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固体发动机药柱低温点火开裂失效的跨尺度分析

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含能材料 2024年第2期32卷 142-151页

作者：王贵军周涛吴艳青侯晓黄风雷北京理工大学爆炸科学与技术国家重点试验室北京100081 中国航天科技集团第四研究院西安航天化学动力有限公司陕西西安710025 北京理工大学宇航学院北京100081

为了准确预测推进剂装药在低温点火过程中是否发生开裂,提出了一种全局⁃局部单向收缩耦合的跨尺度分析方法。针对高能硝酸酯增塑聚醚(NEPE)推进剂,开展低温中应变率单轴拉伸试验,获取了推进剂的典型失效模式。结果表明,基于发展的推进... 详细信息

为了准确预测推进剂装药在低温点火过程中是否发生开裂,提出了一种全局⁃局部单向收缩耦合的跨尺度分析方法。针对高能硝酸酯增塑聚醚(NEPE)推进剂,开展低温中应变率单轴拉伸试验,获取了推进剂的典型失效模式。结果表明,基于发展的推进剂非线性粘弹性本构模型,实现了固体发动机药柱低温点火的宏观结构分析,获取了推进剂药柱结构危险点的位置;同时建立了考虑颗粒与基体界面脱湿和颗粒断裂的细观颗粒填充模型,进一步将宏观结构分析结果作用于相应的细观代表性体积单元(RVE)上。最后,建立推进剂细观失效准则,表明在低温点火条件下药柱结构完整性满足要求。收缩跨尺度分析方法可作为预测药柱在低温点火过程中开裂行为的有效手段。

关键词：硝酸酯增塑聚醚(NEPE)推进剂低温点火跨尺度分析颗粒与基体界面脱湿药柱开裂

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浙江庆元发现半叶趾虎属蜥蜴

动物学杂志 2024年第3期59卷 418-428页

作者：朱滨清高朔郭伟波吴延庆吴军生态环境部南京环境科学研究所南京210042

2022年11月在浙江省庆元县贤良镇采集到10只半叶趾虎属(Hemiphyllodactylus)蜥蜴,经形态比对和分子系统分析鉴定为香港半叶趾虎(***),为浙江省爬行动物分布新记录种。标本体型较小,头体长大于尾长,颏鳞5或6枚,背鳞13~15行,腹鳞9或10行,... 详细信息

2022年11月在浙江省庆元县贤良镇采集到10只半叶趾虎属(Hemiphyllodactylus)蜥蜴,经形态比对和分子系统分析鉴定为香港半叶趾虎(***),为浙江省爬行动物分布新记录种。标本体型较小,头体长大于尾长,颏鳞5或6枚,背鳞13~15行,腹鳞9或10行,第II-V指、趾扩展部攀瓣式分别为3(4)-4-4-4、3(4)-4(5)-4(5)-4(5),雄性具连续的肛前孔和股孔24或25个。浙江庆元的标本在形态特征上与香港半叶趾虎地模标本基本一致。基于线粒体ND2基因进行贝叶斯系统发育分析,浙江庆元的标本与香港半叶趾虎地模标本的序列聚成单系支,支持率达0.99,并且两者间的未校正遗传距离仅为1.6%~1.7%,确定浙江庆元的标本为香港半叶趾虎。这是半叶趾虎属在浙江省的首次记录,说明该属物种可能有更大的分布范围。

关键词：半叶趾虎属浙江省庆元县新记录属

1-quasiconformal mappings on a (2,2)-type quadric

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Applied Mathematics(A Journal of Chinese Universities) 2009年第1期24卷 65-75页

作者： wu qing-yan Dept. of Math. Zhejiang Univ. Hangzhou 310027 China

This paper gets the Beltrami equations satisfied by a 1-quasiconformal mapping, which are exactly CR or anti-CR equations on （2,2）-type quadric Q0. This means a 1-quasiconformal mapping on Q0 is CR or anti-CR. This reduces the determination of 1- quasiconformal mappings to a problem on the theory of several complex analysis. The result about the group of CR automorphisms is used to determine the unit component of group of 1-quasiconformal mappings.

