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Magnéli phases TinO2n-1 as novel ozonation catalysts for effective mineralization of phenol

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1978-1984页

作者： Xian mao Fanglu yuan Anqi Zhou Wenheng Jing State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for special Separation Membrane College of Chemical EngineeringNanjing Tech UniversityNanjing210009China

Magnéli phases TinO2n-1 have been demonstrated as promising environmentally friendly materials in advanced oxidation *** this study,Magnéli phases TinO2n-1 have been used as catalysts for the ozonation of phenol in aqueous solution for the first *** materials exhibited excellent catalytic ozonation activities both in phenol degradation and *** Ti4O7was added,the reaction rate was six-fold higher than that of with ozone alone,while the total organic carbon removal rate was substantially elevated from around 19.2%to 92%.By virtue of the good chemical stability of the materials,a low metal leaching of less than 0.15 mg·L^-1could effectively avoid the secondary pollution by metal *** quenching tests revealed·O2^-and ^1O2to be active oxygen species for phenol degradation at p H *** semiconductor catalysts,TinO2n-1 materials show electronic transfer *** adsorbed at B-acid sites of the catalyst surface can capture an electron from the conversion of Ti（Ⅲ）to Ti（Ⅳ）,and is thereby broken into the active oxygen *** was interesting to observe that TinO2n-1 exhibit better catalytic activity for phenol degradation and mineralization with lower n *** difference in electrical conductivity can be considered as a major factor for the catalytic *** highly conductive catalysts show a faster electron-transfer rate and better catalytic ***,significant evidences have been obtained for a single-electron-transfer mechanism of catalytic ozonation with Magnéli phases TinO2n-1.

关键词： TinO2n-1 Catalytic ozonation Conductivity B-acid sites Single-etectron-transfer

Method of moving target detection based on sub-image cancellation for single-antenna airborne synthetic aperture radar

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Journal of Systems Engineering and Electronics 2007年第3期18卷 448-453页

作者： Liu Shujun yuan Yunneng Gao Fei mao Shiyi Dept. of Electronic and Information Engineering Beihang Univ. Beijing 100083 P. R. China

The method of moving target detection based on subimage cancellation for single-antenna airborne SAR is presented. First the subimage is obtained through frequency processing is pointed out. The imaging difference of a stationary objects and moving object in the subimage based on the frequency division is analyzed from the fundamental principle. Then the developed method combines the shear averaging algorithm to focus on the moving target in the subimage, after the clutter suppression and the focusing position in each subimage is obtained. Next the observation model and the relative movement of the moving targets between the subimages estimate the moving targets. The theoretical analysis and simulation results demonstrate that the method is effective and can not only detect the moving targets, but also estimate their motion parameters precisely.

关键词： synthetic aperture radar moving target detection sub-image cancellation parameter estimation.

Solar flare forecasting based on a Fusion Model

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Earth and Planetary Physics 2025年第1期9卷 171-181页

作者： YiYang Li ShiYong Huang SiBo Xu ZhiGang yuan Kui Jiang QiYang Xiong RenTong Lin School of Earth and Space Science Technology Hubei Luojia LaboratoryWuhan UniversityWuhan 430072China

Solar flare prediction is an important subject in the field of space *** learning technology has greatly promoted the development of this *** this study,we propose a novel solar flare forecasting model integrating Deep Residual Network(ResNet)and Support Vector Machine(SVM)for both≥C-class(C,M,and X classes)and≥M-class(M and X classes)*** collected samples of magnetograms from May 1,2010 to September 13,2018 from Space-weather Helioseismic and Magnetic Imager(HMI)Active Region Patches and then used a cross-validation method to obtain seven independent data *** then utilized five metrics to evaluate our fusion model,based on intermediate-output extracted by ResNet and SVM using the Gaussian kernel *** results show that the primary metric true skill statistics(TSS)achieves a value of 0.708±0.027 for≥C-class prediction,and of 0.758±0.042 for≥M-class prediction;these values indicate that our approach performs significantly better than those of previous *** metrics of our fusion model’s performance on the seven datasets indicate that the model is quite stable and robust,suggesting that fusion models that integrate an excellent baseline network with SVM can achieve improved performance in solar flare ***,we also discuss the performance impact of architectural innovation in our fusion model.

