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Phylogenetic relationship of Podocopida (Ostracoda: Podocopa) based on 18S ribosomal DNA sequences

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Acta Oceanologica Sinica 2006年第2期25卷 99-108页

作者： YU Na zhao meiying CHEN Liqiao YANG Pin School of Life Science East China Normal UniversityShanghai 200062China

Nucleotide sequences from 18S rDNA of 11 ostracodes, which represent four suborders and six superfamilies of podocopidan, were determined. The phylogenetic relationships were analyzed based on three kinds of methods (maximum-likelihood, maximum-parsimony, and neighbor-joining), and the three topologies gained were basically similar. The results have showed that (1) a monophyletic Podocopida was supported strongly; (2) the phylogenetic relationships of four suborders were (Darwinulocopina plus (Bairdiocopina plus (Cytherocopina plus Cypridocopina))), which indicated that a close relationship between Cytherocopina and Cypridocopina, and Darwinulocopina had separated early from the main podocopinan; (3) Cypridocopinan formed a monophyletic group, among which the phylogenetic relationship of three superfamilies was (Cypridoidea plus (Macrocypridoidea plus Pontocypridoidea)).

关键词： 18S rDNA nuclear gene molecular phylogeny Podocopida Ostracoda

Broadband absorption performance of 3D-printed polyetheretherketone-based electromagnetic wave-absorbing composites

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Chinese Journal of Aeronautics 2024年第8期37卷 547-558页

作者： Lin BAI Nan CHANG meiying zhao Chi HOU Yi CAO Dichen LI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Chengdu Aircraft Design and Research Institute Chengdu 610091China Xi’an Key Laboratory of Advanced Structure Design and Application of Aircraft Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710054China

The rapid development of additive manufacturing technology has offered a new avenue for designing and fabricating high wave-absorbing meta *** this study,the mechanical properties and broadband absorption performance of Poly-Ether-Ether-Ketone(PEEK)–based electromagnetic wave–absorbing composite materials was *** high-performance polymer PEEK was used as the matrix,and the materials with electromagnetic wave loss,such as reduced graphene oxide,Carbonyl Iron(CI),and Flake CI(FCI),were used as *** on the theory of impedance matching,a wave-absorbing structure with a gradual impedance gradient was designed and *** test results showed that at the 2.0–18.0 GHz frequency band,the coverage rate of the effective absorption bandwidth was up to 72.0%,the average optimal reflectivity was–18.09 dB,and the wide-angle absorption range was 0°–30°.The advantages of additive manufacturing technology in designing and fabricating wave-absorbing structures are presented,demonstrating that the technology is an effective method for creating broadband absorbing structures.

关键词： Absorption performance Additive manufacturing Electromagnetic absorption PEEK composite materials Gradual structure Broadband absorption

The effect of military training on anxiety symptoms in Chinese recruits

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重庆医学 2012年第36期41卷 3814-3816,3819页

作者： Li Hongzheng Lei meiying zhao Donghai zhao Liqiong Ye Changqing Zhou Hongkui Liu Gen Qin Mei Li Jiefeng Wen Jian Huang Pinde Mental Health Center 303 Hospital of PLA Nanning Guangxi 530021 China

Objective To investigate the prevalence of anxiety symptoms in army recruits and the effect of military training on *** A cluster sampling of 1431 new army recruits was *** anxiety level of recruits was determined by Beck Anxiety Inventory(BAI) and Adult EPQ questionnaires prior to,one month after,and two months after entering basic military *** compiled biographic variables of the recruits were collected before the *** The highest BAI score(32.71±7.87) was observed 2 days before training,followed by 1 month after training(31.49±7.75) and 2 months after training(29.87±6.95).BAI score before training correlated with neuroticism and extraversion of recruits,the psychological trauma,suicide feeling and frequency of exercise before recruiting.A significant decrease in the percentage of severe symptom of wobbliness in legs,instability to relax,racing heart,dizziness,fear of the worst happening and trembling hands was observed after 1 month and/or 2 months of military *** A higher BAI score and percentage of severe anxiety symptoms were observed before the training which correlated with psychological characteristics of recruits as well as the psychological experience before entering training.A combination of early psychological interference and physical exercise could reduce the anxiety.

关键词：英文摘要编辑工作学术论文重庆医疗

Genetic analysis on 3'- terminal flanking region of uncoupling protein 3 in different pig breeds

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Chinese Science Bulletin 2002年第18期47卷 1541-1543页

作者： FANG meiying, zhao Xingbo, LI Ning & WU ChangxinCollege of Animal Science and Technology, China Agricultural University, Beijing 100094, China State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, China College of Animal Science and Technology China Agricultural University Beijing China State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China

The 3’-terminal flanking region of porcine uncoupling protein 3 (UCP3) was cloned, the sequence data revealed 15 nucleotide substitutions among Landrace and three Chinese native pig breeds named Neijiang, Minpig and Erhualian. The continuous 9 polymorphic sites were checked by PCR-RFLP, the results indicated that Erhualian had extraordinary gene frequency, presented most significant difference by x2 test compared with Landrace, Largewhite, Neijiang and Minpig respectively, significant level compared with Meishan; and Meishan also had significant difference compared with Landrace and Minpig respectively. These results can be concluded that Taihu pigs have special genetic characteristics among pig breeds.

关键词： pig uncoupling protein gene clone PCR-RFLP.

