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Polarization distribution in the image of a synchrotron emitting ring around a regular black hole

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Science China(Physics,Mechanics & Astronomy) 2022年第12期65卷 97-108页

作者： Xueyao liu Songbai Chen Jiliang jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationSynergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou225009China

The polarized images of a synchrotron emitting ring are studied in the regular Hayward and Bardeen black hole *** regular black holes carry a magnetic field in terms of gravity coupled to nonlinear *** show that the main features of the polarization images of the emitting rings are similar in these two regular black hole *** the magnetic charge parameter increases,the polarization intensity and the electric vector position angle in the image plane increase in Hayward and Bardeen black hole ***,the polarization intensity and electric vector position angle in the image of the emitting ring in the Hayward black hole spacetime are closer to those in the Schwarzschild *** effects of the magnetic charge parameter on the Strokes Q-U loops are also slightly smaller in the Hayward black hole *** information stored in the polarization images around Hayward and Bardeen black holes could help understand regular black holes and the gravity coupled to nonlinear electrodynamics.

关键词： black hole image regular black hole polarization distribution synchrotron emitting ring

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Imaging protein crystal growth behaviour in batch cooling crystallisation

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Chinese Journal of Chemical Engineering 2016年第1期24卷 101-108页

作者： jing J.liu Cai y.Ma Xue Z.Wang School of Chemistry and Chemical Engineering South China University of Technology Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds

The temporal and spatial growth behaviour of protein crystals, subject to different cooling strategies in protein crystallisation was investigated. Although the impact of temperature and cooling rate on crystal growth of small molecules was well documented, much less has been reported on their impact on the crystallisation of proteins. In this paper, an experimental set-up is configured to carry out such a study which involves an automatic temperature controlled hot-stage crystalliser fitted with a real-time imaging system. Linbro parallel crystallisation experiments(24-well plate) were also conducted to find the suitable initial conditions to be used in the hot-stage crystallisation experiments, including the initial concentration of HEW lysozyme solutions, precipitate concentration and pH value. It was observed that fast cooling rates at the early stage led to precipitates while slow cooling rates produced crystal nuclei, and very slow cooling rates, much smaller than for small molecules are critical to the growth of the nuclei and the crystals to a desired shape. The interesting results provide valuable insight as well as experimental proof of the feasibility and effectiveness of cooling as a means for achieving controlled protein crystallisation, compared with the evaporation approach which was widely used to grow single large crystals for X-ray diffraction study. Since cooling rate control can be easily achieved and has good repeatability, it suggests that large-scale production of protein crystals can be effectively achieved by manipulating cooling rates.

关键词： Hot-stage reactor On-line imaging of crystal growth Hen-Egg-White lysozyme cooling crystallisation Protein crystallisation Real-time in-process imaging

基于CCC认证标准的移动电源设计与合规性分析

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质量与认证 2025年第1期 60-63页

作者：刘其方欢陈静深圳市计量质量检测研究院

移动电源因其可实现对便携式电子设备(如手机、平板电脑等)的应急充电而深受消费者喜爱。然而,制造商为了应对激烈的市场竞争而过度追求性能与功能,由此可能带来安全隐患及环保挑战。本文结合GB 4943.1-2022和GB 31241-2022两项国家标准... 详细信息

移动电源因其可实现对便携式电子设备(如手机、平板电脑等)的应急充电而深受消费者喜爱。然而,制造商为了应对激烈的市场竞争而过度追求性能与功能,由此可能带来安全隐患及环保挑战。本文结合GB 4943.1-2022和GB 31241-2022两项国家标准,分析移动电源在CCC认证中常见的不合格项目,如:热灼伤、防火、无线功率发射器异物测试和电池安全等,并为企业的产品设计提供有针对性的指导建议,旨在提升其产品安全性和市场竞争力。

关键词：移动电源 CCC认证标准不合格项目安全

Preparation and properties of chitosan–metal complex：Some factors influencing the adsorption capacity for dyes in aqueous solution

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Journal of Environmental Sciences 2018年第4期30卷 301-309页

作者： Sadia Rashid Chensi Shen jing yang Jianshe liu jing Li College of Environmental Science and Engineering Donghua University Shanghai 201620 China State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry Shanghai 201620 China Beijing Enterprises Water Group (China) Investment Limited Beijing 100102 China

Chitosan–metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan–metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan–Fe（ Ⅲ） complex prepared by sulfate salts exhibited the best adsorption efficiency（100%） for various dyes in very short time duration（10 min）, and its maximum adsorption capacity achieved 349.22 mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan–metal complex. SO4^（2-） ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis ***, the p H sensitivity and the sensitivity of ionic environment for chitosan–metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan–metal complex can help not only in optimizing its use but also in designing new chitosan–metal based complexes.

关键词： Chitosan–metal complex Dye removal Coordination anion Adsorption optimization Crosslinking

Prescribed Performance Finite-Time Tracking Control for Uncertain Nonlinear Systems

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Journal of Systems Science & Complexity 2019年第3期32卷 803-817页

作者： jing yuanwei liu yang ZHOU Shaowei College of Information Science and Engineering Northeastern University Shenyang 110819 China College of Mathematics and Systems Science Shandong University of Science and Technology Qingdao 266590 China

This work investigates the finite-time tracking control problem for a class of uncertain strict-feedback nonlinear systems from a new perspective. First, a novel concept called finite-time performance function (FTPF) is defined. Further, a new sufficien t condition of finite-time st ability is derived and the tracking error can converge to a predefined region within a finite-time interval. The design process of the proposed technique is simpler. Finally, four simulation examples are carried out to illustrate the effectiveness of presented method.

关键词： Finite-time boundedness prescribed performance control uncertain nonlinear systems

Application and Characteristic Analysis of the Moist Singular Vector in GRAPES-GEPS

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Advances in Atmospheric Sciences 2020年第11期37卷 1164-1178页

作者： jing WANG Bin WANG Juanjuan liu yongzhu liu jing CHEN Zhenhua HUO State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China National Meteorological Center Beijing 100081China

The singular vector(SV)initial perturbation method can capture the fastest-growing initial perturbation in a tangent linear model(TLM).Based on the global tangent linear and adjoint model of GRAPES-GEPS(Global/Regional Assimilation and Prediction System-Global Ensemble Prediction System),some experiments were carried out to analyze the structure of the moist SVs from the perspectives of the energy norm,energy spectrum,and vertical *** conclusions are as follows:The evolution of the SVs is synchronous with that of the atmospheric circulation,which is *** moist and dry SVs are located in unstable regions at mid-to-high latitudes,but the moist SVs are wider,can contain more small-and medium-scale information,and have more energy than the dry *** the energy spectrum analysis,the energy growth caused by the moist SVs is reflected in the relatively small-scale weather *** addition,moist SVs can generate perturbations associated with large-scale condensation and precipitation,which is not true for dry *** the ensemble forecasts,the average anomaly correlation coefficient of large-scale circulation is better for the forecast based on moist SVs in the Northern Hemisphere,and the low-level variables forecasted by the moist SVs are also improved,especially in the first 72 *** addition,the moist SVs respond better to short-term precipitation according to statistical precipitation scores based on 10 *** inclusion of the large-scale condensation process in the calculation of SVs can improve the short-term weather prediction effectively.

关键词： moist singular vector GRAPES-GEPS adjoint model ensemble prediction

Integration of resonant band with asymmetry in ferroelectric tunnel junctions

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npj Computational Materials 2022年第1期8卷 518-524页

作者： jing Su jing Li Xingwen Zheng Shijie Xie Xiaohui liu School of Physics Shandong University250100Ji’nanChina

We propose that the asymmetry-induced tunneling electroresistance(TER)effect in a ferroelectric tunnel junction(FTJ)could be improved by integrating a polarization-controlled resonant *** first-principles calculations and a quantum-mechanical tunneling model,we studied an asymmetric FTJ SrRuO_(3)/BaTiO_(3)/SrTiO_(3)/SrRuO_(3).The resonant band is integrated into this FTJ by two atomic layers of BaSnO_(3)embedded in the *** the elaborated FTJ SrRuO_(3)/BaTiO_(3)/BaSnO_(3)/SrTiO_(3)/SrRuO_(3),both resonant band and asymmetry work *** one polarization direction,the BaSnO_(3)and SrTiO_(3)dielectric layers work together as barriers to provide considerable efficient barrier height for direct tunneling and lead to large tunneling *** the opposite polarization,the BaSnO_(3)layer serves as a quantum well to induce resonant tunneling across the barrier and considerably reduces the tunneling resistance of the ON *** integration of resonant band with asymmetry may provide a more efficient and applicable way to further improve the functionalities of FTJs.

关键词： polarization resonant tunneling

Synergistic effect of microwave irradiation and CaF2 on vanadium leaching

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 156-163页

作者： jing-peng Wang yi-min Zhang jing Huang Tao liu School of Resource and Environmental Engineering Wuhan University of Science and Technology Wuhan 430081 China Hubei Provincial Engineering Technology Research Center of High Efficient Cleaning Utilization for Shale Vanadium Resource Wuhan 430081 China Hubei Provincial Collaborative Innovation Center for High Efficient Utilization of Vanadium Resource Wuhan 430081 China

The effect and mechanism of microwave irradiation on vanadium leaching were studied via a comparison between microwave heating and conventional heating. The results show a synergistic effect of microwave irradiation and calcium fluoride （CaF2） on the vana- dium leaching efficiency. It is confirmed that the vanadium leaching process can be improved by microwave irradiation when CaF2 is present. The leaching rate of vanadium under microwave irradiation is increased by 8%-15% when 5wt% CaF2 is added; by contrast, in the absence of CaF2, the leaching rate is almost unaffected compared to that by conventional heating. Morphological analysis reveals that the particles are gradually eroded by acid under microwave irradiation, whereas some of the fine particles in samples subjected to conventional heating are tightly covered by a flocculent silicate product. Moreover, a large amount of A1 and V and a small amount of Si are dissolved from samples under microwave heating, as revealed by the elemental analysis of leachates. Fourier transform infrared spectroscopic analysis also indicates a higher mass transfer coefficient in the diffusion layer of the raw material by microwave irradiation. When CaF2 is present, the reaction energy barrier is lowered and the leaching process is controlled by the tightly covered product layer, resulting in a prominent effect of mi- crowave irradiation.

关键词： vanadium extraction leaching microwave irradiation calcium fluoride synergistic effects

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-jing Zhao jing Wang Zhong-yang Qi Hui-Qing liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient