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

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

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Establishment of Small Centralized Collection Processing Service System of Scattered Farming Waste

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Meteorological and Environmental Research 2015年第4期6卷 14-17页

作者： Bai Yanfei Wang Zichen Wu Hao Wang Haiqin shen jianning Wu Tianxiang Guan Yongxiang Liang Yonghong Jiangsu Station of Agro-Ecological Monitoring and Protection Circular Agricultural Research Center Jiangsu Academy of Agricultural Sciences

In order to advance pollution control and promote agricultural source pollution reduction of Jiangsu Province, based on the practical expe- rience of Lijia Livestock and Poultry Manure Processing Center in Wujin District, Changzhou City, Jiangsu Province, new ways of controlling small scattered livestock and poultry breeding pollution, with characteristics of ＂ unified collection, centralized processing, social services, and compre- hensive utilization＂, were discussed through establishing the collection processing service system, innovating operation system and mechanism, and transforming the mode of government supervision and management.

关键词： Small scale Livestock and poultry breeding Collection System Comprehensive utilization China

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淤泥土中钢筋混凝土顶管管道的计算分析与比较

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特种结构 2015年第3期32卷 107-112页

作者：陈军沈建宁南京市市政设计研究院有限责任公司

采用顶管法施工的地下钢筋混凝土管道在设计计算中存在一些问题,因此本文探讨了管道结构的承载能力和抗裂计算方法,研究了不同设计规程对淤泥土中顶管管道的土压力计算理论,并通过某淤泥土中顶管工程实例的计算,首先对采用两种设计规程... 详细信息

采用顶管法施工的地下钢筋混凝土管道在设计计算中存在一些问题,因此本文探讨了管道结构的承载能力和抗裂计算方法,研究了不同设计规程对淤泥土中顶管管道的土压力计算理论,并通过某淤泥土中顶管工程实例的计算,首先对采用两种设计规程的计算结果进行了分析和比较,再与我国给水排水国家标准图集和江苏省地方标准图集有关顶管的覆土荷载条件进行了对比。计算结果表明以两种规程计算的管道荷载和内力差异较大,淤泥土中钢筋混凝土顶管管道采用我国现行顶管规程计算时,管道的允许覆土厚度小于标准图集允许的最大覆土厚度。

关键词：钢筋混凝土管道顶管淤泥土层计算分析

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Parameterization of Sheared Entrainment in a Well-developed ***Ⅱ:A Simple Model for Predicting the Growth Rate of the CBL

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Advances in Atmospheric Sciences 2016年第10期33卷 1185-1198页

作者： Peng LIU jianning SUN Lidu shen School of Atmospheric Sciences&Institute for Climate and Global ChangeNanjing UniversityNanjing 210023China Jiangsu Provincial Collaborative Innovation Center of Climate Change Nanjing 210023China

Following the parameterization of sheared entrainment obtained in the companion paper, Liu et al. （2016）, the present study aims to further investigate the characteristics of entrainment, and develop a simple model for predicting the growth rate of a well-developed and sheared CBL. The relative stratification, defined as the ratio of the stratification in the free atmosphere to that in the entrainment zone, is found to be a function of entrainment flux ratio （Ae）. This leads to a simple expression of the entrainment rate, in which Ae needs to be parameterized. According to the results in Liu et al. （2016）, Ae can be simply expressed as the ratio of the convective velocity scale in the sheared CBL to that in the shear-free CBL. The parameterization of the convective velocity scale in the sheared CBL is obtained by analytically solving the bulk model with several assumptions and approximations. Results indicate that the entrainment process is influenced by the dynamic effect, the interaction between mean shear and environmental stratification, and one other term that includes the Coriolis effect. These three parameterizations constitute a simple model for predicting the growth rate of a well-developed and sheared CBL. This model is validated by outputs of LESs, and the results show that it performs satisfactorily. Compared with bulk models, this model does not need to solve a set of equations for the CBL. It is more convenient to apply in numerical models.

