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Synergetic effect of TeMo_5O_(16) and MoO_3 phases in MoTeO_x catalysts used for the partial oxidation of propylene

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Journal of Natural Gas Chemistry 2011年第3期20卷 249-255页

作者： yiming he Ying Wu Weizheng Weng Huilin Wan Department of Materials Physics Zhejiang Normal University Jinhua 321004 Zhejiang China State Key Laboratory for Physical Chemistry of the Solid Surfaces Xiamen University Xiamen 361005 Fujian China Institute of Physical Chemistry Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces Zhejiang Normal University Jinhua 321004 Zhejiang China

A detailed study on the synergetic effect of TeMo5O16 and MoO3 phases in the MoTeOx catalysts for the partial oxidation of propylene to acrolein has been reported in this work. It was found that both propylene conversion and acrolein selectivity increased with the addition of MoO3 to TeMo5O16. Based on the results of N2 adsorption-desorption, XRD, XPS, in-situ XRD, O2-TPO, and 2-propanol decomposition reaction, the higher catalytic performance and synergetic effect could be attributed to the enhancement of acidity and the oxygen transfer from TeMo5O16 to MoO3 phase.

关键词： synergy TeMO5O16 MoO3 acidity oxygen transfer

ENERGY CONSERVATION FOR SOLUTIONS OF INCOMPRESSIBLE VISCOELASTIC FLUIDS

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Acta Mathematica Scientia 2021年第4期41卷 1287-1301页

作者： yiming he Ruizhao ZI School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China School of Mathematics and Statistics&Hubei Key Laboratory of Mathematical Sciences Central China Normal UniversityWuhan 430079China

Some sufficient conditions of the energy conservation for weak solutions of incompressible viscoelastic flows are given in this ***,for a periodic domain in R^(3),and the coefficient of viscosity μ=0,energy conservation is proved for u and F in certain Besovs ***,in the whole space R^(3),it is shown that the conditions on the velocity u and the deformation tensor F can be relaxed,that is,u∈B_(3,c(N))^(1/3),and F∈B_(3,∞)^(1/3).Finally,when μ>0,in a periodic domain in R^(d) again,a result independent of the spacial dimension is *** precisely,it is shown that the energy is conserved for u∈L^(T)(0,T;L^(n)(Ω))for any 1/r+1/s≤1/2,with s≥4,and F∈L^(m)(0,T;L^(n)(Ω))for any 1/m+1/n≤1/2,with n≥4.

关键词： Incompressible viscoelastic fluids weak solutions energy conservation

Cu-doped Bi/Bi_(2)WO_(6) catalysts for efficient N_(2) fixation by photocatalysis

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1412-1422页

作者： Xiaojing Li Chunran Zhao Junfeng Wang Jiayu Zhang Ying Wu yiming he Department of Materials Science and Engineering Zhejiang Normal UniversityJinhua 321004China Key Laboratory of Solid State Optoelectronic Devices of Zhejiang province Zhejiang Normal UniversityJinhua 321004China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

In this paper,Cu-doped Bi_(2)WO_(6)was synthesized via a solvothermal method and applied it in photocatalytic N_(2)*** results showed the presence of a small amount of metallic Bi in the photocatalyst,indicating that the synthesized photocatalyst is actually Bi/Cu-Bi_(2)WO_(6)*** doped Cu had a valence state of+2 and most likely substituted the position of Bi^(3+).The introduced Cu did not affect the metallic Bi content,but mainly influenced the energy band structure of Bi_(2)WO_(6).The band gap was slightly narrowed,the conduction band was elevated,and the work function was *** reduced work function improved the transfer and separation of charge carriers,which mainly caused the increased *** optimized NH_(3)generation rates of Bi/Cu-Bi_(2)WO_(6)reached 624 and 243μmol·L^(-1)·g^(-1)·h^(-1)under simulated solar and visible light,and these values were approximately 2.8 and 5.9 times higher those of Bi/Bi_(2)WO_(6),*** research provides a method for improving the photocatalytic N_(2)fixation and may provide more information on the design and preparation of heteroatom-doped semiconductor photocatalysts for N_(2)-to-NH_(3)conversion.

关键词： Bi_(2)WO_(6) Cu doping work function photocatalytic N_(2)fixation charge separation

Recommendation System Based on Spark and Hybrid Weight Algorithm

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Recommendation System Based on Spark and Hybrid Weight Algor...

