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Epitaxial growth and thermostabiUty of cubic and hexagonal SrMnO3 films on SrTiO3（111）

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Frontiers of physics 2015年第3期10卷 83-88页

作者： Rui-Nan Song Min-Hui Hu Xiang-Rong Chen jian-dong guo Institute of Atomic and Molecular Physics College of Physical Science and Technology Sichuan University Chengdu 610065 China Institute of Physics Chinese Academy of Sciences Beijing 100190 China Key Laboratory of High Energy Density Physics and Technology of Ministry of Education Sichuan University Chengdu 610064 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

The growth of SrMnO3 films on SrTiO3（111） substrates by pulsed laser deposition was studied and found to produce cubic and hexagonal （4H） structures in the SrMnO3 films. By adjusting the substrate temperature and oxygen pressure, the stability of the two phases was fine-tuned, resulting in the growth of cubic-SrMnO3（lll） or 4H-SrMn03（0001） film, with the 4H phase being the more stable at room temperature and ambient pressure in the bulk form. The growth temperature of the cubic phase was also further lowered relative to the bulk thermodynamics by strain at the heterointerface, and once obtained, it was stable at temperatures of up to 800 ℃.

关键词： oxide film pulsed laser deposition heteroepitaxy SrMn03

Identification of the strain-specifically truncated nonstructural protein 10 of porcine reproductive and respiratory syndrome virus in infected cells

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Journal of Integrative Agriculture 2018年第5期17卷 1171-1180页

作者： ZHANG Zhi-bang XU Lei WEN Xue-xia dong jian-guo ZHOU Lei GE Xin-na YANG Han-chun guo Xin Key Laboratory of Animal Epidemiology and Zoonosis Ministry of Agriculture/College of Veterinary MedicineChina Agricultural University/State Key Laboratory of AgrobiotechnologyChina Agricultural University

The nonstructural protein 10（nsp10） of porcine reproductive and respiratory syndrome virus（PRRSV） encodes for helicase which plays a vital role in viral replication. In the present study, a truncated form of nsp10, termed nsp10 a, was found in PRRSV-infected cells and the production of nsp10 a was strain-specific. Mass spectrometric analysis and deletion mutagenesis indicated that nsp10 a may be short of about 70 amino acids in the N terminus of nsp10. Further studies by rescuing recombinant viruses showed that the Glu-69 in nsp10 was the key amino acid for nsp10 a production. Finally, we demonstrated that nsp10 a exerted little influence on the growth kinetics of PRRSV in vitro.

关键词： porcine reproductive and respiratory syndrome virus(PRRSV) nonstructural protein 10(nsp10) viral replication

Controlled growth of complex polar oxide films with atomically precise molecular beam epitaxy

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Frontiers of physics 2018年第5期13卷 9-21页

作者： Fang Yang Yan Liang Li-Xia Liu Qing Zhu Wei-Hua Wang Xue-Tao Zhu jian-dong guo Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

At heterointerfaces between complex oxides with polar discontinuity, the instability-induced electric field may drive electron redistribution, causing a dramatic change in the interracial charge density. This results in the emergence of a rich diversity of exotic physical phenomena in these quasi-two-dimensional systems, which can be further tuned by an external field. To develop novel multifunctional electronic devices, it is essential to control the growth of polar oxide films and heterointerfaces with atomic preci- sion. In this article, we review recent progress in control techniques for oxide film growth by molecular beam epitaxy （MBE）. We emphasize the importance of tuning the microscopic surface structures of polar films for developing precise growth control techniques. Taking the polar SrTiO3 （110） and （111） surfaces as examples, we show that, by keeping the surface reconstructed throughout MBE growth, high-quality layer-by-layer homoepitaxy can be realized. Because the stability of different reconstruc- tions is determined by the surface cation concentration, the growth rate from the Sr/Ti evaporation source can be monitored in real time. A precise, automated control method is established by which insulating homoepitaxial SrTiO3 （110） and （111） films can be obtained on doped metallic substrates. The films show atomically well-defined surfaces and high dielectric performance, which allows the surface carrier concentration to be tuned in the range of -1013/cm2. By applying the knowledge of microstructures from fundamental surface physics to film growth techniques, new opportunities are provided for material science and related research.

