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Research in Astronomy and Astrophysics 2020年第12期20卷 270-278页

作者： fei-long he Qian Xu Na Wang Chun-Hua Zhu School of Physics and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

The influence of wind on the pointing accuracy of large aperture radio telescopes is becoming increasingly serious, especially at high observing frequency. Obtaining the wind field characteristics efficiently is very important to reduce the wind disturbance on antenna structure. In this paper, an error evaluation of numerical simulation method is established based on the measured data of single point wind tower, and the wind field characteristics are obtained from the evaluated numerical simulation results combined with the measured data for the 110 m aperture Qi Tai radio Telescope(QTT) site. According to the simulation results, compared with the measured data, the root mean square error(RMSE) of wind speed is less than 1 m s^-1, and the minimum wind speed RMSE is 0.2 m s^-1. An analysis of the wind field characteristics of the QTT site suggests that the active wind resistance design of the antenna periphery should focus on the SSW(south-south-west) direction.

关键词： telescopes site testing methods:data analysis

Defining two subpopulations of marginal zone B cells

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Cellular & Molecular Immunology 2024年第4期21卷 412-413页

作者： Xiaojing Liu fei-long Meng Key Laboratory of RNA Science and Engineering Shanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai200031China

Marginal zone(MZ)B cells,which are composed of heterogeneous subpopulations,are participate in the rapid response to *** et *** that MZ B cells can be divided into two distinct subpopulations based on CD80 *** two sub... 详细信息

关键词： expression. subpopulations al.

Electrolyte effect on electrochemical behaviors of manganese fluoride material for aqueous asymmetric and symmetric supercapacitors

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Rare Metals 2024年第3期43卷 1048-1061页

作者： Zheng-Hua he Jian-fei Gao Ling-Bin Kong State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou730050China

Exploring wide voltage window materials is not only an available measure to enhance the energy density of hybrid supercapacitor(HSCs),but also avoids the dynamic mismatch caused by different energy storage mechanisms of two electrodes in assembled symmetrical ***,there are few reports about the wide potential window materials except Bi_(2)O_(3)and VO_(2).Therefore,the MnF_(2)synthesized by solvothermal reaction was served as the electrode for *** MnF_(2)exhibited electrochemical activity in alkaline solution in three-electrode system,especially with a wide potential window from-0.8 to+0.5 V in 2 mol·L^(-1)***,the assembled MnF_(2)//MnF_(2)symmetrical HSC had a potential window of 1.5 V,and it exhibited outstanding long-cycle ***,when MnF_(2)was taken as the negative and positive respectively,the potential windows of asymmetric devices CoMoO_(4)//MnF_(2)and MnF_(2)//Activated Carbon(AC)could reach 1.3 and 1.45 V,respectively,showing excellent cycle *** work shows that MnF_(2)material has great research value in HSC,and provides a new research direction for developing high-performance devices.

关键词： Manganese fluoride Potential window Hybrid supercapacitors Electrochemical performance

Asymmetric Drying and Wetting Trends in Eastern and Western China

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Advances in Atmospheric Sciences 2024年第2期41卷 221-232页

作者： Wen WU fei JI Shujuan HU Yongli he College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China

As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous research has mainly focused on the long-term linear changes of dry/wet conditions, while the detection and evolution of the non-linear trends related to dry/wet changes have received less attention. The non-linear trends of the annual aridity index, obtained by the Ensemble Empirical Mode Decomposition(EEMD) method, reveal that changes in dry/wet conditions in China are asymmetric and can be characterized by contrasting features in both time and space in China. Spatially, most areas in western China have experienced transitions from drying to wetting, while opposite changes have occurred in most areas of eastern China. Temporally, the transitions occurred earlier in western China compared to eastern China. Research into the asymmetric spatial characteristics of dry/wet conditions compensates for the inadequacies of previous studies, which focused solely on temporal evolution;at the same time, it remedies the inadequacies of traditional research on linear trends over centennial timescales. Analyzing the non-linear trend also provides for a more comprehensive understanding of the drying/wetting changes in China.

关键词： aridity index EEMD dry/wet conditions asymmetric evolution

Sustainable Mining in the Era of Artificial Intelligence

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 1-4页

作者： long Chen Yuting Xie Yutong Wang Shirong Ge fei-Yue Wang IEEE the State Key Laboratory for Management and Control of Complex Systems at the Institute of Automation Chinese Academy of SciencesBeijing 100190China the National Laboratory of Pattern Recognition at the Institute of Automation and Waytous Ltd.China the School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275GuangdongChina the School of Mechanical Electronic and Information Engineering China University of Mining and Technology BeijingBejing 100083China the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100190China

The mining sector historically drove the global economy but at the expense of severe environmental and health repercussions,posing sustainability challenges[1]-[3].Recent advancements on artificial intelligence(AI)are revolutionizing mining through robotic and data-driven innovations[4]-[7].While AI offers mining industry advantages,it is crucial to acknowledge the potential risks associated with its widespread ***-reliance on AI may lead to a loss of human control over mining operations in the future,resulting in unpredictable consequences.

