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Rapid growth of angle-confined large-domain graphene bicrystals

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Nano Research 2017年第4期10卷 1189-1199页

作者： Huaying Ren Huan Wang Li Lin Miao Tang shuli zhao Bing Deng Manish Kumar Priydarshi Jincan Zhang Hailin Peng Zhongfan Liu Center for Nanochemistry Beijing Science and Engineering Center for Nanocarbons Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China

In the chemical vapor deposition growth of large-area graphene polycrystalline thin films, the coalescence of randomly oriented graphene domains results in a high density of uncertain grain boundaries （GBs）. The structures and properties of various GBs are highly dependent on the misorientation angles between the graphene domains, which can significantly affect the performance of the graphene films and impede their industrial applications. Graphene bicrystals with a specific type of GB can be synthesized via the controllable growth of graphene domains with a predefined lattice orientation. Although the bicrystal has been widely investigated for traditional bulk materials, no successful synthesis strategy has been presented for growing two-dimensional graphene bicrystals. In this stud34 we demonstrate a simple approach for growing well-aligned large-domain graphene bicrystals with a confined tilt angle of 30° on a facilely recrystallized single-crystal Cu （100） substrate. Control of the density of the GBs with a miso- rientation angle of 30° was realized via the controllable rapid growth of sub- centimeter graphene domains with the assistance of a cooperative catalytic surface-passivation treatment. The large-area production of graphene bicrystals consisting of the sole specific GBs with a tunable density provides a new material platform for fundamental studies and practical applications.

关键词： graphene bicrystal chemical vapor deposition surface engineering grain boundary heating device

Controlled synthesis of single-crystal SnSe nanoplates

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Nano Research 2015年第1期8卷 288-295页

作者： shuli zhao Huan Wang Yu Zhou Lei Liao Ying Jiang Xiao Yang Guanchu Chen Min Lin Yong wang Hailin Peng Zhongfan Liu Center for Nanochemistry Beijing National Laboratory for Molecular Sciences (BNLMS) College of Chemistry and Molecular Engineering Peking University Beijing 10087 I China Academy for Advanced Interdisciplinary Studies Peking University Beijing 10087 I China Center of Electron Microscopy and State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

Two-dimensional layered IV-VI chalcogenides are attracting great interest for applications in next-generation optoelectronic, photovoltaic, and thermoelectric devices. However, great challenges in the controllable synthesis of high-quality IV-VI chalcogenide nanostructures have hindered their in-depth studies and practical applications to date. Here we report, for the first time, a feasible synthesis of single-crystal IV-VI SnSe nanoplates in a controlled manner on mica substrates by vapor transport deposition. The as-grown SnSe nanoplates have approximately square shapes with controllable side lengths varying from I to 6 Dm. Electrical transport and optoelectronic measurements show that as-obtained SnSe nanoplates display p-type conductivity and high photoresponsivity.

关键词： SnSe IV-VI chalcogenide nanoplate two-dimensional layeredcrystals optoelectronics

Research on the Result of Calibration for the Location of the Seismic Array in Shanghai

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Earthquake Research in China 2007年第1期21卷 55-61页

作者： Yu Haiying Zhu Yuanqing zhao shuli Earthquake Administration of Shanghai Municipality Shanghai 200062 China

The paper proposes the calibration theory and methods for the Shanghai seismic array and analyzes the calibration results. As a result, the calibration results for the seismic array based on 2 typical earthquakes have been drawn; the difference of calibration results between Hokkaido and Honshu region in Japan is investigated. And calibration results of different directions, different epicenter distances and different magnitudes are probed into. The result shows that the location of earthquakes on the Shanghai seismic array is greatly improved.

关键词： Shanghai Array calibration Seismic array Apparent slowness

Ovarian tumor-associated microRNA-20a decreases natural killer cell cytotoxicity by downregulating MICA/B expression

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Cellular & Molecular Immunology 2014年第5期11卷 495-502页

作者： Jingyan Xie Mengna Liu Yujuan Li Yunzhong Nie Qiongyu Mi shuli zhao Nanjing First Hospital Nanjing Medical University Nanjing China State Key Laboratory of Reproductive Medicine Nanjing Medical University NanjingChina lmmunology and Reproductive Biology Lab of Medical School Nanjing University Nanjing 210093 jingyan Xie and Mengna Liu contributed equally to this work

