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Unveiling spin magnetic effect of TM doped SnS_(2) nanosheet with enhanced hydrogen evolution reaction

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Journal of Energy Chemistry 2024年第12期99卷 636-644页

作者： Ruixin Xu Tianzhao lin Shiqian Cao Tingting bo Yanyu liu Wei Zhou Department of Applied Physics Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing TechnologySchool of ScienceTianjin UniversityTianjin 300072China College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China

Photoelectrochemical hydrogen evolution reaction(HER)is taken into account as an alternative to effective hydrogen production,emphasizing the importance of *** magnetism of catalysts could modulate the adsorption of the H atom and further enhance the HER ***,doping the double transition metal atoms on SnS_(2) nanosheet(TM_(2)@SnS_(2))to form the efficient magnetic catalyst is proposed to explore the spin magnetic effect on the HER *** performing first-principles calculations,nonmagnetic V_(2)@SnS_(2) is proved to be the candidate of the HER catalyst;nevertheless,the HER activities of antiferromagnetic and ferromagnetic V_(2)@SnS_(2) are relatively inferior due to the spin-induced charge ***,machine learning analysis shows the absolute importance of the electronic structure of TM dopants and surrounding S ligands,and the HER activity could be predicted by the modified band centers of S-3p_(z) and ***,the proof-of-concept experiment has substantiated the above theoretical predictions by significantly increasing liner sweep voltammetry and photocurrent with applied magnetic *** work provides a new avenue for uncovering the spin catalytic mechanism and the exploration and design of efficient HER catalysts.

关键词： Density functional theory Hydrogen evolution reaction Tin sulfide Transition metal doping Machine learning

Memory-enhanced text style transfer with dynamic style learning and calibration

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Science China(Information Sciences) 2024年第4期67卷 181-196页

作者： Fuqiang lin Yiping SONG Zhiliang TIAN Wangqun CHEN Diwen DONG bo liu College of Computer Science and Technology National University of Defense Technology Department of Computer Science and Engineering The Hong Kong University of Science and Technology Strategic Assessments and Consultation Institute Academy of Military Sciences

Text style transfer aims to rephrase a sentence to match the desired style while retaining the original content. As a controllable text generation task, mainstream approaches use content-independent style embedding as control variables to guide stylistic generation. Nonetheless, stylistic properties are contextsensitive even under the same style. For example, “delicious” and “helpful” convey positive sentiments,although they are more likely to describe food and people, respectively. Therefore, desired style signals must vary with the content. To this end, we propose a memory-enhanced transfer method, which learns fine-grained style representation concerning content to assist transfer. Rather than employing static style embedding or latent variables, our method abstracts linguistic characteristics from training corpora and memorizes subdivided content with the corresponding style representations. The style signal is dynamically retrieved from memory using the content as a query, providing a more expressive and flexible latent style space. To address the imbalance between quantity and quality in different content, we further introduce a calibration method to augment memory construction by modeling the relationship between candidate *** results obtained using three benchmark datasets confirm the superior performance of our model compared to competitive approaches. The evaluation metrics and case study also indicate that our model can generate diverse stylistic phrases matching context.

关键词： style transfer memory-enhanced method text generation deep learning text representation

Measured overall effusion cooling effectiveness over a wide blowing ratio range using infrared imaging

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航空动力学报 2010年第7期25卷 1454-1463页

作者： ZHANG Chi SONG bo lin Yu-zhen XU Quan-hong liu Yan National Key Laboratory of Science and Technology on Aero-Engines School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China Jiangsu Chinfan Compressor Incorporation Changshu Economic Development Zone Jiangsu 215513 China China North Vehicle Research Institute China North Industries Group Corporation Beijing 100072 China

Experimental investigations were performed on the overall cooling effectiveness η of a flat effusion wall over a wide range of blowing ratio(M=0.47～5.27).The effusion wall had a staggered multi-hole pattern typical of gas turbine combustor application,with a ratio of hole pitch to row spacing P/S=1∶2,a porosity PS/d2=72,and an inclination angle α=30°.The current paper documented distribution of the overall cooling effectiveness on the wall surface,based on infrared imaging of the 2-D surface temperature *** results indicate:(1) The overall η increases along with the streamwise distance for the wide range of M due to the superposition effect of the multi-row film cooling.(2) The overall η substantially benefits from the multi-hole inside convective *** hole convective cooling not only complements the weakest film protection at initial rows but also helps mitigate the temperature gradient.(3) The overall η increases asymptotically with increasing M,unlike adiabatic η mostly published in the past,which decreased after M reached a specific *** current work showcased the end cooling outcome jointly driven by the filming cooling mechanism and the hole inside convective cooling mechanism.

