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Characterization and ultraviolet-visible shielding property of samarium-cerium compounds containing Sm_(2)O_(2)S prepared by co-precipitation method

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1809-1816页

作者： Yanping Li Xue Bian Xun Jin peng cen Wenyuan Wu Gaofeng Fu Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education Shenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

Since ultraviolet(UV)light,as well as blue light,which is part of visible light,is harmful to skin,samarium-cerium compounds containing Sm_(2)O_(2)S were synthesized by co-precipitation method.This kind of compounds blocks not only UV light,but also blue light.The minimum values of average transmittance(360-450 nm)and band gap of samarium-cerium compounds were 8.90%and 2.76 eV,respectively,which were less than 13.96%and 3.01 eV of CeO_(2).Elemental analysis(EA),X-ray diffraction(XRD),Fourier transformation infrared(FTIR),and Raman spectra determined that the samples contained Ce_(4)O_(7),Sm_(2)O_(2)S,Sm_(2)O_(3),and Sm_(2)O_(2)SO_(4).The microstructure of samples was analyzed by scanning and transmission electron microscopies(SEM and TEM).X-ray photoelectron spectrum(XPS)showed that cerium had Ce^(3+)and Ce^(4+) valence states,and oxygen was divided into lattice oxygen and oxygen vacancy,which was the direct cause of the decrease of average transmittance and band gap.

关键词： band gap co-precipitation method samarium-cerium compound ultraviolet light blue light

Only Sunda and Chinese pangolin(Pholidota)are naturally distributed in China

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Integrative Zoology 2023年第4期18卷 704-709页

作者： peng cen Jiankun SUN Qiaoyan WANG Fuhua ZHANG Lianxian MO Amna MAHMOOD Jiaqi LI Yifu WANG Shibao WU School of Life Science South China Normal UniversityGuangzhouChina Administration of Xishuangbanna National Nature Reserve XishuangbannaChina Administration of Gaoligongshan National Nature Reserve in Baoshan BaoshanChina Nanjing Institute of Environmental Science Ministry of Environmental ProtectionNanjingChina The University of Hong Kong HongkongChina IUCN SSC Pangolin Specialist Group LondonUK

INTRODUCTION Pangolin is the common name for animals in the Family Pholidota,Mammalia,which consists of eight extant species.All pangolin species have been listed as critically endangered(CR),endangered(EN),or vulnerable(VU)species in the International Union for Conservation of Nature(IUCN)Red List of Threatened Species(Challender et al.2020).In June 2020,the Chinese government upgraded the Chinese pangolin(Manis pentadactyla Linnaeus,1758)from a national second-class protected animal to a national first-class protected animal.In February 2021,the Sunda pangolin(Manis javanica Desmarest,1822)and the Indian pangolin(Manis crassicaudata Geoffroy,1803)were added to the list of national first-class protected animals.However,the number of species of pangolins naturally distributed in China varies in the literature:Some sources have recorded only one species,namely the Chinese pangolin(Nowak&Paradiso 1983;Sheng 1999),while most have recorded two species,namely the Chinese pangolin and Indian pangolin(Allen 1938;Zhang 1997;Wang 2003;Wu et al.2005a;Hu&Hu 2017).

关键词： protected Indian listed

Isoconversional kinetic analysis of decomposition of bastnaesite concentrates with calcium hydroxide

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Journal of Rare Earths 2020年第12期38卷 1361-1371页

作者： peng cen Xue Bian Wenyuan Wu School of Metallurgy Northeastern UniversityShenyang 110819China

Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energy was calculated,and the results indicate that the overall reaction involves more than one single step.The reaction with a lower content(15 wt%)involves another step which denotes the decomposition of newly formed calcium carbonate during roasting.The activation energy increases with increasing amount of calcium hydroxide in the lower range(0-15 wt%).This is due to the resistance of calcium hydroxide to heat and mass transport,However,more calcium can promote the decomposition reaction more effectively and thus reduce the activation energy.Nonlinear fitting was performed by fitting the experimental data to Avrami-Erofeev model to determine the reaction model and pre-exponential factor.The theoretical models were proven to be reliable for kinetic prediction.

关键词： Bastnaesite Thermal analysis kinetics Isoconversional method Calcium hydroxide Rare earths

华龙一号国际审查认证中结构完整性领域的实践和思考

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核动力工程 2024年第2期45卷 1-9页

作者：毛庆张涛徐晓岑鹏王国锋核电安全技术与装备全国重点实验室广东深圳518172 深圳中广核工程设计有限公司广东深圳518172 中广核工程有限公司广东深圳518172

为促进国际市场开发,中国广核集团有限公司开展了华龙一号核电技术方案英国通用设计审查(GDA)和欧洲用户要求认证(EUR)。核电厂构筑物、系统和设备的结构完整性是国际审查和认证的重点,为适应英国核安全监管和欧洲用户要求,项目团队采... 详细信息

为促进国际市场开发,中国广核集团有限公司开展了华龙一号核电技术方案英国通用设计审查(GDA)和欧洲用户要求认证(EUR)。核电厂构筑物、系统和设备的结构完整性是国际审查和认证的重点,为适应英国核安全监管和欧洲用户要求,项目团队采用分析法设计理念,以力学分析、试验和论证为关键手段,完成了英国版和欧洲版华龙一号的结构完整性分析评估和设计改进,全面满足了英国核安全监管和欧洲用户要求。通过华龙一号国际审查和认证,研究了结构完整性领域的相关技术要求,总结了审查过程中的实践和思考,可为华龙一号核电技术方案的持续改进和创新提供借鉴。

