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Predicting of Covalent Organic Frameworks for Membrane-based Isobutene/1,3-Butadiene Separation:Combining Molecular Simulation and Machine Learning

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Chemical Research in Chinese Universities 2022年第2期38卷 421-427页

作者： CAO Xiaohao he Yanjing ZHANG Zhengqing SUN Yuxiu HAN Qi guo Yandong zhong Chongli State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387P.R.China School of Material Science and Engineering Tiangong UniversityTianjin 300387P.R.China School of Textile Science and Engineering Tiangong UniversityTianjin 300387P.R.China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387P.R.China College of Mathematics Science Bohai UniversityJinzhou 121013P.R.China

Efficient separation of C4 olefins is of critical importance and a challenging task in petrochemical industry. Covalent organic frameworks(COFs) could be used as promising candidates for membrane-based isobutene/1,3-butadiene(i-C4H8/C4H6) separation. Owing to large amounts of COFs appearing, however, the rapid prediction of optimal COFs is imperative before experimental efforts. In this work, we combine molecular simulation and machine learning to study COF membranes for efficient isolation of i-C4H8 over C4H6. Using molecular simulation, four potential COF membranes, which possess both high membrane performance score (MPS) value and moderate membrane selectivity were screened out and the mechanism of membrane separation further revealed is an adsorption dominated process. Further, random forest(RF) model with high prediction accuracy(R2>0.84) was obtained and used for elucidating key factors in controlling the membrane selectivity and i-C4H8 permeability. Ultimately, the optimal COF features were obtained through structure-performance relationship study. Our results may trigger experimental efforts to accelerate the design of novel COFs with better i-C4H8/C4H6separation performance.

关键词： Covalent organic framework Isobutene/1 3-butadiene separation Molecular simulation Machine learning

Pulsations of Three Rapidly Oscillating Ap Stars TIC 96315731,TIC72392575,and TIC 318007796

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Research in Astronomy and Astrophysics 2024年第8期24卷 157-168页

作者： Hai-Jian zhong Dong-Xiang Shen Chun-Hua Zhu he-Lei Liu Su-Fen guo guo-Liang Lü School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory National Astronomical ObservatoriesChinese Academy of SciencesUrumqi 830000China

We analyze the frequencies of three known roAp stars,TIC 96315731,TIC 72392575,and TIC 318007796,using the light curves from the Transiting Exoplanet Survey *** TIC 96315731,the rotational and pulsational frequencies are 0.1498360 day^(-1)and 165.2609 day^(-1),*** the case of TIC 72392575,the rotational frequency is 0.25551 day^(-1).We detect a quintuplet of pulsation frequencies with a center frequency of135.9233 day^(-1),along with two signals within the second pair of rotational sidelobes of the quintuplet separated by the rotation *** two signals may correspond to the frequencies of a dipole *** TIC318007796,the rotational and pulsational frequencies are 0.2475021 day^(-1),192.73995 day^(-1),and196.33065 day^(-1),*** on the oblique pulsator model,we calculate the rotation inclination(i)and magnetic obliquity angle(b)for the stars,which provide the geometry of the pulsation *** the phases of the frequency quintuplets,the pulsation amplitude and phase modulation curves,and the results of spherical harmonic decomposition,we conclude that the pulsation modes of frequency quintuplets in TIC96315731,TIC 72392575,and TIC 318007796 correspond to distorted dipole mode,distorted quadrupole mode,and distorted dipole mode,respectively.

关键词： asteroseismology-techniques photometric-stars oscillations(including pulsations)-stars chemically peculiar

Efficient Algorithms for Maximizing Group Influence in Social Networks

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Tsinghua Science and Technology 2022年第5期27卷 832-842页

作者： Peihuang Huang Longkun guo Yuting zhong College of Mathematics and Data Science Minjiang UniversityFuzhou 350108China College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350116China

In social network applications,individual opinion is often influenced by groups,and most decisions usually reflect the majority’s *** imposes the group influence maximization(GIM) problem that selects k initial nodes,where each node belongs to multiple groups for a given social network and each group has a weight,to maximize the weight of the eventually activated *** GIM problem is apparently NP-hard,given the NP-hardness of the influence maximization(IM) problem that does not consider *** on activating groups rather than individuals,this paper proposes the complementary maximum coverage(CMC) algorithm,which greedily and iteratively removes the node with the approximate least group influence until at most k nodes *** the evaluation of the current group influence against each node is only approximate,it nevertheless ensures the success of activating an approximate maximum number of ***,we also propose the improved reverse influence sampling(IRIS) algorithm through fine-tuning of the renowned reverse influence sampling algorithm for ***,we carry out experiments to evaluate CMC and IRIS,demonstrating that they both outperform the baseline algorithms respective of their average number of activated groups under the independent cascade(IC)model.

关键词： complementary maximum coverage(CMC) improved reverse influence sampling(IRIS) group influence maximization(GIM) independent cascade(IC)model

A parameter formula connecting PID and ADRC

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Science China(Information Sciences) 2020年第9期63卷 175-187页

作者： Sheng zhong Yi HUANG Lei guo Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper presents a parameter formula connecting the well-known proportional-integralderivative(PID) control and the active disturbance rejection control(ADRC). On the one hand, this formula gives a quantitative lower bound to the bandwidth of the extended state observer(ESO) used in ADRC,implying that the ESO is not necessarily of high gain. On the other hand, enlightened by the design of ADRC, a new PID tuning rule is provided, which can guarantee both strong robustness and nice tracking performance of the closed-loop systems under the PID control. Moreover, it is proved that the ESO can be rewritten as a suitable linear combination of the three terms in PID, which can give a better estimate for the system uncertainty than the single integral term in the PID controller. Theoretical results are verified also by simulations in the paper.

关键词： nonlinear uncertain systems proportional-integral-derivative PID active disturbance rejection control ADRC extended state observer ESO

BODIPY-derived ratiometric fluorescent sensors: pH-regulated aggregation-induced emission and imaging application in cellular acidification triggered by crystalline silica exposure

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Science China Chemistry 2018年第11期61卷 1413-1422页

作者： Yang Bai Danyang Liu zhong Han Yuncong Chen zhongyan Chen Yang Jiao Weijiang he Zijian guo State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute School of Chemistry and Chemical EngineeringNanjing University

Modification of classic fluorophore to possess the emission transitions between aggregation-induced emission （ALE） and intrinsic emission offers reliable approach to the design of ratiometric fluorescent sensors. In this study, a proton acceptor benzimidazole was integrated with BODIPY to form three compounds, BBI-1/2/3, which demonstrated the AIE （-595 nm, Iagg） in neutral aqueous medium and intrinsic BODIPY emission （-510 nm,Iint） in acidic medium. All the three showed the ratiometric pH sensing behavior in a dual excitation/dual emission mode, yet BBI-3 displayed still the dual emission ratiometric pH sensing ability. The pH-dependent emission ratio/int/Iagg of the three were fully reversible, and no interference was observed from normal abundant chemical species in live cells. Their different pKa （BBI-1, pKa 4.4; BBI-2, pKa 2.7; BBI-3, pKa 3.6） suggested that the substituents on benzimidazole moiety were essential to govern their functioning pH range. The ratiometric imaging of BBI-1 in A549 cells provided an effective intracellular pH （pHi） calibration formula corresponding to emission ratio oflJ Iint/Iagg. Ratiometric pH imaging in A549 cells upon small particle exposure confirmed the particle-induced cellular acidification with this formula. Both particle size and the chemical nature of the particle contribute to the observed acidification effect. The synchronization of lysosome disruption to cellular acidification in A549 cells upon crystalline silica exposure was directly observed for the first time with BBI-1, showing the potential application of BBI-1 in the study of silicosis and other related diseases. This study de- monstrated that endowing fluorophore with AIE/intrinsic emission transition could be a promising strategy for ratiometric sensor design.

关键词： fluorescence imaging sensor cellular acidification aggregation-induced emission crystalline silica lysosome BODIPY

High-Repetition-Rate and High-Beam-Quality Laser Pulses with 1.5 MW Peak Power Generation from a Two-Stage Nd:YVO4 Amplifier

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Chinese Physics Letters 2019年第11期36卷 22-26页

作者： Qiu-Run he Jing guo Bao-Fu Zhang zhong-Xing Jiao School of Physics Sun Yat-sen UniversityGuangzhou 510275 Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082 National Demonstration Center for Experimental Physics Education Sun Yat-sen UniversityGuangzhou 510275

We develop a two-stage end-pumped Nd:YVO4 amplifier seeded by a passively Q-switched microchip laser. An average output power of 13.5 W with repetition rate up to 7 kHz and pulse duration of ~1.24 ns is obtained,corresponding to a pump extraction efficiency of 16.1%(19.5% for the second stage) and peak power of ~1.5 *** beam quality factors at maximum output power are measured to be Mx2= 1.56 and My2= 1.48. We introduce an analytical model to estimate gain and beam quality after amplification. This model focuses on the influence of ratio of seed spot radius to pump spot radius when designing an amplifier. Moreover, our experiments reveal that the re-imaging system in the double-pass configuration can be used to enhance the beam quality.

