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Tsinghua Science and Technology 2005年第z1期10卷 797-802页

作者： ye qiang LI Yijun zhang Yiwen School of Management Harbin Institute of Technology Harbin 150001 China School of Management Harbin Institute of Technology Harbin 150001 China Department of Management Information Systems University of Arizona Tucson 85705 U.S.A.

Sentiment classification is an automatic opinion classification method to classify the product reviews on web into positive or negative opinions to help consumers or sellers to understand the opinions and evaluations from existing customers. Semantic-oriented approach is one of the recent developments in sentiment classification. Up to now, most research of sentiment classification is on English reviews,and little work has been done on Chinese reviews using sentiment classification. The detailed techniques used in English review cannot be applied directly to Chinese reviews due to the different characteristics between these two languages. This study modified and improved the semantic-oriented approach to a 6-step process for Chinese review, focusing on the modification and improvement on the text segmentation and reference words pairs (RWPs) identification. Two experiments were conducted on book reviews and cell phone reviews. The results show that the performances of the proposed approach are comparable to those of the existing English reviews classification studies.

关键词： sentiment classification Chinese customer reviews books cell phones semantic orientation

An MFC capable of regenerating the cathodic electron acceptor under sunlight

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中国科学：技术科学英文版 2010年第9期53卷 2489-2494页

作者： FU Qian,LI Jun,ZHU Xun,LIAO qiang,ye DingDing & zhang Liang Institute of Engineering Thermophysics,Chongqing University,Chongqing 400030,China Institute of Engineering Thermophysics Chongqing University

A renewable MFC (microbial fuel cell) cathode was used in this study because the iodide ion could react with oxygen to generate triiodide under natural *** feasibility of the regeneration of triiodide ion under natural sunlight and the effect of the regenerated triiodide ion concentration on the MFC performance were *** results showed that the power density of the MFC using triiodide ion as cathodic electron acceptor was significantly higher than that of using ferricyanate,and that the iodide ion can be oxidized to triiodide ion by oxygen in air at the expense of natural *** addition,it was obvious from the experimental results that the MFC performance was improved with the increase of the triiodide concentration,indicating that the concentration of triiodide ion had a critical effect on the MFC *** linear sweep voltammetry (LSV) curves for the electro-reduction of triiodide ion on the carbon paper were obtained and the results suggested that the diffusion process of triiodide ions to cathode was the control factor for the MFC performance.

关键词： microbial fuel cell cathodic electron acceptor triiodide ion

Recycling of spent lithium-ion batteries to resynthesize high-performance cathode materials for sodium-ion storage

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Tungsten 2024年第3期6卷 574-584页

作者： Hai-qiang Gong Xing-Yuan Wang Long ye Bao zhang Xing Ou National Engineering Laboratory for High-Efficiency Recovery of Refractory Nonferrous Metals School of Metallurgy and Environment Central South University

The spent lithium-ion batteries recovery has been brought into focus widely for its environmental imperatives and potential profits from the metal components,such as lithium,cobalt,nickel and ***,the weaker pollution and fewer profits of LiMn2O4cathode dispel the enthusiasm and responsibility of industry ***,a simplified and efncient method to regenerate the sodium-ion cathode materials and separate Li from spent LiMn2O4materials for the profit improvement is *** detail,adjusting the parameters of carbothermal reduction process appropriately,the LiMn2O4spinel structure is destroyed within a short period time and transformed into simple metal *** anticipated,nearly 95 wt.%lithium can be obtained and recovered during the water leaching,while 99 wt.% of manganese can be extracted in acid *** that the leaching residue can return to the carbothermic reduction,leading to a closed-loop economic recycling *** regenerated Na0.67Ni0.3Mn0.7O2cathode displays excellent electrochemical performance with superior cycling stability(the initial capacity reaches 95.9 mAh·g-1,and the retention rate reached 98.3% after 100 cycles at 1 C).The delicate strategy of sodium-ion cathode material regenerated from spent LiMn2O4aims to realize lithium separation and material utilization of manganese simultaneously,providing the instructive suggestion to rise up the recycling profits of spent batteries.

