开展新型完井液体系的构建。通过抑制性、降黏助排性、配伍性及热采高温环境下储层保护效果的评价,建立起适用于稠油的新型有机胺完井液体系。该体系在提升稠油热采井开发储层保护效果的同时,降低完井液综合成本,为渤海油田稠油开发提质增效提供有力保障。

关键词：完井液稠油油藏热采储层保护

Retraced longitudinal stacks low-frequency mosaic cylinder transducer

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Chinese Journal of Acoustics 2022年第2期41卷 143-153页

作者： Lü Kejia li junbao li Yuan Institute of Acoustics Chinese Academy of SciencesBeijing 100190 Beijing Engineering Technology Research Center of Ocean Acoustic Equipment Beijing 100190

A small-size low-frequency horizontal omni-directional cylinder transducer is *** is composed of four cylinder-shaped head mass blocks and four retraced piezoelectric ceramic longitudinal stacks sharing with one back mass *** transducer is analyzed and designed by using finite element method(FEM).A prototype is manufactured and *** results show that the maximum diameter of the transducer is 180 mm,the resonance frequency is 1.5 kHz,the maximum transmitting voltage response level is 131 dB and the maximum source level is above 188 dB,and the directivity of the transducer is horizontal *** transducer has the advantages of low frequency,small size and horizontal omni-directional,and has some good application prospects.

关键词： cylinder directional ceramic

Ferroelastic domain identification and toughening mechanism for yttrium tantalate–zirconium oxide

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Journal of Materials Science & Technology 2022年第32期127卷 78-88页

作者： Cheng Luo Cong li Ke Cao junbao li Junhui Luo Qinghua Zhang QianQian Zhou Fan Zhang lin Gu li Yang Yichun Zhou School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710126China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Engineering BIC-ESATPeking UniversityBeijing 100871China

Yttrium tantalate(YTaO_(4))is the next generation of higher service temperature thermal barrier coatings(TBCs)materials due to its smaller volume effect in phase change,lower thermal conductivity and unique ferroelastic domain ***,the low fracture toughness limits its *** first characterized the diffraction patterns of variants,and two variants(M_(1)and M_(2))observed in transmission electron microscopy(TEM)results were determined from four possible variants by mechanical *** role of Zr^(4+)doping in ferroelastic toughening was explained in *** the increase of Zr^(4+)doping concentration,the monoclinic angle β and the domain rotation angleαdecrease,*** spontaneous strain component and the principal strain in the main space also have a similar decreasing *** decrease of the ferroelastic domain inversion energy barrier is beneficial to the improvement of fracture *** the results of Vickers indentation,we found that Zr^(4+)could be enriched at the domain boundary to inhibit the generation of *** appropriate amount of Zr^(4+)is conducive to the improvement of fracture toughness,and the excessive Zr^(4+)will reduce the fracture toughness due to the generation of by-product t-ZrO_(2).So,the optimal composition is Y_(0.44)Ta_(0.44)Zr_(0.12)O_(2) and the best fracture toughness(2.9–3.8MPa m^(1/2))is equivalent to the commercial *** result will promote the application of a new generation of TBCs.

关键词： Ferroelastic domain Variants Domain switch TBCs Fracture toughness

18个甜玉米品种的产量及其构成因素的灰色关联度分析

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中国种业 2024年第1期 77-81,87页

作者：陈荣丽李君保周彦民易红华重庆市农业科学院重庆401329 酉阳土家族苗族自治县农业技术推广站重庆409899 重庆科光种苗有限公司重庆400060

为探明鲜食甜玉米品种的主要农艺性状对产量的影响程度,用灰色关联度的分析方法,对18个甜玉米品种的主要农艺性状及产量进行关联分析。结果表明,18个甜玉米品种出苗—采收天数为79~88d,株高为185~285cm,穗位高为55~130cm,穗长为16.0~20.... 详细信息

为探明鲜食甜玉米品种的主要农艺性状对产量的影响程度,用灰色关联度的分析方法,对18个甜玉米品种的主要农艺性状及产量进行关联分析。结果表明,18个甜玉米品种出苗—采收天数为79~88d,株高为185~285cm,穗位高为55~130cm,穗长为16.0~20.8cm,穗粗为4.7~5.1cm,秃尖长为0.2~5.5cm,穗行数为13.6~17.6行,行粒数为21.4~40.4粒,百粒重为23.3~43.3g,出籽率为51.8%~60.8%,产量为9036.0~14919.0kg/hm^(2);18个甜玉米品种主要农艺性状与产量的关联度由大到小依次为:穗长>行粒数>穗粗>株高>出苗—采收天数>穗位高>百粒重>出籽率>穗行数>秃尖长;穗长是影响甜玉米产量的主要因素,其次是行粒数、穗粗,秃尖长对产量影响相对较小。表明在重庆地区要选育出高产甜玉米杂交品种,应在育种中着重考虑穗长、行粒数和穗粗3个性状的选择。