关键词： complex oxide films molecular beam epitaxy surface reconstruction heterointerfaces

Studies on the Growth Habits and Characteristics of Two Polyploid Indica-Japonica Hybrid Rice with Powerful Heterosis

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Agricultural Sciences in China 2007年第3期6卷 265-274页

作者： SONG Zhao-jian DU Chao-qun DAI Bing-cheng CHEN dong-ling CHEN jian-guo CAI De-tian College of Life Science Hubei University Wuhan 430062 P.R.China

Based on a series of polyploid indica-japonica hybrid plant lines obtained from a new breeding strategy of using double predominance of wide cross and polyploidization to breed super flee, two polyploid indica-japonica hybrids, PSR073 and PSR120 were studied in their growth periods to show the powerful heterosis in a larger scale and to study the characteristics of polyploid indica-japonica hybrids more elaborately. The leaf age, tiller growth, flowering habits, and agronomic traits of them were observed to analyze their growth habits and characteristics. The results showed that *** traits of PSR073 and PSR120, such as the plant height, panicle length, grain length, grain width, and 1000-grain weight, all acquired obvious predominance of polyploidy, and that the seed setting rate was more than 83%. No significant difference was observed between the two tetraploids and common diploids in the leaf age, tiller growth, and flowering habits. It was concluded that the characteristics of the two powerful heterosis polyploid hybrids were different from those of the polyploid rice reported earlier. Wide cross and polyploidization had no negative effects on their growth habits and characteristics; on the contrary these had powerful heterosis. This had provided theoretic and practical evidences for their application to agricultural production.

关键词： polyploid indica-japonica hybrids growth habits and characteristics heterosis seed setting rate

Signal Peptide of Potato PinII Enhances the Expression of Cry1Ac in Transgenic Tobacco

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 553-558页

作者： Yun-Jun LIU, Yuan YUAN, Jun ZHENG, Ya-Zhong TAO, Zhi-Gang dong,jian-Hua WANG, and guo-Ying WANGState Key Laboratory for Agrobiotechnology and National Center for Maize Improvement, China Agricultural University, Beijing 100094, China State Key Laboratory for Agrobiotechnology and National Center for Maize Improvement China Agricultural UniversityBeijing 100094 China

The modified Cry1Ac was expressed in transgenic tobacco plants. To allow secretion of the Cry1Ac protein into the intercellular space, the signal peptide sequence of potato proteinase inhibitor II (pinII) was N-terminally fused to the Cry1Ac encoding region. Expression of Cry1Ac in transgenic tobacco plants was assayed with ELISA. The results showed that pinII signal peptide sequence enhanced the expression of Cry1Ac protein and led to the secretion of the Cry1Ac protein in transgenic tobacco plants. GFP gene was also fused to the signal peptide sequence and transformed to tobacco. The results of fluorescent detection showed that GFP had localized in the apoplast of transgenic plants.

关键词： Cry1Ac signal peptide GFP transgenic tobacco

黏性土剪切带的形成与其屈服的内在联系的探索

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岩土力学 2007年第5期28卷 851-854页

作者：董建国李蓓同济大学地下建筑与工程系上海200092 水利部太湖流域管理局上海200434

为了深入了解黏性土的应力应变特性,对黏性土进行了量测侧向变形的不排水平面应变压缩试验。分析试验结果发现,黏性土局部化变形的起始点与黏性土样中的孔隙水压力的突然增长的转折点非常接近,而孔隙水压力开始急剧增长变化的转折点为... 详细信息

为了深入了解黏性土的应力应变特性,对黏性土进行了量测侧向变形的不排水平面应变压缩试验。分析试验结果发现,黏性土局部化变形的起始点与黏性土样中的孔隙水压力的突然增长的转折点非常接近,而孔隙水压力开始急剧增长变化的转折点为其屈服点,说明黏性土剪切带开始形成的偏应力为其屈服点,超过此点后黏性土局部化变形加剧,这个发现将有助于土体在强度理论、变形和稳定分析等方面的深入研究。