关键词： Manganese Spent battery LiMn 2 O 4 cathode Recycling Regenerated Na 0.67 Ni 0.3 Mn 0.7 O 2 Sodium-ion storage

Insight into the selective separation of CO_(2)from biomass pyrolysis gas over metal-incorporated nitrogen-doped carbon materials:a first-principles study

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 1-12页

作者： Li Zhao Xinru Liu Zihao ye Bin Hu Haoyu Wang Ji Liu Bing zhang qiang Lu National Engineering Research Center of New Energy Power Generation North China Electric Power UniversityBeijing102206China

The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further ***-incorporated nitrogen-doped materials exhibit enormous potential,whereas the relevant adsorption mechanism is still ***,16 metal-incorporated nitrogen-doped carbon materials were designed based on the density functional theory calculation,and the adsorption mechanism of pyrolysis gas components H2,CO,CO_(2),CH_(4),and C2H6 was *** results indicate that metal-incorporated nitrogen-doped carbon materials generally have better adsorption effects on CO and CO_(2)than on H_(2),CH_(4),and C_(2)H_(6).Transition metal Mo-and alkaline earth metal Mg-and Ca-incorporated nitrogen-doped carbon materials show the potential to separate CO and CO_(2).The mixed adsorption results of CO_(2)and CO further indicate that when the CO_(2)ratio is significantly higher than that of CO,the saturated adsorption of CO_(2)will precede that of ***,the three metal-incorporated nitrogen-doped carbon materials can selectively separate CO_(2),and the alkaline earth metal Mg-incorporated nitrogen-doped carbon material has the best *** study provides theoretical guidance for the design of carbon capture materials and lays the foundation for the efficient utilization of biomass pyrolysis gas.

关键词： CO_(2)capture biomass pyrolysis gas selective adsorption carbon materials first-principles

From Liquid to Solid‑State Lithium Metal Batteries:Fundamental Issues and Recent Developments

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Nano-Micro Letters 2024年第2期16卷 68-125页

作者： Zhao zhang Wei‑qiang Han School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China

The widespread adoption of lithium-ion batteries has been driven by the proliferation of portable electronic devices and electric vehicles,which have increasingly stringent energy density *** metal batteries(LMBs),with their ultralow reduction potential and high theoretical capacity,are widely regarded as the most promising technical pathway for achieving high energy density *** this review,we provide a comprehensive overview of fundamental issues related to high reactivity and migrated interfaces in ***,we propose improved strategies involving interface engineering,3D current collector design,electrolyte optimization,separator modification,application of alloyed anodes,and external field regulation to address these *** utilization of solid-state electrolytes can significantly enhance the safety of LMBs and represents the only viable approach for advancing *** review also encompasses the variation in fundamental issues and design strategies for the transition from liquid to solid *** noteworthy is that the introduction of SSEs will exacerbate differences in electrochemical and mechanical properties at the interface,leading to increased interface inhomogeneity—a critical factor contributing to failure in all-solidstate lithium metal *** on recent research works,this perspective highlights the current status of research on developing high-performance LMBs.

关键词： Lithium metal batteries All-solid-state lithium metal battery Li dendrite Solid electrolyte Interface

Transforming liquid flow fuel cells to controllable reactors for highlyefficient oxidation of 5-hydroxymethylfurfural to 2, 5-furandicarboxylic acid at low temperature

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Journal of Energy Chemistry 2024年第3期90卷 621-631,I0014页

作者： ye qiang Xi Liu Denghao Ouyang Zhao Jiang Xuebing Zhao Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied Chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina

Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still ***,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild *** LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to *** reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of *** a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism.

关键词： 5-Hydroxymethylfurfural 2 5-Furandicarboxylic acid Electrodeposition Electron transport chain Liquid flow fuel cell

PSRDP:A Parallel Processing Method for Pulsar Baseband Data

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Research in Astronomy and Astrophysics 2024年第1期24卷 300-310页

作者： Ya-Zhou zhang Hai-Long zhang Jie Wang Xin-Chen ye Shuang-qiang Wang Xu Du Han Wu Ting zhang Shao-Cong Guo Meng zhang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China Southeast University Nanjing 211189China School of Cyber Science and Engineering Qufu Normal UniversityQufu 273165China

To address the problem of real-time processing of ultra-wide bandwidth pulsar baseband data,we designed and implemented a pulsar baseband data processing algorithm(PSRDP)based on GPU parallel computing *** can perform operations such as baseband data unpacking,channel separation,coherent dedispersion,Stokes detection,phase and folding period prediction,and folding integration in GPU *** tested the algorithm using the J0437-4715 pulsar baseband data generated by the CASPSR and Medusa backends of the Parkes,and the J0332+5434 pulsar baseband data generated by the self-developed backend of the Nan Shan Radio *** obtained the pulse profiles of each baseband *** experimental analysis,we have found that the pulse profiles generated by the PSRDP algorithm in this paper are essentially consistent with the processing results of Digital Signal Processing Software for Pulsar Astronomy(DSPSR),which verified the effectiveness of the PSRDP ***,using the same baseband data,we compared the processing speed of PSRDP with DSPSR,and the results showed that PSRDP was not slower than DSPSR in terms of *** theoretical and technical experience gained from the PSRDP algorithm research in this article lays a technical foundation for the real-time processing of QTT(Qi Tai radio Telescope)ultra-wide bandwidth pulsar baseband data.

