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Journal of Advanced Dielectrics 2024年第2期14卷 54-62页

作者： Wanting shu Hong Li Yanli Huang Cong Lin Xiao Wu min Gao Tengfei Lin Chunlin zhao College of Materials Science and Engineering Fuzhou University Fuzhou 350108P.R.China College of Photonic and Electronic Engineering Fujian Normal University Fuzhou 350117P.R.China

In this work,the frequency dependence of ferroelectric and electrocaloric properties in barium titanate-based ceramics was studied based on Maxwell *** is found that the maximum and remnant polarization will decrease while the coercive field increases a lot with rising frequency from 0.1 to 10 Hz,indicating that polarization rotation and domain switching become difficult at high *** electrocaloric properties show the different frequency dependence at different phase *** entropy change(ΔS)and adiabatic temperature change(ΔT)are similar around/above Curie temperature(TCT,showing tiny frequency ***,ΔS andΔT display the obvious frequency dependence below T_(C),especially in the orthorhombic–tetragonal phase-transition region with a stable ferroelectric phase,and this frequency dependence becomes more obvious under a low-electric *** is also found that increasing the frequency can weaken the electric field dependence of electrocaloric *** work gives a general profile of frequency dependence for electrocaloric properties in ferroelectric ceramics.

关键词： Electrocaloric properties ferroelectric ceramics barium titanate frequency dependence

Amino acids TORC(talk)to anabolism through uncharged tRNA

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Science China(Life Sciences) 2024年第8期67卷 1775-1776页

作者： Zhen-Zhen Ma Shi-min zhao The Obstetrics&Gynecology Hospital of Fudan University State Key Laboratory of Genetic EngineeringShanghai Key Laboratory of Metabolic Remodelling and HealthFudan UniversityShanghai 200090China

Anabolism is essential for proliferation as well as to replenish dysfunctional macromolecules in *** to that both substantial building blocks and energy are required for anabolism,cells must double check whether these prerequisites are met before deciding to start *** acids are building blocks of protein synthesis,their sufficiency in cells is closely monitored by several mechanisms,which all are linked to protein synthesis.

关键词： synthesis. synthesis deciding

Anti-aging performance improvement and enhanced combustion efficiency of boron via the coating of PDA

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Defence Technology（防务技术） 2024年第3期33卷 399-410页

作者： shuai Ma Qinghai shu Mengyang Zhang Hongyu Huang Yansong Shi Xijuan Lv shuai zhao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement(MOE) Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of TechnologyBeijing100081China Tangshan Research Institute of Beijing Institute of Technology Tangshan063000HebeiChina

Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during *** polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of *** results indicated that the PDA coating formed a fishing net structure on the surface of boron *** heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw ***,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw ***,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were *** was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,*** peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@***,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites.

关键词： Boron particles Polydopamine Anti-aging performance improvement Heat release

Aerodynamic/stealth design of S-duct inlet based on discrete adjoint method

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 725-746页

作者： Jun DENG Ke zhao Lin ZHOU Wei ZHANG Bowen shu Jiangtao HUANG Zhenghong GAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aerospace Technology Institute of China Aerodynamic Research and Development CenterMianyang 621000Sichuan ProvinceChina

It is a major challenge for the airframe-inlet design of modern combat aircrafts,as the flow and electromagnetic wave propagation in the inlet of stealth aircraft are very *** this study,an aerodynamic/stealth optimization design method for an S-duct inlet is *** upwind scheme is introduced to the aerodynamic adjoint equation to resolve the shock wave and flow *** multilevel fast multipole algorithm(MLFMA)is utilized for the stealth adjoint equation.A dorsal S-duct inlet of flying wing layout is optimized to improve the aerodynamic and stealth *** the aerodynamic and stealth characteristics of the inlet are effectively ***,the optimization results are analyzed,and it shows that the main contradiction between aerodynamic characteristics and stealth characteristics is the centerline and crosssectional *** S-duct is smoothed,and the cross-sectional area is increased to improve the aerodynamic characteristics,while it is completely opposite for the stealth *** radar cross section(RCS)is reduced by phase cancelation for low frequency *** method is suitable for the aerodynamic/stealth design of the aircraft airframe-inlet system.

关键词： S-duct inlet aerodynamic/stealth optimization design discrete adjoint upwind scheme multilevel fast multipole algorithm(MLFMA)

Kinetic study and DFT calculation on the tetracycline abatement by peracetic acid

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Chinese Chemical Letters 2024年第9期35卷 346-350页

作者： Dan-Ying Xing Xiao-Dan zhao Chuan-shu He Bo Lai College of Chemical Engineering Huaqiao UniversityXiamen 361021China State Key Laboratory of Hydraulics and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China

Water contamination by tetracycline(TC)has emerged as an environmental concern owing to its widespread use and antibiotic *** of peracetic acid(PAA)in the water and wastewater treatment has recently been proposed and demonstrated to be effective for TC abatement,yet the underlying reaction kinetics between the PAA and TC are not yet *** explore the reaction kinetics,the effect of solution pH on TC abatement by PAA is studied and the species-specific rate constants are *** ability to donate and accept electrons for different species of TC and PAA is evaluated via density functional theory(DFT)*** pH-dependent apparent second-order rate constants of TC abatement by PAA exhibits the parabolic shape with the maximum at p H 8.5(9.75 L mol^(-1)s^(-1)).This phenomenon is closely related to the speciation of TC and PAA,in which the reaction between PAAH and TTC^(2-)possesses the highest species-specific rate constants according to the kinetic *** DFT calculations suggest that the HOMO of TTCH^(+),TTC,TTC^(-),TTC^(2-)and the LUMO of PAAH and PAA-are–6.40,–6.26,–5.10,–4.94 e V and–0.24,0.60 e V,*** to the DFT calculations,deprotonation of TC and PAA leads to an increase of the HOMO value of TC and the LUMO value of ***,the HOMOTC–LUMOPAAvalues is in good agreement with the trend of species-specific rate constants,which can be used to evaluate the reactivity between PAA and TC with different *** study provides the kinetic data and theoretical basis for the reaction of PAA and TC,which is critical for the application of PAA in the treatment of water and wastewater.

