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A New Critical Nitrogen Dilution Curve for Rice Nitrogen Status Diagnosis in Northeast China

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Pedosphere 2018年第5期28卷 814-822页

作者： HUANG Shanyu MIAO Yuxin CAO Qiang yao yinkun ZHAO Guangming YU Weifeng SHEN Jianning YU Kang Georg BARETH International Center for Agro-Informatics and Sustainable Development College of Resources and Environmental Sciences China Agricultural University Beijing 100193 (China) Institute of Geography University of Cologne K5ln 50923 (Germany) Precision Agriculture Center Department of Soil Water and Climate University of Minnesota St. Paul 55108 (USA) National Engineering and Technology Center for Information Agriculture Nanjing Agricultural University Nanjing 210095 (China) Qixing Farm Jiansanjiang Jiamusi 156399 (China)

In-season diagnosis of crop nitrogen(N) status is crucial for precision N management. Critical N(N_c) dilution curve and N nutrition index(NNI) have been proposed as effective methods to diagnose N status of different crops. The N_c dilution curves have been developed for indica rice in the tropical and temperate zones and japonica rice in the subtropical-temperate zone, but they have not been evaluated for short-season japonica rice in Northeast China. The objectives of this study were to evaluate the previously developed N_c dilution curves for rice in Northeast China and to develop a more suitable N_c dilution curve in this region. A total of17 N rate experiments were conducted in Sanjiang Plain, Heilongjiang Province in Northeast China from 2008 to 2013. The results indicated that none of the two previously developed N_c dilution curves was suitable to diagnose N status of the short-season japonica rice in Northeast China. A new N_c dilution curve was developed and can be described by the equation N_c = 27.7 W^(-0.34) if W ≥ 1 Mg dry matter(DM) ha^(-1) or N_c = 27.7 g kg^(-1) DM if W < 1 Mg DM ha^(-1), where W is the aboveground biomass. This new curve was lower than the previous curves. It was validated using a separate dataset, and it could discriminate non-N-limiting and N-limiting nutritional conditions. Additional studies are needed to further evaluate it for diagnosing N status of different rice cultivars in Northeast China and develop efficient non-destructive methods to estimate NNI for practical applications.

关键词： japonica rice nitrogen nutrition index nitrogen use efficiency plant nitrogen concentration precision nitrogen mana-gement

GENOME EDITING:A GROUND BREAKING RESEARCH HAS BEEN RANKED TOP 10 ENGINEERING FRONTS FROM 2017 TO 2021

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Frontiers of Agricultural Science and Engineering 2022年第2期9卷 309-311页

作者： Jianxiang XU Yunzhou LI yinkun yao Jie ZHAO Jingyue TANG Zixuan FENG Sci-Tech Journal Centre Higher Education PressBeijing 100029China Editorial Office of Frontiers of Agricultural Science&Engineering China Agricultural UniversityBeijing 100193China

‘Global Engineering Fronts’ is a report released by the Chinese Academy of Engineering(CAE) every year since 2017, which aims to assemble talents in the field of engineering science and technology to represent the global engineering research and development fronts by reviewing global papers, patents, and other data. The results are also expected to provide a reference for people on responding to global challenges and achieving sustainable development.

关键词： EDIT ING sustainable

施磷对棉花磷素积累、分配、利用及产量的影响

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新疆农业科学 2020年第11期57卷 2004-2011页

作者：张炎姚银坤胡伟高媛汤明尧新疆农业科学院土壤肥料与农业节水研究所乌鲁木齐830091 农业部荒漠绿洲作物生理生态与耕作重点实验室乌鲁木齐830091

【目的】研究不同磷肥用量对海岛棉和陆地棉2个栽培种各主要生育阶段磷养分吸收、积累和分配规律,分析棉花对磷素营养的利用特性和磷肥效应。【方法】通过田间小区试验,在氮钾用量相同情况下,设置4个不同磷肥用量处理。【结果】2个棉花... 详细信息

【目的】研究不同磷肥用量对海岛棉和陆地棉2个栽培种各主要生育阶段磷养分吸收、积累和分配规律,分析棉花对磷素营养的利用特性和磷肥效应。【方法】通过田间小区试验,在氮钾用量相同情况下,设置4个不同磷肥用量处理。【结果】2个棉花栽培种全生育过程的磷积累趋势相似,磷积累量随增施磷肥用量而增加,吐絮成熟期,生殖器官的磷积累量远大于营养器官。从各生育期磷的积累量看,陆地棉对磷的吸收量要明显大于海岛棉。施磷对棉花增产,主要是增加了棉花单株铃数。海岛棉和陆地棉P2处理分别比P0处理增产11.16%和16%。由磷肥效应方程:海岛棉推荐施P2O5量为118.6 kg/hm^2,陆地棉推荐施P2O5量为80 kg/hm^2。海岛棉100 kg皮棉需要吸收P2O5平均为3.7 kg,陆地棉100 kg皮棉需要吸收P2O5平均为4.21 kg。【结论】施磷可以增加棉花对磷的吸收和积累,合理施用磷肥可以显著增加棉花产量。陆地棉磷的农学利用率、表观利用率和偏生产力都高于海岛棉,陆地棉较海岛棉对磷肥的吸收能力更强。

关键词：海岛棉磷陆地棉磷肥利用率产量

Comparison of alternative extraction methods for secretome profiling in human hepatocellular carcinoma cells

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Science China(Life Sciences) 2011年第1期54卷 34-38页

作者： CAO Jing SHEN ChengPin ZHANG Jun yao Jun SHEN HuaLi LIU yinkun LU HaoJie YANG PengYuan Institutes of Biomedical Sciences and Department of Chemistry Fudan University Shanghai 200032 China Liver Cancer Institute Zhongshan Hospital Fudan University Shanghai 200032 China

Secreted proteins are important sources for early detection and diagnosis of disease, and as such have received considerable attention. The extraction of low concentration proteins from large volumes of culture media, which are rich in salts and other compounds that interfere with most proteomics techniques, presents a problem for secretome studies. Ultrafiltration, precipitation, and dialysis are three major extraction methods that can be used to overcome this problem. The present study for the first time, compared the merits and shortcomings of these three methods, without bias. Centrifugal ultrafiltration provided the best extraction efficiency, and precipitation provided the highest number of identifiable proteins. The three methods yielded closely related, but different, information on the secretome; thus, they should be considered complementary or, at least, supplementary methods. Three hundred and sixty unique proteins were identified, including 211 potential secreted proteins. Compared with previous studies, this study also identified 42 new secreted proteins. The present study not only offers a reference for the selection of secretome extraction methods, but also expands the secretome database for the investigation of hepatocellular carcinoma.

关键词： hepatocellular carcinoma secretome protein extraction ultrafiltration precipitation dialysis LC-MS/MS

安装误差对双圆弧弧齿锥齿轮章动传动齿面接触特性的影响

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机械传动 2021年第12期45卷 85-92页

作者：陈琴黄银坤贾超姚立纲张俊福州大学机械工程及自动化学院福建福州350108

双圆弧弧齿锥齿轮章动传动的齿面接触特性对安装误差极为敏感。为揭示安装误差对齿面接触特性的影响规律,开展了含安装误差的双圆弧弧齿锥齿轮齿面接触分析。推导出章动式双圆弧弧齿锥齿轮齿面方程;借助齿面接触分析(TCA)获得齿轮副的... 详细信息

双圆弧弧齿锥齿轮章动传动的齿面接触特性对安装误差极为敏感。为揭示安装误差对齿面接触特性的影响规律,开展了含安装误差的双圆弧弧齿锥齿轮齿面接触分析。推导出章动式双圆弧弧齿锥齿轮齿面方程;借助齿面接触分析(TCA)获得齿轮副的齿面接触迹线和几何传动误差;通过算例分析了内、外锥齿轮锥点误差及齿轮副轴线交角误差对双圆弧弧齿锥齿轮副齿面接触特性的影响规律。研究表明,随着各项安装误差的增大,齿轮副接触迹线沿齿高方向的偏移量增大;凸、凹齿面接触迹线沿齿高方向的偏移量对安装误差变化的敏感程度不同;正的安装误差比负的安装误差对齿轮副传动误差影响更大。为获得理想的啮合性能,应合理控制章动式双圆弧弧齿锥齿轮副的安装误差。

关键词：双圆弧弧齿锥齿轮章动传动安装误差接触印痕传动误差

内啮合双圆弧摆线锥齿轮齿面建模与啮合特性仿真

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福州大学学报（自然科学版） 2022年第1期50卷 102-110页

作者：黄银坤吴祎煌陈琴贾超姚立纲张俊福州大学机械工程及自动化学院福建福州350108

针对斜航线式双圆弧内啮合锥齿轮副齿面难以高效加工的问题,提出一种端面滚切加工外锥齿轮,进而基于外锥齿轮的平面产形轮产成内锥齿轮的齿面设计方法.首先,以双圆弧齿形作为切削刀刃的基本齿廓,基于端面滚切方法建立双圆弧锥齿轮的平... 详细信息

针对斜航线式双圆弧内啮合锥齿轮副齿面难以高效加工的问题,提出一种端面滚切加工外锥齿轮,进而基于外锥齿轮的平面产形轮产成内锥齿轮的齿面设计方法.首先,以双圆弧齿形作为切削刀刃的基本齿廓,基于端面滚切方法建立双圆弧锥齿轮的平面产形轮.其次,根据平面产形轮与双圆弧内、外锥齿轮的展成运动关系,建立内、外锥齿轮的齿面方程.再次,通过精确求解齿面数据生成齿面“点云”,建立双圆弧锥齿轮副三维实体模型.最后,运用ANSYS仿真内啮合双圆弧锥齿轮副的啮合特性.实验结果表明:基于本方法生成的内啮合双圆弧锥齿轮工作齿面接触良好,可以实现正确啮合传动.当前研究可为内啮合双圆弧锥齿轮的高效加工提供理论依据.

关键词：双圆弧锥齿轮端面滚切法产形轮内啮合齿轮副啮合特性