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Journal of Iron and Steel Research International 2024年第8期31卷 2053-2067页

作者： Kang Zhou Wen-xiao Yu Bao-kai ren Gang wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Online estimation of the double nugget diameters was performed by means of a back propagation neural *** double nugget diameters were obtained using actual welding experiment and numerical simulation,according to different characteristics of aluminum nugget and steel *** input of the neural network was some key characteristic parameters extracted from dynamic power signal,which were peak point,knee point and their variation rate over time,as well as heat energy delivered into the welding *** architecture of the neural network was confirmed by confirming the number of neurons in hidden layer through a series of *** key parameters of the neural network were obtained by means of training 81 arrays of data ***,the neural network was used to test the remaining 20 arrays of verifying data set,and the results showed that both of the mean errors for the two nugget diameters were below 3%.In addition,corresponding analyses showed that the accuracy of two nugget diameters was higher than that of tensile-shear strength.

关键词： Resistance spot welding Aluminum Steel Double nugget Dynamic power signal.Neural network

Rapid Energy Exchange between In Situ Formed Bromine Vacancies and CO_(2)Molecules Enhances CO_(2)Photoreduction

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Research 2024年第2期2023卷 763-771页

作者： Qin ren Ye He Hong wang Yanjuan Sun Fan Dong Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China

Photocatalytic reduction of CO_(2)into fuels provides a prospective tactic for regulating the global carbon balance utilizing renewable solar ***,CO_(2)molecules are difficult to activate and reduce due to the thermodynamic stability and chemical *** this work,we develop a novel strategy to promote the adsorption and activation of CO_(2)molecules via the rapid energy exchange between the photoinduced Br vacancies and CO_(2)*** in situ continuous wave-electron paramagnetic resonance(cw-EPR)and pulsed EPR technologies,we observe that the spin-spin relaxation time(T_(2))of BiOBr is decreased by 198 ns during the CO_(2)photoreduction reaction,which is further confirmed by the broadened EPR *** result reveals that there is an energy exchange interaction between in situ formed Br vacancies and CO_(2)molecules,which promotes the formation of high-energy CO_(2)molecules to facilitate the subsequent reduction *** addition,theoretical calculations indicate that the bended CO_(2)adsorption configuration on the surface of BiOBr with Br vacancies caused the decrease of the lowest unoccupied molecular orbital of the CO_(2)molecule,which makes it easier for CO_(2)molecules to acquire electrons and get *** situ diffuse reflectance infrared Fourier transform spectroscopy further shows that the activated CO_(2)molecules are favorably converted to key intermediates of COOH*,resulting in a CO generation rate of 9.1μmol g^(-1)h^(-1)and a selectivity of 100%.This study elucidates the underlying mechanism of CO_(2)activation at active sites and deepens the understanding of CO_(2)photoreduction reaction.

关键词： reaction. adsorption activation

Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li ZHAO Yi ren Qi wang Lange DENG Feng ZHANG School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Neural networks Measurement uncertainty Position measurement Harmonic analysis Light emitting diodes Frequency estimation Indoor positioning systems

BioTreasury:a community-based repository enabling indexing and rating of bioinformatics tools

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Science China(Life Sciences) 2024年第2期67卷 221-229页

作者： Qi Zhao Xin Zhou Jingxing Wu Jieyi Cai Xiaoqiong Bao Lin Tang Chaoye wang Chunlei Liu Yukai wang Yuyan Teng Mohan Zheng Weiping Mu Zhixiang zuo Yubin Xie Xiaotong Luo Jian ren School of Life Sciences State Key Laboratory of Oncology in South ChinaCancer CenterGuangdong Provincial Clinical Research Center for CancerSun Yat-sen UniversityGuangzhou 510060China Institute of Precision Medicine The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Guangdong Institute of Gastroenterology Department of General SurgeryGuangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesThe Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510275China