关键词： Peracetic acid Tetracycline Kinetics Rate constants DFT calculation

RNAirport:a deep neural network-based database characterizing representative gene models inplants

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Journal of Genetics and Genomics 2024年第6期51卷 652-664页

作者： Sitao Zhu shu Yuan Ruixia Niu Yulu Zhou zhao Wang Guoyong Xu State Key Laboratory of Hybrid Rice Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China Hubei Hongshan Laboratory WuhanHubei 430070China

A 5'-leader,known initially as the 5'-untranslated region,contains multiple isoforms due to alternative splicing(aS)and alternative transcription start site(aTSS).Therefore,a representative 5'-leader is demanded to examine the embedded RNA regulatory elements in controlling translation ***,we develop a ranking algorithm and a deep-learning model to annotate representative 5'-leaders for five plant *** rank the intra-sample and inter-sample frequency of aS-mediated transcript isoforms using the Kruskal-Wallis test-based algorithm and identify the representative aS-5'-*** further assign a representative 5'-end,we train the deep-learning model 5'leaderP to learn aTsS-mediated 5'-end distribution patterns from cap-analysis gene expression *** model accurately predicts the 5'-end,confirmed experimentally in Arabidopsis and *** representative 5'-leader-contained gene models and 5'leaderP can be accessed at RNAirport(http:/***/leader5P/).The Stage 1 annotation of 5'-leader records 5'-leader diversity and will pave the way to Ribo-Seq open-reading frame annotation,identical to the project recently initiated by human GENCODE.

关键词： 5'-leader Transcript isoforms RNA regulatory elements UORF Deep learning Synthetic biology Translational control

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu shu-sen Cheng Yu-qing Xue Xiao-man Cheng zhao Liu University of Science and Technology Beijing Beijing 100083China ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Rapid profiling rock mass quality underneath tunnel face for Sichuan-Xizang Railway

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Underground Space 2024年第6期19卷 138-152页

作者： Siyuan Wu min Qiu zhao Yang Fuquan Ji Zhongqi Quentin Yue Department of Civil Engineering The University of Hong KongHong Kong 999077China CCCC Second Harbor Engineering Company Ltd. Wuhan 430000China Research and Development Center of Transport Industry of Intelligent Manufacturing Technologies of Transport Infrastructure Wuhan 430000China

The Sichuan-Xizang Railway is a global challenge,surpassing other known railway projects in terms of geological and topographical *** paper presents an approach for rapidly profiling rock mass quality underneath tunnel face for the ongoing construction of the Sichuan-Xizang *** adopts the time-series method and carries out the quantitative analysis of the rock mass quality using the depth-series measurement-while-drilling(MWD)data associated with drilling of blastholes.A tunnel face with 15 blastholes is examined for *** results include identification of the boundary of homogeneous geomaterial by plotting the blasthole depth against the net drilling time,as well as quantification of rock mass quality through the recalculation of the new specific *** new specific energy profile is compared and highly consistent with laboratory test,manual logging and tunnel seismic prediction *** consistency can enhance the blasthole pattern design and facilitate the dynamic determination of charge placement and *** paper highlights the importance of digital monitoring during blasthole drilling for rapidly profiling rock mass quality underneath and ahead of tunnel *** upgrades the MWD technique for rapid profiling rock mass quality in drilling and blasting tunnels.

关键词： Measurement-while-drilling Drilling and blasting Rock mass quality New specific energy Constant penetration rate Sichuan-Xizang railway Tunnelling

QoS-Aware Computation Offloading in LEO Satellite Edge Computing for IoT:A Game-Theoretical Approach

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Chinese Journal of Electronics 2024年第4期33卷 875-885页

作者： Ying CHEN Jintao HU Jie zhao Geyong min School of Computer Science Beijing Information Science and Technology University University of Exeter

Low earth orbit(LEO) satellite edge computing can overcome communication difficulties in harsh environments, which lack the support of terrestrial communication infrastructure. It is an indispensable option for achieving worldwide wireless communication coverage in the future. To improve the quality-of-service(QoS) for Internet-of-things(IoT) devices, we combine LEO satellite edge computing and ground communication systems to provide network services for IoT devices in harsh environments. We study the QoS-aware computation offloading(QCO) problem for IoT devices in LEO satellite edge computing. Then we investigate the computation offloading strategy for IoT devices that can minimize the total QoS cost of all devices while satisfying multiple constraints, such as the computing resource constraint, delay constraint, and energy consumption constraint. We formulate the QoSaware computation offloading problem as a game model named QCO game based on the non-cooperative competition game among IoT devices. We analyze the finite improvement property of the QCO game and prove that there is a Nash equilibrium for the QCO game. We propose a distributed QoS-aware computation offloading(DQCO) algorithm for the QCO game. Experimental results show that the DQCO algorithm can effectively reduce the total QoS cost of IoT devices.

关键词： Satellites Costs Computational modeling Low earth orbit satellites Quality of service Games Nash equilibrium

An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming Liang Guangning Li min Xu Junmin zhao Feng Hao Hongbo Shi Northwestern Polytechnical University School of Astronautics Xi’an 710072China China North Industries Group Corporation No 203 Research Institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is *** proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application ***,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is *** order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried *** simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight ***,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy *** intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight *** with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability *** intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid