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Chinese Journal of Chemical Engineering 2024年第5期69卷 167-176页

作者： Jinnan Guo Daoyin Liu Jiliang ma cai Liang Xiaoping Chen Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education Southeast UniversityNanjing 210096China

The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)*** details of the gas-solid flow behaviors of PCFB are *** on the gas-solid flow pattern,the particles tend to move more orderly under elevated *** an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient *** an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence *** back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient.

关键词： Pressurized circulating fluidized bed MP-PIC method Residence time distribution Axial dispersion coefficient

The NAC056 transcription factor confers freezing tolerance by positively regulating expression of CBFs and NIA1 in Arabidopsis

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Plant Communications 2024年第7期5卷 251-260页

作者： Peipei Xu Wei ma Huafeng Feng Weiming cai Laboratory of Photosynthesis and Environment CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesNo.300 Fenglin RoadShanghai 200032China State Key Laboratory of NBC Protection for Civilian Beijing 102205China Department of Food Science College of Hospitality ManagementShanghai Business SchoolShanghai 200235China These authors contributed equally to this article

Freezing stress can seriously affect plant growth and development,but the mechanisms of these effects and plant responses to freezing stress require further ***,we identified a NAM,ATAF1/2,and CUC2(NAC)-family transcription factor(TF),NAC056,that can promote freezing tolerance in ***056 mRNA levels are strongly induced by freezing stress in roots,and the nac056 mutant exhibits compromised freezing ***056 acts positively in response to freezing by directly promoting key C-repeat-binding factor(CBF)pathway ***,we found that CBF1 regulates nitrate assimilation by regulating the nitrate reductase gene NIA1 in plants;therefore,NAC056–CBF1–NIA1 form a regulatory module for the assimilation of nitrate and the growth of roots under freezing *** addition,35S::NAC056 transgenic plants show enhanced freezing tolerance,which is partially reversed in the cbfs triple ***,NAC056 confers freezing tolerance through the CBF pathway,mediating plant responses to balance growth and freezing stress tolerance.

关键词： CBFs freezing tolerance NAC transcription factor nitrate assimilation root growth

Age of Information for Short-Packet Covert Communication with Time Modulated Retrodirective Array

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China Communications 2024年第4期21卷 23-37页

作者： ma Yue ma Ruiqian Lin Zhi Yang Weiwei cai Yueming Miao Chen Wu Wen Key Laboratory of Near-Range RF Sensing ICs&Microsystems(NJUST) Ministry of EducationSchool of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China College of Electronic Engineering National University of Defense TechnologyHefei 230037China College of Communications Engineering Army Engineering University of PLANanjing 210007China

In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is designed to maximize the antenna gain in the target direction while the side lobe is sufficiently *** this basis,the covertness constraint and CAoI are derived in closed *** facilitate the covert transmission design,the transmit power and block-length are jointly optimized to minimize the CAoI,which demonstrates the trade-off between covertness and *** results illustrate that there exists an optimal block-length that yields the minimum CAoI,and the presented optimization results can achieve enhanced performance compared with the fixed block-length ***,we observe that smaller beam pointing error at Bob leads to improvements in CAoI.

关键词： age of information covert communication retrodirective array time modulation

Pore-scale water-gas distribution and gas permeability of natural gas hydrate reservoirs in the South China Sea

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Geoscience Frontiers 2024年第4期15卷 315-329页

作者： Yuxuan Xia Derek Elsworth Jianchao cai Cheng Lu Chao ma National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing 102249China Department of Energy and Mineral Engineering G3 Center and Energy InstituteThe Pennsylvania State UniversityUniversity Park 16802PAUnited States Guangzhou marine Geological Survey China Geological SurveyGuangzhou 510075China Center of Oil&Natural Gas Resource Exploration China Geological SurveyBeijing 100083China

Challenges in water drainage within natural gas hydrate reservoirs in the Shenhu area of the South China Sea,characterized by high clay content and strong hydrophilicity,significantly hinder natural gas *** the effects of gas pressure and liquid/gas saturation on gas permeability reveals essential insights for increasing gas production *** report gas displacement experiments on clayey-silt sediment samples,alongside X-ray computed tomography imaging,that reveal critical findings:a notable increase in flow rate and permeability as displacement pressure nears compaction pressure,highlighting the role of pressure management in enhancing recovery;water displacement from varying pore sizes under different pressures,highlighting the influence of pore size on fluid dynamics,and structural changes,including microfracture formation and a significant fracture that enlarges total pore space by about 15%,which collectively suggest methods to improve gas flow and ***,our analysis identifies average throat length,fractal dimension,and succolarity as principal controls on gas permeability,indicating the substantial impact of microstructural properties on extraction *** outcomes offer valuable strategies for optimizing natural gas hydrate reservoir development in the South China Sea,emphasizing the need for meticulous pressure and saturation control and in applying a deep understanding of microstructural dynamics.