作者： yiming he 华中师范大学

学位级别：硕士

The development of Internet technology is changing with each passing *** used to worry about lack of *** they face huge amounts of information but it is difficult to get useful ***'s worry has changed from the lack of information to how to obtain the valuable information they need in the sea of *** emergence of the recommendation system solves the problem of information overload to some *** the initial single algorithm recommendation system to the later traditional weight mixing system,the recommendation system has developed very rapidly,and has mature applications in the fields of e-commerce and news *** traditional weight hybrid algorithm system often has better performance than the single algorithm recommendation *** weight parameters of traditional hybrid recommendation systems are usually obtained by researchers' experience or through a lot of *** the increase of data,the requirements of parameter accuracy and efficiency are gradually improved,and the previous parameter setting methods are gradually unable to meet accuracy and ***,in the face of massive data,traditional data distribution platforms often have the disadvantage of too long training time due to a large amount of I/O *** the traditional backup fault-tolerant design wastes a lot of ***,the problems of data sparsity,cold start of the system and unsatisfactory prediction accuracy still *** on the inconsistent bias of different recommendation algorithms and the introduction of Spark,a new generation of distributed big data computing platform,this paper implements a new hybrid algorithm recommendation system to achieve more efficient and accurate *** main work and innovation points of paper are as follows:(1)This paper designs and implements a new weight calculation method,and the weight is assigned according to the bias of each algorithm,which can well alleviate the a

关键词： Mixed Recommendation System Collaborative Filtering Latent Factor Modle Spark

Adversarial Defense Technology for Small Infrared Targets

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Computers, Materials & Continua 2024年第10期81卷 1235-1250页

作者： Tongan Yu Yali Xue yiming he Shan Cui Jun Hong College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing210000China Shanghai Electro-Mechanical Engineering Institute Shanghai201109China

With the rapid development of deep learning-based detection algorithms,deep learning is widely used in the field of infrared small target ***,well-designed adversarial samples can fool human visual perception,directly causing a serious decline in the detection quality of the recognition *** this paper,an adversarial defense technology for small infrared targets is proposed to improve model *** adversarial samples with strong migration can not only improve the generalization of defense technology,but also save the training ***,this study adopts the concept of maximizing multidimensional feature distortion,applying noise to clean samples to serve as subsequent training *** this basis,this study proposes an inverse perturbation elimination method based on Generative Adversarial Networks(GAN)to realize the adversarial defense,and design the generator and discriminator for infrared small targets,aiming to make both of them compete with each other to continuously improve the performance of the model,find out the commonalities and differences between the adversarial samples and the original *** experimental verification,our defense algorithm is not only able to cope with multiple attacks but also performs well on different recognition models compared to commonly used defense algorithms,making it a plug-and-play efficient adversarial defense technique.

关键词： Adversarial defense adversarial robustness small infrared targets transferable perturbation GAN

De Novo Assembly Methods for Next Generation Sequencing Data

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Tsinghua Science and Technology 2013年第5期18卷 500-514页

作者： yiming he Zhen Zhang Xiaoqing Peng Fangxiang Wu Jianxin Wang the School of Information Science and Engineering Central South University the Morehouse School of Medicine the Department of Mechanical Engineering and Division of Biomedical Engineering University of Saskatchewan

The recent breakthroughs in next-generation sequencing technologies, such as those of Roche 454,Illumina/Solexa, and ABI SOLID, have dramatically reduced the cost of producing short reads of the genome of new species. The huge volume of reads, along with short read length, high coverage, and sequencing errors, poses a great challenge to de novo genome assembly. However, the paired-end information provides a new solution to these problems. In this paper, we review and compare some current assembly tools, including Newbler, CAP3, Velvet,SOAPdenovo, AllPaths, Abyss, IDBA, PE-Assembly, and Telescoper. In general, we compare the seed extension and graph-based methods that use the overlap/lapout/consensus approach and the de Bruijn graph approach for assembly. At the end of the paper, we summarize these methods and discuss the future directions of genome assembly.

关键词： next-generation sequencing genome assembly overlap/lapout/consensus de Bruijn graph

Harmonic reducer in-situ fault diagnosis for industrial robots based on deep learning

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Science China(Technological Sciences) 2022年第9期65卷 2116-2126页

作者： ZHOU Xing ZHOU HuiCheng he yiming HUANG ShiFeng ZHU ZhiHong CheN JiHong School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Foshan Institute of Intelligent Equipment Technology Foshan 528234China

