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From Acta Botanica Sinica to jIPB:Connecting Chinese Plant Science with the International Community for 60 Years

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journal of Integrative Plant Biology 2012年第10期54卷 678-681页

作者： Chun-Ming liu Institute of Botany the Chinese Academy of Sciences Beijing China

In 1952, when botany was still regarded as a ＂new science＂ in China, a quarterly journal named Acta Botanica Sinica （ABS） was established by the Botanical Society of China. Dr. Shih- Wei Loo received his Ph.D. from the California Institute of Technology （CIT） in 1945, and was appointed as the journal＇s first Editor-in-Chief for his achievements in plant biology （Tang and Loo 1940; Loo and Wang 1943）. Since then, the journal has continuously nourished the growth of many Chinese botanists, except for a 5-year hiatus during the arduous Cultural Revolu- tion period between 1967 and 1972. By 1989, the journal began publishing monthly.

关键词： BOTANICAL research BOTANY -- Periodicals SOCIAL groups PERIODICAL publishing PUBLISHERS & publishing

Passive inter-modulation scattering analysis of reflector considering contact nonlinearity

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Chinese journal of Aeronautics 2013年第2期26卷 463-469页

作者： jiang jie Li Tuanjie liu Yicai School of Electromechanical Engineering Xidian University

Passive inter-modulation （PIM） is a form of nonlinear distortion caused by the inherent nonlinearities of the passive devices and components in RF/microwave system. It will degenerate the performance of communication system with broad-band channel and high-sensitivity receiver. Therefore, it is necessary to construct a model to simulate this process in order to predict the level of PIM. This paper is aimed at constructing some plate models with one-dimensional and two-dimensional contact nonlinearity sections illuminated by two-tone waves, and calculating the scattered field at a fixed-point in space using time-domain physical optics method. By taking fast Fourier transform （FFT）, we get the spectrum of the scattered field and then analyze the generated PIM products. At the end of this paper, some numerical examples are presented to show the influence rules of the relative factors on PIM. The results indicate the variation of the level of PIM with the number of the nonlinear regions, the nonlinear spacing, and the incident power levels.

关键词： Contact nonlinearity Nonlinear distortion Passive inter-modulation Reflector antennas Scattered field Time-domain physical optics

Structure of high spin state in proton-rich ^(74,76,78)Kr isotopes:A projected shell model description

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Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 32-37页

作者： liu YanXin YU ShaoYing SHEN CaiWan School of Science Huzhou Teachers College

The N≈z nuclei in the mass A^80 region has been researched because of an abundance of nuclear structure *** projected shell model(PSM)was adopted to investigate the structure of high spin state in proton-rich 74,76,78Kr isotopes including yrast spectra,moment of inertia,electric quadrupole transitions and the behavior of single *** calculated results are in good agreement with available data and the shape coexistence in low-spin is also discussed.

关键词： projected shell model high spin state moment of inertia electric quadrupole transition

Screening the anti-gout traditional herbs from TCM using an in vitro method

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Chinese Chemical Letters 2016年第11期27卷 1701-1707页

作者： Wei-jia Chen Yi Wu Xin zhao Shu liu Feng-Rui Song zhong-Ying liu zhi-Qiang liu School of Pharmaceutical Sciences Jilin University National Center of Mass Spectrometry in Changchun & jilin Province Key Laboratory of Chinese Medicine Chemistry and Mass Spectrometry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The aim of this work was to evaluate the ability of 33 herbal extracts in inhibiting the acute inflammation and xanthine oxidase （XOD） activity. The anti-inflammation effects of the herbal extracts were detected by an in vitro cell model, which was established by stimulating human umbilical vein endothelial cells （HUVEC） using sodium urate （MSU）. In this model, the intercellular adhesion molecule-1 （ICAM-1） and interleukin-1 beta （IL-1β） were expressed, and the anti-inflammation effects of herbal extracts were evaluated by detecting the content changes of ICAM-1 and IL-1β in cell lysates and cell culture supernates using an enzyme-linked immunosorbent assay （ELISA）. Moreover, an ultrahigh performance liquid chromatography and tandem mass spectrometry （UPLC-MS/MS） method was used for the detection of XOD activity and the screening of XOD inhibitors in this research. The amount of uric acid from each analyte was directly detected using the multiple reaction monitoring mode and the uric acid level could be reduced via the addition of an inhibitor. Results indicated that Salviae Miltiorrhizae Radix et Rhizome, Rhei Radix et Rhizoma, Polygoni Cuspidati Rhizoma et Radix, Selaginellae Herba, Paeoniae Radix Rubra, especially Ginkgo Folium seemed to be more effective in anti-inflammation and inhibiting XOD activity. The anti-inflammation and enzyme inhibitory activities of the herbal extracts may be correlated with their bioactive components. And the differences between the herbal extracts were correlated with the amount of flavonoid and anthraquinone components. In our study, we have investigated the potential anti-inflammation bioactivity of 33 herbal extracts in vitro, which could provide a reference for further in vivo research in the orevention and treatment of gout.