MicroRNAs （miRNAs） are a class of small non-coding regulatory RNAs, and changes in miRNAs are involved in tumor origin and progression. Studies have shown that miR-20a is overexpressed in human ovarian cancer tissues and that this miRNA enhances long-term cellular proliferation and invasion capabilities. In this study, a positive correlation between serum miR-20a expression and ovarian cancer stage was observed. We found that miR-20a binds directly to the 3＇-untranslated region of MICA/B mRNA, resulting in its degradation and reducing its protein levels on the plasma membrane. Reduction of membrane-bound MICA/B proteins, which are ligands of the natural killer group 2 member D （NKG2D） receptor found on natural killer （NK） cells, y＋ T cells and CD8＋ T cells, allows tumor cells to evade immune-mediated killing. Notably, antagonizing miR-20a action enhanced the NKG2D-mediated killing of tumor cells in both in vitro and in vivo models of tumors. Taken together, our data indicate that increased levels of miR-20a in tumor cells may indirectly suppress NK cell cytotoxicity by downregulating MICA/B expression. These data provide a potential link between metastasis capability and immune escape of tumor cells from NK cells.

关键词： immune escape MICA/B miR-2Oa NKG2D ovarian cancer

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疲劳多裂纹扩展的常规态型近场动力学分析

哈尔滨工业大学学报 2019年第4期51卷 19-25页

作者：赵树力余音徐武上海交通大学航空航天学院上海200240

为改进疲劳多裂纹扩展问题的分析,建立了常规态型近场动力学的疲劳多裂纹扩展模拟方法.在常规态型近场动力学的理论框架基础上,采用近场动力学疲劳裂纹萌生和扩展模型,建立了一个可模拟疲劳裂纹萌生与扩展的平面应力近场动力学模型.针... 详细信息

为改进疲劳多裂纹扩展问题的分析,建立了常规态型近场动力学的疲劳多裂纹扩展模拟方法.在常规态型近场动力学的理论框架基础上,采用近场动力学疲劳裂纹萌生和扩展模型,建立了一个可模拟疲劳裂纹萌生与扩展的平面应力近场动力学模型.针对近场动力学疲劳模型计算量庞大的问题,又引入"临界断裂数"来优化模型的计算流程,提升模型的计算速度,以单边裂纹板为研究对象,通过选取不同"临界断裂数"的值寻求计算效率与裂纹路径精准度之间的平衡.从计算结果的对比中可以发现,当采用恰当的"临界断裂数"时,计算速度得到了较大的提升,同时裂纹仍能保证精准的形状.然后,该模型被用于非共线多裂纹板的疲劳破坏模拟仿真之中,当采用不同的"临界断裂数"时,计算运行得到的疲劳裂纹扩展路径以及相应的a-N曲线均能与实验得到的结果取得良好的吻合.研究结果表明,近场动力学疲劳分析方法不需引入断裂准则和预知裂纹路径,裂纹可以任意扩展.

关键词：近场动力学疲劳多处损伤 a-N曲线裂纹扩展

Estrogen upregulates MICA/B expression in human non-small cell lung cancer through the regulation of ADAM17

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Cellular & Molecular Immunology 2015年第6期12卷 768-776页

作者： Jing Ren Yunzhong Nie Mingming Lv Sunan Shen Ruijing Tang Yujun Xu Yayi Hou shuli zhao Tingting Wang The State Key Laboratory of Pharmaceutical Biotechnology Division of Immunology Medical School Nanjing University Nanjing China jiangsu Key Laboratory of Molecular Medicine Nanjing China State Key Laboratory of Reproductive Medicine Central Laboratory of Nanjing First Hospital Nanjing Medical University Nanjing China These authors contributed equally to this work

Estrogen is involved in promoting lung cancer cell division and metastasis. MICA and MICB function as ligands for NKG2D, an important immunoreceptor expressed on natural killer （NK） cells. However, whether estrogen regulates MICA/ B expression and affects tumor immune escape remains unknown. In this study, we measured the mRNA levels of MICA, MICB and ADAM 17in non-small cell lung cancer （NSCLC） cell lines treated with estrogen. Surface expression of MICA/B on LTEP-a2 and A549 was detected using flow cytometry. We demonstrate that both mRNA and secretory protein levels of M ICA/B in lung adenocarcinoma cell lines were upregulated by estradiol. Estradiol enhanced the expression of ADAM 17, which was associated with the secretion of MICA/B. This secretion of MICA/B downregulated the NKG2D receptor on the surface of NK92 cells and impaired the cytotoxic activity of NK cells. Estradiol enhanced the expression of ADAM17, which was associated with the secretion of MICA/B. Furthermore, a significant correlation between the concentration of estradiol and the expression of MICA was found in tumor tissues of NSCLC patients. Therefore, we conclude that estrogen can regulate the expression and secretion of MICA/B through ADAM 17, which helps lung cancer cells escape NKG2D-mediated immune surveillance.

关键词： ADAM17 estradiol MICA MICB tumor immune escape

Effects of Different Nitrogen Applications on Soil Physical, Chemical Properties and Yield in Maize (<i>Zea mays</i>L.)