关键词：甜玉米品种产量农艺性状灰色关联度分析

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东非黑白疣猴的人工育幼

黑龙江动物繁殖 2024年第1期32卷 52-55页

作者：李俊保关洪敏潘震震邢广生田澍辽郑州市动物园郑州450008 郑州城建职业学院郑州451200

东非黑白疣猴(Colobus guereza)栖息于热带丛林或接近草原的树林中。郑州市动物园于2017年引进6只东非黑白疣猴并饲养于珍猴馆。文章对郑州市动物园一例人工育幼成功的东非黑白疣猴育幼过程进行了总结分析。东非黑白疣猴出生后,在初始温... 详细信息

东非黑白疣猴(Colobus guereza)栖息于热带丛林或接近草原的树林中。郑州市动物园于2017年引进6只东非黑白疣猴并饲养于珍猴馆。文章对郑州市动物园一例人工育幼成功的东非黑白疣猴育幼过程进行了总结分析。东非黑白疣猴出生后,在初始温度30℃、相对湿度48%~60%条件下用奶粉配制人工乳并适当添加微量元素和矿物质,对幼猴进行喂哺,每天喂奶6~8次。随着日龄增加,逐渐减少喂奶次数,并将温度降低至25℃。90日龄时通过投喂碾碎的新鲜榆树叶促使其过渡到采食高纤维素食物;150日龄时,在每天天气晴朗、温度适宜时段外放1 h,并逐渐增加外放时间,使疣猴能接受到阳光照射并适应外部环境;至180日龄时,疣猴生长发育良好。

关键词：东非黑白疣猴人工育幼温度湿度奶粉树叶

Object use in insects

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Insect Science 2024年第4期31卷 1001-1014页

作者： Chao Wen Cai Wang Xiaoli Guo Hongyu li Haijun Xiao junbao Wen Shikui Dong School of Grassland Science Beijing Forestry UniversityBeijingChina College of Forestry and Landscape Architecture South China Agricultural UniversityGuangzhouChina Beijing Key Laboratory for Forest Pest Control Beijing Forestry UniversityBeijingChina

Insects are the most diverse group of organisms in the animal kingdom,and some species exhibit complex social *** research on insect object use is still in its early stages,insects have already been shown to display rich object-use *** review focuses on patterns and behavioral flexibility in insect object-use behavior,and the role of cultural evolution in the development of object-use *** use in insects is not widespread but has been documented in a diverse set of *** insects can use objects flexibly and display various object-use *** mammals and birds,insects use objects in diverse activities,including foraging,predator defense,courtship,and ***,pre-existing manipulative behaviors,and anatomical structure affect innovations in object *** addition,learning and imitation are the main mechanisms underlying the spread of object-use behaviors within *** that insects are one of the major animal groups engaging in object use,studies of insect object use could provide general insights into object use in the animal kingdom.

关键词： cognition evolution insects learning object use

RuO_(2)/TiO_(2)/MXene with multi-heterojunctions coating on carbon cloth for high-activity chlorine evolution reaction at large current densities

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Nano Research 2024年第6期17卷 4764-4772页

作者： Yuhao Duan liuxu Wei Chenyu Cai junbao Mi Fuyuan Cao Jiaze Chen Xiaolong li Xiujiang Pang Bin li Lei Wang Key Laboratory of Eco-chemical Engineering Ministry of EducationInternational Science and Technology Cooperation Base of Eco-chemical Engineering and Green ManufacturingCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China College of Environment and Safety Engineering Qingdao University of Science and TechnologyQingdao 266042China

The chlorine evolution reaction(CER)is a crucial step in the production of chlorine gas and active chlorine by chlor-alkali ***,the endeavor to fabricate electrodes capable of yielding high current density at minimal overpotential remains a central challenge in advancing the realm of chlorine evolution ***,we grow TiO_(2)and RuO_(2)on MXene@carbon cloth(CC)through the favorable affinity and induced deposition effect between the surface functional groups of MXene and the metal.A self-supported electrode(RuTiO_(2)/MXene@CC)with strong binding at the electrocatalyst-support interface and weak adhesion at electrocatalyst-bubble interface is *** RuTiO_(2)/MXene@CC can reduce the electron density of RuO_(2)by regulating the electron redistribution at the heterogeneous interface,thus enhancing the adsorption of Cl−.RuTiO_(2)/MXene@CC could achieve a high current density of 1000 mA·cm^(−2)at a small overpotential of 220 mV,superior to commercial dimensionally stable anodes(DSA).This study provides a new strategy for constructing efficient CER catalysts at high current density.

关键词： chlorine evolution reaction high current density MXene TiO_(2) RuO_(2)