关键词：黏性土局部化变形偏应力孔隙水压力屈服点

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基坑设计考虑粘性土变形局部化的探讨

岩土工程学报 2006年第B11期28卷 1383-1386页

作者：董建国袁聚云同济大学地下建筑与工程系上海200092

根据上海软土在固结不排水平面应变压缩试验条件下应变局部化和剪切带形成的实测研究结果,发现粘性土剪切带开始形成的偏应力为其屈服点。过此点后粘性土局部化变形加剧。这将有助于土体在强度理论、变形和稳定分析等方面的深入研究。为... 详细信息

根据上海软土在固结不排水平面应变压缩试验条件下应变局部化和剪切带形成的实测研究结果,发现粘性土剪切带开始形成的偏应力为其屈服点。过此点后粘性土局部化变形加剧。这将有助于土体在强度理论、变形和稳定分析等方面的深入研究。为此,在深入研究变形局部化的同时,着重研究考虑粘性土变形局部化的深基坑计算参数问题。

关键词：粘性土局部化变形剪切带开始形成的偏应力屈服点深基坑计算参数

A gain-flatness optimization solution for feedback technology of wideband low noise amplifiers

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第7期12卷 608-613页

作者： Zhen-hua LI,Bang-hong guo,Zheng-jun WEI ,Song-hao LIU,Nan CHENG,Jin-dong WANG,jian-jun guo,Long YAN (Key Laboratory of Photonic Information Technology of Guangdong Higher Education Institutes,SIPSE & LQIT,South China Normal University,Guangzhou 510006,China) Key Laboratory of Photonic Information Technology of Guangdong Higher Education Institutes SIPSE & LQIT South China Normal University Guangzhou China

The S parameter expression of high-frequency models of the high electron mobility transistors (HEMTs) with basic feedback structure,especially the transmission gain S 21,is presented and *** addition,an improved feedback structure and its theory are proposed and demonstrated,in order to obtain a better gain-flatness through the mutual interaction between the series inductor and the parallel capacitor in the feedback *** optimization solution for the feedback amplifier can eliminate the negative impacts on transmission gain S 21 caused by things such as resonance ***,our theory covers the shortage of conventional feedback amplifiers,to some extent.A wideband low-noise amplifier (LNA) with the improved feedback tech-nology is designed based on *** transmission gain is about 20 dB with the gain variation of 1.2 dB from 100 MHz to 6 *** noise figure is lower than 2.8 dB in the whole band and the amplifier is unconditionally stable.

关键词： Low-noise amplifier (LNA) Ultra-wideband HEMT Feedback Gain flatness

Probing Lattice Vibrations at SiO_2/Si Surface and Interface with Nanometer Resolution

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Chinese Physics Letters 2019年第2期36卷 40-48页

作者： Yue-Hui Li Mei Wu Rui-Shi Qi Ning Li Yuan-Wei Sun Cheng-Long Shi Xue-Tao Zhu jian-dong guo Da-Peng Yu Peng Gao International Center for Quantum Materials Peking University Electron Microscopy Laboratory School of Physics Peking University Nion Company Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Shenzhen Key Laboratory of Quantum Science and Engineering Collaborative Innovation Centre of Quantum Matter

Recent advances in monochromatic aberration corrected electron microscopy make it possible to detect the lattice vibrations with both high-energy resolution and high spatial resolution. Here, we use sub-10 meV electron energy loss spectroscopy to investigate the local vibrational properties of the SiO_2/Si surface and interface. The energy of the surface mode is thickness dependent, showing a blue shift as z-thickness(parallel to the fast electron beam)of SiO_2 film increases, while the energy of the bulk mode and the interface mode keeps constant. The intensity of the surface mode is well-described by a Bessel function of the second kind. The mechanism of the observed spatially dependent vibrational behavior is discussed and compared with dielectric response theory analysis. Our nanometer scale measurements provide useful information on the bonding conditions at the surface and interface.

关键词： SiO