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A review on DFACS(I):System design and dynamics modeling

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Chinese Journal of Aeronautics 2024年第5期37卷 92-119页

作者： Bohan JIAO Qifan liu Zhaohui DANG xiaokui YUE Yonghe ZHANG Yuanqing xia Li DUAN Qinglei HU Chenglei YUE Pengcheng WANG ming GUO Zhansheng DUAN Bing CUI Chu ZHANG xiaodong SHAO School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 710699China School of Automation Beijing Institute of TechnologyBeijing 100081China Institute of Mechanics Chinese Academy of SciencesBeijing 710043China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China School of Automation Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China

The Drag-Free and Attitude Control System(DFACS)is a critical platform for various space missions,including high precision satellite navigation,geoscience and gravity field measurement,and space scientific *** paper presents a comprehensive review of over sixty years of research on the design and dynamics model of ***,we examine the open literature on DFACS and its applications in Drag-Free missions,providing readers with necessary background information on the ***,we analyze the system configurations and main characteristics of different DFACSs,paying particular attention to the coupling mechanism between the system configuration and dynamics ***,we summarize the dynamics modeling methods and main dynamics models of DFACS from multiple perspectives,including common fundamentals and specific ***,we identify current challenges and technological difficulties in the system design and dynamics modeling of DFACS,while suggesting potential avenues for future *** paper aims to provide readers with a comprehensive understanding of the state-of-the-art in DFACS research,as well as the future prospects and challenges in this field.

关键词： Drag-Free DFACS System Design Dynamics Modeling Control design

Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin liu ming-Fu Lyu Heng-Yuan Zhang Jian-Ye liu Shi-Jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology

Fractal model of spontaneous imbibition in low-permeability reservoirs coupled with heterogeneity of pore seepage channels and threshold pressure

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Petroleum Science 2024年第2期21卷 1002-1017页

作者： ming-Sheng Zuo Hao Chen Xi-Liang liu Hai-Peng liu Yi Wu Xin-Yu Qi National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing102249China

Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability *** to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability reservoirs is extremely ***,traditional SI models based on single or averaged capillary tortuosity ignore the influence of heterogeneity of pore seepage channels and the threshold pressure(TP)on ***,in this work,based on capillary model and fractal theory,a mathematical model of characterizing SI considering heterogeneity of pore seepage channels is *** this basis,the threshold pressure was introduced to determine the pore radius at which the wetted phase can displace *** proposed new SI model was verified by imbibition experimental *** study shows that for weakly heterogeneous cores with permeability of 0-1 m D,the traditional SI model can characterize the imbibition process relatively accurately,and the new imbibition model can increase the coefficient of determination by 1.05 ***,traditional model has serious deviations in predicting the imbibition recovery for cores with permeability of 10-50 m *** new SI model coupling with heterogeneity of pore seepage channels and threshold pressure effectively solves this problem,and the determination coefficient is increased from 0.344 to 0.922,which is increased by2.68 *** low-permeability reservoirs,the production of the oil in transitional pores(0.01-0.1μm)and mesopores(0.1-1μm)significantly affects the imbibition recovery,as the research shows that when the heterogeneity of pore seepage channels is ignored,the oil recovery in transitional pores and mesopores decreases by 7.54%and 4.26%,*** analysis shows that increasing interfacial tension,decreasing contact angle,oil-water viscosity ratio and threshold pressure will increase imbibition *** addition,there are critical values for the influence of these factors o

关键词： Spontaneous imbibition Low-permeability reservoir Fractal model Threshold pressure Capillary tube

Transcription factor OsWRKY11 induces rice heading at low concentrations but inhibits rice heading at high concentrations

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Journal of Integrative Plant Biology 2024年第7期66卷 1385-1407页

作者： Lirong Zhao Yunwei liu Yi Zhu Shidie Chen Yang Du Luyao Deng Lei liu xia Li Wanqin Chen Zhiyu Xu Yangyang Xiong You ming Siyu Fang Ligang Chen Houping Wang Diqiu Yu CAS Key Laboratory of Tropical Plant Resources and Sustainable Use Xishuangbanna Tropical Botanical GardenThe Chinese Academy of SciencesMengla 666303China College of Life Sciences University of Chinese Academy of SciencesBeijing 101408China State Key Laboratory for Conservation and Utilization of Bio‐resources in Yunnan Yunnan UniversityKunming 650500China School of Life Sciences Yunnan UniversityKunming 650500China Southwest United Graduate School Yunnan UniversityKunming 650092China