关键词： solar flare pace weather deep learning Fusion Model

Partitioning the effects of environmental and spatial heterogeneity on distribution of plant diversity in the Yellow River Estuary

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Science China(Life Sciences) 2012年第6期55卷 542-550页

作者： yuan xiu MA KeMing WANG De State Key Laboratory of Urban&Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Graduate University of Chinese Academy of Sciences Beijing 100049China yantai Institute of Coastal Zone Chinese Academy of SciencesYantai 264003China

For successful conservation and restoration of biodiversity,it is important to understand how diversity is *** the ecological research community,a current topic of interest is how much of the variation in plant species richness and composition is explained by environmental variation(niche-based model),relative to spatial processes(neutral theory).The Yellow River Estuary(YRE) is a newly formed and fragile wetland ecosystem influenced by both the Yellow River and Bohai ***,we applied variance partitioning techniques to assess the relative effects of spatial and environmental variables on species richness and composition in the *** also conducted a species indicator analysis to identify characteristic species for three subestuaries within the *** redundancy analysis showed that the variations in species richness and composition were explained by both environmental and spatial *** majority of explained variation in species richness and composition was attributable to local environmental *** the environmental variables,soil salinity made the greatest contribution to species abundance and *** salinity was the most important factor in the Diaokou subestuary,while soil moisture was the most important factor influencing species richness in the Qingshui and Chahe *** combined effects of soil salinity and moisture determined species richness and composition in the *** results increase our understanding of the organization and assembly of estuarine plant communities.

关键词： environment spatial variation species composition species richness variation partitioning

The Arabidopsis LFR Gene Is Required for the Formation of Anther Cell Layers and Normal Expression of Key Regulatory Genes

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Molecular Plant 2012年第5期5卷 993-1000页

作者： xiu-Tang Wang Can yuan Ting-Ting yuan Su-Juan Cui Key Laboratory of Molecular Cell Biology in Hebei Province College of Life Science Hebei Normal University Shijiazhuang 050016 China

The anther is the male reproductive organ in flowering plants. Although some genes were reported to be involved in anther development, the molecular mechanisms underlying the transcriptional regulation of these genes is unclear. Ifr-2 （leaf and flower related-2）, the null allele of Arabidopsis thaliana LFR （LEAF AND FLOWER RELATED）, was male-sterile. The anthers of Ifr-2 plants were defective in sporogenous cell formation, tapetum development, and pollen development. In agreement with these phenotypes, expression studies showed that LFR was expressed in all cell layers of the anther, and that expression was particularly strong in the tapetal cells and pollen grains, Quantitative RT-PCR analysis revealed that LFR is required for the normal transcription of some anther development-related genes, such as AMS, CALS5, and DYT1, MS1 and MS2, and ROXY2. Genetic analysis showed that SPL was epistatic to LFR while LFR was epistatic to DYT1. We propose that LFR may be a crucial component in the regulation of a genetic network that modulates anther development.

关键词： cell differentiation/specialization gene expression gene regulation genetics reproductive biology Arabidopsis.