关键词： Beltrami equation quasiconformal mapping quadric CR automorphism

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网络交易的东方蝾螈遗传多样性及其溯源分析

生态与农村环境学报 2024年第9期40卷 1222-1229页

作者：梁一诺刘畅唐一菁吴延庆南京警察学院江苏南京210046 野生动植物物证技术国家林业和草原局重点实验室江苏南京210046 生态环境部南京环境科学研究所江苏南京210018

随着网络经济和物流产业的发展,越来越多的两栖动物作为异宠出现在网络交易平台,网络贸易已然成为野生动物非法交易的重灾区。以网络交易平台上的东方蝾螈(Cynops orientalis)为对象,对中国5个不同地区(广西、广东、河南、辽宁和山东)... 详细信息

随着网络经济和物流产业的发展,越来越多的两栖动物作为异宠出现在网络交易平台,网络贸易已然成为野生动物非法交易的重灾区。以网络交易平台上的东方蝾螈(Cynops orientalis)为对象,对中国5个不同地区(广西、广东、河南、辽宁和山东)的种群进行遗传多样性分析,探究网络交易平台上东方蝾螈的遗传多样性,并结合已公布的基因序列信息对其原产地进行溯源分析。结果表明,来自不同货源地的养殖种群均具有较高遗传多样性(单倍型多样性大于0.95)。值得注意的是,网络交易平台上的部分东方蝾螈来自安徽、浙江的野生种群。针对东方蝾螈开发了基于线粒体DNA的分子溯源技术,为网络野生动物交易管理提供了有效的技术手段,并就规范野生动物网络交易提出对策建议。

关键词：网络贸易遗传多样性溯源东方蝾螈

On fundamental solution for powers of the sub-Laplacian on the Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2017年第3期32卷 365-378页

作者： WANG Hai-meng wu qing-yan School of Mathematics and Information Technology Jiangsu Second Normal University School of Science Linyi University

We discuss the fundamental solution for m-th powers of the sub-Laplacian on the Heisenberg group. We use the representation theory of the Heisenberg group to analyze the associated m-th powers of the sub-Laplacian and to construct its fundamental solution. Besides, the series representation of the fundamental solution for square of the sub-Laplacian on the Heisenberg group is given and we also get the closed form of the fundamental solution for square of the sub-Laplacian on the Heisenberg group with dimension n = 2, 3, 4.

关键词： sub-Laplacian fundamental solution group Fourier transform Plancherel formula Heisenberg group

考虑细观损伤的推进剂粘弹性多尺度本构模型研究

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含能材料 2024年第2期32卷 133-141页

作者：乌布力艾散·麦麦提图尔荪周涛吴艳青侯晓周程哲北京理工大学爆炸科学与技术国家重点实验室北京100081 中国航天科技集团第四研究院西安航天化学动力有限公司陕西西安710025 北京理工大学宇航学院北京100081

为了深入研究固体推进剂细观损伤行为及对其宏观力学性能的影响,在223~333 K温度下对硝酸酯增塑聚醚推进剂(NEPE)推进剂开展了单轴拉伸和应力松弛试验,获得了相应的应力应变曲线及松弛模量主曲线。在有限变形下开发了考虑细观损伤的非... 详细信息

为了深入研究固体推进剂细观损伤行为及对其宏观力学性能的影响,在223~333 K温度下对硝酸酯增塑聚醚推进剂(NEPE)推进剂开展了单轴拉伸和应力松弛试验,获得了相应的应力应变曲线及松弛模量主曲线。在有限变形下开发了考虑细观损伤的非线性粘弹性本构模型,该模型通过将微空洞演化与温度、应变率、围压及循环加载损伤等因素关联实现对推进剂力学性能的多尺度分析。通过有限元软件ABAQUS对模型进行了二次开发,并基于试验数据确定了模型参数,之后将模型应用于预测推进剂在不同加载下的力学响应。结果表明,该模型能够准确预测推进剂在宽温(223~333 K)和加载速率(1~200 mm·min^(-1))下的单轴拉伸响应,并且适用于循环加载、围压试验和双轴加载试验,验证了该模型在复杂应力状态下的有效性。该模型所需参数较少且易于嵌入商用软件,可为发动机推装药结构完整性的多尺度分析提供一定的理论指导。

关键词：固体推进剂细观损伤多尺度本构模型非线性粘弹性围压双轴拉伸

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绿鳍马面鲀中轴骨骼早期发育规律

动物学杂志 2024年第4期59卷 597-606页

作者：朱金超边力李凤辉吴丹陈莹秦搏杨立国吴艳庆英娜陈四清中国水产科学研究院黄海水产研究所海水养殖生物育种与可持续产出全国重点实验室青岛266071 青岛海洋科技中心海洋渔业科学与食物产出过程功能实验室青岛266237 上海海洋大学水产与生命学院上海201306 中国水产科学研究院东海水产研究所上海201306

运用阿新利蓝-茜素红双染色技术研究绿鳍马面鲀(Thamnaconus septentrionalis)初孵仔鱼和1~60 dah(孵出后日龄)仔、稚和早期幼鱼中轴骨骼(头骨和脊柱)的发育规律。结果表明:绿鳍马面鲀初孵仔鱼头部无明显骨骼元件,3 dah脑颅软骨元件有... 详细信息

运用阿新利蓝-茜素红双染色技术研究绿鳍马面鲀(Thamnaconus septentrionalis)初孵仔鱼和1~60 dah(孵出后日龄)仔、稚和早期幼鱼中轴骨骼(头骨和脊柱)的发育规律。结果表明:绿鳍马面鲀初孵仔鱼头部无明显骨骼元件,3 dah脑颅软骨元件有前索软骨、侧索软骨、筛板和耳软骨环,咽颅软骨元件有米克尔氏软骨、腭方软骨、角鳃软骨和基鳃软骨;8 dah脑颅耳软骨环愈合成圆,咽颅上颌骨两侧末端与腭方软骨相连,角鳃软骨从前往后逐渐变短;15 dah脑颅耳软骨环凸出,咽颅齿骨和续骨出现,鳃丝密集分布,头部骨骼框架趋于稳定;18 dah脑颅嗅软骨环出现,咽颅米克尔氏软骨发生退化,下舌骨和上舌骨出现,上下颌前端出现锥形齿;20 dah脑颅出现额骨和筛骨,咽颅上下颌下移,前鳃盖骨和前颌骨出现并硬骨化;22 dah咽颅前鳃盖骨向下延伸出骨片,7对鳃条骨硬骨化;24 dah顶骨、副蝶骨、下鳃盖骨、主鳃盖骨和角舌骨出现并硬骨化;26 dah头部布满硬骨化的锥形小鳞;33 dah脑颅额骨、筛骨和缘带完全硬骨化,吻端变长,咽颅下鳃盖骨和主鳃盖骨完全硬骨化,锥形齿变门齿状;50 dah头部除鳃丝其余骨骼均完全硬骨化,可认为头部骨骼硬骨化完成。绿鳍马面鲀的脊柱14 dah前透明无色;18 dah尾端的髓弓和脉弓分化出现;25 dah椎体分节完成;28 dah椎体硬骨化完成;30 dah部分椎体的后关节突与髓弓相愈合;45 dah各椎体间间距缩短,脊柱完全硬骨化。研究理清了绿鳍马面鲀早期发育过程中轴骨骼元件的发育时序和骨化特征,初步阐释了其中轴骨骼的生长发育规律和特殊性,可为此物种苗种培育提供参考。

关键词：绿鳍马面鲀阿新利蓝-茜素红染色仔鱼稚鱼中轴骨骼

Comparative analysis of flower-meristem-identity gene APETALA2 (AP2) codon in different plant species

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Journal of Integrative Agriculture 2018年第4期17卷 867-877页

作者： wu yan-qing LI Zhi-yuan ZHAO Da-qiu TAO Jun College of Animal Science and Technology Yangzhou University Yangzhou 225009 P.R. China Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/College of Horticulture and Plant Protection Yangzhou University Yangzhou 225009 P.R. China