关键词： (stars:)pulsars:general methods:data analysis techniques:miscellaneous

Effect of dissolved-oxygen on the flotation behavior of pyrite at high altitude area

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2148-2158页

作者： Yan Miao Guangke ye Guofan zhang School of Minerals Processing and Bio-engineering Central South UniversityChangsha 410083China

With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been *** is a consensus that moderate oxidation of sulfide ore is beneficial to flotation,but the specific suitable dissolved oxygen value is inconclusive,and there are few studies on sulfide ore flotation under low dissolved oxygen environment at high *** this paper,we designed and assembled an atmosphere simulation flotation equipment to simulate the flotation of pyrite at high altitude by controlling the partial pressure of N_(2)/O_(2) and dissolved oxygen under atmospheric conditions.X-ray photoelectron spec-troscopy(XPS),atomic force microscope(AFM),Fourier transform infrared spectrometer(FT-IR),UV-vis spectrophotometer,zeta po-tential,and contact angle measurements were used to reveal the effects of surface oxidation and agent adsorption on pyrite at high altitude(4600 m dissolved oxygen(DO)=4.0 mg/L).The results of pure mineral flotation indicated that the high altitude and low dissolved oxy-gen environment is favorable for pyrite *** angle measurements and XPS analysis showed that the high altitude atmosphere nslows down the oxidation of pyrite surface,facilitates S_(n)^(2-)/S^(0) production and enhances surface *** calcula-tions and zeta potential analysis showed that the influence of atmosphere on the form of pyrite adsorption is small,and the different atmo-spheric conditions are consistent with dixanthogen electrochemical adsorption,with lower Zeta potential under high altitude atmosphere and significant potential shift after sodium isobutyl xanthate(SIBX)*** results of FT-IR,UV-vis,and AFM analysis showed that SIBX adsorbed more on the surface of pyrite under high altitude atmosphere and adsorbed on the surface in a mesh structure com-posed of column/*** results of the experimental study revealed the reasons for the easy flotation of sul

关键词： high altitude dissolved-oxygen pyrite flotation oxidation

An attention graph stacked autoencoder for anomaly detection of electro-mechanical actuator using spatio-temporal multivariate signals

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 506-520页

作者： Wang, Jianyu zhang, Heng Miao, qiang Sichuan Univ Coll Elect Engn Chengdu 610065 Peoples R China

Health monitoring of electro-mechanical actuator (EMA) is critical to ensure the security of airplanes. It is difficult or even impossible to collect enough labeled failure or degradation data from actual EMA. The autoencoder based on reconstruction loss is a popular model that can carry out anomaly detection with only consideration of normal training data, while it fails to capture spatio-temporal information from multivariate time series signals of multiple monitoring sensors. To mine the spatio-temporal information from multivariate time series signals, this paper proposes an attention graph stacked autoencoder for EMA anomaly detection. Firstly, attention graph convolution is introduced into autoencoder to convolve temporal information from neighbor features to current features based on different weight attentions. Secondly, stacked autoencoder is applied to mine spatial information from those new aggregated temporal features. Finally, based on the benchmark reconstruction loss of normal training data, different health thresholds calculated by several statistic indicators can carry out anomaly detection for new testing data. In comparison with traditional stacked autoencoder, the proposed model could obtain higher fault detection rate and lower false alarm rate in EMA anomaly detection experiment. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics.

关键词： Anomaly detection Spatio-temporal informa- tion Multivariate time series sig- nals Attention graph convolu- tion Stacked autoencoder FAULT-DIAGNOSIS

UWLPIPE:Ultra-wide Bandwidth Low-frequency Pulsar Data Processing Pipeline

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Research in Astronomy and Astrophysics 2024年第7期24卷 145-157页

作者： Ya-Zhou zhang Hai-Long zhang Jie Wang Jian Li Xin-Chen ye Shuang-qiang Wang Xu Du Han Wu Ting zhang Shao-Cong Guo Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China Southeast University Nanjing 211189China

For real-time processing of ultra-wide bandwidth low-frequency pulsar baseband data,we designed and implemented an ultra-wide bandwidth low-frequency pulsar data processing pipeline(UWLPIPE)based on the shared ringbuffer and GPU parallel *** runs on the GPU cluster and can simultaneously receive multiple 128 MHz dual-polarization VDIF data packets preprocessed by the front-end *** aligning the dual-polarization data,multiple 128M subband data are packaged into PSRDADA baseband data or multi-channel coherent dispersion filterbank data,and multiple subband filterbank data can be spliced into wideband data after time *** used the Nanshan 26 m radio telescope with the L-band receiver at964~1732 MHz to observe multiple ***,we processed the data using DSPSR software,and the results showed that each subband could correctly fold out the pulse profile,and the wideband pulse profile accumulated by multiple subbands could be correctly aligned.

关键词： (stars)pulsars general-methods data analysis-techniques miscellaneous