关键词： Natural gas hydrate Clayey-silt sediments Gas saturation Gas permeability Microstructure

Microstructures,Deformation Mechanisms and Seismic Properties of Synkinematic Migmatite from Southeastern Tibet:Insights from the Migmatitic Core of the Ailao Shan-Red River Shear Zone,Western Yunnan,China

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Journal of Earth Science 2024年第4期35卷 1149-1169页

作者： Weiwei ma Bo Zhang Fulong cai Baoyou Huang Lei Zhang Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing100871China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100085China

Seismic anisotropy originating within the continental crust is commonly used to determine the deformation and kinematic flow within active orogens and is attributed to regionally oriented mica or hornblende ***,naturally deformed rocks usually contain compositional layers(e.g.,parallel compositional banding).It is necessary to understand how both varying mineral contents and differing intensities of compositional layering influence the seismic properties of the deep *** this study,we analyzed the seismic response of migmatitic amphibolite with compositional banding *** present the microstructures,fabrics,calculated seismic velocities,and seismic anisotropies of mylonitic amphibolite from a horizontal shear layer preserved within the Ailao Shan-Red River shear zone,southwestern Yunnan,*** investigated sample is characterized by pronounced centimeter-scale compositional *** microstructures and fabrics suggest that migmatitic amphibolite rocks within deep crust may delineate regions of deformation-assisted,channelized,reactive,porous melt *** origin of compositional banding in the studied migmatitic amphibolite is attributed primarily to partial melting together with some horizontal shearing *** microfabrics and structures investigated in this study are considered to be typical for the base of active horizontal shear layers in the deep crust of southeastern *** responses are modeled by using crystal preferred orientations for minerals of the migmatitic amphibolite by applying the Voigt-Reuss-Hill homogenization *** P-wave and S-wave velocities are largely consistent in the various layers of the ***,seismic anisotropies of P-wave(AV_(p))and S-wave(AVs)are higher in the melanosomes(AV_(p)=5.6%,AV_(s)=6.83%)than those in the leucosomes and the whole rock(AV_(p)=4.2%–4.6%,AV_(s)=3.1%–3.2%).In addition,there is pronounced,S-wave splitting oblique to the foliation plane in the migm

关键词： deformation-assisted melt flow seismic anisotropy microstructure compositional banding migmatite deep crust southeastern Tibet

Roughness characterization and shearing dislocation failure for rock-backfill interface

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International Journal of Minerals,Metallurgy and materials 2024年第6期31卷 1167-1176页

作者： Meifeng cai Zhilou Feng Qifeng Guo Xiong Yin Minghui ma Xun Xi Key Laboratory of High-Efficient Mine and Safety of Metal Mines of Ministry of Education Beijing 100083China Key Laboratory of Urban and Underground Space Engineering University of Science and Technology BeijingBeijing 100083China Shandong Gold Group Co LtdJinan 250102China

Shearing dislocation is a common failure type for rock–backfill interfaces because of backfill sedimentation and rock strata movement in backfill mining *** paper designed a test method for rock–backfill shearing *** digital image techno-logy and three-dimensional(3D)laser morphology scanning techniques,a set of 3D models with rough joint surfaces was ***,the mechanical behavior of rock–backfill shearing dislocation was investigated using a direct shear *** effects of interface roughness on the shear–displacement curve and failure characteristics of rock–backfill specimens were *** 3D fractal dimen-sion,profile line joint roughness coefficient(JRC),profile line two-dimensional fractal dimension,and the surface curvature of the frac-tures were *** correlation characterization of surface roughness was then analyzed,and the shear strength could be measured and calculated using *** results showed the following:there were three failure threshold value points in rock–backfill shearing dis-location:30%–50%displacement before the peak,70%–90%displacement before the peak,and 100%displacement before the peak to post-peak,which could be a sign for rock–backfill shearing dislocation *** surface JRC could be used to judge the rock–backfill shearing dislocation failure,including post-peak sliding,uniform variations,and gradient change,corresponding to rock–backfill disloca-tion failure on the field *** research reveals the damage mechanism for rock–backfill complexes based on the free joint surface,fills the gap of existing shearing theoretical systems for isomerism complexes,and provides a theoretical basis for the prevention and control of possible disasters in backfill mining.

关键词： rock–backfill roughness correlation characterization shearing dislocation interface failure

Study on trifluoromethanesulfonic acid-promoted synthesis of daidzein: Process optimization and reaction mechanism

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Chinese Journal of Chemical Engineering 2024年第7期71卷 132-139页

作者： Hai Cao Haibin Yang Yanxiong Fang Yuandi Zeng Xiaolan cai Jingjing ma School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,*** preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesizing daidzein was developed in this *** this article,a two-step synthesis of daidzein(Friedel–Crafts acylation and[5+1]cyclization)was developed via the employment of trifluoromethanesulfonic acid(TfOH)as an effective promoting *** effect of reaction conditions such as solvent,the amount of TfOH,reaction temperature,and reactant ratio on the conversion rate and the yield of the reaction,respectively,was systematically investigated,and daidzein was obtained in 74.0%isolated yield under optimal *** to the facilitating effect of TfOH,the Friedel–Crafts acylation was completed within 10 min at 90℃ and the[5+1]cyclization was completed within 180 min at 25℃.In addition,a possible reaction mechanism for this process was *** results of the study may provide useful guidance for industrial production of daidzein on a large scale.

关键词： Synthesis Optimal design Chemical processes Reaction mechanism

Promoted Non-enzymatic Glucose Sensor Based on Synergistic Effect of Hydrothermal Synthesized Ni(OH)_(2)-Graphene Nanocomposite

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Chemical Research in Chinese Universities 2024年第5期40卷 914-921页

作者： cai Yuqing CUI Qingyan ZHANG Huanrong ma Xinlei XUE Mianqi School of Chemistry and Life Resources Renmin University of ChinaBeijing100872P.R.China Technical Institute of Physics and Chemistry Chinese Academy of ScienceBeijing100190P.R.China

Although glucose electrochemical sensors based on enzymes play a dominant role in market,their stability remains a problem due to the inherent nature of ***,glucose sensors that are independent on enzymes have attracted more attention for the development of stable detection *** we present an enzyme-free glucose sensor based on Ni(OH)_(2)and reduced graphene oxide(rGO).The as-fabricated sensor still exhibits excellent electrocatalytic activity for detecting glucose under enzyme independent *** enhanced catalytic performance may due to synergistic effect as follows:(i)the interaction between the Ni2+andπelectron of graphene induces the formation of theβ-phase Ni(OH)_(2)with higher catalytic activity;(ii)the frozen dry process works as a secondary filtration,getting rid of poorly formed Ni(OH)_(2)particles with low catalytic activity;(iii)the rGO network with good conductivity provides a good electronic pathway for promoting electron transfer to reduce the response *** on the synergistic effect,the sensor exhibits a wide linear detection range from 0.2µmol/L to 1.0µmol/L and a low detection limit(0.1µmol/L,S/N=3).The excellent detection performance,as well as the easy and low-cost preparation method,suggests the promising applicability of the sensor in the glucose detection market.

关键词： Glucose sensing Non-enzyme sensor Graphene 2D material Ni(OH)_(2)nanosheet

Skin-inspired interface modification strategy toward a structurefunction integrated hybrid smart fabric system with self-powered sensing property for versatile applications

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Nano Research 2024年第9期17卷 8200-8208页

作者： Xiang Cheng Teng Chen De Gong Pengcheng ma Bo Chen Jun cai Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100190China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing U-Precision Tech Co. Ltd.Beijing 100176China University of Chinese Academy of Sciences Beijing 100049China

Fabric-based composites with superior mechanical properties and excellent perceptive function are highly ***,it remains a huge challenge to attain structure-function integration,especially for hybrid fabric ***,a skin-inspired interface modification strategy is proposed toward this target by constructing a hybrid smart fabric system consisting of two types of smart fabrics:carbon nanotube(CNT)/MXene-modified aramid fabrics and zinc oxide nanorod(ZnO NR)-modified carbon *** on that,flexible piezoelectric pressure sensors with skin-like hierarchical perception interfaces are fabricated,which demonstrate superb sensitivity of 2.39 V·kPa^(-1)and are capable of various wearable monitoring ***,the interface-modified hybrid fabric reinforced plastics can also be fabricated,which are proven to possess 13.6%higher tensile strength,10.1%elastic *** impressively,their average energy absorption can be improved by 111.9%,accompanied with inherent damage alert *** offers a paradigm to fabricate structure-function integrated hybrid smart fabric composites for the smart clothing and intelligent aerial vehicles.

关键词： hybrid fabrics interface modification piezoelectric pressure sensors self-diagnostic composites structure-function integration