The harmonic reducer is an essential kinetic transmission component in the industrial *** is easy to be fatigued and resulted in physical malfunction after a long period of ***,an accurate in-situ fault diagnosis for the harmonic reducers in an industrial robot is especially *** paper proposes a fault diagnosis method based on deep learning for the harmonic reducer of industrial robots via consecutive time-domain vibration *** the sampling signals from industrial robots are long,narrow,and channel-independent,this method combined a 1-dimensional convolutional neural network with matrix kernels(1-D MCNN)adaptive *** adjusting the size of the convolution kernels,it can concentrate on the contextual feature extraction of consecutive time-domain data while retaining the ability to process the multi-channel fusion *** proposed method is examined on a physical industrial robot platform,which has achieved a prediction accuracy of99%.Its performance is appeared to be superior in comparison to the traditional 2-dimensional CNN,deep sparse automatic encoding network(DSAE),multilayer perceptual network(MLP),and support vector machine(SVM).

关键词： harmonic reducer industrial robots fault diagnosis convolutional neural network(CNN)

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In situ preparation of g-C3N4/Bi4O5I2 complex and its elevated photoactivity in Methyl Orange degradation under visible light

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Journal of Environmental Sciences 2020年第1期32卷 149-162页

作者： Zhe Feng Lin Zeng Qingle Zhang Shifeng Ge Xinyue Zhao Hongjun Lin yiming he Department of Materials Science and Engineering Zhejiang Normal UniversityJinhua 321004China College of Chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

A graphite carbon nitride(g-C3N4)modified Bi4O5I2 composite was successfully prepared insitu via the thermal treatment of a g-C3N4/Bi OI precursor at 400°C for 3 *** as-prepared g-C3N4/Bi4O5I2 showed high photocatalytic performance in Methyl Orange(MO)degradation under visible *** best sample presented a degradation rate of 0.164 min^-1,which is 3.2 and 82 times as high as that of Bi4O5I2 and g-C3N4,*** g-C3N4/Bi4O5I2 was characterized by X-ray powder diffractometer(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman,X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectra(DRS),electrochemical impedance spectroscopy(EIS)and transient photocurrent response in order to explain the enhanced *** indicated that the decoration with a small amount of g-C3N4 influenced the specific surface area only ***,the capability for absorbing visible light was improved measurably,which was beneficial to the MO *** top of that,a strong interaction between g-C3N4 and Bi4O5I2 was *** interplay promoted the formation of a favorable heterojunction structure and thereby enhanced the charge ***,the g-C3N4/Bi4O5I2 composite presented greater charge separation efficiency and much better photocatalytic performance than ***,g-C3N4/Bi4O5I2 also presented high stability.·O2^- and holes were verified to be the main reactive species.

关键词： g-C3N4 Bi4O5I2 Methyl Orange degradation heterojunction Visible light

Decoration of CdMoO_(4) micron polyhedron with Pt nanoparticle and their enhanced photocatalytic performance in N_(2) fixation and water purification

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 1949-1961页

作者： Xujie Ren Junfeng Wang Shude Yuan Chunran Zhao Lin Yue Zhihao Zeng yiming he Department of Materials Science and Engineering Zhejiang Normal UniversityJinhua 321004China Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province Zhejiang Normal UniversityJinhua 321004China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China

This study aimed to prepare and apply a novel Pt/CdMoO_(4) composite photocatalyst for photocatalytic N2 fixation and tetracycline degradation. The Pt/CdMoO_(4) composite was subjected to comprehensive investigation on the morphology, structure, optical properties, and photoelectric chemical properties. The results demonstrate the dispersion of Pt nanoparticles on the CdMoO_(4) surface. Close contact between CdMoO_(4) and Pt was observed, resulting in the formation of a heterojunction structure at their contact region. Density functional theory calculation and Mott-Schottky analysis revealed that Pt possesses a higher work function value than CdMoO_(4), resulting in electron drift from CdMoO_(4) to Pt and the formation of a Schottky barrier. The presence of this barrier increases the separation efficiency of electron-hole pairs, thereby improving the performance of the Pt/CdMoO_(4) composite in photocatalysis. When exposed to simulated sunlight, the optimal Pt/CdMoO_(4) catalyst displayed a photocatalytic nitrogen fixation rate of 443.7 μmol·L‒^(1)·g‒^(1)·h‒^(1), which is 3.2 times higher than that of pure CdMoO_(4). In addition, the composite also exhibited excellent performance in tetracycline degradation, with hole and superoxide species identified as the primary reactive species. These findings offer practical insights into designing and synthesizing efficient photocatalysts for photocatalytic nitrogen fixation and antibiotics removal.

关键词： photocatalytic N2 fixation Pt CdMoO4 tetracycline degradation Schottky barrier