关键词： Gout Inflammation Human umbilical vein endothelial cells Xanthine oxidase UPLC-MS/MS

Dynamics modeling and control of a transport aircraft for ultra-low altitude airdrop

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Chinese journal of Aeronautics 2015年第2期28卷 478-487页

作者： liu Ri Sun Xiuxia Dong Wenhan Aeronautics and Astronautics Engineering College Air Force Engineering University

The nonlinear aircraft model with heavy cargo moving inside is derived by using the sep- aration body method, which can describe the influence of the moving cargo on the aircraft attitude and altitude accurately. Furthermore, the nonlinear system is decoupled and linearized through the input^utput feedback linearization method. On this basis, an iterative quasi-sliding mode （SM） flight controller for speed and pitch angle control is proposed. At the first-level SM, a global dynamic switching function is introduced thus eliminating the reaching phase of the sliding motion. At the second-level SM, a nonlinear function with the property of ＂smaUer errors correspond to bigger gains and bigger errors correspond to saturated gains＂ is designed to form an integral sliding manifold, and the overcompensation of the integral term to big errors is weakened. Lyapunov- based analysis shows that the controller with strong robustness can reject both constant and time-varying model uncertainties. The performance of the proposed control strategy is verified in a maximum load airdrop mission.

关键词： Dynamics modeling Feedback liaearization Flight control Nonlinear system Sliding mode control Uncertainty

Study on Dendritic Growth in Pressurized Solidification of Mg–Al Alloy Using Phase Field Simulation

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journal of Materials Science & Technology 2016年第1期32卷 68-75页

作者： Haowei Pan zhiqiang Han Baicheng liu Key Laboratory for Advanced Materials Processing Technology Ministry of EducationSchool of Materials Science and EngineeringTsinghua University State Key Laboratory of Automotive Safety and Energy Department of Automotive EngineeringTsinghua University

A multi-grain phase field model coupled with thermodynamic calculation was adopted to describe the dendritic growth in pressurized solidification of Mg-A1 alloy during squeeze casting, in which the effects of the pressure on the Gibbs free energy and chemical potential of solid and liquid phases, the solute diffusion coefficient, and the solute partition coefficient were considered. The individual effect of solute diffusion coefficient, and the Gibbs free energy on the dendritic growth was studied. With the compar- ison of the dendritic growth under atmospheric and elevated pressures, the effect of pressure on the microstructure evolution was discussed. The results showed that the grains are refined, the dendritic growth rate tends to increase and the secondary dendrite arms are more developed as the pressure is increased from 0.1 to 100 MPa, which showed a good agreement with the experimental results of direct squeeze casting of Mg-AI alloy. As the pressure increases, the largest dendritic growth rate can be obtained under the pressure between 200 and 250 MPa, while the growth rate decreases with a further increase of pressure.

关键词： Phase field Pressurized solidification Dendritic growth Mg-Al alloy Gibbs free energy

Spectroscopic Evidence for Electron Correlations in Epitaxial Bilayer Graphene with Interface-Reconstructed Superlattice Potentials

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Chinese Physics Letters 2022年第7期39卷 74-80页

作者： Chaofei liu jian Wang International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Beijing Academy of Quantum Information Sciences Beijing 100193China

Superlattice potentials are theoretically predicted to modify the single-particle electronic structures. The resulting Coulomb-interaction-dominated low-energy physics would generate highly novel many-body phenomena. Here,by in situ tunneling spectroscopy, we show the signatures of superstructure-modulated correlated electron states in epitaxial bilayer graphene(BLG) on 6H-Si C(0001). As the carrier density is locally quasi-‘tuned’ by the superlattice potentials of a 6 × 6 interface reconstruction phase, the spectral-weight transfer occurs between the two broad peaks flanking the charge-neutral point. Such a detected non-rigid band shift beyond the single-particle band description implies the existence of correlation effects, probably attributed to the modified interlayer coupling in epitaxial BLG by the 6×6 reconstruction as in magic-angle BLG by the moiré potentials. Quantitative analysis suggests that the intrinsic interface reconstruction shows a high carrier tunability of ~1/2 filling range, equivalent to the back gating by a voltage of ~70 V in a typical gated BLG/SiO_(2)/Si device. The finding in interfacemodulated epitaxial BLG with reconstruction phase extends the BLG platform with electron correlations beyond the magic-angle situation, and may stimulate further investigations on correlated states in graphene systems and other van der Waals materials.