关键词： gas turbine effusion cooling overall cooling effectiveness blowing ratio infrared imaging

Nonlinear Dimensionality Reduction by Local Orthogonality Preserving Alignment

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Journal of Computer Science & Technology 2016年第3期31卷 512-524页

作者： Tong lin Yao liu bo Wang Li-Wei Wang Hong-Bin Zha The Key Laboratory of Machine Perception (Ministry of Education) School of Electrical Engineering and Computer Sciences Peking University Beijing 100871 China

We present a new manifold learning algorithm called Local Orthogonality Preserving Alignment （LOPA）. Our algorithm is inspired by the Local Tangent Space Alignment （LTSA） method that aims to align multiple local neighborhoods into a global coordinate system using affine transformations. However, LTSA often fails to preserve original geometric quantities such as distances and angles. Although an iterative alignment procedure for preserving orthogonality was suggested by the authors of LTSA, neither the corresponding initialization nor the experiments were given. Procrustes Subspaces Alignment （PSA） implements the orthogonality preserving idea by estimating each rotation transformation separately with simulated annealing. However, the optimization in PSA is complicated and multiple separated local rotations may produce globally contradictive results. To address these difficulties, we first use the pseudo-inverse trick of LTSA to represent each local orthogonal transformation with the unified global coordinates. Second the orthogonality constraints are relaxed to be an instance of semi-definite programming （SDP）. Finally a two-step iterative procedure is employed to further reduce the errors in orthogonal constraints. Extensive experiments products, and neighborhoods of the original datasets. In that of PSA and comparable to that of state-of-the-art significantly faster than that of PSA, MVU and MVE. show that LOPA can faithfully preserve distances, angles, inner comparison, the embedding performance of LOPA is better than algorithms like MVU and MVE, while the runtime of LOPA is

关键词： manifold learning dimensionality reduction senti-definite programming Procrustes measure

Divergent Syntheses of Pyridoacridine Alkaloids via Palladium-Catalyzed Reductive Cyclization with Nitro-Biarenes

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Chinese Journal of Chemistry 2021年第7期39卷 1905-1910页

作者： bo liu Shuping Wang Changhao Bian Hongze Liao Hou-Wen lin Research Center for Marine Drugs State Key Laboratory of Oncogene and Related GenesDepartment of PharmacyRen Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200127 China

Main observation and conclusion A divergent and novel protocol for the preparation of both pyrido[2,3,4-kl]acridine and pyrido[4,3,2-kl]acridine alkaloids was *** method featured the remote palladium-catalyzed reductive cyclization with Mo(CO)_(6) as reductant.A wide range of substrates including three types of nitro arenes were tolerated and afforded corresponding products in good to excellent yields.

关键词： Polycyclic heteroaromatics Palladium-catalyzed reductive cyclization Marine nature alkaloids Divergent syntheses Pyridoacridine

Effect of nano-graphite on mechanical properties and oxidation resistance of ZrB_(2)-SiC-graphite electrode ceramics

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Journal of Iron and Steel Research International 2024年第6期31卷 1502-1513页

作者： bo-lin Yang Chang-liu Kuang Zheng-long liu Chao Yu Cheng-ji Deng Jun Ding The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrB_(2)-based ceramic composites were prepared by spark plasma sintering using ZrB_(2) powder prepared by molten salt method as raw material and SiC and nano-graphite as *** effects of nano-graphite addition on the physical properties and oxidation resistance of ZrB_(2)-based ceramic samples were *** results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of ZrB_(2)-based ceramic composites and improve the physical properties of the *** flexural strength of the ceramic sample with 8 vol.%nano-graphite reached 418.54 MPa,which was 53.14% higher than that of ZrB_(2)-SiC ceramic material(273.31 MPa),and its oxidation resistance was also significantly *** demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of ZrB_(2)-SiC ceramic *** prolonging its service life in application and promoting the development of ZrB_(2)-based ceramic composites,it is of great significance for clean steel smelting.

