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Insect Science 2012年第1期19卷 13-20页

作者： Min Yang Jin-cai Wu hai-Nan Gu School of Plant Protection Yangzhou UniversityYangzhouChina Indooroopilly Science Centre Department of Primary Industries and FisheriesQueensland 4068Australia

The current study investigated changes in the content of the rare earth element Europium （Eu） in roots, shoots and leaves of rice plants and in Nilaparvata lugens Stal （Hemiptera： Delphacidae） using an Eu marker and hydroponic culture. The results showed that N. lugens infestation significantly reduced Eu content in roots, shoots and leaves of two rice varieties, Shenyou 1 and Xieyou 963. The Eu content in roots, shoots and leaves of the susceptible variety, Shenyou 1, was significantly higher than that in the resistant variety, Xieyou 963. The Eu content ofN. lugens fed on Shenyou 1 was significantly higher than of those fed on Xieyou 963. In addition, the Eu level was elevated at a higher density ofN. lugens infestation. Eu content in the bodies ofN. lugens was related to their weight and honeydew excretion, with a significant positive correlation. Thus, Eu content in the bodies ofN. lugens can be considered an index of the amount of phloem sap taken in by N. lugens because the amount of honeydew excretion is proportional to the amount of phloem sap consumed. The ratios of Eu content in N. lugens to that in roots, shoots and leaves of rice plants were elevated at a higher N. lugens infestation density. That ratio was maximal in leaves, was intermediate in shoots and was minimal in roots. There was no significant difference in ratios between the two plant varieties. An Eu marker may be useful in the screening of resistant varieties and in the study of the mechanisms of resistance.

关键词： markers Nilaparvata lugens rare earth element Eu rice

A Novel Hexanordammarane Glycoside from the Roots of Panax notoginseng

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Chinese Chemical Letters 2001年第1期12卷 59-62页

作者： hai Zhou LI Rong Wei TENG chong Ren YANG Kunming Institute of Botany Chinese Academy of SciencesKunming 650204

Notoginsenoside R-111, a novel hexanordammarane glycoside was isolated from the roots of Panax nototginseng, as a minor constituent. Its structure was determined as 6-O-(beta -D-glucopyranosyl)-3 beta ,6 alpha ,12 bet... 详细信息

关键词： notoginsenoside R-10 nortriterpenoid saponin Panax notoginseng

Vehicle Detection Based on Visual Saliency and Deep Sparse Convolution Hierarchical Model

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 765-772页

作者： cai Yingfeng WANG hai CHEN Xiaobo GAO Li CHEN Long Automotive Engineering Research Institute Jiangsu University School of Automotive and Traffic Engineering Jiangsu University

Traditional vehicle detection algorithms use traverse search based vehicle candidate generation and hand crafted based classifier training for vehicle candidate *** types of methods generally have high processing times and low vehicle detection *** address this issue,a visual saliency and deep sparse convolution hierarchical model based vehicle detection algorithm is proposed.A visual saliency calculation is firstly used to generate a small vehicle candidate *** vehicle candidate sub images are then loaded into a sparse deep convolution hierarchical model with an SVM-based classifier to perform the final *** experimental results demonstrate that the proposed method is with 94.81% correct rate and 0.78% false detection rate on the existing datasets and the real road pictures captured by our group,which outperforms the existing state-of-the-art *** importantly,high discriminative multi-scale features are generated by deep sparse convolution network which has broad application prospects in target recognition in the field of intelligent vehicle.

关键词： vehicle detection visual saliency deep model convolution neural network

基于太赫兹-热重光谱的粘土矿物热解特性表征

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光谱学与光谱分析 2025年第1期45卷 179-182页

作者：栗欣妤刘彩琴黄昊翀郑志远张自力邱昆峰中国地质大学(北京)数理学院北京100083 中国地质大学(北京)地球科学与资源学院北京100083

粘土矿物是粘土岩和土壤的重要组成部分,是地球表面大部分覆盖物的主要物质单元,深入研究其结构特点、粒径大小及含水量的变化等特征对探究粘土矿物富集地区的环境演变规律和矿物工业应用具有重要指导意义。面对地学领域多样化的实际应... 详细信息