A Note on the Left Essential Spectra of Operator Matrices

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2235-2240页

作者： yuan LI xiu Hong SUN Hong Ke DU College of Mathematics and Information Science Shaanxi Normal University Xi'an 710062 P. R. China Department of Basic Courses Xi'an University of Science and Technology Xi'an 710054 P. R. China College of Mathematics and Information Science Shaanxi Normal University Xi'an 710062 P. R China

When A ∈ B（H） and B ∈ B（K） are given, we denote by Me the operator matrix acting on the infinite dimensional separable Hilbert space H ＋ K of the form Me = （ A C O B）. In this paper, a necessary and sufficient condition for Me to be left Fredholm for some C ∈ F（K, H）（C ∈ Inv（K, H）） is given, where F（K,H） and Inv（K, H） denote respectively, the set of Fredholm operators and the set of invertible operators of B（K, H）. In addition, we give a necessary and sufficient condition for Me to be left Fredholm for all C ∈ Inv（K, H）.

关键词： left essential spectrum 2×2 operator matrix perturbations of spectra

Dust-Acoustic Soliton in a Streaming Plasma

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Chinese Physics Letters 1997年第6期14卷 432-435页

作者： LIU Jin-yuan MA Jin-xiu Department of Modern Physics University of Science and Technology of ChinaHefei 230027

Large amplitude dust-acoustic solitons in a plasma with ion streaming are investigated on a very slow time scale of dust motion with variable grain *** is found that both compressional and rarefactive solitons can coe... 详细信息

关键词： solitons soliton rare

Ladle Furnace Liquid Steel Temperature Prediction Model Based on Optimally Pruned Bagging

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Journal of Iron and Steel Research International 2012年第12期19卷 21-28页

作者： LU Wu mao Zhi-zhong yuan Ping College of Information Science and Engineering Northeastern University Shenyang 110004 Liaoning China State Key Laboratory of Synthetical Automation for Process Industries University Shenyang 110004 Liaoning China

For accurately forecasting the liquid steel temperature in ladle furnace （LF）, a novel temperature predic tion model based on optimally pruned Bagging combined with modified extreme learning machine （ELM） is pro posed. By analyzing the mechanism of LF thermal system, a thermal model with partial linear structure is obtained. Subsequently, modified ELM, named as partial linear extreme learning machine （PLELM）, is developed to estimate the unknown coefficients and undefined function of the thermal model. Finally, a pruning Bagging method is pro- posed to establish the aggregated prediction model for the sake of overcoming the limitation of individual predictor and further improving the prediction performance. In the pruning procedure, AdaBoost is adopted to modify the ag- gregation order of the original Bagging ensembles, and a novel early stopping rule is designed to terminate the aggre- gation earlier. As a result, an optimal pruned Bagging ensemble is achieved, which is able to retain Bagging＇s ro- bustness against highly influential points, reduce the storage needs as well as speed up the computing time. The pro- posed prediction model is examined by practical data, and comparisons with other methods demonstrate that the new ensemble predictor can improve prediction accuracy, and is usually consisted compactly.

关键词： Bagging extreme learning machine LF liquid steel temperature prediction model AdaBoost

Recent studies on potential accident-tolerant fuel-cladding systems in light water reactors

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Nuclear Science and Techniques 2020年第3期31卷 94-123页

作者： Sheng-Li Chen xiu-Jie He Cen-Xi yuan Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Universite Grenoble Alpes I-MEP238402 Saint Martin d’HeresFrance

Accident-tolerant fuel(ATF)has attracted considerable research attention since the 2011 Fukushima nuclear *** improve the accident tolerance of the fuel-cladding systems in the current light-water reactors,it is proposed to develop and deploy(1)an enhanced Zrbased alloy or coated zircaloy for the fuel cladding,(2)alternative cladding materials with better accident tolerance,and(3)alternative fuels with enhanced accident tolerance and/or a higher U *** review presents the features of the current UO2-zircaloy *** techniques and characters to develop coating materials and enhanced Zr-based alloys are *** features of several selected alternative fuels and cladding materials are reviewed and *** neutronic evaluations of alternative fuel-cladding systems are *** is expected that one or more types of ATF-cladding systems discussed in the present review will be implemented in commercial reactors.

关键词： Accident-tolerant fuel Accident-tolerant cladding Light-water reactor Neutronic evaluation