关键词： ZrB_(2)-SiC-graphite electrode ceramic ZrB_(2)-based ceramic composite Nano-graphite Physical property Oxidation resistance

Equivariant eta forms and equivariant differential K-theory

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Science China Mathematics 2021年第10期64卷 2159-2206页

作者： bo liu School of Mathematical Sciences Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China

In this paper,we propose a new numerical scheme for the coupled Stokes-Darcy model with the Beavers-Joseph-Saffman interface *** use the weak Galerkin method to discretize the Stokes equation and the mixed finite element method to discretize the Darcy equation.A discrete inf-sup condition is proved and the optimal error estimates are also *** experiments validate the theoretical analysis.

关键词： equivariant eta form equivariant differential K-theory equivariant spectral section equivariant higher spectral flow orbifold

Dynamics-based optimization of rolling schedule aiming at dual goals of chatter suppression and speed increase for a 5-stand cold tandem rolling mill

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Journal of Iron and Steel Research International 2021年第2期28卷 168-180页

作者： Zhi-ying Gao bo Tian Yang liu Li-yuan Zhang Mao-lin Liao School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the process of cold tandem rolling,chatter instability leads to serious impacts on enhancing rolling speed,improving product quality,reducing production cost and realizing *** occurs with the rolling speed up to a certain threshold value,but the critical speed is determined by both product specifications and rolling schedules.A 5-stand cold tandem rolling mill whose first three stands and subsequent two stands,respectively,have four and six rolls was investigated by formulating its dynamic equations with the corresponding structure-process *** applying the stability-based calculation model about the critical rolling speed in each stand,the system dynamic responses around the critical rolling speed were simulated,and the system eigenvalues which represent instability and characteristic frequencies were figured ***,via combining the critical rolling speeds with the system dynamic behavior,a dynamics-based optimization model of rolling schedule for the 5-stand cold tandem system was proposed for the purposes of both the chatter suppression and rolling speed *** the optimization model,eight rolling technique parameters(four strip thicknesses and four tensions between the upstream and downstream stands)were taken as design variables,and the constraint conditions were set as no chatter instability in all five stands,and the optimization goal was to maximize the outlet speed of the final *** pattern search method was introduced to solve the optimization *** applying such a dynamics-based optimization model for the 5-stand cold tandem rolling process,the chatter instability was suppressed effectively and the rolling efficiency was improved considerably;therefore,such an optimization model is expected to be valuable for intelligent manufacturing of rolling process.

关键词： Cold tandem rolling Chatter Critical rolling speed Rolling schedule Dynamics-based optimization Stability

Novel algorithm for detection and identification of radioactive materials in an urban environment

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Nuclear Science and Techniques 2023年第10期34卷 103-116页

作者： Hao-lin liu Hai-bo Ji Jiang-Mei Zhang Jing Lu Cao-lin Zhang Xing-Hua Feng Department of Automation University of Science and Technology of ChinaHefei 230026China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China Fundamental Science on Nuclear Wastes and Environment Safety Laboratory Southwest University of Science and TechnologyMianyang 621010China School of Automation and Information Engineering Sichuan University of Science and EngineeringZigong 643000China

This study introduces a novel algorithm to detect and identify radioactive materials in urban settings using time-series detector response data. To address the challenges posed by varying backgrounds and to enhance the quality and reliability of the energy spectrum data, we devised a temporal energy window. This partitioned the time-series detector response data, resulting in energy spectra that emphasize the vital information pertaining to radioactive materials. We then extracted characteristic features of these energy spectra, relying on the formation mechanism and measurement principles of the gammaray instrument spectrum. These features encompassed aggregated counts, peak-to-flat ratios, and peak-to-peak ratios. This methodology not only simplified the interpretation of the energy spectra's physical significance but also eliminated the necessity for peak searching and individual peak analyses. Given the requirements of imbalanced multi-classification, we created a detection and identification model using a weighted k-nearest neighbors(KNN) framework. This model recognized that energy spectra of identical radioactive materials exhibit minimal inter-class similarity. Consequently, it considerably boosted the classification accuracy of minority classes, enhancing the classifier's overall efficacy. We also executed a series of comparative experiments. Established methods for radionuclide identification classification, such as standard KNN, support vector machine, Bayesian network, and random tree, were used for comparison purposes. Our proposed algorithm realized an F1 measure of 0.9868 on the time-series detector response data, reflecting a minimum enhancement of 0.3% in comparison with other techniques. The results conclusively show that our algorithm outperforms others when applied to time-series detector response data in urban contexts.

关键词： Gamma-ray spectral analysis Nuclide identification Urban environment Temporal energy window Peakratio spectrum analysis Weighted KNN