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Gigantic Genomes Provide Empirical Tests of Transposable Element Dynamics Models

Genomics, Proteomics & Bioinformatics 2021年第1期19卷 123-139页

作者： Jie Wang Michael W.Itgen Huiju Wang Yuzhou gong Jianping Jiang Jiatang Li cheng Sun Stanley K.Sessions Rachel Lockridge Mueller CAS key laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation key laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Department of Biology Colorado State UniversityFort CollinsCO 80523USA School of Information and Safety Engineering Zhongnan University of Economics and LawWuhan 430073China institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China Biology Department Hartwick CollegeOneontaNY 13820USA

Transposable elements(TEs)are a major determinant of eukaryotic genome *** collective properties of a genomic TE community reveal the history of TE/host evolutionary dynamics and impact present-day host structure and function,from genome to organism *** rare cases,TE community/genome size has greatly expanded in animals,associated with increased cell size and changes to anatomy and ***,we characterize the TE landscape of the genome and transcriptome in an amphibian with a giant genome—the caecilian Ichthyophis bannanicus,which we show has a genome size of 12.2 *** are an important model system because the clade includes independent cases of genomic *** *** genome differs compositionally from other giant amphibian genomes,but shares a low rate of ectopic recombination-mediated *** examine TE activity using expression and divergence plots;TEs account for 15%of somatic transcription,and most superfamilies appear *** quantify TE diversity in the caecilian,as well as other vertebrates with a range of genome sizes,using diversity indices commonly applied in community *** synthesize previous models that integrate TE abundance,diversity,and activity,and test whether the caecilian meets model predictions for genomes with high TE *** propose thorough,consistent characterization of TEs to strengthen future comparative *** analyses will ultimately be required to reveal whether the divergent TE assemblages found across convergent gigantic genomes reflect fundamental shared features of TE/host genome evolutionary dynamics.

关键词： TE expression TE diversity index Genome size evolution Caecilian Transposon ecology

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Theoretical Study of the Molecular and Electronic structures of CPDT-TCNQ and Its Difluoro and Dimethyl Derivatives

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Chinese Journal of Structural Chemistry 2006年第8期25卷 927-936页

作者： gong Zhi-Jun LI Qian-Shu College of Chemistry and Environmental Engineering Yangtze University Jingzhou Hubei 434023 China Department of Chemistry Beijing Institute of Technology Beijing 100081 China

CPDT-TCNQ and its derivatives are good candidates for charge-transfer acceptors. In this work, the electronic ground and excited states of CPDT-TCNQ as well as its difluoro and dimethyl derivatives are studied. The ground state optimized structures and energies were obtained using a restricted （closed-shell） density functional theory （DFT） as approximated by the various hybrid functionals （RB3LYP, RB3P86, RB3PW91）. The 6-31G＊＊ and 6-31＋G＊＊ basis sets were employed in calculations. All derivatives are planar and exhibit a quinoid structure in their electronic ground states. The energy and oscillator strength of the first 15 singlet-singlet electronic transitions have been investigated by applying the dine-dependent density functional theory （TD-DFT） approximations to the correspondingly optimized ground state geometries. The results show the strongest absorption in electronic spectra of molecules due to the HOMO-LUMO electronic transition of the thiophene backbone.

关键词： ground state quinoid structure excited state TD-DFT 6-31G** 6-31+G**

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Surface profile and microstructure of laser peened Ti-6Al-4V

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Rare Metals 2012年第5期31卷 430-433页

作者： ZOU Shikun gong Shuili GUO Enming College of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China beijing aeronautical Manufacturing technology Research institute Beijing 100024 China

The surface profile of laser peening with square spots was compared with that of circle spots, and the microstructure of laser peened titanium alloy Ti-6Al-4V in the center of a square spot and at the edge of the square spot was investigated in this paper. The results show that a smaller size crystal is produced at the edge of square spots because the shearing strain produces nanoscale crystals in laser peening titanium alloy Ti-6Al-4V.

关键词： laser peening surface profile square spot Ti-6Al-4V nanoscale crystals

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四川盆地长宁地区龙马溪组页岩气运移主控因素

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天然气地球科学 2024年第7期35卷 1223-1235页

作者：王国臻姜振学张原豪陈瑞华宫厚健贺世杰中国石油大学(北京)非常规油气科学技术研究院北京102249 中国石油新疆油田公司勘探开发研究院新疆克拉玛依834000 中国石油大学(北京)油气资源与探测国家重点实验室北京102249 中国石油大学(北京)地球科学学院北京102249

页岩气的运移是页岩气富集过程中十分重要的地质作用,计算流体力学方法可研究页岩气运移现象。基于计算流体动力学原理,建立了包含地层倾角与物性要素的抽象物理模型,采用控制变量法查明了其对气体运移的控制作用;以四川盆地长宁地区典... 详细信息