The flower-meristem-identity gene APETALA2(AP2), one of class-A genes, is involved in the establishment of the floral meristem and the forming of sepals and petals. Codon usage bias(CUB) identifies differences among species, meanwhile dynamic analysis of base composition can identify the molecular mechanisms and evolutionary relationships of a specific gene. In this study, eight coding sequences(CDS) of AP2 gene were selected from different plant species using the Gen Bank database. Their nucleotide composition(GC content), genetic index, relative synonymous codon usage(RSCU) and relative codon usage bias(RCUB) were calculated with R Software to compare codon bias and base composition dynamics of AP2 gene codon usage patterns in different plant species. The results showed that the usage of AP2 gene codons from different plant species were influened by GC bias, especially GC3 s. Overall, base composition analysis indicated that the usage frequency of codon AT in the gene coding sequence was higher than GC among AP2 gene CDS from different plant species. Furthermore, most AP2 gene CDSs ended with AT; AGA, GCU and UGU had relatively high RSCU values as the most dominant codon; the usage characteristic of the AP2 gene codon in Malus domestica was similar to that of Vitis vinifera; Paeonia lactiflora was similar to Paeonia suffruticosa and Solanum lycopersicum was similar to Petunia×hybrida. There was a moderate preference in the usage of AP2 gene codon among different plant species from relatively low frequency of optimal codon(Fop) values and high effective number of codons(ENC) value. This study has revealed the usage characteristics of the AP2 gene codon from the comparision of AP2 gene codon preference and base dynamics in different plant species and provide a platform for further study towards transgenic engineering and codon optimization.

关键词： APETALA2(AP2) species codon usage bias(CUB) base composition dynamics

Flavonoid content and expression analysis of flavonoid biosynthetic genes in herbaceous peony(Paeonia lactiflora Pall.)with double colors

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Journal of Integrative Agriculture 2016年第9期15卷 2023-2031页

作者： wu yan-qing WEI Meng-ran ZHAO Da-qiu TAO Jun Jiangsu Key Laboratory of Crop Genetics and Physiology/College of Horticulture and Plant Protection Yangzhou University Yangzhou 225009 P.R. China Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement Nanjing 210014 P.R. China

Herbaceous peony（Paeonia lactiflora Pall.） is a famous flower with medicinal values, and its flowers have a number of medicinal constituents, especially flavonoids. In this study, a P. lactiflora cultivar with double colors including white outer-petal and yellow inner-petal was used as the experimental materials to perform the qualitative and quantitative analysis of flavonoids by high-performance liquid chromatograph-electrospray ionization-mass spectrometry（HPLC-ESI-MSn） and investigate the expression patterns of flavonoid biosynthetic genes using real-time quantitative polymerase chain reaction（Q-PCR）. The results showed that the colors of both petals gradually weakened with flower development. Moreover, one main anthocyanin composition（peonidin 3,5-di-O-glucoside） and five main anthoxanthin compositions（kaempferol di-hexoside, kaempferol-3-O-malonylglucoside-7-O-glucoside, quercetin-3-O-galactoside, luteolin-7-O-glucoside and isorhamnetin-3-O-glucoside） were found in the both, differing significantly in their peak areas only. Total anthocyanin, anthoxanthin and flavonoid contents in white outer-petal and yellow inner-petal gradually decreased during flower development, and were consistently higher in white outer-petal. Furthermore, the expression patterns of nine structural genes in P. lactiflora flavonoid biosynthetic pathway showed that the expression levels of phenylalanine ammonialyase gene（Pl PAL）, chalcone synthase gene（PlC HS）, flavanone 3-hydroxylase gene（PlF 3H）, anthocyanidin synthase gene（PlA NS） and UDP-glucoside： flavonoid 5-O-glucosyltransferase gene（Pl F5GT） in two petals basically presented declined tendencies, and transcription levels of Pl PAL, Pl CHS, Pl ANS, Pl F3 GT and Pl F5 GT also tended to be higher in white outer-petal, which was correlated with their flavonoid contents. These results would lay a solid foundation for the exploration and utilization of flavonoid resources in P. lactiflora flowers.

关键词： herbaceous peony flower color flavonoids gene expression