The heading date of rice is a crucial agronomic characteristic that influences its adaptability to different regions and its productivity *** the involvement of WRKY transcription factors in various biological processes related to development,the precise mechanisms through which these transcription factors regulate the heading date in rice have not been well *** present study identified OsWRKY11 as a WRKY transcription factor which exhibits a pivotal function in the regulation of the heading date in rice through a comprehensive screening of a clustered regularly interspaced palindromic repeats(CRISPR)-CRISPR-associated nuclease 9 mutant library that specifically targets the WRKY genes in *** heading date of oswrky11 mutant plants and OsWRKY11-overexpressing plants was delayed compared with that of the wild-type plants under short-day and long-day *** investigation revealed that OsWRKY11 exerts dual effects on transcriptional promotion and suppression through direct and indirect DNA binding,*** normal conditions,OsWRKY11 facilitates flowering by directly inducing the expression of OsMADS14 and *** presence of elevated levels of OsWRKY11 protein promote formation of a ternary protein complex involving OsWRKY11,Heading date 1(Hd1),and Days to heading date 8(DTH8),and this complex then suppresses the expression of Ehd1,which leads to a delay in the heading *** investigation revealed that a mild drought condition resulted in a modest increase in OsWRKY11 expression,promoting ***,under severe drought conditions,a significant upregulation of OsWRKY11 led to the suppression of Ehd1 expression,ultimately causing a delay in heading *** findings uncover a previously unacknowledged mechanism through which the transcription factor OsWRKY11 exerts a dual impact on the heading date by directly and indirectly binding to the promoters of target genes.

关键词： heading date OsWRKY11 rice transcription factors

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Petroleum Science 2024年第4期21卷 2383-2392页

作者： Li-ming Zhao Cai-Ping Lu Yang liu Chao-Chao Li School of Mines China University of Mining and Technology Henan Institute of Geophysical Space Information

The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D) poroelastic model and the layered White model were investigated. This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale. For the inherent mechanism, both models resulted from quasi-static flow in a slow P-wave diffusion mode, and the differences between them originated from saturated fluids and boundary conditions. On the other hand, for the characteristic frequencies of the models, the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model. Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length. The differences between them were due to the diffusion length. The diffusion length for the 1D poroelastic model was determined by the sample length, whereas that for the layered White model was determined by the length of the representative elementary volume(REV). Subsequently, a numerical example was presented to demonstrate the similarities and differences between the models. Finally, published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole *** prediction of the combined model was in good agreement with the experimental data, thereby validating the effectiveness of the 1D poroelastic model. Furthermore, the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction, validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model. The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus d

关键词： 1D poroelastic model Layered White model Quasi-static flow Slow P-wave diffusion Characteristic frequency Diffusion length

Antibacterial Activity of Plants in Cirsium:A Comprehensive Review

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Chinese Journal of Integrative Medicine 2024年第9期30卷 835-841页

作者： TANG xiao-meng XIE ming-xia GOU Jun-li CHEN Liang TIAN Jin-long ZHANG xia LU You-yuan WANG Han-qing College of Pharmacy Ningxia Medical UniversityYinchuanNingxia750004China College of Traditional Chinese Medicine Hunan University of Chinese MedicineChangsha410007China General Hospital of Ningxia Medical University YinchuanNingxia750004China Ningxia Regional Characteristic Traditional Chinese Medicine Collaborative Innovation Center Co-constructed by the Province and Ministry Ningxia Engineering and Technology Research Center for Modernization of Regional Characteristic Traditional Chinese MedicineNingxia Medical UniversityYinchuan750004China Key Laboratory of Ningxia Minority Medicine Modernization Ministry of EducationYinchuan750004China

As ethnic medicine,the whole grass of plants in Cirsium was used as *** review focuses on the antimicrobial activity of plants in Cirsium,including antimicrobial components,against different types of microbes and bacteriostatic *** results showed that the main antimicrobial activity components in Cirsium plants were flavonoids,triterpenoids and phenolic acids,and the antimicrobial ability varied according to the species and the content of *** them,phenolic acids showed a strong antibacterial ability against Acinetobacter baumannii,Pseudomonas aeruginosa,and Enterococcus *** antibacterial mechanisms include:(1)damaging the cell membrane,cell walls,mitochondria and nucleus of bacteria;(2)inhibiting the synthesis of proteins and nucleic acids;(3)suppressing the synthesis of enzymes for tricarboxylic acid cycle pathways and glycolysis,and then killing the bacteria via inhibition of energy ***,most research results on antimicrobial activity of Cirsium plants are reported based on in vitro *** evidence from clinical data and comprehensive evaluation are needed.

关键词： Cirsium traditional use antibacterial active components bacteriostatic activity bacteriostatic mechanism Chinese medicine

Molecular insights into oil detachment from hydrophobic quartz surfaces in clay-hosted nanopores during steam-surfactant co-injection

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Petroleum Science 2024年第4期21卷 2457-2468页

作者： Ben-Jie-ming liu Xuan-Tong Lei Mohammadali Ahmadi Zhangxin Chen Department of Chemical and Petroleum Engineering University of Calgary Eastern Institute of Technology

Thermal recovery techniques for producing oil sands have substantial environmental impacts. Surfactants can efficiently improve thermal bitumen recovery and reduce the required amount of steam. Such a technique requires solid knowledge about the interaction mechanism between surfactants, bitumen,water, and rock at the nanoscale level. In particular, oil sands ores have extremely complex mineralogy as they contain many clay minerals(montmorillonite, illite, kaolinite). In this study, molecular dynamics simulation is carried out to elucidate the unclear mechanisms of clay minerals contributing to the bitumen recovery under a steam-anionic surfactant co-injection process. We found that the clay content significantly influenced an oil detachment process from hydrophobic quartz surfaces. Results reveal that the presence of montmorillonite, illite, and the siloxane surface of kaolinite in nanopores can enhance the oil detachment process from the hydrophobic surfaces because surfactant molecules have a stronger tendency to interact with bitumen and quartz. Conversely, the gibbsite surfaces of kaolinite curb the oil detachment process. Through interaction energy analysis, the siloxane surfaces of kaolinite result in the most straightforward oil detachment process. In addition, we found that the clay type presented in nanopores affected the wettability of the quartz surfaces. The quartz surfaces associated with the gibbsite surfaces of kaolinite show the strongest hydrophilicity. By comparing previous experimental findings with the results of molecular dynamics(MD) simulations, we observed consistent wetting characteristics. This alignment serves to validate the reliability of the simulation outcomes. The outcome of this paper makes up for the lack of knowledge of a surfactant-assisted bitumen recovery process and provides insights for further in-situ bitumen production engineering designs.

关键词： Clay minerals Bitumen Contact angle Interaction energy Surfactant Molecular dynamics

Anomalous response to creep deformation from dislocation density during electrically assisted creep aging

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Rare Metals 2024年第10期43卷 5268-5283页

作者： Chang Zhou Li-Hua Zhan Chun-Hui liu ming-Hui Huang College of Mechanical and Electrical Engineering Central South University Light Alloys Research Institute State Key Laboratory of Precision Manufacturing for Extreme Service PerformanceCentral South University

Adding numerous dislocations into metallic materials before the forming stage significantly enhances their deformability. However, this beneficial effect of dislocation defects may not have a simple monotonic relationship with increased dislocation density during electroplastic deformation. This is due to the complex interactions among the drifting electrons, dislocations and solute atoms. This study explores the effect of diverse initial dislocation densities on creep deformation during electrically aided creep aging of an aluminum–lithium alloy. Surprisingly, we discovered a threshold value for the dislocation density that affects electroplastic creep, i.e., an enhanced effect from dislocations weakens when exceeding this density threshold(an anomalous response to creep). Microstructural data also reveal that such an anomalous response originates mainly from differences in various dislocation density-tailored configurations, which can influence the dislocation motions and precipitation kinetics of the strengthening T1precipitates under the same action of pulsed currents. This study provides important insights into the dislocation density-mediated electroplastic creep of an aluminum–lithium alloy.

关键词： Al–Cu–Li alloy Creep aging Dislocation density Pulsed currents

Estimation of free core nutation parameters and availability of computing options

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Geodesy and Geodynamics 2024年第1期15卷 61-74页

作者： Weiwei Yang xia.ming Cui Jianqiao Xu Qingchao liu ming Qin State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China University of Chinese Academy of Sciences Beijing 100049China Hubei Luojia Laboratory Wuhan 430079China

The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance ***-precision superconducting gravimeter(SG) and very long baseline interferometry(VLBI) provide good observation techniques for detecting the FCN ***,some choices in data processing and solution procedures increase the uncertainty of the FCN *** this study,we analyzed the differences and the effectiveness of weight function and ocean tide corrections in the FCN parameter detection using synthetic data,SG data from thirty-one stations,and the 10 celestial pole offset(CPO) *** results show that significant discrepancies are caused by different computing options for a single SG *** stacking method,which results in a variation of0.24-5 sidereal days(SDs) in the FCN period(T) and 10^(3)-10^(4) in the quality factor(Q) due to the selection of the weighting function and the ocean tide model(OTM),can effectively suppress this *** statistical analysis results of synthetic data shows that although different weight choices,while adjusting the proportion of diurnal tidal waves involved,do not significantly improve the accuracy of fitted FCN parameters from gravity *** study evaluated a series of OTMs using the loading correction *** fitting of FCN parameters can be improved by selecting the mean of appropriate OTMs based on the evaluation *** the estimation of the FCN parameters based on the forced nutation,it was found that the weight function P_(1) is more suitable than others,and different CPO series(after 2009) resulted in a difference of 0.4 SDs in the T and of 103 in the *** estimated the FCN parameters for SG(T=430.4±1.5 SDs and Q=1.52×10^(4)±2.5×10^(3)) and for VLBI(T=429.8±0.7 SDs,Q=1.88×10^(4)±2.1×10^(3)).

关键词： Free core nutation Superconducting gravimeter Very long baseline interferometry Weight function Ocean tide model