页岩气的运移是页岩气富集过程中十分重要的地质作用,计算流体力学方法可研究页岩气运移现象。基于计算流体动力学原理,建立了包含地层倾角与物性要素的抽象物理模型,采用控制变量法查明了其对气体运移的控制作用;以四川盆地长宁地区典型页岩气藏剖面为研究对象,推导了实际地质条件下的页岩气藏古压力、古含气量演化数学方程,并将方程计算结果作为初始条件,采用流体动力学方法模拟了页岩气藏宏观动态演化过程。研究结果表明:地层倾角控制了层理面受到的正应力与顺层方向的气体压力梯度,地层倾角越大,地层层面上所受的压实越弱,顺层面方向上压力梯度就越大,气体运移能力就越强;气体在运移过程中总是沿着物性优势通道运移,通道与围岩物性级差越大,控制油气运移的作用就越强;长宁背斜页岩气运移主要受控于地层抬升,导致垂向扩散量相对较少,低部位气藏对高部位有侧向运移补给;天宫堂末次构造早期正断层活动导致下倾方向渗流损失较大,尽管后期逆断层抑制了垂向扩散损失,但气藏含气量仍然较低。

关键词：长宁地区龙马溪组页岩气运移 CFD模拟

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碳纳米管杂化结构增强复合材料电学和力学性能研究进展

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功能材料 2024年第4期55卷 4037-4050页

作者：唐延洪龚俊刘愚李业军宋鹏李俊雄湖南科技大学机电工程学院湖南湘潭411201 湖南博邦山河新材料有限公司长沙410119 清华大学化学工程系北京100084 中南大学粉末冶金研究院长沙410083

碳纳米管作为一维纳米材料,具有优异的电学、热学、力学等性能,被广泛地用作复合材料的增强剂。根据碳纳米管杂化结构类型,综述了碳纳米管/颗粒材料、碳纳米管/纤维材料、碳纳米管/片层材料、碳纳米管/轻质泡沫材料等结构在电学性能和... 详细信息

碳纳米管作为一维纳米材料,具有优异的电学、热学、力学等性能,被广泛地用作复合材料的增强剂。根据碳纳米管杂化结构类型,综述了碳纳米管/颗粒材料、碳纳米管/纤维材料、碳纳米管/片层材料、碳纳米管/轻质泡沫材料等结构在电学性能和力学性能方面的研究进展,阐述了各种杂化结构的电学性能和力学性能增强机理,分析了各种杂化结构的优势,为碳纳米管杂化材料的构建和设计提供了依据。

关键词：碳纳米管杂化材料力学性能电学性能

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AlGaN基深紫外LED的可靠性研究及寿命预测

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光电子技术 2024年第2期44卷 106-115页

作者：宫明峰孙雪娇雷程梁庭李丰超谢宇李开心刘乃鑫中北大学省部共建动态测试技术国家重点实验室太原030051 中国科学院半导体研究所北京100083 山西中科潞安紫外光电科技有限公司山西长治046000

围绕AlGaN基深紫外LED的外延生长、工艺制备等因素对深紫外LED可靠性的影响以及加速寿命预测等方面开展了系统的研究。探索了量子垒(Quantum Barrier,简称QB)中Al组分、电子阻挡层(Electron Barrier Layer,简称EBL)中Al组分、同尺寸芯... 详细信息

围绕AlGaN基深紫外LED的外延生长、工艺制备等因素对深紫外LED可靠性的影响以及加速寿命预测等方面开展了系统的研究。探索了量子垒(Quantum Barrier,简称QB)中Al组分、电子阻挡层(Electron Barrier Layer,简称EBL)中Al组分、同尺寸芯片不同台面面积等因素对深紫外LED可靠性的影响,确定QB结构Al组分为74%,EBL结构Al组分为75%,台面面积为P68。对优化后的深紫外LED设计了热、电应力老化试验,结合阿伦纽斯模型、逆幂律模型、指数最小二乘拟合对深紫外LED的寿命进行预测。实验结果表明,随着电、热应力的增加,深紫外LED可靠性随之降低,阿伦纽斯模型预测寿命为5027 h,逆幂律模型预测寿命为5400 h,正常工作电流40 mA下,深紫外LED实际寿命为5582 h,逆幂律模型预测精度较阿伦纽斯模型提升了6.7%。本研究将为提高深紫外LED的可靠性和产品应用普及提供坚实的理论基础。

关键词： AlGaN 深紫外发光二极管可靠性寿命预测

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A pure blue light emitting binaphthyl derivative:Synthesis and properties

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Chinese Chemical Letters 2008年第4期19卷 431-434页

作者： Qing Guo He Zeng Ze Chu Gang Tie Lei An Jun Qin Hong Zhen Lin Feng Lian Bai Jian gong cheng Yong Qiu Shanghai institute of Microsystem and Information technology Chinese Academy of SciencesShanghai 200050China key laboratory of Organic Solids Centre for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080China Department of Chemistry Tsinghua UniversityBeijing 100084China