关键词： BLG red profile STM Spectroscopic Evidence for Electron Correlations in Epitaxial Bilayer Graphene with Interface-Reconstructed Superlattice Potentials Graphene

Environmental benefits and farmers' adoption of winter cover crops in the North China Plain

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Pedosphere 2024年第1期34卷 159-169页

作者： Shufang GUO Yitao zHANG Limei zHAI jian liu Hongyuan WANG Hongbin liu State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Key Laboratory of Nonpoint Source Pollution ControlMinistry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural SciencesKunming 650205China Shandong Yucheng Agro-ecosystem National Observation Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China The Norwegian Institute of Bioeconomy Research(NIBIO) Akershus 1431Norway

The introduction of cover crops into monoculture systems to improve soil health has been widely adopted worldwide. However, little is known about the environmental risks and application prospects of different cover crops in spring maize(zea mays L.) monocultures proposed in the North China Plain. A pot experiment was conducted to evaluate the effects of different winter cover crops on subsequent maize yield, soil fertility, and environmental risks of nitrogen(N) loss, and a questionnaire survey was conducted to examine factors influencing farmers' willingness to adopt cover crops in the North China Plain. Based on the same fertilization regime during the maize growing period, four winter cover crop treatments were set up, including bare fallow, hairy vetch(Vicia villosa Roth.), February orchid(Orychophragmus violaceus), and winter oilseed rape(Brassica campestris L.). The results indicated that winter cover crops significantly increased subsequent maize yield and soil organic carbon, total N, and microbial biomass carbon and N compared with the bare fallow *** incorporation of cover crops led to a negligible increase in nitrous oxide(N_(2)O) emissions and had a very limited effect on ammonia(NH_(3)) *** incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing *** N losses via N_(2)O and NH_(3) emissions and N leaching accounted for 71%–84% of the N surplus. However, yield increase and environmental benefits were not the main positive factors for farmers to accept cover crops. Financial incentive was rated by 83.9% of farmers as an “extremely important” factor, followed by other costs, when considering winter cover cropping. These results indicate that the environmental benefits depend on the type of cover crop. Maintaining high levels of soil fertility and maize yield, providing sufficient subsidies, and encouraging large-area cultivation of cover crops

关键词： cover crop N leaching NH_(3)emission N_(2)O emission spring maize willingness to accept

The impact of depositional environment and tectonic evolution on coalbed methane occurrence in West Henan, China

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International journal of Mining Science and Technology 2019年第2期29卷 297-305页

作者： zhaodan Cao Baiquan Lin Ting liu China University of Mining and Technology Department of Energy and Mineral Engineering The Pennsylvania State University University Park

A deeper understanding of the mechanisms by which geological factors(depositional environment and tectonic evolution) control the occurrence of coalbed methane(CBM) is important for the utilization of CBM resources via surface-drilled wells and the elimination of coal-methane outbursts, the latter of which is a key issue for coal mine safety. Based on drill core data, high-pressure isothermal adsorption experiments, scanning electron microscopy experiments, mercury intrusion porosimetry, and X-ray diffraction experiments, the impact of the depositional environment and tectonic evolution on CBM occurrence of the II-1 coal seam of the Shanxi Formation in West Henan was analyzed. Results showed that the depositional environment led to the epigenetic erosion of tidal flat coal-accumulating structures by shallow-delta distributary channel strata. This resulted in the replacement of the original mudstonesandy mudstone coal seam immediate roof with fine-to-medium grained sandstones, reducing methane storage capacity. Epigenetic erosion by the depositional environment also increased coal body ash content(from 6.9% to 21.4%) and mineral content, filling the cleat system and reducing porosity, reducing methane storage capacity. The maximum methane adsorption capacity of the coal body reduced from35.7 cm3/g to 30.30 cm3/g, and Langmuir pressure decreased from 1.39 MPa to 0.909 MPa. Hence, the methane adsorption capacity of the coal body decreased while its capacity for methane desorption increased. Owing to the tectonic evolution of West Henan, tectonically deformed coal is common; as it evolves from primary cataclastic coal to granulitic coal, the angle of the diffraction peak increases, d002 decreases, and La, Lc, and Nc increase; these traits are generally consistent with dynamic *** is accompanied by increases in the total pore volume and specific surface area of the coal body, further increasing the capacity for methane storage. Increases in micropore volume

关键词： Coalbed methane Depositional environment Tectonic evolution Epigenetic erosion Tectonically-deformed coal