粘土矿物是粘土岩和土壤的重要组成部分,是地球表面大部分覆盖物的主要物质单元,深入研究其结构特点、粒径大小及含水量的变化等特征对探究粘土矿物富集地区的环境演变规律和矿物工业应用具有重要指导意义。面对地学领域多样化的实际应用需求,常见的矿物表征方法在挖掘矿物中指针性极强的物理特性时经常受限。作为一种新型非接触式相干测试手段,太赫兹光谱技术利用该波段指纹谱、宽光谱及水敏感等众多优势特性,可对粘土矿物进行无损探测并获得振幅和相位等光学信息,从而区分其晶体结构及成分组成。本文以太赫兹时域光谱技术为主要手段,同时结合热重分析和傅里叶红外光谱技术对粘土矿物的热解特性展开一系列研究。其中,高岭土作为重要原料,其成分组成、粒径大小及煅烧产物都会影响陶瓷质量。实验结果证实不同状态的高岭土在太赫兹波段下的吸收系数和折射率等光学参数会发生明显变化。结构单元为2∶1型层状硅酸盐的滑石和叶腊石因其晶体结构中八面体阳离子的不同,使得光谱差异明显,这很好地反映出典型呈电中性含水矿物的热解产物及含水量指标。值得一提的是,与太赫兹领域的传统认知不同,除却一些化学手段干预,实验过程中发现叶腊石在1.10 THz具备特征吸收峰,该峰的出现既能帮助物质定性表征和光学器件发展,又丰富了太赫兹光谱对矿物的全面了解,为太赫兹光谱学与地学的交叉研究提供新的研究角度。

关键词：太赫兹光谱粘土矿物吸收系数热解特性

Geometry of Motion for Video Shakiness Detection

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Journal of Computer Science & Technology 2018年第3期33卷 475-486页

作者： Xiao-Qun Wu hai-Sheng Li Jian Cao Qiang cai School of Computer and Information Engineering Beijing Technology and Business University Beijing 100048 China Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business University Beijing 100048 China

This paper presents a novel algorithm for automatically detecting global shakiness in casual videos. Per-frame amplitude is computed by the geometry of motion, based on the kinematic model defined by inter-frame geometric transformations. Inspired by motion perception, we investigate the just-noticeable amplitude of shaky motion perceived by the human visual system. Then, we use the thresholding contrast strategy on the statistics of per-frame amplitudes to determine the occurrence of perceived shakiness. For testing the detection accuracy, a dataset of video clips is constructed with manual shakiness label as the ground truth. The experiments demonstrate that our algorithm can obtain good detection accuracy that is in concordance with subjective judgement on the videos in the dataset.

关键词： video shakiness kinematic model motion perception

Structural screening of phosphorus sulfur ternary hydride PSH_(6) with a high-temperature superconductivity at 130 GPa

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Frontiers of physics 2023年第2期18卷 205-211页

作者： Yu-Long hai He-Jin Yan Yong-Qing cai Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoTaipaMacaoChina

In our study,we constructed a series of inorganic nonmetallic ternary hydrides PSH6 by first-principles structural screening under pressure of 200 *** structural stability under lower pressure are *** on the structural stability,electronic and phonon properties,as well as the possible superconducting properties within the framework of Bardeen−Cooper−Schrieffer(BCS)theory,we show that PSH6 with space group possesses a superconducting transition temperature of 146 K at 130 *** the pressure range of 100−200 GPa,our work suggests that the ternary phosphorus-sulfur-hydrogen would act as a promising compositional and elemental space for achieving high-temperature superconductivity.

关键词： phosphoruses sulfur hydrides high-temperature superconductivity low-pressure structural screening

Graph Regularized L_p Smooth Non-negative Matrix Factorization for Data Representation

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 584-595页

作者： Chengcai Leng hai Zhang Guorong cai Irene Cheng Anup Basu the School of Mathematics Northwest University School of Mathematics and Information Sciences Nanchang Hangkong University Nanchang 330063 China the Department of Computing Science University of Alberta the Faculty of Information Technology & State Key Laboratory of Quality Research in Chinese Medicines Macao University of Science and Technology the College of Computer Engineering Jimei University the Department of Computing Science University of Alberta

This paper proposes a Graph regularized Lpsmooth non-negative matrix factorization(GSNMF) method by incorporating graph regularization and L_p smoothing constraint, which considers the intrinsic geometric information of a data set and produces smooth and stable solutions. The main contributions are as follows: first, graph regularization is added into NMF to discover the hidden semantics and simultaneously respect the intrinsic geometric structure information of a data set. Second,the Lpsmoothing constraint is incorporated into NMF to combine the merits of isotropic(L_2-norm) and anisotropic(L_1-norm)diffusion smoothing, and produces a smooth and more accurate solution to the optimization problem. Finally, the update rules and proof of convergence of GSNMF are given. Experiments on several data sets show that the proposed method outperforms related state-of-the-art methods.

关键词： Data clustering dimensionality reduction graph regularization Lp smooth non-negative matrix factorization(SNMF)

Preliminary Assessment of Simulations of Climate Changes over China by CMIP5 Multi-Models

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Atmospheric and Oceanic Science Letters 2012年第6期5卷 489-494页

作者： XU Ying XU chong-hai National Climate Center China Meteorological AdministrationBeijing 100081China Meteorological Observation Centre China Meteorological AdministrationBeijing 100081China Laboratory for Climate Studies China Meteorological AdministrationBeijing 100081China

Based on 18 global climate models' simulations of the 20th century climate, a set of experiments within phase five of the Coupled Model Inter-comparison Project (CMIP5), the performances of simulating the present climate over China are assessed. Compared with observations, models can capture the dominant features of the geographic distributions of temperature and precipitation during 1961-2005. For the temporal changes of temperature, models appear to have a good performance on reproducing the warming tendency but show limited skills for precipitation. For the regional mean temperature and precipitation over the whole of China, most models underestimate the actual temperature and overestimate precipitation. Concerning the standard deviations of simulations by the 18 models, they are larger for temperature in the western part of China, while the standard deviations are larger for precipitation in the South.

关键词： assessment simulation CMIP5 China

A sustainable aqueous Zn-I2 battery

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Nano Research 2018年第7期11卷 3548-3554页

作者： chong Bai Fengshi cai Lingchang Wang Shengqi Guo Xizheng Liu Zhihao Yuan School of Materials Science and Engineering Tianjin University Tianjin 300072 China School of Materials Science and Engineering Tianjin Key Lab for Photoelectric Materials & Devices Tianjin University of Technology Tianjin 300384 China

Rechargeable metal-iodine batteries are an emerging attractive electrochemical energy storage technology that combines metallic anodes with halogen cathodes. Such batteries using aqueous electrolytes represent a viable solution for the safety and cost issues associated with organic electrolytes. A hybrid-electrolyte battery architecture has been adopted in a lithium-iodine battery using a solid ceramic membrane that protects the metallic anode from contacting the aqueous electrolyte. Here we demonstrate an eco-friendly, low-cost zinc-iodine battery with an aqueous electrolyte, wherein active I2 is confined in a nanoporous carbon cloth substrate. The electrochemical reaction is confined in the nanopores as a single conversion reaction, thus avoiding the production of I3- intermediates. The cathode architecture fully utilizes the active I2, showing a capacity of 255 mAh·g^-1 and low capacity cycling fading. The battery provides an energy density of -151 Wh·kg^-1 and exhibits an ultrastable cycle life of more than 1,500 cycles.

关键词： aqueous battery nanoporous carbon iodine zinc cycle life

Effects of water application uniformity using a center pivot on winter wheat yield, water and nitrogen use efficiency in the North China Plain

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Journal of Integrative Agriculture 2020年第9期19卷 2326-2339页

作者： cai Dong-yu YAN hai-jun LI Lian-hao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083P.R.China College of Mechanical and Electronic Engineering Henan Agricultural UniversityZhengzhou 450002P.R.China

In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the grain yield, water use efficiency (WUE) and nitrogen use efficiency (NUE) have become a research hotspot. In this study, a two-year field experiment was conducted during the winter wheat growing season in 2016–2018 to evaluate the water application uniformity of a center pivot with two low pressure sprinklers (the R3000 sprinklers were installed in the first span, the corresponding treatment was RS;the D3000 sprinklers were installed in the second span, the corresponding treatment was DS) and a P85A impact sprinkler as the end gun (the corresponding treatment was EG), and to analyze its effects on grain yield, WUE and NUE. The results showed that the water application uniformity coefficients of R3000, D3000 and P85A along the radial direction of the pivot (CUH) were 87.5, 79.5 and 65%, respectively. While the uniformity coefficients along the traveling direction of the pivot (CUC) were all higher than 85%. The effects of water application uniformity of the R3000 and D3000 sprinklers on grain yield were not significant (P>0.05);however, the average grain yield of EG was significantly lower (P<0.05) than those of RS and DS, by 9.4 and 11.1% during two growing seasons, respectively. The coefficients of variation (CV) of the grain yield had a negative correlation with the uniformity coefficient. The CV of WUE was more strongly affected by the water application uniformity, compared with the WUE value, among the three treatments. The NUE of RS was higher than those of DS and EG by about 6.1 and 4.8%, respectively, but there were no significant differences in NUE among the three treatments during the two growing seasons. Although the CUH of the D3000 sprinklers was lower than that of the R3000, it had only limited effects on the grain yield, WUE and NUE. However

关键词： center pivot low pressure sprinkler water application uniformity winter wheat water and nitrogen use efficiency