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Agricultural Sciences in China 2009年第8期8卷 972-978页

作者： CHEN Yong ZHENG Wei WANG Li-ming CUI Hai-lan LI Guo-xi liuxin-gui HAN Cheng-chou ZENG Ren-sen Weed Science Laboratory College of Agriculture South China Agricultural University Guangzhou 510642 P.R.China Department of Weed and Rodent Biology and Management Institute of Plant Protection Chinese Academy of Agricultural SeieneesBeijing 100193 P.R.China

Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxicity of the fungal fermented broth was evaluated through the bioassay and the active ingredients were preliminarily isolated by using silica gel column chromatography （CC） in this study. The most active fraction 5-Ⅲ was obtained and analyzed by gas chromatography-mass spectrometry （GC-MS）. The results show that 5-Ⅲ consisted of many compounds, in which 36 compounds accounted for 94.24% of total peak area. Di-n-butyl phthalate （DBP） displayed the highest activity accounted for 9.24% of the total peak area, suggesting that DBP may be one of the main active compounds produced by E. monoceras.

关键词： Exserohilum monoceras phytotoxin active ingredients Echinochloa crus-galli

A new twist to the interplay between superconductivity and Kondo correlation

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 1-2页

作者： gui-Lu Long Department of Physics Tsinghua UniversityBeijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Recently,Deng et al.[1] found a new twist to the intriguing physics resulting from the interplay between Kondo correlation and *** correlation [2,3] and superconductivity [4,5] are two fundamental phenomena in condens... 详细信息

关键词： Kondo twist

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Numerical investigation and modeling of sweep effects on inlet flow field of axial compressor cascades

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Chinese Journal of Aeronautics 2024年第2期37卷 296-308页

作者： Jiancheng ZHANG Donghai JIN Xingmin gui School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institue of Beihang University Nanchang 330096China

Swept blades are widely utilized in transonic compressors/fans and provide high load,high through-flow,high efficiency,and adequate stall ***,there is limited quantitative research on the mechanism of the effect of swept blades on the flow field,resulting in a lack of direct quantitative guidance for the design and analysis of swept blades in fans/*** better understand this mechanism,this study employs a reduced-dimensional force equilibrium method to analyze more than 1500 swept cascades *** verify that circumferential fluctuation terms are responsible for inducing radial migration in the inlet airflow field of the swept blade,resulting in variations in the incidence angle and consequently leading to changes in the characteristics of the swept ***,a combination of simple functions and machine learning is utilized to model the circumferential fluctuation terms and quantify the sweep *** prediction accuracy of the model is high,with coefficient of determination greater than 0.95 on the test *** the model is applied in a meridional flow analysis program,the calculation accuracy of the program for the incidence angle is improved by 0.4°and 0.6°at the design and off-design conditions respectively,compensating for the program’s original ***,the model can also provide quantitative guidance for the design of swept blades,thereby reducing the number of design iterations and improving design efficiency.

关键词： Turbomachinery Sweep aerodynamics Quasi-3D method Incidence angle Circumferential fluctuation Machine learning

Robust Feedback Set Stabilization of Logic Networks with State-Dependent Uncertain Switching and Control Constraints

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Journal of Systems Science & Complexity 2024年第2期37卷 629-646页

作者： DAI Chaoqun GUO Yuqian gui Weihua School of Automation Central South UniversityChangsha 410083China

This study investigates the robust feedback set stabilization of switched logic control networks(SLCNs)with state-dependent uncertain switching and control ***,based on the properties of the semi-tensor product of matrices and the vector representation of logic,an SLCN with state-dependent uncertain switching and control constraints is expressed in algebraic ***,an input transformation and a switching model are constructed to transfer the original SLCN into one with a free control input and arbitrary *** equivalence between the set stabilizability of the original SLCN and that of the resulting SLCN is *** on such equivalence,the authors propose a necessary and sufficient condition for robust feedback set ***,an example is presented to demonstrate the application of the results obtained.

关键词： Input transformation robust control invariant subset robust feedback set stabilizability semi-tensor product state-dependent constraints switched logic control network

Bianjing Spectacle: Soundscapes of Bianjing and Identities in Song Dynasty Literature

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2024年第1期18卷 77-102页

作者： LI gui School of Humanities Shanghai Normal UniversityShanghai 200234China

By closely examining the literary works of the Song Dynasty,such as prose,poetry,rhyme-prose,lyrics,notes,and miscellaneous theses,this paper combines historical and literary evidence to rediscover the 13 types of soundscapes and their corresponding spaces in the Bianjing City,the capital of the Northern Song Dynasty,and it reveals the causes and historical-cultural significance of these *** on the key issues of soundscapes,this paper analyzes the sound spaces,identities,discourses,and literary achievements depicted in the writings about *** argues that the“Bianjing Spectacle”of vendors’cries described by the Southern Song people can be used as a summary of the soundscape characteristics of ***,it interprets the special silence,crying,and the absence of the sounds of production from an aesthetic *** rediscovering,analyzing,and interpreting the soundscapes of Bianjing,this paper reveals significant differences between the Tang and Song dynasties at the sound level and differentiates various“auditory communities.”It thereby demonstrates the portrayal of Bianjing in Song literature,addresses theoretical hot topics in literature and geography,and builds on Marx’s arguments to propose that a thorough understanding of history,the world,and ourselves requires an in depth study of the soundscapes in literature.

关键词： Song literature Bianjing in the Northern Song Dynasty soundscapes identities transformation during the Tang and Song dynasties

Synthesis of a High-Efficiency Demulsifier and Study on Optimal Demulsification Conditions

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 107-115页

作者： Zhu Shuai Zhang YingYu gui Xia College of Chemical Engineering Nanjing Tech University30 Puzhunan RoadNanjing 211816China

Oil and water separation has always been a top priority in the oil *** this study,a series of hyperbranched fluorinated polyamine-amine polymers(HFPA1-5)were synthesized directly using an improved“one-pot method.”The highly active fluorinated p-trifluoromethylaniline was used as the core raw material,while diethylenetriamine and methyl acrylate were used as the chain segment.A hyperbranched fluorine-containing polyamine-amine demulsifier(NHFPA6)was obtained through nano-grafting copolymerization of *** enhance the demulsification and dehydration performance,the copolymerized HFPA6 was modified and ***,the effects of the combination ratio,demulsifier concentration,demulsification time,and demulsification temperature on the demulsification effect were *** results revealed that a combination ratio of DE-401:NHFPA6=1:1,a demulsification temperature of 50℃,a demulsification time of 60 min,and a demulsifier concentration of 150 mg/L yielded a dehydration rate as high as 99.80%.A response surface optimization design of demulsification conditions was *** model verified that the optimal demulsification conditions were 50℃,300 mg/L,and 90 ***,considering the economic benefits of factories,it is more favorable to select demulsification conditions with a shorter time and lower concentration when the dehydration standard is ***,the demulsification conditions were selected as 50℃,150 mg/L,and 60 *** to existing demulsifiers,the demulsifier developed in this study exhibits a lower demulsification temperature and higher demulsification efficiency.

关键词： hyperbranched fluorinated polyamine-amine nano-SiO_(2)

Formation Characteristics of CO_(2) Hydrates in the Presence of Porous Media and NaCl

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 168-177页

作者： Han Jianchao Zhu Shuai gui Xia College of Chemical Engineering Nanjing Tech UniversityNanjing 211816China

Hydrate-based CO_(2) sequestration is an effective method for reducing the greenhouse effect,and the presence of porous media and NaCl can impact the formation characteristics of *** study uses the constant volume temperature search method to investigate the effects of quartz sand particle size(0.006‒0.03 mm),water saturation(30%–90%),and NaCl concentration(1%‒9%)on the phase equilibrium and kinetics of CO_(2) hydrates within a temperature range of 273‒285 K and pressure range of 1.0‒3.5 *** results indicate that a decrease in quartz sand particle size or an increase in NaCl concentration shifts the hydrate phase equilibrium curve towards lower temperatures and higher pressures,making hydrate generation conditions more *** different particle size systems,there are no significant changes in the rate of CO_(2) hydrate formation or conversion *** highest hydrate conversion rate of 71.1%is observed in a 0.015 mm particle size *** increasing water saturation,both the generation rate and conversion rate of CO_(2) hydrates show a trend of first increasing and then ***,low concentrations of NaCl(1%–3%)are found to enhance the formation and conversion rates of CO_(2) ***,as NaCl concentration increases,the rate of CO_(2) hydrate formation and conversion rate decrease.