关键词： Sustainable mining consequences

Disposal of zinc extraction residues via iron ore sintering process:an innovative resource utilization

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Journal of Iron and Steel Research International 2024年第7期31卷 1636-1645页

作者： Chun-long Fan Cheng-yi Ding Tao Yang Yun-fei Luo Yi-fan Wang Qian Li Hong-ming long School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina Key Laboratory of Metallurgical Emission Reduction and Resources Recycling(Ministry of Education) Anhui University of TechnologyMa'anshan 243002AnhuiChina

Zinc extraction residue,a solid waste generated from the treatment of zinc-containing dust in rotary kilns,is commonly stockpiled in steel companies for extended *** poses significant disposal challenges and environmental pollution *** far,research on the treatment of zinc extraction residues has been slow,inadequate,and *** this gap,a novel approach was proposed to effectively treat the zinc extraction residue via the iron ore sintering *** was feasible to add 1 wt.%of zinc extraction residues to the sintering raw *** more adequate mineralization reaction resulted in higher yield and tumbler indexes,despite a slight decrease in sintering *** this may result in a slight decrease in sintering speed,the more complete mineralization reaction leads to improved sintering yield and tumbler ***,the addition of zinc extraction residues reduced the CO and NO_(x) concentrations in the sintering flue ***,the iron ore sintering process provided a viable solution for resource utilization and environmentally friendly treatment of zinc extraction residues.

关键词： Zinc extraction residue Iron ore sintering Co-processing Waste utilization Gas pollutant reduction

Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-fei Guo Ze-long Liang Yue-E Jiao Hang Xu Bin Zhao Key Laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

Phase behavior of gas condensate in porous media using real-time computed tomography scanning

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Petroleum Science 2024年第2期21卷 1032-1043页

作者： Wen-long Jing Lei Zhang Ai-Fen Li Jun-Jie Zhong Hai Sun Yong-fei Yang Yu-long Cheng Jun Yao Institute of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina

The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir *** was used as a sample to investigate the influence of porous media on the phase behavior of the gas *** pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network *** sandstone core sample was then saturated with gas condensate for the pressure depletion *** each pressure-depletion state was stable,realtime CT scanning was performed on the *** scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous *** network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas *** types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and *** results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT *** average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below *** volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet *** study provides crucial experimental evidence for the phase behavior chan

关键词： Gas condensate Pressure depletion Real-time micro-computed tomography scanning Distribution of condensate liquid

Enhanced performance of AlGaN-based ultraviolet light-emitting diodes with linearly graded AlGaN inserting layer in electron blocking layer

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Chinese Physics B 2019年第5期28卷 361-365页

作者： Guang Li Lin-Yuan Wang Wei-Dong Song Jian Jiang Xing-Jun Luo Jia-Qi Guo long-fei he Kang Zhang Qi-Bao Wu Shu-Ti Li Guangdong Engineering Research Center of Optoelectronic Functional Materials and Devices Institute of Opto-Electronic Materials and Technology South China Normal University Guangdong Institute of Semiconductor Industrial Technology Guangdong Academy of Sciences School of Intelligent Manufacture and Equipment Shenzhen Institute of Information Technology

The conventional stationary Al content Al GaN electron blocking layer(EBL) in ultraviolet light-emitting diode(UV LED) is optimized by employing a linearly graded Al Ga N inserting layer which is 2.0 nm Al_(0.3) Ga_(0.7) N/5.0 nm Alx Ga_(1-x) N/8.0 nm Al_(0.3) Ga_(0.7) N with decreasing value of x. The results indicate that the internal quantum efficiency is significantly improved and the efficiency droop is mitigated by using the proposed structure. These improvements are attributed to the increase of the effective barrier height for electrons and the reduction of the effective barrier height for holes,which result in an increased hole injection efficiency and a decreased electron leakage into the p-type region. In addition,the linearly graded AlGaN inserting layer can generate more holes in EBL due to the polarization-induced hole doping and a tunneling effect probably occurs to enhance the hole transportation to the active regions, which will be beneficial to the radiative recombination.

关键词： ultraviolet light-emitting diode electron blocking layer internal quantum efficiency

DISCRIMINANT INDEPENDENT COMPONENT ANALYSIS AS A SUBSPACE REPRESENTATION

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Journal of Electronics(China) 2006年第1期23卷 103-106页

作者： long fei he Jinsong Ye Xueyi Zhuang Zhenquan Li Bin Dept of Electronic Science and Technology USTC Hefei 230026 China

Subspace modeling plays an important role in face recognition. Independent Component Analysis （ICA）, a multivariable statistical analysis technique, can be seen as an extension of traditional Principal Com- ponent Analysis （PCA） technique, which addresses high order statistics as well as second order statistics. In this paper, a new scheme of subspace-based representation called Discriminant Independent Component Analysis （DICA） is proposed, which combines the strength＂ of unsupervised learning of ICA and supcrvised learning of Linear Discriminant Analysis （LDA）, and efficiently enhances the generalization ability of ICA-based representation method. Based on DICA subspace analysis, a set of optimal vectors called ＂discriminant independent faces＂ are learned from face samples. The effectiveness of our method is demonstrated by performance comparisons with some popular methods such as ICA, PCA, and PCA＋LDA. On the large scale database of IIS, significant improvements are observed when there are fewer training samples per person available.

关键词： Face recognition Subspace analysis Feature extraction Discriminant Independent Component Analysis (DICA).