关键词： Nd:YVO4 amplifier pump

Research and Application of Flat Roll Technology in the Downstream Stands for CSP

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Journal of Iron and Steel Research International 2011年第4期18卷 30-35页

作者： guo De-fu he An-rui SHAO Jian YANG Quan WANG zhong-ming WANG bo National Engineering Research Center of Advanced Rolling University of Science and Technology Beijing Beijing 100083 China Hot Strip Plant of Ma'anshan Iron and Steel Co Ltd Ma'anshan 243000 Anhui China

CVC mills are generally used in the whole stands of CSP（Compact Strip Product）.Their special ＂s＂ curve of work roll contour and shifting strategy aimed at controlling strip shape,and the characteristics of continuous casting and rolling production,which make the work roll wear in downstream stands seriously uneven,and easily form abnormal transverse profile at the rolling *** a result,CVC mill configuration in the downstream stands can not meet the profile and flatness control requirement for schedule free rolling,and bring some difficulties in profile and flatness control for the subsequent cold *** on the characteristics of the shape control system of CSP production line,and combined with the theory of flat roll technology,a kind of technology solution of using flat roll in the downsteam stands for CSP hot strip mills was *** last,industrial test was carried out in the last stand of Masteel CSP,and good results were obtained.

关键词： CSP flat roll wear shifting strategy profile flatness

In-situ pressure-preserved coring for deep exploration:Insight into the rotation behavior of the valve cover of a pressure controller

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Petroleum Science 2023年第4期20卷 2386-2398页

作者： Da guo he-Ping Xie Ling Chen zhong-Ya Zhou he-Ping Lu Lin Dai Ding-Ming Wang Tian-Yu Wang Ju Li Zhi-Qiang he Yun-Qi Hu Ming-zhong Gao School of Mechanical Engineering Sichuan UniversityChengduSichuan610065China MOE Key Laboratory of Deep Underground Science and Engineering College of Water Resource and HydropowerSichuan UniversityChengduSichuan610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhenGuangdong518060China Petroleum Engineering Technology Research Institute of Sinopec Jianghan Oilfield Company WuhanHubei430035China

In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas *** IPP-Coring,because the rotation behavior of the pressure controller valve cover in different medium environments is unclear,interference between the valve cover and inner pipe may occur and negatively affect the IPP-Coring success *** address this issue,we conducted a series of indoor experiments employing a high-speed camera to gain greater insights into the valve cover rotation behavior in different medium environments,e.g.,air,water,and simulated drilling *** results indicated that the variation in the valve cover rotation angle in the air and fluid environments can be described by a one-phase exponential decay function with a constant time parameter and by biphasic dose response function,*** rotation behavior in the fluid environments exhibited distinct elastic and gravitational acceleration *** the fluid environments,the density clearly impacted the valve cover closing time and rotation behavior,whereas the effect of viscosity was very *** can be attributed to the negligible influence of the fluid viscosity on the drag coefficient found in this study;meanwhile,the density can increase the buoyancy and the time period during which the valve cover experienced a high drag *** these results,control schemes for the valve cover rotation behavior during IPP-Coring were proposed for different layers and geological conditions in which the different drilling fluids should be used,e.g.,the use of a high-density valve cover in high-pore pressure layers.

关键词： In-situ coring Pressure coring Pressure controller Rotation behavior Drilling fluid

Wenchuan earthquake:Brightness temperature changes from satellite infrared information

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Chinese Science Bulletin 2010年第18期55卷 1917-1924页

作者： ZHANG YuanSheng guo Xiao zhong MeiJiao SheN WenRong LI Wen he Bin Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China Lanzhou Base of Institute of Earthquake Prediction China Earthquake Administration Lanzhou 730000 China

By using an alternative processing method for satellite infrared remote sensing data and adopting the China Geostationary Meteorological Satellite(FY-2C) infrared remote sensing brightness temperature data,we studied the great 2008 Wenchuan Ms8.0 *** indicate the obvious characteristic period and amplitude,and distribution of thermal infrared anomalies before the Wenchuan *** we discussed the mechanism of the observed pre-earthquake thermal *** characteristics of observed thermal infrared anomalies are easy to be recognized and applied,and could provide a criterion for thermal anomalies of earthquakes.

关键词：红外信息大地震温度变化卫星汶川亮度遥感数据地球同步