关键词： CO_(2)hydrate porous medium NaCl formation characteristics

Evolutionary mechanisms and practical significance of reproductive success and clonal diversity in unisexual vertebrate polyploids

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Science China(Life Sciences) 2024年第3期67卷 449-459页

作者： Meng Lu Li Zhou Jian-Fang gui State Key Laboratory of Freshwater Ecology and Biotechnology Hubei Hongshan Laboratorythe Innovation Academy of Seed DesignInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China

Unisexual reproduction is generally relevant to polyploidy, and unisexual vertebrates are often considered an evolutionary “dead end” due to the accumulation of deleterious mutations and absence of genetic diversity. However, some unisexual polyploids have developed strategies to avoid genomic decay, and thus provide ideal models to unveil unexplored evolutionary mechanisms, from the reproductive success to clonal diversity creation. This article reviews the evolutionary mechanisms for overcoming meiotic barrier and generating genetic diversity in unisexual vertebrates, and summarizes recent research advancements in the polyploid Carassius complex. Gynogenetic gibel carp(Carassius gibelio) is a unique amphitriploid that has undergone a recurrent autotriploidy and has overcome the bottleneck of triploid sterility via gynogenesis. Recently, an efficient strategy in which ploidy changes, including from amphitriploid to amphitetraploid, then from amphitetraploid to novel amphitriploid, drive unisexual-sexual-unisexual reproduction transition and clonal diversity has been *** on this new discovery, multigenomic reconstruction biotechnology has been used to breed a novel strain with superior growth and stronger disease resistance. Moreover, a unique reproduction mode that combines both abilities of ameiotic oogenesis and sperm-egg fusion,termed as ameio-fusiongensis, has been discovered, and it provides an efficient approach to synthesize sterile allopolyploids. In order to avoid ecological risks upon escape and protect the sustainable property rights of the aquaculture seed industry, a controllable fertility biotechnology approach for precise breeding is being developed by integrating sterile allopolyploid synthesis and gene-editing *** review provides novel insights into the origin and evolution of unisexual vertebrates and into the attempts being made to exploit new breeding biotechnologies in aquaculture.

关键词： unisexual vertebrates polyploidy reproduction transition clonal diversity precise breeding genomic reconstruction controllable fertility

Effect of Ti and Ta content on the oxidation resistance of Co-Ni-based superalloys

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 351-361页

作者： Yuheng Zhang Zixin Li Yunwei gui Huadong Fu Jianxin Xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

Co-Ni-based superalloys are known for their capability to function at elevated temperatures and superior hot corrosion and thermal fatigue ***,these alloys show potential as crucial high-temperature structural materials for aeroengine and gas turbine hot-end *** previous work elucidated the influence of Ti and Ta on the high-temperature mechanical properties of ***,the intricate interaction among elements considerably affects the oxidation resistance of *** this paper,Co-35Ni-10Al-2W-5Cr-2Mo-1Nb-xTi-(5−x)Ta alloys(x=1,2,3,4)with varying Ti and Ta contents were designed and compounded,and their oxidation resistance was investigated at the temperature range from 800 to 1000℃.After oxidation at three test conditions,namely,800℃for 200 h,900℃for 200 h,and 1000℃for 50 h,the main structure of the oxide layer of the alloy consisted of spinel,Cr_(2)O_(3),and Al_(2)O_(3)from outside to *** consisting of Ta,W,and Mo formed below the Cr_(2)O_(3)*** interaction of Ti and Ta imparted the highest oxidation resistance to 3Ti2Ta ***,an excessive amount of Ti or Ta resulted in an adverse effect on the oxidation resistance of the *** study reports the volatilization of W and Mo oxides during the oxidation process of Co-Ni-based cast superalloys with a high Al content for the first time and explains the formation mechanism of holes in the oxide *** results provide a basis for gaining insights into the effects of the interaction of alloying elements on the oxidation resistance of the alloys they form.

关键词： Co-Ni-based superalloys high-temperature oxidation Ti and Ta elements formation mechanism of holes

Multimodal Data-Driven Reinforcement Learning for Operational Decision-Making in Industrial Processes

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 252-254页

作者： Chenliang Liu Yalin Wang Chunhua Yang Weihua gui the School of Automation Central South UniversityChangsha 410083China IEEE

Dear Editor, This letter proposes a multimodal data-driven reinforcement learning-based method for operational decision-making in industrial processes. Due to the frequent fluctuations of feedstock properties and operating conditions in the industrial processes, existing data-driven methods cannot effectively adjust the operational variables. In addition, multimodal data such as images, audio.

关键词： processes modal adjust