A binaphthyl derivative with pyrene on 3 and 3＇ positions was synthesized and characterized via Suzuki coupling reaction. Emission maximum in solution was located at 390 nm with a quantum efficiency of 68% by taking 9,10-diphenyl anthracene as reference,while it is shifted to 450 nm with FWHM of 104 nm resulting from aggregation state in solid *** transition temperature（Tg）and decomposition temperature were measured to be 184 and 447℃,respectively,by DSC and *** its photoluminescence spectrum,electroluminescent spectrum peaked at about 460 nm and shows a FWHM of 69 nm corresponding to a pure blue *** turn-on voltage,luminance and efficiency maximum were 5 V,2953 cd/m^2 and 1.37cd/A with CIE color coordinate of（0.16,0.15）,in the device structure of ITO/NPB（40nm）/PY-BN-PY（15nm）/BPhen（40nm）/Mg：Ag.

关键词： Binaphthyl Pyrene Suzuki reaction Photoluminescence Electroluminescence

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Scheme of negative acoustic radiation force based on a multiple-layered spherical structure

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Chinese Physics B 2024年第1期33卷 477-487页

作者：宫门阳徐鑫乔玉配刘杰惠何爱军刘晓宙 key laboratory of Modern Acoustics Institute of Acoustics and School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China School of Electronic Science and Engineering Nanjing UniversityNanjing 210023China State key laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has become a research hotspot. In this paper, a scheme of realizing negative ARF based on the multiple-layered spherical structure design is proposed. The specific structure and design idea are presented. Detailed theoretical calculation analysis is carried *** simulations have been performed to verify the correctness of this prediction. The conjecture that the suppression of backscattering can achieve negative ARF is verified concretely, which greatly expands the application prospect and design ideas of the ARF. This work has laid a theoretical foundation for realizing precise control of the structure.

关键词： acoustic tweezers negative acoustic radiation force particle manipulation

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PBL抗剪传力钢筋连接接头受拉力学性能试验

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哈尔滨工程大学学报 2024年第7期45卷 1391-1399页

作者：龚超梁梓豪张素梅李孝忠梁伟桥闫贵海姚志东中冶建筑研究总院有限公司华南事业部北京100088 中国五矿集团有限公司科技管理部北京100010 哈尔滨工业大学(深圳)土木与环境工程学院深圳518055

装配式混凝土构件间钢筋的连接是其适用性和经济性的关键环节,针对国内工程常用的灌浆套筒和约束浆锚钢筋连接技术存在施工难度大、效率低、质量不易检验等问题,本文提出了PBL-穿孔钢筋连接接头、PBL-穿孔钢管连接接头和PBL-U形钢筋连... 详细信息

装配式混凝土构件间钢筋的连接是其适用性和经济性的关键环节,针对国内工程常用的灌浆套筒和约束浆锚钢筋连接技术存在施工难度大、效率低、质量不易检验等问题,本文提出了PBL-穿孔钢筋连接接头、PBL-穿孔钢管连接接头和PBL-U形钢筋连接接头3种钢筋连接接头,实现预制混凝土单元间钢筋应力的传递,具有施工简便、质量易保证、成本低等优势。对这3种钢筋接头进行了6组参数共18个钢筋接头试件的拉伸性能试验,研究了新型接头试件的破坏模式、承载力和变形能力等,得到各参数对新型接头拉伸强度的影响规律,并对不同接头的受拉力学性能进行对比分析。研究结果表明:3种钢筋连接接头能够实现钢筋应力的有效传递,验证了新型钢筋连接接头的可行性。

关键词：装配式混凝土钢筋连接接头 PBL剪力键钢管混凝土拉伸试验裂缝发展破坏模式受拉承载力

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Switching control of morphing aircraft based on Q-learning

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Chinese Journal of Aeronautics 2020年第2期33卷 672-687页

作者： Ligang gong Qing WANG Changhua HU Chen LIU School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Science and technology on Space Intelligent Control laboratory Beijing Institute of Control EngineeringBeijing 100190China Xi’an institute of High technology Xi’an 710025China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China beijing institute of Electric System Engineering Beijing 100854China

This paper investigates a switching control strategy for the altitude motion of a morphing aircraft with variable sweep wings based on *** morphing process is regarded as a function of the system states and a related altitude motion model is ***,the designed controller is divided into the outer part and inner part,where the outer part is devised by a combination of the back-stepping method and command filter technique so that the’explosion of complexity’problem is ***,the integrator structure of the altitude motion model is exploited to simplify the back-stepping design,and disturbance observers inspired from the idea of extended state observer are devised to obtain estimations of the system *** control input switches from the outer part to the inner part when the altitude tracking error converges to a small value and linear approximation of the altitude motion model is *** inner part is generated by the Q-learning algorithm which learns the optimal command in the presence of unknown system matrices and *** is proved rigorously that all signals of the closed-loop system stay bounded by the developed control method and controller switching occurs only ***,comparative simulations are conducted to validate improved control performance of the proposed scheme.

关键词： Back-stepping Command filter Disturbance observer Morphing aircraft Q-learning Switching control

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