关键词： sheared convective boundary layer relative stratification parameter entrainment rate entrainment flux ratio,convective velocity scale

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Characteristics of Secondary Circulations in the Convective Boundary Layer over Two-Dimensional Heterogeneous Surfaces

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Journal of Meteorological Research 2016年第6期30卷 944-960页

作者： shen Lidu SUN jianning and LIU Peng School of Atmospheric Sciences & Institute for Climate and Global Change Nanjing University Jiangsu Provincial Collaborative Innovation Centre of Climate Change School of Earth and Space Sciences University of Science and Technology of China

Large-eddy simulations are conducted to investigate the impacts of the scale of chessboard-like heteroge- neous surface heating and the background wind on secondary circulations （SCs） in the convective boundary layer （CBL）. When the wind blows along the diagonal of the chessboard pattern, the cases with different heterogeneity length scales （λ = 1.2, 2.4, and 4.8 km） and weak background wind （U = 2.5 m s-1） suggest that there exists a threshold for the roll-like SCs, which is satisfied when the heterogeneity length scale is 1.6 times the boundary layer height （λ = 1.6zi）. During the CBL development, the SC intensity increases before this threshold is met, whereas it decreases thereafter. The cases with different background wind speeds （U = 2.5, 5.0, and 10.0 m s-1） and relatively large heterogeneity length scale （λ = 4.8 km） show that the SCs are strengthened by larger wind speeds when the heterogeneity length scale is so large that the threshold cannot be met during the CBL development. Another case with wind direction along neither the diagonal nor the side of the chessboard pattern shows that the roll-like SCs can still be triggered, but the roll axes are orientated along the diagonal of the chessboard pattern rather than along the wind direction.

关键词： background wind convective boundary layer heterogeneous surface large-eddy simulation secondary circulation turbulence

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Photovoltaic molecules based on vinylene-bridged oligothiophene applied for bulk-heterojunction organic solar cells

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Journal of Energy Chemistry 2018年第2期27卷 426-431页

作者： Jing Zhang Pan Yin Linjun Xu Ping shen Mingfu Ye Ningyi Yuan jianning Ding School of Material Science & Engineering Jiangsu Collaborative Innovation Center of Photovoltaic Science & Engineering Changzhou University Changzhou 213164 Jiangsu China College of Chemistry and Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education Xiongtan University Xiangtan 411105 Hunan China School of Chemistry and Chemical Engineering Anhui University of Technology Maanshan 243002 Anhui China

We have synthesized two photovoltaic molecules（HEX-3TVT-ID and EH-3TVT-ID） based on vinylenebridged oligothiophene applied as donor for the solution-processable bulk-heterojunction organic solar cells（OSCs）. Vinylene unit was introduced as π-bridge in the oligothiophenes with 1,3-indenedione as end group and 4,4’-dihexyl-2,2’：5’,2’-terthiophene or 3’,4’-di（octan-3-yl）-2,2’：5’,2’-terthiophene as core,respectively. Due to the different substituent positions of the alkyl group relative to the vinylene unit in the terthiophene, HEX-3TVT-ID and EH-3TVT-ID show different optical and electrochemical properties, corresponding to the photovoltaic performance of the OSCs devices. The power conversion efficiency（PCE） of the OSCs based on a blend of HEX-3TVT-ID and PC71BM（1：0.8, weight ratio, 0.5% CN） reached 2.3%. In comparison, the OSCs based on the blend of EH-3TVT-ID and PC71BM in the weight ratio of 1：1 without the additive show a higher PCE of 2.7%, with a typically high VOC of 0.93 V, under the illumination of AM 1.5, 100 mW cm-2.

关键词： Organic solar cells Photovoltaic organic molecules Vinylene-bridged oligothiophene

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基于ANSYS的双圆弧齿轮接触应力有限元分析

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农业机械学报 2006年第10期37卷 139-141页

作者：屈文涛沈允文徐建宁西安石油大学机械工程学院西北工业大学机电学院

利用ANSYS软件的参数化设计语言APDL建立双圆弧齿轮的三维有限元单齿对接触静态模型,并对模型划分网格,施加载荷,获得了双圆弧齿轮的静态接触应力云图;基于ANSYS/LSDYNA建立了柔性体多齿动态接触模型,并对齿轮进行了动态接触分析。计算... 详细信息

利用ANSYS软件的参数化设计语言APDL建立双圆弧齿轮的三维有限元单齿对接触静态模型,并对模型划分网格,施加载荷,获得了双圆弧齿轮的静态接触应力云图;基于ANSYS/LSDYNA建立了柔性体多齿动态接触模型,并对齿轮进行了动态接触分析。计算分析结果为双圆弧齿轮的设计和使用提供了理论依据。

关键词：双圆弧齿轮动态接触应力云图 ANSYS 参数化设计

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Effects of parental empathy and emotion regulation on social competence and emotional/behavioral problems of school‐age children

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Pediatric Investigation 2020年第2期4卷 91-98页

作者： Kun Meng Yizhe Yuan Yali Wang jianning Liang Lijun Wang Jianfei shen Yanyu Wang Department of Foreign Languages Weifang Medical UniversityWeifangChina Department of Psychology Weifang Medical UniversityWeifangChina

Importance Parents take the lead in parent–child interactions and their emotion regulation ability and empathy during parenting may be associated with children’s emotional/behavioral ***,the specific mechanisms underlying these associations remain *** The present study aimed to explore the effect of parental empathy and emotional regulation on social competence and emotional/behavioral problems in school‐age *** A questionnaire‐based survey was conducted with 274 parents of 8–11‐year‐old children using Achenbach’s Child Behavior Checklist,the Emotion Regulation Questionnaire,and the Questionnaire of Cognitive and Affective *** Children with emotional/behavioral problems(n=37)had relatively lower social competence than children in a matched control group(n=37).Compared with the parents of children in the control group,parents of children with emotional/behavioral problems had significantly lower cognitive empathy scores,mainly manifested by low perspective‐taking and online simulation *** analysis showed that parental cognitive empathy had an indirect effect on children’s emotional/behavioral problems through children’s social *** Parental empathy may have a subtle influence on the social competence of school‐aged children,which further affects the severity of children’s emotional/behavioral problems.

关键词： Schoolage children Social competence Emotional/Behavioral problem Empathy Emotion regulation

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Long-term observation of air pollution-weather/climate interactions at the SORPES station： a review and outlook

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Frontiers of Environmental Science & Engineering 2016年第5期10卷 9-23页

作者： Aijun Ding Wei Nie Xin Huang Xuguang Chi jianning Sun Veli-Matti Kerminen Zheng Xu Weidong Guo Tuukka Petaja Xiuqun Yang Markku Kulmala Congbin Fu Joint International Research Laboratory of Atmospheric and Earth System Sciences (JirLATEST) Nanjing University Nanjing 210023 China Institute for Climate and Global Change Research School of Atmospheric Sciences Nanjing University Nanjing 210023 China Collaborative Innovation Center of Climate Change Jiangsu Province Nanjing 210023 China Department of Physics University of Helsinki Helsinki 00014 Finland

This work presents an overall introduction to the Station for Observing Regional Processes of the EarthSystem - SORPES in Nanjing, East China, and gives an overview about main scientific findings instudies of air pollution-weather/climate interactions obtained since 2011. The main results summarizedin this paper include overall characteristics of trace gases and aerosols, chemical transformationmechanisms for secondary pollutants like O3, HONO andsecondary ingrganic aerosols, and the airpollution- weather/climate interactions and feedbacks in mixed air pollution plumes from sources likefossil fuel combustion, biomass burning and dust storms. The future outlook of the development plan on instrumentation, networking and data-sharing for the SORPES station is also discussed.

关键词： Secondary pollution Ground-based measurement Planetary boundary layer meteorology Earth system processes

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异步电机变参数软起动仿真

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东南大学学报（自然科学版） 2012年第4期42卷 623-627页

作者：黄允凯沈培勇董剑宁林鹤云东南大学电气工程学院南京210096

为了解决异步电机软起动仿真中,因电机模型不准确带来的误差问题,通过对起动过程中电机等效电路参数变化规律的研究,提出一种变参数异步电机模型用于软起动仿真.该模型基于异步电机工作原理,直接通过电机铭牌额定数据估算起动和稳态时... 详细信息

为了解决异步电机软起动仿真中,因电机模型不准确带来的误差问题,通过对起动过程中电机等效电路参数变化规律的研究,提出一种变参数异步电机模型用于软起动仿真.该模型基于异步电机工作原理,直接通过电机铭牌额定数据估算起动和稳态时的等效电路参数,其中转子电阻和转子漏抗在起动过程中随转速的上升而变化,确保在关键运行点上的电机仿真计算性能与真实电机基本一致.在Matlab中建立了变参数异步电机和软起动仿真模型,对16 MW样机进行电流斜坡起动仿真,起动时间与现场实际起动时间的误差不超过3%.实验证明,该模型简单易行,且具有较高的精度,可以有效地模拟异步电机起动过程.

关键词：异步电机软起动变参数仿真分析

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