关键词：华龙一号(HPR1000) 英国通用设计审查(GDA) 欧洲用户要求认证(EUR) 结构完整性(SI)

Electrochemical properties of LiNi_(0.5)Mn_(1.3)Ti_(0.2)O_4/Li_4Ti_5O_(12)cells

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 457-460页

作者： Guo-qiang Liu Xi Wang Ya-jie Gao Lei Wen Guang-yin Liu Jian-jie Zheng peng cen Ying Li School of Materials and Metallurgy Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Spinel compounds LiNi0.5Mn1.3Ti0.2O4（LNMTO） and Li4Ti5O12 （LTO） were synthesized by different methods. The particle sizes of LNMTO and LTO are 0.5-2 and 0.5-0.8 μm, respectively. The LNMTO/LTO cell exhibits better electrochemical properties at both a low current rate of 0.2C and a high current rate of 1C. When the specific capacity was determined based on the mass of the LNMTO cathode, the LNMTO/LTO cell delivered 137 mA.h.g-1 at 0.2C and 118.2 mA-h-g-l at 1C, and the corresponding capacity retentions after 30 cycles are 88.5% and 92.4%, respectively.

关键词： lithium batteries titanium compounds nickel compounds manganese compounds oxides electrochemical properties

Sentiment Analysis Using Deep Learning Approach

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Journal on Artificial Intelligence 2020年第1期2卷 17-27页

作者： peng cen Kexin Zhang Desheng Zheng School of Computer Science Research Center for Cyber SecuritySouthwest Petroleum UniversityChengdu610500China

Deep learning has made a great breakthrough in the field of speech and image recognition.Mature deep learning neural network has completely changed the field of natural language processing(NLP).Due to the enormous amount of data and opinions being produced,shared and transferred everyday across the Internet and other media,sentiment analysis has become one of the most active research fields in natural language processing.This paper introduces three deep learning networks applied in IMDB movie reviews sentiment analysis.Dataset was divided to 50%positive reviews and 50%negative reviews.Recurrent Neural Network(RNN)and Long Short-Term Memory(LSTM)neural networks are two main types,which are widely used in NLP tasks,while Convolutional Neural Networks(CNN)is often used in image recognition.The results have shown that,CNN network model can achieve good classification effect when applied to sentiment analysis of movie reviews.CNN have reported the accuracy of 88.22%,while RNN and LSTM have reported accuracy of 68.64%and 85.32%respectively.

关键词： Deep learning RNN LSTM CNN sentiment analysis

Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector

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Computers, Materials & Continua 2024年第1期78卷 1503-1523页

作者： Cheng Zhao Zhe peng Xuefeng Lan Yuefeng cen Zuxin Wang School of Economics Zhejiang University of TechnologyHangzhouChina College of Management Zhejiang University of TechnologyHangzhouChina Informatization Office Zhejiang University of TechnologyHangzhouChina School of Information and Electronic Engineering Zhejiang University of Science&TechnologyHangzhouChina School of Economics and Management Universiti Putra MalaysiaDaerah PetalingNegeri SelangorMalaysia

The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits.

关键词： Public opinion sentiment structured multi-head attention stock index prediction deep learning

Performance and mechanism of CO_(2) absorption during the simultaneous removal of SO_(2) and NO_(x) by wet scrubbing process

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Journal of Environmental Sciences 2024年第1期135卷 534-545页

作者： peng Lu Xianhui Yan Lyumeng Ye Dingsheng Chen Dongyao Chen Jianhang Huang Chaoping cen Guangdong Province Engineering Laboratory for Air Pollution Control South China Institute of Environmental SciencesMinistry of Ecology and EnvironmentGuangzhou 510655China Guangdong Provincial Key Laboratory of Water and Air Pollution Control Guangzhou 510655China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

The co-removal of CO_(2)while removing SO_(2)and NOxfrom industrial flue gas has great potential of carbon emission reduction but related research is lacking.In this study,a wet scrubbing process with various urea solutions for desulfurization and denitrification was explored for the possibility of CO_(2)absorption.The results showed that the urea-additive solutions were efficient for NOxand SO_(2)abatement,but delivered<10%CO_(2)absorption efficiency.The addition of Ca(OH)_(2)dramatically enhanced the CO_(2)absorption,remained the desulfurization efficiency,unfortunately restricted the denitrification efficiency.Among various operating parameters,pH of solution played a determining role during the absorption.The contradictory pH demands of CO_(2)absorption and denitrification were observed and discussed in detail.A higher pH of solution than 10 was favorable for CO_(2)absorption,while the oxidizing of NO to NO_(2),NO_(2)^(-)or NO_(3)^(-)by NaClO_(2)was inhibited in this condition.When7

关键词： CO_(2)absorption Synergistic desulfurization and denitrification Wet scrubbing process Urea-NaClO_(2)-Ca(OH)_(2)absorbent Carbonation reaction

In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites

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Green Energy & Environment 2024年第1期9卷 126-137页

作者： peng Zhang Fukuan Li Mingming He Silu Huo Xueli Zhang Benqiang cen Dezhi Fang Kexun Li Hao Wang College of Environmental Science and Engineering Nankai UniversityTianjin300350China MOE Key Laboratory of Pollution Processes and Environmental Criteria Tianjin Key Laboratory of Environmental Remediation and Pollution ControlTianjin Key Laboratory of Environmental Technology for Complex Trans-Media PollutionNankai UniversityTianjin300350China State Key Laboratory of Simulation and Regulation of Water Cycles in River Basins China Institute of Water Resources and Hydropower ResearchBeijing100038China

Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricﬁeld and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption.

关键词： Electro-assisted adsorption Electrosorption Phosphate removal Active centers MOF-derived carbon