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Agricultural Sciences 2014年第14期5卷 1440-1447页

作者： Heng Zhong Qiao Wang Xinhua zhao Qi Du Yue zhao Xiaoguang Wang Chunji Jiang shuli zhao Minjian Cao Haiqiu Yu Dawei Wang College of Agronomy Shenyang Agricultural University Shenyang China Corn Research Institute Liaoning Academy of Agriculture Science Shenyang China

Application of nitrogen (N) fertilizer is one of the most important approaches on improving maize grain yield. However, as is known to all, overuse N fertilizer not only leads to decline of N use efficiency and maize yield, but also leads to potential risk to environment pollution. This experiment was conducted to determine the effects of N fertilizer applications with nine different treatments on soil physical-chemical characters and maize grain yield using hybrid variety Zhengdan 958 in 2011 and 2012. Results indicated that the soil bulk densities of T2 (CK) and T1 were the lowest compared to other treatments in 2011 and 2012, respectively, whereas the soil bulk density of T5 in 2011 and T3 in 2012 were higher than other treatments. The soil porosity and field capacity of T5 in 2011 and T3 in 2012 were lower than other treatments, but those of CK in 2011 and T1 in 2012 were higher than other treatments. The pH values of T3 to T7 were lower than other treatments. These results indicated that the soil bulk densities were increased, whereas the soil porosity, field capacity and values pH were decreased by N application at different stages. N application could increase the N contents of leaf and stem, whereas less or excess N application should not significant improve maize yield. Although the soil organic matter and total N contents of T3 were the highest in both 2011 and 2012, the yield of T4 is the highest in both 2011 and 2012. The application amount, period and times of N fertilizer were important to maize yield.

关键词： Maize N Fertilizer Application Yield Soil Physical and Chemical Properties N Content

中国典型城市主要大气污染物的浓度水平及分布的比较研究

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生态环境学报 2014年第5期23卷 791-796页

作者：朱红霞赵淑莉中国环境监测总站北京100012

应用柱状图和箱线图对污染物分布情况进行对比分析,明确了2013上半年北京、沈阳、广州、上海和海口5个城市4项污染物（SO2、NO2、PM10、PM2.5）的日均浓度的分布范围。该组数据涉及的站点总计有49个,其中包含的数据量北京有1863个、沈阳... 详细信息

应用柱状图和箱线图对污染物分布情况进行对比分析,明确了2013上半年北京、沈阳、广州、上海和海口5个城市4项污染物（SO2、NO2、PM10、PM2.5）的日均浓度的分布范围。该组数据涉及的站点总计有49个,其中包含的数据量北京有1863个、沈阳有1670个、上海有1452个、广州有1574个、海口有780个。柱状图显示了这段时间每个城市各个站点4种污染物不同浓度的分布范围,北京的ρ（SO2）和ρ（NO2）分布较为集中,主要的质量浓度区间分别是0~40和40~80μg·m-3,分别占北京SO2和NO2总数据量的51.0%和49.7%,ρ（PM10）和ρ（PM2.5）则分布较为分散;沈阳分布较为集中的是ρ（NO2）和ρ（PM2.5）,主要的质量浓度区间分别是0~30和30~60μg·m-3,分别占沈阳NO2和PM2.5总数据量的52.2%和42.8%,ρ（SO2）和ρ（PM10）则分布较为分散;上海和广州分布较为集中的是低浓度下的ρ（SO2）,其他三项污染物分布较为分散。箱线图是利用每个城市所有站点得到的最大值、最小值、上四分位数、下四分位数和中位数的平均值绘制得到的,通过不同城市间的比较可见,同期ρ（SO2）的比较结果是ρ（沈阳）〉ρ（北京）〉ρ（广州）〉ρ（上海）〉ρ（海口）;ρ（NO2）较大的3个城市是北京、上海和广州;对于ρ（PM10）则只有广州和海口2个城市浓度较低,而对于ρ（PM2.5）高值集中在北京、广州和沈阳3个城市。通过谱图间的比较,并结合各个城市的气象条件及经济发展状况,从中可推测除背景点海口外,北京和沈阳主要的污染物是PM2.5和PM10,广州和上海主要的污染物是NO2和PM2.5;北京主要的污染来源是燃煤烟尘和机动车尾气,广州和上海主要的污染来源是机动车尾气,沈阳主要的污染来源是燃煤烟尘。研究结果可为典型城市的环境监管与大气污染控制提供科学依据。

关键词： 4项污染物柱状图箱线图分布来源

The impact of drought stress throughout the entire growth period on the grain yield and quality of common peanut and high-oleic-acid peanut

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The impact of drought stress throughout the entire growth pe...