复合材料层合板结构固化过程数值分析方法研究

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西北工业大学学报 2015年第6期33卷 900-905页

作者：彭亮毛伟赵美英西北工业大学航空学院陕西西安710072

为了研究复合材料层板结构在固化过程中的温度场与固化度场分布情况,对ABAQUS子程序进行了二次开发,构建了不同固化动力学方程的子程序模块,实现了层合板固化过程的三维数值模拟。通过算例验证,所建立的数值分析方法能精确求解固化过程... 详细信息

为了研究复合材料层板结构在固化过程中的温度场与固化度场分布情况,对ABAQUS子程序进行了二次开发,构建了不同固化动力学方程的子程序模块,实现了层合板固化过程的三维数值模拟。通过算例验证,所建立的数值分析方法能精确求解固化过程中的温度场和固化度场。基于该方法,进一步讨论了层合板边界条件、厚度、升温速率对温度场和固化度场的影响。上述研究方法具有较强的适用性,对改善固化工艺参数,控制结构固化变形具有一定的指导意义。

关键词：固化过程边界条件 ABAQUS 有限元法

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基于杂交算法的机翼结构布局优化设计

西北工业大学学报 2007年第1期25卷 46-50页

作者：王伟赵美英常楠西北工业大学航空学院陕西西安710072

为了解决机翼结构布局优化问题,提出一种同时进行拓扑优化、形状优化及几何尺寸优化的杂交优化算法。对拓扑设计变量和形状设计变量采用混合编码方式构造染色体结构,利用MSC/NASTRAN实现尺寸优化,并将其结果作为布局遗传操作的依据,利... 详细信息

为了解决机翼结构布局优化问题,提出一种同时进行拓扑优化、形状优化及几何尺寸优化的杂交优化算法。对拓扑设计变量和形状设计变量采用混合编码方式构造染色体结构,利用MSC/NASTRAN实现尺寸优化,并将其结果作为布局遗传操作的依据,利用混合编码遗传算法进行布局优化。为了加快收敛进程,利用专家知识的启发性功能对布局设计区域进行了有效缩减,以产生符合工程实际要求的布局形式。通过对大展弦比机翼结构的布局优化设计计算,表明文中所提结构布局优化方法减重效果明显,是可行和有效的。

关键词：杂交算法混合编码遗传算法布局优化专家知识 MSC/NASTRAN

大展弦比飞翼结构拓扑、形状与尺寸综合优化设计

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机械强度 2008年第4期30卷 596-600页

作者：王伟杨伟赵美英西北工业大学航空学院西安710072

为解决机翼结构布局优化设计问题,提出一种两级三层优化设计方法。第一级采用拓扑优化手段得到翼梁的大致位置与数目,将基于RAMP插值模型的变密度法与NASTRAN的有限元分析功能相结合,对机翼结构进行拓扑优化设计;第二级在第一级优化的... 详细信息

为解决机翼结构布局优化设计问题,提出一种两级三层优化设计方法。第一级采用拓扑优化手段得到翼梁的大致位置与数目,将基于RAMP插值模型的变密度法与NASTRAN的有限元分析功能相结合,对机翼结构进行拓扑优化设计;第二级在第一级优化的基础上进行形状优化和尺寸优化的综合优化设计,将复合形法与NASTRAN改进的可行方向法相结合,分别优化翼梁的位置和机翼各元件尺寸,最终完成机翼结构的布局优化设计。通过对大展弦比飞翼结构优化说明,文中所提的两级三层优化方法是可行和有效的,有着很好的推广应用价值。

关键词：大展弦比拓扑优化形状优化尺寸优化

基于复合材料层板稳定性的铺层参数优化设计方法

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机械强度 2008年第1期30卷 148-151页

作者：常楠杨伟王伟赵美英西北工业大学航空学院西安710072

提出一种基于复合材料层板稳定性的铺层参数优化设计方法,首先利用最大应变能准则优化分层厚度,利用库塔条件推导出层合板单元厚度迭代公式优化单元厚度,两步交替进行,完成层板厚度与铺层比例优化;在此基础上采用遗传算法优化层合板铺... 详细信息

提出一种基于复合材料层板稳定性的铺层参数优化设计方法,首先利用最大应变能准则优化分层厚度,利用库塔条件推导出层合板单元厚度迭代公式优化单元厚度,两步交替进行,完成层板厚度与铺层比例优化;在此基础上采用遗传算法优化层合板铺层顺序,最终设计出满足稳定性要求的最佳层合板铺层。通过算例分析表明,文中方法与传统方法相比收敛速度明显提高。同时,最佳的厚度分布也为层合板加筋设计提供理论参考。

关键词：复合材料层合板稳定性优化设计加筋设计

金属多层隔热结构反射屏热阻对传热性能影响数值分析

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西北工业大学学报 2009年第3期27卷 310-315页

作者：万小朋侯赤赵美英西北工业大学航空学院陕西西安710072

针对金属多层隔热结构中反射屏的附加辐射热阻、反射屏与纤维层的接触热阻对热传导性能的影响展开数值分析,首先基于有限容积法和二热流法建立了离散化的系统热传导方程组,然后分析计算了反射屏在瞬态和稳态热传导过程中对辐射热流的抑... 详细信息

针对金属多层隔热结构中反射屏的附加辐射热阻、反射屏与纤维层的接触热阻对热传导性能的影响展开数值分析,首先基于有限容积法和二热流法建立了离散化的系统热传导方程组,然后分析计算了反射屏在瞬态和稳态热传导过程中对辐射热流的抑制以及等效的附加辐射热阻;最后结合多点接触热阻分析理论,推导了反射屏与纤维层接触热阻的计算公式,并分析了纤维层填充压力和松紧度对接触热阻和热传导性能的影响,从而为改进金属多层隔热结构的性能和可靠性提供了参考。

关键词：多层隔热结构二热流法辐射热阻接触热阻热传导