The exponential growth of bioinformatics tools in recent years has posed challenges for scientists in selecting the most suitable one for their data analysis ***,to aid scientists in making informed choices,a community-based platform that indexes and rates bioinformatics tools is urgently *** this study,we introduce Bio Treasury(http://***),an integrated communitybased repository that provides an interactive platform for users and developers to share their experiences in various bioinformatics *** Treasury offers a comprehensive collection of well-indexed bioinformatics software,tools,and databases,totaling over 10,000 *** the past two years,we have continuously improved and maintained Bio Treasury,adding several exciting features,including creating structured homepages for every tool and user,a hierarchical category of bioinformatics tools and classifying tools using large language model(LLM).Bio Treasury streamlines the tool submission process with intelligent ***,Bio Treasury provides a wide range of social features,for example,enabling users to participate in interactive discussions,rate tools,build and share tool collections for the *** believe Bio Treasury can be a valuable resource and knowledge-sharing platform for the biomedical *** empowers researchers to effectively discover and evaluate bioinformatics tools,fostering collaboration and advancing bioinformatics research.

关键词： bioinformatics tools index tool database rating system large language model tool collections shari

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Improving mathematical model of burden distribution and correcting chute angle to cope with fluctuation of stock line

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Journal of Iron and Steel Research International 2024年第2期31卷 342-356页

作者： Jian-sheng Chen Wen-guo Liu Hao Guo wang Ding Qing-guo Xue Jing-song wang Hai-bin zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China MCC Capital Engineering&Research Incorporation Limited Beijing100176China Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina

Accurate evaluations of the burden distribution are of critical importance to stabilize the operation of blast *** mathematical model and discrete element method(DEM)are two attractive methods for predicting burden *** on DEM,the initial velocities of the pellet,sinter,and coke were calculated,and the velocity attenuations of the above three particles between the burden and the chute were *** initial velocity and velocity attenuation were applied to a mathematical model for improving the ***,based on the improved model,a scheme for rectifying the chute angles was proposed to address the fluctuation of the stock line and maintain a stable burden *** validity of the scheme was confirmed via a stable burden distribution under different stock *** mathematical model has been successfully applied to evaluate the online burden distribution and cope with the fluctuation of the stock line.

关键词： Burden distribution Mathematical model Discrete element method Velocity attenuation Stock line fluctuation

Highly sensitive fluorescent sensing and photocatalytic degradation performance of two-dimensional Tb-organic network

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Journal of Rare Earths 2024年第2期42卷 303-313,I0003页

作者： Ting Gao Zhihu Ma Yixia ren Zhixiang wang Meili Zhang Xiaoli Chen Jijiang wang Laboratory of New Energy and New Function Materials Shaanxi Key Laboratory of Chemical Reaction EngineeringCollege of Chemistry and Chemical EngineeringYan'an UniversityYan'an716000China

A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophthalic acid(H_(2)pyia) and 2,2'-bipyridine(2,2'-bipy) ligands,and characterized by single crystal X-ray diffraction,thermogravimetric(TG) analyses,powder X-ray diffraction(PXRD) and infrared(IR) technology.1 possesses a two-dimensional network based on the tetra-nuclear inorganic building units,and the π-πstacking interactions between the pyia^(2-) ligands and the guest 2,2'-bipy molecules play an important role in the forming of 3D supramolecular structure.1 exhibits excellent fluorescent sensing performance for Fe^(3+)(1.26×10^(-8) mol/L),Cr_(2)O_(7)^(2-)(8.1×10^(-7) mol/L),2,4,6-trinitrophenol(TNP)(2.71×10^(-8) mol/L)and tetracycline(TCT)(2.76×10^(-7) mol/L) in aqueous solution with lower detection *** sensing mechanisms of 1 were investigated by density functional theory(DFT) calculations,ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy,PXRD and fluorescent lifetime *** activated product of 1 was prepared by heating at 255℃ under constant pressure and used to photo-catalytically degrade *** 1 and the activated one have good photocatalytic degradation performance for TCT with degradation rates of 84.29% and 96.07%,*** photocatalytic mechanisms were discovered by UV-Vis diffuse reflectance spectroscopy and radical trap *** Tb-organic framework might be an excellent multifunctional fluorescent sensor and a good photocatalytic agent for TCT degradation in the future.

