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The Crop Journal 2017年第6期5卷 541-552页

作者： Xinglong Dai Yuechao Wang Xiuchun Dong Taifeng Qian Lijun Yin Shuxin Dong Jinpeng Chu Mingrong He State Key lab of Crop Biology/College of Agronomy Shandong Agricultural University Tai'an 271018 Shandong China Key lab of Crop Ecophysiology and Farming System Ministry of Agriculture Tai'an 271018 Shandong China College of Plant Science and Technology Huazhong Agricultural University Wuhan 430070 Hubei China Jining Agricultural Technology Extension Station Jining 272037 Shandong China

Lodging resistance of winter wheat(Trnticum aestivum L.) can be increased by late ***, whether grain yield and nitrogen use efficiency(NUE) can be maintained with delayed sowing remains unknown. During the 2013-2014 and 2014-2015 growing seasons, two winter wheat cultivars were sown on three dates(early sowing on October 1, normal so,wing on October8, and late sowing on October 15) to investigate the responses of lodging resistance, grain yield,and NUE to sowing date. No significant differences in lodging resistance, grain yield, or NUE between early and normal sowing were observed. Averaging over the two cultivars and years,postponing the sowing date significantly increased lodging resistance by 53.6% and 49.6%compared with that following early and normal sowing, respectively. Lodging resistance was improved mainly through a reduction in the culm height at the center of gravity and an increase in the tensile strength of the base internode. Late sowing resulted in similar grain yield as well as kernel weight and number of kernels per square meter, compared to early and normal *** over the two cultivars and years, delayed sowing resulted in a reduction in nitrogen uptake efficiency(UPE) by 11.0% and 9.9% compared to early and normal sowing, respectively,owing to reduced root length density and dry matter accumulation before anthesis. An average increase in nitrogen utilization efficiency(UTE) of 12.9% and 11.2% compared to early and normal sowing, respectively, was observed with late sowing owing to a reduction in the grain nitrogen concentration. The increase in UTE offset the reduction in UPE, resulting in equal NUEs among all sowing dates. Thus, sowing later than normal could increase lodging resistance while maintaining grain yield and NUE.

关键词： Grain yield Lodging resistance Nitrogen use efficiency Sowing date Winter wheat

Syntheses, Crystal Structures and Antifungal Activities of Two Compounds Containing Pyrazole and Pyrethroid Units

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1231-1237页

作者： ZHOU Bao-Han HUA Yun-Tao XU Bao-Ming MA Li HU Jia-Wen LIU Zhao-Jie School of Chemistry and Chemical Engineering Light Industry Division Hubei University of Technology Key lab of Pesticide and Chemical Biology Ministry of EducationCentral China Normal University

Compounds 1 （C15H17C1F3N303, Mr = 379） and 2 （C14H14C1F3N4os, Mr = 378） have been synthesized and their crystal structures were determined by single-crystal X-ray diffraction. Crystal 1 belongs to the triclinic system, space group P1 with a = 6.0223（19）, b = 9.324（3）, c = 15.936（5） A, a = 80.687（5）, β= 87.289（5）, ）, = 86.097（5）°, V= 880.4（5） A3, Z = 2, Dc = 1.433 g/cm3,μ（MoKa） = 0.266 mm^-1, F（000） = 392, R = 0.0861 and wR = 0.1999 for 2022 observed reflections with I 〉 2o（/）. Crystal 2 belongs to the triclinic system, space group PI with a = 7.7029（15）, b = 8.3371（16）, c = 14.410（3） A, a = 100.672（3）, β= 103.168（3）, ？ = 98.726（3）°, V = 876.1（3） A3, Z = 2, Dc= 1.451 g/cm^3,μ（MoKa） = 0.379 mm^-1, F（000） = 388, R = 0.0672 and wR = 0.2105 for 2725 observed reflections with I 〉 2σ（I）. Although the two compounds are similar with the same pyrazole and pyrethroid units, X-ray analysis reveals that their structures are completely different.

关键词： pyrazole, crystal structures, synthesis, antifungal activities

Hαcounterparts of X-ray bright points in the solar atmosphere

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Science China(Physics,Mechanics & Astronomy) 2012年第5期55卷 907-914页

作者： ZHANG Ping FANG Cheng ZHANG QingMin School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key lab of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of EducationNanjing 210093China

X-ray bright points （XBPs） are small-scale brightenings in the solar corona. Their counterparts in the lower atmosphere, how- ever, are poorly investigated. In this paper, we study the counterparts of XBPs in the upper chromosphere where the Hot line center is formed. The XBPs were observed by the X-ray Telescope （XRT） aboard the Hinode spacecraft during the observing plan （HOP0124） in August 2009, coordinated with the Solar Magnetic Activity Research Telescope （SMART） in the Kwasan and Hida Observatory, Kyoto University. It is found that there are 77 Hot brightenings in the same field of view of XRT, and among 57 XBPs, 29 have counterparts in the Hot channel. We found three types of relationship： Types a, b and c, correspond- ing to XBPs appearing first, Hot brightenings occurring first and no respective correspondence between them. Most of the strong XBPs belong to Type a. The Hot counterparts generally have double-kernel structures associated with magnetic bipoles and are cospatial with the footpoints of the XBP loops. The average lag time is -3 minutes. This implies that for Type a the heating, presumably through magnetic reconnection, occurs first in the solar upper atmosphere and then goes downwards along the small-scale magnetic loops that comprise the XBPs. In this case, the thermal conduction plays a dominant role over the non-thermal heating. Only a few events belong to Type b, which could happen when magnetic reconnection occurs in the chromosphere and produces an upward jet which heats the upper atmosphere and causes the XBP. About half of the XBPs belong to Type c. Generally they have weak emission in SXR. About 62% Hot brightenings have no corresponding XBPs. Most of them are weak and have single structures.

关键词： solar activity bright points small-scale brightenings

Performance and Stability of Polymer Solar Cells Based on the Blends of Poly(3-Hexylthiophene) and Indene-C_(60) Bis-Adduct

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Chinese Physics Letters 2016年第7期33卷 142-146页

作者：郭敏楠刘少伟郭娜杨利营秦文静印寿根 Key laboratory of Display Materials and Photoelectric Devices(Ministry of Education) School of Materials Science and EngineeringTianjin University of Technology Tianjin Key lab for Photoelectric Materials and Devices Tianjin University of Technology

The performance and morphology stability of polymer bulk heterojunetion solar cells based on poly（3-hexylthiophene）（P3HT） as the donor and indene-C6o bisadduct （ICBA） or methanofullerene [6,6]-phenyl C61-butyric acid methyl ester （PCBM） as the aeceptor are compared. Effect of the different donor and aeeeptor weight ratios on photo- voltaic performance of the P3HT：ICBA device is studied. The optimal device achieved power conversion emeiency of 5.51~o with dso of l0.86mA/cm2, Voc of 0.83 V, and fill factor （FF） of 61.1 % under AM 1.5G （lOOmW/cm2） simulated solar illumination. However, the stability measurement shows that cells based on P3HT：ICBA are less stable than those of the device based on P3HT：PCBM. Atomic force microscope results reveal that the morphol- ogy of the P3HT：ICBA film changed considerably during the storage periods due to unstable interpenetrating D-A network. This observation can be explained by the fact that there is lack of intermolecular hydrogen bonds in the P3HT：ICBA system. However, in the P3HT：PCBM system the molecules in the blend film are firmly held together in the solid state by means of intermoleeular hydrogen bonds originating from C-H. ~. os bonds （where os comes from the singly-bonded 0 atom of PCBM）, forming a stable three-dimensional network. The measured PL decay lifetimes for P3HT：PCBM and P3HT：ICBA systems are 33.66 ns and 35.34 ns, respectively, indicating that the P3HT：ICBA system has a less efficient exciton separation eftleiency than that of P3HT：PCBM, which may result in the interracial photogenerated charges accumulated on the D： A interface. Such progressive phase segregation between P3HT and ICBA eventually leads to the degradation in performance and deteriorates the stability of the device. We also present an approach to enhance the stability of P3HT：ICBA systems by adding PCBM as the second acceptor. Our results show that by carefully tuning the contents of PCBM as the second acceptor, more stable polymer solar cells

关键词： PCBM HT as for in of Hexylthiophene Performance and Stability of Polymer Solar Cells Based on the Blends of Poly Bis-Adduct on

Bearing Fault Diagnosis with DDCNN Based on Intelligent Feature Fusion Strategy in Strong Noise

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Computers, Materials & Continua 2023年第12期77卷 3423-3442页

作者： Chaoqian He Runfang Hao Kun Yang Zhongyun Yuan Shengbo Sang Xiaorui Wang College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan030024China Key lab of Advanced Transducers and Intelligent Control System of the Ministry of Education Taiyuan030024China

Intelligent fault diagnosis in modern mechanical equipment maintenance is increasingly adopting deep learning ***,conventional bearing fault diagnosis models often suffer from low accuracy and unstable performance in noisy environments due to their reliance on a single input ***,this paper proposes a dual-channel convolutional neural network(DDCNN)model that leverages dual data *** DDCNN model introduces two key ***,one of the channels substitutes its convolution with a larger kernel,simplifying the structure while addressing the lack of global information and shallow ***,the feature layer combines data from different sensors based on their primary and secondary importance,extracting details through small kernel convolution for primary data and obtaining global information through large kernel convolution for secondary *** experiments conducted on two-bearing fault datasets demonstrate the superiority of the two-channel convolution model,exhibiting high accuracy and robustness even in strong noise ***,it achieved an impressive 98.84%accuracy at a Signal to Noise Ratio(SNR)of−4 dB,outperforming other advanced convolutional models.

关键词： Fault diagnosis dual-data dual-channel feature fusion noise-resistance

Ros2 Real-time Performance Optimization and Evaluation

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 36-50页

作者： Yanlei Ye Zhenguo Nie Xinjun Liu Fugui Xie Zihao Li Peng Li State Key laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key lab of Precision/Ultra-Precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China

Real-time interaction with uncertain and dynamic environments is essential for robotic systems to achieve functions such as visual perception,force interaction,spatial obstacle avoidance,and motion *** ensure the reliability and determinism of system execution,a flexible real-time control system architecture and interaction algorithm are *** Ros framework was designed to improve the reusability of robotic software development by providing a distributed structure,hardware abstraction,message-passing mechanism,and application *** ecosystems for robotic development have been built around Ros1 and Ros2 architectures based on the Linux ***,because of the fairness scheduling principle of the default Linux system design and the complexity of the kernel,the system does not have real-time *** achieve a balance between real-time and non-real-time computing,this paper uses the transmission mechanism of Ros2,combines it with the scheduling mechanism of the Linux operating system,and uses Preempt_RT to enhance the real-time computing of Ros1 and *** real-time performance evaluation of Ros1 and Ros2 is conducted from multiple perspectives,including throughput,transmission mode,Qos service quality,frequency,number of subscription nodes and EtherCAT *** paper makes two significant contributions:firstly,it employs Preempt_RT to optimize the native Ros2 system,effectively enhancing the real-time performance of native Ros2 message transmission;secondly,it conducts a comprehensive evaluation of the real-time performance of both native and optimized Ros2 *** comparison elucidates the benefits of the optimized Ros2 architecture regarding real-time performance,with results vividly demonstrated through illustrative figures.

关键词： Ros Real-time system optimization Preempt_RT Real-time performance evaluation of Ros2

内蒙古阿鲁科尔沁旗敖仑花斑岩铜钼矿床成矿时代和流体包裹体研究

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岩石学报 2009年第10期25卷 2601-2614页

作者：舒启海蒋林赖勇鲁颖淮 Peking Univ Key Lab Orogen & Crust Evolut Beijing 100871 Peoples R China

内蒙古阿鲁科尔沁旗敖仑花铜钼矿床位于华北克拉通北缘西拉沐伦钼矿带,是典型的斑岩型铜钼矿床。对6件辉钼矿样品进行了铼-锇同位素分析,获得的等时线年龄为129.4±3.4Ma,表明成矿作用发生在早白垩世。根据成矿中的流体过程可分为三个阶... 详细信息

内蒙古阿鲁科尔沁旗敖仑花铜钼矿床位于华北克拉通北缘西拉沐伦钼矿带,是典型的斑岩型铜钼矿床。对6件辉钼矿样品进行了铼-锇同位素分析,获得的等时线年龄为129.4±3.4Ma,表明成矿作用发生在早白垩世。根据成矿中的流体过程可分为三个阶段:早阶段以发育石英-黄铁矿脉为标志,中阶段是主要的成矿阶段,以发育石英-多金属硫化物脉为标志。这两个阶段的流体包裹体均一温度分别集中在330～430℃和250～350℃,盐度分别为1.06～>58.41 wt%NaCl eqv和0.88wt%～48.21 wt%NaCl eqv,两个阶段均为多种类型包裹体密切共生,均一温度接近而盐度相差悬殊,且两个阶段的包裹体均一方式多样,这些特征指示了这两个阶段的流体皆发生过沸腾作用。晚阶段以发育石英-碳酸盐细脉为标志,只有少量黄铁矿沉淀,该阶段仅发育富液相包裹体,均一温度<270℃.盐度低,范围为0.71 wt%～8.41 wt%NaCl eqv。激光拉曼光谱分析表明,早、中阶段包裹体的气相成分为H_2O和CO_2,而晚阶段气相中只含H_2O。总体来看,初始流体可能直接来自岩浆房中岩浆流体的上涌,具有高温、高盐度、高氧逸度和富CO_2等特点,在430℃和350℃时流体发生了两次沸腾作用,致使成矿物质快速沉淀,流体氧逸度降低,CO_2逃逸,到了晚期,流体包裹体中基本不再含有子晶和CO_2。

关键词：内蒙古阿鲁科尔沁旗斑岩铜钼矿床成矿时代流体包裹体 Area study 均一温度盐度沸腾作用发育华北克拉通北缘氧逸度石英激光拉曼光谱黄铁矿多金属硫化物 NaCl 同位素分析

Design and experiment of corn low damage threshing device based on DEM

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International Journal of Agricultural and Biological Engineering 2023年第3期16卷 55-63页

作者： Xiaoyu Li Yuefeng Du Enrong Mao Yan’an Zhang Lei Liu Dafang Guo Beijing Key lab Optimized Design for Modern Agricultural Equipment China Agricultural UniversityBeijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China

kernel broken rate is an important index to evaluate the maize kernel direct harvesting *** view of the problem of the high kernel broken rate in the present maize harvester,a new threshing cylinder was designed in this *** device utilized rasp bar to achieve low damaged maize ears *** order to determine the structure and working parameters of threshing device,the“crop-crop”contact model and the“crop-mechanical”interaction system were established and analyzed based on the discrete element method first,and the mathematical expressions of the related kinematic response of maize kernel under the external force were ***,the structure parameters of rasp bar were studied through EDEM simulation experiment,and the working parameters were determined through test-bed ***,the simulation experiment results and test-bed experiment results were verified through field *** results showed that when the threshing cylinder speed was 356 r/min,the concave clearance was 40 mm,the installation distance of rasp bar was 250 mm with 50Mn steel,and the feeding amount was 8 kg/s,the kernel broken rate was 1.93%,which satisfied the requirements of maize harvest *** study proved that the DEM(Discrete Element Method)can be adopted to guide the optimization design of mechanical structure,and it has certain value for the research and development of operation equipment of other agricultural crops.

关键词： DEM maize threshing low damage harvesting kernel broken rate simulation

Identifcation of large-scale goaf instability in underground mine using particle swarm optimization and support vector machine

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International Journal of Mining Science and Technology 2013年第5期23卷 701-707页

作者： Zhou Jian Li Xibing Hani S.Mitri Wang Shiming Wei Wei School of Resources and Safety Engineering Central South University Hunan Key lab of Resources Exploitation and Hazard Control for Deep Metal Mines Department of Mining and Materials Engineering McGill University

An approach which combines particle swarm optimization and support vector machine(PSO–SVM)is proposed to forecast large-scale goaf instability(LSGI).Firstly,influencing factors of goaf safety are analyzed,and following parameters were selected as evaluation indexes in the LSGI:uniaxial compressive strength(UCS)of rock,elastic modulus(E)of rock,rock quality designation(RQD),area ration of pillar(Sp),the ratio of width to height of the pillar(w/h),depth of ore body(H),volume of goaf(V),dip of ore body(a)and area of goaf(Sg).Then LSGI forecasting model by PSO-SVM was established according to the influencing *** performance of hybrid model(PSO+SVM=PSO–SVM)has been compared with the grid search method of support vector machine(GSM–SVM)*** actual data of 40 goafs are applied to research the forecasting ability of the proposed method,and two cases of underground mine are also validated by the proposed *** results indicated that the heuristic algorithm of PSO can speed up the SVM parameter optimization search,and the predictive ability of the PSO–SVM model with the RBF kernel function is acceptable and robust,which might hold a high potential to become a useful tool in goaf risky prediction research.

关键词： Goaf Risk identifcation Underground mine Prediction Particle swarm optimization Support vector machine