关键词： Tb-organic network Fluorescent sensing Photocatalytic degradation Rare earths

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Afforestation increases microbial diversity in low-carbon soils

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Journal of Forestry Research 2024年第2期35卷 14-22页

作者： Xuesen Pang Chuankuan wang Chengjie ren Zhenghu Zhou Center for Ecological Research Key Laboratory of Sustainable Forest Ecosystem Management‑Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin 150040People’s Republic of China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100People’s Republic of China

Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of plantings on soil microbial *** results showed that the overall effect of afforestation on soil microbial diversity was positive across the *** forest algorithm suggested that soil carbon was the most important factor regulating microbial diversity and the positive response was only found with new plantings on low-carbon bare lands but not on high-carbon farmlands and *** addition,afforestation with broadleaved species increased microbial diversity,whereas planting with conifers had no effect on microbial *** study clarified the effects of plantings on soil microbial diversity,which has an important implication for establishing appropriate policies and practices to improve the multiple functionalities(e.g.,biodiversity conservation and climate change mitigation)during plantation establishment.

关键词： Afforestation Microbial diversity Soil microbial communities Species-energy theory Plantations

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Research progress of MOF-based materials in the photocatalytic CO_(2)reduction

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Carbon Resources Conversion 2024年第1期7卷 103-121页

作者： Qian Su Qingjie Guo Haiquan wang Meifang Liu Cheng zuo College of Chemistry&Chemical and Environmental Engineering Weifang UniversityWeifangPeople’s Republic of China State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuanPeople’s Republic of China

Photocatalytic technology could utilize solar energy to reduce CO_(2)into high-value-added fossil fuels,providing promising solutions for global energy and environmental ***-organic frameworks(MOFs)are a class of crystalline porous solids with high porosity and flexible ***-based photocatalysts have excellent CO_(2)capture ability,photochemical and structural characteristics and have shown infinite development potential in CO_(2)***,in practical large-scale applications,MOF-based photocatalysts still have some urgent problems to be solved,such as high composite rate of photogenerated carriers,limited response range to visible spectrum,poor photocatalytic activity and weak reduction *** paper introduces series of MOF-based photocatalysts,including pure MOF materials,compounds,and derivatives,were reviewed based on recent *** was placed on the modification strategy of photocatalysts,the photocatalytic reaction’s key physical and chemical parameters,and the mechanism of synergistic improvement of chemical fuel *** and most importantly,the future development trends and prospects of MOF-based catalysts for photocatalytic CO_(2)reduction were discussed.

关键词： Photocatalysis Metal-organic frameworks Rational design CO_(2)reduction

In-situ UV-Vis Spectroscopy of Trisulfur Radicals in Lithium-Sulfur Batteries

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Chemical Research in Chinese Universities 2024年第2期40卷 279-286页

作者： DOU renju wang Qin ren Xiaoyan LU Lehui School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026P.R.China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P.R.China

Here we employ in-situ UV-Vis spectroscopy to monitor the sulfur redox reaction with oxygen-containing molecules as an additive,for example,biphenyl-4,4′-dicarboxylic acid(BDC).Furthermore,Raman spectrum,electron paramagnetic resonance(EPR),and electrospray ionization-mass spectrometry(ESI-MS)measurements reveal that the formation of BDC-S_(3)•^(‒)complexes can establish the long-term stability of polysulfide radicals,change the kinetics of sulfur redox reaction,and then generate decent capacity retention and rate *** to the density functional theory(DFT)analysis,S_(3)•^(‒)radicals are the underlying product of S_(6)^(2‒)cleavage,owing to the decreased chemical energy and the increased stability of S_(3)•^(‒)radicals through Lewis acid-base *** assembled Li-S batteries with BDC additive deliver a high reversible capacity of 420 mA·h·g^(−1)over 200 cycles with over 98%Coulombic efficiency,under the current density of 0.2 C.

关键词： Radical Polysulfide In-situ UV-Vis Spectroscopy Electrolyte additive Lithium-sulfur battery

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-Guo WU Guang-ren DUAN Yu wang Jie ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system